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Sample records for radiation standards complex

  1. US Army primary radiation standards complex

    SciTech Connect

    Rogers, S.C.

    1993-12-31

    This paper describes the U.S. Army Primary Radiation Standards Complex (PRSC) to be constructed at Redstone Arsenal, Alabama. The missions of the organizations to be located in the PRSC are described. The health physics review of the facility design is discussed. The radiation sources to be available in the PRSC and the resulting measurement capabilities of the Army Primary Standards Laboratory Nucleonics section are specified. Influence of the National Voluntary Laboratory Accrediation Program (NVLAP) accreditation criteria on facility design and source selection is illustrated.

  2. ISO radiation sterilization standards

    NASA Astrophysics Data System (ADS)

    Lambert, Byron J.; Hansen, Joyce M.

    1998-06-01

    This presentation provides an overview of the current status of the ISO radiation sterilization standards. The ISO standards are voluntary standards which detail both the validation and routine control of the sterilization process. ISO 11137 was approved in 1994 and published in 1995. When reviewing the standard you will note that less than 20% of the standard is devoted to requirements and the remainder is guidance on how to comply with the requirements. Future standards developments in radiation sterilization are being focused on providing additional guidance. The guidance that is currently provided in informative annexes of ISO 11137 includes: device/packaging materials, dose setting methods, and dosimeters and dose measurement, currently, there are four Technical Reports being developed to provide additional guidance: 1. AAMI Draft TIR, "Radiation Sterilization Material Qualification" 2. ISO TR 13409-1996, "Sterilization of health care products — Radiation sterilization — Substantiation of 25 kGy as a sterilization dose for small or infrequent production batches" 3. ISO Draft TR, "Sterilization of health care products — Radiation sterilization Selection of a sterilization dose for a single production batch" li]4. ISO Draft TR, "Sterilization of health care products — Radiation sterilization-Product Families, Plans for Sampling and Frequency of Dose Audits."

  3. Radiation protection standards in space.

    PubMed

    Sinclair, W K

    1986-01-01

    Radiation protection standards for the individual exposed to ionizing radiation in his/her daily work have evolved over more than 50 years since the first recommendations on limits by the NCRP and the ICRP. Initial standards were based on the absence of observable harm, notably skin erythema, but have since been modified as other concerns, such as leukemia and genetic effects, became more important. More recently, the general carcinogenic effect of radiation has become the principal concern at low doses. Genetic effects are also of concern in the younger individual. Modern radiation protection practices take both of these risks into account. Quantification of these risks improves as new information emerges. The study of the Japanese survivors of the atomic bombs continues to yield new information and the recent revisions in the dosimetry are about to be completed. The special circumstances of space travel suggest approaches to limits not unlike those for radiation workers on the ground. One approach is to derive a career limit based on the risks of accident faced by many nonradiation workers in a lifetime. The career limit can be apportioned according to the type of mission. The NCRP is considering this and other approaches to the specification of radiation standards in space. PMID:11537242

  4. Radiation protection standards in space

    NASA Astrophysics Data System (ADS)

    Sinclair, Warren K.

    Radiation protection standards for the individual exposed to ionizing radiation in his/her daily work have evolved over more than 50 years since the first recommendations on limits by the NCRP and the ICRP. Initial standards were based on the absence of observable harm, notably skin erythema, but have since been modified as other concerns, such as leukemia and genetic effects, became more important. More recently, the general carcinogenic effect of radiation has become the principal concern at low doses. Genetic effects are also of concern in the younger individual. Modern radiation protection practices take both of these risks into account. Quantification of these risks improves as new information emerges. The study of the Japanese survivors of the atomic bombs continues to yield new information and the recent revisions in the dosimetry are about to be completed. The special circumstances of space travel suggest approaches to limits not unlike those for radiation workers on the ground. One approach is to derive a career limit based on the risks of accident faced by many nonradiation workers in a lifetime. The career limit can be apportioned according to the type of mission. The NCRP is considering this and other approaches to the specification of radiation standards in space.

  5. Provisional standards of radiation safety during flights

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Radiation effects during space flights are discussed in the context of the sources and dangers of such radiation and the radiobiological prerequisites for establishing safe levels of radiation dosage. Standard safe levels of radiation during space flight are established.

  6. Cancer complexity and radiation protection.

    PubMed

    Mossman, Kenneth L

    2014-07-01

    Management of radiological risks typically encountered in environmental and occupational settings is challenging because of uncertainties in the magnitude of the risks and the benefits of risk reduction. In practice, radiation dose instead of risk is measured. However, the relationship between dose and risk is not straightforward because cancer (the major health effect of concern at low doses) is a disease of complexity. Risks at small doses (defined as less than 100 mSv) can never be known exactly because of the inherent uncertainties in cancer as a complex disease. Tumors are complex because of the nonlinear interactions that occur among tumor cells and between the tumor and its local tissue environment. This commentary reviews evidence for cancer complexity and what complexity means for radiation protection. A complexity view of cancer does not mean we must abandon our current system of protection. What it does mean is that complexity requires new ways of thinking about control of cancer-the ideas that cancers can occur without cause, cancers behave unpredictably, and calculated cancer risks following small doses of radiation are highly uncertain. PMID:24849905

  7. New Standards for Ultraviolet Radiation

    NASA Technical Reports Server (NTRS)

    Sliney, D. H.

    1971-01-01

    Guidelines covering safe levels for exposure to ultraviolet radiation in an occupational environment are reported. The guidelines clarify the spectral radiant exposure doses and relative spectral effectiveness of ultraviolet radiation required to elicit adverse biologic effects.

  8. Environmental radiation standards. [Outline of slide presentation

    SciTech Connect

    Kocher, D.C.

    1987-01-01

    This document contains an outline of an oral presentation on environmental radiation standards presented to the American Nuclear Societies' Topical Conference on Population Exposure from the Nuclear Fuel Cycle. The paper contains several definitions, a summary of current radiation exposure limits; and numerous proposed changes to current standards. 7 figs. (TEM)

  9. Radiation standards and public perceptions of risk

    SciTech Connect

    Peterson, H.T. Jr.

    1989-01-01

    The relation between radiation standards and a perceived safe level of radiation exposure indicates that regulators must carefully describe the underlying basis for existing and new radiation standards so that public perception will not be inadvertently influenced due to changes in standard-setting philosophy. Regulators also need to qualify estimates of risks from low-level ionizing radiation (doses <5 rem/yr) to indicate that the estimated effects are potential effects only and that there is no evidence such effects actually have been observed at these doses and dose rates. However, proponents of the application of ionizing radiation and nuclear energy must also recognize that there is no concrete evidence that such effects do not occur at these doses and that, given this uncertainty as to whether the effects occur at all, it is prudent for public health protection purposes to assume that such effects could occur.

  10. Viewpoint on proposed radiation-protection standards

    SciTech Connect

    Auxier, J.A.

    1982-01-01

    The proposed revision of 10CFR20 is discussed from a personal perspective. A brief historical review of the development of radiation standards is presented, and arguments against the proposed de minimis level elaborated upon. (ACR)

  11. A standard for ultraviolet radiation.

    NASA Technical Reports Server (NTRS)

    Fisher, G. B.; Spicer, W. E.; Mckernan, P. C.; Pereskok, V. F.; Wanner, S. J.

    1973-01-01

    Photoemission diode standards for accurately measuring monochromatic ultraviolet light intensity (3000 A-1100 A) are described that are also blind to visible light. The standard uses an opaque photocathode of Cs2Te and is unique because of its combination of thinness (19 mm), high sensitivity, time stability, and uniformity of response. Design criteria, construction methods, and difficulties overcome in obtaining a stable, uniform, high yield photocathode responses are discussed. Cs2Te is discussed in terms of a model for high yield photoemitters.

  12. Standardizing Naming Conventions in Radiation Oncology

    SciTech Connect

    Santanam, Lakshmi; Hurkmans, Coen; Mutic, Sasa; Vliet-Vroegindeweij, Corine van; Brame, Scott; Straube, William; Galvin, James; Tripuraneni, Prabhakar; Michalski, Jeff; Bosch, Walter

    2012-07-15

    Purpose: The aim of this study was to report on the development of a standardized target and organ-at-risk naming convention for use in radiation therapy and to present the nomenclature for structure naming for interinstitutional data sharing, clinical trial repositories, integrated multi-institutional collaborative databases, and quality control centers. This taxonomy should also enable improved plan benchmarking between clinical institutions and vendors and facilitation of automated treatment plan quality control. Materials and Methods: The Advanced Technology Consortium, Washington University in St. Louis, Radiation Therapy Oncology Group, Dutch Radiation Oncology Society, and the Clinical Trials RT QA Harmonization Group collaborated in creating this new naming convention. The International Commission on Radiation Units and Measurements guidelines have been used to create standardized nomenclature for target volumes (clinical target volume, internal target volume, planning target volume, etc.), organs at risk, and planning organ-at-risk volumes in radiation therapy. The nomenclature also includes rules for specifying laterality and margins for various structures. The naming rules distinguish tumor and nodal planning target volumes, with correspondence to their respective tumor/nodal clinical target volumes. It also provides rules for basic structure naming, as well as an option for more detailed names. Names of nonstandard structures used mainly for plan optimization or evaluation (rings, islands of dose avoidance, islands where additional dose is needed [dose painting]) are identified separately. Results: In addition to its use in 16 ongoing Radiation Therapy Oncology Group advanced technology clinical trial protocols and several new European Organization for Research and Treatment of Cancer protocols, a pilot version of this naming convention has been evaluated using patient data sets with varying treatment sites. All structures in these data sets were

  13. Heat standards calibration in the DOE complex

    SciTech Connect

    Carillo, L.A.; Rudy, C.R.; Long, S.M.; McDaniel, J.; Rodenburg, W.W.

    1997-11-01

    As part of the Department of Energy (DOE) Non-nuclear Reconfiguration Program, the Office of Safeguards and Security Calorimetry Development Program has transferred from EG and G Mound Applied Technologies to the Los Alamos National Laboratory. An important function of this program is the calibration and certification of {sup 238}Pu heat standards, which are used to assure accountability of plutonium and tritium throughout the complex. To facilitate relatively uninterrupted calibration service, two calorimeters have been installed in the Los Alamos Plutonium Facility (TA-55). These calorimeters are capable of highly accurate measurements of heat standards with power ranging from 0.01 to 20 W. In addition, two new EG and G Mound Applied Technologies calibration calorimeters with a robot handling system have been installed in the Nuclear Safeguards Laboratories at Los Alamos National Laboratory. These calorimeters are located in a specially constructed laboratory that is controlled for temperature and humidity to achieve low uncertainty in the measurements. Because transportation of aging heat standards between sites within the DOE complex has become increasingly difficult, the authors are looking into several approaches to this problem. Repackaging of all heat standards to comply with Department of Transportation and American Nuclear Standards Institute requirements is a long-term goal.

  14. 41 CFR 50-204.36 - Radiation standards for mining.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... Department of Labor, Radiation Safety and Health Standards (41 CFR 50-204.36). You should preserve this... mining. 50-204.36 Section 50-204.36 Public Contracts and Property Management Other Provisions Relating to... CONTRACTS Radiation Standards § 50-204.36 Radiation standards for mining. (a) For the purpose of...

  15. 41 CFR 50-204.36 - Radiation standards for mining.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... Department of Labor, Radiation Safety and Health Standards (41 CFR 50-204.36). You should preserve this... mining. 50-204.36 Section 50-204.36 Public Contracts and Property Management Other Provisions Relating to... CONTRACTS Radiation Standards § 50-204.36 Radiation standards for mining. (a) For the purpose of...

  16. 41 CFR 50-204.36 - Radiation standards for mining.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... Department of Labor, Radiation Safety and Health Standards (41 CFR 50-204.36). You should preserve this... mining. 50-204.36 Section 50-204.36 Public Contracts and Property Management Other Provisions Relating to... CONTRACTS Radiation Standards § 50-204.36 Radiation standards for mining. (a) For the purpose of...

  17. 41 CFR 50-204.36 - Radiation standards for mining.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... Department of Labor, Radiation Safety and Health Standards (41 CFR 50-204.36). You should preserve this... mining. 50-204.36 Section 50-204.36 Public Contracts and Property Management Other Provisions Relating to... CONTRACTS Radiation Standards § 50-204.36 Radiation standards for mining. (a) For the purpose of...

  18. 41 CFR 50-204.36 - Radiation standards for mining.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... Department of Labor, Radiation Safety and Health Standards (41 CFR 50-204.36). You should preserve this... mining. 50-204.36 Section 50-204.36 Public Contracts and Property Management Other Provisions Relating to... CONTRACTS Radiation Standards § 50-204.36 Radiation standards for mining. (a) For the purpose of...

  19. New standards for ionizing radiation measurements

    SciTech Connect

    Lamperti, P.J.; Johnson, C.M.

    1995-12-31

    The Ionizing Radiation Division has developed new national standards for mammographic X rays and for brachytherapy sources, such as iodine-125. The Attix chamber, a variable volume free-air ionization chamber, has been established as the primary national standard for mammographic X rays. The Attix chamber resides in the newly developed NIST Mammography Calibration Range and will be used to perform routine calibrations. The wide-angle free-air ionization chamber utilizes a large volume and a novel electric field configuration in order to circumvent the limitations of conventional free-air chambers. Seventeen beam qualities for X rays from molybdenum (Mo) and rhodium (Rh) anodes have been parameterized for the calibration of mammographic ionization chambers. The beam qualities available include anode/filter combinations of Mo/Mo, Mo/Rh and Rh/Rh. The mammography range was developed in collaborations with the U.S. Food and Drug Administration`s (FDA) Center for Devices and Radiological Health, the implementors of the Mammography Quality Standards Act (MQSA) of 1992. The wide-angle free-air ionization chamber has been used to measure the output of two types of iodine-125 seeds, those with resin balls and those with silver wire. Both free-air chambers have been intercompared with the Ritz parallel-plate free-air ionization chamber.

  20. Review of standards for limitation of radiation dose to radiation workers and members of the public

    SciTech Connect

    Kocher, D.C.

    1992-01-01

    Topics covered in the review include: current radiation protection standards for workers; current radiation protection standards for the routine exposures of the public; environmental radiation standards for specific practices or sources; protective action guides for accidental releases of radioactivity to the environment; de minimis dose, exempt levels of radioactivity, and below regulatory concern.

  1. Review of standards for limitation of radiation dose to radiation workers and members of the public

    SciTech Connect

    Kocher, D.C.

    1992-07-01

    Topics covered in the review include: current radiation protection standards for workers; current radiation protection standards for the routine exposures of the public; environmental radiation standards for specific practices or sources; protective action guides for accidental releases of radioactivity to the environment; de minimis dose, exempt levels of radioactivity, and below regulatory concern.

  2. IEC STANDARDS FOR INDIVIDUAL MONITORING OF IONISING RADIATION

    SciTech Connect

    Voytchev, Miroslav; Ambrosi, P.; Behrens, R.; Chiaro Jr, Peter John

    2011-01-01

    This paper presents IEC/SC 45B Radiation protection instrumentation and its standards for individual monitoring of ionising radiation: IEC 61526 Ed. 3 for active personal dosemeters and IEC 62387-1 for passive integrating dosimetry systems. The transposition of these standards as CENELEC (European) standards is also discussed together with the collaboration between IEC/SC 45B and ISO/TC 85/SC 2.

  3. A new standard for core training in radiation safety

    SciTech Connect

    Trinoskey, P.A.

    1997-02-01

    A new American National Standard for radiation worker training was recently developed. The standard emphasizes performance-based training and establishing a training program rather than simply prescribing objectives. The standard also addresses basic criteria, including instructor qualifications. The standard is based on input from a wide array of regulatory agencies, universities, national laboratories, and nuclear power entities. This paper presents an overview of the new standard and the philosophy behind it. The target audience includes radiation workers, management and supervisory personnel, contractors, students, emergency personnel, and visitors.

  4. IEC International Standards Under Development For Radiation-Generating Devices

    SciTech Connect

    Voytchev, M; Radev, R; Chiaro, P; Thomson, I; Dray, C; Li, J

    2007-12-06

    The International Electrotechnical Commission (IEC) is the leading and oldest global organization with over 100 years history of developing and publishing international standards for all electrical, electronic and related technologies, including radiation detection instrumentation. Subcommittee 45B 'Radiation Protection Instrumentation' of the IEC has recently started the development of two standards on radiation-generating devices. IEC 62463 'Radiation protection instrumentation--X-ray Systems for the Screening of Persons for Security and the Carrying of Illicit Items' is applicable to X-ray systems designed for screening people to detect if they are carrying objects such as weapons, explosives, chemical and biological agents and other concealed items that could be used for criminal purposes, e.g. terrorist use, drug smuggling, etc. IEC 62523 'Radiation protection instrumentation--Cargo/Vehicle radiographic inspection systems' applies to cargo/vehicle imaging inspection systems using accelerator produced X-ray or gamma radiation to obtain images of the screened objects (e.g. cargo containers, transport and passenger vehicles and railroad cars). The objective of both standards is to specify standard requirements and general characteristics and test procedures, as well as, radiation, electrical, environmental, mechanical, and safety requirements and to provide examples of acceptable methods to test these requirements. In particular the standards address the design requirements as they relate to the radiation protection of the people being screened, people who are in the vicinity of the equipment and the operators. The standard IEC 62463 does not deal with the performance requirements for the quality of the object detection. Compliance with the standards requirements will provide the manufacturers with internationally acceptable specifications and the device users with assurance of the rigorous quality and accuracy of the measurements in relation to the radiological

  5. Twenty new ISO standards on dosimetry for radiation processing

    NASA Astrophysics Data System (ADS)

    Farrar, H., IV

    2000-03-01

    Twenty standards on essentially all aspects of dosimetry for radiation processing were published as new ISO standards in December 1998. The standards are based on 20 standard practices and guides developed over the past 14 years by Subcommittee E10.01 of the American Society for Testing and Materials (ASTM). The transformation to ISO standards using the 'fast track' process under ISO Technical Committee 85 (ISO/TC85) commenced in 1995 and resulted in some overlap of technical information between three of the new standards and the existing ISO Standard 11137 Sterilization of health care products — Requirements for validation and routine control — Radiation sterilization. Although the technical information in these four standards was consistent, compromise wording in the scopes of the three new ISO standards to establish precedence for use were adopted. Two of the new ISO standards are specifically for food irradiation applications, but the majority apply to all forms of gamma, X-ray, and electron beam radiation processing, including dosimetry for sterilization of health care products and the radiation processing of fruit, vegetables, meats, spices, processed foods, plastics, inks, medical wastes, and paper. Most of the standards provide exact procedures for using individual dosimetry systems or for characterizing various types of irradiation facilities, but one covers the selection and calibration of dosimetry systems, and another covers the treatment of uncertainties using the new ISO Type A and Type B evaluations. Unfortunately, nine of the 20 standards just adopted by the ISO are not the most recent versions of these standards and are therefore already out of date. To help solve this problem, efforts are being made to develop procedures to coordinate the ASTM and ISO development and revision processes for these and future ASTM-originating dosimetry standards. In the meantime, an additional four dosimetry standards have recently been published by the ASTM but

  6. Ultraviolet Radiation Dose National Standard of México

    NASA Astrophysics Data System (ADS)

    Cardoso, R.; Rosas, E.

    2006-09-01

    We present the Ultraviolet (UV) Radiation Dose National Standard for México. The establishment of this measurement reference at Centro Nacional de Metrología (CENAM) eliminates the need of contacting foreign suppliers in the search for traceability towards the SI units when calibrating instruments at 365 nm. Further more, the UV Radiation Dose National Standard constitutes a highly accurate and reliable source for the UV radiation dose measurements performed in medical and cosmetic treatments as in the the food and pharmaceutics disinfection processes, among other.

  7. Radar cross sections of standard and complex shape targets

    NASA Technical Reports Server (NTRS)

    Sohel, M. S.

    1974-01-01

    The theoretical, analytical, and experimental results are described for radar cross sections (RCS) of different-shaped targets. Various techniques for predicting RCS are given, and RCS of finite standard targets are presented. Techniques used to predict the RCS of complex targets are made, and the RCS complex shapes are provided.

  8. Transport and radiation in complex LTE mixtures

    NASA Astrophysics Data System (ADS)

    Janssen, Jesper; Peerenboom, Kim; Suijker, Jos; Gnybida, Mykhailo; van Dijk, Jan

    2014-10-01

    Complex LTE mixtures are for example encountered in re-entry, welding, spraying and lighting. These mixtures typically contain a rich chemistry in combination with large temperature gradients. LTE conditions are also interesting because they can aid in the validation of NLTE algorithms. An example is the calculation of transport properties. In this work a mercury free high intensity discharge lamp is considered. The investigation focusses on using salts like InI or SnI as a buffer species. By using these species a dominant background gas like mercury is no longer present. As a consequence the diffusion algorithms based on Fick's law are no longer applicable and the Stefan-Maxwell equations must be solved. This system of equations is modified with conservation rules to set a coldspot pressure for saturated species and enforce the mass dosage for unsaturated species. The radiative energy transport is taken into account by raytracing. Quantum mechanical simulations have been used to calculate the potential curves and the transition dipole moments for indium with iodine and tin with iodine. The results of these calculations have been used to predict the quasistatic broadening by iodine. The work was supported by the project SCHELP from the Belgium IWT (Project Number 110003) and the CATRENE SEEL Project (CA502).

  9. The Common Core State Standards' Quantitative Text Complexity Trajectory: Figuring out How Much Complexity Is Enough

    ERIC Educational Resources Information Center

    Williamson, Gary L.; Fitzgerald, Jill; Stenner, A. Jackson

    2013-01-01

    The Common Core State Standards (CCSS) set a controversial aspirational, quantitative trajectory for text complexity exposure for readers throughout the grades, aiming for all high school graduates to be able to independently read complex college and workplace texts. However, the trajectory standard is presented without reference to how the…

  10. Radiation hardness of Efratom M-100 rubidium frequency standard

    NASA Technical Reports Server (NTRS)

    English, T. C.; Vorwerk, H.; Rudie, N. J.

    1983-01-01

    The effects of nuclear radiation on rubidium gas cell frequency standards and components are presented, including the results of recent tests where a continuously operating rubidium frequency standard (Effratom, Model M-100) was subjected to simultaneous neutron/gamma radiation. At the highest neutron fluence 7.5 10 to the 12th power n/sq cm and total dose 11 krad(Si) tested, the unit operated satisfactorily; the total frequency change over the 2 1/2 hour test period due to all causes, including repeated retraction from and insertion into the reactor, was less than 1 x 10 to the -10th power. The effects of combined neutron/gamma radiation on rubidium frequency standard physics package components were also studied, and the results are presented.

  11. Setting standards for radiation protection: A time for change

    SciTech Connect

    Patterson, H.W.; Hickman, D.P.

    1996-01-01

    In 1950, the International Commission on Radiation Protection (ICRP) recommended that ``certain radiation effects are irreversible and cumulative.`` Furthermore, the ICRP ``strongly recommended that every effort be made to reduce exposures to all types of ionizing radiations to the lowest possible level.`` Then in 1954, the ICRP published its assumption that human response to ionizing radiation was linear with dose, together with the recommendation that exposures be kept as low as practicable. These concepts are still the foundation of radiation protection policy today, even though, as Evans has stated, ``The linear non-threshold (LNT) model was adopted specifically on a basis of mathematical simplicity, not from radio-biological data.... Groups responsible for setting standards for radiation protection should be abreast of new developments and new data as they are published; however, this does not seem to be the case. For example, there have been many reports in scientific, peer-reviewed, and other publications during the last three decades that have shown the LNT model and the policy of As Low As Reasonably Achievable (ALARA) to be invalid. However, none of these reports has been refuted or even discussed by standard-setting groups. We believe this mandates a change in the standard-setting process.

  12. 1500 Gate standard cell compatible radiation hard gate array

    SciTech Connect

    Mills, B.D.; Shafer, B.D.; Melancon, E.P.

    1984-11-01

    The G1500 gate array combines Sandia Labs' 4/3..mu.. CMOS silicon gate radiation hard process with a novel gate isolated standard cell compatible design for quick turnaround time, low cost, and radiation hardness. This device is hard to 5 x 10/sup 5/ rads, utilizes a configuration that provides high packing density, and is supported on both the Daisy and Mentor workstations. This paper describes Sandia Labs' radiation hard 4/3..mu.. process, the G1500's unique design, and the complete design capabilities offered by the workstations.

  13. International cooperative effort to establish dosimetry standardization for radiation processing

    SciTech Connect

    Farrar, H. IV

    1989-01-01

    Radiation processing is a rapidly developing technology with numerous applications in food treatment, sterilization, and polymer modification. The effectiveness of the process depends, however, on the proper application of dose and its measurement. These aspects are being considered by a wide group of experts from around the world who have joined together to write a comprehensive set of standards for dosimetry for radiation processing. Originally formed in 1984 to develop standards for food processing dosimetry, the group has now expanded into a full subcommittee of the American Society for Testing and Materials (ASTM), with 97 members from 19 countries. The scope of the standards now includes dosimetry for all forms of radiation processing. The group has now completed and published four standards, and is working on an additional seven. Three are specifically for food applications and the others are for all radiation applications, including food processing. Together, this set of standards will specify acceptable guidelines and methods for accomplishing the required irradiation treatment, and will be available for adoption by national regulatory agencies in their procedures and protocols. 1 tab.

  14. Radiative breaking of conformal symmetry in the Standard Model

    NASA Astrophysics Data System (ADS)

    Arbuzov, A. B.; Nazmitdinov, R. G.; Pavlov, A. E.; Pervushin, V. N.; Zakharov, A. F.

    2016-02-01

    Radiative mechanism of conformal symmetry breaking in a comformal-invariant version of the Standard Model is considered. The Coleman-Weinberg mechanism of dimensional transmutation in this system gives rise to finite vacuum expectation values and, consequently, masses of scalar and spinor fields. A natural bootstrap between the energy scales of the top quark and Higgs boson is suggested.

  15. A review of the history of U.S. radiation protection regulations, recommendations, and standards.

    PubMed

    Jones, Cynthia Gillian

    2005-02-01

    Shortly after the discovery of x rays by Wilhelm Konrad Roentgen in 1895, and the isolation of the element radium by Pierre and Marie Curie three years later, the fascination with and potential for an array of uses of ionizing radiation in medicine, science, and technology was born. As with any new technology, there was a need to balance both the beneficial and potential detrimental effects of uses of these new technologies for the advancement of humankind. In the early days, radiation hazards were not well understood. Over the decades increasing concerns in the scientific community and lay population demanded that standardized guidance and recommendations be developed for the use of ionizing radiation. Today, U.S. radiation protection standards and recommendations to protect the occupational worker, members of the general public, and the environment are numerous and complex. This review summarizes the history of the development and application of radiation protection standards and regulations to assure the safe use of radiation and radioactive materials. The evolution and roles of international and national scientific recommending and regulatory organizations that shape U.S. radiation protection policy are described and discussed. PMID:15650586

  16. A review of the history of U.S. radiation protection regulations, recommendations, and standards.

    PubMed

    Jones, Cynthia G

    2005-06-01

    Shortly after the discovery of x rays by Wilhelm Konrad Roentgen in 1895, and the isolation of the element radium by Pierre and Marie Curie three years later, the fascination with and potential for an array of uses of ionizing radiation in medicine, science, and technology was born. As with any new technology, there was a need to balance both the beneficial and potential detrimental effects of uses of these new technologies for the advancement of humankind. In the early days, radiation hazards were not well understood. Over the decades increasing concerns in the scientific community and lay population demanded that standardized guidance and recommendations be developed for the use of ionizing radiation. Today, U.S. radiation protection standards and recommendations to protect the occupational worker, members of the general public, and the environment are numerous and complex. This review summarizes the history of the development and application of radiation protection standards and regulations to assure the safe use of radiation and radioactive materials. The evolution and roles of international and national scientific recommending and regulatory organizations that shape U.S. radiation protection policy are described and discussed. PMID:15891462

  17. Further progress in the characterisation of complex radiation fields.

    PubMed

    Spurny, Frantisek; Silari, Marco

    2008-01-01

    One of the topics which forms part of CONRAD project addresses the problems related to the dosimetry of complex-mixed radiation fields at workplaces. This topic was included in work package (WP) 6. WP 6 was established to co-ordinate research activities in two areas:the development of new techniques and the improvement of current techniques for characterisation of complex workplace fields (including high-energy fields and pulsed fields): measurement and calculation of particle energy and direction distributions (Subgroup A); and model improvements for dose assessment of solar particle events (Subgroup B). In both cases in order to aid the research, WP 6 increases the efficiency of resource utilisation, and facilitates the technology transfer to practical application and for the development of standards. This contribution presents a general overview of activities of SG A; specific results related to the benchmark experiment at GSI Darmstadt are presented separately, and will be published in other way. As far as the results acquired in the frame of the SG B activities, these are presented in the meeting held as part of EURADOS AM 2008. PMID:18718960

  18. Radiation safety of crew and passengers of air transportation in civil aviation. Provisional standards

    SciTech Connect

    Aksenov, A.F.; Burnazyan, A.I.

    1985-03-01

    The purpose and application of the provisional standards for radiation safety of crew and passengers in civil aviation are given. The radiation effect of cosmic radiation in flight on civil aviation air transport is described. Standard levels of radiation and conditions of radiation safety are discussed.

  19. Radiation safety of crew and passengers of air transportation in civil aviation. Provisional standards

    NASA Technical Reports Server (NTRS)

    Aksenov, A. F.; Burnazyan, A. I.

    1985-01-01

    The purpose and application of the provisional standards for radiation safety of crew and passengers in civil aviation are given. The radiation effect of cosmic radiation in flight on civil aviation air transport is described. Standard levels of radiation and conditions of radiation safety are discussed.

  20. Monochromator-Based Absolute Calibration of a Standard Radiation Thermometer

    NASA Astrophysics Data System (ADS)

    Mantilla, J. M.; Hernanz, M. L.; Campos, J.; Martín, M. J.; Pons, A.; del Campo, D.

    2014-04-01

    Centro Español de Metrología (CEM) is disseminating the International Temperature Scale (ITS-90), at high temperatures, by using the fixed points of Ag and Cu and a standard radiation thermometer. However, the future mise-en-pratique for the definition of the kelvin ( MeP-K) will include the dissemination of the kelvin by primary methods and by indirect approximations capable of exceptionally low uncertainties or increased reliability. Primary radiometry is, at present, able to achieve uncertainties competitive with the ITS-90 above the silver point with one of the possible techniques the calibration for radiance responsivity of an imaging radiometer (radiance method). In order to carry out this calibration, IO-CSIC (Spanish Designated Institute for luminous intensity and luminous flux) has collaborated with CEM, allowing traceability to its cryogenic radiometer. A monochromator integrating sphere-based spectral comparator facility has been used to calibrate one of the CEM standard radiation thermometers. The absolute calibrated standard radiation thermometer has been used to determine the temperatures of the fixed points of Cu, Co-C, Pt-C, and Re-C. The results obtained are 1357.80 K, 1597.10 K, 2011.66 K, and 2747.64 K, respectively, with uncertainties ranging from 0.4 K to 1.1 K.

  1. Environmental Radiation Protection Standards for Yucca Mountain, Nevada

    SciTech Connect

    Clark, R. L.

    2002-02-27

    The Environmental Protection Agency (EPA) has issued radiation protection standards for the potential spent nuclear fuel and high-level radioactive waste disposal system in Yucca Mountain, Nevada. These standards are found in Part 197 of Title 40 of the Code of Federal Regulations (40 CFR Part 197). The Energy Policy Act of 1992 directed, and gave the authority to, EPA to take this action based upon input from the National Academy of Sciences (NAS). The final standards were published in the Federal Register (66 FR 32073) on 13 June 2001. The 40 CFR Part 197 standards have four major parts: (1) individual-protection during storage activities; (2) individual-protection following closure of the repository; (3) human-intrusion; and (4) ground-water protection. The storage standard is 150 microsieverts (Sv) annual committed effective dose equivalent (CEDE) to any member of the general public. The disposal standards are: (1) 150 Sv annual CEDE for the reasonably maximally exposed individual (RMEI) for 10,000 years after disposal; (2) 150 Sv received by the RMEI within 10,000 years after disposal as a result of human intrusion; and (3) the levels of radionuclides in the ground water cannot exceed 40 Sv from beta and gamma emitters, 5 picocuries per liter (pCi/L) of radium-226 and -228, and 15 pCi/L of gross alpha activity. There are also requirements related to the post-10,000-year period, the basis of compliance judgments, and performance assessments. The Agency has published its responses to the comments received, its technical background document, and its economic impact analysis. In addition to printed form, the documents are available on the World Wide Web at http://www.epa.gov/radiation/yucca/index.html.

  2. Absorbed dose to water: Standards and traceability for radiation oncology

    SciTech Connect

    Almond, P.R.

    1995-12-31

    Although the need for appropriate quantities and units for ionizing radiation has existed since shortly after discovery of X-rays, the quantities and units in general use today were not completely formalized until about 15 years ago. The development of appropriate national and international standards have also been ongoing. For many years the quantity, exposure, measured in units of roentgen was the national standard and they were also the quantity and units in which radiotherapy was described. With the introduction of megavoltage X-ray and electron-beam equipment and the adoption of the quantity {open_quotes}absorbed-dose{close_quotes} measured in units of rad (or gray) different approaches to calibrating these beams were needed. This was especially the case since the national standard in terms of exposure at a maximum photon energy for {sup 60}Co gamma rays was only available. Since the late 1960s various machine calibration protocols have been published. These protocols have to accommodate changes in modality, energy, quantities and units between the national standard and the user. Because of this, a new definition of traceability is proposed to accommodate the present system. By recording all intercomparisons and parameters used, an auditable calibration chain can be maintained. Even with the introduction of calibration protocols based upon national absorbed dose standards, the proposed traceability definition will still be needed.

  3. The MCART Radiation Physics Core: The Quest for Radiation Dosimetry Standardization

    PubMed Central

    Kazi, Abdul M.; MacVittie, Thomas J.; Lasio, Giovanni; Lu, Wei; Prado, Karl L.

    2013-01-01

    Dose-related radiobiological research results can only be meaningfully compared when radiation dosimetry is standardized. To this purpose, the National Institute of Allergy and Infectious Diseases (NIAID)-sponsored Medical Countermeasures Against Radiological Threats (MCART) consortium recently created a Radiation Physics Core (RPC) as an entity to assume responsibility of standardizing radiation dosimetry practices among its member laboratories. The animal research activities in these laboratories utilize a variety of ionizing photon beams from several irradiators such as 250–320 kVp x-ray generators, 137Cs irradiators, 60Co teletherapy machines, and medical linear accelerators (LINACs). In addition to this variety of sources, these centers utilize a range of irradiation techniques and make use of different dose calculation schemes to conduct their experiments. An extremely important objective in these research activities is to obtain a Dose Response Relationship (DRR) appropriate to their respective organ-specific models of acute and delayed radiation effects. A clear and unambiguous definition of the DRR is essential for the development of medical countermeasures. It is imperative that these DRRs are transparent between centers. The MCART RPC has initiated the establishment of standard dosimetry practices among member centers and is introducing a Remote Dosimetry Monitoring Service (RDMS) to ascertain ongoing quality assurance. In this paper we will describe the initial activities of the MCART RPC toward implementing these standardization goals. It is appropriate to report a summary of initial activities with the intent of reporting the full implementation at a later date. PMID:24276553

  4. 76 FR 70130 - Notice of Public Meeting of the Interagency Steering Committee on Radiation Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-10

    ... AGENCY Notice of Public Meeting of the Interagency Steering Committee on Radiation Standards AGENCY... (EPA) will host a meeting of the Interagency Steering Committee on Radiation Standards (ISCORS) on... of regulatory issues associated with radiation standards. Agencies represented as members of...

  5. 78 FR 54248 - Notice of Public Meeting of the Interagency Steering Committee on Radiation Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-03

    ... AGENCY Notice of Public Meeting of the Interagency Steering Committee on Radiation Standards AGENCY... Agency (EPA) will host a meeting of the Interagency Steering Committee on Radiation Standards (ISCORS) on... of regulatory issues associated with radiation standards. Member agencies include: EPA; the...

  6. 75 FR 66092 - Notice of Public Meeting of the Interagency Steering Committee on Radiation Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-27

    ... AGENCY Notice of Public Meeting of the Interagency Steering Committee on Radiation Standards AGENCY... (EPA) will host a meeting of the Interagency Steering Committee on Radiation Standards (ISCORS) on... of regulatory issues associated with radiation standards. Agencies represented as members of...

  7. 21 CFR 14.120 - Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Radiation Safety Standards Committee (TEPRSSC). 14.120 Section 14.120 Food and Drugs FOOD AND DRUG... Technical Electronic Products Radiation Safety Standards Committee § 14.120 Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC). The Technical Electronic Product...

  8. 21 CFR 14.120 - Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Radiation Safety Standards Committee (TEPRSSC). 14.120 Section 14.120 Food and Drugs FOOD AND DRUG... Technical Electronic Products Radiation Safety Standards Committee § 14.120 Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC). The Technical Electronic Product...

  9. 21 CFR 14.120 - Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Radiation Safety Standards Committee (TEPRSSC). 14.120 Section 14.120 Food and Drugs FOOD AND DRUG... Technical Electronic Products Radiation Safety Standards Committee § 14.120 Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC). The Technical Electronic Product...

  10. 21 CFR 14.120 - Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Radiation Safety Standards Committee (TEPRSSC). 14.120 Section 14.120 Food and Drugs FOOD AND DRUG... Technical Electronic Products Radiation Safety Standards Committee § 14.120 Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC). The Technical Electronic Product...

  11. Robotic Delivery of Complex Radiation Volumes for Small Animal Research

    PubMed Central

    Matinfar, Mohammad; Iordachita, Iulian; Wong, John; Kazanzides, Peter

    2011-01-01

    The Small Animal Radiation Research Platform (SARRP) is a novel and complete system capable of delivering multidirectional (focal), kilo-voltage radiation fields to targets in small animals under robotic control using cone-beam CT (CBCT) image guidance. The capability of the SARRP to deliver highly focused beams to multiple animal models provides new research opportunities that more realistically bridge laboratory research and clinical translation. This paper describes the design and operation of the SARRP for precise radiation delivery. Different delivery procedures are presented which enable the system to radiate through a series of points, representative of a complex shape. A particularly interesting case is shell dose irradiation, where the goal is to deliver a high dose of radiation to the shape surface, with minimal dose to the shape interior. The ability to deliver a dose shell allows mechanistic research of how a tumor interacts with its microenvironment to sustain its growth and lead to its resistance or recurrence. PMID:21643448

  12. A novel approach to characterize information radiation in complex networks

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoyang; Wang, Ying; Zhu, Lin; Li, Chao

    2016-06-01

    The traditional research of information dissemination is mostly based on the virus spreading model that the information is being spread by probability, which does not match very well to the reality, because the information that we receive is always more or less than what was sent. In order to quantitatively describe variations in the amount of information during the spreading process, this article proposes a safety information radiation model on the basis of communication theory, combining with relevant theories of complex networks. This model comprehensively considers the various influence factors when safety information radiates in the network, and introduces some concepts from the communication theory perspective, such as the radiation gain function, receiving gain function, information retaining capacity and information second reception capacity, to describe the safety information radiation process between nodes and dynamically investigate the states of network nodes. On a micro level, this article analyzes the influence of various initial conditions and parameters on safety information radiation through the new model simulation. The simulation reveals that this novel approach can reflect the variation of safety information quantity of each node in the complex network, and the scale-free network has better "radiation explosive power", while the small-world network has better "radiation staying power". The results also show that it is efficient to improve the overall performance of network security by selecting nodes with high degrees as the information source, refining and simplifying the information, increasing the information second reception capacity and decreasing the noises. In a word, this article lays the foundation for further research on the interactions of information and energy between internal components within complex systems.

  13. Radiation damage to nucleoprotein complexes in macromolecular crystallography

    PubMed Central

    Bury, Charles; Garman, Elspeth F.; Ginn, Helen Mary; Ravelli, Raimond B. G.; Carmichael, Ian; Kneale, Geoff; McGeehan, John E.

    2015-01-01

    Significant progress has been made in macromolecular crystallography over recent years in both the understanding and mitigation of X-ray induced radiation damage when collecting diffraction data from crystalline proteins. In contrast, despite the large field that is productively engaged in the study of radiation chemistry of nucleic acids, particularly of DNA, there are currently very few X-ray crystallographic studies on radiation damage mechanisms in nucleic acids. Quantitative comparison of damage to protein and DNA crystals separately is challenging, but many of the issues are circumvented by studying pre-formed biological nucleoprotein complexes where direct comparison of each component can be made under the same controlled conditions. Here a model protein–DNA complex C.Esp1396I is employed to investigate specific damage mechanisms for protein and DNA in a biologically relevant complex over a large dose range (2.07–44.63 MGy). In order to allow a quantitative analysis of radiation damage sites from a complex series of macromolecular diffraction data, a computational method has been developed that is generally applicable to the field. Typical specific damage was observed for both the protein on particular amino acids and for the DNA on, for example, the cleavage of base-sugar N1—C and sugar-phosphate C—O bonds. Strikingly the DNA component was determined to be far more resistant to specific damage than the protein for the investigated dose range. At low doses the protein was observed to be susceptible to radiation damage while the DNA was far more resistant, damage only being observed at significantly higher doses. PMID:25723923

  14. 10 CFR 71.47 - External radiation standards for all packages.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CFR 20.1502. (c) For shipments made under the provisions of paragraph (b) of this section, the shipper... 10 Energy 2 2011-01-01 2011-01-01 false External radiation standards for all packages. 71.47... MATERIAL Package Approval Standards § 71.47 External radiation standards for all packages. (a) Except...

  15. 10 CFR 71.47 - External radiation standards for all packages.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... CFR 20.1502. (c) For shipments made under the provisions of paragraph (b) of this section, the shipper... 10 Energy 2 2010-01-01 2010-01-01 false External radiation standards for all packages. 71.47... MATERIAL Package Approval Standards § 71.47 External radiation standards for all packages. (a) Except...

  16. 10 CFR 71.47 - External radiation standards for all packages.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... CFR 20.1502. (c) For shipments made under the provisions of paragraph (b) of this section, the shipper... 10 Energy 2 2014-01-01 2014-01-01 false External radiation standards for all packages. 71.47... MATERIAL Package Approval Standards § 71.47 External radiation standards for all packages. (a) Except...

  17. 10 CFR 71.47 - External radiation standards for all packages.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... CFR 20.1502. (c) For shipments made under the provisions of paragraph (b) of this section, the shipper... 10 Energy 2 2013-01-01 2013-01-01 false External radiation standards for all packages. 71.47... MATERIAL Package Approval Standards § 71.47 External radiation standards for all packages. (a) Except...

  18. Multi-staged flap reconstruction for complex radiation thoracic ulcer

    PubMed Central

    Valença-Filipe, Rita; Horta, Ricardo; Costa, Joana; Carvalho, Jorge; Martins, Apolino; Silva, Álvaro

    2014-01-01

    INTRODUCTION Chest wall reconstruction due to previous radiation therapy can be challenging and complex, requiring a multidisciplinary approach. PRESENTATION OF CASE The authors present the case of a 84-year-old woman with a right chest wall radionecrosis ulcer, that was submitted to an ablative surgery resulting in a full-thickness defect of 224 cm2, firstly reconstructed with a pedicled omental flap. Due to partial flap necrosis, other debridements and chest wall multi-staged flap reconstruction were performed. DISCUSSION This case highlights that the reconstructive choice should be individualized and dependent on patient and local factors. The authors advise that surgical team should work closely and be well versed in chest wall reconstruction with a variety of pedicled flaps, when a complication occurs. CONCLUSION A multi-staged flap reconstruction could be a salvage procedure for the coverage of complex, great and complicated chest wall defects due to previous radiation therapy. PMID:25437678

  19. Formation of Complex Molecules via radiative association reactions

    NASA Astrophysics Data System (ADS)

    Acharyya, Kinsuk; Herbst, Eric

    2016-07-01

    The detection of increasing numbers of complex organic molecules in the various phases of star formation plays a key role since they follow the same chemical rules of carbon-based chemistry that are observed in our planet Earth. Many of these molecules are believed to be formed on the surfaces of grains, and can then be released to the gas phase when these grains are heated. This is evident when we observe a rich chemistry in hot core regions. However, recently complex organic molecules have also been observed in cold clouds. Therefore, it is necessary to re-examine various pathways for the formation of these molecules in the gas phase. In this presentation, I will discuss role of radiative association reactions in the formation of complex molecules in the gas phase and at low temperature. We will compare abundance of assorted molecules with and without new radiative association reactions and will show that the abundance of a few complex molecules such as HCOOCH3, CH3OCH3 etc. can go up due to introduction of these reactions, which can help to explain their observed abundances.

  20. Standards for Radiation Effects Testing: Ensuring Scientific Rigor in the Face of Budget Realities and Modern Device Challenges

    NASA Technical Reports Server (NTRS)

    Lauenstein, J M.

    2015-01-01

    An overview is presented of the space radiation environment and its effects on electrical, electronic, and electromechanical parts. Relevant test standards and guidelines are listed. Test standards and guidelines are necessary to ensure best practices, minimize and bound systematic and random errors, and to ensure comparable results from different testers and vendors. Test standards are by their nature static but exist in a dynamic environment of advancing technology and radiation effects research. New technologies, failure mechanisms, and advancement in our understanding of known failure mechanisms drive the revision or development of test standards. Changes to standards must be weighed against their impact on cost and existing part qualifications. There must be consensus on new best practices. The complexity of some new technologies exceeds the scope of existing test standards and may require development of a guideline specific to the technology. Examples are given to illuminate the value and limitations of key radiation test standards as well as the challenges in keeping these standards up to date.

  1. National Education Standards: The Complex Challenge for Educational Leaders.

    ERIC Educational Resources Information Center

    Faidley, Ray; Musser, Steven

    1991-01-01

    National standards for education are important elements in the excellence process, but standards imposed by a central authority simply do not work in the Information Era. It would be wise to increase teachers' decision-making role in establishing and implementing local level excellence standards and train teachers to employ the Japanese "kaizen"…

  2. Spectrum of complex DNA damages depends on the incident radiation

    NASA Astrophysics Data System (ADS)

    Hada, M.; Sutherland, B.

    Ionizing radiation induces clustered DNA damages in DNA-two or more abasic sites oxidized bases and strand breaks on opposite DNA strands within a few helical turns Clustered damages are considered to be difficult to repair and therefore potentially lethal and mutagenic damages Although induction of single strand breaks and isolated lesions has been studied extensively little is known of factors affecting induction of clusters other than double strand breaks DSB The aim of the present study was to determine whether the type of incident radiation could affect yield or spectra of specific clusters Genomic T7 DNA a simple 40 kbp linear blunt-ended molecule was irradiated in non-scavenging buffer conditions with Fe 970 MeV n Ti 980 MeV n C 293 MeV n Si 586 MeV n ions or protons 1 GeV n at the NASA Space Radiation Laboratory or with 100 kVp X-rays Irradiated DNA was treated with homogeneous Fpg or Nfo proteins or without enzyme treatment for DSB quantitation then electrophoresed in neutral agarose gels DSB Fpg-OxyPurine clusters and Nfo-Abasic clusters were quantified by number average length analysis The results show that the yields of all these complex damages depend on the incident radiation Although LETs are similar protons induced twice as many DSBs than did X-rays Further the spectrum of damage also depends on the radiation The yield damage Mbp Gy of all damages decreased with increasing linear energy transfer LET of the radiation The relative frequencies of DSBs to Abasic- and OxyBase clusters were higher

  3. Student Reading Growth Illuminates the Common Core Text-Complexity Standard: Raising Both Bars

    ERIC Educational Resources Information Center

    Williamson, Gary L.; Fitzgerald, Jill; Stenner, Jackson A.

    2014-01-01

    The Common Core State Standards (CCSS) establish a challenging text-complexity standard for all high school graduates to read at college and workplace text-complexity levels. We argue that implementation of the CCSS standard requires concurrent examination of historical student reading-growth trends. An example of a historical student average…

  4. Loss tangent and complex modulus estimated by acoustic radiation force creep and shear wave dispersion

    NASA Astrophysics Data System (ADS)

    Amador, Carolina; Urban, Matthew W.; Chen, Shigao; Greenleaf, James F.

    2012-03-01

    Elasticity imaging methods have been used to study tissue mechanical properties and have demonstrated that tissue elasticity changes with disease state. In current shear wave elasticity imaging methods typically only shear wave speed is measured and rheological models, e.g. Kelvin-Voigt, Maxwell and Standard Linear Solid, are used to solve for tissue mechanical properties such as the shear viscoelastic complex modulus. This paper presents a method to quantify viscoelastic material properties in a model-independent way by estimating the complex shear elastic modulus over a wide frequency range using time-dependent creep response induced by acoustic radiation force. This radiation force induced creep method uses a conversion formula that is the analytic solution of a constitutive equation. The proposed method in combination with shearwave dispersion ultrasound vibrometry is used to measure the complex modulus so that knowledge of the applied radiation force magnitude is not necessary. The conversion formula is shown to be sensitive to sampling frequency and the first reliable measure in time according to numerical simulations using the Kelvin-Voigt model creep strain and compliance. Representative model-free shear complex moduli from homogeneous tissue mimicking phantoms and one excised swine kidney were obtained. This work proposes a novel model-free ultrasound-based elasticity method that does not require a rheological model with associated fitting requirements.

  5. Loss tangent and complex modulus estimated by acoustic radiation force creep and shear wave dispersion.

    PubMed

    Amador, Carolina; Urban, Matthew W; Chen, Shigao; Greenleaf, James F

    2012-03-01

    Elasticity imaging methods have been used to study tissue mechanical properties and have demonstrated that tissue elasticity changes with disease state. In current shear wave elasticity imaging methods typically only shear wave speed is measured and rheological models, e.g. Kelvin-Voigt, Maxwell and Standard Linear Solid, are used to solve for tissue mechanical properties such as the shear viscoelastic complex modulus. This paper presents a method to quantify viscoelastic material properties in a model-independent way by estimating the complex shear elastic modulus over a wide frequency range using time-dependent creep response induced by acoustic radiation force. This radiation force induced creep method uses a conversion formula that is the analytic solution of a constitutive equation. The proposed method in combination with shearwave dispersion ultrasound vibrometry is used to measure the complex modulus so that knowledge of the applied radiation force magnitude is not necessary. The conversion formula is shown to be sensitive to sampling frequency and the first reliable measure in time according to numerical simulations using the Kelvin-Voigt model creep strain and compliance. Representative model-free shear complex moduli from homogeneous tissue mimicking phantoms and one excised swine kidney were obtained. This work proposes a novel model-free ultrasound-based elasticity method that does not require a rheological model with associated fitting requirements. PMID:22345425

  6. Loss tangent and complex modulus estimated by acoustic radiation force creep and shear wave dispersion

    PubMed Central

    Amador, Carolina; Urban, Matthew W; Chen, Shigao; Greenleaf, James F

    2012-01-01

    Elasticity imaging methods have been used to study tissue mechanical properties and have demonstrated that tissue elasticity changes with disease state. In current shear wave elasticity imaging methods typically only shear wave speed is measured and rheological models, e.g., Kelvin-Voigt, Maxwell and Standard Linear Solid, are used to solve for tissue mechanical properties such as the shear viscoelastic complex modulus. This paper presents a method to quantify viscoelastic material properties in a model-independent way by estimating the complex shear elastic modulus over a wide frequency range using time-dependent creep response induced by acoustic radiation force. This radiation force induced creep (RFIC) method uses a conversion formula that is the analytic solution of a constitutive equation. The proposed method in combination with Shearwave Dispersion Ultrasound Vibrometry (SDUV) is used to measure the complex modulus so that knowledge of the applied radiation force magnitude is not necessary. The conversion formula is shown to be sensitive to sampling frequency and the first reliable measure in time according to numerical simulations using the Kelvin-Voigt model creep strain and compliance. Representative model-free shear complex moduli from homogeneous tissue mimicking phantoms and one excised swine kidney were obtained. This work proposes a novel model-free ultrasound-based elasticity method that does not require a rheological model with associated fitting requirements. PMID:22345425

  7. RNA protects a nucleoprotein complex against radiation damage.

    PubMed

    Bury, Charles S; McGeehan, John E; Antson, Alfred A; Carmichael, Ian; Gerstel, Markus; Shevtsov, Mikhail B; Garman, Elspeth F

    2016-05-01

    Radiation damage during macromolecular X-ray crystallographic data collection is still the main impediment for many macromolecular structure determinations. Even when an eventual model results from the crystallographic pipeline, the manifestations of radiation-induced structural and conformation changes, the so-called specific damage, within crystalline macromolecules can lead to false interpretations of biological mechanisms. Although this has been well characterized within protein crystals, far less is known about specific damage effects within the larger class of nucleoprotein complexes. Here, a methodology has been developed whereby per-atom density changes could be quantified with increasing dose over a wide (1.3-25.0 MGy) range and at higher resolution (1.98 Å) than the previous systematic specific damage study on a protein-DNA complex. Specific damage manifestations were determined within the large trp RNA-binding attenuation protein (TRAP) bound to a single-stranded RNA that forms a belt around the protein. Over a large dose range, the RNA was found to be far less susceptible to radiation-induced chemical changes than the protein. The availability of two TRAP molecules in the asymmetric unit, of which only one contained bound RNA, allowed a controlled investigation into the exact role of RNA binding in protein specific damage susceptibility. The 11-fold symmetry within each TRAP ring permitted statistically significant analysis of the Glu and Asp damage patterns, with RNA binding unexpectedly being observed to protect these otherwise highly sensitive residues within the 11 RNA-binding pockets distributed around the outside of the protein molecule. Additionally, the method enabled a quantification of the reduction in radiation-induced Lys and Phe disordering upon RNA binding directly from the electron density. PMID:27139628

  8. RNA protects a nucleoprotein complex against radiation damage

    PubMed Central

    Bury, Charles S.; McGeehan, John E.; Antson, Alfred A.; Carmichael, Ian; Gerstel, Markus; Shevtsov, Mikhail B.; Garman, Elspeth F.

    2016-01-01

    Radiation damage during macromolecular X-ray crystallographic data collection is still the main impediment for many macromolecular structure determinations. Even when an eventual model results from the crystallographic pipeline, the manifestations of radiation-induced structural and conformation changes, the so-called specific damage, within crystalline macromolecules can lead to false interpretations of biological mechanisms. Although this has been well characterized within protein crystals, far less is known about specific damage effects within the larger class of nucleoprotein complexes. Here, a methodology has been developed whereby per-atom density changes could be quantified with increasing dose over a wide (1.3–25.0 MGy) range and at higher resolution (1.98 Å) than the previous systematic specific damage study on a protein–DNA complex. Specific damage manifestations were determined within the large trp RNA-binding attenuation protein (TRAP) bound to a single-stranded RNA that forms a belt around the protein. Over a large dose range, the RNA was found to be far less susceptible to radiation-induced chemical changes than the protein. The availability of two TRAP molecules in the asymmetric unit, of which only one contained bound RNA, allowed a controlled investigation into the exact role of RNA binding in protein specific damage susceptibility. The 11-fold symmetry within each TRAP ring permitted statistically significant analysis of the Glu and Asp damage patterns, with RNA binding unexpectedly being observed to protect these otherwise highly sensitive residues within the 11 RNA-binding pockets distributed around the outside of the protein molecule. Additionally, the method enabled a quantification of the reduction in radiation-induced Lys and Phe disordering upon RNA binding directly from the electron density. PMID:27139628

  9. 78 FR 21120 - Notice of Public Meeting of the Interagency Steering Committee on Radiation Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-09

    ...The Environmental Protection Agency (EPA) will host a meeting of the Interagency Steering Committee on Radiation Standards (ISCORS) on May 1, 2013 in Washington, DC. The purpose of ISCORS is to foster early resolution and coordination of regulatory issues associated with radiation standards. Member agencies include the EPA; Nuclear Regulatory Commission; Department of Energy; Department of......

  10. European standards for protective apparel against UV radiation.

    PubMed

    Laperre, Jan; Foubert, Fred

    2002-01-01

    The first European standard which describes the test procedure to determine the UV-protection factor of clothing is about to be completed. A second part of the same standard, dealing with labelling and marking aspects, is ready to be submitted to public enquiry. In this effort a group of experts from most EU member states have cooperated with a high degree of consensus. In this chapter we explain this European standard together with the standard developed in the UK. PMID:12079233

  11. Provisional standards of radiation safety of flight personnel and passengers in air transport of the civil aviation

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Provisional standards for radiation affecting passenger aircraft are considered. Agencies responsible for seeing that the regulations are enforced are designated while radiation sources and types of radiation are defined. Standard levels of permissible radiation are given and conditions for radiation safety are discussed. Dosimetric equipment on board aircraft is delineated and regulation effective dates are given.

  12. Complex Squeezing and Force Measurement Beyond the Standard Quantum Limit.

    PubMed

    Buchmann, L F; Schreppler, S; Kohler, J; Spethmann, N; Stamper-Kurn, D M

    2016-07-15

    A continuous quantum field, such as a propagating beam of light, may be characterized by a squeezing spectrum that is inhomogeneous in frequency. We point out that homodyne detectors, which are commonly employed to detect quantum squeezing, are blind to squeezing spectra in which the correlation between amplitude and phase fluctuations is complex. We find theoretically that such complex squeezing is a component of ponderomotive squeezing of light through cavity optomechanics. We propose a detection scheme called synodyne detection, which reveals complex squeezing and allows the accounting of measurement backaction. Even with the optomechanical system subject to continuous measurement, such detection allows the measurement of one component of an external force with sensitivity only limited by the mechanical oscillator's thermal occupation. PMID:27472106

  13. Complex Squeezing and Force Measurement Beyond the Standard Quantum Limit

    NASA Astrophysics Data System (ADS)

    Buchmann, L. F.; Schreppler, S.; Kohler, J.; Spethmann, N.; Stamper-Kurn, D. M.

    2016-07-01

    A continuous quantum field, such as a propagating beam of light, may be characterized by a squeezing spectrum that is inhomogeneous in frequency. We point out that homodyne detectors, which are commonly employed to detect quantum squeezing, are blind to squeezing spectra in which the correlation between amplitude and phase fluctuations is complex. We find theoretically that such complex squeezing is a component of ponderomotive squeezing of light through cavity optomechanics. We propose a detection scheme called synodyne detection, which reveals complex squeezing and allows the accounting of measurement backaction. Even with the optomechanical system subject to continuous measurement, such detection allows the measurement of one component of an external force with sensitivity only limited by the mechanical oscillator's thermal occupation.

  14. The Locust Standard Brain: A 3D Standard of the Central Complex as a Platform for Neural Network Analysis

    PubMed Central

    el Jundi, Basil; Heinze, Stanley; Lenschow, Constanze; Kurylas, Angela; Rohlfing, Torsten; Homberg, Uwe

    2009-01-01

    Many insects use the pattern of polarized light in the sky for spatial orientation and navigation. We have investigated the polarization vision system in the desert locust. To create a common platform for anatomical studies on polarization vision pathways, Kurylas et al. (2008) have generated a three-dimensional (3D) standard brain from confocal microscopy image stacks of 10 male brains, using two different standardization methods, the Iterative Shape Averaging (ISA) procedure and the Virtual Insect Brain (VIB) protocol. Comparison of both standardization methods showed that the VIB standard is ideal for comparative volume analysis of neuropils, whereas the ISA standard is the method of choice to analyze the morphology and connectivity of neurons. The central complex is a key processing stage for polarization information in the locust brain. To investigate neuronal connections between diverse central-complex neurons, we generated a higher-resolution standard atlas of the central complex and surrounding areas, using the ISA method based on brain sections from 20 individual central complexes. To explore the usefulness of this atlas, two central-complex neurons, a polarization-sensitive columnar neuron (type CPU1a) and a tangential neuron that is activated during flight, the giant fan-shaped (GFS) neuron, were reconstructed 3D from brain sections. To examine whether the GFS neuron is a candidate to contribute to synaptic input to the CPU1a neuron, we registered both neurons into the standardized central complex. Visualization of both neurons revealed a potential connection of the CPU1a and GFS neurons in layer II of the upper division of the central body. PMID:20161763

  15. Radiation scales on which standard values of the solar constant and solar spectral irradiance are based

    NASA Technical Reports Server (NTRS)

    Thekaekara, M. P.

    1972-01-01

    The question of radiation scales is critically examined. There are two radiation scales which are of fundamental validity and there are several calibration standards and radiation scales which have been set up for practical convenience. The interrelation between these scales is investigated. It is shown that within the limits of accuracy of irradiance measurements in general and solar irradiance measurements in particular, the proposed standard values of the solar constant and solar spectrum should be considered to be on radiation scales of fundamental validity; those based on absolute electrical units and on the thermodynamic Kelvin temperature scale.

  16. Radiation standards and calibrations. FY-1981 annual report

    SciTech Connect

    Roberson, P.L.; Yoder, R.C.; Fox, R.A.; Hooker, C.D.; Hogan, R.T.; Holbrook, K.L.; Hadley, R.T.

    1982-07-01

    The research program encompasses: reviewing calibration standards, regulations, and handbooks; assuring that calibration procedures used are in agreement with technically accepted methods; maintaining basic radioactive sources and instruments that serve as radiological standards; and providing traceability to the National Bureau of Standards where possible. In addition, major efforts are being expended to upgrade the 318 calibration facility. This report focuses on major accomplishments during FY-1981. However, most maintenance and quality assurance efforts involve routine support and only a summary report is provided. (PSB)

  17. Regional cancer centre demonstrates voluntary conformity with the national Radiation Oncology Practice Standards

    SciTech Connect

    Manley, Stephen Last, Andrew; Fu, Kenneth; Greenham, Stuart; Kovendy, Andrew; Shakespeare, Thomas P

    2015-06-15

    Radiation Oncology Practice Standards have been developed over the last 10 years and were published for use in Australia in 2011. Although the majority of the radiation oncology community supports the implementation of the standards, there has been no mechanism for uniform assessment or governance. North Coast Cancer Institute's public radiation oncology service is provided across three main service centres on the north coast of NSW. With a strong focus on quality management, we embraced the opportunity to demonstrate conformity with the Radiation Oncology Practice Standards. The Local Health District's Clinical Governance units were engaged to perform assessments of our conformity with the standards and this was signed off as complete on 16 December 2013. The process of demonstrating conformity with the Radiation Oncology Practice Standards has enhanced the culture of quality in our centres. We have demonstrated that self-assessment utilising trained auditors is a viable method for centres to demonstrate conformity. National implementation of the Radiation Oncology Practice Standards will benefit individual centres and the broader radiation oncology community to improve the service delivered to our patients.

  18. Regional cancer centre demonstrates voluntary conformity with the national Radiation Oncology Practice Standards

    PubMed Central

    Manley, Stephen; Last, Andrew; Fu, Kenneth; Greenham, Stuart; Kovendy, Andrew; Shakespeare, Thomas P

    2015-01-01

    Radiation Oncology Practice Standards have been developed over the last 10 years and were published for use in Australia in 2011. Although the majority of the radiation oncology community supports the implementation of the standards, there has been no mechanism for uniform assessment or governance. North Coast Cancer Institute's public radiation oncology service is provided across three main service centres on the north coast of NSW. With a strong focus on quality management, we embraced the opportunity to demonstrate conformity with the Radiation Oncology Practice Standards. The Local Health District's Clinical Governance units were engaged to perform assessments of our conformity with the standards and this was signed off as complete on 16 December 2013. The process of demonstrating conformity with the Radiation Oncology Practice Standards has enhanced the culture of quality in our centres. We have demonstrated that self-assessment utilising trained auditors is a viable method for centres to demonstrate conformity. National implementation of the Radiation Oncology Practice Standards will benefit individual centres and the broader radiation oncology community to improve the service delivered to our patients. PMID:26229680

  19. US Department of Energy standardized radiation safety training

    SciTech Connect

    Trinoskey, P.A.

    1997-02-01

    The following working groups were formed under the direction of a radiological training coordinator: managers, supervisors, DOE auditors, ALARA engineers/schedulers/planners, radiological control personnel, radiation-generating device operators, emergency responders, visitors, Pu facilities, U facilities, tritium facilities, accelerator facilities, biomedical researchers. General courses for these groups are available, now or soon, in the form of handbooks.

  20. Cost Accounting Standards: An Overview of Compliance with These Complex Standards.

    ERIC Educational Resources Information Center

    Bruce, Janet D.

    1993-01-01

    A discussion of federal cost accounting standards (CAS) chronicles briefly the history of CAS, notes other pertinent regulations applicable to higher education, summarizes the initial standards drafted for colleges and universities, and examines disclosure statement requirements and implications of noncompliance. (MSE)

  1. Radiation of complex and noisy sources within enclosures

    NASA Astrophysics Data System (ADS)

    Gradoni, Gabriele; Creagh, Stephen; Tanner, Gregor

    Predicting the radiation of complex electromagnetic sources inside semi-open cavities and resonators with arbitrary geometry is a challenging topic both for physics and for engineering. We have exploited a Perron-Frobenius operator to propagate field-field correlation functions of complex and extended sources in free-space. The formula is based on a phase-space picture of the electromagnetic field, using the Wigner distribution function, and naturally captures evanescent as well as diffracted waves. This approach can be extended to study the propagation of correlation functions within cavities, with the ray-dynamical map given by the geometry of the cord connecting a point of the boundary to another. While ray methods provide an efficient way to predict average values of the correlation matrix elements, the use of random matrix theory approaches allows efficient characterisation of statistical fluctuations around these averages. Universal relations are derived and tested in the presence of dissipation for quantum maps and billiard systems. The use of this formalism is discussed in the contexts of open systems with surface roughness. The theory and achieved results are of interest in the simulation of next-generation of wireless communications. Work supported by the UK Engineering and Physical Sciences Research Council.

  2. EVOLUTION OF THE IEC AND EN STANDARDS FOR INDIVIDUAL MONITORING OF IONISING RADIATION.

    PubMed

    Voytchev, M; Behrens, R; Ambrosi, P; Radev, R; Chiaro, P

    2016-09-01

    This article presents the evolution of the International Electrotechnical Commission (IEC) and the European standards for individual monitoring of ionising radiation issued, respectively, from the committees IEC/Sub Committee 45B and European Committee for Electro-technical Standardization/Technical Committee 45B 'Radiation protection instrumentation'. Standards for passive individual photon and beta dosimetry systems as well as those for active individual monitors are discussed. A neutron ambient dose equivalent (rate) meter standard and a technical report concerning the determination of uncertainty in measurement are also covered. PMID:26443545

  3. Standard Model Treatment of the Radiative Corrections to Neutron β-Decay

    PubMed Central

    Bunatian, G. G.

    2005-01-01

    Starting with the Standard Model electroweak Lagrangian, the radiative corrections to neutron β-decay are obtained. Nucleon compositeness is considered by appropriate parameterization of the nucleon weak transition current and electromagnetic form factors. PMID:27308144

  4. Standard Practice for Dosimetry of Proton Beams for use in Radiation Effects Testing of Electronics

    SciTech Connect

    McMahan, Margaret A.; Blackmore, Ewart; Cascio, Ethan W.; Castaneda, Carlos; von Przewoski, Barbara; Eisen, Harvey

    2008-07-25

    Representatives of facilities that routinely deliver protons for radiation effect testing are collaborating to establish a set of standard best practices for proton dosimetry. These best practices will be submitted to the ASTM International for adoption.

  5. Radiation Standards: The Last Word or at Least a Definitive One

    ERIC Educational Resources Information Center

    Gillette, Robert

    1972-01-01

    Discusses the report of the National Academy of Science Committee on the Biological Effects of Ionizing Radiation, with particular reference to the possibilities for lowering maximum permissible standards for exposure to man-made radiation. The excessive use of diagnostic X-rays is considered. (AL)

  6. Modelling radiation fluxes in simple and complex environments—application of the RayMan model

    NASA Astrophysics Data System (ADS)

    Matzarakis, Andreas; Rutz, Frank; Mayer, Helmut

    2007-03-01

    The most important meteorological parameter affecting the human energy balance during sunny weather conditions is the mean radiant temperature Tmrt. It considers the uniform temperature of a surrounding surface giving off blackbody radiation, which results in the same energy gain of a human body given the prevailing radiation fluxes. This energy gain usually varies considerably in open space conditions. In this paper, the model ‘RayMan’, used for the calculation of short- and long-wave radiation fluxes on the human body, is presented. The model, which takes complex urban structures into account, is suitable for several applications in urban areas such as urban planning and street design. The final output of the model is, however, the calculated Tmrt, which is required in the human energy balance model, and thus also for the assessment of the urban bioclimate, with the use of thermal indices such as predicted mean vote (PMV), physiologically equivalent temperature (PET) and standard effective temperature (SET*). The model has been developed based on the German VDI-Guidelines 3789, Part II (environmental meteorology, interactions between atmosphere and surfaces; calculation of short- and long-wave radiation) and VDI-3787 (environmental meteorology, methods for the human-biometeorological evaluation of climate and air quality for urban and regional planning. Part I: climate). The validation of the results of the RayMan model agrees with similar results obtained from experimental studies.

  7. Radiation Observations from CREAM & CREDO and Comparison with Standard Models

    NASA Astrophysics Data System (ADS)

    Dyer, C.; Watson, C.; Truscott, P.; Peerless, C.

    1996-12-01

    The Cosmic Radiation Environment and Activation Monitor (CREAM) has flown on six Shuttle flights between September 1991 and February 1995, covering the full range of inclinations as well as altitudes between 210 and 550 km. Meanwhile the Cosmic Radiation Environment and Dosimetry experiment (CREDO) has operated continuously on UOSAT-3 in 800 km, 98.7 degree orbit since April 1990. Similar detectors were launched on KITSAT-1 (1330 km, 66 degree inclination) in August 1992 and POSAT-l (790 km, 98.7 degree inclination) in September 1993. Since the summer of 1994, CREDO-II versions have been operating on APEX in an eccentric orbit (350x2486 km) at 70 degree inclination, and on STRV in geostationary transfer orbit (298x35953 km, 7 degree inclination). These experiments are designed to measure protons, cosmic rays and accumulated dose. Through the variety of missions employed they have now achieved wide coverage of the magnetosphere as well as a significant portion of a solar cycle. The LEO observations have shown the Westward drift of the South Atlantic Anomaly, new regimes of trapped protons in the region of L=2.6 following solar flare events in March 1991 and October 1992, and an altitude dependence of trapped protons which is at variance with AP8. On STRV the background channel of the Cold Ion Detector serves as a complementary electron detector and shows the extreme time variability of the outer radiation belt, while the total dose is significantly less than AE8 predictions. In addition to the data on trapped radiation, important results are being obtained on the linear energy transfer spectra from cosmic rays. Detailed shielding models of the APEX and STRV spacecraft have been constructed and used to compare the observations of dose and LET spectra with predictions from AE8, AP8 and CREME for a variety of shielding depths. Consistent results on the LET spectra are obtained from APEX and STRV when data are selected by cut-off rigidity. The influence of spacecraft

  8. Blackbody radiation shift in the {sup 87}Rb frequency standard

    SciTech Connect

    Safronova, M. S.; Jiang Dansha; Safronova, U. I.

    2010-08-15

    The operation of atomic clocks is generally carried out at room temperature, whereas the definition of the second refers to the clock transition in an atom at absolute zero. This implies that the clock transition frequency should be corrected in practice for the effect of finite temperature, of which the leading contributor is the blackbody radiation (BBR) shift. Experimental measurements of the BBR shifts are difficult. In this work, we have calculated the blackbody radiation shift of the ground-state hyperfine microwave transition in {sup 87}Rb using the relativistic all-order method and carried out a detailed evaluation of the accuracy of our final value. Particular care is taken to accurately account for the contributions from highly excited states. Our predicted value for the Stark coefficient, k{sub S}=-1.240(4)x10{sup -10} Hz/(V/m){sup 2}, is three times more accurate than the previous calculation [E. J. Angstman, V. A. Dzuba, and V. V. Flambaum, Phys. Rev. A 74, 023405 (2006)].

  9. Progress on standardization of electron beam dosimetry for radiation processing

    NASA Astrophysics Data System (ADS)

    Chenghua, Li; Yanli, Zhang; Ruicao, Pang; Zhimian, Liu; Xuan, Xia; Jingmin, Wu

    1993-10-01

    The high dose standards and dissemination system of electron beams are being established at NIM. The graphite and/ or water calorimeters and liquid chemical dosimeter are to be accepted as standards. The transfer dosimeter selected are alanine/ESR dosimeter and radiochromic film (FWT - 60). Several kinds of radiochromic films, undyed cellulose triacetate, polyethylene and blue cellophane will be recommended as working dosimeter. A series of intercomparison studies are conducted between calorimeter and dichromate dosimeter. Agreement is found within 2%. Water calorimeters and dichromate dosimeters are used to make absolute dosimetric measurements of electron beams. These calibrated beams are then used to calibrate several types of dosimeters, such as alanine, radiochromic films, undyed and dyed polyethylene. Preliminary studies show that water calorimeter and dichromate dosimeter are reproducible and sufficiently accurate for electron beam calibration. The estimated overall uncertainty of the measurement is better than 5% at 95% confidence level.

  10. Standard descriptive nomenclature of constituents of aggregates for radiation-shielding concrete. ASTM standard

    SciTech Connect

    1992-05-01

    This nomenclature is under the jurisdiction of ASTM Committee C-9 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.41 on Concrete for Radiation Shielding. Current edition approved Mar. 15, 1992 and published May 1992. Originally published as C 638-73. Last previous edition was C 638-84(1990). It was reapproved 1997.

  11. Modernisation and consolidation of the European radiation protection legislation: the new Euratom Basic Safety Standards Directive.

    PubMed

    Mundigl, Stefan

    2015-04-01

    With the publication of new basic safety standards for the protection against the dangers arising from exposure to ionising radiation, foreseen in Article 2 and Article 30 of the Euratom Treaty, the European Commission modernises and consolidates the European radiation protection legislation. A revision of the Basic Safety Standards was needed in order (1) to take account of the scientific and technological progress since 1996 and (2) to consolidate the existing set of Euratom radiation protection legislation, merging five Directives and upgrading a recommendation to become legally binding. The new Directive offers in a single coherent document basics safety standards for radiation protection, which take account of the most recent advances in science and technology, cover all relevant radiation sources, including natural radiation sources, integrate protection of workers, members of the public, patients and the environment, cover all exposure situations, planned, existing, emergency, and harmonise numerical values with international standards. After the publication of the Directive in the beginning of 2014, Member States have 4 y to transpose the Directive into national legislation and to implement the requirements therein. PMID:25227437

  12. Generating Automated Text Complexity Classifications That Are Aligned with Targeted Text Complexity Standards. Research Report. ETS RR-10-28

    ERIC Educational Resources Information Center

    Sheehan, Kathleen M.; Kostin, Irene; Futagi, Yoko; Flor, Michael

    2010-01-01

    The Common Core Standards call for students to be exposed to a much greater level of text complexity than has been the norm in schools for the past 40 years. Textbook publishers, teachers, and assessment developers are being asked to refocus materials and methods to ensure that students are challenged to read texts at steadily increasing…

  13. Challenging the Research Base of the Common Core State Standards: A Historical Reanalysis of Text Complexity

    ERIC Educational Resources Information Center

    Gamson, David A.; Lu, Xiaofei; Eckert, Sarah Anne

    2013-01-01

    The widely adopted Common Core State Standards (CCSS) call for raising the level of text complexity in textbooks and reading materials used by students across all grade levels in the United States; the authors of the English Language Arts component of the CCSS build their case for higher complexity in part upon a research base they say shows a…

  14. Complex Text and New Common Standards in the United States: Pedagogical Implications for English Learners

    ERIC Educational Resources Information Center

    Bunch, George C.; Walqui, Aída; Pearson, P. David

    2014-01-01

    In the United States, new common state standards in English language arts and disciplinary literacy require K-12 students to "read and comprehend complex literary and informational texts independently and proficiently." Issues of text complexity have spurred debates in the mainstream literacy, educational practice, and policy…

  15. Explicit validation of a surface shortwave radiation balance model over snow-covered complex terrain

    NASA Astrophysics Data System (ADS)

    Helbig, N.; Löwe, H.; Mayer, B.; Lehning, M.

    2010-09-01

    A model that computes the surface radiation balance for all sky conditions in complex terrain is presented. The spatial distribution of direct and diffuse sky radiation is determined from observations of incident global radiation, air temperature, and relative humidity at a single measurement location. Incident radiation under cloudless sky is spatially derived from a parameterization of the atmospheric transmittance. Direct and diffuse sky radiation for all sky conditions are obtained by decomposing the measured global radiation value. Spatial incident radiation values under all atmospheric conditions are computed by adjusting the spatial radiation values obtained from the parametric model with the radiation components obtained from the decomposition model at the measurement site. Topographic influences such as shading are accounted for. The radiosity approach is used to compute anisotropic terrain reflected radiation. Validations of the shortwave radiation balance model are presented in detail for a day with cloudless sky. For a day with overcast sky a first validation is presented. Validation of a section of the horizon line as well as of individual radiation components is performed with high-quality measurements. A new measurement setup was designed to determine terrain reflected radiation. There is good agreement between the measurements and the modeled terrain reflected radiation values as well as with incident radiation values. A comparison of the model with a fully three-dimensional radiative transfer Monte Carlo model is presented. That validation reveals a good agreement between modeled radiation values.

  16. Radon in the Workplace: the Occupational Safety and Health Administration (OSHA) Ionizing Radiation Standard.

    PubMed

    Lewis, Robert K

    2016-10-01

    On 29 December 1970, the Occupational Safety and Health Act of 1970 established the Occupational Safety and Health Administration (OSHA). This article on OSHA, Title 29, Part 1910.1096 Ionizing Radiation standard was written to increase awareness of the employer, the workforce, state and federal governments, and those in the radon industry who perform radon testing and radon mitigation of the existence of these regulations, particularly the radon relevant aspect of the regulations. This review paper was also written to try to explain what can sometimes be complicated regulations. As the author works within the Radon Division of the Pennsylvania Department of Environmental Protection, Bureau of Radiation Protection, the exclusive focus of the article is on radon. The 1910.1096 standard obviously covers many other aspects of radiation and radiation safety in the work place. PMID:27575350

  17. Feasibility of EBT Gafchromic films for comparison exercises among standard beta radiation fields.

    PubMed

    Benavente, J A; Meira-Belo, L C; Reynaldo, S R; da Silva, T A

    2012-12-01

    The feasibility of using radiochromic films to verify the metrological coherence among standard beta radiation fields was evaluated. Exercises were done between two Brazilian metrology laboratories in beta fields from (90)Sr/(90)Y, (85)Kr and (147)Pm radiation sources. Results showed that the radiochromic film was useful for field mapping aiming uniformity and alignment verification and it was not reliable for absorbed dose measurements only for (147)Pm beta field. PMID:22917942

  18. Cosmic strings in hidden sectors: 1. Radiation of standard model particles

    SciTech Connect

    Long, Andrew J.; Hyde, Jeffrey M.; Vachaspati, Tanmay E-mail: jmhyde@asu.edu

    2014-09-01

    In hidden sector models with an extra U(1) gauge group, new fields can interact with the Standard Model only through gauge kinetic mixing and the Higgs portal. After the U(1) is spontaneously broken, these interactions couple the resultant cosmic strings to Standard Model particles. We calculate the spectrum of radiation emitted by these ''dark strings'' in the form of Higgs bosons, Z bosons, and Standard Model fermions assuming that string tension is above the TeV scale. We also calculate the scattering cross sections of Standard Model fermions on dark strings due to the Aharonov-Bohm interaction. These radiation and scattering calculations will be applied in a subsequent paper to study the cosmological evolution and observational signatures of dark strings.

  19. Visualization of a Deterministic Radiation Transport Model Using Standard Visualization Tools

    SciTech Connect

    James A. Galbraith; L. Eric Greenwade

    2004-05-01

    Output from a deterministic radiation transport code running on a CRAY SV1 is imported into a standard distributed, parallel, visualization tool for analysis. Standard output files, consisting of tetrahedral meshes, are imported to the visualization tool through the creation of a application specific plug-in module. Visualization samples are included, providing visualization of steady state results. Different plot types and operators are utilized to enhance the analysis and assist in reporting the results of the analysis.

  20. Radiation increases the cellular uptake of exosomes through CD29/CD81 complex formation

    SciTech Connect

    Hazawa, Masaharu; Tomiyama, Kenichi; Saotome-Nakamura, Ai; Obara, Chizuka; Yasuda, Takeshi; Gotoh, Takaya; Tanaka, Izumi; Yakumaru, Haruko; Ishihara, Hiroshi; Tajima, Katsushi

    2014-04-18

    Highlights: • Radiation increases cellular uptake of exosomes. • Radiation induces colocalization of CD29 and CD81. • Exosomes selectively bind the CD29/CD81 complex. • Radiation increases the cellular uptake of exosomes through CD29/CD81 complex formation. - Abstract: Exosomes mediate intercellular communication, and mesenchymal stem cells (MSC) or their secreted exosomes affect a number of pathophysiologic states. Clinical applications of MSC and exosomes are increasingly anticipated. Radiation therapy is the main therapeutic tool for a number of various conditions. The cellular uptake mechanisms of exosomes and the effects of radiation on exosome–cell interactions are crucial, but they are not well understood. Here we examined the basic mechanisms and effects of radiation on exosome uptake processes in MSC. Radiation increased the cellular uptake of exosomes. Radiation markedly enhanced the initial cellular attachment to exosomes and induced the colocalization of integrin CD29 and tetraspanin CD81 on the cell surface without affecting their expression levels. Exosomes dominantly bound to the CD29/CD81 complex. Knockdown of CD29 completely inhibited the radiation-induced uptake, and additional or single knockdown of CD81 inhibited basal uptake as well as the increase in radiation-induced uptake. We also examined possible exosome uptake processes affected by radiation. Radiation-induced changes did not involve dynamin2, reactive oxygen species, or their evoked p38 mitogen-activated protein kinase-dependent endocytic or pinocytic pathways. Radiation increased the cellular uptake of exosomes through CD29/CD81 complex formation. These findings provide essential basic insights for potential therapeutic applications of exosomes or MSC in combination with radiation.

  1. 21 CFR 14.120 - Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Establishment of the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC). 14.120 Section 14.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PUBLIC HEARING BEFORE A PUBLIC ADVISORY COMMITTEE Technical Electronic...

  2. Measurement and standardization of eye safety for optical radiation of LED products

    NASA Astrophysics Data System (ADS)

    Mou, Tongsheng; Peng, Zhenjian

    2013-06-01

    The blue light hazard (BLH) to human eye's retina is now a new issue emerging in applications of artificial light sources. Especially for solid state lighting sources based on the blue chip-LED(GaN), the photons with their energy more than 2.4 eV show photochemical effects on the retina significantly, raising damage both in photoreceptors and retinal pigment epithelium. The photobiological safety of artificial light sources emitting optical radiation has gained more and more attention worldwide and addressed by international standards IEC 62471-2006(CIE S009/E: 2002). Meanwhile, it is involved in IEC safety specifications of LED lighting products and covered by European Directive 2006/25/EC on the minimum health and safety requirements regarding the exposure of the workers to artificial optical radiation. In practical applications of the safety standards, the measuring methods of optical radiation from LED products to eyes are important in establishment of executable methods in the industry. In 2011, a new project to develop the international standard of IEC TR62471-4,that is "Measuring methods of optical radiation related to photobiological safety", was approved and are now under way. This paper presents the concerned methods for the assessment of optical radiation hazards in the standards. Furthermore, a retina radiance meter simulating eye's optical geometry is also described, which is a potential tool for blue light hazard assessment of retinal exposure to optical radiation. The spectroradiometric method integrated with charge-coupled device(CCD) imaging system is introduced to provide more reliable results.

  3. Standard thermodynamic functions of Co2+ complexation with glycine and L-histidine in aqueous solution

    NASA Astrophysics Data System (ADS)

    Gorboletova, G. G.; Metlin, A. A.

    2016-02-01

    The enthalpies of the reactions between solutions of Co(NO3)2 and solutions of glycine (Gly) and L-histidine (His) are determined via direct calorimetry at different pH values and metal: ligand ratios using KNO3 as a background electrolyte ( T = 298.15 K, I = 0.2-1.0). The enthalpy changes upon the formation of cobalt glycinate complexes and Co2+ mixed-ligand complex, viz., glycine-L-histidine, were calculated. The standard thermodynamic parameters (Δr H°, Δr G°, Δr S°) of complexation are determined. The CoGlyHis complex is shown to be stable toward decomposition into homogeneous complexes.

  4. The Relationship between Students' Performance on Conventional Standardized Mathematics Assessments and Complex Mathematical Modeling Problems

    ERIC Educational Resources Information Center

    Kartal, Ozgul; Dunya, Beyza Aksu; Diefes-Dux, Heidi A.; Zawojewski, Judith S.

    2016-01-01

    Critical to many science, technology, engineering, and mathematics (STEM) career paths is mathematical modeling--specifically, the creation and adaptation of mathematical models to solve problems in complex settings. Conventional standardized measures of mathematics achievement are not structured to directly assess this type of mathematical…

  5. Standardization Process for Space Radiation Models Used for Space System Design

    NASA Technical Reports Server (NTRS)

    Barth, Janet; Daly, Eamonn; Brautigam, Donald

    2005-01-01

    The space system design community has three concerns related to models of the radiation belts and plasma: 1) AP-8 and AE-8 models are not adequate for modern applications; 2) Data that have become available since the creation of AP-8 and AE-8 are not being fully exploited for modeling purposes; 3) When new models are produced, there is no authorizing organization identified to evaluate the models or their datasets for accuracy and robustness. This viewgraph presentation provided an overview of the roadmap adopted by the Working Group Meeting on New Standard Radiation Belt and Space Plasma Models.

  6. Development of a proposed international standard for certification of aircraft to High Intensity Radiated Fields (HIRF)

    NASA Technical Reports Server (NTRS)

    Sargent, Noel B.

    1993-01-01

    Avionic systems performing critical functions in modern aircraft are potentially susceptible to the hazards of electromagnetic radiation from ground and airborne transmitters. The Federal Aviation Administration (FAA) requested that the Society of Automotive Engineers (SAE) coordinate the development of procedures and guidance material which can be used during the aircraft certification process to ensure adequate protection against high intensity radiated fields (HIRF). This paper addresses both the technical challenge of drafting a certification procedure and guidance standard as well as the management process used by the SAE subcommittee AE4R to converge a diverse range of opinions by its international membership in the shortest possible time.

  7. Standard thermodynamic functions of complex formation between Cu2+ and glycine in aqueous solution

    NASA Astrophysics Data System (ADS)

    Gorboletova, G. G.; Metlin, A. A.

    2013-05-01

    Heat effects of the interaction of copper(II) solutions with aminoacetic acid (glycine) are measured by the direct calorimetry at 298.15 K and ionic strengths of 0.5, 1.0, and 1.5 against a background of potassium nitrate. Standard enthalpy values for reactions of the formation of aminoacetic acid copper complexes in aqueous solutions are obtained using an equation with a single individual parameter by extrapolating it to zero ionic strength. The standard thermodynamic characteristics of complex formation in the Cu2+-glycine system are calculated. It is shown that glycine-like coordination is most likely in Cu(II) complexes with L-asparagine, L-glutamine, and L-valine.

  8. Preparation and characterization of standardized pomegranate extract-phospholipid complex as an effective drug delivery tool

    PubMed Central

    Vora, Amisha Kamlesh; Londhe, Vaishali Y.; Pandita, Nancy S.

    2015-01-01

    Punicalagins, a pair of anomeric ellagitannins, present in Punica granatum (Pomegranates) are known to possess excellent antioxidant activity in vitro, but poor oral bioavailability. The reasons cited for poor bioavailability are their large molecular size, poor lipophilicity, and degradation by colonic microflora into less active metabolites. The objective of the present research work was to complex the standardized pomegranate extract (SPE) with phospholipid to formulate standardized pomegranate extract-phospholipid complex (SPEPC), characterize it and check its permeability through an ex vivo everted gut sac experiment. SPEPC was prepared by mixing SPE (30% punicalagins) and soya phosphatidylcholine (PC) in 1:1 v/v mixture of methanol and dioxane and spray-drying the mixture. The complex was characterized by infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. It was evaluated for its octanol solubility, dissolution, and permeability by everted the gut sac technique. The characterization methods confirmed the formation of complex. Increased n-octanol solubility of the complex proved its increased lipophilicity. Dissolution studies revealed that the phospholipid covering may prevent the punicalagins to be released in gastro-intestinal tract, thus preventing their colonic microbial degradation. SPEPC showed better apparent permeability than SPE in an everted gut sac technique. Hence, it could be concluded that phospholipid complex of SPE may be of potential use in increasing the permeability and hence the bioavailability of punicalagins. PMID:25878977

  9. Atomic and Molecular Complex Resonances from Real Eigenvalues Using Standard (Hermitian) Electronic Structure Calculations.

    PubMed

    Landau, Arie; Haritan, Idan; Kaprálová-Žd'ánská, Petra Ruth; Moiseyev, Nimrod

    2016-05-19

    Complex eigenvalues, resonances, play an important role in a large variety of fields in physics and chemistry. For example, in cold molecular collision experiments and electron scattering experiments, autoionizing and predissociative metastable resonances are generated. However, the computation of complex resonance requires modifications of standard electronic structure codes and methods, which are not always straightforward, in addition, application of complex codes requires more computational efforts. Here we show how resonance eigenvalues, positions and widths, can be calculated using the standard, widely used, electronic-structure packages. Our method enables the calculations of the complex resonance eigenvalues by using analytical continuation procedures (such as Padé). The key point in our approach is the existence of narrow analytical passages from the real axis to the complex energy plane. In fact, the existence of these analytical passages relies on using finite basis sets. These passages become narrower as the basis set becomes more complete, whereas in the exact limit, these passages to the complex plane are closed. As illustrative numerical examples we calculated the autoionization Feshbach resonances of helium, hydrogen anion, and hydrogen molecule. We show that our results are in an excellent agreement with the results obtained by other theoretical methods and with available experimental results. PMID:26677725

  10. Preparation and characterization of standardized pomegranate extract-phospholipid complex as an effective drug delivery tool.

    PubMed

    Vora, Amisha Kamlesh; Londhe, Vaishali Y; Pandita, Nancy S

    2015-01-01

    Punicalagins, a pair of anomeric ellagitannins, present in Punica granatum (Pomegranates) are known to possess excellent antioxidant activity in vitro, but poor oral bioavailability. The reasons cited for poor bioavailability are their large molecular size, poor lipophilicity, and degradation by colonic microflora into less active metabolites. The objective of the present research work was to complex the standardized pomegranate extract (SPE) with phospholipid to formulate standardized pomegranate extract-phospholipid complex (SPEPC), characterize it and check its permeability through an ex vivo everted gut sac experiment. SPEPC was prepared by mixing SPE (30% punicalagins) and soya phosphatidylcholine (PC) in 1:1 v/v mixture of methanol and dioxane and spray-drying the mixture. The complex was characterized by infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. It was evaluated for its octanol solubility, dissolution, and permeability by everted the gut sac technique. The characterization methods confirmed the formation of complex. Increased n-octanol solubility of the complex proved its increased lipophilicity. Dissolution studies revealed that the phospholipid covering may prevent the punicalagins to be released in gastro-intestinal tract, thus preventing their colonic microbial degradation. SPEPC showed better apparent permeability than SPE in an everted gut sac technique. Hence, it could be concluded that phospholipid complex of SPE may be of potential use in increasing the permeability and hence the bioavailability of punicalagins. PMID:25878977

  11. Methods of treating complex space vehicle geometry for charged particle radiation transport

    NASA Technical Reports Server (NTRS)

    Hill, C. W.

    1973-01-01

    Current methods of treating complex geometry models for space radiation transport calculations are reviewed. The geometric techniques used in three computer codes are outlined. Evaluations of geometric capability and speed are provided for these codes. Although no code development work is included several suggestions for significantly improving complex geometry codes are offered.

  12. Toxic variability and radiation potentiation by Rh(III) complexes in Salmonella typhimurium cells

    SciTech Connect

    Richmond, R.C.; O'Hara, J.; Picker, D.H.; Douple, E.B.

    1986-12-01

    Stationary-phase cells of Salmonella typhimurium were irradiated in phosphate-buffered saline in the presence of rhodium complexes to test for the potentiation of radiation-induced cell killing. Eleven Rh complexes, two Rh(I) and nine Rh(III), were tested. Seven Rh(III) complexes were found to be radiation potentiators; six potentiate only under hypoxic conditions, and one potentiates under both hypoxic and oxic conditions. Four of these seven Rh(III) complexes demonstrate potentiation that is 2 to 13 times greater than the sensitization caused by oxygen. Irradiating cells in Ham's F-12 culture medium rather than in phosphate-buffered saline eliminates this latter hypoxic radiation potentiation. None of the seven Rh(III) radiation potentiators are directly toxic to cells. However, four complexes were tested for hypoxic radiation-induced cytocidal toxicity, and three were found to be toxic after irradiation. The efficiency of this toxicity is not sufficient to account for the observed radiation potentiation. It is suggested that both reductive and oxidative free radical events are involved in the spectrum of Rh(III) potentiation observed.

  13. Impact of complexity and computer control on errors in radiation therapy.

    PubMed

    Fraass, B A

    2012-01-01

    A number of recent publications in both the lay and scientific press have described major errors in patient radiation treatments, and this publicity has galvanised much work to address and mitigate potential safety issues throughout the radiation therapy planning and delivery process. The complexity of modern radiotherapy techniques and equipment, including computer-controlled treatment machines and treatment management systems, as well as sophisticated treatment techniques that involve intensity-modulated radiation therapy, image-guided radiation therapy, stereotactic body radiation therapy, volumetric modulated arc therapy, respiratory gating, and others, leads to concern about safety issues related to that complexity. This article illustrates the relationship between complexity and computer control, and various safety problems and errors that have been reported, and describes studies that address the issue of these modern techniques and whether their complexity does, in fact, result in more errors or safety-related problems. Clinical implications of these results are discussed, as are some of the ways in which the field should respond to the ongoing concerns about errors and complexity in radiation therapy. PMID:23089018

  14. RIP1 and RIP3 complex regulates radiation-induced programmed necrosis in glioblastoma.

    PubMed

    Das, Arabinda; McDonald, Daniel G; Dixon-Mah, Yaenette N; Jacqmin, Dustin J; Samant, Vikram N; Vandergrift, William A; Lindhorst, Scott M; Cachia, David; Varma, Abhay K; Vanek, Kenneth N; Banik, Naren L; Jenrette, Joseph M; Raizer, Jeffery J; Giglio, Pierre; Patel, Sunil J

    2016-06-01

    Radiation-induced necrosis (RN) is a relatively common side effect of radiation therapy for glioblastoma. However, the molecular mechanisms involved and the ways RN mechanisms differ from regulated cell death (apoptosis) are not well understood. Here, we compare the molecular mechanism of cell death (apoptosis or necrosis) of C6 glioma cells in both in vitro and in vivo (C6 othotopically allograft) models in response to low and high doses of X-ray radiation. Lower radiation doses were used to induce apoptosis, while high-dose levels were chosen to induce radiation necrosis. Our results demonstrate that active caspase-8 in this complex I induces apoptosis in response to low-dose radiation and inhibits necrosis by cleaving RIP1 and RI. When activation of caspase-8 was reduced at high doses of X-ray radiation, the RIP1/RIP3 necrosome complex II is formed. These complexes induce necrosis through the caspase-3-independent pathway mediated by calpain, cathepsin B/D, and apoptosis-inducing factor (AIF). AIF has a dual role in apoptosis and necrosis. At high doses, AIF promotes chromatinolysis and necrosis by interacting with histone H2AX. In addition, NF-κB, STAT-3, and HIF-1 play a crucial role in radiation-induced inflammatory responses embedded in a complex inflammatory network. Analysis of inflammatory markers in matched plasma and cerebrospinal fluid (CSF) isolated from in vivo specimens demonstrated the upregulation of chemokines and cytokines during the necrosis phase. Using RIP1/RIP3 kinase specific inhibitors (Nec-1, GSK'872), we also establish that the RIP1-RIP3 complex regulates programmed necrosis after either high-dose radiation or TNF-α-induced necrosis requires RIP1 and RIP3 kinases. Overall, our data shed new light on the relationship between RIP1/RIP3-mediated programmed necrosis and AIF-mediated caspase-independent programmed necrosis in glioblastoma. PMID:26684801

  15. Cooling systems and hybrid A/C systems using an electromagnetic radiation-absorbing complex

    SciTech Connect

    Halas, Nancy J.; Nordlander, Peter; Neumann, Oara

    2015-05-19

    A method for powering a cooling unit. The method including applying electromagnetic (EM) radiation to a complex, where the complex absorbs the EM radiation to generate heat, transforming, using the heat generated by the complex, a fluid to vapor, and sending the vapor from the vessel to a turbine coupled to a generator by a shaft, where the vapor causes the turbine to rotate, which turns the shaft and causes the generator to generate the electric power, wherein the electric powers supplements the power needed to power the cooling unit

  16. Compliance of Bhabhatron-II telecobalt unit with IEC standard - Radiation safety.

    PubMed

    Sahani, G; Kumar, Munish; Dash Sharma, P K; Sharma, D N; Chhokra, Kanta; Mishra, Bibekananda; Agarwal, S P; Kher, R K

    2009-01-01

    Bhabha Atomic Research Centre, Mumbai, India designed and developed a telecobalt unit, which was named as Bhabhatron-II. In this paper, the results pertaining to radiation safety of indigenously developed Bhabhatron-II telecobalt unit are reported. The various tests were carried out as per requirements of International Electrotechnical Commission standard and acceptance criteria developed nationally. Various devices such as CaSO4:Dy based thermoluminescent dosimeters, farmer type ionization chamber, water phantom and radiographic films were used. All the parameters pertaining to radiation leakage/transmission were within the tolerance limits as per IEC-60601-2-11 standard except the collimator transmission through X collimators (upper jaw), which marginally exceeds the tolerance limit. PMID:19458599

  17. Design of organic scintillators for non-standard radiation field dosimetry: experimental setup.

    PubMed

    Norman H, Machado R; Maximiliano, Trujillo T; Javier E, García G; Diana C, Narvaez G; Paula A, Marín M; Róbinson A, Torres V

    2013-01-01

    This paper describes an experimental setup designed for sensing the luminescent light coming from an organic plastic scintillator stimulated with ionizing radiation. This device is intended to be a part of a complete dosimeter system for characterization of small radiation fields which is the project of the doctoral thesis of the medical physicist at the Radiation Oncology facility of Hospital San Vicente Fundación in conjunction with the Universidad de Antioquia of Medellín Colombia. Some preliminary results predict a good performance of the unit, but further studies must be conducted in order to have a completed evaluation of the system. This is the first step in the development of an accuracy tool for measurement of non-standard fields in the Radiotherapy or Radiosurgery processes. PMID:24110369

  18. Combined micro-and standard percutaneous nephrolithotomy for complex renal calculi

    PubMed Central

    Buldu, İbrahim; Tepeler, Abdulkadir; Karatağ, Tuna; İnan, Ramazan; Armağan, Abdullah; İstanbulluoğlu, Okan

    2016-01-01

    Objective We aimed to present the technique of combination of standard percutaneous nephrolithotomy (PNL) with microperc for achieving higher success rates without increasing complication rates in the management of complex renal calculi. Material and methods The patients who underwent microperc procedure as a complementary procedure to standard PNL for complex kidney stones in two reference hospitals between 2013 and 2015, were evaluated retrospectively. Results All patients underwent a total of two accesses one for standard PNL and one for microperc. The mean stone size was measured as 54.3 mm. The procedures were completed after an average operative time of 88.2 minutes and fluoroscopy time of 5.3 minutes. Stone free status was achieved in 18 cases (78.2%) and small residual fragments (≤4 mm) were detected in 3 cases (13.1%). Complications were seen in three patients (13%) as hemorrhage in one and postoperative fever in two patients. Conclusion Despite the limitations of this study, the combination of standard PNL and microperc might reduce the complication rates and increase the success rates when treating complex kidney stones. Future prospective and comparative studies are needed.

  19. Calibration of the Standards and Calibration Laboratory`s Co{sup 60} Radiation Pool

    SciTech Connect

    Wirtenson, G.R.; White, R.H.

    1993-01-01

    The authors report measurements of dose rates at various locations in the LLNL Standards and Calibrations Laboratory`s Co{sup 60} Radiation Pool. Plots show the dependence of dose rate on radius near the bottom of the pool and the dependence of dose rate on height at a fixed distance from the pool center. The effect of varying sample location within the pool`s dry-well was also investigated.

  20. Non-Standard Neutrino Physics Probed by Tokai-To Two-Detector Complex

    NASA Astrophysics Data System (ADS)

    Ribeiro, Nei Cipriano; Kajita, Takaaki; Ko, Pyungwon; Minakata, Hisakazu; Nakayama, Shoei; Nunokawa, Hiroshi

    2009-01-01

    The discovery potentials of non-standard physics (NSP) which might be possessed by neutrinos are examined by taking a concrete setting of Tokai-to-Kamioka-Korea (T2KK) two detector complex which receives neutrino superbeam from J-PARC. We restrict ourselves into νμ and {bar v}μ disappearance measurement. We describe here only the non-standard interactions (NSI) of neutrinos with matter and the quantum decoherence. It is shown in some favorable cases T2KK can significantly improve the current bounds on NSP. For NSI, for example, ɛμτ < 0.03, which is a factor 5 severer than the current one.

  1. Modern Palliative Radiation Treatment: Do Complexity and Workload Contribute to Medical Errors?

    SciTech Connect

    D'Souza, Neil; Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario ; Holden, Lori; Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario ; Robson, Sheila; Mah, Kathy; Di Prospero, Lisa; Wong, C. Shun; Chow, Edward; Spayne, Jacqueline; Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario

    2012-09-01

    Purpose: To examine whether treatment workload and complexity associated with palliative radiation therapy contribute to medical errors. Methods and Materials: In the setting of a large academic health sciences center, patient scheduling and record and verification systems were used to identify patients starting radiation therapy. All records of radiation treatment courses delivered during a 3-month period were retrieved and divided into radical and palliative intent. 'Same day consultation, planning and treatment' was used as a proxy for workload and 'previous treatment' and 'multiple sites' as surrogates for complexity. In addition, all planning and treatment discrepancies (errors and 'near-misses') recorded during the same time frame were reviewed and analyzed. Results: There were 365 new patients treated with 485 courses of palliative radiation therapy. Of those patients, 128 (35%) were same-day consultation, simulation, and treatment patients; 166 (45%) patients had previous treatment; and 94 (26%) patients had treatment to multiple sites. Four near-misses and 4 errors occurred during the audit period, giving an error per course rate of 0.82%. In comparison, there were 10 near-misses and 5 errors associated with 1100 courses of radical treatment during the audit period. This translated into an error rate of 0.45% per course. An association was found between workload and complexity and increased palliative therapy error rates. Conclusions: Increased complexity and workload may have an impact on palliative radiation treatment discrepancies. This information may help guide the necessary recommendations for process improvement for patients who require palliative radiation therapy.

  2. Influence of inhomogeneous damping distribution on sound radiation properties of complex vibration modes in rectangular plates

    NASA Astrophysics Data System (ADS)

    Unruh, Oliver

    2016-09-01

    In order to reduce noise emitted by vibrating structures additional damping treatments such as constraint layer damping or embedded elastomer layers can be used. To save weight and cost, the additional damping is often placed at some critical locations of the structure, what leads to spatially inhomogeneous distribution of damping. This inhomogeneous distribution of structural damping leads to an occurrence of complex vibration modes, which are no longer dominated by pure standing waves, but by a superposition of travelling and standing waves. The existence of complex vibration modes raises the question about their influence on sound radiation. Previous studies on the sound radiation of complex modes of rectangular plates reveal, that, depending on the direction of travelling waves, the radiation efficiency of structural modes can slightly decrease or significantly increase. These observations have been made using a rectangular plate with a simple inhomogeneous damping configuration which includes a single plate boundary with a higher structural damping ratio. In order to answer the question about the influence of other possible damping configurations on the sound radiation properties, this paper addresses the self- and mutual-radiation efficiencies of the resulting complex vibration modes. Numerical simulations are used for the calculation of complex structural modes of different inhomogeneous damping configurations with varying geometrical form and symmetry. The evaluation of self- and mutual-radiation efficiencies reveals that primarily the symmetry properties of the inhomogeneous damping distribution affect the sound radiation characteristics. Especially the asymmetric distributions of inhomogeneous damping show a high influence on the investigated acoustic metrics. The presented study also reveals that the acoustic cross-coupling between structural modes, which is described by the mutual-radiation efficiencies, generally increases with the presence of

  3. Study of decoder complexity for HEVC and AVC standards based on tool-by-tool comparison

    NASA Astrophysics Data System (ADS)

    Ahn, Y. J.; Han, W. J.; Sim, D. G.

    2012-10-01

    High Efficiency Video Coding (HEVC) is the latest standardization efforts of ISO/IEC MPEG and ITU-T VCEG for further improving the coding efficiency of H.264/AVC standard. It has been reported that HEVC can provide comparable subjective visual quality with H.264/AVC at only half bit-rates in many cases. In this paper, decoder complexities between HEVC and H.264/AVC are studied for providing initial complexity estimates of the HEVC decoder compared with the H.264/AVC decoder. For this purpose, several selected coding tools including intra prediction, motion compensation, transform, loop filters and entropy coder have been analyzed in terms of number of operations as well as their statistical differences.

  4. Prophylactic UV Radiation and CIE Standard on Photobiological Safety of Lamps and Lamp Systems

    NASA Astrophysics Data System (ADS)

    Sarychev, Genrih; Gavrilkina, Galina

    Two aspects of UV photobiology have come up almost simultaneously for discussion. On the one hand, the CIE has, for all practical purposes, completed discussions of a new standard “CIE S 009/E: 2002 Photobiological Safety of Lamps and Lamp Systems”1), and it was adopted without any amendments. On the other hand, some national standards (for example, in Russia) have for decades insisted on UVA+UVB radiation being used for prophylactic purposes at actinic erythemal doses (around 140 J m-2 per 8 hours of irradiation), which are significantly higher than prohibitive doses of actinic UV hazard (30 J m-2) suggested in the CIE standard. It seems that this arisen situation is to be thought about more carefully.

  5. The standard enthalpies of combustion and formation of crystalline cobalt tetrakis(4-metoxyphenyl)porphin complex

    NASA Astrophysics Data System (ADS)

    Tarasov, R. P.; Volkov, A. V.; Bazanov, M. I.; Semeikin, A. S.

    2009-05-01

    The energy of combustion of cobalt tetrakis(4-metoxyphenyl)porphin was determined in an isothermic-shell liquid calorimeter with a stationary calorimetric bomb. The standard enthalpies of combustion and formation of the complex were calculated, -Δ c H o = 27334.06 ± 50.98 kJ/mol and Δf H o = 3062.90 ± 50.97 kJ/mol.

  6. ANSI and IEC standards for, and evaluation of, radiation detection instrumentation

    SciTech Connect

    Chiaro Jr, Peter John

    2008-01-01

    During the last quarter of 2002, an effort was started to develop performance requirements for radiation instrumentation used for the detection of illicit trafficking of radioactive material. Coordinated by the US National Institute of Science and Technology (NIST), a team was formed to establish writing committees for the development of these requirements as American National Standards Institute (ANSI) standards. The core of the new area was developed as ANSI N42, Homeland Security Instruments. A series of standards were developed followed by testing and evaluation (T&E) protocols that would be used for specific testing. Four US National Laboratories provided T&E support and work commenced to test instruments provided by manufacturers at no cost. During this time, discussions began regarding the formation of a new work group within the International Electrotechnical Commission (IEC). This new work group would be located within technical committee (TC) 45 which addresses nuclear instrumentation. This new work group, 15B, also began developing international standards to address the same instrument types. Following development of ANSI standards, the testing and evaluation process began, running for two distinct rounds. The results of the work was consolidated by NIST and released back to individual companies as well as the user community in a controlled manner. This document will provide details regarding the standards and their basis and status, as well as some information regarding the T&E process used in the USA.

  7. Analysis of thermal radiation in ion traps for optical frequency standards

    NASA Astrophysics Data System (ADS)

    Doležal, M.; Balling, P.; Nisbet-Jones, P. B. R.; King, S. A.; Jones, J. M.; Klein, H. A.; Gill, P.; Lindvall, T.; Wallin, A. E.; Merimaa, M.; Tamm, C.; Sanner, C.; Huntemann, N.; Scharnhorst, N.; Leroux, I. D.; Schmidt, P. O.; Burgermeister, T.; Mehlstäubler, T. E.; Peik, E.

    2015-12-01

    In many of the high-precision optical frequency standards with trapped atoms or ions that are under development to date, the ac Stark shift induced by thermal radiation leads to a major contribution to the systematic uncertainty. We present an analysis of the inhomogeneous thermal environment experienced by ions in various types of ion traps. Finite element models which allow the determination of the temperature of the trap structure and the temperature of the radiation were developed for five ion trap designs, including operational traps at PTB and NPL and further optimized designs. Models were refined based on comparison with infrared camera measurement until an agreement of better than 10% of the measured temperature rise at critical test points was reached. The effective temperature rises of the radiation seen by the ion range from 0.8 K to 2.1 K at standard working conditions. The corresponding fractional frequency shift uncertainties resulting from the uncertainty in temperature are in the 10-18 range for optical clocks based on the Sr+ and Yb+ E2 transitions, and even lower for Yb+ E3, In+ and Al+. Issues critical for heating of the trap structure and its predictability were identified and design recommendations developed.

  8. MO-G-9A-01: Imaging Refresher for Standard of Care Radiation Therapy

    SciTech Connect

    Labby, Z; Sensakovic, W; Hipp, E; Altman, M

    2014-06-15

    Imaging techniques and technology which were previously the domain of diagnostic medicine are becoming increasingly integrated and utilized in radiation therapy (RT) clinical practice. As such, there are a number of specific imaging topics that are highly applicable to modern radiation therapy physics. As imaging becomes more widely integrated into standard clinical radiation oncology practice, the impetus is on RT physicists to be informed and up-to-date on those imaging modalities relevant to the design and delivery of therapeutic radiation treatments. For example, knowing that, for a given situation, a fluid attenuated inversion recovery (FLAIR) image set is most likely what the physician would like to import and contour is helpful, but may not be sufficient to providing the best quality of care. Understanding the physics of how that pulse sequence works and why it is used could help assess its utility and determine if it is the optimal sequence for aiding in that specific clinical situation. It is thus important that clinical medical physicists be able to understand and explain the physics behind the imaging techniques used in all aspects of clinical radiation oncology practice. This session will provide the basic physics for a variety of imaging modalities for applications that are highly relevant to radiation oncology practice: computed tomography (CT) (including kV, MV, cone beam CT [CBCT], and 4DCT), positron emission tomography (PET)/CT, magnetic resonance imaging (MRI), and imaging specific to brachytherapy (including ultrasound and some brachytherapy specific topics in MR). For each unique modality, the image formation process will be reviewed, trade-offs between image quality and other factors (e.g. imaging time or radiation dose) will be clarified, and typically used cases for each modality will be introduced. The current and near-future uses of these modalities and techniques in radiation oncology clinical practice will also be discussed. Learning

  9. Radiated radiofrequency immunity testing of automated external defibrillators - modifications of applicable standards are needed

    PubMed Central

    2011-01-01

    Background We studied the worst-case radiated radiofrequency (RF) susceptibility of automated external defibrillators (AEDs) based on the electromagnetic compatibility (EMC) requirements of a current standard for cardiac defibrillators, IEC 60601-2-4. Square wave modulation was used to mimic cardiac physiological frequencies of 1 - 3 Hz. Deviations from the IEC standard were a lower frequency limit of 30 MHz to explore frequencies where the patient-connected leads could resonate. Also testing up to 20 V/m was performed. We tested AEDs with ventricular fibrillation (V-Fib) and normal sinus rhythm signals on the patient leads to enable testing for false negatives (inappropriate "no shock advised" by the AED). Methods We performed radiated exposures in a 10 meter anechoic chamber using two broadband antennas to generate E fields in the 30 - 2500 MHz frequency range at 1% frequency steps. An AED patient simulator was housed in a shielded box and delivered normal and fibrillation waveforms to the AED's patient leads. We developed a technique to screen ECG waveforms stored in each AED for electromagnetic interference at all frequencies without waiting for the long cycle times between analyses (normally 20 to over 200 s). Results Five of the seven AEDs tested were susceptible to RF interference, primarily at frequencies below 80 MHz. Some induced errors could cause AEDs to malfunction and effectively inhibit operator prompts to deliver a shock to a patient experiencing lethal fibrillation. Failures occurred in some AEDs exposed to E fields between 3 V/m and 20 V/m, in the 38 - 50 MHz range. These occurred when the patient simulator was delivering a V-Fib waveform to the AED. Also, we found it is not possible to test modern battery-only-operated AEDs for EMI using a patient simulator if the IEC 60601-2-4 defibrillator standard's simulated patient load is used. Conclusions AEDs experienced potentially life-threatening false-negative failures from radiated RF, primarily

  10. A new absolute method for the standardization of radionuclides emitting low-energy radiation.

    PubMed

    Leblanc, E; de, Marcillac P; Coron, N; Leblanc, J; Loidl, M; Metge, J F; Bouchard, J

    2002-01-01

    Microcalorimeters (or bolometers) operated at temperatures below 100 mK allow individual counting of photons and electrons with a very low energy detection threshold. The physics is based on the pulse temperature increase of the target (or absorber) of the detector due to the complete absorption of both electrons and photons. Since this target can be constructed with a perfect 4-pi geometry, a bolometer offers potentially a new method for absolute activity measurements of radionuclides emitting low-energy radiation. In this paper we present our first results of a feasibility study of activity standardization of a 55Fe solution with a prototype 4-pi bolometer. PMID:11839023

  11. National Institute of Standards and Technology Synchrotron Radiation Facilities for Materials Science

    PubMed Central

    Long, Gabrielle G.; Allen, Andrew J.; Black, David R.; Burdette, Harold E.; Fischer, Daniel A.; Spal, Richard D.; Woicik, Joseph C.

    2001-01-01

    Synchrotron Radiation Facilities, supported by the Materials Science and Engineering Laboratory of the National Institute of Standards and Technology, include beam stations at the National Synchrotron Light Source at Brookhaven National Laboratory and at the Advanced Photon Source at Argonne National Laboratory. The emphasis is on materials characterization at the microstructural and at the atomic and molecular levels, where NIST scientists, and researchers from industry, universities and government laboratories perform state-of-the-art x-ray measurements on a broad range of materials.

  12. Beyond the Standard Curriculum: A Review of Available Opportunities for Medical Students to Prepare for a Career in Radiation Oncology

    SciTech Connect

    Agarwal, Ankit; DeNunzio, Nicholas J.; Ahuja, Divya; Hirsch, Ariel E.

    2014-01-01

    Purpose: To review currently available opportunities for medical students to supplement their standard medical education to prepare for a career in radiation oncology. Methods and Materials: Google and PubMed were used to identify existing clinical, health policy, and research programs for medical students in radiation oncology. In addition, results publicly available by the National Resident Matching Program were used to explore opportunities that successful radiation oncology applicants pursued during their medical education, including obtaining additional graduate degrees. Results: Medical students can pursue a wide variety of opportunities before entering radiation oncology. Several national specialty societies, such as the American Society for Radiation Oncology and the Radiological Society of North America, offer summer internships for medical students interested in radiation oncology. In 2011, 30% of allopathic senior medical students in the United States who matched into radiation oncology had an additional graduate degree, including PhD, MPH, MBA, and MA degrees. Some medical schools are beginning to further integrate dedicated education in radiation oncology into the standard 4-year medical curriculum. Conclusions: To the authors' knowledge, this is the first comprehensive review of available opportunities for medical students interested in radiation oncology. Early exposure to radiation oncology and additional educational training beyond the standard medical curriculum have the potential to create more successful radiation oncology applicants and practicing radiation oncologists while also promoting the growth of the field. We hope this review can serve as guide to radiation oncology applicants and mentors as well as encourage discussion regarding initiatives in radiation oncology opportunities for medical students.

  13. Hypofractionated Versus Standard Radiation Therapy With or Without Temozolomide for Older Glioblastoma Patients

    SciTech Connect

    Arvold, Nils D.; Aizer, Ayal A.; Chiocca, E. Antonio

    2015-06-01

    Purpose: Older patients with newly diagnosed glioblastoma have poor outcomes, and optimal treatment is controversial. Hypofractionated radiation therapy (HRT) is frequently used but has not been compared to patients receiving standard fractionated radiation therapy (SRT) and temozolomide (TMZ). Methods and Materials: We conducted a retrospective analysis of patients ≥65 years of age who received radiation for the treatment of newly diagnosed glioblastoma from 1994 to 2013. The distribution of clinical covariates across various radiation regimens was analyzed for possible selection bias. Survival was calculated using the Kaplan-Meier method. Comparison of hypofractionated radiation (typically, 40 Gy/15 fractions) versus standard fractionation (typically, 60 Gy/30 fractions) in the setting of temozolomide was conducted using Cox regression and propensity score analysis. Results: Patients received SRT + TMZ (n=57), SRT (n=35), HRT + TMZ (n=34), or HRT (n=9). Patients receiving HRT were significantly older (median: 79 vs 69 years of age; P<.001) and had worse baseline performance status (P<.001) than those receiving SRT. On multivariate analysis, older age (adjusted hazard ratio [AHR]: 1.06; 95% confidence interval [CI]: 1.01-1.10, P=.01), lower Karnofsky performance status (AHR: 1.02; 95% CI: 1.01-1.03; P=.01), multifocal disease (AHR: 2.11; 95% CI: 1.23-3.61, P=.007), and radiation alone (vs SRT + TMZ; SRT: AHR: 1.72; 95% CI: 1.06-2.79; P=.03; HRT: AHR: 3.92; 95% CI: 1.44-10.60, P=.007) were associated with decreased overall survival. After propensity score adjustment, patients receiving HRT with TMZ had similar overall survival compared with those receiving SRT with TMZ (AHR: 1.10, 95% CI: 0.50-2.4, P=.82). Conclusions: With no randomized data demonstrating equivalence between HRT and SRT in the setting of TMZ for glioblastoma, significant selection bias exists in the implementation of HRT. Controlling for this bias, we observed similar overall

  14. Kolmogorov Complexity Spectrum for Use in Analysis of Uv-B Radiation Time Series

    NASA Astrophysics Data System (ADS)

    Mihailović, Dragutin T.; Malinović-Milićević, Slavica; Arsenić, Ilija; Drešković, Nusret; Bukosa, Beata

    2013-10-01

    In this paper, we have used the Kolmogorov complexity and sample entropy measures to estimate the complexity of the UV-B radiation time series in the Vojvodina region (Serbia) for the period 1990-2007. We have defined the Kolmogorov complexity spectrum and have introduced the Kolmogorov complexity spectrum highest value (KCH). We have established the UV-B radiation time series on the basis of their daily sum (dose) for seven representative places in this region using: (i) measured data, (ii) data calculated via a derived empirical formula and (iii) data obtained by a parametric UV radiation model. We have calculated the Kolmogorov complexity (KC) based on the Lempel-Ziv algorithm (LZA), KCH and sample entropy (SE) values for each time series. We have divided the period 1990-2007 into two subintervals: (i) 1990-1998 and (ii) 1999-2007 and calculated the KC, KCH and SE values for the various time series in these subintervals. It is found that during the period 1999-2007, there is a decrease in the KC, KCH and SE, compared to the period 1990-1998. This complexity loss may be attributed to (i) the increased human intervention in the post civil war period causing increase of the air pollution and (ii) the increased cloudiness due to climate changes.

  15. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  16. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  17. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  18. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  19. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., App. F Appendix F to Part 75—Standards for Licensing Radiographers, Nuclear Medicine Technologists... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2....

  20. Scaling and parametrization of clear-sky solar radiation over complex topography

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solar radiation at the land surface is influenced by slope, aspect, shadows and obstruction of the sky, all of which vary over a wide range of length scales in regions of complex topography, with important consequences for the surface energy balance. Atmospheric models, however, generally assume the...

  1. Scaling and parameterization of clear-sky solar radiation over complex topography

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solar radiation at the land surface is influenced by slope, aspect, shadows, and obstruction of the sky, all of which vary over a wide range of length scales in regions of complex topography, with important consequences for the surface energy balance. Atmospheric models, however, generally assume t...

  2. A general method for computing the total solar radiation force on complex spacecraft structures

    NASA Technical Reports Server (NTRS)

    Chan, F. K.

    1981-01-01

    The method circumvents many of the existing difficulties in computational logic presently encountered in the direct analytical or numerical evaluation of the appropriate surface integral. It may be applied to complex spacecraft structures for computing the total force arising from either specular or diffuse reflection or even from non-Lambertian reflection and re-radiation.

  3. Interlaboratory reproducibility of large-scale human protein-complex analysis by standardized AP-MS.

    PubMed

    Varjosalo, Markku; Sacco, Roberto; Stukalov, Alexey; van Drogen, Audrey; Planyavsky, Melanie; Hauri, Simon; Aebersold, Ruedi; Bennett, Keiryn L; Colinge, Jacques; Gstaiger, Matthias; Superti-Furga, Giulio

    2013-04-01

    The characterization of all protein complexes of human cells under defined physiological conditions using affinity purification-mass spectrometry (AP-MS) is a highly desirable step in the quest to understand the phenotypic effects of genomic information. However, such a challenging goal has not yet been achieved, as it requires reproducibility of the experimental workflow and high data consistency across different studies and laboratories. We systematically investigated the reproducibility of a standardized AP-MS workflow by performing a rigorous interlaboratory comparative analysis of the interactomes of 32 human kinases. We show that it is possible to achieve high interlaboratory reproducibility of this standardized workflow despite differences in mass spectrometry configurations and subtle sample preparation-related variations and that combination of independent data sets improves the approach sensitivity, resulting in even more-detailed networks. Our analysis demonstrates the feasibility of obtaining a high-quality map of the human protein interactome with a multilaboratory project. PMID:23455922

  4. Quantification of beam complexity in intensity-modulated radiation therapy treatment plans

    SciTech Connect

    Du, Weiliang Cho, Sang Hyun; Zhang, Xiaodong; Kudchadker, Rajat J.; Hoffman, Karen E.

    2014-02-15

    Purpose: Excessive complexity in intensity-modulated radiation therapy (IMRT) plans increases the dose uncertainty, prolongs the treatment time, and increases the susceptibility to changes in patient or target geometry. To date, the tools for quantitative assessment of IMRT beam complexity are still lacking. In this study, The authors have sought to develop metrics to characterize different aspects of beam complexity and investigate the beam complexity for IMRT plans of different disease sites. Methods: The authors evaluated the beam complexity scores for 65 step-and-shoot IMRT plans from three sites (prostate, head and neck, and spine) and 26 volumetric-modulated arc therapy (VMAT) plans for the prostate. On the basis of the beam apertures and monitor unit weights of all segments, the authors calculated the mean aperture area, extent of aperture shape irregularity, and degree of beam modulation for each beam. Then the beam complexity values were averaged to obtain the complexity metrics of the IMRT plans. The authors studied the correlation between the beam complexity metrics and the quality assurance (QA) results. Finally, the effects of treatment planning parameters on beam complexity were studied. Results: The beam complexity scores were not uniform among the prostate IMRT beams from different gantry angles. The lateral beams had larger monitor units and smaller shape irregularity, while the anterior-posterior beams had larger modulation values. On average, the prostate IMRT plans had the smallest aperture irregularity, beam modulation, and normalized monitor units; the head and neck IMRT plans had large beam irregularity and beam modulation; and the spine stereotactic radiation therapy plans often had small beam apertures, which may have been associated with the relatively large discrepancies between planned and QA measured doses. There were weak correlations between the beam complexity scores and the measured dose errors. The prostate VMAT beams showed

  5. Organisational standards for the delivery of intensity-modulated radiation therapy in Ontario.

    PubMed

    Whitton, A; Warde, P; Sharpe, M; Oliver, T K; Bak, K; Leszczynski, K; Etheridge, S; Fleming, K; Gutierrez, E; Favell, L; Green, E

    2009-04-01

    By minimising the effect of irradiation on surrounding tissue, intensity-modulated radiation therapy (IMRT) can deliver higher, more effective doses to the targeted tumour site, minimising treatment-related morbidity and possibly improving cancer control and cure. A multidisciplinary IMRT Expert Panel was convened to develop the organisational standards for the delivery of IMRT. The systematic literature search used MEDLINE, EMBASE, the Cochrane Database, the National Guidelines Clearing House and the Health Technology Assessment Database. An environmental scan of unpublished literature used the Google search engine to review the websites of key organisations, cancer agencies/centres and vendor sites in Canada, the USA, Australia and Europe. In total, 22 relevant guidance documents were identified; 12 from the published literature and 10 from the environmental scan. Professional and organisational standards for the provision of IMRT were developed through the analysis of this evidence and the consensus opinion of the IMRT Expert Panel. The resulting standards address the following domains: planning of new IMRT programmes, practice setting requirements, tools, devices and equipment requirements; professional training requirements; role of personnel; and requirements for quality assurance and safety. Here the IMRT Expert Panel offers organisational and professional standards for the delivery of IMRT, with the intent of promoting innovation, improving access and enhancing patient care. PMID:19062263

  6. Toxic variability and radiation sensitization by dichlorodiammineplatinum(II) complexes in Salmonella typhimurium cells

    SciTech Connect

    Richmond, R.C.

    1984-09-01

    The oxidative coordination compound cis-dichlorodiammineplatinum(II) (cis-DDP) is again shown to be a hypoxic cell radiation sensitizer. The mechanism of cis-DDP-induced radiation sensitization is complex. Results here indicate that cis-DDP sensitization operates in part through reactive free radicals, in part through the interactions of radiation-induced reactive Pt(I) intermediates, and in part through the involvement of thermodynamic and kinetic aspects of Pt(II)-DNA binding during irradiation. For the first time, radiation sensitization by trans-DDP is compared with a sensitizing concentration of cis-DDP within the same study. Both analogs are sensitizers, but with significant differences. Further, irradiated hypoxic solutions of cis-DDP are found to be more toxic than unirradiated solutions.

  7. Technical Note: Modeling a complex micro-multileaf collimator using the standard BEAMnrc distribution

    SciTech Connect

    Kairn, T.; Kenny, J.; Crowe, S. B.; Fielding, A. L.; Franich, R. D.; Johnston, P. N.; Knight, R. T.; Langton, C. M.; Schlect, D.; Trapp, J. V.

    2010-04-15

    Purpose: The component modules in the standard BEAMnrc distribution may appear to be insufficient to model micro-multileaf collimators that have trifaceted leaf ends and complex leaf profiles. This note indicates, however, that accurate Monte Carlo simulations of radiotherapy beams defined by a complex collimation device can be completed using BEAMnrc's standard VARMLC component module. Methods: That this simple collimator model can produce spatially and dosimetrically accurate microcollimated fields is illustrated using comparisons with ion chamber and film measurements of the dose deposited by square and irregular fields incident on planar, homogeneous water phantoms. Results: Monte Carlo dose calculations for on-axis and off-axis fields are shown to produce good agreement with experimental values, even on close examination of the penumbrae. Conclusions: The use of a VARMLC model of the micro-multileaf collimator, along with a commissioned model of the associated linear accelerator, is therefore recommended as an alternative to the development or use of in-house or third-party component modules for simulating stereotactic radiotherapy and radiosurgery treatments. Simulation parameters for the VARMLC model are provided which should allow other researchers to adapt and use this model to study clinical stereotactic radiotherapy treatments.

  8. Quasi-analytical treatment of spatially averaged radiation transfer in complex terrain

    NASA Astrophysics Data System (ADS)

    LöWe, H.; Helbig, N.

    2012-10-01

    We provide a new quasi-analytical method to compute the subgrid topographic influences on the shortwave radiation fluxes and the effective albedo in complex terrain as required for large-scale meteorological, land surface, or climate models. We investigate radiative transfer in complex terrain via the radiosity equation on isotropic Gaussian random fields. Under controlled approximations we derive expressions for domain-averaged fluxes of direct, diffuse, and terrain radiation and the sky view factor. Domain-averaged quantities can be related to a type of level-crossing probability of the random field, which is approximated by long-standing results developed for acoustic scattering at ocean boundaries. This allows us to express all nonlocal horizon effects in terms of a local terrain parameter, namely, the mean-square slope. Emerging integrals are computed numerically, and fit formulas are given for practical purposes. As an implication of our approach, we provide an expression for the effective albedo of complex terrain in terms of the Sun elevation angle, mean-square slope, the area-averaged surface albedo, and the ratio of atmospheric direct beam to diffuse radiation. For demonstration we compute the decrease of the effective albedo relative to the area-averaged albedo in Switzerland for idealized snow-covered and clear-sky conditions at noon in winter. We find an average decrease of 5.8% and spatial patterns which originate from characteristics of the underlying relief. Limitations and possible generalizations of the method are discussed.

  9. Influence of complex impurity centres on radiation damage in wide-gap metal oxides

    NASA Astrophysics Data System (ADS)

    Lushchik, A.; Lushchik, Ch.; Popov, A. I.; Schwartz, K.; Shablonin, E.; Vasil'chenko, E.

    2016-05-01

    Different mechanisms of radiation damage of wide-gap metal oxides as well as a dual influence of impurity ions on the efficiency of radiation damage have been considered on the example of binary ionic MgO and complex ionic-covalent Lu3Al5O12 single crystals. Particular emphasis has been placed on irradiation with ∼2 GeV heavy ions (197Au, 209Bi, 238U, fluence of 1012 ions/cm2) providing extremely high density of electronic excitations within ion tracks. Besides knock-out mechanism for Frenkel pair formation, the additional mechanism through the collapse of mobile discrete breathers at certain lattice places (e.g., complex impurity centres) leads to the creation of complex defects that involve a large number of host atoms. The experimental manifestations of the radiation creation of intrinsic and impurity antisite defects (Lu|Al or Ce|Al - a heavy ion in a wrong cation site) have been detected in LuAG and LuAG:Ce3+ single crystals. Light doping of LuAG causes a small enhancement of radiation resistance, while pair impurity centres (for instance, Ce|Lu-Ce|Al or Cr3+-Cr3+ in MgO) are formed with a rise of impurity concentration. These complex impurity centres as well as radiation-induced intrinsic antisite defects (Lu|Al strongly interacting with Lu in a regular site) tentatively serve as the places for breathers collapse, thus decreasing the material resistance against dense irradiation.

  10. Performance demonstration of 4πβ(LS)-γ coincidence counting system for standardization of radionuclides with complex decay scheme.

    PubMed

    Kulkarni, D B; Anuradha, R; Joseph, Leena; Kulkarni, M S; Tomar, B S

    2016-02-01

    A standardization of (134)Cs and (131)I was carried out in order to demonstrate the performance and applicability of the 4πβ(LS)-γ coincidence counting system for standardization of radionuclides with complex decay scheme. The coincidence analyzer, capable of analyzing coincidence between beta and two gamma windows simultaneously, was developed and used for the standardization. The use of this dual coincidence analyzer has reduced the total experimental time by half. The activity concentrations obtained using the 4πβ(LS)-γ coincidence counting system, a 4πβ(PC)-γ coincidence counting system, and the CIEMAT/NIST method are in excellent agreement with each other within uncertainty limits and hence demonstrates its performance for standardization of radionuclides decaying with complex decay scheme. Hence use of this 4πβ(LS)-γ coincidence counting system can be an alternative method suitable to standardize radionuclides with complex decay scheme with acceptable precision. PMID:26678524

  11. Blackbody-radiation shift in a {sup 43}Ca{sup +} ion optical frequency standard

    SciTech Connect

    Arora, Bindiya; Safronova, M. S.; Clark, Charles W.

    2007-12-15

    Motivated by the prospect of an optical frequency standard based on {sup 43}Ca{sup +}, we calculate the blackbody-radiation (BBR) shift of the 4s{sub 1/2}-3d{sub 5/2} clock transition, which is a major component of the uncertainty budget. The calculations are based on the relativistic all-order single-double method where all single and double excitations of the Dirac-Fock wave function are included to all orders of perturbation theory. Additional calculations are conducted for the dominant contributions in order to evaluate some omitted high-order corrections and estimate the uncertainties of the final results. The BBR shift obtained for this transition is 0.38(1) Hz. The tensor polarizability of the 3d{sub 5/2} level is also calculated and its uncertainty is evaluated as well. Our results are compared with other calculations.

  12. Assessing Interpersonal and Communication Skills in Radiation Oncology Residents: A Pilot Standardized Patient Program

    SciTech Connect

    Ju, Melody; Berman, Abigail T.; Hwang, Wei-Ting; LaMarra, Denise; Baffic, Cordelia; Suneja, Gita; Vapiwala, Neha

    2014-04-01

    Purpose: There is a lack of data for the structured development and evaluation of communication skills in radiation oncology residency training programs. Effective communication skills are increasingly emphasized by the Accreditation Council for Graduate Medical Education and are critical for a successful clinical practice. We present the design of a novel, pilot standardized patient (SP) program and the evaluation of communication skills among radiation oncology residents. Methods and Materials: Two case scenarios were developed to challenge residents in the delivery of “bad news” to patients: one scenario regarding treatment failure and the other regarding change in treatment plan. Eleven radiation oncology residents paired with 6 faculty participated in this pilot program. Each encounter was scored by the SPs, observing faculty, and residents themselves based on the Kalamazoo guidelines. Results: Overall resident performance ratings were “good” to “excellent,” with faculty assigning statistically significant higher scores and residents assigning lower scores. We found inconsistent inter rater agreement among faculty, residents, and SPs. SP feedback was also valuable in identifying areas of improvement, including more collaborative decision making and less use of medical jargon. Conclusions: The program was well received by residents and faculty and regarded as a valuable educational experience that could be used as an annual feedback tool. Poor inter rater agreement suggests a need for residents and faculty physicians to better calibrate their evaluations to true patient perceptions. High scores from faculty members substantiate the concern that resident evaluations are generally positive and nondiscriminating. Faculty should be encouraged to provide honest and critical feedback to hone residents' interpersonal skills.

  13. Linear No-Threshold model and standards for protection against radiation.

    PubMed

    Shamoun, Dima Yazji

    2016-06-01

    In response to the three petitions by Carol S. Marcus, Mark L. Miller, and Mohan Doss, dated February 9, February 13, and February 24, 2015, respectively, the Nuclear Regulatory Commission (NRC or the Commission) has announced that it is considering assessing its choice of dose-response model, the Linear No-Threshold (LNT) model, for exposure to ionizing radiation. This comment is designed to assist the Commission in evaluating the merits of a review of the default dose-response model it uses as the basis for the Standards for Protection against Radiation regulations. It extends the petitioners' argument in favor of reexamining the default hypothesis (LNT) and taking consideration of low-dose hormesis for two main reasons: 1) Failure to review the LNT hypothesis may jeopardize the NRC's mission to protect public health and safety; and 2) The National Research Council's guidelines for choosing adequate defaults indicate that the choice of low-dose default model is due for a reevaluation. PMID:26924276

  14. Acoustic radiation force expressed using complex phase shifts and momentum-transfer cross sections.

    PubMed

    Zhang, Likun; Marston, Philip L

    2016-08-01

    Acoustic radiation force is expressed using complex phase shifts of partial wave scattering functions and the momentum-transfer cross section, herein incorporated into acoustics from quantum mechanisms. Imaginary parts of the phase shifts represent dissipation in the object and/or in the boundary layer adjacent to the object. The formula simplifies the force as summation of functions of complex phase shifts of adjacent partial waves involving differences of real parts and sums of imaginary parts, providing an efficient way of exploring the force parameter-space. The formula for the force is proportional to a generalized momentum-transfer cross section for plane waves and no dissipation. PMID:27586777

  15. Radiation electrical conductivity of iron tricarbonyl PI-complexes with poly (styrenebutadiene) block copolymers

    SciTech Connect

    Tyutnev, A.P.; Abramov, V.N.; Bronshtein, L.M.; Pozhidaev, E.D.; Saenko, V.V.; Valetskii, P.M.

    1986-04-01

    This paper presents a thorough investigation of the radiation electrical conductivity of an iron-containing block copolymer in which the iron tricarbonyl fragments are built into the main chain of the polymer. The investigations were carried out with a DST-30 poly (styrenebutadiene) block copolymer (30 mass % styrene) and with iron tricarbonyl pi-complexes of this polymer DST-Fe (CO)/sub 3/. The iron tricarbonyl pi-complexes were obtained by reacting the block copolymer with iron dodecacarbonyl in a benzene medium with 10% ethanol in a stream of argon at 80 C. It was found that introduction of iron tricarbonyl into the DST-30 copolymer affects practically all properties of its nonstationary radiation electrical conductivity (NRE). The role of the rapid component of NRE increases with increasing Fe (CO)/sub 3/ content, while the decrease of the delayed component is somewhat slowed down.

  16. Upping the Ante of Text Complexity in the Common Core State Standards: Examining Its Potential Impact on Young Readers

    ERIC Educational Resources Information Center

    Hiebert, Elfrieda H.; Mesmer, Heidi Anne E.

    2013-01-01

    The Common Core Standards for the English Language Arts (CCSS) provide explicit guidelines matching grade-level bands (e.g., 2-3, 4-5) with targeted text complexity levels. The CCSS staircase accelerates text expectations for students across Grades 2-12 in order to close a gap in the complexity of texts typically used in high school and those of…

  17. Second cancer incidence risk estimates using BEIR VII models for standard and complex external beam radiotherapy for early breast cancer

    SciTech Connect

    Donovan, E. M.; James, H.; Bonora, M.; Yarnold, J. R.; Evans, P. M.

    2012-10-15

    Purpose: To compare organ specific cancer incidence risks for standard and complex external beam radiotherapy (including cone beam CT verification) following breast conservation surgery for early breast cancer.Method: Doses from breast radiotherapy and kilovoltage cone beam CT (CBCT) exposures were obtained from thermoluminescent dosimeter measurements in an anthropomorphic phantom in which the positions of radiosensitive organs were delineated. Five treatment deliveries were investigated: (i) conventional tangential field whole breast radiotherapy (WBRT), (ii) noncoplanar conformal delivery applicable to accelerated partial beast irradiation (APBI), (iii) two-volume simultaneous integrated boost (SIB) treatment, (iv) forward planned three-volume SIB, and (v) inverse-planned three volume SIB. Conformal and intensity modulated radiotherapy methods were used to plan the complex treatments. Techniques spanned the range from simple methods appropriate for patient cohorts with a low cancer recurrence risk to complex plans relevant to cohorts with high recurrence risk. Delineated organs at risk included brain, salivary glands, thyroid, contralateral breast, left and right lung, esophagus, stomach, liver, colon, and bladder. Biological Effects of Ionizing Radiation (BEIR) VII cancer incidence models were applied to the measured mean organ doses to determine lifetime attributable risk (LAR) for ages at exposure from 35 to 80 yr according to radiotherapy techniques, and included dose from the CBCT imaging. Results: All LAR decreased with age at exposure and were lowest for brain, thyroid, liver, and bladder (<0.1%). There was little dependence of LAR on radiotherapy technique for these organs and for colon and stomach. LAR values for the lungs for the three SIB techniques were two to three times those from WBRT and APBI. Uncertainties in the LAR models outweigh any differences in lung LAR between the SIB methods. Constraints in the planning of the SIB methods ensured that

  18. Second Cancer Incidence Risk Estimates using BEIR VII Models for Standard and Complex External Beam Radiotherapy for Early Breast Cancer

    PubMed Central

    Donovan, E M; James, H; Bonora, M; Yarnold, JR; Evans, PM

    2012-01-01

    Purpose To compare organ specific cancer incidence risks for standard and complex external beam radiotherapy including cone beam CT verification following breast conservation surgery for early breast cancer. Method Doses from breast radiotherapy and kilovoltage cone beam CT (CBCT) exposures were obtained from thermoluminescent dosimeter (TLD) measurements in an anthropomorphic phantom in which the positions of radiosensitive organs were delineated. Five treatment deliveries were investigated : (i) conventional tangential field whole breast radiotherapy (WBRT), (ii) non-coplanar conformal delivery applicable to accelerated partial beast irradiation (APBI), (iii) two-volume simultaneous integrated boost (SIB) treatment, (iv) forward planned three-volume SIB, (v) inverse-planned three volume SIB. Conformal and intensity modulated radiotherapy (IMRT) methods were used to plan the complex treatments. Techniques spanned the range from simple methods appropriate for patient cohorts with a low local cancer recurrence risk to complex plans relevant to cohorts with high recurrence risk. Delineated organs at risk included brain, salivary glands, thyroid, contra-lateral breast, left and right lung, oesophagus, stomach, liver, colon and bladder. Biological Effects of Ionising Radiation (BEIR) VII cancer incidence models were applied to the measured mean organ doses to determine Lifetime Attributable Risk (LAR) for ages at exposure from 35 to 80 years according to radiotherapy techniques, and included dose from the CBCT imaging. Results All LAR decreased with age at exposure and were lowest for brain, thyroid, liver and bladder (< 0.1%). There was little dependence of LAR on radiotherapy technique for these organs and for colon and stomach. LAR values for the lungs for the three SIB techniques were two to three times those from WBRT and APBI. Uncertainties in the LAR models outweigh any differences in lung LAR between the SIB methods. Constraints in the planning of the SIB

  19. Polarized radiative transfer in two-dimensional scattering medium with complex geometries by natural element method

    NASA Astrophysics Data System (ADS)

    Zhang, Yong; Kim, Yong-Jun; Yi, Hong-Liang; Xie, Ming; Tan, He-Ping

    2016-08-01

    The natural element method (NEM) is extended to solve the polarized radiative transfer problem in a two-dimensional scattering medium with complex geometries, in which the angular space is discretized by the discrete-ordinates approach, and the spatial discretization is conducted by the Galerkin weighted residuals approach. The Laplace interpolation scheme is adopted to obtain the shape functions used in the Galerkin weighted residuals approach. The NEM solution to the vector radiative transfer in a square enclosure filled with a Mie scattering medium is first examined to validate our program. We then study the polarized radiative transfer in two kinds of geometries filled with scattering medium which is equivalent to a suspension of latex spheres in water. Three sizes of spheres are considered. The results for non-dimensional polarized radiative flux along the boundaries and the angular distributions of the Stokes vector at specific positions are presented and discussed. For the complex geometry bounded by the square and circular object, numerical solutions are presented for the cases both with Lambertian (diffuse) reflection and with Fresnel reflection. Some interesting phenomenon are found and analyzed.

  20. Time-resolved GRB spectra in the complex radiation of synchrotron and Compton processes

    NASA Astrophysics Data System (ADS)

    Jiang, Y. G.; Hu, S. M.; Chen, X.; Li, K.; Guo, D. F.; Li, Y. T.; Li, H. Z.; Zhao, Y. Y.; Lin, H. N.; Chang, Z.

    2016-03-01

    Under the steady-state condition, the spectrum of electrons is investigated by solving the continuity equation under the complex radiation of both the synchrotron and Compton processes. The resulted gamma-ray burst (GRB) spectrum is a broken power law in both the fast and slow cooling phases. On the basis of this electron spectrum, the spectral indices of the Band function in four different phases are presented. In the complex radiation frame, the detail investigation on physical parameters reveals that three models can answer the α ˜ -1 problem, which are the synchrotron plus synchrotron self-Compton in the internal and the external shock models, and the synchrotron plus the external Compton processes in the external shock model. A possible marginal to fast cooling phase transition in GRB 080916C is discussed. The time-resolved spectra in different main pulses of GRB 100724B, GRB 100826A and GRB 130606B are investigated. We found that the flux is proportional to the peak energy in almost all main pulses. A significant (5σ) correlation for Fp ˜ Ep is evident the first main pulse of GRB 100826A, and three marginally significant (3σ) correlations Fp ˜ Ep are found in main pulses of GRB 100826A and GRB 130606B. The correlation between spectral index and Ep at 3 ˜ 4σ level are observed in the first main pulse of GRB 100826A. Such correlations are possible explained in the complex radiation scenario.

  1. Quasi-analytical treatment of spatially averaged radiation transfer in complex terrain

    NASA Astrophysics Data System (ADS)

    Löwe, H.; Helbig, N.

    2012-04-01

    We provide a new quasi-analytical method to compute the topographic influence on the effective albedo of complex topography as required for meteorological, land-surface or climate models. We investigate radiative transfer in complex terrain via the radiosity equation on isotropic Gaussian random fields. Under controlled approximations we derive expressions for domain averages of direct, diffuse and terrain radiation and the sky view factor. Domain averaged quantities are related to a type of level-crossing probability of the random field which is approximated by longstanding results developed for acoustic scattering at ocean boundaries. This allows us to express all non-local horizon effects in terms of a local terrain parameter, namely the mean squared slope. Emerging integrals are computed numerically and fit formulas are given for practical purposes. As an implication of our approach we provide an expression for the effective albedo of complex terrain in terms of the sun elevation angle, mean squared slope, the area averaged surface albedo, and the direct-to-diffuse ratio of solar radiation. As an application, we compute the effective albedo for the Swiss Alps and discuss possible generalizations of the method.

  2. Radiation thermometry standards at NMIJ from −30 °C to 2800 °C

    SciTech Connect

    Ishii, J.; Yamada, Y.; Sasajima, N.; Shimizu, Y.

    2013-09-11

    NMIJ has established a national standard scale in radiation thermometry from −30 °C to 2800 °C. At low temperatures from 160 °C down to −30 °C large aperture fluid-bath blackbodies have been constructed for the calibration of thermal infrared thermometers. In the range from 160 °C to 420 °C, the standard scale has been realized on 1.6 μm thermometers calibrated against In, Sn, and Zn blackbodies. A variable temperature blackbody using an air-bath furnace has recently been developed for direct comparison measurements of a 10 μm thermometer with a 1.6 μm thermometers up to 500 °C. In the higher range of the temperature scale, dissemination consists of three schemes: the range from 400 °C to 1100 °C by Zn, Al, Ag and Cu fixed-point blackbodies: above the Ag point by 0.9 μm and 0.65 μm thermometers: and above the Cu point by metal-carbon high-temperature fixed points.

  3. Assessing software upgrades, plan properties and patient geometry using intensity modulated radiation therapy (IMRT) complexity metrics

    SciTech Connect

    McGarry, Conor K.; Chinneck, Candice D.; O'Toole, Monica M.; O'Sullivan, Joe M; Prise, Kevin M.; Hounsell, Alan R.

    2011-04-15

    Purpose: The aim of this study is to compare the sensitivity of different metrics to detect differences in complexity of intensity modulated radiation therapy (IMRT) plans following upgrades, changes to planning parameters, and patient geometry. Correlations between complexity metrics are also assessed. Method: A program was developed to calculate a series of metrics used to describe the complexity of IMRT fields using monitor units (MUs) and multileaf collimator files: Modulation index (MI), modulation complexity score (MCS), and plan intensity map variation (PIMV). Each metric, including the MUs, was used to assess changes in beam complexity for six prostate patients, following upgrades in the inverse planning optimization software designed to incorporate direct aperture optimization (DAO). All beams were delivered to a 2D ionization chamber array and compared to those calculated using gamma analysis. Each complexity metric was then calculated for all beams, on a different set of six prostate IMRT patients, to assess differences between plans calculated using different minimum field sizes and different maximum segment numbers. Different geometries, including CShape, prostate, and head and neck phantoms, were also assessed using the metrics. Correlations between complexity metrics were calculated for 20 prostate IMRT patients. Results: MU, MCS, MI, and PIMV could all detect reduced complexity following an upgrade to the optimization leaf sequencer, although only MI and MCS could detect a reduction in complexity when one-step optimization (DAO) was employed rather than two-step optimization. All metrics detected a reduction in complexity when the minimum field size was increased from 1 to 4 cm and all apart from PIMV detected reduced complexity when the number of segments was significantly reduced. All metrics apart from MI showed differences in complexity depending on the treatment site. Significant correlations exist between all metrics apart from MI and PIMV for

  4. Investigation into the effects of VHF and UHF band radiation on Hewlett-Packard (HP) Cesium Beam Frequency Standards

    NASA Technical Reports Server (NTRS)

    Dickens, Andrew

    1995-01-01

    This paper documents an investigation into reports which have indicated that exposure to VHF and UHF band radiation has adverse effects on the frequency stability of HP cesium beam frequency standards. Tests carried out on the basis of these reports show that sources of VHF and UHF radiation such as two-way hand held police communications devices do cause reproducible adverse effects. This investigation examines reproducible effects and explores possible causes.

  5. Radiation Protection. Measurement of radioactivity in the environment - Air- radon 222. A proposed ISO standard.

    NASA Astrophysics Data System (ADS)

    Gillmore, G.; Woods, M.

    2009-04-01

    Radon isotopes (222, 220, 219) are radioactive gases produced by the disintegration of radium isotopes 226, 224 and 223, which are decay products of uranium238, thorium232 and uranium235 respectively. All are found in the earth's crust. Solid elements, also radioactive, are produced by radon disintegration. Radon is classed as a rare gas in the periodic table of elements, along with helium, argon, neon, krypton and xenon. When disintegrating, radon emits alpha particles and generates solid decay products, which are also radioactive (polonium, bismuth, lead etc.). The potential danger of radon lies in its solid decay products rather than the gas itself. Whether or not they are attached aerosols, radon decay products can be inhaled and deposited in the bronchopulmonary tree to varying depths according to their size. Radon today is considered to be the main source of human exposure to natural radiation. At the international level, radon accounts for 52% of global average exposure to natural radiation. Isotope 222 (48%) is far more significant than isotope 220 (4%), whilst isotope 219 is considered as negligible. Exposure to radon varies considerably from one region to another, depending on factors such as weather conditions, and underlying geology. Activity concentration can therefore vary by a factor of 10 or even a 100 from one period of time to the next and from one area to another. There are many ways of measuring the radon 222 activity concentration and the potential alpha energy concentration of its short-lived decay products. Measuring techniques fall into three categories: - spot measurement methods; continuous measurement; integrated measurement. The proposed ISO (International Organisation for Standardisation) document suggests guidelines for measuring radon222 activity concentration and the potential alpha energy concentration of its short-lived decay products in a free (environment) and confined (buildings) atmosphere. The target date for availability of

  6. A Comparison of Radiation Dose Between Standard and 3D Angiography in Congenital Heart Disease

    PubMed Central

    Manica, João Luiz Langer; Borges, Mônica Scott; de Medeiros, Rogério Fachel; Fischer, Leandro dos Santos; Broetto, Gabriel; Rossi, Raul Ivo

    2014-01-01

    Background The use of three-dimensional rotational angiography (3D-RA) to assess patients with congenital heart diseases appears to be a promising technique despite the scarce literature available. Objectives The objective of this study was to describe our initial experience with 3D-RA and to compare its radiation dose to that of standard two-dimensional angiography (2D-SA). Methods Between September 2011 and April 2012, 18 patients underwent simultaneous 3D-RA and 2D-SA during diagnostic cardiac catheterization. Radiation dose was assessed using the dose-area-product (DAP). Results The median patient age and weight were 12.5 years and 47.5 Kg, respectively. The median DAP of each 3D-RA acquisition was 1093µGy.m2 and 190µGy.m2 for each 2D-SA acquisition (p<0.01). In patients weighing more than 45Kg (n=7), this difference was attenuated but still significant (1525 µGy.m2 vs.413µGy.m2, p=0.01). No difference was found between one 3D-RA and three 2D-SA (1525µGy.m2 vs.1238 µGy.m2, p = 0.575) in this population. This difference was significantly higher in patients weighing less than 45Kg (n=9) (713µGy.m2 vs.81µGy.m2, P = 0.008), even when comparing one 3D-RA with three 2D-SA (242µGy.m2, respectively, p<0.008). 3D-RA was extremely useful for the assessment of conduits of univentricular hearts, tortuous branches of the pulmonary artery, and aorta relative to 2D-SA acquisitions. Conclusions The radiation dose of 3D-RA used in our institution was higher than those previously reported in the literature and this difference was more evident in children. This type of assessment is of paramount importance when starting to perform 3D-RA. PMID:25211313

  7. Addition of Bevacizumab to Standard Radiation Therapy and Daily Temozolomide Is Associated With Minimal Toxicity in Newly Diagnosed Glioblastoma Multiforme

    SciTech Connect

    Vredenburgh, James J.; Desjardins, Annick; Kirkpatrick, John P.; Reardon, David A.; Peters, Katherine B.; Herndon, James E.; Marcello, Jennifer; Bailey, Leighann; Threatt, Stevie; Sampson, John; Friedman, Allan; Friedman, Henry S.

    2012-01-01

    Purpose: To determine the safety of the addition of bevacizumab to standard radiation therapy and daily temozolomide for newly diagnosed glioblastoma multiforme (GBM). Methods and Materials: A total of 125 patients with newly diagnosed GBM were enrolled in the study, and received standard radiation therapy and daily temozolomide. All patients underwent a craniotomy and were at least 2 weeks postoperative. Radiation therapy was administered in 1.8-Gy fractions, with the clinical target volume for the primary course treated to a dose of 45 to 50.4 Gy, followed by a boost of 9 to 14.4 Gy, to a total dose of 59.4 Gy. Patients received temozolomide at 75 mg/m{sup 2} daily throughout the course of radiation therapy. Bevacizumab was given at 10 mg/kg intravenously every 14 days, beginning a minimum of 4 weeks postoperatively. Results: Of the 125 patients, 120 (96%) completed the protocol-specified radiation therapy. Five patients had to stop the protocol therapy, 2 patients with pulmonary emboli, and 1 patient each with a Grade 2 central nervous system hemorrhage, Grade 4 pancytopenia, and wound dehiscence requiring surgical intervention. All 5 patients ultimately finished the radiation therapy. After radiation therapy, 3 patients had progressive disease, 2 had severe fatigue and decreased performance status, 1 patient had a colonic perforation, and 1 had a rectal fissure; these 7 patients therefore did not proceed with the protocol-specified adjuvant temozolomide, bevacizumab, and irinotecan. However, 113 patients (90%) were able to continue on study. Conclusions: The addition of bevacizumab to standard radiation therapy and daily temozolomide was found to be associated with minimal toxicity in patients newly diagnosed with GBM.

  8. Toward Standardized Acoustic Radiation Force (ARF)-Based Ultrasound Elasticity Measurements With Robotic Force Control

    PubMed Central

    Kumar, Shalki; Lily, Kuo; Sen, H. Tutkun; Iordachita, Iulian; Kazanzides, Peter

    2016-01-01

    Objective Acoustic radiation force (ARF)-based approaches to measure tissue elasticity require transmission of a focused high-energy acoustic pulse from a stationary ultrasound probe and ultrasound-based tracking of the resulting tissue displacements to obtain stiffness images or shear wave speed estimates. The method has established benefits in biomedical applications such as tumor detection and tissue fibrosis staging. One limitation, however, is the dependence on applied probe pressure, which is difficult to control manually and prohibits standardization of quantitative measurements. To overcome this limitation, we built a robot prototype that controls probe contact forces for shear wave speed quantification. Methods The robot was evaluated with controlled force increments applied to a tissue-mimicking phantom and in vivo abdominal tissue from three human volunteers. Results The root-mean-square error between the desired and measured forces was 0.07 N in the phantom and higher for the fatty layer of in vivo abdominal tissue. The mean shear wave speeds increased from 3.7 to 4.5 m/s in the phantom and 1.0 to 3.0 m/s in the in vivo fat for compressive forces ranging from 2.5 to 30 N. The standard deviation of shear wave speeds obtained with the robotic approach were low in most cases (< 0.2 m/s) and comparable to that obtained with a semiquantitative landmark-based method. Conclusion Results are promising for the introduction of robotic systems to control the applied probe pressure for ARF-based measurements of tissue elasticity. Significance This approach has potential benefits in longitudinal studies of disease progression, comparative studies between patients, and large-scale multidimensional elasticity imaging. PMID:26552071

  9. Generics Substitution, Bioequivalence Standards, and International Oversight: Complex Issues Facing the FDA.

    PubMed

    Bate, Roger; Mathur, Aparna; Lever, Harry M; Thakur, Dinesh; Graedon, Joe; Cooperman, Tod; Mason, Preston; Fox, Erin R

    2016-03-01

    The regulations for assessing the quality of generic drugs and their bioequivalence to innovator products are outdated and need to be substantially modernized. There are multiple reasons why these changes are needed, including: (i) the regulations remain largely unchanged since the passage of the Hatch-Waxman Act in 1984; (ii) medication therapies have become substantially more complex over the three decades since the passage of the Act; (iii) a switch from an innovator drug to a generic drug, or switching from one generic to another, is not a benign process - there is substantial clinical professional judgment involved and in some instances these decisions should be better informed; and (iv) pharmaceutical ingredients for finished products, whether innovator or generic, are from multiple sources of supply, adding variability in their production, and which may not be accounted for in specification tolerances. When these elements are viewed together, they clearly suggest that more transparency of responsible manufacturers in product labels and updated standards for bioequivalence are required. PMID:26687297

  10. Abelian gauge extension of the standard model: Dark matter and radiative neutrino mass

    NASA Astrophysics Data System (ADS)

    Borah, Debasish; Adhikari, Rathin

    2012-05-01

    We study a simple extension of the standard model where the gauge group is extended by an additional U(1)X gauge symmetry. Neutrino mass arises both at tree level as well as radiatively by the anomaly-free addition of one singlet fermion NR and two triplet fermions Σ1R, Σ2R with suitable Higgs scalars. The spontaneous gauge symmetry breaking is achieved in a way that results in a residual Z2 symmetry and hence provides a stable cold dark matter candidate. We study the possible dark matter candidates in this model by incorporating the constraints from cosmology as well as direct detection experiments. We discuss both low- and high-mass (from GeV to the TeV scale) regimes of fermionic and scalar dark matter candidates in the model. We show that scalar dark matter relic density, although not significantly affected by the presence or absence of annihilation into U(1)X gauge boson pairs, is however affected by choice of U(1)X gauge charges. We discuss the neutrino mass phenomenology and its compatibility with the allowed dark matter mass ranges and we also comment on the implications of the model on Higgs signatures at colliders including those related to the fourth fermion generation.

  11. Alanine-EPR as a transfer standard dosimetry system for low energy X radiation

    NASA Astrophysics Data System (ADS)

    Khoury, H. J.; da Silva, E. J.; Mehta, K.; de Barros, V. S.; Asfora, V. K.; Guzzo, P. L.; Parker, A. G.

    2015-11-01

    The purpose of this paper is to evaluate the use of alanine-EPR as a transfer standard dosimetry system for low energy X radiation, such as that in RS-2400, which operates in the range from 25 to 150 kV and 2 to 45 mA. Two types of alanine dosimeters were investigated. One is a commercial alanine pellets from Aérial-Centre de Ressources Technologiques, France and one was prepared in our laboratory (LMRI-DEN/UFPE). The EPR spectra of the irradiated dosimeters were recorded in the Nuclear Energy Department of UFPE, using a Bruker EMX10 EPR spectrometer operating in the X-band. The alanine-EPR dosimetry system was calibrated in the range of 20-220 Gy in this X-ray field, against an ionization chamber calibrated at the relevant X-ray energy with traceability to PTB. The results showed that both alanine dosimeters presented a linear dose response the same sensitivity, when the EPR signal was normalized to alanine mass. The total uncertainty in the measured dose was estimated to be about 3%. The results indicate that it is possible to use the alanine-EPR dosimetry system for validation of a low-energy X ray irradiator, such as RS-2400.

  12. Secondary calibration laboratory for ionizing radiation laboratory accreitation program National Institute of Standards and Technology National Voluntary Laboratory Accreditation Program

    SciTech Connect

    Martin, P.R.

    1993-12-31

    This paper presents an overview of the procedures and requirements for accreditation under the Secondary Calibration Laboratory for Ionizing Radiation Program (SCLIR LAP). The requirements for a quality system, proficiency testing and the onsite assessment are discussed. The purpose of the accreditation program is to establish a network of secondary calibration laboratories that can provide calibrations traceable to the primary national standards.

  13. Radiation injury is a potentially serious complication to fluoroscopically-guided complex interventions

    PubMed Central

    Wagner, LK

    2007-01-01

    Radiation-induced injury to skin is an infrequent but potentially serious complication to complex fluoroscopically-guided interventional procedures. Due to a lack of experience with such injuries, the medical community has found fluoroscopically-induced injuries difficult to diagnose. Injuries have occurred globally in many countries. Serious injuries most frequently occur on the back but have also occurred on the neck, buttocks and anterior of the chest. Severities of injuries range from skin rashes and epilation to necrosis of the skin and its underlying structures. This article reviews the characteristics of these injuries and some actions that can be taken to reduce their likelihood or seriousness. PMID:21614271

  14. Retrograde dilation of a complex radiation-induced esophageal stricture through percutaneous gastrostomy.

    PubMed

    Eminler, A T; Uslan, M I; Köksal, A Ş; Guven, M; Parlak, E

    2015-06-01

    Upper esophageal strictures occur in approximately 3-4% of patients who receive radiotherapy for head and neck cancers. The standart initial treatment is dilation by using bougie or through-the-scope balloon dilators. Endoscopic treatment requires the passage of a guidewire through the stricture which cannot be accomplished in some of the patients with complex strictures. Retrograde dilation of esophageal strictures through a mature percutaneous gastrostomy tract have been reported in a limited number of cases and small case series up to date and can be considered as a rescue treatment before considering surgery in such patients. Herein we report retrograde dilatation of a radiation-induced complex esophageal stricture through the percutaneous gastrostomy tract in a patient with operated larynx cancer. PMID:26151697

  15. Propagating self-sustained annealing of radiation-induced interstitial complexes

    NASA Astrophysics Data System (ADS)

    Bokov, P. M.; Selyshchev, P. A.

    2016-02-01

    A propagating self-sustained annealing of radiation induced defects as a result of thermal-concentration instability is studied. The defects that are considered in the model are complexes. Each of them consists of one atom of impunity and of one interstitial atom. Crystal with defects has extra energy which is transformed into heat during defect annealing. Simulation of the auto-wave of annealing has been performed. The front and the speed of the auto-wave have been obtained. It is shown that annealing occurs in a narrow region of time and space. There are two kinds of such annealing behaviour. In the first case the speed of the auto-wave oscillates near its constant mean value and the front of temperature oscillates in a complex way. In the second case the speed of propagation is constant and fronts of temperature and concentration look like sigmoid functions.

  16. Opportunities for radiation-dose optimization through standardized analytics and decision support.

    PubMed

    Reiner, Bruce I

    2014-11-01

    Although the potential for adverse clinical outcomes related to medical radiation have been well documented for over a century, several relatively recent trends have increased awareness of radiation safety in medical imaging. These include expanded CT applications and utilization, increased patient attention on radiation carcinogenesis, and a wide array of legislative and societal radiation initiatives, created partly in response to media reports of CT-induced radiation complications. With this heightened radiation awareness and scrutiny comes a unique and timely opportunity for the collective medical-imaging community to incorporate comparative radiation metrics and analysis directly into routine workflow and reporting. If properly performed, a number of benefits could in theory be derived, including improved clinical outcomes, creation of data-driven best practice guidelines, opportunities for enhanced education and research, dose-reduction technology innovation, and reversal of existing commoditization trends. PMID:25163408

  17. Performance and Complexity Co-evaluation of the Advanced Video Coding Standard for Cost-Effective Multimedia Communications

    NASA Astrophysics Data System (ADS)

    Saponara, Sergio; Denolf, Kristof; Lafruit, Gauthier; Blanch, Carolina; Bormans, Jan

    2004-12-01

    The advanced video codec (AVC) standard, recently defined by a joint video team (JVT) of ITU-T and ISO/IEC, is introduced in this paper together with its performance and complexity co-evaluation. While the basic framework is similar to the motion-compensated hybrid scheme of previous video coding standards, additional tools improve the compression efficiency at the expense of an increased implementation cost. As a first step to bridge the gap between the algorithmic design of a complex multimedia system and its cost-effective realization, a high-level co-evaluation approach is proposed and applied to a real-life AVC design. An exhaustive analysis of the codec compression efficiency versus complexity (memory and computational costs) project space is carried out at the early algorithmic design phase. If all new coding features are used, the improved AVC compression efficiency (up to 50% compared to current video coding technology) comes with a complexity increase of a factor 2 for the decoder and larger than one order of magnitude for the encoder. This represents a challenge for resource-constrained multimedia systems such as wireless devices or high-volume consumer electronics. The analysis also highlights important properties of the AVC framework allowing for complexity reduction at the high system level: when combining the new coding features, the implementation complexity accumulates, while the global compression efficiency saturates. Thus, a proper use of the AVC tools maintains the same performance as the most complex configuration while considerably reducing complexity. The reported results provide inputs to assist the profile definition in the standard, highlight the AVC bottlenecks, and select optimal trade-offs between algorithmic performance and complexity.

  18. Influence of symmetry on the luminescence and radiative lifetime of nine-coordinate europium complexes.

    PubMed

    Shavaleev, Nail M; Eliseeva, Svetlana V; Scopelliti, Rosario; Bünzli, Jean-Claude G

    2015-09-21

    Homoleptic mononuclear nine-coordinate lanthanum(III) and europium(III) tris-complexes [Ln(N(∧)N(∧)O)3]·nH2O with two tridentate N-benzylbenzimidazole pyridine-2-carboxylates exhibit a rare C3-symmetry of the lanthanide coordination polyhedron in the solid state, as confirmed by luminescence spectroscopy and by X-ray crystallography (the three N(∧)N(∧)O ligands are arranged "up-up-up" around the lanthanide ion). The symmetry, however, is changed to the more common C1 upon dissolution of the complexes in dichloromethane, as revealed by luminescence spectroscopy (the three ligands are likely to be arranged "up-up-down"). The new europium complexes emit efficient ligand-sensitized metal-centered luminescence with excited-state lifetimes of 1.56-2.18 ms and quantum yields of 25-41% in the solid and in solution. The change of the symmetry from (a higher) C3 to (a lower) C1 alters the luminescence spectrum, shortens the radiative lifetime, and increases the luminescence efficiency of the europium complexes. PMID:26340341

  19. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation

    PubMed Central

    Zhang, Xurui; Ye, Caiyong; Sun, Fang; Wei, Wenjun; Hu, Burong; Wang, Jufang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92–1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. We observed less efficient repair when DNA damage was induced by heavy ions compared with X-rays and most of the irreparable damage was complex of single strand breaks and double strand breaks, while DNA damage induced by X-rays was mostly repaired in 24 hours and the remained damage was preferentially associated with telomeric DNA. Our results suggest that DNA damage induced by heavy ion is often complex and difficult to repair, thus presents as persistent DNA damage and pushes the cell into senescence. In contrast, persistent DNA damage induced by X-rays is preferentially associated with telomeric DNA and the telomere-favored persistent DNA damage contributes to X-rays induced cellular senescence. These findings provide new insight into the understanding of high relative biological effectiveness of heavy ions relevant to cancer therapy and space radiation research. PMID:27187621

  20. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation.

    PubMed

    Zhang, Xurui; Ye, Caiyong; Sun, Fang; Wei, Wenjun; Hu, Burong; Wang, Jufang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92-1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. We observed less efficient repair when DNA damage was induced by heavy ions compared with X-rays and most of the irreparable damage was complex of single strand breaks and double strand breaks, while DNA damage induced by X-rays was mostly repaired in 24 hours and the remained damage was preferentially associated with telomeric DNA. Our results suggest that DNA damage induced by heavy ion is often complex and difficult to repair, thus presents as persistent DNA damage and pushes the cell into senescence. In contrast, persistent DNA damage induced by X-rays is preferentially associated with telomeric DNA and the telomere-favored persistent DNA damage contributes to X-rays induced cellular senescence. These findings provide new insight into the understanding of high relative biological effectiveness of heavy ions relevant to cancer therapy and space radiation research. PMID:27187621

  1. Calculation of the radiative heat exchange in a conical cavity of complex configuration with an absorptive medium

    NASA Technical Reports Server (NTRS)

    Surinov, Y. A.; Fedyanin, V. E.

    1975-01-01

    The generalized zonal method is used to calculate the distribution of the temperature factor on the lateral surface of a conical cavity of complex configuration (a Laval nozzle) containing an absorptive medium. The highest values of the radiation density occur on the converging part of the lateral surface of the complex conical cavity (Laval nozzle).

  2. Evaluation of digital breast tomosynthesis reconstruction algorithms using synchrotron radiation in standard geometry

    SciTech Connect

    Bliznakova, K.; Kolitsi, Z.; Speller, R. D.; Horrocks, J. A.; Tromba, G.; Pallikarakis, N.

    2010-04-15

    Purpose: In this article, the image quality of reconstructed volumes by four algorithms for digital tomosynthesis, applied in the case of breast, is investigated using synchrotron radiation. Methods: An angular data set of 21 images of a complex phantom with heterogeneous tissue-mimicking background was obtained using the SYRMEP beamline at ELETTRA Synchrotron Light Laboratory, Trieste, Italy. The irradiated part was reconstructed using the multiple projection algorithm (MPA) and the filtered backprojection with ramp followed by hamming windows (FBR-RH) and filtered backprojection with ramp (FBP-R). Additionally, an algorithm for reducing the noise in reconstructed planes based on noise mask subtraction from the planes of the originally reconstructed volume using MPA (MPA-NM) has been further developed. The reconstruction techniques were evaluated in terms of calculations and comparison of the contrast-to-noise ratio (CNR) and artifact spread function. Results: It was found that the MPA-NM resulted in higher CNR, comparable with the CNR of FBP-RH for high contrast details. Low contrast objects are well visualized and characterized by high CNR using the simple MPA and the MPA-NM. In addition, the image quality of the reconstructed features in terms of CNR and visual appearance as a function of the initial number of projection images and the reconstruction arc was carried out. Slices reconstructed with more input projection images result in less reconstruction artifacts and higher detail CNR, while those reconstructed from projection images acquired in reduced angular range causes pronounced streak artifacts. Conclusions: Of the reconstruction algorithms implemented, the MPA-NM and MPA are a good choice for detecting low contrast objects, while the FBP-RH, FBP-R, and MPA-NM provide high CNR and well outlined edges in case of microcalcifications.

  3. A Standard Setting Method Designed for Complex Performance Assessments with Multiple Performance Categories: Categorical Assignments of Student Work.

    ERIC Educational Resources Information Center

    Plake, Barbara S.; Hambleton, Ronald K.

    This paper reports on a standard-setting method designed for complex performance assessments with multiple performance categories. The method studied, the Analytical Judgment Method, involves panelists' making analytical classification decisions for each of the test's components individually. It also allows for discussion and reconsideration of…

  4. Experimental and theoretical study of organometallic radiation-protective materials adapted to radiation sources with a complex isotopic composition

    NASA Astrophysics Data System (ADS)

    Russkikh, I. M.; Seleznev, E. N.; Tashlykov, O. L.; Shcheklein, S. E.

    2015-12-01

    The significance of optimizing the content of components of a radiation-protective material, which is determined by the isotopic composition of radioactive contamination, depending on the reactor type, operating time, and other factors is demonstrated. The results of computational and experimental investigation of the gamma-radiation attenuation capacity of homogenous radiation-protective materials with different fillers are reported.

  5. Experimental and theoretical study of organometallic radiation-protective materials adapted to radiation sources with a complex isotopic composition

    SciTech Connect

    Russkikh, I. M.; Seleznev, E. N.; Tashlykov, O. L. Shcheklein, S. E.

    2015-12-15

    The significance of optimizing the content of components of a radiation-protective material, which is determined by the isotopic composition of radioactive contamination, depending on the reactor type, operating time, and other factors is demonstrated. The results of computational and experimental investigation of the gamma-radiation attenuation capacity of homogenous radiation-protective materials with different fillers are reported.

  6. 42 CFR Appendix E to Part 75 - Standards for Accreditation of Educational Programs for Radiation Therapy Technologists

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...; (j) Radiation physics; (k) Radiation protection; (l) Radiation oncology technique; (m) Radiographic... knowledge of radiation physics in radiation interactions and radiation protection techniques; (f) Provide...) Successful completion or challenge of courses in the following prerequisite content areas: —Radiation...

  7. 42 CFR Appendix E to Part 75 - Standards for Accreditation of Educational Programs for Radiation Therapy Technologists

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...; (j) Radiation physics; (k) Radiation protection; (l) Radiation oncology technique; (m) Radiographic... knowledge of radiation physics in radiation interactions and radiation protection techniques; (f) Provide...) Successful completion or challenge of courses in the following prerequisite content areas: —Radiation...

  8. 42 CFR Appendix E to Part 75 - Standards for Accreditation of Educational Programs for Radiation Therapy Technologists

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...; (j) Radiation physics; (k) Radiation protection; (l) Radiation oncology technique; (m) Radiographic... knowledge of radiation physics in radiation interactions and radiation protection techniques; (f) Provide...) Successful completion or challenge of courses in the following prerequisite content areas: —Radiation...

  9. 42 CFR Appendix E to Part 75 - Standards for Accreditation of Educational Programs for Radiation Therapy Technologists

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...; (j) Radiation physics; (k) Radiation protection; (l) Radiation oncology technique; (m) Radiographic... knowledge of radiation physics in radiation interactions and radiation protection techniques; (f) Provide...) Successful completion or challenge of courses in the following prerequisite content areas: —Radiation...

  10. 42 CFR Appendix E to Part 75 - Standards for Accreditation of Educational Programs for Radiation Therapy Technologists

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...; (j) Radiation physics; (k) Radiation protection; (l) Radiation oncology technique; (m) Radiographic... knowledge of radiation physics in radiation interactions and radiation protection techniques; (f) Provide...) Successful completion or challenge of courses in the following prerequisite content areas: —Radiation...

  11. MDP: A Deinococcus Mn2+-Decapeptide Complex Protects Mice from Ionizing Radiation.

    PubMed

    Gupta, Paridhi; Gayen, Manoshi; Smith, Joan T; Gaidamakova, Elena K; Matrosova, Vera Y; Grichenko, Olga; Knollmann-Ritschel, Barbara; Daly, Michael J; Kiang, Juliann G; Maheshwari, Radha K

    2016-01-01

    The radioprotective capacity of a rationally-designed Mn2+-decapeptide complex (MDP), based on Mn antioxidants in the bacterium Deinococcus radiodurans, was investigated in a mouse model of radiation injury. MDP was previously reported to be extraordinarily radioprotective of proteins in the setting of vaccine development. The peptide-component (DEHGTAVMLK) of MDP applied here was selected from a group of synthetic peptides screened in vitro for their ability to protect cultured human cells and purified enzymes from extreme damage caused by ionizing radiation (IR). We show that the peptides accumulated in Jurkat T-cells and protected them from 100 Gy. MDP preserved the activity of T4 DNA ligase exposed to 60,000 Gy. In vivo, MDP was nontoxic and protected B6D2F1/J (female) mice from acute radiation syndrome. All irradiated mice treated with MDP survived exposure to 9.5 Gy (LD70/30) in comparison to the untreated mice, which displayed 63% lethality after 30 days. Our results show that MDP provides early protection of white blood cells, and attenuates IR-induced damage to bone marrow and hematopoietic stem cells via G-CSF and GM-CSF modulation. Moreover, MDP mediated the immunomodulation of several cytokine concentrations in serum including G-CSF, GM-CSF, IL-3 and IL-10 during early recovery. Our results present the necessary prelude for future efforts towards clinical application of MDP as a promising IR countermeasure. Further investigation of MDP as a pre-exposure prophylactic and post-exposure therapeutic in radiotherapy and radiation emergencies is warranted. PMID:27500529

  12. MDP: A Deinococcus Mn2+-Decapeptide Complex Protects Mice from Ionizing Radiation

    PubMed Central

    Smith, Joan T.; Gaidamakova, Elena K.; Matrosova, Vera Y.; Grichenko, Olga; Knollmann-Ritschel, Barbara; Daly, Michael J.; Kiang, Juliann G.

    2016-01-01

    The radioprotective capacity of a rationally-designed Mn2+-decapeptide complex (MDP), based on Mn antioxidants in the bacterium Deinococcus radiodurans, was investigated in a mouse model of radiation injury. MDP was previously reported to be extraordinarily radioprotective of proteins in the setting of vaccine development. The peptide-component (DEHGTAVMLK) of MDP applied here was selected from a group of synthetic peptides screened in vitro for their ability to protect cultured human cells and purified enzymes from extreme damage caused by ionizing radiation (IR). We show that the peptides accumulated in Jurkat T-cells and protected them from 100 Gy. MDP preserved the activity of T4 DNA ligase exposed to 60,000 Gy. In vivo, MDP was nontoxic and protected B6D2F1/J (female) mice from acute radiation syndrome. All irradiated mice treated with MDP survived exposure to 9.5 Gy (LD70/30) in comparison to the untreated mice, which displayed 63% lethality after 30 days. Our results show that MDP provides early protection of white blood cells, and attenuates IR-induced damage to bone marrow and hematopoietic stem cells via G-CSF and GM-CSF modulation. Moreover, MDP mediated the immunomodulation of several cytokine concentrations in serum including G-CSF, GM-CSF, IL-3 and IL-10 during early recovery. Our results present the necessary prelude for future efforts towards clinical application of MDP as a promising IR countermeasure. Further investigation of MDP as a pre-exposure prophylactic and post-exposure therapeutic in radiotherapy and radiation emergencies is warranted. PMID:27500529

  13. ["Epistemic Negotiations" and the Pluralism of the Radiation Protection Regime: The Determination of Radiation Protection Standards for the General Population in the Early Years After World War II].

    PubMed

    Higuchi, Toshihiro

    2015-10-01

    Radiation protection standards for the general population have constituted one of the most controversial subjects in the history of atomic energy uses. This paper reexamines the process in which the first such standards evolved in the early postwar period. While the existing literature has emphasized a "collusion" between the standard-setters and users, the paper seeks to examine the horizontal relationship among the standard-setters. It first examines a series of expert consultations between the United States and the United Kingdom. Representing a different configuration of power and interest, the two failed to agree on the assessment of genetic damage and cancer induction whose occurrence might have no threshold and therefore be dependent on the population size. This stalemate prevented the International Commission on Radiological Protection (ICRP), established in 1950, from formulating separate guidelines for the general public. Situations radically changed when the Bikini incident in 1954 led to the creation of more scientific panels. One such panel under the U.S. Academy of Sciences enabled the geneticists to bridge their internal divide, unanimously naming 100 mSv as the genetically permissible dose for the general population. Not to be outdone, ICRP publicized its own guidelines for the same purpose. The case examined in this paper shows that the standard-setting process is best understood as a series of "epistemic negotiations" among and within the standard-setters, whose agendas were determined from the outset but whose outcomes were not. PMID:26875309

  14. Wrestling With a Paradox: Complexity in Interoperability Standards Making for Healthcare Information Systems

    NASA Astrophysics Data System (ADS)

    Pittaway, Jeff; Archer, Norm

    Medical interventions are often delayed or erroneous when information needed for diagnosing or prescribing is missing or unavailable. In support of increased information flows, the healthcare industry has invested substantially in standards intended to specify, routinize, and make uniform the type and format of medical information in clinical healthcare information systems such as Electronic Medical Record systems (EMRs). However, fewer than one in four Canadian physicians have adopted EMRs. Deeper analysis illustrates that physicians may perceive value in standardized EMRs when they need to exchange information in highly structured situations among like participants and like environments. However, standards present restrictive barriers to practitioners when they face equivocal situations, unforeseen contingencies, or exchange information across different environments. These barriers constitute a compelling explanation for at least part of the observed low EMR adoption rates. Our recommendations to improve the perceived value of standardized clinical information systems espouse re-conceptualizing the role of standards to embrace greater flexibility in some areas.

  15. Locoregional Outcomes of Inflammatory Breast Cancer Patients Treated With Standard Fractionation Radiation and Daily Skin Bolus in the Taxane Era

    SciTech Connect

    Damast, Shari; Ho, Alice Y.; Montgomery, Leslie; Fornier, Monica N.; Ishill, Nicole; Elkin, Elena; Beal, Kathryn; McCormick, Beryl

    2010-07-15

    Purpose: To assess locoregional outcomes of inflammatory breast cancer (IBC) patients who received standard fractionation radiation with daily skin bolus and taxanes as part of combined-modality therapy (CMT). Methods and Materials: We retrospectively reviewed the charts of 107 patients diagnosed with IBC between January 1995 and March 2006 who presented to our department for adjuvant radiation therapy (RT). Results: All patients received chemotherapy (95% anthracycline and 95% taxane), modified radical mastectomy, and RT to the chest wall and regional lymphatics using standard fractionation to 50 Gy and daily skin bolus. The RT to the chest wall was delivered via electrons (55%) or photons (45%) in daily fractions of 180 cGy (73%) or 200 cGy (27%). Scar boost was performed in 11%. A majority (84%) of patients completed the prescribed treatment. Median follow-up was 47 months (range, 10-134 months). Locoregional control (LRC) at 3 years and 5 years was 90% and 87%, respectively. Distant metastases-free survival (DMFS) at 3 years and 5 years was 61% and 47%, respectively. Conclusions: Excellent locoregional control was observed in this population of IBC patients who received standard fractionation radiation with daily skin bolus and taxanes as part of combined-modality therapy. Distant metastases-free survival remains a significant therapeutic challenge.

  16. Bond Fission and Non-Radiative Decay in Iridium(III) Complexes.

    PubMed

    Zhou, Xiuwen; Burn, Paul L; Powell, Benjamin J

    2016-06-01

    We investigate the role of metal-ligand bond fission in the nonradiative decay of excited states in iridium(III) complexes with applications in blue organic light-emitting diodes (OLEDs). We report density functional theory (DFT) calculations of the potential energy surfaces upon lengthening an iridium-nitrogen (Ir-N) bond. In all cases we find that for bond lengths comparable to those of the ground state the lowest energy state is a triplet with significant metal-to-ligand change transfer character ((3)MLCT). But, as the Ir-N bond is lengthened there is a sudden transition to a regime where the lowest excited state is a triplet with significant metal centered character ((3)MC). Time-dependent DFT relativistic calculations including spin-orbit coupling perturbatively show that the radiative decay rate from the (3)MC state is orders of magnitude slower than that from the (3)MLCT state. The calculated barrier height between the (3)MLCT and (3)MC regimes is clearly correlated with previously measured nonradiative decay rates, suggesting that thermal population of the (3)MC state is the dominant nonradiative decay process at ambient temperature. In particular, fluorination both drives the emission of these complexes to a deeper blue color and lowers the (3)MLCT-(3)MC barrier. If the Ir-N bond is shortened in the (3)MC state another N atom is pushed away from the Ir, resulting in the breaking of this bond, suggesting that once the Ir-N bond breaks the damage to the complex is permanent-this will have important implications for the lifetimes of devices using this type of complex as the active material. The consequences of these results for the design of more efficient blue phosphors for OLED applications are discussed. PMID:27175618

  17. Numerical simulation of acoustofluidic manipulation by radiation forces and acoustic streaming for complex particles.

    PubMed

    Hahn, Philipp; Leibacher, Ivo; Baasch, Thierry; Dual, Jurg

    2015-11-21

    The numerical prediction of acoustofluidic particle motion is of great help for the design, the analysis, and the physical understanding of acoustofluidic devices as it allows for a simple and direct comparison with experimental observations. However, such a numerical setup requires detailed modeling of the acoustofluidic device with all its components and thorough understanding of the acoustofluidic forces inducing the particle motion. In this work, we present a 3D trajectory simulation setup that covers the full spectrum, comprising a time-harmonic device model, an acoustic streaming model of the fluid cavity, a radiation force simulation, and the calculation of the hydrodynamic drag. In order to make quantitatively accurate predictions of the device vibration and the acoustic field, we include the viscous boundary layer damping. Using a semi-analytical method based on Nyborg's calculations, the boundary-driven acoustic streaming is derived directly from the device simulation and takes into account cavity wall vibrations which have often been neglected in the literature. The acoustic radiation forces and the hydrodynamic drag are calculated numerically to handle particles of arbitrary shape, structure, and size. In this way, complex 3D particle translation and rotation inside experimental microdevices can be predicted. We simulate the rotation of a microfiber in an amplitude-modulated 2D field and analyze the results with respect to experimental observations. For a quantitative verification, the motion of an alumina microdisk is compared to a simple experiment. Demonstrating the potential of the simulation setup, we compute the trajectory of a red blood cell inside a realistic microdevice under the simultaneous effects of acoustic streaming and radiation forces. PMID:26448531

  18. Low-dose ionizing radiation induces mitochondrial fusion and increases expression of mitochondrial complexes I and III in hippocampal neurons

    PubMed Central

    Chang, Chuang-Rung; Kao, Mou-Chieh; Chen, Kuan-Wei; Chiu, Shih-Che; Hsu, Ming-Ling; Hsiang, I-Chou; Chen, Yu-Jen; Chen, Linyi

    2015-01-01

    High energy ionizing radiation can cause DNA damage and cell death. During clinical radiation therapy, the radiation dose could range from 15 to 60 Gy depending on targets. While 2 Gy radiation has been shown to cause cancer cell death, studies also suggest a protective potential by low dose radiation. In this study, we examined the effect of 0.2-2 Gy radiation on hippocampal neurons. Low dose 0.2 Gy radiation treatment increased the levels of MTT. Since hippocampal neurons are post-mitotic, this result reveals a possibility that 0.2 Gy irradiation may increase mitochondrial activity to cope with stimuli. Maintaining neural plasticity is an energy-demanding process that requires high efficient mitochondrial function. We thus hypothesized that low dose radiation may regulate mitochondrial dynamics and function to ensure survival of neurons. Our results showed that five days after 0.2 Gy irradiation, no obvious changes on neuronal survival, neuronal synapses, membrane potential of mitochondria, reactive oxygen species levels, and mitochondrial DNA copy numbers. Interestingly, 0.2 Gy irradiation promoted the mitochondria fusion, resulting in part from the increased level of a mitochondrial fusion protein, Mfn2, and inhibition of Drp1 fission protein trafficking to the mitochondria. Accompanying with the increased mitochondrial fusion, the expressions of complexes I and III of the electron transport chain were also increased. These findings suggest that, hippocampal neurons undergo increased mitochondrial fusion to modulate cellular activity as an adaptive mechanism in response to low dose radiation. PMID:26415228

  19. Reducing the Cognitive Complexity Associated with Standard Setting: A Comparison of the Single-Passage Bookmark and Yes/No Methods

    ERIC Educational Resources Information Center

    Skaggs, Gary; Hein, Serge F.

    2011-01-01

    Judgmental standard setting methods have been criticized for the cognitive complexity of the judgment task that panelists are asked to complete. This study compared two methods designed to reduce this complexity: the yes/no method and the single-passage bookmark method. Two mock standard setting panel meetings were convened, one for each method,…

  20. An EGS4 based mathematical phantom for radiation protection calculations using standard man

    SciTech Connect

    Wise, K.N.

    1994-11-01

    This note describes an Electron Gamma Shower code (EGS4) Monte Carlo program for calculating radiation transport in adult males and females from internal or external electron and gamma sources which requires minimal knowledge of organ geometry. Calculations of the dose from planar gamma fields and from computerized tomography illustrate two applications of the package. 25 refs., 5 figs.

  1. Natural element method for solving radiative transfer with or without conduction in three-dimensional complex geometries

    NASA Astrophysics Data System (ADS)

    Zhang, Yong; Ma, Yu; Yi, Hong-Liang; Tan, He-Ping

    2013-11-01

    A meshless method called as the natural element method (NEM) is developed for solving radiative heat transfer problem in 3D complex enclosures filled with an absorbing, emitting and scattering medium. The boundary surfaces are supposed to be opaque, diffuse as well as gray. The shape functions used in NEM are constructed by the natural neighbor interpolations, which are strictly interpolant and the essential boundary conditions can be imposed directly. The NEM solutions dealing with the radiative heat transfer with or without conduction are validated by comparison with some cases reported by the literature. Furthermore, the radiative heat transfer in cubic enclosures with or without an inner hollow sphere, cylinder and elliptical cylinder is also examined to demonstrate the applicability of the present method towards various three-dimensional geometries. For pure radiative transfer, both the cases of radiative non-equilibrium and radiative equilibrium are investigated. For combined conduction and radiation heat transfer, effects of various parameters such as the conduction-radiation parameter, the scattering albedo, the extinction coefficient, and the boundary emissivity are analyzed on the temperature distributions.

  2. The JCMT Gould Belt Survey: evidence for radiative heating and contamination in the W40 complex

    NASA Astrophysics Data System (ADS)

    Rumble, D.; Hatchell, J.; Pattle, K.; Kirk, H.; Wilson, T.; Buckle, J.; Berry, D. S.; Broekhoven-Fiene, H.; Currie, M. J.; Fich, M.; Jenness, T.; Johnstone, D.; Mottram, J. C.; Nutter, D.; Pineda, J. E.; Quinn, C.; Salji, C.; Tisi, S.; Walker-Smith, S.; Francesco, J. Di; Hogerheijde, M. R.; Ward-Thompson, D.; Bastien, P.; Bresnahan, D.; Butner, H.; Chen, M.; Chrysostomou, A.; Coude, S.; Davis, C. J.; Drabek-Maunder, E.; Duarte-Cabral, A.; Fiege, J.; Friberg, P.; Friesen, R.; Fuller, G. A.; Graves, S.; Greaves, J.; Gregson, J.; Holland, W.; Joncas, G.; Kirk, J. M.; Knee, L. B. G.; Mairs, S.; Marsh, K.; Matthews, B. C.; Moriarty-Schieven, G.; Mowat, C.; Rawlings, J.; Richer, J.; Robertson, D.; Rosolowsky, E.; Sadavoy, S.; Thomas, H.; Tothill, N.; Viti, S.; White, G. J.; Wouterloot, J.; Yates, J.; Zhu, M.

    2016-08-01

    We present SCUBA-2 450{\\mu}m and 850{\\mu}m observations of the W40 complex in the Serpens-Aquila region as part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Survey (GBS) of nearby star-forming regions. We investigate radiative heating by constructing temperature maps from the ratio of SCUBA-2 fluxes using a fixed dust opacity spectral index, {\\beta} = 1.8, and a beam convolution kernel to achieve a common 14.8" resolution. We identify 82 clumps ranging between 10 and 36K with a mean temperature of 20{\\pm}3K. Clump temperature is strongly correlated with proximity to the external OB association and there is no evidence that the embedded protostars significantly heat the dust. We identify 31 clumps that have cores with densities greater than 105cm{^{-3}}. Thirteen of these cores contain embedded Class 0/I protostars. Many cores are associated with bright-rimmed clouds seen in Herschel 70 {\\mu}m images. From JCMT HARP observations of the 12CO 3-2 line, we find contamination of the 850{\\mu}m band of up to 20 per cent. We investigate the free-free contribution to SCUBA-2 bands from large-scale and ultracompact H ii regions using archival VLA data and find the contribution is limited to individual stars, accounting for 9 per cent of flux per beam at 450 {\\mu}m or 12 per cent at 850 {\\mu}m in these cases. We conclude that radiative heating has potentially influenced the formation of stars in the Dust Arc sub-region, favouring Jeans stable clouds in the warm east and fragmentation in the cool west.

  3. The JCMT Gould Belt Survey: evidence for radiative heating and contamination in the W40 complex

    NASA Astrophysics Data System (ADS)

    Rumble, D.; Hatchell, J.; Pattle, K.; Kirk, H.; Wilson, T.; Buckle, J.; Berry, D. S.; Broekhoven-Fiene, H.; Currie, M. J.; Fich, M.; Jenness, T.; Johnstone, D.; Mottram, J. C.; Nutter, D.; Pineda, J. E.; Quinn, C.; Salji, C.; Tisi, S.; Walker-Smith, S.; Francesco, J. Di; Hogerheijde, M. R.; Ward-Thompson, D.; Bastien, P.; Bresnahan, D.; Butner, H.; Chen, M.; Chrysostomou, A.; Coude, S.; Davis, C. J.; Drabek-Maunder, E.; Duarte-Cabral, A.; Fiege, J.; Friberg, P.; Friesen, R.; Fuller, G. A.; Graves, S.; Greaves, J.; Gregson, J.; Holland, W.; Joncas, G.; Kirk, J. M.; Knee, L. B. G.; Mairs, S.; Marsh, K.; Matthews, B. C.; Moriarty-Schieven, G.; Mowat, C.; Rawlings, J.; Richer, J.; Robertson, D.; Rosolowsky, E.; Sadavoy, S.; Thomas, H.; Tothill, N.; Viti, S.; White, G. J.; Wouterloot, J.; Yates, J.; Zhu, M.

    2016-08-01

    We present SCUBA-2 450 μm and 850 μm observations of the W40 complex in the Serpens-Aquila region as part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Survey (GBS) of nearby star-forming regions. We investigate radiative heating by constructing temperature maps from the ratio of SCUBA-2 fluxes using a fixed dust opacity spectral index, β = 1.8, and a beam convolution kernel to achieve a common 14.8 arcsec resolution. We identify 82 clumps ranging between 10 and 36 K with a mean temperature of 20 ± 3 K. Clump temperature is strongly correlated with proximity to the external OB association and there is no evidence that the embedded protostars significantly heat the dust. We identify 31 clumps that have cores with densities greater than 105cm-3. 13 of these cores contain embedded Class 0/I protostars. Many cores are associated with bright-rimmed clouds seen in Herschel 70 μm images. From JCMT HARP observations of the 12CO 3-2 line, we find contamination of the 850 μm band of up to 20 per cent. We investigate the free-free contribution to SCUBA-2 bands from large-scale and ultracompact H II regions using archival VLA data and find the contribution is limited to individual stars, accounting for 9 per cent of flux per beam at 450 μm or 12 per cent at 850 μm in these cases. We conclude that radiative heating has potentially influenced the formation of stars in the Dust Arc sub-region, favouring Jeans stable clouds in the warm east and fragmentation in the cool west.

  4. Satellite-based solar radiation mapping over complex terrain: Validation in the Alps and possible improvements

    NASA Astrophysics Data System (ADS)

    Castelli, Mariapina; Stoeckli, Reto; Tetzlaff, Anke; Ernst Wagner, Jochen; Zardi, Dino; Petitta, Marcello

    2013-04-01

    . Consequently it is recommended to include in the clear-sky model more accurate input than the currently used monthly climatologies of aerosol and the operational 1 day forecast of column water vapor amount from the ECMWF model ouptut. References [1] K. V. Khlopenkov And A. P. Trishchenko, "SPARC: New Cloud, Snow, and Cloud Shadow Detection Scheme for Historical 1-km AVHHR Data over Canada", Journal of Atmospheric and Oceanic Technology, 24, pp. 322-343, 2007. [2] R.W. Müller, C. Matsoukas, A. Gratzki, H.D. Behr, R. Hollmann. "The CM-SAF operational scheme for the satellite based retrieval of solar surface irradiance - A LUT based eigenvector hybrid approach", Remote Sensing of Environment, 113, pp.1012-1024, 2009. [3] R. Stöckli (in prep.). "Supplementing Heliosat for physically-based surface radiation retrieval in complex terrain."

  5. Clinical comparison of brachytherapy versus hypofractionated external beam radiation versus standard fractionation external beam radiation for non-melanomatous skin cancers

    PubMed Central

    Haseltine, Justin M; Parker, Matthew; Wernicke, A. Gabriella; Nori, Dattatreyudu; Wu, Xian

    2016-01-01

    Purpose Non-melanomatous skin cancer (NMSC) is the single most common cancer in the US. Radiation therapy is an excellent treatment alternative to surgery. High-dose-rate (HDR) brachytherapy and external beam radiotherapy (EBRT) are commonly used radiation treatment modalities but little data is published comparing these modalities. We present our institution's experience and outcomes with these therapeutic options. Material and methods From June 2005 to March 2013, 61 patients were treated with HDR brachytherapy (n = 9), hypofractionated EBRT (n = 30), or standard fractionation EBRT (n = 22) for NMSC. The primary outcome measure was local control at most remote follow-up and secondary outcome measures were overall survival, cosmetic outcome, and toxicity. Univariate analysis was performed to compare outcomes between treatment modalities. Kaplan-Meier analysis and log-rank test were used to compare overall survival. Results Median follow-up was 30 months. The most common histologies were BCC (47%) and SCC (44%); mean patient age was 83.3 years. Local control was 81% and 2-year actuarial overall survival was 89%. There was no statistical difference in local control or overall survival between treatment modalities. There was no statistical difference in cosmetic outcome or toxicity between treatment modalities, although five of six “poor” cosmetic outcomes and the only grade 3 toxic events were found in the standard fractionation EBRT group. Conclusions All modalities investigated represent effective treatments for NMSC and have good cosmetic outcomes and acceptable toxicity profiles. The finding of higher grade toxicity and a greater portion of patients experiencing toxicity among standard fractionation therapy is counter to expectations. There was no statistical significance to the finding and it is not likely to be meaningful. PMID:27504127

  6. Low-intensity laser radiation in complex treatment of inflammatory diseases of parodontium

    NASA Astrophysics Data System (ADS)

    Sokolova, Irina A.; Erina, Stanislava V.

    1995-04-01

    The problem of complex treatment of inflammatory disease of parodontium has become very acute and actual at the moment. The diseases of inflammatory nature are considered to be the most vital issues of the day. The state of the local immune system of oral cavity plays the most important role in the complicated mechanism of inflammatory process development in the tissues of parodontium. Recently physical factors have become predominant in the system of complex therapy of parodontitis. The application of low-intense laser radiation (LLR) is considered to be the most important and up-to-date method in the preventive dentistry. There were 60 patients of average damage rate suffering from chronic generalizing parodontitis at the age of 25 up to 55 under observation. The major goal of examination was to get the objective results of the following methods' application: parodontium index (Russel, 1956), hygiene index (Fyodorov, Volodkina, 1971), Bacterioscopy of dental-gingival pockets content, simple and broadened stomatoscopy (Kunin, 1970), SIgA level determination in mixed saliva (Manchini et all, 1965) and R-protein level in gingival blood (Kulberg, 1990). All the patients were split into 2 groups. The first group (30 patients) has undergone the laser therapy course while the second group of 30 patients couldn't get it (LLR). Despite the kind of therapy they have undergone, all the patients have got the local anti-inflammatory medicamental therapy. The results of clinical observations have proved the fact that laser therapy application makes it possible to shorten the course of treatment in 1.5 times. The shifts of oral cavity local resistance take place in case of chronic generalizing parodontitis. The direct immunostimulating effect could be observed as a result of LLR- therapy application. The close connection of both anti-inflammatory medicamental and LLR-therapy has proved the possibility of purposeful local immune status correction in case of parodontitis.

  7. Secondary standards laboratories for ionizing radiation calibrations: The national laboratory interests

    NASA Astrophysics Data System (ADS)

    Roberson, P. I.; Campbell, G. W.

    1984-11-01

    The national laboratories are probable candidates to serve as secondary standards laboratories for the federal sector. Representatives of the major Department of Energy laboratories were polled concerning attitudes toward a secondary laboratory structure. Generally, the need for secondary laboratories was recognized and the development of such a program was encouraged. The secondary laboratories should be reviewed and inspected by the National Bureau of Standards. They should offer all of the essential, and preferably additional, calibration services in the field of radiological health protection. The selection of secondary laboratories should be based on economic and geographic criteria and/or be voluntary.

  8. Investigation of vesicle-capsular plague antigen complex formation by elastic laser radiation scattering

    NASA Astrophysics Data System (ADS)

    Guseva, N. P.; Maximova, Irina S.; Romanov, Sergey V.; Shubochkin, L. P.; Tatarintsev, Sergey N.

    1991-05-01

    Recently a great deal of attention has been given to the investigation artificial lipid liposomes, due to their application as "containers" for directed transport of biologically active compounds into particular cells, organs and tissues for prophylaxis and therapy of infectious diseases. The use of traditional methods of liposome investigation, such as sedimentation, electrophoresis and chromatography is impeded by low liposome resistivity to different deformations. In conjunction with this, optical methods of laser light scattering are promising as they allow nondisturbing, precise and quick investigations. This paper describes the investigation of vesicle systems prepared from egg lecithin of Serva Corporation and their complexes with the capsular antigen of the plague microbe. The capsular antigen Fl was obtained from EV plague microbe grown at 37° C on Huttinger agar. Fl was isolated by gel-filtration on ASA-22 followed by freeze drying of the preparation. Angular dependences of polarized radiation scattering were measured for several liposome suspension samples in a saline solution before and after the interaction with the plague microbe capsular antigen. The aim of the investigation was to analyze the nature of mutual antigen arrangement in a liposome and to develop methods for measuring its inclusion percentage.

  9. Effects of X-Ray Radiation on Complex Visual Discrimination Learning and Social Recognition Memory in Rats

    PubMed Central

    Davis, Catherine M.; Roma, Peter G.; Armour, Elwood; Gooden, Virginia L.; Brady, Joseph V.; Weed, Michael R.; Hienz, Robert D.

    2014-01-01

    The present report describes an animal model for examining the effects of radiation on a range of neurocognitive functions in rodents that are similar to a number of basic human cognitive functions. Fourteen male Long-Evans rats were trained to perform an automated intra-dimensional set shifting task that consisted of their learning a basic discrimination between two stimulus shapes followed by more complex discrimination stages (e.g., a discrimination reversal, a compound discrimination, a compound reversal, a new shape discrimination, and an intra-dimensional stimulus discrimination reversal). One group of rats was exposed to head-only X-ray radiation (2.3 Gy at a dose rate of 1.9 Gy/min), while a second group received a sham-radiation exposure using the same anesthesia protocol. The irradiated group responded less, had elevated numbers of omitted trials, increased errors, and greater response latencies compared to the sham-irradiated control group. Additionally, social odor recognition memory was tested after radiation exposure by assessing the degree to which rats explored wooden beads impregnated with either their own odors or with the odors of novel, unfamiliar rats; however, no significant effects of radiation on social odor recognition memory were observed. These data suggest that rodent tasks assessing higher-level human cognitive domains are useful in examining the effects of radiation on the CNS, and may be applicable in approximating CNS risks from radiation exposure in clinical populations receiving whole brain irradiation. PMID:25099152

  10. Beryllium Sampling and Analysis Within the DOE Complex and Opportunities for Standardization

    SciTech Connect

    BRISSON, MICHAEL

    2005-01-25

    Since the U. S. Department of Energy (DOE) published the DOE Beryllium Rule (10 CFR 850) in 1999, DOE sites have been required to measure beryllium on air filters and wipes for worker protection and for release of materials from beryllium-controlled areas. Measurements in the nanogram range on a filter or wipe are typically required. Industrial hygiene laboratories have applied methods from various analytical compendia, and a number of issues have emerged with sampling and analysis practices. As a result, a committee of analytical chemists, industrial hygienists, and laboratory managers was formed in November 2003 to address the issues. The committee developed a baseline questionnaire and distributed it to DOE sites and other agencies in the U.S. and U.K. The results of the questionnaire are presented in this paper. These results confirmed that a wide variety of practices were in use in the areas of sampling, sample preparation, and analysis. Additionally, although these laboratories are generally accredited by the American Industrial Hygiene Association (AIHA), there are inconsistencies in performance among accredited labs. As a result, there are significant opportunities for development of standard methods that could improve consistency. The current availabilities and needs for standard methods are further discussed in a companion paper.

  11. History of the development of radiation protection standards for space activities

    SciTech Connect

    Sinclair, W.K.

    1997-04-30

    Initial recommendations for limitations on radiation exposures in space were made in 1970 by the Radiobiological Advisory Panel of the Committee on Space Medicine, National Academy of Sciences/National Research Council (NAS/NRC). Using a risk-based approach and taking into consideration a range of factors, the Panel recommended an overall career limit of 4 Sv. Because it was assumed that only small numbers of people would be involved, most of whom would be in excess of 30 y of age, the question of genetic effects did not appear to be of concern. On the basis of subsequent epidemiological findings, the values of the risk coefficients were increased. As a result of this and other considerations, NASA in the early 1980s asked the NCRP to re-examine both the risks and the philosophy for protecting astronauts. In undertaking this task, the NCRP decided to treat the radiation exposures of crew members and payload specialists as an occupational hazard and to evaluate their risks in terms of those to radiation workers and to workers in other industries. Noting that in the less safe but not the most hazardous occupations, workers had an average lifetime risk of mortality of about three percent, the NCRP concluded that a reasonable career limit for astronauts should be based on a lifetime absolute excess risk of mortality of three percent. Using this as a base, the NCRP recommended a career limit for 25 y olds of 1 Sv for females and 1.5 Sv for males. Since the risk decreases the older the age at which the exposures begin, the limits culminated with a career limit of 3 Sv for females and 4 Sv for males whose initial exposure occurred at age 55. These recommendations were based on an assumed nominal value of a lifetime risk of fatal cancers for all ages of about 2 {times} 10{sup -2} Sv{sup -1}.

  12. Viable dark matter via radiative symmetry breaking in a scalar singlet Higgs portal extension of the standard model.

    PubMed

    Steele, T G; Wang, Zhi-Wei; Contreras, D; Mann, R B

    2014-05-01

    We consider the generation of dark matter mass via radiative electroweak symmetry breaking in an extension of the conformal standard model containing a singlet scalar field with a Higgs portal interaction. Generating the mass from a sequential process of radiative electroweak symmetry breaking followed by a conventional Higgs mechanism can account for less than 35% of the cosmological dark matter abundance for dark matter mass M(s)>80 GeV. However, in a dynamical approach where both Higgs and scalar singlet masses are generated via radiative electroweak symmetry breaking, we obtain much higher levels of dark matter abundance. At one-loop level we find abundances of 10%-100% with 106 GeV80 GeV detection region of the next generation XENON experiment. PMID:24836235

  13. Development and Use of Engineering Standards for Computational Fluid Dynamics for Complex Aerospace Systems

    NASA Technical Reports Server (NTRS)

    Lee, Hyung B.; Ghia, Urmila; Bayyuk, Sami; Oberkampf, William L.; Roy, Christopher J.; Benek, John A.; Rumsey, Christopher L.; Powers, Joseph M.; Bush, Robert H.; Mani, Mortaza

    2016-01-01

    Computational fluid dynamics (CFD) and other advanced modeling and simulation (M&S) methods are increasingly relied on for predictive performance, reliability and safety of engineering systems. Analysts, designers, decision makers, and project managers, who must depend on simulation, need practical techniques and methods for assessing simulation credibility. The AIAA Guide for Verification and Validation of Computational Fluid Dynamics Simulations (AIAA G-077-1998 (2002)), originally published in 1998, was the first engineering standards document available to the engineering community for verification and validation (V&V) of simulations. Much progress has been made in these areas since 1998. The AIAA Committee on Standards for CFD is currently updating this Guide to incorporate in it the important developments that have taken place in V&V concepts, methods, and practices, particularly with regard to the broader context of predictive capability and uncertainty quantification (UQ) methods and approaches. This paper will provide an overview of the changes and extensions currently underway to update the AIAA Guide. Specifically, a framework for predictive capability will be described for incorporating a wide range of error and uncertainty sources identified during the modeling, verification, and validation processes, with the goal of estimating the total prediction uncertainty of the simulation. The Guide's goal is to provide a foundation for understanding and addressing major issues and concepts in predictive CFD. However, this Guide will not recommend specific approaches in these areas as the field is rapidly evolving. It is hoped that the guidelines provided in this paper, and explained in more detail in the Guide, will aid in the research, development, and use of CFD in engineering decision-making.

  14. Reducing the complexity of the CCSDS standard for image compression decreasing the DWT filter order

    NASA Astrophysics Data System (ADS)

    Ito, Leandro H.; Pinho, Marcelo S.

    2014-10-01

    The goal for this work is to evaluate the impact of utilizing shorter wavelet filters in the CCSDS standard for lossy and lossless image compression. Another constraint considered was the existence of symmetry in the filters. That approach was desired to maintain the symmetric extension compatibility of the filter banks. Even though this strategy works well for oat wavelets, it is not always the case for their integer approximations. The periodic extension was utilized whenever symmetric extension was not applicable. Even though the latter outperforms the former, for fair comparison the symmetric extension compatible integer-to-integer wavelet approximations were evaluated under both extensions. The evaluation methods adopted were bit rate (bpp), PSNR and the number of operations required by each wavelet transforms. All these results were compared against the ones obtained utilizing the standard CCSDS with 9/7 filter banks, for lossy and lossless compression. The tests were performed over tallies (512x512) of raw remote sensing images from CBERS-2B (China-Brazil Earth Resources Satellites) captured from its high resolution CCD camera. These images were cordially made available by INPE (National Institute for Space Research) in Brazil. For the CCSDS implementation, it was utilized the source code developed by Hongqiang Wang from the Electrical Department at Nebraska-Lincoln University, applying the appropriate changes on the wavelet transform. For lossy compression, the results have shown that the filter bank built from the Deslauriers-Dubuc scaling function, with respectively 2 and 4 vanishing moments on the synthesis and analysis banks, presented not only a reduction of 21% in the number of operations required, but also a performance on par with the 9/7 filter bank. In the lossless case, the biorthogonal Cohen-Daubechies-Feauveau with 2 vanishing moments presented a performance close to the 9/7 integer approximation of the CCSDS, with the number of operations

  15. Neuropsychological Outcome of Children Treated for Standard Risk Medulloblastoma in the PNET4 European Randomized Controlled Trial of Hyperfractionated Versus Standard Radiation Therapy and Maintenance Chemotherapy

    SciTech Connect

    Câmara-Costa, Hugo; Resch, Anika; Kieffer, Virginie; Lalande, Clémence; Poggi, Geraldina; Kennedy, Colin; Bull, Kim; Calaminus, Gabriele; Grill, Jacques; Doz, François; Rutkowski, Stefan; Massimino, Maura; Kortmann, Rolf-Dieter; Lannering, Birgitta; Dellatolas, Georges; Chevignard, Mathilde

    2015-08-01

    Purpose: In the European HIT-SIOP PNET4 randomized controlled trial, children with standard risk medulloblastoma were allocated to hyperfractionated radiation therapy (HFRT arm, including a partially focused boost) or standard radiation therapy (STRT arm), followed, in both arms, by maintenance chemotherapy. Event-free survival was similar in both arms. Previous work showed that the HFRT arm was associated with worse growth and better questionnaire-based executive function, especially in children <8 years of age at diagnosis. Therefore, the aim of this study was to compare performance-based cognitive outcomes between treatment arms. Methods and Materials: Neuropsychological data were collected prospectively in 137 patients. Using the Wechsler Intelligence Scales, Kaufman Assessment Battery for Children, and Raven's Progressive Matrices, we estimated full-scale intelligence quotient (FSIQ) and, when available, verbal IQ (VIQ), performance IQ (PIQ), working memory index (WMI), and processing speed index (PSI). Results: Among the 137 participants (HFRT arm n=71, STRT arm n=66, 63.5% males), mean (±SD) ages at diagnosis and assessment respectively were 9.3 (±3.2) years of age (40.8% < 8 years of age at diagnosis) and 14.6 (±4.3) years of age. Mean (±SD) FSIQ was 88 (±19), and mean intergroup difference was 3.88 (95% confidence interval: −2.66 to 10.42, P=.24). No significant differences were found in children >8 years of age at diagnosis. In children <8 years of age at diagnosis, a marginally significant trend toward higher VIQ was found in those treated in the HFRT arm; a similar trend was found for PSI but not for PIQ, WMI, or FSIQ (mean intergroup differences were: 12.02 for VIQ [95% CI: 2.37-21.67; P=.02]; 3.77 for PIQ [95% CI: −5.19 to 12.74; P>.10]; 5.20 for WMI [95% CI: −2.07 to 12.47; P>.10]; 10.90 for PSI [95% CI: −1.54 to 23.36; P=.08]; and 5.28 for FSIQ [95% CI: −4.23 to 14.79; P>.10]). Conclusions: HFRT was associated with marginally

  16. Polyethylene as a Radiation Shielding Standard in SimulatedCosmic-Ray Environments

    SciTech Connect

    Guetersloh, Stephen B.; Zeitlin, Cary; Heilbronn, Lawrence H.; Miller, Jack; Komiyama, Tatsudo; Fukumura, A.; Iwata, Y.; Murakami, T.; Bhattacharya M.

    2006-08-19

    Radiation risk management for human space missions dependson accurate modeling of high-energy heavy ion transport in matter. Theprocess of nuclear fragmentation can play a key role in reducing both thephysical dose and the biological effectiveness of the radiationencountered in deep space. Hydrogenous materials and light elements areexpected to be more effective shields against the deleterious effects ofGalactic Cosmic Rays (GCR) than aluminum, which is used in currentspacecraft hulls. NASA has chosen polyethylene, CH2, as the referencematerial for accelerator-based radiation testing of multi-functioncomposites that are currently being developed. A detailed discussion ofthe shielding properties of polyethylene under a variety of relevantexperimental conditions is presented, along with Monte Carlo simulationsof the experiments and other Monte Carlo calculations in which the entireGCR flux is simulated. The Monte Carlo results are compared to theaccelerator data and we assess the usefulness of 1 GeV/amu 56Fe as aproxy for GCR heavy ions. We conclude that additional accelerator-basedmeasurements with higher beam energies would be useful.

  17. Using Next Generation Science Standards (NGSS) Practices to Address Scientific Misunderstandings Around Complex Environmental Issues

    NASA Astrophysics Data System (ADS)

    Turrin, M.; Kenna, T. C.

    2014-12-01

    The new NGSS provide an important opportunity for scientists to develop curriculum that links the practice of science to research-based data in order to improve understanding in areas of science that are both complex and confusing. Our curriculum focuses in particular on the fate and transport of anthropogenic radionuclides. Radioactivity, both naturally occurring and anthropogenic, is highly debated and largely misunderstood, and for large sections of the population is a source of scientific misunderstanding. Developed as part of the international GEOTRACES project which focuses on identifying ocean processes and quantifying fluxes that control the distributions of selected trace elements and isotopes in the ocean, and on establishing the sensitivity of these distributions to changing environmental conditions, the curriculum topic fits nicely into the applied focus of NGSS with both environmental and topical relevance. Our curriculum design focuses on small group discussion driven by questions, yet unlike more traditional curriculum pieces these are not questions posed to the students, rather they are questions posed by the students to facilitate their deeper understanding. Our curriculum design challenges the traditional question/answer memorization approach to instruction as we strive to develop an educational approach that supports the practice of science as well as the NGSS Cross Cutting Concepts and the Science & Engineering Practices. Our goal is for students to develop a methodology they can employ when faced with a complex scientific issue. Through background readings and team discussions they identify what type of information is important for them to know and where to find a reliable source for that information. Framing their discovery around key questions such as "What type of radioactive decay are we dealing with?", "What is the potential half-life of the isotope?", and "What are the pathways of transport of radioactivity?" allows students to evaluate a

  18. Average radiation doses in a standard head examination for 250 CT systems

    SciTech Connect

    McCrohan, J.L.; Patterson, J.F.; Gagne, R.M.; Goldstein, H.A.

    1987-04-01

    Approximately 250 computed tomography (CT) systems were surveyed in a nationwide study to determine the average radiation dose resulting from a typical adult head procedure. The multiple scan average dose (MSAD) was selected as the dose descriptor. For the typical adult CT head procedure, the MSAD was generally within 2.2-6.8 rads (22-68 mGy). Variations in dose by a factor of two or more were often seen for a given manufacturer and model. These dose ranges indicate a potential to reduce dose by carefully selecting imaging techniques. Overall, variations in dose can result from differences in the user's choice of technique (desired image quality) or from actual differences in scanner performance (caused by differences in collimation, filtration, or geometry). To use CT appropriately, a facility should consider dose as well as image quality in selecting optimal techniques for typical modes of operation.

  19. Recommendations for using the standardized terminology of respiratory physiology in radiation research

    SciTech Connect

    Mueller-Klieser, W.; Thews, G.; Sutherland, R.M.; Vaupel, P.

    1983-11-01

    A succinct review of the terminology and of correlations between basic quantities in respiration physiology is given with special regard to oxygen as the gas of topical interest in radiation research and tumor pathophysiology. The role of the oxygen partial pressure gradient as the driving force of O/sub 2/ diffusion is emphasized. It is generally recommended that the O/sub 2/ partial pressure be considered when investigating oxygen diffusion and distribution problems. During those studies the physical boundary conditions, in particular the temperature, the barometric pressure, and the water vapor saturation, have to be considered and should be indicated. During equilibration of suspensions containing oxygen-consuming sites the impact of geometry and fluid agitation on the efficiency of gas exchange has to be taken into account. Reviews on solutions of diffusion equations, on numerical data for relevant constants to be considered, and on terminology and units in respiration physiology are included.

  20. SU-E-P-22: AAPM Task Group 263 Tackling Standardization of Nomenclature for Radiation Therapy

    SciTech Connect

    Matuszak, M; Feng, M; Moran, J; Xiao, Y; Mayo, C; Miller, R; Bosch, W; Popple, R; Marks, L; Wu, Q; Molineu, A; Martel, M; Yock, T; McNutt, T; Brown, N; Purdie, T; Yorke, E; Santanam, L; Gabriel, P; Michalski, J; and others

    2015-06-15

    Purpose: There is growing recognition of need for increased clarity and consistency in the nomenclatures used for body and organ structures, DVH metrics, toxicity, dose and volume units, etc. Standardization has multiple benefits; e.g. facilitating data collection for clinical trials, enabling the pooling of data between institutions, making transfers (i.e. hand-offs) between centers safer, and enabling vendors to define “default” settings. Towards this goal, the American Association of Physicists in Medicine (AAPM) formed a task group (TG263) in July of 2014, operating under the Work Group on Clinical Trials to develop consensus statements. Guiding principles derived from the investigation and example nomenclatures will be presented for public feedback. Methods: We formed a multi-institutional and multi-vendor collaborative group of 39 physicists, physicians and others involved in clinical use and electronic transfer of information. Members include individuals from IROC, NRG, IHE-RO, DICOM WG-7, ASTRO and EORTC groups with overlapping interests to maximize the quality of the consensus and increase the likelihood of adoption. Surveys of group and NRG members were used to define current nomenclatures and requirements. Technical requirements of vendor systems and the proposed DICOM standards were examined. Results: There is a marked degree of inter and intra institutional variation in current approaches, resulting from inter-vendor differences in capabilities, clinic specific conceptualizations and inconsistencies. Using a consensus approach, the group defined optimal formats for the naming of targets and normal structures. A formal objective assessment of 13 existing clinically-used software packages show that all had capabilities to accommodate these recommended nomenclatures. Conclusions: A multi-stakeholder effort is making significant steps forward in developing a standard nomenclature that will work across platforms. Our current working list includes > 550

  1. Impact of ASTM Standard E722 update on radiation damage metrics.

    SciTech Connect

    DePriest, Kendall Russell

    2014-06-01

    The impact of recent changes to the ASTM Standard E722 is investigated. The methodological changes in the production of the displacement kerma factors for silicon has significant impact for some energy regions of the 1-MeV(Si) equivalent fluence response function. When evaluating the integral over all neutrons energies in various spectra important to the SNL electronics testing community, the change in the response results in an increase in the total 1-MeV(Si) equivalent fluence of 2 7%. Response functions have been produced and are available for users of both the NuGET and MCNP codes.

  2. The diverse and complex roles of radiation on cancer treatment: therapeutic target and genome maintenance

    PubMed Central

    Baskar, Rajamanickam; Yap, Swee Peng; Chua, Kevin Lee Min; Itahana, Koji

    2012-01-01

    Cancer is a genetic disease, grows exponentially with the development of intrinsic and acquired treatment resistance. Past decade has witnessed a considerable progress towards the treatment and understanding of proposed hallmarks of cancer and together with advances in early detection and various treatment modalities. Radiation therapy is an integral part of cancer treatment armamentarium. In developed countries more than half of all cancer patients receive radiation therapy during their course of illness. Although radiation damages both cancer and normal cells, the goal of radiation therapy is to maximize the radiation dose to abnormal cancer cells while minimizing exposure to normal cells, which is adjacent to cancer cells or in the path of radiation. In recent years, life expectancy increases among cancer patients and this increase is due to the results of early diagnosis, screening efforts, improved treatments and with less late effects mostly secondary cancer development. Therefore, cancer survivorship issues have been gaining prominence in the area of radiation oncology research. Understanding the tradeoff between the expected decreases in normal tissue toxicity resulting from an improved radiation dose distribution to the targeted site is an increasingly pertinent, yet needed attention and research in the area of radiation oncology. In recent years, a number of potential molecular targets that involve either with radiation increased tumor cell killing or protecting normal cells have been identified. For clinical benefits, translating these findings to maximize the toxicity of radiation on tumor cells while safeguarding early or late normal cell toxicities using molecular targeted radioprotectors will be useful in radiation treatment. PMID:22860229

  3. Direct CP violation in radiative b decays in and beyond the standard model

    NASA Astrophysics Data System (ADS)

    Kiers, Ken; Soni, Amarjit; Wu, Guo-Hong

    2000-12-01

    We consider the partial rate asymmetry in the inclusive decay modes b-->sγ and b-->dγ, concentrating on non-standard models with new charged Higgs interactions. We find that the charged Higgs contribution to the asymmetry for b-->sγ is small in such models due to a universal cancellation mechanism. The asymmetry is therefore difficult to distinguish experimentally from the standard model (SM) value, which is also small. The cancellation mechanism is found to be rendered inoperative in supersymmetry due to the presence of chargino loops. Unlike b-->sγ, the rate asymmetry for b-->dγ in Higgs models can be quite different from its SM value, generally ranging from -20% to +20%. Specific model calculations are performed for the three-Higgs-doublet model and the ``top'' two-Higgs-doublet model to serve as illustrations. We also offer some suggestions that may be helpful to experimentalists in the detection of the inclusive mode b-->dγ.

  4. Ethylene vinyl acetate based radiation grafted hydrophilic matrices: Process parameter standardization, grafting kinetics and characterization

    NASA Astrophysics Data System (ADS)

    Chaudhari, C. V.; Mondal, R. K.; Dubey, K. A.; Grover, V.; Panicker, L.; Bhardwaj, Y. K.; Varshney, L.

    2016-08-01

    A transparent, elastomeric, grafted matrix for several potential applications was synthesized by single-step simultaneous radiation grafting of methacrylic acid onto ethylene vinyl acetate (EVA). CuSO4 was found to be the most suitable homo-polymerization inhibitor among different inhibitors tried. The grafting kinetics was found to be a strong function of dose rate (D) and monomer content (M) and an equation relating grafting rate Rg=Kg [M]1.13D0.23 was deduced. Crystallinity of the grafted matrices as assessed from XRD and DSC measurements indicated decrease in crystalline content with increase in grafting yield, suggesting crystalline domain of EVA get disrupted on grafting. Elastic modulus increased linearly with the increase in grafting yield, though elongation at break decreased precipitously from 900% to 30% at even ~9% grafting. Thermo-gravimetric analysis showed three step weight loss of the grafted EVA matrix. The grafting of MAA resulted in increase in surface energy mainly due to enhanced polar component.

  5. Variations in the radiation sensitivity of foodborne pathogens associated with complex ready-to-eat food products

    NASA Astrophysics Data System (ADS)

    Sommers, Christopher H.; Boyd, Glenn

    2006-07-01

    Foodborne illness outbreaks and product recalls are occasionally associated with ready-to-eat (RTE) sandwiches and other "heat and eat" multi-component RTE products. Ionizing radiation can inactivate foodborne pathogens on meat and poultry, fruits and vegetables, seafood, and RTE meat products. However, less data are available on the ability of low-dose ionizing radiation, doses under 5 kGy typically used for pasteurization purposes, to inactivate pathogenic bacteria on complex multi-component food products. In this study, the efficacy of ionizing radiation to inactivate Salmonella spp., Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, and Yersinia enterocolitica on RTE foods including a "frankfurter on a roll", a "beef cheeseburger on a bun" and a "vegetarian cheeseburger on a bun" was investigated. The average D-10 values, the radiation dose needed to inactivate 1 log 10 of pathogen, by bacterium species, were 0.61, 0.54, 0.47, 0.36 and 0.15 kGy for Salmonella spp., S. aureus, L. monocytogenes, E. coli O157:H7, and Y. enterocolitica, respectively when inoculated onto the three product types. These results indicate that irradiation may be an effective means for inactivating common foodborne pathogens including Salmonella spp, S. aureus, L. monocytogenes, E. coli O157:H7 and Y. enterocolitica in complex RTE food products such as 'heat and eat" sandwich products.

  6. COOMET regional comparison of national measurement standards of air kerma for 137Cs γ radiation at protection level

    NASA Astrophysics Data System (ADS)

    Büermann, L.; Oborin, A. V.; Milevsky, V. S.; Walwyn Salas, G.; Sukhishvili, S.; Ginga, I.; Ivanov, R.; Gudelis, A.; Gomola, I.

    2014-01-01

    Results are presented of the COOMET supplementary comparison of the national measurement standards for air kerma in 137Cs γ radiation at protection level (~10 mGy/h). Ten National Metrology Institutes from the COOMET organization and the International Atomic Energy Agency participated in this COOMET project no. 445. The PTB acted as pilot laboratory. Two of the participants, the SMU (Slovakia) and the NSC-'IM' (Ukraine) participated in the measurements but did not submit a valid report of results. The comparison reference value (CRV) was obtained as the mean result of the PTB and the VNIIM, both of which had previously taken part in the key comparison BIPM-RI(I)-K5. The degree of equivalence with the CRV was evaluated. The results were consistent within the relative standard uncertainties of the comparison ranging from 0.28% to 1.3% and deviated from the CRV by less than 1%. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  7. The Standard European Vector Architecture (SEVA): a coherent platform for the analysis and deployment of complex prokaryotic phenotypes.

    PubMed

    Silva-Rocha, Rafael; Martínez-García, Esteban; Calles, Belén; Chavarría, Max; Arce-Rodríguez, Alejandro; de Las Heras, Aitor; Páez-Espino, A David; Durante-Rodríguez, Gonzalo; Kim, Juhyun; Nikel, Pablo I; Platero, Raúl; de Lorenzo, Víctor

    2013-01-01

    The 'Standard European Vector Architecture' database (SEVA-DB, http://seva.cnb.csic.es) was conceived as a user-friendly, web-based resource and a material clone repository to assist in the choice of optimal plasmid vectors for de-constructing and re-constructing complex prokaryotic phenotypes. The SEVA-DB adopts simple design concepts that facilitate the swapping of functional modules and the extension of genome engineering options to microorganisms beyond typical laboratory strains. Under the SEVA standard, every DNA portion of the plasmid vectors is minimized, edited for flaws in their sequence and/or functionality, and endowed with physical connectivity through three inter-segment insulators that are flanked by fixed, rare restriction sites. Such a scaffold enables the exchangeability of multiple origins of replication and diverse antibiotic selection markers to shape a frame for their further combination with a large variety of cargo modules that can be used for varied end-applications. The core collection of constructs that are available at the SEVA-DB has been produced as a starting point for the further expansion of the formatted vector platform. We argue that adoption of the SEVA format can become a shortcut to fill the phenomenal gap between the existing power of DNA synthesis and the actual engineering of predictable and efficacious bacteria. PMID:23180763

  8. The Standard European Vector Architecture (SEVA): a coherent platform for the analysis and deployment of complex prokaryotic phenotypes

    PubMed Central

    Silva-Rocha, Rafael; Martínez-García, Esteban; Calles, Belén; Chavarría, Max; Arce-Rodríguez, Alejandro; de las Heras, Aitor; Páez-Espino, A. David; Durante-Rodríguez, Gonzalo; Kim, Juhyun; Nikel, Pablo I.; Platero, Raúl; de Lorenzo, Víctor

    2013-01-01

    The ‘Standard European Vector Architecture’ database (SEVA-DB, http://seva.cnb.csic.es) was conceived as a user-friendly, web-based resource and a material clone repository to assist in the choice of optimal plasmid vectors for de-constructing and re-constructing complex prokaryotic phenotypes. The SEVA-DB adopts simple design concepts that facilitate the swapping of functional modules and the extension of genome engineering options to microorganisms beyond typical laboratory strains. Under the SEVA standard, every DNA portion of the plasmid vectors is minimized, edited for flaws in their sequence and/or functionality, and endowed with physical connectivity through three inter-segment insulators that are flanked by fixed, rare restriction sites. Such a scaffold enables the exchangeability of multiple origins of replication and diverse antibiotic selection markers to shape a frame for their further combination with a large variety of cargo modules that can be used for varied end-applications. The core collection of constructs that are available at the SEVA-DB has been produced as a starting point for the further expansion of the formatted vector platform. We argue that adoption of the SEVA format can become a shortcut to fill the phenomenal gap between the existing power of DNA synthesis and the actual engineering of predictable and efficacious bacteria. PMID:23180763

  9. Quantification of Complex Polycyclic Aromatic Hydrocarbon Mixtures in Standard Reference Materials Using GC×GC/ToF-MS

    PubMed Central

    Manzano, Carlos; Hoh, Eunha; Massey Simonich, Staci L.

    2014-01-01

    This research is the first to quantify complex PAH mixtures in NIST SRMs using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC/ToF-MS), with and without extract cleanup, and reports previously unidentified PAH isomers in the NIST SRMs. We tested a novel, high orthogonality GC column combination (LC-50×NSP-35), as well as with a commonly used column combination (Rtx-5ms×Rxi-17) for the quantification of a complex mixture of 85 different PAHs, including parent (PAHs), alkyl- (MPAHs), nitro- (NPAHs), oxy- (OPAHs), thio- (SPAHs), bromo- (BrPAHs), and chloro-PAHs (ClPAHs) in extracts from two standard reference materials: NIST SRM1650b (diesel particulate matter), with cleanup and NIST SRM1975 (diesel particulate extract), with and without extract cleanup. The LC-50×NSP-35 column combination resulted in an average absolute percent difference of 33.8%, 62.2% and 30.8% compared to the NIST certified PAH concentrations for NIST SRM1650b, NIST SRM1975 with cleanup and NIST SRM1975 without cleanup, while the Rtx-5ms×Rxi-17 resulted in an absolute percent difference of 38.6%, 67.2% and 79.6% for NIST SRM1650b, NIST SRM1975 with cleanup and NIST SRM1975 without cleanup, respectively. This GC×GC/ToF-MS method increases the number of PAHs detected and quantified in complex environmental extracts using a single chromatographic run. Without clean-up, 7 additional compounds were detected and quantified in NIST SRM1975 using the LC-50×NSP-35 column combination. These results suggest that the use of the LC-50×NSP-35 column combination in GC×GC/ToF-MS not only results in better chromatographic resolution and greater orthogonality for the separation of complex PAH mixtures, but can also be used for the accurate quantification of complex PAH mixtures in environmental extracts without cleanup. PMID:23932031

  10. Theoretical and Experimental Studies of Radiation from Z-Pinch Complex Wire Arrays and Applications

    NASA Astrophysics Data System (ADS)

    Weller, Michael Eugene

    In the research area of high energy density plasmas an ever increasing goal is searching for higher efficient radiators, particularly in z-pinch plasmas, and their applications. This goal is a major focus of this dissertation and implements both theoretical and experimental tools in the process. The theoretical tools involve the Wire Ablation Dynamics Model (WADM) to infer z-pinch implosion characteristics and various non-local thermodynamic equilibrium (LTE) kinetic models to understand the radiative properties of plasmas, including a new model for L-shell Ag. The experimental tools includes an advanced set of diagnostics, in particular a newly developed time-gated hard x-ray spectrometer to gain an understanding as to how these plasmas radiate in time, particularly in the 0.7 - 4.4 A range. The experiments predominately took place on the 1.7 MA Zebra generator at the Nevada Terawatt Facility (NTF) at the University of Nevada, Reno (UNR). Traditional nested cylindrical wire arrays with mixed materials (brass and Al, Mo and Al) were tested to understand how the inner and outer arrays implode and radiate. Novel planar wire arrays, which have been shown to be very powerful radiation sources, arranged in single, double, and triple wire array configurations were tested with Mo and Ag materials, which have both been shown to be powerful radiators, and also mixed with Al to understand opacity effects and how a mixture of two different plasmas radiate. Radiation from the extreme ultraviolet (EUV) range has also been of recent interest due the substantial contribution into total radiation yields. Therefore EUV radiation of M-shell Cu was modeled and benchmarked with spheromak and laser-produced plasma data. Lastly, lasing gain from L-shell Ag is calculated as an application of the aforementioned model to evaluate whether lasing might be occurring in wire array z-pinches. In connection to creating a uniform plasma column to measure lasing lines, the split double planar wire

  11. SU-E-T-353: Decoding the Beam Complexity in Intensity-Modulated Radiation Therapy Plans

    SciTech Connect

    Du, W; Cho, S; Zhang, X; Hoffman, K; Kudchadker, R

    2014-06-01

    Purpose: Modern IMRT relies on computers to generate treatment plans of varied complexity. A highly complex treatment plan may use a large number of small and irregular beam apertures in order to achieve high dose conformity. However, excessive beam complexity can increase dosimetric uncertainty, prolong treatment time, and increase susceptibility to target or organ motion. In this study we sought to develop metrics to assess the complexity of IMRT beams and plans. Methods: Based the information of leaf positions and MU for each beam segment, we calculated the following beam complexity metrics: aperture area, shape irregularity, and beam modulation. Then these beam complexity metrics were averaged to obtain the corresponding plan complexity metrics, using the beam MUs as weighting factors. We evaluated and compared the beam and plan complexity scores for 65 IMRT plans from 3 sites (prostate, head and neck, and spine). We also studied how the plan complexity scores were affected by adjusting inverse planning parameters. Results: For prostate IMRT, the lateral beams had large MUs and smaller shape irregularity, while the anterior or posterior beams had larger modulation values. On average, the prostate IMRT plans had the smallest shape irregularity and beam modulation; the HN IMRT plans had the largest aperture area, shape irregularity, and beam modulation; and the spine stereotactic IMRT plans often had small aperture area, which may be associated with relatively large discrepancies between calculated and measures doses. The plan complexity increased as the number of optimization iterations and the number of beam segments increased and as the minimum segment area decreased. Conclusion: Complexity of IMRT beams and plans were quantified in terms of aperture area, shape irregularity and beam modulation. The complexity metrics varied among IMRT plans for different disease sites and were affected when the planning parameters were adjusted.

  12. Computing the complex : Dusty plasmas in the presence of magnetic fields and UV radiation

    NASA Astrophysics Data System (ADS)

    Land, V.

    2007-12-01

    About 90% of the visible universe is plasma. Interstellar clouds, stellar cores and atmospheres, the Solar wind, the Earth's ionosphere, polar lights, and lightning are all plasma; ionized gases, consisting of electrons, ions, and neutrals. Not only many industries, like the microchip and solar cell industry, but also future fusion power stations, rely heavily on the use of plasma. More and more, home appliances include plasma technologies, like compact fluorescent light sources, and plasma screens. Dust particles, which can disrupt plasma processes, enter these plasmas, through chemical reactions in the plasma, or through interactions between plasma and walls. For instance, during microchip fabrication, dust particles can destroy the tiny, nanometre-sized structures on the surface of these chips. On the other hand, dust particles orbiting Young Stellar Objects coagulate and form the seeds of planets. In order to understand fundamental processes, such as planet formation, or to optimize industrial plasma processes, a thorough description of dusty plasma is necessary. Dust particles immersed in plasma collect ions and electrons from the plasma and charge up electrically. Therefore, the presence of dust changes plasma, while at the same time many forces start acting on the dust. Therefore, the dust and plasma become coupled, making dusty plasma a very complex medium to describe, in which many length and time scales play a role, from the Debye length to the length of the electrodes, and from the inverse plasma frequencies to the dust transport times. Using a self-consistent fluid model, we simulate these multi-scale dusty plasmas in radio frequency discharges under micro-gravity. We show that moderate non-linear scattering of ions by the dust particles is the most important aspect in the calculation of the ion drag force. This force is also responsible for the formation of a dust-free 'void' in dusty plasma under micro-gravity, caused by ions moving from the centre of

  13. A rapid fish radiation associated with the last sea-level changes in southern Brazil: the silverside Odontesthes perugiae complex.

    PubMed Central

    Beheregaray, Luciano B; Sunnucks, Paul; Briscoe, David A

    2002-01-01

    Coastal freshwater fishes provide valuable models for studying the role of the last glaciations in promoting speciation. To date, the great majority of studies are of Northern Hemisphere taxa, and reflect the influence of vicariant events during, or prior to, the Pleistocene. Microsatellite markers and mitochondrial DNA sequences were used to investigate patterns of population divergence and evolutionary relationships in a freshwater group of silverside fishes (Odontesthes perugiae complex), endemic to the recently formed coastal plain of southern Brazil. Lacustrine morphotypes showed concordant patterns of genetic and morphological divergence consistent with the geographical history of the coastal plain. The results support the proposal of a silverside radiation chronologically shaped by the sea-level changes of the Pleistocene and Holocene. The radiating lineage comprises a minimum of three allopatric and two sympatric lacustrine species. Four species displayed extremely high levels of genetic variation and some of the most rapid speciation rates reported in fishes. These features were related to a marine-estuarine origin of the radiation. To the best of our knowledge, this study represents the first molecular phylogeographic survey of a coastal radiation in South America. PMID:11788038

  14. Validating the MYSTIC three-dimensional radiative transfer model with observations from the complex topography of Arizona's Meteor Crater

    NASA Astrophysics Data System (ADS)

    Mayer, B.; Hoch, S. W.; Whiteman, C. D.

    2010-05-01

    The MYSTIC three-dimensional Monte-Carlo radiative transfer model has been extended to simulate solar and thermal irradiances with a rigorous consideration of topography. Forward as well as backward Monte Carlo simulations are possible for arbitrarily oriented surfaces and we demonstrate that the backward Monte Carlo technique is superior to the forward method for applications involving topography, by greatly reducing the computational demands. MYSTIC is used to simulate the short- and longwave radiation fields during a clear day and night in and around Arizona's Meteor Crater, a bowl-shaped, 165-m-deep basin with a diameter of 1200 m. The simulations are made over a 4 by 4 km domain using a 10-m horizontal resolution digital elevation model and meteorological input data collected during the METCRAX (Meteor Crater Experiment) field experiment in 2006. Irradiance (or radiative flux) measurements at multiple locations inside the crater are then used to evaluate the simulations. MYSTIC is shown to realistically model the complex interactions between topography and the radiative field, resolving the effects of terrain shading, terrain exposure, and longwave surface emissions. The effects of surface temperature variations and of temperature stratification within the crater atmosphere on the near-surface longwave irradiance are then evaluated with additional simulations.

  15. Validating the MYSTIC three-dimensional radiative transfer model with observations from the complex topography of Arizona's Meteor Crater

    NASA Astrophysics Data System (ADS)

    Mayer, B.; Hoch, S. W.; Whiteman, C. D.

    2010-09-01

    The MYSTIC three-dimensional Monte-Carlo radiative transfer model has been extended to simulate solar and thermal irradiances with a rigorous consideration of topography. Forward as well as backward Monte Carlo simulations are possible for arbitrarily oriented surfaces and we demonstrate that the backward Monte Carlo technique is superior to the forward method for applications involving topography, by greatly reducing the computational demands. MYSTIC is used to simulate the short- and longwave radiation fields during a clear day and night in and around Arizona's Meteor Crater, a bowl-shaped, 165-m-deep basin with a diameter of 1200 m. The simulations are made over a 4 by 4 km2 domain using a 10-m horizontal resolution digital elevation model and meteorological input data collected during the METCRAX (Meteor Crater Experiment) field experiment in 2006. Irradiance (or radiative flux) measurements at multiple locations inside the crater are then used to evaluate the simulations. MYSTIC is shown to realistically model the complex interactions between topography and the radiative field, resolving the effects of terrain shading, terrain exposure, and longwave surface emissions. The effects of surface temperature variations and of temperature stratification within the crater atmosphere on the near-surface longwave irradiance are then evaluated with additional simulations.

  16. Study of high speed complex number algorithms. [for determining antenna for field radiation patterns

    NASA Technical Reports Server (NTRS)

    Heisler, R.

    1981-01-01

    A method of evaluating the radiation integral on the curved surface of a reflecting antenna is presented. A three dimensional Fourier transform approach is used to generate a two dimensional radiation cross-section along a planer cut at any angle phi through the far field pattern. Salient to the method is an algorithm for evaluating a subset of the total three dimensional discrete Fourier transform results. The subset elements are selectively evaluated to yield data along a geometric plane of constant. The algorithm is extremely efficient so that computation of the induced surface currents via the physical optics approximation dominates the computer time required to compute a radiation pattern. Application to paraboloid reflectors with off-focus feeds in presented, but the method is easily extended to offset antenna systems and reflectors of arbitrary shapes. Numerical results were computed for both gain and phase and are compared with other published work.

  17. Aspects of Radiation Budget, Subsurface Lateral Moisture Exchange, and Vegetation Function in Areas of Complex Topography.

    NASA Astrophysics Data System (ADS)

    Ivanov, V. Y.; Bras, R. L.; Istanbulluoglu, E.; Vivoni, E. R.

    2004-12-01

    There is evidence that topography strongly affects the state, function, and distribution of vegetation by controlling incoming solar radiation and lateral redistribution of soil moisture. However, numerical experiments studying the effects that a topography can have on vegetation have oversimplified the treatment of topography and/or the representation of vegetation. We investigate the control of topography on vegetation state and stress via detailed modeling of radiation and soil moisture budgets across the varied terrain of a watershed. A detailed vegetation-hydrology model parameterizes the processes of canopy radiative transfer and rainfall interception and couples the processes of infiltration and evapotranspiration to photosynthesis via moisture uptake through a root systems with varied profiles. The model is applied on a continuous basis to synthetic watersheds of topography dominated by either convex or concave hillslopes. The numerical analysis is carried out for several plant functional types and soils. Inferences from the spatially-distributed dynamics are used to examine topographic niches favorable to vegetation.

  18. The complex interactions between radiation induced non-targeted effects and cancer.

    PubMed

    Campa, Alessandro; Balduzzi, Maria; Dini, Valentina; Esposito, Giuseppe; Tabocchini, Maria Antonella

    2015-01-01

    Radiation induced non-targeted effects have been widely investigated in the last two decades for their potential impact on low dose radiation risk. In this paper we will give an overview of the most relevant aspects related to these effects, starting from the definition of the low dose scenarios. We will underline the role of radiation quality, both in terms of mechanisms of interaction with the biological matter and for the importance of charged particles as powerful tools for low dose effects investigation. We will focus on cell communication, representing a common feature of non-targeted effects, giving also an overview of cancer models that have explicitly considered such effects. PMID:24139968

  19. Importance of acetylacetone and 2,2'-bipyridyl ligands in radiation-chemical processes of complex compounds

    NASA Astrophysics Data System (ADS)

    Kalecińska, E.; Kaleciński, J.

    The study of radiation response of free ligands: acetylacetone and 2,2'-bipyridyl in frozen chloride-alcohol-water glasses allows us to identify the intermediates playing the significant role in radiation decomposition of the complexes. On the basis of absorption spectra of the intermediates it has been shown that both examined ligands are effective scavengers of electrons. In the case of acetylacetone the intermediate most probably acacOH (exhibiting absorption band with λ max at ca. 580 nm) is not sensitive for bleaching light and its concentration increases during the warming up (from 77 to 160 K) of the sample. In the case of 2,2'-bipyridyl two intermediates (high intensity narrow bands with λ max at ca. 385 and 370 nm) are formed depending on pH of the system. Their formation and interconversion have also been studied.

  20. Neurobehavioral radiation mitigation to standard brain cancer therapy regimens by Mn(III) n-butoxyethylpyridylporphyrin-based redox modifier.

    PubMed

    Weitzel, Douglas H; Tovmasyan, Artak; Ashcraft, Kathleen A; Boico, Alina; Birer, Samuel R; Roy Choudhury, Kingshuk; Herndon, James; Rodriguiz, Ramona M; Wetsel, William C; Peters, Katherine B; Spasojevic, Ivan; Batinic-Haberle, Ines; Dewhirst, Mark W

    2016-06-01

    Combinations of radiotherapy (RT) and chemotherapy have shown efficacy toward brain tumors. However, therapy-induced oxidative stress can damage normal brain tissue, resulting in both progressive neurocognitive loss and diminished quality of life. We have recently shown that MnTnBuOE-2-PyP(5+) (Mn(III)meso-tetrakis(N-n-butoxyethylpyridinium -2-yl)porphyrin) rescued RT-induced white matter damage in cranially-irradiated mice. Radiotherapy is not used in isolation for treatment of brain tumors; temozolomide is the standard-of-care for adult glioblastoma, whereas cisplatin is often used for treatment of pediatric brain tumors. Therefore, we evaluated the brain radiation mitigation ability of MnTnBuOE-2-PyP(5+) after either temozolomide or cisplatin was used singly or in combination with 10 Gy RT. MnTnBuOE-2-PyP(5+) accumulated in brains at low nanomolar levels. Histological and neurobehavioral testing showed a drastic decrease (1) of axon density in the corpus callosum and (2) rotorod and running wheel performance in the RT only treatment group, respectively. MnTnBuOE-2-PyP(5+) completely rescued this phenotype in irradiated animals. In the temozolomide groups, temozolomide/ RT treatment resulted in further decreased rotorod responses over RT alone. Again, MnTnBuOE-2-PyP(5+) treatment rescued the negative effects of both temozolomide ± RT on rotorod performance. While the cisplatin-treated groups did not give similar results as the temozolomide groups, inclusion of MnTnBuOE-2-PyP(5+) did not negatively affect rotorod performance. Additionally, MnTnBuOE-2-PyP(5+) sensitized glioblastomas to either RT ± temozolomide in flank tumor models. Mice treated with both MnTnBuOE-2-PyP(5+) and radio-/chemo-therapy herein demonstrated brain radiation mitigation. MnTnBuOE-2-PyP(5+) may well serve as a normal tissue radio-/chemo-mitigator adjuvant therapy to standard brain cancer treatment regimens. Environ. Mol. Mutagen. 57:372-381, 2016. © 2016 Wiley Periodicals, Inc

  1. Radiation

    NASA Video Gallery

    Outside the protective cocoon of Earth's atmosphere, the universe is full of harmful radiation. Astronauts who live and work in space are exposed not only to ultraviolet rays but also to space radi...

  2. Evaluation of the WIPP Project`s compliance with the EPA radiation protection standards for disposal of transuranic waste

    SciTech Connect

    Neill, R.H.; Chaturvedi, L.; Rucker, D.F.; Silva, M.K.; Walker, B.A.; Channell, J.K.; Clemo, T.M. |

    1998-03-01

    The US Environmental Protection Agency`s (EPA) proposed rule to certify that the Waste Isolation Pilot Plant (WIPP) meets compliance with the long-term radiation protection standards for geologic repositories (40CFR191 Subparts B and C), is one of the most significant milestones to date for the WIPP project in particular, and for the nuclear waste issue in general. The Environmental Evaluation Group (EEG) has provided an independent technical oversight for the WIPP project since 1978, and is responsible for many improvements in the location, design, and testing of various aspects of the project, including participation in the development of the EPA standards since the early 1980s. The EEG reviewed the development of documentation for assessing the WIPP`s compliance by the Sandia National Laboratories following the 1985 promulgation by EPA, and provided many written and verbal comments on various aspects of this effort, culminating in the overall review of the 1992 performance assessment. For the US Department of Energy`s (DOE) compliance certification application (CCA), the EEG provided detailed comments on the draft CCA in March, 1996, and additional comments through unpublished letters in 1997 (included as Appendices 8.1 and 8.2 in this report). Since the October 30, 1997, publication of the EPA`s proposed rule to certify WIPP, the EEG gave presentations on important issues to the EPA on December 10, 1997, and sent a December 31, 1997 letter with attachments to clarify those issues (Appendix 8.3). The EEG has raised a number of questions that may have an impact on compliance. In spite of the best efforts by the EEG, the EPA reaction to reviews and suggestions has been slow and apparently driven by legal considerations. This report discusses in detail the questions that have been raised about containment requirements. Also discussed are assurance requirements, groundwater protection, individual protection, and an evaluation of EPA`s responses to EEG`s comments.

  3. Radiation and scattering by thin-wire structures in the complex frequency domain. [electromagnetic theory for thin-wire antennas

    NASA Technical Reports Server (NTRS)

    Richmond, J. H.

    1974-01-01

    Piecewise-sinusoidal expansion functions and Galerkin's method are employed to formulate a solution for an arbitrary thin-wire configuration in a homogeneous conducting medium. The analysis is performed in the real or complex frequency domain. In antenna problems, the solution determines the current distribution, impedance, radiation efficiency, gain and far-field patterns. In scattering problems, the solution determines the absorption cross section, scattering cross section and the polarization scattering matrix. The electromagnetic theory is presented for thin wires and the forward-scattering theorem is developed for an arbitrary target in a homogeneous conducting medium.

  4. Radiation effects and annealing kinetics in crystalline silicates, phosphates and complex Nb-Ta-Ti oxides. FInal Report

    SciTech Connect

    Ewing, R.C.

    1987-08-10

    Interaction of heavy particles (alpha-recoil nuclei, fission fragments, implanted ions) with ceramics is complex because they have a wide range of structure types, complex compositions and chemical bonding is variable. Radiation damage can produce diverse results, but most commonly, crystalline periodic materials become either polycrystalline or aperiodic (metamict state). We studied the transition from crystalline to aperiodic state in natural materials that have been damaged by alpha recoil nuclei in the U and Th decay series and in synthetic, analogous structure types which have been amorphized by ion implantation. Transition from crystalline to aperiodic was followed by analysis of XRD, high resolution TEM, and EXAFS/XANE spectroscopy. Use of these techniques with increasing dose provided data on an increasing finer scale as the damage process progressed.

  5. [Complex pathogenetic treatment schemes of vascular dyscirculatory disorders in the remote period after exposure to low dose radiation].

    PubMed

    2013-01-01

    Complex studies including modern methods of investigation of structures and functions of nervous system: electroencephalograsphy (EEG), coherent analysis, neuropsychological study and methods of neuroimaging were performed in 517 participants in liquidation of consequences of the accident (LCA) at the Chernobyl NPP in 1986-1987. Dyscirculatory metabolic encephalopathy was revealed to be the main pathology with the etiological mechanism based on dyscirculatorhypoxic and metabolic disorders. Complexity of the revealed symptoms testified to an early organism aging in remote periods after exposure to low dose radiation. Pathogenetic schemes were developed for treatment of dyscirculatory encephalopathy in liquidators, which include drugs improving blood supply, antiaggregants, antioxidants and metabolites of the brains in various combinations. Taking into consideration that early appearance of vascular dyscirculatory disorders observed in liquidators is the sign of early aging of the organism, geroprotectors were added to treatment schemes. PMID:25507773

  6. [Complex pathogenetic treatment schemes of vascular dyscirculatory disorders in the remote period after exposure to low dose radiation].

    PubMed

    Holodova, N B; Zhavoronkova, L A; Ryzhov, B N

    2013-01-01

    Complex studies including modern methods of investigation of structures and functions of nervous system: electroencephalograsphy (EEG), coherent analysis, neuropsychological study and methods of neuroimaging were performed in 517 participants in liquidation of consequences of the accident (LCA) at the Chernobyl NPP in 1986-1987. Dyscirculatory metabolic encephalopathy was revealed to be the main pathology with the etiological mechanism based on dyscirculatorhypoxic and metabolic disorders. Complexity of the revealed symptoms testified to an early organism aging in remote periods after exposure to low dose radiation. Pathogenetic schemes were developed for treatment of dyscirculatory encephalopathy in liquidators, which include drugs improving blood supply, antiaggregants, antioxidants and metabolites of the brains in various combinations. Taking into consideration that early appearance of vascular dyscirculatory disorders observed in liquidators is the sign of early aging of the organism, geroprotectors were added to treatment schemes. PMID:25434175

  7. On the standard conjecture and the existence of a Chow-Lefschetz decomposition for complex projective varieties

    NASA Astrophysics Data System (ADS)

    Tankeev, S. G.

    2015-02-01

    We prove the Grothendieck standard conjecture B(X) of Lefschetz type on the algebraicity of the operators * and Λ of Hodge theory for a smooth complex projective variety X if at least one of the following conditions holds: X is a compactification of the Néron minimal model of an Abelian scheme of relative dimension 3 over an affine curve, and the generic scheme fibre of the Abelian scheme has reductions of multiplicative type at all infinite places; X is an irreducible holomorphic symplectic (hyperkähler) 4-dimensional variety that coincides with the Altman-Kleiman compactification of the relative Jacobian variety of a family C\\to P^2 of hyperelliptic curves of genus 2 with weak degenerations, and the canonical projection X\\to P^2 is a Lagrangian fibration. We also show that a Chow-Lefschetz decomposition exists for every smooth projective 3-dimensional variety X which has the structure of a 1-parameter non-isotrivial family of K3-surfaces (with degenerations) or a family of regular surfaces of arbitrary Kodaira dimension \\varkappa with strong degenerations.

  8. Quality of Survival and Growth in Children and Young Adults in the PNET4 European Controlled Trial of Hyperfractionated Versus Conventional Radiation Therapy for Standard-Risk Medulloblastoma

    SciTech Connect

    Kennedy, Colin; Bull, Kim; Chevignard, Mathilde; Culliford, David; Dörr, Helmuth G.; Doz, François; Kortmann, Rolf-Dieter; Lannering, Birgitta; Massimino, Maura; Navajas Gutiérrez, Aurora; Rutkowski, Stefan; Spoudeas, Helen A.; Calaminus, Gabriele

    2014-02-01

    Purpose: To compare quality of survival in “standard-risk” medulloblastoma after hyperfractionated radiation therapy of the central nervous system with that after standard radiation therapy, combined with a chemotherapy regimen common to both treatment arms, in the PNET4 randomised controlled trial. Methods and Materials: Participants in the PNET4 trial and their parents/caregivers in 7 participating anonymized countries completed standardized questionnaires in their own language on executive function, health status, behavior, health-related quality of life, and medical, educational, employment, and social information. Pre- and postoperative neurologic status and serial heights and weights were also recorded. Results: Data were provided by 151 of 244 eligible survivors (62%) at a median age at assessment of 15.2 years and median interval from diagnosis of 5.8 years. Compared with standard radiation therapy, hyperfractionated radiation therapy was associated with lower (ie, better) z-scores for executive function in all participants (mean intergroup difference 0.48 SDs, 95% confidence interval 0.16-0.81, P=.004), but health status, behavioral difficulties, and health-related quality of life z-scores were similar in the 2 treatment arms. Data on hearing impairment were equivocal. Hyperfractionated radiation therapy was also associated with greater decrement in height z-scores (mean intergroup difference 0.43 SDs, 95% confidence interval 0.10-0.76, P=.011). Conclusions: Hyperfractionated radiation therapy was associated with better executive function and worse growth but without accompanying change in health status, behavior, or quality of life.

  9. Conservation laws, radiative decay rates, and excited state localization in organometallic complexes with strong spin-orbit coupling.

    PubMed

    Powell, B J

    2015-01-01

    There is longstanding fundamental interest in 6-fold coordinated d(6) (t(2g)(6)) transition metal complexes such as [Ru(bpy)3](2+) and Ir(ppy)3, particularly their phosphorescence. This interest has increased with the growing realisation that many of these complexes have potential uses in applications including photovoltaics, imaging, sensing, and light-emitting diodes. In order to design new complexes with properties tailored for specific applications a detailed understanding of the low-energy excited states, particularly the lowest energy triplet state, T1, is required. Here we describe a model of pseudo-octahedral complexes based on a pseudo-angular momentum representation and show that the predictions of this model are in excellent agreement with experiment - even when the deviations from octahedral symmetry are large. This model gives a natural explanation of zero-field splitting of T1 and of the relative radiative rates of the three sublevels in terms of the conservation of time-reversal parity and total angular momentum modulo two. We show that the broad parameter regime consistent with the experimental data implies significant localization of the excited state. PMID:26123864

  10. Conservation laws, radiative decay rates, and excited state localization in organometallic complexes with strong spin-orbit coupling

    PubMed Central

    Powell, B. J.

    2015-01-01

    There is longstanding fundamental interest in 6-fold coordinated d6 () transition metal complexes such as [Ru(bpy)3]2+ and Ir(ppy)3, particularly their phosphorescence. This interest has increased with the growing realisation that many of these complexes have potential uses in applications including photovoltaics, imaging, sensing, and light-emitting diodes. In order to design new complexes with properties tailored for specific applications a detailed understanding of the low-energy excited states, particularly the lowest energy triplet state, T1, is required. Here we describe a model of pseudo-octahedral complexes based on a pseudo-angular momentum representation and show that the predictions of this model are in excellent agreement with experiment - even when the deviations from octahedral symmetry are large. This model gives a natural explanation of zero-field splitting of T1 and of the relative radiative rates of the three sublevels in terms of the conservation of time-reversal parity and total angular momentum modulo two. We show that the broad parameter regime consistent with the experimental data implies significant localization of the excited state. PMID:26123864

  11. On Influence of Neutrals on Dust Particle Charging in Complex Plasmas in the Presence of Electromagnetic Radiation

    SciTech Connect

    Kopnin, S. I.; Morzhakova, A. A.; Popel, S. I.; Shukla, P. K.

    2011-11-29

    Effects associated with neutral component of complex (dusty) ionospheric plasmas which affect dust particle charging are studied. Microscopic ion currents on dust particles with taking into account ion-neutral interaction are presented. Calculations are performed both for the case of negative charges of dust particles, when the influence of Solar radiation on dust particle charging processes is negligible, and for the case of positive charges which is realized in the presence of sufficiently intensive UV or X-ray radiation. We also carry out investigation of the electron heating due to the photoelectric effect. We show that the efficiency of electron heating depends on the density of neutral component of the plasma. As result, we determine altitudes where the influence of the neutral plasma component on dust particle charging processes as well as the electron heating effect are significant and should be taken into account under consideration of the ionospheric complex plasmas. In particular, we show that the effects considered could be important for the description of noctilucent clouds, polar mesosphere summer echoes, and some other physical phenomena associated with dust particles in the ionosphere.

  12. Context dependence in complex adaptive landscapes: frequency and trait-dependent selection surfaces within an adaptive radiation of Caribbean pupfishes.

    PubMed

    Martin, Christopher H

    2016-06-01

    The adaptive landscape provides the foundational bridge between micro- and macroevolution. One well-known caveat to this perspective is that fitness surfaces depend on ecological context, including competitor frequency, traits measured, and resource abundance. However, this view is based largely on intraspecific studies. It is still unknown how context-dependence affects the larger features of peaks and valleys on the landscape which ultimately drive speciation and adaptive radiation. Here, I explore this question using one of the most complex fitness landscapes measured in the wild in a sympatric pupfish radiation endemic to San Salvador Island, Bahamas by tracking survival and growth of laboratory-reared F2 hybrids. I present new analyses of the effects of competitor frequency, dietary isotopes, and trait subsets on this fitness landscape. Contrary to expectations, decreasing competitor frequency increased survival only among very common phenotypes, whereas less common phenotypes rarely survived despite few competitors, suggesting that performance, not competitor frequency, shapes large-scale features of the fitness landscape. Dietary isotopes were weakly correlated with phenotype and growth, but did not explain additional survival variation. Nonlinear fitness surfaces varied substantially among trait subsets, revealing one-, two-, and three-peak landscapes, demonstrating the complexity of selection in the wild, even among similar functional traits. PMID:27130447

  13. Complex radiation-thermal history of Kaidun meteorite on data of track study of silicate minerals

    NASA Technical Reports Server (NTRS)

    Kashkarov, L. L.; Korotkova, N. N.; Skripnik, A. YA.

    1993-01-01

    The results of track study of approximately 80 individual silicate mineral crystals (ol, px, plag) picked out from Kaidun meteorite are presented. A wide range of observed rho(sub VH) value distributions indicate the complex irradiation history of Kaidun minerals. In one anortite crystal having two track groups with different parameters the pre-accretion irradiation traces were observed in all probability.

  14. Enhancement of cellular radiation sensitivity through degradation of Chk1 by the XIAP-XAF1 complex

    PubMed Central

    Kim, Kwang Seok; Heo, Jong-Ik; Choi, Kyu Jin; Bae, Sangwoo

    2014-01-01

    X-linked inhibitor of apoptosis (XIAP) and Chk1 are potential molecular targets in radiotherapy. However, their molecular association in the regulation of radiation sensitivity has been rarely studied. Here, we show that XIAP modulates radiation sensitivity by regulating stability of Chk1 in lung cancer cells. Both Chk1 and XIAP are highly expressed in various lung cancer cells. Overexpression of XIAP increased cell survival following genotoxic treatments by preventing downregulation of Chk1. However, XIAP reversed Chk1-protective activity in the presence of XIAP-associated factor 1 (XAF1) by degrading Chk1 via ubiquitination-dependent proteasomal proteolysis. The XIAP-XAF1 complex-mediated Chk1 degradation also required CUL4A and DDB1. Chk1 or XIAP was associated with DDB1 and CUL4A. Depletion of CUL4A or DDB1 prevented the XIAP-XAF1-mediated Chk1 degradation suggesting involvement of a CUL4A/DDB1-based E3 ubiquitin ligase in the process or its collaboration with XIAP E3 ligase activity. Taken together, our findings show that XIAP plays a dual role in modulation of Chk1 stability and cell viability following IR. In the absence of XAF1, XIAP stabilizes Chk1 under IR with corresponding increase of cell viability. By contrast, when XAF1 is overexpressed, XIAP facilitates Chk1 degradation, which leads to enhancement of radiation sensitivity. This selective regulation of Chk1 stability by XIAP and XAF1 could be harnessed to devise a strategy to modulate radiation sensitivity in lung cancer cells. PMID:25535897

  15. The analysis of complex mixed-radiation fields using near real-time imaging.

    PubMed

    Beaumont, Jonathan; Mellor, Matthew P; Joyce, Malcolm J

    2014-10-01

    A new mixed-field imaging system has been constructed at Lancaster University using the principles of collimation and back projection to passively locate and assess sources of neutron and gamma-ray radiation. The system was set up at the University of Manchester where three radiation sources: (252)Cf, a lead-shielded (241)Am/Be and a (22)Na source were imaged. Real-time discrimination was used to find the respective components of the neutron and gamma-ray fields detected by a single EJ-301 liquid scintillator, allowing separate images of neutron and gamma-ray emitters to be formed. (252)Cf and (22)Na were successfully observed and located in the gamma-ray image; however, the (241)Am/Be was not seen owing to surrounding lead shielding. The (252)Cf and (241)Am/Be neutron sources were seen clearly in the neutron image, demonstrating the advantage of this mixed-field technique over a gamma-ray-only image where the (241)Am/Be source would have gone undetected. PMID:24782559

  16. Euroforgen-NoE collaborative exercise on LRmix to demonstrate standardization of the interpretation of complex DNA profiles.

    PubMed

    Prieto, L; Haned, H; Mosquera, A; Crespillo, M; Alemañ, M; Aler, M; Alvarez, F; Baeza-Richer, C; Dominguez, A; Doutremepuich, C; Farfán, M J; Fenger-Grøn, M; García-Ganivet, J M; González-Moya, E; Hombreiro, L; Lareu, M V; Martínez-Jarreta, B; Merigioli, S; Milans Del Bosch, P; Morling, N; Muñoz-Nieto, M; Ortega-González, E; Pedrosa, S; Pérez, R; Solís, C; Yurrebaso, I; Gill, P

    2014-03-01

    There has been very little work published on the variation of reporting practices of mixtures between laboratories, but it has been previously demonstrated that there is little consistency. This is because there is no current uniformity of practice, so different laboratories will operate using different rules. The interpretation of mixtures is not solely a matter of using some software to provide 'an answer'. An assessment of a case will usually begin with a consideration of the circumstances of a crime. Assumptions made about the numbers of contributors follow from an examination of the electropherogram(s)--and these may differ between the prosecution and the defence hypotheses. There may be a necessity to evaluate several sets of hypotheses for any given case if the circumstances are uncertain. Once the hypotheses are formulated, the mathematical analysis is complex and can only be accomplished by the use of specialist software. In order to obtain meaningful results, it is essential that scientists are trained, not only in the use of the software, but also in the methodology to understand the likelihood ratio concept that is used. The Euroforgen-NoE initiative has developed a training course that utilizes the LRmix program to carry out the calculations. This software encompasses the recommendations of the ISFG DNA commissions on mixture interpretation and is able to interpret samples that may come from two or more contributors and may also be partial profiles. Recently, eighteen different laboratories were trained in the methodology. Afterwards they were asked to independently analyze two different cases with partial mixture DNA evidence and to write a statement court-report. We show that by introducing a structured training programme, it is possible to demonstrate, for the first time, that a high degree of standardization, leading to uniformity of results can be achieved by participating laboratories. PMID:24528579

  17. Chemical Partition of the Radiative Decay Rate of Luminescence of Europium Complexes

    NASA Astrophysics Data System (ADS)

    Lima, Nathalia B. D.; Dutra, José Diogo L.; Gonçalves, Simone M. C.; Freire, Ricardo O.; Simas, Alfredo M.

    2016-02-01

    The spontaneous emission coefficient, Arad, a global molecular property, is one of the most important quantities related to the luminescence of complexes of lanthanide ions. In this work, by suitable algebraic transformations of the matrices involved, we introduce a partition that allows us to compute, for the first time, the individual effects of each ligand on Arad, a property of the molecule as a whole. Such a chemical partition thus opens possibilities for the comprehension of the role of each of the ligands and their interactions on the luminescence of europium coordination compounds. As an example, we applied the chemical partition to the case of repeating non-ionic ligand ternary complexes of europium(III) with DBM, TTA, and BTFA, showing that it allowed us to correctly order, in an a priori manner, the non-obvious pair combinations of non-ionic ligands that led to mixed-ligand compounds with larger values of Arad.

  18. Chemical Partition of the Radiative Decay Rate of Luminescence of Europium Complexes

    PubMed Central

    Lima, Nathalia B. D.; Dutra, José Diogo L.; Gonçalves, Simone M. C.; Freire, Ricardo O.; Simas, Alfredo M.

    2016-01-01

    The spontaneous emission coefficient, Arad, a global molecular property, is one of the most important quantities related to the luminescence of complexes of lanthanide ions. In this work, by suitable algebraic transformations of the matrices involved, we introduce a partition that allows us to compute, for the first time, the individual effects of each ligand on Arad, a property of the molecule as a whole. Such a chemical partition thus opens possibilities for the comprehension of the role of each of the ligands and their interactions on the luminescence of europium coordination compounds. As an example, we applied the chemical partition to the case of repeating non-ionic ligand ternary complexes of europium(III) with DBM, TTA, and BTFA, showing that it allowed us to correctly order, in an a priori manner, the non-obvious pair combinations of non-ionic ligands that led to mixed-ligand compounds with larger values of Arad. PMID:26892900

  19. Large Eddy Simulation of complex sidearms subject to solar radiation and surface cooling.

    PubMed

    Dittko, Karl A; Kirkpatrick, Michael P; Armfield, Steven W

    2013-09-15

    Large Eddy Simulation (LES) is used to model two lake sidearms subject to heating from solar radiation and cooling from a surface flux. The sidearms are part of Lake Audrey, NJ, USA and Lake Alexandrina, SA, Australia. The simulation domains are created using bathymetry data and the boundary is modelled with an Immersed Boundary Method. We investigate the cooling and heating phases with separate quasi-steady state simulations. Differential heating occurs in the cavity due to the changing depth. The resulting temperature gradients drive lateral flows. These flows are the dominant transport process in the absence of wind. Study in this area is important in water quality management as the lateral circulation can carry particles and various pollutants, transporting them to and mixing them with the main lake body. PMID:23863384

  20. Probing Ionic Complexes of Ethylene and Acetylene with Vacuum-Ultraviolet Radiation.

    PubMed

    Bandyopadhyay, Biswajit; Stein, Tamar; Fang, Yigang; Kostko, Oleg; White, Alec; Head-Gordon, Martin; Ahmed, Musahid

    2016-07-14

    Mixed complexes of acetylene-ethylene are studied using vacuum-ultraviolet (VUV) photoionization mass spectrometry and theoretical calculations. These complexes are produced and ionized at different distances from the exit of a continuous nozzle followed by reflectron time-of-flight mass spectrometry detection. Acetylene, with a higher ionization energy (11.4 eV) than ethylene (10.6 eV), allows for tuning the VUV energy and initializing reactions either from a C2H2(+) or a C2H4(+) cation. Pure acetylene and ethylene expansions are separately carried out to compare, contrast, and hence identify products from the mixed expansion: these are C3H3(+) (m/z = 39), C4H5(+) (m/z = 53), and C5H5(+) (m/z = 65). Intensity distributions of C2H2, C2H4, their dimers and reactions products are plotted as a function of ionization distance. These distributions suggest that association mechanisms play a crucial role in product formation closer to the nozzle. Photoionization efficiency (PIE) curves of the mixed complexes demonstrate rising edges closer to both ethylene and acetylene ionization energies. We use density functional theory (ωB97X-V/aug-cc-pVTZ) to study the structures of the neutral and ionized dimers, calculate their adiabatic and vertical ionization energies, as well as the energetics of different isomers on the potential energy surface (PES). Upon ionization, vibrationally excited clusters can use the extra energy to access different isomers on the PES. At farther ionization distances from the nozzle, where the number densities are lower, unimolecular decay is expected to be the dominant mechanism. We discuss the possible decay pathways from the different isomers on the PES and examine the ones that are energetically accessible. PMID:26983013

  1. Scattering and radiative properties of complex soot and soot-containing particles

    NASA Astrophysics Data System (ADS)

    Liu, L.; Mishchenko, M. I.; Mackowski, D. W.; Dlugach, J.

    2012-12-01

    Tropospheric soot and soot containing aerosols often exhibit nonspherical overall shapes and complex morphologies. They can externally, semi-externally, and internally mix with other aerosol species. This poses a tremendous challenge in particle characterization, remote sensing, and global climate modeling studies. To address these challenges, we used the new numerically exact public-domain Fortran-90 code based on the superposition T-matrix method (STMM) and other theoretical models to analyze the potential effects of aggregation and heterogeneity on light scattering and absorption by morphologically complex soot containing particles. The parameters we computed include the whole scattering matrix elements, linear depolarization ratios, optical cross-sections, asymmetry parameters, and single scattering albedos. It is shown that the optical characteristics of soot and soot containing aerosols very much depend on particle sizes, compositions, and aerosol overall shapes. The soot particle configurations and heterogeneities can have a substantial effect that can result in a significant enhancement of extinction and absorption relative to those computed from the Lorenz-Mie theory. Meanwhile the model calculated information combined with in-situ and remote sensed data can be used to constrain soot particle shapes and sizes which are much needed in climate models.

  2. Hawking radiation for twisted complex scalar fields on the Reissner-Nordström black holes and Dirac monopoles

    NASA Astrophysics Data System (ADS)

    Goncharov, Yu. P.; Firsova, N. E.

    1997-02-01

    We study, both analytically and numerically, the contribution of the twisted topologically inequivalent configurations (TICs) of complex scalar fields on the Reissner-Nordström black holes to the Hawking radiation. Physically this contribution is conditioned by the natural presence of the Dirac monopoles on the black holes. When neglecting the own (external) electric field of black hole it is established that while increasing the black hole electric charge Q to the extremal value Q = M (M is the black hole mass), the given contribution to the total luminosity (summed up over all the TICs) of the black hole decreases (from the one of order 17% at Q = 0) up to 0. At this value the total luminosity itself tends to 0.

  3. A Manganese–Porphyrin Complex Decomposes H2O2, Inhibits Apoptosis, and Acts as a Radiation Mitigator in Vivo

    PubMed Central

    2011-01-01

    Ionizing radiation triggers mitochondrial overproduction of H2O2 with concomitant induction of intrinsic apoptosis, whereby clearance of H2O2 upon overexpression of mitochondrial catalase increases radioresistance in vitro and in vivo. As an alternative to gene therapy, we tested the potential of Mn(III)–porphyrin complexes to clear mitochondrial H2O2. We report that triphenyl-[(2E)-2-[4-[(1Z,4Z,9Z,15Z)-10,15,20-tris(4-aminophenyl)-21,23-dihydroporphyrin-5-yl]phenyl]iminoethyl]phosphonium-Mn(III) compartmentalizes preferentially into mitochondria of mouse embryonic cells, reacts with H2O2, impedes γ-ray-induced mitochondrial apoptosis, and increases the survival of mice exposed to whole body irradiation with γ-rays. PMID:22247787

  4. A manganese-porphyrin complex decomposes H(2)O(2), inhibits apoptosis, and acts as a radiation mitigator in vivo.

    PubMed

    Stoyanovsky, Detcho A; Huang, Zhentai; Jiang, Jianfei; Belikova, Natalia A; Tyurin, Vladimir; Epperly, Michael W; Greenberger, Joel S; Bayir, Hülya; Kagan, Valerian E

    2011-11-10

    Ionizing radiation triggers mitochondrial overproduction of H(2)O(2) with concomitant induction of intrinsic apoptosis, whereby clearance of H(2)O(2) upon overexpression of mitochondrial catalase increases radioresistance in vitro and in vivo. As an alternative to gene therapy, we tested the potential of Mn((III))-porphyrin complexes to clear mitochondrial H(2)O(2). We report that triphenyl-[(2E)-2-[4-[(1Z,4Z,9Z,15Z)-10,15,20-tris(4-aminophenyl)-21,23-dihydroporphyrin-5-yl]phenyl]iminoethyl]phosphonium-Mn((III)) compartmentalizes preferentially into mitochondria of mouse embryonic cells, reacts with H(2)O(2), impedes γ-ray-induced mitochondrial apoptosis, and increases the survival of mice exposed to whole body irradiation with γ-rays. PMID:22247787

  5. Complex Responses of Intertidal Molluscan Embryos to a Warming and Acidifying Ocean in the Presence of UV Radiation

    PubMed Central

    Davis, Andrew R.; Coleman, Daniel; Broad, Allison; Byrne, Maria; Dworjanyn, Symon A.; Przeslawski, Rachel

    2013-01-01

    Climate change and ocean acidification will expose marine organisms to synchronous multiple stressors, with early life stages being potentially most vulnerable to changing environmental conditions. We simultaneously exposed encapsulated molluscan embryos to three abiotic stressors—acidified conditions, elevated temperate, and solar UV radiation in large outdoor water tables in a multifactorial design. Solar UV radiation was modified with plastic filters, while levels of the other factors reflected IPCC predictions for near-future change. We quantified mortality and the rate of embryonic development for a mid-shore littorinid, Bembicium nanum, and low-shore opisthobranch, Dolabrifera brazieri. Outcomes were consistent for these model species with embryos faring significantly better at 26°C than 22°C. Mortality sharply increased at the lowest temperature (22°C) and lowest pH (7.6) examined, producing a significant interaction. Under these conditions mortality approached 100% for each species, representing a 2- to 4-fold increase in mortality relative to warm (26°C) non-acidified conditions. Predictably, development was more rapid at the highest temperature but this again interacted with acidified conditions. Development was slowed under acidified conditions at the lowest temperature. The presence of UV radiation had minimal impact on the outcomes, only slowing development for the littorinid and not interacting with the other factors. Our findings suggest that a warming ocean, at least to a threshold, may compensate for the effects of decreasing pH for some species. It also appears that stressors will interact in complex and unpredictable ways in a changing climate. PMID:23405238

  6. Complex composite engineering architectures for nuclear and high-radiation environments

    SciTech Connect

    Kornreich, Drew E; Vaidya, Rajendra U; Ammerman, Curtt N

    2010-01-01

    Integrated Computational Materials Engineering (ICME) is a novel overarching approach to bridge length and time scales in computational materials science and engineering. This approach integrates all elements of multi-scale modeling (including various empirical and science-based models) with materials informatics to provide users the opportunity to tailor material selections based on stringent application needs. Typically, materials engineering has focused on structural requirements (stress, strain, modulus, fracture toughness etc.) while multi-scale modeling has been science focused (mechanical threshold strength model, grain-size models, solid-solution strengthening models etc.). Materials informatics (mechanical property inventories) on the other hand, is extensively data focused. All of these elements are combined within the framework of ICME to create architecture for the development, selection and design new composite materials for challenging environments. We propose development of the foundations for applying ICME to composite materials development for nuclear and high-radiation environments (including nuclear-fusion energy reactors, nuclear-fission reactors, and accelerators). We expect to combine all elements of current material models (including thermo-mechanical and finite-element models) into the ICME framework. This will be accomplished through the use of a various mathematical modeling constructs. These constructs will allow the integration of constituent models, which in tum would allow us to use the adaptive strengths of using a combinatorial scheme (fabrication and computational) for creating new composite materials. A sample problem where these concepts are used is provided in this summary.

  7. The normalised difference vegetation index obtained from agrometeorological standard radiation sensors: A comparison with ground-based multiband spectroradiometer measurements during the phenological development of an oat canopy.

    PubMed

    Wittich, Klaus-Peter; Kraft, Martin

    2008-01-01

    Following the methodology of K. F. Huemmrich and colleagues [Huemmrich et al. (1999) J Geophys Res 104:27,935-27,944], agrometeorological standard radiation sensors, i.e. two photosynthetically active radiation sensors and an albedometer, were used to measure the broadband visible and optical-infrared reflectance of an oat plot during its whole growth period. From these reflectance data - recorded as 15-min averages and pooled to daily means - the seasonal cycle of the normalised difference vegetation index (NDVI) was calculated. In addition, a ground-based multi-channel spectroradiometer was used as a reference to estimate narrowband "green" and "red" NDVIs at weekly intervals near noon. The narrowband "green" NDVI was shown to be consistent with the simultaneous broadband 15-min NDVI. This shows that the configuration of agrometeorological radiation sensors is suitable to adequately track phenological crop dynamics. PMID:17576603

  8. Effect of radiation on cytotoxicity, apoptosis and cell cycle arrest of human osteosarcoma MG-63 induced by a ruthenium(II) complex

    NASA Astrophysics Data System (ADS)

    Liu, Si-Hong; Zhao, Jian-Hua; Deng, Kun-Kang; Wu, Yong; Zhu, Jian-Wei; Liu, Qing-Hua; Xu, Hui-Hua; Wu, Hai-Feng; Li, Xin-Yan; Wang, Jian-Wei; Guo, Qi-Feng

    2015-04-01

    Radiation has large influence on the cytotoxicity, apoptosis and cell cycle arrest. The bioactivity of ruthenium(II) complex [Ru(dmb)2(DBHIP)](ClO4)2 (Ru1) (DBHIP = 2-(3,5-dibromo-4-hydroxylphenyl)imidazo[4,5-f][1,10]phenanthroline) was investigated in the absence and presence of radiation. The cytotoxicity of Ru1 against MG-63 cells was evaluated by CCK-8 method. Ru1 shows high cytotoxicity upon radiation. Radiation can enhance the cytotoxicity of Ru1 on MG-63 cells. The apoptosis was studied by Hoechst 33258 staining method and flow cytometry. The reactive oxygen species, mitochondrial membrane potential, cell cycle arrest and western blot analysis were investigated in detail. The complex induces the apoptosis in MG-63 cells through ROS-mediated mitochondrial dysfunction pathway.

  9. Photochemistry and radiation chemistry of the β-cyclodextrin-ZnTSPP inclusion complex

    NASA Astrophysics Data System (ADS)

    Mosseri, S.; Mialocq, J. C.

    Steady-state radiolysis, pulse radiolysis combined with both optical and conductimetric analysis and steady-state photolysis have been used to characterize the intermediates and the stable products formed upon oxidation of ZnTSPP in aqueous solution in the presence and in the absence of β-cyclodextrin (β-CD). In the absence of β-CD, its oxidation either by the OH . primary species of the radiolysis of water of photooxidation by O 2 lead to mixtures of products (partially unidentified) which reflect the poor selectivity of the oxidizing species. In the presence of β-CD, a highly selective formation (99%) of the porphyrin dication is observed upon 422 nm photolysis of an aerated solution of ZnTSPP at pH = 12. The dramatic effect of the porphyrin complexation by β-CD is emphasized.

  10. EDITORIAL Complexity of advanced radiation therapy necessitates multidisciplinary inquiry into dose reconstruction and risk assessment Complexity of advanced radiation therapy necessitates multidisciplinary inquiry into dose reconstruction and risk assessment

    NASA Astrophysics Data System (ADS)

    Newhauser, Wayne

    2010-07-01

    The availability of low-cost, high-performance computing is rapidly transforming the landscape of cancer research. Computational techniques are playing an increasingly important role and have become the third major method of scientific inquiry, supplementing traditional methods of observation and theory. This evolution began in the 1940s when high-performance computing techniques were developed for military applications, including radiation transport calculations. These same basic methods are still widely utilized in a broad spectrum of computational problems in medicine, including radiation cancer therapy (Rogers 2006, Spezi 2010) and radiologic diagnostic imaging (Doi 2006, Kalender 2006). Supercomputing is also now being used to study the genetics and genomics of cancer (Geurts van Kessel 2010), with application to gene sequencing (Mardis 2008), genome-wide association studies (Pearson and Manolio 2008), biomolecular dynamics (Sanbonmatsu and Tung 2007) and systems biology (Wolkenhauer et al 2010). The extensive and growing body of literature is evidence of a remarkable expansion of activity and enormous boost to cancer research from the application of high-performance computing. Early successes were facilitated by inexpensive computing resources and advances in modeling algorithms. Many contemporary models require extensive approximations and phenomenological approaches. In fact, many critical problems remain computationally intractable; the underlying physical and biological processes are simply too complex to model with contemporary theory and computing capacity. In the future, a vast stream of new insights will flow from studies that use increasingly exact models and first-principles approaches. Hence, in the war on cancer the present status of computational research could be summarized as the beginning of the beginning. For these reasons, there is a vital need for scientists and clinicians to periodically discuss progress and future plans regarding

  11. Dose distribution of gamma radiation in a new geometric configuration of a standard carton date package and its experimental application for disinfestation of packed dates

    NASA Astrophysics Data System (ADS)

    Ahmed, M. S. H.; Al-Taweel, A. A.; Hameed, A. A.

    1994-06-01

    A new geometrical configuration composed of three standard carton boxes (SCBs) full with polyethylene bags (PBs), where each bag contains 1 kg of date, was placed on a single turntable of Gammabeam-650 and irradiated with low doses. The mean "radiation absorbed dose" for disinfestation of this geometrical unit at 15 equally distributed positions (Fricke dosimeters) inside 3 SCBs put on a single turntable was calculated to be 0.46 ± 0.20 kGy and dose uniformity ratio ( U) = 1.0019/0.2500 = 4.00. The development and genetic tests carried out on insects found in the PBs 1-2 days after irradiation resulted in that all insects were completely sterile and died within a short period of time. No sign of any reinfestation was recorded at all in the treated packages even after 30 days of storage in an insectory. Apparently the prevention of insects from invading and/or penetrating the date packages is due mainly to the new combination of standard carton boxes that are widely used for commercial purposes and hermetically heat-sealed polyethylene bags of dates in addition to the entire prevention of reproduction induced by the "low" doses of γ radiation. Therefore, by using similar geometrical configuration, 18 big standard carton date packages can be simultaneously disinfected, using the same range of doses or so, by utilizing all the 6 turntables inside the radiation chamber of the Gammabeam-650 irradiation facility.

  12. Exploiting Radiation Damage to Map Proteins in Nucleoprotein Complexes: The Internal Structure of Bacteriophage T7

    PubMed Central

    Cheng, Naiqian; Wu, Weimin; Watts, Norman R.; Steven, Alasdair C.

    2014-01-01

    In the final stage of radiation damage in cryo-electron microscopy of proteins, bubbles of hydrogen gas are generated. Proteins embedded in DNA bubble sooner than free-standing proteins and DNA does not bubble under the same conditions. These properties make it possible to distinguish protein from DNA. Here we explored the scope of this technique (“bubblegram imaging”) by applying it to bacteriophage T7, viewed as a partially defined model system. T7 has a thin-walled icosahedral capsid, 60 nm in diameter, with a barrel-shaped protein core under one of its twelve vertices (the portal vertex). The core is densely wrapped with DNA but details of their interaction and how their injection into a host bacterium is coordinated are lacking. With short (10 sec) intervals between exposures of 17 electrons/Å2 each, bubbling starts in the third exposure, with 1 – 4 bubbles nucleating in the core: in subsequent exposures, these bubbles grow and merge. A 3D reconstruction from fifth-exposure images depicts a bipartite cylindrical gas cloud in the core. In its portal-proximal half, the axial region is gaseous whereas in the portal-distal half, it is occupied by a 3 nm-wide dense rod. We propose that they respectively represent core protein and an end of the packaged genome, poised for injection into a host cell. Single bubbles at other sites may represent residual scaffolding protein. Thus, bubbling depends on dose rate, protein amount, and tightness of the DNA seal. PMID:24345345

  13. Aspects of γ-radiation induced modification of calf thymus DNA in the presence of sodium 1,4-dihydroxy-9,10-anthraquinone-2-sulfonate and its transition metal complexes with Cu2+ and Ni2+

    NASA Astrophysics Data System (ADS)

    Guin, Partha Sarathi; Mandal, Parikshit Chandra; Das, Saurabh

    2013-08-01

    Radiation-induced double-strand modification of DNA was studied in the absence and presence of sodium 1,4-dihydroxy-9,10-anthraquinone-2-sulfonate (NaQSH2) and its metal (Cu2+ and Ni2+) complexes in aerated, de-aerated (Argon saturated) and N2O saturated aqueous media at pH 7.4. Ethidium bromide, an established DNA intercalator was used to estimate DNA remaining after interaction with γ-radiation, by measuring loss of fluorescence of the ethidium bromide-DNA adduct. In de-aerated (Argon saturated) and N2O saturated aqueous media radiation-induced double-strand modification of calf thymus DNA was comparatively less in presence of NaQSH2 and its Ni(II) complex than standard control indicating the compounds behaved as radio-protectors. However, in presence of the Cu(II) complex radiation-induced double-strand modification increased significantly. In N2O saturated medium, double-strand modification of DNA was almost double in all cases than that observed in de-aerated (Argon saturated) medium indicating OH radicals played a major role in modifying DNA. That OH radicals were important was verified by repeating experiments using tertiary-butanol that showed significant decrease in DNA modification. Another important observation was in aerated medium NaQSH2, Ni(II)-NaQSH2 did not show radioprotection while Cu(II)-NaQSH2 was an almost equally effective radiosensitizer as that observed in N2O saturated medium. Role of molecular oxygen as radiosensitizer was thus realized.

  14. Key comparison BIPM.RI(I)-K5 of the air kerma standards of the ININ, Mexico and the BIPM in 137Cs gamma radiation

    NASA Astrophysics Data System (ADS)

    Kessler, C.; Burns, D. T.; Alvarez Romero, J. T.; De la Cruz Hernández, D.; Cabrera Vertti, M. R.; Tovar-Muñoz, V. M.

    2015-01-01

    A direct comparison of the standards for air kerma of the Instituto Nacional de Investigaciones Nucleares (ININ), Mexico, and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 137Cs radiation beam of the BIPM in February 2015. The comparison result, evaluated as a ratio of the ININ and the BIPM standards for air kerma, is 1.0048 with a combined standard uncertainty of 2.0 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  15. Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the NIM, China and the BIPM in 60Co gamma radiation

    NASA Astrophysics Data System (ADS)

    Kessler, C.; Burns, D.; Wang, K.; Fan, Y.; Jin, S.; Yang, X.

    2016-01-01

    An indirect comparison of the standards for air kerma of the National Institute of Metrology (NIM), China and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in November 2015. The comparison result, evaluated as a ratio of the NIM and the BIPM standards for air kerma, is 0.9997 with a combined standard uncertainty of 2.7 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  16. Deciphering the Conformational Choreography of Zinc Coordination Complexes with Standard and Novel Proton NMR Techniques Combined with DFT Methods.

    PubMed

    Pucheta, Jose Enrique Herbert; Prim, Damien; Gillet, Jean Michel; Farjon, Jonathan

    2016-04-01

    The presence of water has been shown to deeply impact the stability and geometry of Zn complexes in solution. Evidence for tetra- and penta-coordinated species in a pyridylmethylamine-Zn(II) model complex is presented. Novel (1) H NMR tools such as T1 -filtered selective exchange spectroscopy and pure shifted gradient-encoded selective refocusing as well as classical 2D ((1) H-(1) H) exchange spectroscopy, diffusion-ordered spectroscopy and T1 ((1) H) measurements, in combination with density functional theory methods allow the full conformational dynamics of a pyridylmethylamine-Zn(II) complex to be revealed. Four conformers and two families of complexes depending on the hydration states are elucidated. PMID:26845749

  17. Concerted action of Nrf2-ARE pathway, MRN complex, HMGB1 and inflammatory cytokines - Implication in modification of radiation damage

    PubMed Central

    Anuranjani; Bala, Madhu

    2014-01-01

    Whole body exposure to low linear energy transfer (LET) ionizing radiations (IRs) damages vital intracellular bio-molecules leading to multiple cellular and tissue injuries as well as pathophysiologies such as inflammation, immunosuppression etc. Nearly 70% of damage is caused indirectly by radiolysis of intracellular water leading to formation of reactive oxygen species (ROS) and free radicals and producing a state of oxidative stress. The damage is also caused by direct ionization of biomolecules. The type of radiation injuries is dependent on the absorbed radiation dose. Sub-lethal IR dose produces more of DNA base damages, whereas higher doses produce more DNA single strand break (SSBs), and double strand breaks (DSBs). The Nrf2-ARE pathway is an important oxidative stress regulating pathway. The DNA DSBs repair regulated by MRN complex, immunomodulation and inflammation regulated by HMGB1 and various types of cytokines are some of the key pathways which interact with each other in a complex manner and modify the radiation response. Because the majority of radiation damage is via oxidative stress, it is essential to gain in depth understanding of the mechanisms of Nrf2-ARE pathway and understand its interactions with MRN complex, HMGB1 and cytokines to increase our understanding on the radiation responses. Such information is of tremendous help in development of medical radiation countermeasures, radioprotective drugs and therapeutics. Till date no approved and safe countermeasure is available for human use. This study reviews the Nrf2-ARE pathway and its crosstalk with MRN-complex, HMGB1 and cytokines (TNF-a, IL-6, IFN-? etc.). An attempt is also made to review the modification of some of these pathways in presence of selected antioxidant radioprotective compounds or herbal extracts. PMID:25009785

  18. Real-time dual-mode standard/complex Fourier-domain OCT system using graphics processing unit accelerated 4D signal processing and visualization

    NASA Astrophysics Data System (ADS)

    Zhang, Kang; Kang, Jin U.

    2011-03-01

    We realized a real-time dual-mode standard/complex Fourier-domain optical coherence tomography (FD-OCT) system using graphics processing unit (GPU) accelerated 4D (3D+time) signal processing and visualization. For both standard and complex FD-OCT modes, the signal processing tasks were implemented on a dual-GPUs architecture that included λ-to-k spectral re-sampling, fast Fourier transform (FFT), modified Hilbert transform, logarithmic-scaling, and volume rendering. The maximum A-scan processing speeds achieved are >3,000,000 line/s for the standard 1024-pixel-FD-OCT, and >500,000 line/s for the complex 1024-pixel-FD-OCT. Multiple volumerendering of the same 3D data set were preformed and displayed with different view angles. The GPU-acceleration technique is highly cost-effective and can be easily integrated into most ultrahigh speed FD-OCT systems to overcome the 3D data processing and visualization bottlenecks.

  19. Method for the calibration of the spectral irradiance of tungsten filament transfer standard sources traceable to synchrotron radiation.

    PubMed

    Anevsky, Sergey; Krutikov, Vladimir; Minaeva, Olga; Minaev, Roman; Senin, Dmitriy; Hollandt, Jörg; Taubert, Dieter R

    2013-07-20

    The spectral irradiance calibration of tungsten strip and spiral filament lamps applying synchrotron radiation revealed that the spectral irradiance in the wavelength range from 280 to 400 nm can be well approximated by blackbody radiation according to Planck's law. Consequently, the spectral irradiance of the filament lamp can then be described by an effective irradiance temperature, which would be beneficial for practical measurements. Including the emissivity of tungsten into the approximation, the model can be expanded to visible and near-infrared wavelength regions. The effective irradiance temperature dependence of the lamp current was investigated and appeared to be close to linear. PMID:23872760

  20. [Improved results of the trachea scar stenosis treatment by inclusion in the complex therapy of combined application diprospan and low-intensity infrared laser radiation].

    PubMed

    Israfilova, S B; Gasymov, É M

    2013-09-01

    The experience of treating 61 patients over the rumen of stenosis of the trachea was summarizes. To improve the results suggested inclusion complex diprospan treatment in combination with low intensity infrared laser radiation. The advantages of the proposed method of treatment of tracheal stenosis scarring are reduced severity of chronic inflammation, reducing the proliferation of granulation tissue. PMID:24501929

  1. Radiation hybrid maps of D-genome of Aegilops tauschii and their application in sequence assembly of large and complex plant genomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The large and complex genome of bread wheat (Triticum aestivum L., ~17 Gb) requires high-resolution genome maps saturated with ordered markers to assist in anchoring and orienting BAC contigs/ sequence scaffolds for whole genome sequence assembly. Radiation hybrid (RH) mapping has proven to be an e...

  2. Noise-immune complex correlation for vasculature imaging based on standard and Jones-matrix optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Makita, Shuichi; Kurokawa, Kazuhiro; Hong, Young-Joo; Li, En; Miura, Masahiro; Yasuno, Yoshiaki

    2016-03-01

    A new optical coherence angiography (OCA) method, called correlation mapping OCA (cmOCA), is presented by using the SNR-corrected complex correlation. An SNR-correction theory for the complex correlation calculation is presented. The method also integrates a motion-artifact-removal method for the sample motion induced decorrelation artifact. The theory is further extended to compute more reliable correlation by using multi- channel OCT systems, such as Jones-matrix OCT. The high contrast vasculature imaging of in vivo human posterior eye has been obtained. Composite imaging of cmOCA and degree of polarization uniformity indicates abnormalities of vasculature and pigmented tissues simultaneously.

  3. The screened hydrogenic model: Analytic formulae for matrix elements of radiative and collisional rates in complex ions

    NASA Astrophysics Data System (ADS)

    Upcraft, L. M.

    2010-09-01

    There is an ongoing need for numerically efficient algorithms that are capable of calculating the radiative and collisional rates of arbitrarily complex ions that are present in hot plasmas to a level of accuracy that surpasses that available in many existing approximations. Hydrogen-like solutions for determining these rates in more general ions by use of an effective (and generally non-integer) atomic number frequently give poor results and are of limited validity. This paper illustrates that results accurate to of order 20% can be obtained for matrix elements of both rates for arbitrarily complex ions by use of hydrogenic wavefunctions that use different effective atomic numbers for the initial and final sub-shells. Not only does this allow for the realistic modelling of inner shell transitions, it naturally allows for the physical effect of orbital relaxation. It is shown that the integral of the generalised oscillator strength used by the Plane-wave Born approximation has an analytic solution that can be reduced to a form suitable for efficient numerical integration over an arbitrary electron distribution. Extensive use of the computer algebra package Mathematica ® has generated a unique formula for each transition and the results have been transformed to efficient fortran 90 code for all transitions between non-relativistic sub-shells with principal quantum numbers n ≤ 10. In the case of the collisional matrix elements these are typically two to three orders of magnitude faster to calculate than by direct numerical evaluation. The fortran code is available upon request from the author.

  4. EDITORIAL Complexity of advanced radiation therapy necessitates multidisciplinary inquiry into dose reconstruction and risk assessment Complexity of advanced radiation therapy necessitates multidisciplinary inquiry into dose reconstruction and risk assessment

    NASA Astrophysics Data System (ADS)

    Newhauser, Wayne

    2010-07-01

    The availability of low-cost, high-performance computing is rapidly transforming the landscape of cancer research. Computational techniques are playing an increasingly important role and have become the third major method of scientific inquiry, supplementing traditional methods of observation and theory. This evolution began in the 1940s when high-performance computing techniques were developed for military applications, including radiation transport calculations. These same basic methods are still widely utilized in a broad spectrum of computational problems in medicine, including radiation cancer therapy (Rogers 2006, Spezi 2010) and radiologic diagnostic imaging (Doi 2006, Kalender 2006). Supercomputing is also now being used to study the genetics and genomics of cancer (Geurts van Kessel 2010), with application to gene sequencing (Mardis 2008), genome-wide association studies (Pearson and Manolio 2008), biomolecular dynamics (Sanbonmatsu and Tung 2007) and systems biology (Wolkenhauer et al 2010). The extensive and growing body of literature is evidence of a remarkable expansion of activity and enormous boost to cancer research from the application of high-performance computing. Early successes were facilitated by inexpensive computing resources and advances in modeling algorithms. Many contemporary models require extensive approximations and phenomenological approaches. In fact, many critical problems remain computationally intractable; the underlying physical and biological processes are simply too complex to model with contemporary theory and computing capacity. In the future, a vast stream of new insights will flow from studies that use increasingly exact models and first-principles approaches. Hence, in the war on cancer the present status of computational research could be summarized as the beginning of the beginning. For these reasons, there is a vital need for scientists and clinicians to periodically discuss progress and future plans regarding

  5. Crafting Coherence from Complex Policy Messages: Educators' Perceptions of Special Education and Standards-Based Accountability Policies

    ERIC Educational Resources Information Center

    Russell, Jennifer Lin; Bray, Laura E.

    2013-01-01

    Federal special education and accountability policies requires that educators individualize instruction for students with disabilities, while simultaneously ensuring that the vast majority of these students meet age-based grade-level standards and assessment targets. In this paper, we examine this dynamic interplay between policies through…

  6. 76 FR 4944 - Ionizing Radiation Standard; Extension of the Office of Management and Budget's (OMB) Approval of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-27

    .... 3506 et seq.) and Secretary of Labor's Order No. 4-2010 (75 FR 55355). Signed at Washington, DC, on... may result from occupational exposure to ionizing radiation including tissue damage and cancer. DATES... Labor, as part of its continuing effort to reduce paperwork and respondent (i.e., employer)...

  7. Reducing Climate Information Complexity through the Production of a Standard Scenarios Ensemble for Vulnerability, Impact and Adaptation Applications

    NASA Astrophysics Data System (ADS)

    Gauvin St-Denis, B.; Logan, T.; Braun, M.; Gampe, D.; Chaumont, D.

    2014-12-01

    With the growing number of available climate simulations, the capacity of end users to process and interpret all this information in vulnerability, impact and adaptation studies becomes limited. At the same time, for an organization providing climate scenarios and services, it is important to provide scenarios that will ensure comparable and coherent decision making across various projects, while still addressing their particularities. Here, the choices and challenges related to the production of a standard climate scenarios ensemble are presented. The resulting ensemble should be standard in terms of climate simulations used and post-processing methods applied. Furthermore, the uncertainty present in the full original ensemble should be appropriately represented for all time horizons, spatial locations and scales, and variables. Starting from the CMIP5 ensemble, an objective selection of simulations is done using cluster analysis. Biases in climate simulations are characterized and simple post-processing methods are used to correct those biases, with particular interest in preserving the effects of natural variability. With such a standard climate scenarios ensemble, it is possible to provide condensed, but still adequate, climate information accompanied by a well-documented methodology. These products, with related knowledge transfer associated to underlying uncertainties, as well as interactions with end users form the basis for successful adaptation decisions.

  8. Radiation occupational health interventions offered to radiation workers in response to the complex catastrophic disaster at the Fukushima Daiichi Nuclear Power Plant

    PubMed Central

    Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Okuda, Kengo; Svendsen, Erik Robert; Kunugita, Naoki

    2015-01-01

    The Fukushima Daiichi Nuclear Power Plant (NPP) 1 was severely damaged from the chain reaction of the Great East Japan Earthquake and Tsunami on 11 March 2011, and the consequent meltdown and hydrogen gas explosions. This resulted in the worst nuclear accident since the Chernobyl accident of 1986. Just as in the case of Chernobyl, emergency workers were recruited to conduct a wide range of tasks, including disaster response, rescuing activities, NPP containment, and radiation decontamination. This paper describes the types and efficacy of the various occupational health interventions introduced to the Fukushima NPP radiation workers. Such interventions were implemented in order to prevent unnecessary radiation overexposure and associated adverse health effects and work injuries. Less than 1% of all emergency workers were exposed to external radiation of >100 mSv, and to date no deaths or health adversities from radiation have been reported for those workers. Several occupational health interventions were conducted, including setting of new regulatory exposure limits, improving workers' radiation dosimetry, administration of stable iodine, running an occupational health tracking system, and improving occupational medicine and preventative care. Those interventions were not only vital for preventing unnecessary radiation, but also for managing other general health issues such as mental health, heat illness and infectious diseases. Long-term administration of the aforementioned occupational health interventions is essential to ensure the ongoing support and care for these workers, who were put under one of the most severe occupational health risk conditions ever encountered. PMID:25413928

  9. Radiation occupational health interventions offered to radiation workers in response to the complex catastrophic disaster at the Fukushima Daiichi Nuclear Power Plant.

    PubMed

    Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Okuda, Kengo; Svendsen, Erik Robert; Kunugita, Naoki

    2015-05-01

    The Fukushima Daiichi Nuclear Power Plant (NPP) 1 was severely damaged from the chain reaction of the Great East Japan Earthquake and Tsunami on 11 March 2011, and the consequent meltdown and hydrogen gas explosions. This resulted in the worst nuclear accident since the Chernobyl accident of 1986. Just as in the case of Chernobyl, emergency workers were recruited to conduct a wide range of tasks, including disaster response, rescuing activities, NPP containment, and radiation decontamination. This paper describes the types and efficacy of the various occupational health interventions introduced to the Fukushima NPP radiation workers. Such interventions were implemented in order to prevent unnecessary radiation overexposure and associated adverse health effects and work injuries. Less than 1% of all emergency workers were exposed to external radiation of >100 mSv, and to date no deaths or health adversities from radiation have been reported for those workers. Several occupational health interventions were conducted, including setting of new regulatory exposure limits, improving workers' radiation dosimetry, administration of stable iodine, running an occupational health tracking system, and improving occupational medicine and preventative care. Those interventions were not only vital for preventing unnecessary radiation, but also for managing other general health issues such as mental health, heat illness and infectious diseases. Long-term administration of the aforementioned occupational health interventions is essential to ensure the ongoing support and care for these workers, who were put under one of the most severe occupational health risk conditions ever encountered. PMID:25413928

  10. Noise-immune complex correlation for optical coherence angiography based on standard and Jones matrix optical coherence tomography

    PubMed Central

    Makita, Shuichi; Kurokawa, Kazuhiro; Hong, Young-Joo; Miura, Masahiro; Yasuno, Yoshiaki

    2016-01-01

    This paper describes a complex correlation mapping algorithm for optical coherence angiography (cmOCA). The proposed algorithm avoids the signal-to-noise ratio dependence and exhibits low noise in vasculature imaging. The complex correlation coefficient of the signals, rather than that of the measured data are estimated, and two-step averaging is introduced. Algorithms of motion artifact removal based on non perfusing tissue detection using correlation are developed. The algorithms are implemented with Jones-matrix OCT. Simultaneous imaging of pigmented tissue and vasculature is also achieved using degree of polarization uniformity imaging with cmOCA. An application of cmOCA to in vivo posterior human eyes is presented to demonstrate that high-contrast images of patients’ eyes can be obtained. PMID:27446673

  11. An analytical method for estimating the {sup 14}N nuclear quadrupole resonance parameters of organic compounds with complex free induction decays for radiation effects studies

    SciTech Connect

    Iselin, L.H.

    1992-12-31

    The use of {sup 14}N nuclear quadrupole resonance (NQR) as a radiation dosimetry tool has only recently been explored. An analytical method for analyzing {sup 14}N NQR complex free induction decays is presented with the background necessary to conduct pulsed NQR experiments. The {sup 14}N NQR energy levels and possible transitions are derived in step-by-step detail. The components of a pulsed NQR spectrometer are discussed along with the experimental techniques for conducting radiation effects experiments using the spectrometer. Three data analysis techniques -- the power spectral density Fourier transform, state space singular value decomposition (HSVD), and nonlinear curve fitting (using the downhill simplex method of global optimization and the Levenberg-Marquart method) -- are explained. These three techniques are integrated into an analytical method which uses these numerical techniques in this order to determine the physical NQR parameters. Sample data sets of urea and guanidine sulfate data are used to demonstrate how these methods can be employed to analyze both simple and complex free induction decays. By determining baseline values for biologically significant organics, radiation effects on the NQR parameters can be studied to provide a link between current radiation dosimetry techniques and the biological effects of radiation.

  12. Key comparison BIPM.RI(I)-K4 of the absorbed dose to water standards of the PTB, Germany and the BIPM in 60Co gamma radiation

    NASA Astrophysics Data System (ADS)

    Kessler, C.; Burns, D. T.; Kapsch, R.-P.; Krauss, A.

    2016-01-01

    An indirect comparison has been made of the standards for absorbed dose to water in 60Co radiation of the Physikalisch-Technische Bundesanstalt, (PTB), Germany and of the Bureau International des Poids et Mesures (BIPM). The measurements at the BIPM were carried out in October 2015. The comparison result, based on the calibration coefficients for two transfer standards and evaluated as a ratio of the PTB and the BIPM standards for absorbed dose to water, is 0.9977 with a combined standard uncertainty of 3.8 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  13. Chemical Effect on K Shell X-ray Fluorescence Parameters and Radiative Auger Ratios of Co, Ni, Cu, and Zn Complexes

    NASA Astrophysics Data System (ADS)

    Cengiz, Erhan; Bıyıklıoğlu, Zekeriya; Küp Aylıkcı, Nuray; Aylıkcı, Volkan; Apaydın, Gökhan; Tıraşoğlu, Engin; Kantekin, Halit

    2010-04-01

    The production cross-sections, intensity ratios, and radiative Auger intensity ratios of Co, Ni, Cu, and Zn elements in different complexes were measured. The chemical effects on the K shell fluorescence parameters and the radiative Auger intensity ratios of these elements were investigated and the changes in these parameters were interpreted according to the charge transfer process. The samples were excited by 59.5 keV γ-rays from a 241Am annular radioactive source. K X-rays emitted by samples were counted by an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV.

  14. Modulation of keratin 1, 10 and involucrin expression as part of the complex response of the human keratinocyte cell line HaCaT to ultraviolet radiation

    PubMed Central

    Moravcová, Martina; Libra, Antonín; Dvořáková, Jana; Víšková, Alena; Muthný, Tomáš; Velebný, Vladimír

    2013-01-01

    Skin exposure to ultraviolet (UV) light evokes a complex stress response in keratinocytes. Keratin filament organization provides structural stability and mechanical integrity of keratinocytes. Involucrin is a transglutaminase substrate protein contributing to the formation of insoluble cornified envelopes. However, a more complex role for keratins and involucrin has been proposed, including the regulation of cell stress response. The aim was to evaluate modulations of keratin 1, 10 and involucrin expression in HaCaT in the light of the complex response of these cells to UV-B radiation, including effects on c-Jun and matrix metalloproteinase 1 (MMP-1) gene expression and production of interleukin (IL) 6 and 8. A UV-B (300±5 nm) dose of 10 mJ/cm2 was selected since this dose resulted in a partial decrease in cell viability in contrast to higher UV-B doses, which induced complete cell death 48 h after treatment. The UV-B radiation induced significant expression of keratin 1 and 10 and decreased expression of involucrin. This was accompanied by increased expression of c-Jun and MMP-1 and IL-6 and IL-8 production. The data suggest that the expression of keratin 1, 10 and involucrin is modulated in HaCaT keratinocytes as a part of the complex stress response to UV radiation. PMID:24678259

  15. An internal standard approach for homogeneous TR-FRET immunoassays facilitates the detection of bacteria, biomarkers, and toxins in complex matrices.

    PubMed

    Cohen, Noam; Zahavy, Eran; Zichel, Ran; Fisher, Morly

    2016-07-01

    The recent development of a homogeneous time-resolved Förster resonance energy transfer (TR-FRET) immunoassay enables one-step, rapid (minutes), and direct detection compared to the multistep, time-consuming (hours), heterogeneous ELISA-type immunoassays. The use of the time-resolved effect of a donor lanthanide complex with a delay time of microseconds and large Stokes shift enables the separation of positive signals from the background autofluorescence of the sample. However, this study shows that the sample matrices directly interfere with donor fluorescence and that interference cannot be eliminated by time-resolved settings alone. Moreover, the reduction in donor emission did not appear to be equivalent to the reduction in acceptor emission, resulting in incorrect FRET signal measurements. To overcome this limitation, an internal standard approach was developed using an isotype control antibody. This new approach was used to develop TR-FRET assays for rapid detection (15-30 min) of Bacillus anthracis spores and botulinum toxin (type E) in beverages, which are major concerns in bioterrorism involving deliberate food contamination. Additionally, we demonstrate the detection of B. anthracis-secreted protective antigen (PA) and the Yersinia pestis-secreted markers F1 and LcrV in blood cultures, which are early markers of bacteremia in infected hosts following a possible bioterror attack. The use of an internal standard enables the calculation of correct ΔF values without the need for an external standard. Thus, the use of the internal standard approach in homogeneous immunoassays facilitates the examination of any sample regardless of its origin, and therefore expands the applicability of TR-FRET assays for complex matrices. PMID:27236318

  16. Characterization of Zn(q+)-imidazole (q = 0, 1, 2) organometallic complexes: DFT methods vs. standard and explicitly correlated post-Hartree-Fock methods.

    PubMed

    Boussouf, K; Boulmene, R; Prakash, M; Komiha, N; Taleb, M; Mogren Al-Mogren, M; Hochlaf, M

    2015-06-14

    In the present work, we investigate the bonding, structures, stability and spectra of the Zn(q+)Im (where q = 0, 1, and 2) complexes, which are zeolitic imidazolate frameworks (ZIFs) and Zn-enzyme sub-units. Through a benchmark work, we used density functional theory (DFT) with dispersion correction and standard and explicitly correlated ab initio methods. For neutral Zn(0)Im, we found two stable weakly bound forms: (i) a stacked ferrocene-like complex and (ii) a planar σ-type complex. This is the first report of the Zn(0) organic compound with a stacked ferrocene-like structure. The most stable isomers of the ionic species consist of σ-type bonded complexes. The role of various types of covalent and noncovalent interactions within these complexes is discussed after performing vibrational, NBO, charge and orbital analyses. For neutral species, van der Waals (vdWs) and charge transfer through covalent as well as noncovalent interactions are in action; whereas the bonding is dominated by charge transfer from Zn to Im within the ionic species. These findings are important to understand, at the microscopic level, the structure and the bonding within the ZIFs and the Zn-enzymes. Moreover, we establish the ability and reliability of M05-2X and PBE0 functionals for the simultaneous correct description of covalent and noncovalent interactions since this DFT leads to a close agreement with post-Hartree-Fock methods. The newly launched M11 functional is also suited for the description of noncovalent interactions. Therefore, M05-2X and PBE0 functionals are recommended for studying the larger complexes formed by Zn and Im, such as the ZIFs and Zn-enzymes. PMID:25920409

  17. Assessing the compatibility of the management of standardized procedures with the complexity of a sociotechnical system: case study of a control room in an oil refinery.

    PubMed

    Saurin, Tarcisio Abreu; Gonzalez, Santiago Sosa

    2013-09-01

    Although the need for the management of complex socio-technical systems (STS) to be compatible with the nature of those systems is widely recognized, there are few guidelines on how to determine the actual extent of this compatibility. The purpose of this study is to assess how compatible the management of standardized procedures (SPs) is with the nature of a complex STS. To this end, a case study was made of a control room in an oil refinery, involving the following stages: (a) delimitation of the investigated STS; (b) description of the STS according to a set of characteristics of complex STS; (c) application of two types of questionnaires to thirty workers - one of them to assess their perceptions about the applicability of seven principles of SPs management in complex STS and the other to determine their perceptions about the actual use of these principles; and (d) a feedback meeting with workers to discuss the results of the assessment. The assessment is discussed in terms of its limitations, usefulness and ease of use of the data collection and analysis tools. PMID:23465943

  18. Functional analysis via standardized whole-blood stimulation systems defines the boundaries of a healthy immune response to complex stimuli.

    PubMed

    Duffy, Darragh; Rouilly, Vincent; Libri, Valentina; Hasan, Milena; Beitz, Benoit; David, Mikael; Urrutia, Alejandra; Bisiaux, Aurélie; Labrie, Samuel T; Dubois, Annick; Boneca, Ivo G; Delval, Cécile; Thomas, Stéphanie; Rogge, Lars; Schmolz, Manfred; Quintana-Murci, Lluis; Albert, Matthew L

    2014-03-20

    Standardization of immunophenotyping procedures has become a high priority. We have developed a suite of whole-blood, syringe-based assay systems that can be used to reproducibly assess induced innate or adaptive immune responses. By eliminating preanalytical errors associated with immune monitoring, we have defined the protein signatures induced by (1) medically relevant bacteria, fungi, and viruses; (2) agonists specific for defined host sensors; (3) clinically employed cytokines; and (4) activators of T cell immunity. Our results provide an initial assessment of healthy donor reference values for induced cytokines and chemokines and we report the failure to release interleukin-1α as a common immunological phenotype. The observed naturally occurring variation of the immune response may help to explain differential susceptibility to disease or response to therapeutic intervention. The implementation of a general solution for assessment of functional immune responses will help support harmonization of clinical studies and data sharing. PMID:24656047

  19. Standard and goal-oriented adaptive mesh refinement applied to radiation transport on 2D unstructured triangular meshes

    SciTech Connect

    Yaqi Wang; Jean C. Ragusa

    2011-02-01

    Standard and goal-oriented adaptive mesh refinement (AMR) techniques are presented for the linear Boltzmann transport equation. A posteriori error estimates are employed to drive the AMR process and are based on angular-moment information rather than on directional information, leading to direction-independent adapted meshes. An error estimate based on a two-mesh approach and a jump-based error indicator are compared for various test problems. In addition to the standard AMR approach, where the global error in the solution is diminished, a goal-oriented AMR procedure is devised and aims at reducing the error in user-specified quantities of interest. The quantities of interest are functionals of the solution and may include, for instance, point-wise flux values or average reaction rates in a subdomain. A high-order (up to order 4) Discontinuous Galerkin technique with standard upwinding is employed for the spatial discretization; the discrete ordinates method is used to treat the angular variable.

  20. Acid phosphatase complex from the freshwater snail Viviparus viviparus L. under standard conditions and intoxication by cadmium ions.

    PubMed

    Tsvetkov, I L; Popov, A P; Konichev, A S

    2003-12-01

    Acid phosphatases differing in both subcellular localization and substrate specificity were isolated for the first time from the liver of the freshwater snail Viviparus viviparus L. by preparative isoelectrofocusing. One of five characterized phosphatases is highly specific to ADP and the others can hydrolyze (at variable rate) a series of natural substrates. A scheme is proposed for the involvement of the studied phosphatases in carbohydrate metabolism. We have also studied some peculiarities of the effect of Cd2+ in vitro and in vivo on the activities of individual components of the acid phosphatase complex and corresponding changes in metabolism of the freshwater snail as a new test-object allowing the estimation of toxicity in water. PMID:14756629

  1. Elementally specific electron-positron annihilation radiation emitted from ion cores of group-V impurity-vacancy complexes in germanium

    NASA Astrophysics Data System (ADS)

    Arutyunov, N. Yu.; Emtsev, V. V.

    2007-12-01

    High-momentum component (HMC) of the electron-positron annihilation has been detected by the angular correlation of annihilation radiation (ACAR) technique in order to obtain elementally specific information about the ion cores of the donor-vacancy complexes (DV) formed by irradiation with 60Co γ-rays at Tirr.≈280 K in oxygen-lean n-Ge doped with group-V donors (D=As, Sb, and Bi). The probability of annihilation of positrons with the core electrons of DV complexes reconstructed from ACAR spectra increases in passing from AsV to SbV and BiV complexes. This increase correlates with the shift of the D atom from its regular position towards the vacancy site predicted by the results of spin-density functional modeling study. The data obtained suggest inward relaxation of the ion cores of DV complexes (including the one directed inward towards the vacancy).

  2. Complexation of metal ion with poly(1-vinylimidazole) resin prepared by radiation-induced polymerization with template metal ion. [Gamma radiation

    SciTech Connect

    Kato, M.; Nishide, H.; Tsuchida, E.; Sasaki, T.

    1981-07-01

    Poly(1-vinylimidazole) (PVI) resin was prepared with Ni/sup 2 +/, CO/sup 2 +/, or Zn/sup 2 +/ as a template to study the adsorption of metal ions. The metal-1-vinylimidazole complex was copolymerized and cross-linked with 1-vinyl-2-pyrrolidone by ..gamma..-ray irradiation and the template metal ion was removed by treating the polymer complex with an acid. These PVI resins adsorbed metal ions more effectively than the PVI resin prepared without the template. The number of adsorption sites (As) and the stability constant (K) of Ni/sup 2 +/ complex were larger for the PVI resin prepared with the Ni ion template caused by the smaller dissociation rate constant of Ni ion from the resin. The composition of the Ni/sup 2 +/ complex in the resin remained constant. This suggests that the complexation proceeded via a one-step mechanism.

  3. The problems associated with the monitoring of complex workplace radiation fields at European high-energy accelerators and thermonuclear fusion facilities.

    PubMed

    Bilski, P; Blomgren, J; d'Errico, F; Esposito, A; Fehrenbacher, G; Fernàndez, F; Fuchs, A; Golnik, N; Lacoste, V; Leuschner, A; Sandri, S; Silari, M; Spurny, F; Wiegel, B; Wright, P

    2007-01-01

    The European Commission is funding within its Sixth Framework Programme a three-year project (2005-2007) called CONRAD, COordinated Network for RAdiation Dosimetry. The organisational framework for this project is provided by the European Radiation Dosimetry Group EURADOS. One task within the CONRAD project, Work Package 6 (WP6), was to provide a report outlining research needs and research activities within Europe to develop new and improved methods and techniques for the characterisation of complex radiation fields at workplaces around high-energy accelerators, but also at the next generation of thermonuclear fusion facilities. The paper provides an overview of the report, which will be available as CERN Yellow Report. PMID:17496292

  4. Calibrating the light pulse shape of a hydrogen flashlamp using synchrotron radiation as a standard of excitation.

    PubMed

    Andre, J C; Lopez-Delgado, R; Lyke, R L; Ware, W R

    1979-05-01

    Advantage has been taken of the measured pulse width of synchrotron radiation and its independence of wavelength to determine the delta-pulse response of a vacuum uv photomultiplier. This photomultiplier was then used to establish the true time profile of a nanosecond H(2) flashlamp. Two numerical techniques (the exponential series method and the fast Fourier transform method) were used to deconvolute the data arising from these experiments. The results indicate that the H(2) flashlamp probably has the same profile in the many-line region, lambda < 1800 A, and in the continuum region, lambda > 2100 A, and the delta-pulse response of the PMT appears consistent with known properties of the Cs-Te photocathode. PMID:20212849

  5. Estimation of a Self-Consistent Set of Radiobiological Parameters From Hypofractionated Versus Standard Radiation Therapy of Prostate Cancer

    SciTech Connect

    Pedicini, Piernicola; Strigari, Lidia; Benassi, Marcello

    2013-04-01

    Purpose: To determine a self-consistent set of radiobiological parameters in prostate cancer. Methods and Materials: A method to estimate intrinsic radiosensitivity (α), fractionation sensitivity (α/β), repopulation doubling time, number of clonogens, and kick-off time for accelerated repopulation of prostate cancer has been developed. Based on the generalized linear-quadratic model and without assuming the isoeffective hypothesis, the potential applications of the method were investigated using the clinical outcome of biochemical relapse-free survival recently reviewed in the literature. The strengths and limitations of the method, regarding the fitted parameters and 95% confidence intervals (CIs), are also discussed. Results: Our best estimate of α/β is 2.96 Gy (95% CI 2.41-3.53 Gy). The corresponding α value is 0.16 Gy{sup −1} (95% CI 0.14-0.18 Gy{sup −1}), which is compatible with a realistic number of clonogens: 6.5 × 10{sup 6} (95% CI 1.5 × 10{sup 6}-2.1 × 10{sup 7}). The estimated cell doubling time is 5.1 days (95% CI 4.2-7.2 days), very low if compared with that reported in the literature. This corresponds to the dose required to offset the repopulation occurring in 1 day of 0.52 Gy/d (95% CI 0.32-0.68 Gy/d). However, a long kick-off time of 31 days (95% CI 22-41 days) from the start of radiation therapy was found. Conclusion: The proposed analytic/graphic method has allowed the fitting of clinical data, providing a self-consistent set of radiobiological parameters for prostate cancer. With our analysis we confirm a low value for α/β with a correspondingly high value of intrinsic radiosensitivity, a realistic average number of clonogens, a long kick-off time for accelerated repopulation, and a surprisingly fast repopulation that suggests the involvement of subpopulations of specifically tumorigenic stem cells during continuing radiation therapy.

  6. In Vivo Comparison of Radiation Exposure of Dual-Energy CT Versus Low-Dose CT Versus Standard CT for Imaging Urinary Calculi

    PubMed Central

    Jepperson, Maria A.; Cernigliaro, Joseph G.; Ibrahim, El-Sayed H.; Morin, Richard L.; Haley, William E.

    2015-01-01

    Abstract Purpose: Dual-energy computed tomography (DECT) is an emerging imaging modality with the unique capability of determining urinary stone composition. This study compares radiation exposure of DECT, standard single-energy CT (SECT), and low-dose renal stone protocol single-energy CT (LDSECT) for the evaluation of nephrolithiasis in a single in vivo patient cohort. Materials and Methods: Following institutional review board (IRB) approval, we retrospectively reviewed 200 consecutive DECT examinations performed on patients with suspected urolithiasis over a 6-month period. Of these, 35 patients had undergone examination with our LDSECT protocol, and 30 patients had undergone examination of the abdomen and pelvis with our SECT imaging protocol within 2 years of the DECT examination. The CT dose index volume (CTDIvol) was used to compare radiation exposure between scans. Image quality was objectively evaluated by comparing image noise. Statistical evaluation was performed using a Student's t-test. Results: DECT performed at 80/140 kVp and 100/140 kVp did not produce a significant difference in radiation exposure compared with LDSECT (p=0.09 and 0.18, respectively). DECT performed at 80/140 kVp and 100/140 kVp produced an average 40% and 31%, respectively, reduction in radiation exposure compared with SECT (p<0.001). For patients imaged with the 100/140 kVp protocol, average values for images noise were higher in the LDSECT images compared with DECT images (p<0.001) and there was no significant difference in image noise between DECT and SECT images in the same patient (p=0.88). Patients imaged with the 80/140 kVp protocol had equivocal image noise compared with LDSECT images (p=0.44), however, DECT images had greater noise compared with SECT images in the same patient (p<0.001). Of the 75 patients included in the study, stone material was available for 16; DECT analysis correctly predicted stone composition in 15/16 patients (93%). Conclusion: DECT

  7. Severity levels and symptoms complexes for acute radiation sickness -- description and quantification. Technical report, 6 January 1984-31 March 1985

    SciTech Connect

    Anno, G.H.; Wilson, D.B.; Baum, S.J.

    1985-11-30

    This report develops a descriptive/quantifying structure to express and gage the severity of symptoms, from symptom complexes, and construct a dose/time map of the symptom sequelae following prompt ionizing-radiation exposure and injury in humans. Radiation doses in the range of 75 to 4500 rads and postexposure time up to 6 weeks are considered. Symptom-severity levels, ranging from level 1 (no apparent effect) to level 5 (maximum severity), are defined for each of 6 symptoms categories including: (1) upper gastro-intestinal distress, (2) lower GI distress, (3) fatigability and weakness, (4) hypotension, (5) infection, bleeding, and fever, and (6) fluid loss and electrolyte imbalance. Temporal profiles of symptom severity are developed for the 6 symptom categories as well as for the symptom complexes formed by combining each symptom category according to severity level along postexposure time. About 100 different symptom complexes cover the dose and time ranges of interest. A dose/time mapping of the symptom complexes was used to select 30 to 40 of the most important ones. Those were included on U.S. Army questionnaires designed to obtain personnel judgments of task performance under various degress of debilitation. The incidence of upper GI distress, lower GI distress, fatigability and weakness, and early diarrhea are estimated based on probit and logit analyses of medical data.

  8. Influence of instability of laser radiation on accuracy of record and reading of the information of diagnostic complex Intest 1

    NASA Astrophysics Data System (ADS)

    Moguilnaia, T. Y.; Botikov, A.; Agibalov, A. A.; Kosenkov, E.

    2005-09-01

    The theoretical and the experimental researches of spectra of absent-minded radiation in medium containing viruses of the influenza, the hepatitis C and smallpox of the rabbit were carried out. The noises arising at a stage of generation of radiation in biological structure of a virus have been investigated. It has been shown, that the intensity of the parasitic luminescence is the least if solvent is alcohol and the greatest if solvent is water.

  9. Application of the discrete ordinates method to combined conductive and radiative heat transfer in a two-dimensional complex geometry.

    NASA Astrophysics Data System (ADS)

    Sakami, M.; Charette, A.; Le Dez, V.

    1996-10-01

    This paper describes a new approach for determining the radiative intensity and temperature fields in a semi-transparent medium for coupled radiative - conductive heat transfer in two-dimensional enclosures. The boundary surfaces are uniformly gray with prescribed emissivities and temperatures. The medium is radiatively absorbing - emitting - scattering and gray. The method is a modification of the discrete ordinates method based on the incorporation of directional ray propagation relations within the cells. The algorithm is applicable to enclosures of arbitrary geometry and does not generate numerical oscillations and negative intensities which can appear in the traditional technique. This is made possible by solving the radiative transfer equation exactly along a set of discretized directions. The method can handle triangular grids of any type, structured or unstructured, and is thus compatible with the finite element technique - which is used for the conduction part of the present coupled problem. A summary of the basic equations is given, followed by a brief assessment of the method for pure radiation. Cases of combined conduction - radiation are then presented and the results are compared with those obtained by other researchers. It is shown that the method has no limitation with respect to geometry and is accurate over a wide range of optical thicknesses.

  10. [Substantiation of a complex of radiation-hygienic approaches to the management of very low-level waste].

    PubMed

    Korenkov, I P; Lashchenova, T N; Shandala, N K

    2015-01-01

    In the article there are presented materials on radiation-hygienic approaches to the treatment of very low level radioactive waste (VLLW) and industrial waste containing radionuclides. There is done detailed information on radiation-hygienic principles and criteria for the assurance ofradiation safety in the collection, transportation, storage and processing of VLLW as a category of radioactive waste.. Particular attention is paid to the problem of designing VLLW landfill site choice, system of radiation monitoring in operation and decommissioning of the landfill. There are presented data about the criteria for the release of VLLW buried at the site, from regulatory control. Also there are considered in detail the radiation-hygienic requirements for radiation safety of industrial waste containing radionuclides for which there is assumed unlimited and limited use of solid materials in economic activity, based on the requirements ofthe revised Basic Sanitary Rules for Radiation Safety - 99/2010. There are considered basic requirements for the organization of industrial waste landfill. As an example, there-are presented the hygiene requirements for industrial waste management and results of waste categorization in Northern Federal Enterprise for Radioactive Waste Management. PMID:26031036

  11. Complex Parts, Complex Data: Why You Need to Understand What Radiation Single Event Testing Data Does and Doesn't Show and the Implications Thereof

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Berg, Melanie D.

    2015-01-01

    Electronic parts (integrated circuits) have grown in complexity such that determining all failure modes and risks from single particle event testing is impossible. In this presentation, the authors will present why this is so and provide some realism on what this means. Its all about understanding actual risks and not making assumptions.

  12. Complex Parts, Complex Data: Why You Need to Understand What Radiation Single Event Testing Data Does and Doesn't Show and the Implications Thereof

    NASA Technical Reports Server (NTRS)

    Label, Kenneth A.; Berg, Melanie D.

    2016-01-01

    Electronic parts (integrated circuits) have grown in complexity such that determining all failure modes and risks from single particle event testing is impossible. In this presentation, the authors will present why this is so and provide some realism on what this means. Its all about understanding actual risks and not making assumptions.

  13. Distilling Complex Model Results into Simple Models for use in Assessing Compliance with Performance Standards for Low Level Waste Disposal Facilities

    SciTech Connect

    Arthur S. Rood

    2007-02-01

    Assessing the long term performance of waste disposal facility requires numerical simulation of saturated and unsaturated groundwater flow and contaminant transport. Complex numerical models have been developed to try to realistically simulate subsurface flow and transport processes. These models provide important information about system behavior and identify important processes, but may not be practical for demonstrating compliance with performance standards because of excessively long computer simulation times and input requirements. Two approaches to distilling the behavior of a complex model into simpler formulations that are practical for demonstrating compliance with performance objectives are examined in this paper. The first approach uses the information obtained from the complex model to develop a simple model that mimics the complex model behavior for stated performance objectives. The simple model may need to include essential processes that are important to assessing performance, such as time-variable infiltration and waste emplacement rates, subsurface heterogeneity, sorption, decay, and radioactive ingrowth. The approach was applied to a Low-Level Waste disposal site at the Idaho National Laboratory where a complex three dimensional vadose zone model was developed first to understand system behavior and important processes. The complex model was distilled down to a relatively simple one-dimensional vadose zone model and three-dimensional aquifer transport model. Comparisons between the simple model and complex model of vadose zone fluxes and groundwater concentrations showed relatively good agreement between the models for both fission and activation products (129I, 36Cl, 99Tc) and actinides (238U, 239Pu, 237Np). Application of the simple model allowed for Monte Carlo uncertainty analysis and simulations of numerous disposal and release scenarios. The second approach investigated was the response surface model. In the response surface model approach

  14. EPR characteristics of free radicals in DOPA-melanin-moxifloxacin complexes at ambient level of UVA radiation

    NASA Astrophysics Data System (ADS)

    Beberok, Artur; Zdybel, Magdalena; Pilawa, Barbara; Buszman, Ewa; Wrześniok, Dorota

    2014-01-01

    EPR studies pointed out that o-semiquinone free radicals with g-values 2.0038-2.0040 take part in moxifloxacin-melanin complex formation. The process contributed to increase in free radicals concentration in nonirradiated complexes. This effect was observed for the complexes with 1 × 10-4 M, 1 × 10-3 M and 4 × 10-3 M drug concentrations. UV irradiation contributed to decrease in free radicals concentration in DOPA-melanin complexes with moxifloxacin, besides the complexes with the drug concentration of 1 × 10-4 M. The strongest decrease was observed for DOPA-melanin-moxifloxacin complexes with the drug concentration of 1 × 10-3 M. Homogeneous broadening of EPR lines, strong dipolar interactions and slow spin-lattice relaxation processes characterized all the tested melanin samples.

  15. Approximate method for calculating the radiation from a moving charge in the presence of a complex object.

    PubMed

    Belonogaya, Ekaterina S; Tyukhtin, Andrey V; Galyamin, Sergey N

    2013-04-01

    An approximate method for calculating the radiation from a moving charge in the presence of a dielectric object is developed. The method is composed of two steps. The first step is calculation of the field in the medium without considering the external boundaries of the object, and the second step is an approximate (ray-optical) calculation of the wave propagation outside the object. As a test problem, we consider the case of a charge crossing a dielectric plate. Computations of the field are performed using exact and approximate methods. It is shown that the results agree well. Additionally, we apply the method under consideration to the case of a cone-shaped object with a vacuum channel. The radiation energy spectral density as a function of the location of the observation point and the problem's parameters is given. In particular, the convergent radiation effect is described. PMID:23679539

  16. Molecular phylogenetics of the Espeletia complex (Asteraceae): evidence from nrDNA ITS sequences on the closest relatives of an Andean adaptive radiation.

    PubMed

    Rauscher, Jason T

    2002-07-01

    The subtribe Espeletiinae (Asteraceae, Heliantheae) comprises morphologically and ecologically diverse plants endemic to the tropical montane paramos of the Andes of Venezuela, Colombia, and Ecuador. Though the ecophysiology and ecology of this adaptive radiation have been well studied, relationships among taxa in the subtribe and between the subtribe and other taxa in the Heliantheae are poorly known. In this study, sequences from the internal transcribed spacer (ITS) region of nuclear ribosomal DNA are used to test previous hypotheses about the phylogenetic position of the Espeletiinae within the Heliantheae and to determine which taxa are the subtribe's closest relatives. Gene phylogenies based on maximum parsimony analyses reveal that the Espeletiinae clade is nested well within the subtribe Melampodiinae and thus should be considered a monophyletic complex of species, not a separate subtribe. The most parsimonious gene trees suggest that the genus Ichthyothere may be the sister taxon to the Espeletia complex and that the genus Smallanthus and a species of Rumfordia are likely among the complex's other closest living relatives. These data offer preliminary insights into the origins of this adaptive radiation and the broader phylogenetic context in which it occurred. PMID:21665707

  17. Theoretical Insights into the Photo-Deactivation of Emitting Triplet Excited State of (C^N)Pt(O^O) Complexes: Radiative and Nonradiative Decay Processes.

    PubMed

    Xu, Yanyan; Luo, Yafei; Li, Ming; He, Rongxing; Shen, Wei

    2016-09-01

    In this study, density functional theory (DFT) and time-dependent DFT were employed to elucidate the photo-deactivation mechanisms of (C^N)Pt(O^O) complexes 1-4 (where C^N = 2-phenylpyridine derivatives, O^O = dipivolylmethanoate). To make thorough understanding of the radiative decay, the singlet-triplet splitting energies ΔE(Sn-T1) (n = 1, 2, 3, 4, ...), transition dipole moment μ(Sn) for S0-Sn transitions and the spin-orbit coupling (SOC) matrix elements ⟨T1|HSOC|Sn⟩ were all calculated. Moreover, the spin-orbit coupling between T1 and S0 ⟨T1|HSOC|S0⟩ and Huang-Rhys factors were calculated to estimate the temperature-independent nonradiative decay processes. Meanwhile, the thermal deactivation via metal-centered (3)MC was described to analyze the temperature-dependent nonradiative decay processes. As a result, the effective SOC interaction between the lowest triplet and singlet excited states successfully rationalize why complexes 1 and 3 have higher radiative decay rate constant than that of complex 2, while the larger ⟨T1|HSOC|S0⟩ and lower energy barrier for thermal deactivation in 3 reasonably explains why 3 has larger nonradiative rate than that of 1 and 2. Consequently, it can be concluded that it is the ⟨T1|HSOC|S0⟩ and thermal population of (3)MC that account for the nonemissive behavior of (C^N)Pt(O^O) complexes, and controlling π-conjugation is an efficient method for tuning phosphorescence properties of transition-metal complexes. PMID:27517617

  18. Competitive inhibition of carcinogen-activating CYP1A1 and CYP1B1 enzymes by a standardized complex mixture of PAH extracted from coal tar

    SciTech Connect

    Mahadevan, B.; Marston, C.P.; Luch, A.; Dashwood, W.M.; Brooks, E.; Pereira, C.; Doehmer, J.; Baird, W.M.

    2007-03-15

    A complex mixture of polycyclic aromatic hydrocarbons (PAH) extracted from coal tar, the Standard Reference Material (SRM) 1597, was recently shown to decrease the levels of DNA binding of the 2 strong carcinogens benzo(a)pyrene (BP) and dibenzo(a,l)pyrene (DBP) in the human mammary carcinoma-derived cell line MCF-7. The present study was designed to further elucidate the biochemical mechanisms involved in this inhibition process. We examined the effects of SRM 1597 on the metabolic activation of BP and DBP toward DNA-binding derivatives in Chinese hamster cells expressing either human cytochrome P450 (CYP) 1A1 or CYP1B1. The data obtained from biochemical experiments revealed that SRM 1597 competitively inhibited the activity of both human enzymes as analyzed by 7-ethoxyresorufin O-deethylation assays. While the Michaelis-Menten constant (K-M) was {lt} 0.4 {mu}M in the absence of SRM 1597, this value increased up to 1.12 (CYP1A1) or 4.45 {mu}M (CYP1B1) in the presence of 0.1 {mu} g/ml SRM 1597. Hence the inhibitory effects of the complex mixture on human CYP1B1 were much stronger when compared to human CYP1A1 Taken together, the decreases in PAH-DNA adduct formation on co-treatment with SRM 1597 revealed inhibitory effects on the CYP enzymes that convert carcinogenic PAH into DNA-binding metabolites. The implications for the tumorigenicity of complex environmental PAR mixtures are discussed.

  19. Bcl2 inhibits recruitment of Mre11 complex to DNA double-strand breaks in response to high-linear energy transfer radiation.

    PubMed

    Xie, Maohua; Park, Dongkyoo; You, Shuo; Li, Rui; Owonikoko, Taofeek K; Wang, Ya; Doetsch, Paul W; Deng, Xingming

    2015-01-01

    High-linear energy transfer ionizing radiation, derived from high charge (Z) and energy (E) (HZE) particles, induces clustered/complex DNA double-strand breaks (DSBs) that include small DNA fragments, which are not repaired by the non-homologous end-joining (NHEJ) pathway. The homologous recombination (HR) DNA repair pathway plays a major role in repairing DSBs induced by HZE particles. The Mre11 complex (Mre11/Rad50/NBS1)-mediated resection of DSB ends is a required step in preparing for DSB repair via the HR DNA repair pathway. Here we found that expression of Bcl2 results in decreased HR activity and retards the repair of DSBs induced by HZE particles (i.e. (56)iron and (28)silicon) by inhibiting Mre11 complex activity. Exposure of cells to (56)iron or (28)silicon promotes Bcl2 to interact with Mre11 via the BH1 and BH4 domains. Purified Bcl2 protein directly suppresses Mre11 complex-mediated DNA resection in vitro. Expression of Bcl2 reduces the ability of Mre11 to bind DNA following exposure of cells to HZE particles. Our findings suggest that, after cellular exposure to HZE particles, Bcl2 may inhibit Mre11 complex-mediated DNA resection leading to suppression of the HR-mediated DSB repair in surviving cells, which may potentially contribute to tumor development. PMID:25567982

  20. Synthesis and structural characterization of dioxomolybdenum and dioxotungsten hydroxamato complexes and their function in the protection of radiation induced DNA damage.

    PubMed

    Paul, Shiv Shankar; Selim, Md; Saha, Abhijit; Mukherjea, Kalyan K

    2014-02-21

    The synthesis and structural characterization of two novel dioxomolybdenum(VI) (1) and dioxotungsten(VI) (2) complexes with 2-phenylacetylhydroxamic acid (PAHH) [M(O)2(PAH)2] [M = Mo, W] have been accomplished. The dioxomolybdenum(VI) and dioxotungsten(VI) moiety is coordinated by the hydroxamate group (-CONHO(-)) of the 2-phenylacetylhydroxamate (PAH) ligand in a bi-dentate fashion. In both the complexes the PAHH ligand is coordinated through oxygen atoms forming a five membered chelate. The hydrogen atom of N-H of the hydroxamate group is engaged in intermolecular H-bonding with the carbonyl oxygen of another coordinated hydroxamate ligand, thereby forming an extended 1D chain. The ligand as well as both the complexes exhibit the ability to protect from radiation induced damage both in CTDNA as well as in pUC19 plasmid DNA. As the damage to DNA is caused by the radicals generated during radiolysis, its scavenging imparts protection from the damage to DNA. To understand the mechanism of protection, binding affinities of the ligand and the complex with DNA were determined using absorption and emission spectral studies and viscosity measurements, whereby the results indicate that both the complexes and the hydroxamate ligand interact with calf thymus DNA in the minor groove. The intrinsic binding constants, obtained from UV-vis studies, are 7.2 × 10(3) M(-1), 5.2 × 10(4) M(-1) and 1.2 × 10(4) M(-1) for the ligand and complexes 1 and 2 respectively. The Stern-Volmer quenching constants obtained from a luminescence study for both the complexes are 5.6 × 10(4) M(-1) and 1.6 × 10(4) M(-1) respectively. The dioxomolybdenum(VI) complex is found to be a more potent radioprotector compared to the dioxotungsten(VI) complex and the ligand. Radical scavenging chemical studies suggest that the complexes have a greater ability to scavenge both the hydroxyl as well as the superoxide radicals compared to the ligand. The free radical scavenging ability of the ligand and the

  1. Comparative effectiveness of a complex Ayurvedic treatment and conventional standard care in osteoarthritis of the knee – study protocol for a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Traditional Indian Ayurvedic medicine uses complex treatment approaches, including manual therapies, lifestyle and nutritional advice, dietary supplements, medication, yoga, and purification techniques. Ayurvedic strategies are often used to treat osteoarthritis (OA) of the knee; however, no systematic data are available on their effectiveness in comparison with standard care. The aim of this study is to evaluate the effectiveness of complex Ayurvedic treatment in comparison with conventional methods of treating OA symptoms in patients with knee osteoarthritis. Methods and design In a prospective, multicenter, randomized controlled trial, 150 patients between 40 and 70 years, diagnosed with osteoarthritis of the knee, following American College of Rheumatology criteria and an average pain intensity of ≥40 mm on a 100 mm visual analog scale in the affected knee at baseline will be randomized into two groups. In the Ayurveda group, treatment will include tailored combinations of manual treatments, massages, dietary and lifestyle advice, consideration of selected foods, nutritional supplements, yoga posture advice, and knee massage. Patients in the conventional group will receive self-care advice, pain medication, weight-loss advice (if overweight), and physiotherapy following current international guidelines. Both groups will receive 15 treatment sessions over 12 weeks. Outcomes will be evaluated after 6 and 12 weeks and 6 and 12 months. The primary endpoint is a change in the score on the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) after 12 weeks. Secondary outcome measurements will use WOMAC subscales, a pain disability index, a visual analog scale for pain and sleep quality, a pain experience scale, a quality-of-life index, a profile of mood states, and Likert scales for patient satisfaction, patient diaries, and safety. Using an adapted PRECIS scale, the trial was identified as lying mainly in the middle of the efficacy

  2. LLL calibration and standards facility

    SciTech Connect

    Campbell, G.W.; Elliott, J.H.

    1980-04-15

    The capabilities of Lawrence Livermore Laboratory's Calibration and Standards Facility are delineated. The facility's ability to provide radiation fields and measurements for a variety of radiation safety applications and the available radiation measurement equipment are described. The need for national laboratory calibration labs to maintain traceability to a national standard are discussed as well as the areas where improved standards and standardization techniques are needed.

  3. KEY COMPARISON: COOMET.RI(I)-K1 comparison of national measurement standards of air kerma for 60Co γ radiation

    NASA Astrophysics Data System (ADS)

    Büermann, L.; Oborin, A. V.; Dobrovosky, J.; Milevsky, V. S.; Walwyn Salas, G.; Lapenas, A.

    2009-01-01

    Results are presented of the COOMET key comparison of the national measurement standards of air kerma for 60Co γ radiation. Participants of the comparison were PTB (Germany, pilot institute), VNIIM (Russia), SMU (Slovakia), BelGIM (Belarus), CPHR (Cuba) and RMTC (Latvia). PTB, VNIIM and SMU had previously taken part in a key comparison with the Bureau International de Poids et Mesures (BIPM) and operated as link laboratories in order to evaluate the degree of equivalence of the participants' results with the key comparison reference value. These data form the basis of the results entered into the BIPM key comparison database for comparison COOMET.RI(I)-K1. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI Section I, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  4. Searching the Inclusive Lepton + Photon + Missing E(T) + b-quark Signature for Radiative Top Quark Decay and Non-Standard-Model Processes

    SciTech Connect

    Aaltonen, T.; Adelman, Jahred A.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E.; Anastassov, A.; Annovi, Alberto; Antos, Jaroslav; Apollinari, G.; Apresyan, A.; /Purdue U. /Waseda U.

    2009-06-01

    In a search for new phenomena in a signature suppressed in the standard model of elementary particles (SM), we compare the inclusive production of events containing a lepton ({ell}), a photon ({gamma}), significant transverse momentum imbalance (E{sub T}), and a jet identified as containing a b-quark, to SM predictions. The search uses data produced in proton-antiproton collisions at {radical}s = 1.96 TeV corresponding to 1.9 fb{sup -1} of integrated luminosity taken with the CDF detector at the Fermilab Tevatron. We find 28 {ell}{gamma}bE{sub T} events versus an expectation of 31.0{sub -3.5}{sup +4.1} events. If we further require events to contain at least three jets and large total transverse energy, simulations predict that the largest SM source is top-quark pair production with an additional radiated photon, t{bar t} + {gamma}. In the data we observe 16 t{bar t}{gamma} candidate events versus an expectation from non-top-quark SM sources of 11.2{sub -2.1}{sup +2.3}. Assuming the difference between the observed number and the predicted non-top-quark total is due to SM top quark production, we estimate the t{bar t} cross section to be 0.15 {+-} 0.08 pb.

  5. Cytogenetic analysis of Epicauta atomaria (Meloidae) and Palembus dermestoides (Tenebrionidae) with Xyp sex determination system using standard staining, C-bands, NOR and synaptonemal complex microspreading techniques.

    PubMed

    De Almeida, M C; Zacaro, A A; Cella, D M

    2000-01-01

    The mitotic and meiotic chromosomes of the beetles Epicauta atomaria (Meloidae) and Palembus dermestoides (Tenebrionidae) were analysed using standard staining, C-banding and silver impregnation techniques. We determine the diploid and haploid chromosome numbers, the sex determination system and describe the chromosomal morphology, the C-banding pattern and the chromosome(s) bearing NORs (nucleolar organizer regions). Both species shown 2n = 20 chromosomes, the chromosomal meioformula 9 + Xyp, and regular chromosome segregation during anaphases I and II. The chromosomes of E. atomaria are basically metacentric or submetacentric and P. dermestoides chromosomes are submetacentric or subtelocentric. In both beetles the constitutive heterochromatin is located in the pericentromeric region in all autosomes and in the Xp chromosome; additional C-bands were observed in telomeric region of the short arm in some autosomes in P. dermestoides. The yp chromosome did not show typical C-bands in these species. As for the synaptonemal complex, the nucleolar material is associated to the 7th bivalent in E. atomaria and 3rd and 7th bivalents in P. dermestoides. Strong silver impregnated material was observed in association with Xyp in light and electron microscopy preparations in these species and this material was interpreted to be related to nucleolar material. PMID:11338427

  6. THE COMPLEXITY THAT THE FIRST STARS BROUGHT TO THE UNIVERSE: FRAGILITY OF METAL-ENRICHED GAS IN A RADIATION FIELD

    SciTech Connect

    Aykutalp, A.; Spaans, M. E-mail: spaans@astro.rug.nl

    2011-08-20

    The initial mass function (IMF) of the first (Population III) stars and Population II (Pop II) stars is poorly known due to a lack of observations of the period between recombination and reionization. In simulations of the formation of the first stars, it has been shown that, due to the limited ability of metal-free primordial gas to cool, the IMF of the first stars is a few orders of magnitude more massive than the current IMF. The transition from a high-mass IMF of the first stars to a lower-mass current IMF is thus important to understand. To study the underlying physics of this transition, we performed several simulations using the cosmological hydrodynamic adaptive mesh refinement code Enzo for metallicities of 10{sup -4}, 10{sup -3}, 10{sup -2}, and 10{sup -1} Z{sub sun}. In our simulations, we include a star formation prescription that is derived from a metallicity-dependent multi-phase interstellar medium (ISM) structure, an external UV radiation field, and a mechanical feedback algorithm. We also implement cosmic ray heating, photoelectric heating, and gas-dust heating/cooling, and follow the metal enrichment of the ISM. It is found that the interplay between metallicity and UV radiation leads to the coexistence of Pop III and Pop II star formation in non-zero-metallicity (Z/Z{sub sun} {>=} 10{sup -2}) gas. A cold (T < 100 K) and dense ({rho} > 10{sup -22} g cm{sup -3}) gas phase is fragile to ambient UV radiation. In a metal-poor (Z/Z{sub sun} {<=} 10{sup -3}) gas, the cold and dense gas phase does not form in the presence of a radiation field of F{sub 0} {approx} 10{sup -5}-10{sup -4} erg cm{sup -2} s{sup -1}. Therefore, metallicity by itself is not a good indicator of the Pop III-Pop II transition. Metal-rich (Z/Z{sub sun} {>=} 10{sup -2}) gas dynamically evolves two to three orders of magnitude faster than metal-poor gas (Z/Z{sub sun} {<=} 10{sup -3}). The simulations including supernova explosions show that pre-enrichment of the halo does not affect

  7. The search for gamma radiation from supernova 1987A in an experiment aboard the Salut-7/Cosmos-1686 complex

    NASA Astrophysics Data System (ADS)

    Bachilova, R. N.; Bloch, G. M.; Pankov, V. M.; Prohin, V. L.; Rutkovsky, A. I.; Rumin, S. P.

    1988-07-01

    Gamma-quanta flux measurements were carried out during February-October 1987 in a search for radiation from SN 1987A. The time dependence of the mean monthly gamma-quanta flux measured with the Nega telescope at an altitude of 500 km in the equatorial region is analyzed. The upper limit of the gamma-quanta flux is determined to be 1.5 x 10 to the -6th/sq cm s keV on the 3-sigma level for the 1.5-4.4 MeV energy interval.

  8. BRCA1-BARD1 complexes are required for p53Ser-15 phosphorylation and a G1/S arrest following ionizing radiation-induced DNA damage.

    PubMed

    Fabbro, Megan; Savage, Kienan; Hobson, Karen; Deans, Andrew J; Powell, Simon N; McArthur, Grant A; Khanna, Kum Kum

    2004-07-23

    BRCA1 is a major player in the DNA damage response. This is evident from its loss, which causes cells to become sensitive to a wide variety of DNA damaging agents. The major BRCA1 binding partner, BARD1, is also implicated in the DNA damage response, and recent reports indicate that BRCA1 and BARD1 co-operate in this pathway. In this report, we utilized small interfering RNA to deplete BRCA1 and BARD1 to demonstrate that the BRCA1-BARD1 complex is required for ATM/ATR (ataxia-telangiectasia-mutated/ATM and Rad3-related)-mediated phosphorylation of p53(Ser-15) following IR- and UV radiation-induced DNA damage. In contrast, phosphorylation of a number of other ATM/ATR targets including H2AX, Chk2, Chk1, and c-jun does not depend on the presence of BRCA1-BARD1 complexes. Moreover, prior ATM/ATR-dependent phosphorylation of BRCA1 at Ser-1423 or Ser-1524 regulates the ability of ATM/ATR to phosphorylate p53(Ser-15) efficiently. Phosphorylation of p53(Ser-15) is necessary for an IR-induced G(1)/S arrest via transcriptional induction of the cyclin-dependent kinase inhibitor p21. Consistent with these data, repressing p53(Ser-15) phosphorylation by BRCA1-BARD1 depletion compromises p21 induction and the G(1)/S checkpoint arrest in response to IR but not UV radia-tion. These findings suggest that BRCA1-BARD1 complexes act as an adaptor to mediate ATM/ATR-directed phosphorylation of p53, influencing G(1)/S cell cycle progression after DNA damage. PMID:15159397

  9. Clinical quality standards for radiotherapy

    PubMed Central

    2012-01-01

    Aim of the study The technological progress that is currently being witnessed in the areas of diagnostic imaging, treatment planning systems and therapeutic equipment has caused radiotherapy to become a high-tech and interdisciplinary domain involving staff of various backgrounds. This allows steady improvement in therapy results, but at the same time makes the diagnostic, imaging and therapeutic processes more complex and complicated, requiring every stage of those processes to be planned, organized, controlled and improved so as to assure high quality of services provided. The aim of this paper is to present clinical quality standards for radiotherapy as developed by the author. Material and methods In order to develop the quality standards, a comparative analysis was performed between European and Polish legal acts adopted in the period of 1980-2006 and the universal industrial ISO 9001:2008 standard, defining requirements for quality management systems, and relevant articles published in 1984-2009 were reviewed, including applicable guidelines and recommendations of American, international, European and Polish bodies, such as the American Association of Physicists in Medicine (AAPM), the European Society for Radiotherapy & Oncology (ESTRO), the International Atomic Energy Agency (IAEA), and the Organisation of European Cancer Institutes (OECI) on quality assurance and management in radiotherapy. Results As a result, 352 quality standards for radiotherapy were developed and categorized into the following three groups: 1 – organizational standards; 2 – physico-technical standards and 3 – clinical standards. Conclusion Proposed clinical quality standards for radiotherapy can be used by any institution using ionizing radiation for medical purposes. However, standards are of value only if they are implemented, reviewed, audited and improved, and if there is a clear mechanism in place to monitor and address failure to meet agreed standards. PMID:23788854

  10. Analysis of rapidly synthesized guest-filled porous complexes with synchrotron radiation: practical guidelines for the crystalline sponge method

    SciTech Connect

    Ramadhar, Timothy R.; Zheng, Shao-Liang; Chen, Yu-Sheng

    2015-01-01

    This report describes complete practical guidelines and insights for the crystalline sponge method, which have been derived through the first use of synchrotron radiation on these systems, and includes a procedure for faster synthesis of the sponges. These guidelines will be applicable to crystal sponge data collected at synchrotrons or in-house facilities, and will allow researchers to obtain reliable high-quality data and construct chemically and physically sensible models for guest structural determination. A detailed set of synthetic and crystallographic guidelines for the crystalline sponge method based upon the analysis of expediently synthesized crystal sponges using third-generation synchrotron radiation are reported. The procedure for the synthesis of the zinc-based metal–organic framework used in initial crystal sponge reports has been modified to yield competent crystals in 3 days instead of 2 weeks. These crystal sponges were tested on some small molecules, with two being unexpectedly difficult cases for analysis with in-house diffractometers in regard to data quality and proper space-group determination. These issues were easily resolved by the use of synchrotron radiation using data-collection times of less than an hour. One of these guests induced a single-crystal-to-single-crystal transformation to create a larger unit cell with over 500 non-H atoms in the asymmetric unit. This led to a non-trivial refinement scenario that afforded the best Flack x absolute stereochemical determination parameter to date for these systems. The structures did not require the use of PLATON/SQUEEZE or other solvent-masking programs, and are the highest-quality crystalline sponge systems reported to date where the results are strongly supported by the data. A set of guidelines for the entire crystallographic process were developed through these studies. In particular, the refinement guidelines include strategies to refine the host framework, locate guests and determine

  11. Silencing of miR-21 by locked nucleic acid-lipid nanocapsule complexes sensitize human glioblastoma cells to radiation-induced cell death.

    PubMed

    Griveau, A; Bejaud, J; Anthiya, S; Avril, S; Autret, D; Garcion, E

    2013-10-01

    The recent discovery of microRNA (miRNA) as major post-transcriptional repressors prompt the interest of developing novel approaches to target miRNA pathways to improve therapy. In this context, although the most significant barrier to their widespread clinical use remains delivery, nuclease-resistant locked nucleic acid (LNA) that bind specifically and irreversibly to miRNA represent interesting weapons. Thus, by focusing on oncongenic miR-21 miRNA, which participate to cancer cell resistance to apoptotic signals, the aim of the present study was to investigate the possibility of silencing miRNA by LNA conjugated to lipid nanocapsules (LNCs) as miRNA-targeted nanomedicines in U87MG glioblastoma (GBM) cells. After synthesis of an amphiphilic lipopeptide affine for nucleic acids, a post-insertion procedure during the LNC phase inversion formulation process allowed to construct peptide-conjugated LNCs. Peptide-conjugated LNCs were then incubated with LNAs to allow the formation of complexes characterized in gel retardation assays and by their physicochemical properties. U87MG cell treatment by LNA-LNC complexes resulted in a marked reduction of miR-21 expression as assessed by RTqPCR. In addition, exposure of U87MG cells to LNA-LNC complexes followed by external beam radiation demonstrated a significant improvement of cell sensitivity to treatment and emphasizes the interest to investigate further this miRNA-targeted strategy. PMID:23732394

  12. Randomized Noninferiority Trial of Reduced High-Dose Volume Versus Standard Volume Radiation Therapy for Muscle-Invasive Bladder Cancer: Results of the BC2001 Trial (CRUK/01/004)

    SciTech Connect

    Huddart, Robert A.; Hall, Emma; Hussain, Syed A.; Jenkins, Peter; Rawlings, Christine; Tremlett, Jean; Crundwell, Malcolm; Adab, Fawzi A.; Sheehan, Denise; Syndikus, Isabel; Hendron, Carey; Lewis, Rebecca; Waters, Rachel; James, Nicholas D.

    2013-10-01

    Purpose: To test whether reducing radiation dose to uninvolved bladder while maintaining dose to the tumor would reduce side effects without impairing local control in the treatment of muscle-invasive bladder cancer. Methods and Materials: In this phase III multicenter trial, 219 patients were randomized to standard whole-bladder radiation therapy (sRT) or reduced high-dose volume radiation therapy (RHDVRT) that aimed to deliver full radiation dose to the tumor and 80% of maximum dose to the uninvolved bladder. Participants were also randomly assigned to receive radiation therapy alone or radiation therapy plus chemotherapy in a partial 2 × 2 factorial design. The primary endpoints for the radiation therapy volume comparison were late toxicity and time to locoregional recurrence (with a noninferiority margin of 10% at 2 years). Results: Overall incidence of late toxicity was less than predicted, with a cumulative 2-year Radiation Therapy Oncology Group grade 3/4 toxicity rate of 13% (95% confidence interval 8%, 20%) and no statistically significant differences between groups. The difference in 2-year locoregional recurrence free rate (RHDVRT − sRT) was 6.4% (95% confidence interval −7.3%, 16.8%) under an intention to treat analysis and 2.6% (−12.8%, 14.6%) in the “per-protocol” population. Conclusions: In this study RHDVRT did not result in a statistically significant reduction in late side effects compared with sRT, and noninferiority of locoregional control could not be concluded formally. However, overall low rates of clinically significant toxicity combined with low rates of invasive bladder cancer relapse confirm that (chemo)radiation therapy is a valid option for the treatment of muscle-invasive bladder cancer.

  13. Analysis of rapidly synthesized guest-filled porous complexes with synchrotron radiation: Practical guidelines for the crystalline sponge method

    DOE PAGESBeta

    Ramadhar, Timothy R.; Zheng, Shao -Liang; Chen, Yu -Sheng; Clardy, Jon

    2015-01-01

    A detailed set of synthetic and crystallographic guidelines for the crystalline sponge method based upon the analysis of expediently synthesized crystal sponges using third-generation synchrotron radiation are reported. The procedure for the synthesis of the zinc-based metal–organic framework used in initial crystal sponge reports has been modified to yield competent crystals in 3 days instead of 2 weeks. These crystal sponges were tested on some small molecules, with two being unexpectedly difficult cases for analysis with in-house diffractometers in regard to data quality and proper space-group determination. These issues were easily resolved by the use of synchrotron radiation using data-collectionmore » times of less than an hour. One of these guests induced a single-crystal-to-single-crystal transformation to create a larger unit cell with over 500 non-H atoms in the asymmetric unit. This led to a non-trivial refinement scenario that afforded the best Flack x absolute stereochemical determination parameter to date for these systems. The structures did not require the use of PLATON/SQUEEZE or other solvent-masking programs, and are the highest-quality crystalline sponge systems reported to date where the results are strongly supported by the data. A set of guidelines for the entire crystallographic process were developed through these studies. In particular, the refinement guidelines include strategies to refine the host framework, locate guests and determine occupancies, discussion of the proper use of geometric and anisotropic displacement parameter restraints and constraints, and whether to perform solvent squeezing/masking. The single-crystal-to-single-crystal transformation process for the crystal sponges is also discussed. The presented general guidelines will be invaluable for researchers interested in using the crystalline sponge method at in-house diffraction or synchrotron facilities, will facilitate the collection and analysis of reliable high

  14. Analysis of rapidly synthesized guest-filled porous complexes with synchrotron radiation: Practical guidelines for the crystalline sponge method

    SciTech Connect

    Ramadhar, Timothy R.; Zheng, Shao -Liang; Chen, Yu -Sheng; Clardy, Jon

    2015-01-01

    A detailed set of synthetic and crystallographic guidelines for the crystalline sponge method based upon the analysis of expediently synthesized crystal sponges using third-generation synchrotron radiation are reported. The procedure for the synthesis of the zinc-based metal–organic framework used in initial crystal sponge reports has been modified to yield competent crystals in 3 days instead of 2 weeks. These crystal sponges were tested on some small molecules, with two being unexpectedly difficult cases for analysis with in-house diffractometers in regard to data quality and proper space-group determination. These issues were easily resolved by the use of synchrotron radiation using data-collection times of less than an hour. One of these guests induced a single-crystal-to-single-crystal transformation to create a larger unit cell with over 500 non-H atoms in the asymmetric unit. This led to a non-trivial refinement scenario that afforded the best Flack x absolute stereochemical determination parameter to date for these systems. The structures did not require the use of PLATON/SQUEEZE or other solvent-masking programs, and are the highest-quality crystalline sponge systems reported to date where the results are strongly supported by the data. A set of guidelines for the entire crystallographic process were developed through these studies. In particular, the refinement guidelines include strategies to refine the host framework, locate guests and determine occupancies, discussion of the proper use of geometric and anisotropic displacement parameter restraints and constraints, and whether to perform solvent squeezing/masking. The single-crystal-to-single-crystal transformation process for the crystal sponges is also discussed. The presented general guidelines will be invaluable for researchers interested in using the crystalline sponge method at in-house diffraction or synchrotron facilities, will facilitate the collection and analysis of

  15. Toxicity of cobalt-complexed cyanide to Oncorhynchus mykiss, Daphnia magna, and Ceriodaphnia dubia: Potentiation by ultraviolet radiation and attenuation by dissolved organic carbon and adaptive UV tolerance

    USGS Publications Warehouse

    Little, E.E.; Calfee, R.D.; Theodorakos, P.; Brown, Z.A.; Johnson, C.A.

    2007-01-01

    Background. Cobalt cyanide complexes often result when ore is treated with cyanide solutions to extract gold and other metals. These have recently been discovered in low but significant concentrations in effluents from gold leach operations. This study was conducted to determine the potential toxicity of cobalt-cyanide complexes to freshwater organisms and the extent to which ultraviolet radiation (UV) potentiates this toxicity. Tests were also conducted to determine if humic acids or if adaptation to UV influenced sensitivity to the cyanide complexes. Methods. Rainbow trout (Oncorhynchus mykiss), Daphnia magna, and Ceriodaphnia dubia were exposed to potassium hexacyanocobaltate in the presence and absence of UV radiation, in the presence and absence of humic acids. Cyano-cobalt exposures were also conducted with C. dubia from cultures adapted to elevated UV. Results. With an LC50 concentration of 0.38 mg/L, cyanocobalt was over a 1000 times more toxic to rainbow trout in the presence of UV at a low, environmentally relevant irradiance level (4 ??W/cm2 as UVB) than exposure to this compound in the absence of UV with an LC50 of 112.9 mg/L. Toxicity was immediately apparent, with mortality occurring within an hour of the onset of exposure at the highest concentration. Fish were unaffected by exposure to UV alone. Weak-acid dissociable cyanide concentrations were observed in irradiated aqueous solutions of cyanocobaltate within hours of UV exposure and persisted in the presence of UV for at least 96 hours, whereas negligible concentrations were observed in the absence of UV. The presence of humic acids significantly diminished cyanocobalt toxicity to D. magna and reduced mortality from UV exposure. Humic acids did not significantly influence survival among C. dubia. C. dubia from UV-adapted populations were less sensitive to metallocyanide compounds than organisms from unadapted populations. Conclusions. The results indicate that metallocyanide complexes may pose a

  16. Time-resolved radiation chemistry: Dynamics of electron attachment to uracil following UV excitation of iodide-uracil complexes

    SciTech Connect

    King, Sarah B.; Yandell, Margaret A.; Stephansen, Anne B.; Neumark, Daniel M.

    2014-12-14

    Electron attachment to uracil was investigated by applying time-resolved photoelectron imaging to iodide-uracil (I{sup –}U) complexes. In these studies, an ultraviolet pump pulse initiated charge transfer from the iodide to the uracil, and the resulting dynamics of the uracil temporary negative ion were probed. Five different excitation energies were used, 4.00 eV, 4.07 eV, 4.14 eV, 4.21 eV, and 4.66 eV. At the four lowest excitation energies, which lie near the vertical detachment energy of the I{sup –}U complex (4.11 eV), signatures of both the dipole bound (DB) as well as the valence bound (VB) anion of uracil were observed. In contrast, only the VB anion was observed at 4.66 eV, in agreement with previous experiments in this higher energy range. The early-time dynamics of both states were highly excitation energy dependent. The rise time of the DB anion signal was ∼250 fs at 4.00 eV and 4.07 eV, ∼120 fs at 4.14 eV and cross-correlation limited at 4.21 eV. The VB anion rise time also changed with excitation energy, ranging from 200 to 300 fs for excitation energies 4.00–4.21 eV, to a cross-correlation limited time at 4.66 eV. The results suggest that the DB state acts as a “doorway” state to the VB anion at 4.00–4.21 eV, while direct attachment to the VB anion occurs at 4.66 eV.

  17. Randomized, Multicenter Trial on the Effect of Radiation Therapy on Plantar Fasciitis (Painful Heel Spur) Comparing a Standard Dose With a Very Low Dose: Mature Results After 12 Months' Follow-Up

    SciTech Connect

    Niewald, Marcus; Micke, Oliver; Graeber, Stefan; Schaefer, Vera; Scheid, Christine; Fleckenstein, Jochen; Licht, Norbert; Ruebe, Christian

    2012-11-15

    Purpose: To conduct a randomized trial of radiation therapy for painful heel spur, comparing a standard dose with a very low dose. Methods and Materials: Sixty-six patients were randomized to receive radiation therapy either with a total dose of 6.0 Gy applied in 6 fractions of 1.0 Gy twice weekly (standard dose) or with a total dose of 0.6 Gy applied in 6 fractions of 0.1 Gy twice weekly (low dose). In all patients lateral opposing 4- to 6-MV photon beams were used. The results were measured using a visual analogue scale, the Calcaneodynia score, and the SF12 health survey. The fundamental phase of the study ended after 3 months, and the follow-up was continued up to 1 year. Patients with insufficient pain relief after 3 months were offered reirradiation with the standard dosage at any time afterward. Results: Of 66 patients, 4 were excluded because of withdrawal of consent or screening failures. After 3 months the results in the standard arm were highly significantly superior compared with those in the low-dose arm (visual analogue scale, P=.001; Calcaneodynia score, P=.027; SF12, P=.045). The accrual of patients was stopped at this point. Further evaluation after 12 months' follow-up showed the following results: (1) highly significant fewer patients were reirradiated in the standard arm compared with the low-dose arm (P<.001); (2) the results of patients in the low-dose arm who were reirradiated were identical to those in the standard arm not reirradiated (reirradiation as a salvage therapy if the lower dose was ineffective); (3) patients experiencing a favorable result after 3 months showed this even after 12 months, and some results even improved further between 3 and 12 months. Conclusions: This study confirms the superior analgesic effect of radiation therapy with 6-Gy doses on painful heel spur even for a longer time period of at least 1 year.

  18. REACTIVE DESORPTION AND RADIATIVE ASSOCIATION AS POSSIBLE DRIVERS OF COMPLEX MOLECULE FORMATION IN THE COLD INTERSTELLAR MEDIUM

    SciTech Connect

    Vasyunin, A. I.; Herbst, Eric E-mail: eh2ef@virginia.edu

    2013-05-20

    The recent discovery of terrestrial-type organic species such as methyl formate and dimethyl ether in the cold interstellar gas has proved that the formation of organic matter in the Galaxy begins at a much earlier stage of star formation than was previously thought. This discovery represents a challenge for astrochemical modelers. The abundances of these molecules cannot be explained by the previously developed ''warm-up'' scenario, in which organic molecules are formed via diffusive chemistry on surfaces of interstellar grains starting at 30 K, and then released to the gas at higher temperatures during later stages of star formation. In this article, we investigate an alternative scenario in which complex organic species are formed via a sequence of gas-phase reactions between precursor species formed on grain surfaces and then ejected into the gas via efficient reactive desorption, a process in which non-thermal desorption occurs as a result of conversion of the exothermicity of chemical reactions into the ejection of products from the surface. The proposed scenario leads to reasonable if somewhat mixed results at temperatures as low as 10 K and may be considered as a step toward the explanation of abundances of terrestrial-like organic species observed during the earliest stages of star formation.

  19. Phylogeography of the Indo-West Pacific maskrays (Dasyatidae, Neotrygon): a complex example of chondrichthyan radiation in the Cenozoic

    PubMed Central

    Puckridge, Melody; Last, Peter R; White, William T; Andreakis, Nikos

    2013-01-01

    Maskrays of the genus Neotrygon (Dasyatidae) have dispersed widely in the Indo-West Pacific being represented largely by an assemblage of narrow-ranging coastal endemics. Phylogenetic reconstruction methods reproduced nearly identical and statistically robust topologies supporting the monophyly of the genus Neotrygon within the family Dasyatidae, the genus Taeniura being consistently basal to Neotrygon, and Dasyatis being polyphyletic to the genera Taeniurops and Pteroplatytrygon. The Neotrygon kuhlii complex, once considered to be an assemblage of color variants of the same biological species, is the most derived and widely dispersed subgroup of the genus. Mitochondrial (COI, 16S) and nuclear (RAG1) phylogenies used in synergy with molecular dating identified paleoclimatic fluctuations responsible for periods of vicariance and dispersal promoting population fragmentation and speciation in Neotrygon. Signatures of population differentiation exist in N. ningalooensis and N. annotata, yet a large-scale geological event, such as the collision between the Australian and Eurasian Plates, coupled with subsequent sea-level falls, appears to have separated a once homogeneous population of the ancestral form of N. kuhlii into southern Indian Ocean and northern Pacific taxa some 4–16 million years ago. Repeated climatic oscillations, and the subsequent establishment of land and shallow sea connections within and between Australia and parts of the Indo-Malay Archipelago, have both promoted speciation and established zones of secondary contact within the Indian and Pacific Ocean basins. PMID:23467194

  20. Proposed Reference Spectral Irradiance Standards to Improve Photovoltaic Concentrating System Design and Performance Evaluation: Preprint

    SciTech Connect

    Myers, D. R.; Emery, K. E.; Gueymard, C.

    2002-05-01

    This conference paper describes the American Society for Testing and Materials (ASTM), the International Electrotechnical Commission (IEC), and the International Standards Organization (ISO) standard solar terrestrial spectra (ASTM G-159, IEC-904-3, ISO 9845-1) provide standard spectra for photovoltaic performance applications. Modern terrestrial spectral radiation models and knowledge of atmospheric physics are applied to develop suggested revisions to update the reference spectra. We use a moderately complex radiative transfer model (SMARTS2) to produce the revised spectra. SMARTS2 has been validated against the complex MODTRAN radiative transfer code and spectral measurements. The model is proposed as an adjunct standard to reproduce the reference spectra. The proposed spectra represent typical clear sky spectral conditions associated with sites representing reasonable photovoltaic energy production and weathering and durability climates. The proposed spectra are under consideration by ASTM.

  1. Standardization versus Standards.

    ERIC Educational Resources Information Center

    Meier, Deborah

    2002-01-01

    Examines differences between old state-designed norm-referenced tests and new tests aligned with the curriculum. Concludes that new state tests are very similar to old ones. Discusses impact of new high-stakes standardized tests on students and teachers. Argues the new wave of standardized testing is not the answer to improving student…

  2. Plume radiation

    NASA Astrophysics Data System (ADS)

    Dirscherl, R.

    1993-06-01

    The electromagnetic radiation originating from the exhaust plume of tactical missile motors is of outstanding importance for military system designers. Both missile- and countermeasure engineer rely on the knowledge of plume radiation properties, be it for guidance/interference control or for passive detection of adversary missiles. To allow access to plume radiation properties, they are characterized with respect to the radiation producing mechanisms like afterburning, its chemical constituents, and reactions as well as particle radiation. A classification of plume spectral emissivity regions is given due to the constraints imposed by available sensor technology and atmospheric propagation windows. Additionally assessment methods are presented that allow a common and general grouping of rocket motor properties into various categories. These methods describe state of the art experimental evaluation techniques as well as calculation codes that are most commonly used by developers of NATO countries. Dominant aspects influencing plume radiation are discussed and a standardized test technique is proposed for the assessment of plume radiation properties that include prediction procedures. These recommendations on terminology and assessment methods should be common to all employers of plume radiation. Special emphasis is put on the omnipresent need for self-protection by the passive detection of plume radiation in the ultraviolet (UV) and infrared (IR) spectral band.

  3. Standards not that standard.

    PubMed

    Vilanova, Cristina; Tanner, Kristie; Dorado-Morales, Pedro; Villaescusa, Paula; Chugani, Divya; Frías, Alba; Segredo, Ernesto; Molero, Xavier; Fritschi, Marco; Morales, Lucas; Ramón, Daniel; Peña, Carlos; Peretó, Juli; Porcar, Manuel

    2015-01-01

    There is a general assent on the key role of standards in Synthetic Biology. In two consecutive letters to this journal, suggestions on the assembly methods for the Registry of standard biological parts have been described. We fully agree with those authors on the need of a more flexible building strategy and we highlight in the present work two major functional challenges standardization efforts have to deal with: the need of both universal and orthogonal behaviors. We provide experimental data that clearly indicate that such engineering requirements should not be taken for granted in Synthetic Biology. PMID:26435739

  4. Effect of Brain Stem and Dorsal Vagus Complex Dosimetry on Nausea and Vomiting in Head and Neck Intensity-Modulated Radiation Therapy

    SciTech Connect

    Ciura, Katherine; McBurney, Michelle; Nguyen, Baongoc; Pham, Mary; Rebueno, Neal; Fuller, Clifton D.; Guha-Thakurta, Nandita; Rosenthal, David I.

    2011-04-01

    Intensity-modulated radiation therapy (IMRT) is becoming the treatment of choice for many head and neck cancer patients. IMRT reduces some toxicities by reducing radiation dose to uninvolved normal tissue near tumor targets; however, other tissues not irradiated using previous 3D techniques may receive clinically significant doses, causing undesirable side effects including nausea and vomiting (NV). Irradiation of the brainstem, and more specifically, the area postrema and dorsal vagal complex (DVC), has been linked to NV. We previously reported preliminary hypothesis-generating dose effects associated with NV in IMRT patients. The goal of this study is to relate brainstem dose to NV symptoms. We retrospectively studied 100 consecutive patients that were treated for oropharyngeal cancer with IMRT. We contoured the brainstem, area postrema, and DVC with the assistance of an expert diagnostic neuroradiologist. We correlated dosimetry for the 3 areas contoured with weekly NV rates during IMRT. NV rates were significantly higher for patients who received concurrent chemotherapy. Post hoc analysis demonstrated that chemoradiation cases exhibited a trend towards the same dose-response relationship with both brainstem mean dose (p = 0.0025) and area postrema mean dose (p = 0.004); however, both failed to meet statistical significance at the p {<=} 0.002 level. Duration of toxicity was also greater for chemoradiation patients, who averaged 3.3 weeks with reported Common Terminology Criteria for Adverse Events (CTC-AE), compared with an average of 2 weeks for definitive RT patients (p = 0.002). For definitive RT cases, no dose-response trend could be ascertained. The mean brainstem dose emerged as a key parameter of interest; however, no one dose parameter (mean/median/EUD) best correlated with NV. This study does not address extraneous factors that would affect NV incidence, including the use of antiemetics, nor chemotherapy dose schedule specifics before and during RT. A

  5. Report on Performance Standards in Mathematics and English: Results from the New Standards Project, Big Sky Scoring Conference. Project 2.3: Complex Performance Assessments: Expanding the Scope and Approaches to Assessment.

    ERIC Educational Resources Information Center

    Resnick, Lauren; And Others

    The New Standards Project (NSP) is an effort to create a state- and district-based assessment and professional development system to serve as a catalyst for major educational reform. As part of a professional development strategy tied to assessment, 114 teachers, curriculum supervisors, and assessment directors, representing 23 states and…

  6. Radiation Nanomedicine for EGFR-Positive Breast Cancer: Panitumumab-Modified Gold Nanoparticles Complexed to the β-Particle-Emitter, (177)Lu.

    PubMed

    Yook, Simmyung; Cai, Zhongli; Lu, Yijie; Winnik, Mitchell A; Pignol, Jean-Philippe; Reilly, Raymond M

    2015-11-01

    Our objective was to construct a novel radiation nanomedicine for treatment of breast cancer (BC) expressing epidermal growth factor receptors (EGFR), particularly triple-negative tumors (TNBC). Gold nanoparticles (AuNP; 30 nm) were modified with polyethylene glycol (PEG) chains (4 kDa) derivatized with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelators for complexing the β-emitter, (177)Lu and with PEG chains (5 kDa) linked to panitumumab for targeting BC cells expressing EGFR. The AuNP were further coated with PEG chains (2 kDa) to stabilize the particles to aggregation. The binding and internalization of EGFR-targeted AuNP ((177)Lu-T-AuNP) into BC cells was studied and compared to nontargeted (177)Lu-NT-AuNP. The cytotoxicity of (177)Lu-T-AuNP and (177)Lu-NT-AuNP was measured in clonogenic assays using BC cells with widely different EGFR densities: MDA-MB-468 (10(6) receptors/cell), MDA-MB-231 (10(5) receptors/cell), and MCF-7 cells (10(4) receptors/cell). Radiation absorbed doses to the cell nucleus of MDA-MB-468 cells were estimated based on subcellular distribution. Darkfield and fluorescence microscopy as well as radioligand binding assays revealed that (177)Lu-T-AuNP were specifically bound by BC cells dependent on their EGFR density whereas the binding and internalization of (177)Lu-NT-AuNP was significantly lower. The affinity of binding of (177)Lu-T-AuNP to MDA-MB-468 cells was reduced by 2-fold compared to (123)I-labeled panitumumab (KD = 1.3 ± 0.2 nM vs 0.7 ± 0.4 nM, respectively). The cytotoxicity of (177)Lu-T-AuNP was dependent on the amount of radioactivity incubated with BC cells, their EGFR density and the radiosensitivity of the cells. The clonogenic survival (CS) of MDA-MB-468 cells overexpressing EGFR was reduced to <0.001% at the highest amount of (177)Lu-T-AuNP tested (4.5 MBq; 6 × 10(11) AuNP per 2.5 × 10(4)-1.2 × 10(5) cells). (177)Lu-T-AuNP were less effective for killing MDA-MB-231 cells or MCF-7 cells with

  7. How Much Confidence Can We Have in EU-SILC? Complex Sample Designs and the Standard Error of the Europe 2020 Poverty Indicators

    ERIC Educational Resources Information Center

    Goedeme, Tim

    2013-01-01

    If estimates are based on samples, they should be accompanied by appropriate standard errors and confidence intervals. This is true for scientific research in general, and is even more important if estimates are used to inform and evaluate policy measures such as those aimed at attaining the Europe 2020 poverty reduction target. In this article I…

  8. Consumption of the Soluble Dietary Fibre Complex PolyGlycopleX® Reduces Glycaemia and Increases Satiety of a Standard Meal Postprandially

    PubMed Central

    Solah, Vicky A.; O’Mara-Wallace, Babette; Meng, Xingqiong; Gahler, Roland J.; Kerr, Deborah A.; James, Anthony P.; Fenton, Haelee K.; Johnson, Stuart K.; Wood, Simon

    2016-01-01

    The effect of consumption of PolyGlycopleX® (PGX®) was compared to wheat dextrin (WD) in combination with a standard meal, on postprandial satiety and glycaemia in a double-blind, randomised crossover trial, of 14 healthy subjects trained as a satiety panel. At each of six two-hour satiety sessions, subjects consumed one of three different test meals on two separate occasions. The test meals were: a standard meal plus 5 g PGX; a standard meal plus 4.5 g of PGX as softgels; and a standard meal plus 5 g of WD. Subjects recorded fullness using a labelled magnitude scale at 0, 15, 30, 45, 60, 90, and 120 min and the total area under the curve (AUC), mean fullness vs. time was calculated. The meals with PGX (in granular and softgel form) gave higher satiety (AUC) (477 ± 121 and 454 ± 242 cm·min), than the meal with WD (215 ± 261 cm·min) (p < 0.001). Subjects had blood glucose levels measured after the meals with PGX (granules) and WD. Glucose response (AUC) was significantly lower (p < 0.001) after the PGX meal than for the WD meal.  The high viscosity reported for PGX is a likely mechanism behind the significant satiety and blood glucose modulating effects observed in this study. PMID:27164135

  9. Consumption of the Soluble Dietary Fibre Complex PolyGlycopleX(®) Reduces Glycaemia and Increases Satiety of a Standard Meal Postprandially.

    PubMed

    Solah, Vicky A; O'Mara-Wallace, Babette; Meng, Xingqiong; Gahler, Roland J; Kerr, Deborah A; James, Anthony P; Fenton, Haelee K; Johnson, Stuart K; Wood, Simon

    2016-01-01

    The effect of consumption of PolyGlycopleX(®) (PGX(®)) was compared to wheat dextrin (WD) in combination with a standard meal, on postprandial satiety and glycaemia in a double-blind, randomised crossover trial, of 14 healthy subjects trained as a satiety panel. At each of six two-hour satiety sessions, subjects consumed one of three different test meals on two separate occasions. The test meals were: a standard meal plus 5 g PGX; a standard meal plus 4.5 g of PGX as softgels; and a standard meal plus 5 g of WD. Subjects recorded fullness using a labelled magnitude scale at 0, 15, 30, 45, 60, 90, and 120 min and the total area under the curve (AUC), mean fullness vs. time was calculated. The meals with PGX (in granular and softgel form) gave higher satiety (AUC) (477 ± 121 and 454 ± 242 cm·min), than the meal with WD (215 ± 261 cm·min) (p < 0.001). Subjects had blood glucose levels measured after the meals with PGX (granules) and WD. Glucose response (AUC) was significantly lower (p < 0.001) after the PGX meal than for the WD meal.  The high viscosity reported for PGX is a likely mechanism behind the significant satiety and blood glucose modulating effects observed in this study. PMID:27164135

  10. A simple immune complex dissociation ELISA for leishmaniasis: standardization of the assay in experimental models and preliminary results in canine and human samples.

    PubMed

    de Carvalho, Camila Aparecida; Partata, Anette Kelsei; Hiramoto, Roberto Mitsuyoshi; Borborema, Samanta Etel Treiger; Meireles, Luciana Regina; Nascimento, Nanci do; de Andrade, Heitor Franco

    2013-02-01

    Visceral leishmaniasis, caused by Leishmania (Leishmania) chagasi, is a chronic parasitic disease of humans and dogs. Confirmation of the protozoal agent in bone marrow, lymph node or spleen aspirate is diagnostic, while specific-IgG serology is used mainly for epidemiology despite the general presence of high levels of serum immunoglobulin. Anecdotal reports of false-negative serology in active disease cases are known and are ascribed to the formation of immune complexes. Because dissociation of immune complexes can be accomplished by acid treatment, we devised a simple, routine enzyme immunoassay (ELISA) for the dissociation of immune complexes in serum samples using acid treatment in wells adsorbed with Leishmania antigen (dELISA). Confirmatory acid dot-blot was also developed for antigen detection by anti-Leishmania rabbit antiserum. In experimental L. chagasi hamster models, immune complexes interfered with ELISA mostly in the 30 and 60 days postinfection, according to both dELISA and antigen dot-blot results. In larger samples from endemic areas, dELISA was positive in 10% of seronegative dog samples (7/70) and 3.5% in negative human samples (3/88), showing that dELISA could be used in the serodiagnosis of visceral leishmaniasis. Moreover, dELISA could be used as an alternative approach to screening asymptomatic visceral leishmaniasis patients, instead of invasive confirmatory testing. PMID:23123344

  11. Standards in Mathematics Teaching.

    ERIC Educational Resources Information Center

    Brookes, Bill

    1978-01-01

    This article is based on a lecture given at the 1978 Easter Course at Padgate College of Higher Education. The lecture is an analysis of the complexity of mathematics teaching and the setting of teaching standards. (MN)

  12. [{sup 18}F]FDG-PET Standard Uptake Value as a Metabolic Predictor of Bone Marrow Response to Radiation: Impact on Acute and Late Hematological Toxicity in Cervical Cancer Patients Treated With Chemoradiation Therapy

    SciTech Connect

    Elicin, Olgun; Callaway, Sharon; Prior, John O.; Bourhis, Jean; Ozsahin, Mahmut; Herrera, Fernanda G.

    2014-12-01

    Purpose: To quantify the relationship between bone marrow (BM) response to radiation and radiation dose by using {sup 18}F-labeled fluorodeoxyglucose positron emission tomography [{sup 18}F]FDG-PET standard uptake values (SUV) and to correlate these findings with hematological toxicity (HT) in cervical cancer (CC) patients treated with chemoradiation therapy (CRT). Methods and Materials: Seventeen women with a diagnosis of CC were treated with standard doses of CRT. All patients underwent pre- and post-therapy [{sup 18}F]FDG-PET/computed tomography (CT). Hemograms were obtained before and during treatment and 3 months after treatment and at last follow-up. Pelvic bone was autosegmented as total bone marrow (BM{sub TOT}). Active bone marrow (BM{sub ACT}) was contoured based on SUV greater than the mean SUV of BM{sub TOT}. The volumes (V) of each region receiving 10, 20, 30, and 40 Gy (V{sub 10}, V{sub 20}, V{sub 30}, and V{sub 40}, respectively) were calculated. Metabolic volume histograms and voxel SUV map response graphs were created. Relative changes in SUV before and after therapy were calculated by separating SUV voxels into radiation therapy dose ranges of 5 Gy. The relationships among SUV decrease, radiation dose, and HT were investigated using multiple regression models. Results: Mean relative pre-post-therapy SUV reductions in BM{sub TOT} and BM{sub ACT} were 27% and 38%, respectively. BM{sub ACT} volume was significantly reduced after treatment (from 651.5 to 231.6 cm{sup 3}, respectively; P<.0001). BM{sub ACT} V{sub 30} was significantly correlated with a reduction in BM{sub ACT} SUV (R{sup 2}, 0.14; P<.001). The reduction in BM{sub ACT} SUV significantly correlated with reduction in white blood cells (WBCs) at 3 months post-treatment (R{sup 2}, 0.27; P=.04) and at last follow-up (R{sup 2}, 0.25; P=.04). Different dosimetric parameters of BM{sub TOT} and BM{sub ACT} correlated with long-term hematological outcome. Conclusions: The volumes of BM

  13. Precise measurement of the lattice spacing of LaB6 standard powder by the x-ray extended range technique using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Chantler, C. T.; Tran, C. Q.; Cookson, D. J.

    2004-04-01

    We used the basis of the x-ray extended range technique to measure the lattice spacing of LaB6 standard powder samples relative to silicon 640b standard powder samples with an accuracy of 5× 10-5 Å . Measurements were not constrained to one energy but were carried out over a 5 keV 20 keV energy range. These measurements used powder diffraction to determine the synchrotron beam energy, to diagnose discrepancies in the nominal calibrated beam energies, and to determine beam energy bandwidths as a function of energy. More specifically, this technique is able to yield a result independent of certain energy-dependent systematics and to yield the most accurate determination of the lattice spacing of NIST SRM 660 LaB6 standard powder so far undertaken. This has direct application to beam line energy calibration, structural evaluation, edge energy calibration, and lattice spacing determinations.

  14. Complexation of Optoelectronic Systems

    NASA Astrophysics Data System (ADS)

    Boreisho, A. S.; Il‧in, M. Yu.; Konyaev, M. A.; Mikhailenko, A. S.; Morozov, A. V.; Strakhov, S. Yu.

    2016-06-01

    Problems of increasing the efficiency and the functionality of complex optoelectronic systems for monitoring real atmospheric conditions and of their use are discussed. It is shown by the example of a meteorological complex comprising an infrared wind-sensing lidar and an X-range Doppler radar that the complexation of probing systems working in different electromagnetic-radiation ranges opens up new opportunities for determining the meteorological parameters of a turbulent atmosphere and investigating the interaction of radiation with it.

  15. Topical Hyaluronic acid vs. Standard of Care for the Prevention of Radiation Dermatitis after Adjuvant Radiotherapy for Breast Cancer: Single-Blind Randomized Phase III Clinical Trial

    PubMed Central

    Pinnix, Chelsea; Perkins, George H.; Strom, Eric A.; Tereffe, Welela; Woodward, Wendy; Oh, Julia L.; Arriaga, Lisa; Munsell, Mark F.; Kelly, Patrick; Hoffman, Karen E.; Smith, Benjamin D.; Buchholz, Thomas A.; Yu, T. Kuan

    2014-01-01

    Purpose To determine the efficacy of an emulsion containing hyaluronic acid to reduce the development of ≥ grade 2 radiation dermatitis after adjuvant breast radiation (RT) compared with best supportive care. Materials and Methods Women with breast cancer who had undergone lumpectomy and were to receive whole-breast RT to 50 Gy with a 10- to 16-Gy surgical bed boost were enrolled in a prospective randomized trial to compare the effectiveness of a hyaluronic acid-based gel (RadiaPlex) and a petrolatum-based gel (Aquaphor) for preventing the development of dermatitis. Each patient was randomly assigned to use hyaluronic acid gel, on the medial half or the lateral half of the irradiated breast, and the control gel to the other half. Dermatitis was graded weekly according to the Common Terminology Criteria v3.0 by the treating physician, who was blinded as to which gel was used on which area of the breast. The primary endpoint was development of ≥grade 2 dermatitis. Results The study closed early based on a recommendation from the Data and Safety Monitoring Board after 74 of the planned 92 patients were enrolled. Breast skin treated with the hyaluronic acid gel developed significantly higher rate of ≥grade 2 dermatitis than did skin treated with petrolatum gel (61.5% [40/65] vs. 47.7% [31/65], P = 0.027). Only one patient developed grade 3 dermatitis using either gel. A higher proportion of patients had worse dermatitis in the breast segment treated with hyaluronic acid gel than petrolatum gel at the end of RT (42% vs. 14%, P = 0.003). Conclusion We found no benefit from use of a topical hyaluronic acid-based gel for reducing the development of grade ≥2 dermatitis after adjuvant RT for breast cancer. Additional studies are needed to determine the efficacy of hyaluronic acid-based gel in controlling radiation dermatitis symptoms after they develop. PMID:22172912

  16. Phase II Study of the Addition of Bevacizumab to Standard Chemoradiation for Loco-regionally Advanced Nasopharyngeal Carcinoma: Radiation Therapy Oncology Group (RTOG) Trial 0615

    PubMed Central

    Lee, Nancy Y.; Zhang, Ed; Pfister, David. G.; Kim, John; Garden, Adam. S.; Mechalakos, James; Hu, Kenneth; Le, Quynh T.; Colevas, A. Dimitrios; Glisson, Bonnie S.; Chan, Anthony T.C.; Ang, K. Kian

    2016-01-01

    Purpose We sought to improve the outcomes for loco-regionally advanced nasopharyngeal carcinoma (NPC) by testing the feasibility/safety of adding bevacizumab to chemoradiation. Patients/Methods Eligible patients with ≥T2b and/or positive node(s) were prescribed 3 cycles of bevacizumab (15 mg/kg) and cisplatin (100 mg/m2) both given on days 1, 22, and 43 of radiation (70 Gy) using IMRT delivered over 33 days on a daily basis, Monday through Friday. This is followed by 3 cycles of bevacizumab (15 mg/kg), cisplatin (80 mg/m2) both were given on days 64, 85, and 106 and fluorouracil (1000 mg/m2/d) on days 64–67, 85–88, 106–109 after radiation. The primary endpoint was to evaluate the safety of the addition of bevacizumab to chemoradiation, specifically looking at treatment-related Grade 4 hemorrhage and/or any Grade 5 adverse event in the first year. Toxicity during and after treatment were collected along with tumor control endpoints. The analysis was done per protocol. This protocol has completed its target accrual. Results There were a total of 46 patients enrolled in this study of whom 44 patients were eligible for analysis. No grade 3–4 hemorrhage or grade 5 adverse events were observed; 9 patients (20.5%) experienced grade 1–2 hemorrhage. Grade 4 adverse events were experienced by the following numbers of patients: leukopenia NOS – 6; lymphopenia – 5; neutrophil count – 5; pharyngolaryngeal pain – 2; hemoglobin – 1; infection with grade 3–4 neutrophils (blood) – 1; infection with grade 3–4 neutrophils [skin (cellulitis)] – 1; tinnitus – 1; thrombosis – 1; radiation mucositis – 1. The most common grade 3 adverse events were radiation mucositis – 33; dysphagia – 25; and mucositis/stomatitis (clinical exam) (pharynx) – 15. Two patients experienced late grade 3 xerostomia. Other late grade 3 adverse events were: dysphagia – 5; hearing impaired – 3; neuralgia NOS – 2; constitutional symptoms (other) – 1; dehydration

  17. MR Evaluation of Radiation Synovectomy of the Knee by Means of Intra-articular Injection of Holmium-166-Chitosan Complex in Patients with Rheumatoid Arthritis: Results at 4-month Follow-up

    PubMed Central

    Lee, Sang Hoon; Kim, Ho Seok; Lee, Jong Doo; Song, Jungsik; Lee, Soo Kon

    2003-01-01

    Objective To determine whether MRI is able to demonstrate the effect of radiation synovectomy after the intra-articular injection of holmium-166-chitosan complex for the treatment of rheumatoid arthritis of the knee. Materials and Methods Fourteen patients aged 36-59 years were treated with 10-20 mCi of holmium-166-chitosan complex. A criterion for inclusion in this study was the absence of observable improvement after 3- or more months of treatment of the knee with disease-modifying anti-rheumatic drugs. MR images were acquired both prior to and 4-months after treatment. Clinical evaluation included the use of visual analog scales to assess pain, and the circumference of the knee and its range of motion were also determined. MR evaluation included measurement of the volume of synovial enhancement and wall thickness, the amount of joint effusion, and quantifiable scoring of bone erosion, bone edema and lymph nodes. Results Visual analog scale readings decreased significantly after radiation synovectomy (p < 0.05). MRI showed that joint effusion decreased significantly (p < 0.05), and that the volume of synovial enhancement tended to decrease, but to an insignificant extent (p = 0.107). Conclusion The decreased joint effusion noted at 4-month follow-up resulted from radiation synovectomy of the rheumatoid knee by means of intra-articular injection of holmium-166-chitosan complex. PMID:14530646

  18. Topical Hyaluronic Acid vs. Standard of Care for the Prevention of Radiation Dermatitis After Adjuvant Radiotherapy for Breast Cancer: Single-Blind Randomized Phase III Clinical Trial

    SciTech Connect

    Pinnix, Chelsea; Perkins, George H.; Strom, Eric A.; Tereffe, Welela; Woodward, Wendy; Oh, Julia L.; Arriaga, Lisa; Munsell, Mark F.; Kelly, Patrick; Hoffman, Karen E.; Smith, Benjamin D.; Buchholz, Thomas A.; Yu, T. Kuan

    2012-07-15

    Purpose: To determine the efficacy of an emulsion containing hyaluronic acid to reduce the development of {>=}Grade 2 radiation dermatitis after adjuvant breast radiation compared with best supportive care. Methods and Materials: Women with breast cancer who had undergone lumpectomy and were to receive whole-breast radiotherapy to 50 Gy with a 10- to 16-Gy surgical bed boost were enrolled in a prospective randomized trial to compare the effectiveness of a hyaluronic acid-based gel (RadiaPlex) and a petrolatum-based gel (Aquaphor) for preventing the development of dermatitis. Each patient was randomly assigned to use hyaluronic acid gel on the medial half or the lateral half of the irradiated breast and to use the control gel on the other half. Dermatitis was graded weekly according to the Common Terminology Criteria v3.0 by the treating physician, who was blinded as to which gel was used on which area of the breast. The primary endpoint was development of {>=}Grade 2 dermatitis. Results: The study closed early on the basis of a recommendation from the Data and Safety Monitoring Board after 74 of the planned 92 patients were enrolled. Breast skin treated with the hyaluronic acid gel developed a significantly higher rate of {>=}Grade 2 dermatitis than did skin treated with petrolatum gel: 61.5% (40/65) vs. 47.7% (31/65) (p = 0.027). Only 1ne patient developed Grade 3 dermatitis using either gel. A higher proportion of patients had worse dermatitis in the breast segment treated with hyaluronic acid gel than in that treated with petrolatum gel at the end of radiotherapy (42% vs. 14%, p = 0.003). Conclusion: We found no benefit from the use of a topical hyaluronic acid-based gel for reducing the development of {>=}Grade 2 dermatitis after adjuvant radiotherapy for breast cancer. Additional studies are needed to determine the efficacy of hyaluronic acid-based gel in controlling radiation dermatitis symptoms after they develop.

  19. Phase function, backscatter, extinction, and absorption for standard radiation atmosphere and El Chichon aerosol models at visible and near-infrared wavelengths

    NASA Technical Reports Server (NTRS)

    Whitlock, C. H.; Suttles, J. T.; Lecroy, S. R.

    1985-01-01

    Tabular values of phase function, Legendre polynominal coefficients, 180 deg backscatter, and extinction cross section are given for eight wavelengths in the atmospheric windows between 0.4 and 2.2 microns. Also included are single scattering albedo, asymmetry factor, and refractive indices. These values are based on Mie theory calculations for the standard rediation atmospheres (continental, maritime, urban, unperturbed stratospheric, volcanic, upper atmospheric, soot, oceanic, dust, and water-soluble) assest measured volcanic aerosols at several time intervals following the El Chichon eruption. Comparisons of extinction to 180 deg backscatter for different aerosol models are presented and related to lidar data.

  20. Transfer standard for beta decay radionuclides in radiotherapy.

    PubMed

    Thieme, Klaus; Beinlich, Uwe; Fritz, Eberhard

    2004-01-01

    The measurement of the activity of therapeutic radiopharmaceuticals prior to the administration to patients is normally achieved via the use of radionuclide calibrators. An accurate measurement of the activity of pure beta-emitters is complex. Calibration problems can be solved by combining a primary calibration with a 90Y reference solution and a 90Sr/90Y transfer standard with a solid source, simulating geometric effects caused by high energetic beta radiation. The recent development of a 90Sr/90Y transfer standard for this purpose is reported. PMID:14987695

  1. Cadmium(II), nickel(II), and zinc(II) complexes of vacataporphyrin: a variable annulene conformation inside a standard porphyrin frame.

    PubMed

    Pacholska-Dudziak, Ewa; Skonieczny, Janusz; Pawlicki, Miłosz; Szterenberg, Ludmiła; Latos-Grazyński, Lechosław

    2005-11-28

    5,10,15,20-Tetraaryl-21-vacataporphyrin, 1 (butadieneporphyrin, annulene-porphyrin hybrid), which contains a vacant space instead of heteroatomic bridge, gives diamagnetic zinc(II) 1-ZnCl and cadmium(II) 1-CdCl and paramagnetic nickel(II) 1-NiCl complexes. A metal ion is bound in the macrocyclic cavity by three pyrrolic nitrogens. Coordination imposes a steric constraint on the geometry of the ligand and leads to two stereoisomers with a butadiene fragment oriented toward 1-MCl-i or outward 1-MCl-o of the macrocyclic center. 1-CdCl-o, 1-ZnCl-o, and the free base share a common 1H NMR spectral pattern as the basic structural features of 1 are preserved after metal ion insertion. The 1H NMR spectra of 1-CdCl-i and 1-ZnCl-i reflect a decrease of aromaticity accounted for by the inverted butadiene geometry. The proximity of the butadiene fragment to the metal ion induces direct couplings between the spin-active nucleus of the metal ((111/113)Cd) and the adjacent 1H nuclei of butadiene. The pattern of chemical shifts detected for isomeric 1-NiCl-i and 1-NiCl-o is typical for high-spin nickel(II) complexes of porphyrin analogues. Resonances 2,3-H of 1-NiCl-o or 1-NiCl-i present the chemical shift typical for the beta-H pyrrolic position despite the vacancy in the location of nitrogen-21. Coordination of imidazole, methanol-d4, acetonitrile-d3, or chloride converts 1-NiCl-i and 1-NiCl-o into distinct species which contain two axial ligands: 1-Ni(Im)2+; 1-Ni(CD3OD)2+; 1-Ni(CD3CN)2+; 1-Ni(Cl)2-. The density functional theory (DFT) has been applied to model the molecular and electronic structure of feasible 1-CdCl stereoisomers. The total energies calculated using the B3LYP/LANL2DZ approach demonstrate a very small energy difference (2.3 kcal/mol) between 1-CdCl-o and 1-CdCl-i stereoisomers consistent with their concurrent formation. PMID:16296834

  2. ULTRA SECURE HIGH RELIABILITY WIRELESS RADIATION MONITOR

    SciTech Connect

    Cordaro, J.; Shull, D.; Farrar, M.; Reeves, G.

    2011-08-03

    Radiation monitoring in nuclear facilities is essential to safe operation of the equipment as well as protecting personnel. In specific, typical air monitoring of radioactive gases or particulate involves complex systems of valves, pumps, piping and electronics. The challenge is to measure a representative sample in areas that are radioactively contaminated. Running cables and piping to these locations is very expensive due to the containment requirements. Penetration into and out of an airborne or containment area is complex and costly. The process rooms are built with thick rebar-enforced concrete walls with glove box containment chambers inside. Figure 1 shows high temperature radiation resistance cabling entering the top of a typical glove box. In some case, the entire processing area must be contained in a 'hot cell' where the only access into the chamber is via manipulators. An example is shown in Figure 2. A short range wireless network provides an ideal communication link for transmitting the data from the radiation sensor to a 'clean area', or area absent of any radiation fields or radioactive contamination. Radiation monitoring systems that protect personnel and equipment must meet stringent codes and standards due to the consequences of failure. At first glance a wired system would seem more desirable. Concerns with wireless communication include latency, jamming, spoofing, man in the middle attacks, and hacking. The Department of Energy's Savannah River National Laboratory (SRNL) has developed a prototype wireless radiation air monitoring system that address many of the concerns with wireless and allows quick deployment in radiation and contamination areas. It is stand alone and only requires a standard 120 VAC, 60 Hz power source. It is designed to be mounted or portable. The wireless link uses a National Security Agency (NSA) Suite B compliant wireless network from Fortress Technologies that is considered robust enough to be used for classified data

  3. Training course for radiation safety technicians

    NASA Technical Reports Server (NTRS)

    Lasuk, S. R.; Moe, H. J.

    1967-01-01

    Course of instruction includes sections on basic information, natural radioactivity, properties of alpha, beta, gamma, X rays, and neutrons, concepts of radiation units and dose determinations, shielding, biological effects, background radiation, radiation protection standards, and internal dose calculation.

  4. Toward Reliable Industrial Radiation Thermometry

    NASA Astrophysics Data System (ADS)

    Yamada, Y.; Ishii, J.

    2015-08-01

    Application of radiation thermometry in industrial scenes is rapidly increasing with the widespread use of low-cost infrared thermometers and thermal imagers. However, their performances are not always up to the users' expectations. This is often due to lack of appropriate information on the limitations of the instrument performance and of radiation thermometry itself. In this article, these limitations are disclosed, namely the targeting capabilities of the thermometers including the size-of-source effect of thermal imagers, reflection errors, and unknown emissivity of the measurement object. Attempts made at the NMIJ are introduced, which aim at alleviating the effect of these difficulties. Two-color radiation thermometers have been neglected from the traceability chain and from standardization efforts due to their technical complexity. Recent activities to incorporate them effectively in the calibration chain and to establish international standards are presented. Calibration of low-cost thermometers with a fixed instrumental emissivity setting has been an issue for calibration laboratories. Simple apparatus that enables calibration of such instruments is described. Methods to compensate for unknown emissivities are presented utilizing auxiliary sources to realize a blackbody condition, which is applied to thermal imagers to overcome the problem of the size-of-source effect and reflection error at the same time. Extensions of the technique to objects with specular and scattering surfaces are described. Such efforts are encouraged in the thermometry community since they are essential in establishing an unbroken chain of traceability to the industrial front.

  5. Effects of Complex Interplanetary Structures on the Dynamics of the Earth's Outer Radiation Belt During the 16-30 September 2014 Period: II) Corotating Solar Wind Stream

    NASA Astrophysics Data System (ADS)

    Souza, V. M. C. E. S.; Da Silva, L. A.; Sibeck, D. G.; Alves, L. R.; Jauer, P. R.; Dias Silveira, M. V.; Medeiros, C.; Marchezi, J.; Rockenbach, M.; Baker, D. N.; Kletzing, C.; Kanekal, S. G.; Georgiou, M.; Mendes, O., Jr.; Dal Lago, A.; Vieira, L. E. A.

    2015-12-01

    We present a case study describing the dynamics of the outer radiation belt for two different solar wind conditions. First, we discuss a dropout of outer belt energetic electron fluxes corresponding to the arrival of an interplanetary coronal mass ejection (ICME) followed by a corotating stream in September 2014. Second, we discuss the reformation of the outer radiation belt that began on September 22nd. We find that the arrival of the ICME and the corotating interaction region that preceded the stream cause a long-duration (many day) dropout of high-energy electrons. The recovery in radiation belt fluxes only begins when the high-speed stream begins to develop IMF Bz fluctuations and auroral activity resumes. Furthermore, during periods in which several consecutive solar wind structures appear, the first structure primes the outer radiation belt prior to the interaction of the subsequent solar wind structures with the magnetosphere. Consequently, the evolution of the outer radiation belt through the solar cycle is significantly affected by the dominant structure of each phase of the cycle. We use energetic electron and magnetic field observations provided by the Van Allen Probes, THEMIS, and GOES missions.

  6. Intensity-Modulated Radiotherapy Reduces Radiation-Induced Morbidity and Improves Health-Related Quality of Life: Results of a Nonrandomized Prospective Study Using a Standardized Follow-Up Program

    SciTech Connect

    Vergeer, Marije R. Doornaert, Patricia A.H.; Rietveld, Derek H.F.; Leemans, C. Rene; Langendijk, Johannes A.

    2009-05-01

    Purpose: The purpose of this study was to compare intensity-modulated radiation therapy (IMRT) and three-dimensional conventional radiotherapy (3D-CRT) with regard to patient-rated xerostomia, Radiation Therapy Oncology Group (RTOG) acute and late xerostomia and health-related quality of life (HRQoL) among patients with head and neck squamous cell carcinoma (HNSCC). Methods and Materials: Included were 241 patients with HNSCC treated with bilateral irradiation {+-} chemotherapy. Since 2000, all patients treated with HNSCC were included in a program, which prospectively assessed acute and late morbidity according to the RTOG and HRQoL on a routine basis at regular intervals. Before October 2004, all patients were treated with 3D-CRT (N = 150). After clinical implementation in October 2004, 91 patients received IMRT. In this study, the differences regarding RTOG toxicity, xerostomia, and other items of HRQoL were analyzed. Results: The use of IMRT resulted in a significant reduction of the mean dose of the parotid glands (27 Gy vs. 43 Gy (p < 0.001). During radiation, Grade 2 RTOG xerostomia was significantly less with IMRT than with 3D-CRT. At 6 months, the prevalence of patient-rated moderate to severe xerostomia and Grade 2 or higher RTOG xerostomia was significantly lower after IMRT versus 3D-CRT. Treatment with IMRT also had a positive effect on several general and head and neck cancer-specific HRQoL dimensions. Conclusions: IMRT results in a significant reduction of patient- and observer-rated xerostomia, as well as other head and neck symptoms, compared with standard 3D-CRT. These differences translate into a significant improvement of the more general dimensions of HRQoL.

  7. 40 CFR 190.10 - Standards for normal operations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....10 Section 190.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR NUCLEAR POWER OPERATIONS Environmental... operations and to radiation from these operations. (b) The total quantity of radioactive materials...

  8. Comparison of organ-specific-radiation dose levels between 70 kVp perfusion CT and standard tri-phasic liver CT in patients with hepatocellular carcinoma using a Monte-Carlo-Simulation-based analysis platform

    PubMed Central

    Gawlitza, J.; Haubenreisser, H.; Meyer, M.; Hagelstein, C.; Sudarski, S.; Schoenberg, S.O.; Henzler, T.

    2016-01-01

    Purpose The aim of this study was to systematically compare organ-specific-radiation dose levels between a radiation dose optimized perfusion CT (dVPCT) protocol of the liver and a tri-phasic standard CT protocol of the liver using a Monte-Carlo-Simulation-based analysis platform. Methods and materials The complete CT data of 52 patients (41 males; mean age 65 ± 12) with suspected HCC that underwent dVPCT examinations on a 3rd generation dual-source CT (Somatom Force, Siemens) with a dose optimized tube voltage of 70 kVp or 80 kVp were exported to an analysis platform (Radimetrics, Bayer). The dVPCT studies were matched with a reference group of 50 patients (35 males; mean age 65 ± 14) that underwent standard tri-phasic CT (sCT) examinations of the liver with 130 kVp using the calculated water-equivalent-diameter of the patients. The analysis platform was used for the calculation of the organ-specific effective dose (ED) as well as global radiation-dose parameters (ICRP103). Results The organ-specific ED of the dVPCT protocol was statistically significantly lower when compared to the sCT in 14 of 21, and noninferior in a total of 18 of 21 examined items (all p < 0.05). The EDs of the dVPCT examinations were especially in the dose sensitive organs such as the red marrow (17.3 mSv vs 24.6 mSv, p = < 0.0001) and the liver (33.3 mSv vs 46.9 mSv, p = 0.0003) lower when compared to the sCT. Conclusion Our results suggest that dVPCT performed at 70 or 80 kVp compares favorably to sCT performed with 130 kVp with regard to effective organ dose levels, especially in dose sensitive organs, while providing additional functional information which is of paramount importance in patients undergoing novel targeted therapies. PMID:27200404

  9. Establishment of 6- to 7-MeV high-energy gamma-ray calibration fields produced using the 4-MV Van de Graaff accelerator at the Facility of Radiation Standards, Japan Atomic Energy Agency.

    PubMed

    Kowatari, Munehiko; Tanimura, Yoshihiko

    2016-03-01

    A 6- to 7-MeV high-energy gamma-ray field, produced by the nuclear reaction of (19)F(p, αγ)(16)O, has been established at the Facility of Radiation Standards (FRS) in Japan Atomic Energy Agency for calibration purposes. Basic dosimetric quantities (i.e. averaged gamma-ray energy, air-kerma-to-dose equivalent conversion coefficients and air kerma rates at the point of test) have been precisely determined through a series of measurements using the NaI(Tl) spectrometer and an ionisation chamber coupled with an appropriate build-up material. The measurements obtained comply with values recommended by the International Organization for Standardization for an 'R-F field'. The neutron contamination component for the field has also been measured by means of a conventional neutron dose equivalent meter (the so-called neutron rem-counter) and determined to be ∼ 0.5 % of the total dose equivalent. PMID:26012483

  10. Determination of complex permittivity from propagation constant measurement with planar transmission lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new two-standard calibration procedure is outlined for determining the complex permittivity of materials from the propagation constant measured with planar transmission lines. Once calibrated, a closed-form expression for the material permittivity is obtained. The effects of radiation and conducto...

  11. Microwave Radiation Detector

    NASA Technical Reports Server (NTRS)

    Lesh, J. R.

    1984-01-01

    Direct photon detector responds to microwave frequencies. Method based on trapped-ion frequency-generation standards proposed to detect radio-frequency (RF) radiation at 40.5 GHz. Technique used for directdetection (RF) communication, radar, and radio astronomy.

  12. International Standards.

    ERIC Educational Resources Information Center

    Havard-Williams, Peter

    1982-01-01

    Discussion of standardization on an international scale for resource sharing--cooperation, coordination, interlibrary loans, cooperative acquisition and cataloging--focuses on a definition of standards; the development of standards for cataloging; public, school, and university libraries; and library education. A 60-item bibliography is included.…

  13. Mitotic regulator Nlp interacts with XPA/ERCC1 complexes and regulates nucleotide excision repair (NER) in response to UV radiation.

    PubMed

    Ma, Xiao-Juan; Shang, Li; Zhang, Wei-Min; Wang, Ming-Rong; Zhan, Qi-Min

    2016-04-10

    Cellular response to DNA damage, including ionizing radiation (IR) and UV radiation, is critical for the maintenance of genomic fidelity. Defects of DNA repair often result in genomic instability and malignant cell transformation. Centrosomal protein Nlp (ninein-like protein) has been characterized as an important cell cycle regulator that is required for proper mitotic progression. In this study, we demonstrate that Nlp is able to improve nucleotide excision repair (NER) activity and protects cells against UV radiation. Upon exposure of cells to UVC, Nlp is translocated into the nucleus. The C-terminus (1030-1382) of Nlp is necessary and sufficient for its nuclear import. Upon UVC radiation, Nlp interacts with XPA and ERCC1, and enhances their association. Interestingly, down-regulated expression of Nlp is found to be associated with human skin cancers, indicating that dysregulated Nlp might be related to the development of human skin cancers. Taken together, this study identifies mitotic protein Nlp as a new and important member of NER pathway and thus provides novel insights into understanding of regulatory machinery involved in NER. PMID:26805762

  14. Effect of the vibrational excitation on the non-radiative deactivation rate of the S 1 state of p-cresol(NH 3) complex

    NASA Astrophysics Data System (ADS)

    Oldani, A. N.; Mobbili, M.; Marceca, E.; Ferrero, J. C.; Pino, G. A.

    2009-03-01

    The effect of the CH 3 group on the lifetime of the S 1 state of the p-cresol(NH 3) complex was investigated by means of REMPI, LIF, DF spectroscopy and abinitio calculations. At variance with PhOH(NH 3) for which vibrational-mode specificity was reported, the lifetime of the S 1 state of the p-cresol(NH 3) complex decreases monotonically upon vibrational excitation indicating that randomization of energy takes place at low excitation energy. This result is analyzed as the consequence of a stronger coupling of the complex intermolecular modes with those of the CH 3 group.

  15. Comparison of Standard and Quadruple-Phase Contrast Material Injection for Artifacts, Image Quality, and Radiation Dose in the Evaluation of Head and Neck Cancer Metastases.

    PubMed

    Saade, Charbel; El-Merhi, Fadi; Mayat, Ahmad; Brennan, Patrick C; Yousem, David

    2016-05-01

    Purpose To investigate opacification of head and neck vasculature during computed tomography (CT) of supraclavicular lymph nodes with a quadruple-phase contrast media and saline dual-injection protocol. Materials and Methods This retrospective study was institutional review board approved. In 180 consecutive patients, routine head and neck CT was performed with one of two protocols: protocol A, craniocaudal scan direction with 100 mL of contrast material injected intravenously as a single bolus; or protocol B, 100 mL of contrast material injected in four phases (phases 1-2, 60 mL of contrast material and saline injected at 2.5 mL/sec; phases 3-4, 40 mL of contrast material and saline injected at 2.5 mL/sec); both protocols had a fixed scan delay of 70 seconds. Attenuation of supraclavicular arteries and veins was measured with arteriovenous contrast ratio (AVCR) and contrast-to-noise ratio (CNR). Effective dose was calculated. Data were compared with the two-sample t test. Receiver operating characteristic (ROC) and visual grading characteristic analyses were performed. Results Arterial attenuation was up to 20% higher (P < .05) after protocol B (mean ± standard deviation, 234.5 HU ± 33.2) than protocol A (160.0 HU ± 29.5). Venous system attenuation was significantly lower in protocol B (164.0 HU ± 17.0) than in protocol A (664.0 HU ± 12.0), with up to a 75% reduction (P < .0001). Protocol B generated significant (P < .0001) improvements in AVCR at multiple anatomic sites. At all anatomic levels, mean CNR with protocol B (34.4 HU ± 9.0) was significantly higher than that with protocol A (14.5 HU ± 14.0) (P < .0313). Effective dose was significantly reduced with protocol B (2.6 mSv ± 0.4 vs 3.2 mSv ± 0.8 with protocol A; P < .0041). ROC analysis demonstrated significantly higher area under the ROC curve for protocol B (P < .0022), with interreader agreement increasing from poor to excellent in lymph node visualization. Conclusion Significant improvement in

  16. Radiation treatment of pharmaceuticals

    NASA Astrophysics Data System (ADS)

    Dám, A. M.; Gazsó, L. G.; Kaewpila, S.; Maschek, I.

    1996-03-01

    Product specific doses were calculated for pharmaceuticals to be radiation treated. Radio-pasteurization dose were determined for some heat sensitive pharmaceutical basic materials (pancreaton, neopancreatin, neopancreatin USP, duodenum extract). Using the new recommendation (ISO standards, Method 1) dose calculations were performed and radiation sterilization doses were determined for aprotinine and heparine Na.

  17. 40 CFR 191.03 - Standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Standards. 191.03 Section 191.03... ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR MANAGEMENT AND DISPOSAL OF SPENT NUCLEAR FUEL, HIGH-LEVEL AND TRANSURANIC RADIOACTIVE WASTES Environmental Standards for Management and Storage § 191.03 Standards....

  18. 40 CFR 191.03 - Standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Standards. 191.03 Section 191.03... ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR MANAGEMENT AND DISPOSAL OF SPENT NUCLEAR FUEL, HIGH-LEVEL AND TRANSURANIC RADIOACTIVE WASTES Environmental Standards for Management and Storage § 191.03 Standards....

  19. 40 CFR 191.03 - Standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Standards. 191.03 Section 191.03... ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR MANAGEMENT AND DISPOSAL OF SPENT NUCLEAR FUEL, HIGH-LEVEL AND TRANSURANIC RADIOACTIVE WASTES Environmental Standards for Management and Storage § 191.03 Standards....

  20. 40 CFR 191.04 - Alternative standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Alternative standards. 191.04 Section... PROGRAMS ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR MANAGEMENT AND DISPOSAL OF SPENT NUCLEAR FUEL....04 Alternative standards. (a) The Administrator may issue alternative standards from those...

  1. 40 CFR 191.03 - Standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Standards. 191.03 Section 191.03... ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR MANAGEMENT AND DISPOSAL OF SPENT NUCLEAR FUEL, HIGH-LEVEL AND TRANSURANIC RADIOACTIVE WASTES Environmental Standards for Management and Storage § 191.03 Standards....

  2. Energetic neutron and gamma-ray spectra under the earth radiation belts according to "SALYUT-7" [correction of "SALUTE-7"]-"KOSMOS-1686" orbital complex and "CORONAS-I" satellite data.

    PubMed

    Bogomolov, A V; Dmitriev, A V; Myagkova, I N; Ryumin, S P; Smirnova, O N; Sobolevsky, I M

    1998-01-01

    The spectra of neutrons >10 MeV and gamma-rays 1.5-100 MeV under the Earth Radiation Belts, restored from the data, obtained onboard orbital complex "SALYUT-7" [correction of "SALUTE-7"]-"KOSMOS-1686", are presented. The spectra shapes are similar to those for albedo neutrons and gamma-rays, but absolute values of their fluxes (0.2 cm-2 s-1 for neutrons, 0.8 cm-2 s-1 for gamma-rays at the equator and 1.2 cm-2 s-1, 1.9 cm-2 s-1, accordingly, at L=1.9) are several times as large. It is possibly explained by the fact that most of the detected particles were produced by the cosmic ray interactions with the orbital complex matter. Neutron and gamma-ray fluxes obtained from "CORONAS-1" data are near those for albedo particles. PMID:11542904

  3. Syntactic Complexity as an Aspect of Text Complexity

    ERIC Educational Resources Information Center

    Frantz, Roger S.; Starr, Laura E.; Bailey, Alison L.

    2015-01-01

    Students' ability to read complex texts is emphasized in the Common Core State Standards (CCSS) for English Language Arts and Literacy. The standards propose a three-part model for measuring text complexity. Although the model presents a robust means for determining text complexity based on a variety of features inherent to a text as well as…

  4. Shortwave Radiation

    NASA Technical Reports Server (NTRS)

    Klassen, Steve; Bugbee, Bruce

    2005-01-01

    Accurate shortwave radiation data is critical to evapotranspiration (ET) models used for developing irrigation schedules to optimize crop production while saving water, minimizing fertilizer, herbicide, and pesticide applications, reducing soil erosion, and protecting surface and ground water quality. Low cost silicon cell pyranometers have proven to be sufficiently accurate and robust for widespread use in agricultural applications under unobstructed daylight conditions. More expensive thermopile pyranometers are required for use as calibration standards and measurements under light with unique spectral properties (electric lights, under vegetation, in greenhouses and growth chambers). Routine cleaning, leveling, and annual calibration checks will help to ensure the integrity of long-term data.

  5. Radiation health research, 1986 - 1990

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A collection of 225 abstracts of radiation research sponsored by NASA during the period 1986 through 1990 is reported. Each abstract was categorized within one of four discipline areas: physics, biology, risk assessment, and microgravity. Topic areas within each discipline were assigned as follows: Physics - atomic physics, nuclear science, space radiation, radiation transport and shielding, and instrumentation; Biology - molecular biology, cellular radiation biology, tissue, organs and organisms, radioprotectants, and plants; Risk assessment - radiation health and epidemiology, space flight radiation health physics, inter- and intraspecies extrapolation, and radiation limits and standards; and Microgravity. When applicable subareas were assigned for selected topic areas. Keywords and author indices are provided.

  6. Radiation hydrodynamics integrated in the PLUTO code

    NASA Astrophysics Data System (ADS)

    Kolb, Stefan M.; Stute, Matthias; Kley, Wilhelm; Mignone, Andrea

    2013-11-01

    Aims: The transport of energy through radiation is very important in many astrophysical phenomena. In dynamical problems the time-dependent equations of radiation hydrodynamics have to be solved. We present a newly developed radiation-hydrodynamics module specifically designed for the versatile magnetohydrodynamic (MHD) code PLUTO. Methods: The solver is based on the flux-limited diffusion approximation in the two-temperature approach. All equations are solved in the co-moving frame in the frequency-independent (gray) approximation. The hydrodynamics is solved by the different Godunov schemes implemented in PLUTO, and for the radiation transport we use a fully implicit scheme. The resulting system of linear equations is solved either using the successive over-relaxation (SOR) method (for testing purposes) or using matrix solvers that are available in the PETSc library. We state in detail the methodology and describe several test cases to verify the correctness of our implementation. The solver works in standard coordinate systems, such as Cartesian, cylindrical, and spherical, and also for non-equidistant grids. Results: We present a new radiation-hydrodynamics solver coupled to the MHD-code PLUTO that is a modern, versatile, and efficient new module for treating complex radiation hydrodynamical problems in astrophysics. As test cases, either purely radiative situations, or full radiation-hydrodynamical setups (including radiative shocks and convection in accretion disks) were successfully studied. The new module scales very well on parallel computers using MPI. For problems in star or planet formation, we added the possibility of irradiation by a central source.

  7. Standard interface file handbook

    SciTech Connect

    Shapiro, A.; Huria, H.C. )

    1992-10-01

    This handbook documents many of the standard interface file formats that have been adopted by the US Department of Energy to facilitate communications between and portability of, various large reactor physics and radiation transport software packages. The emphasis is on those files needed for use of the VENTURE/PC diffusion-depletion code system. File structures, contents and some practical advice on use of the various files are provided.

  8. Setting Environmental Standards

    ERIC Educational Resources Information Center

    Fishbein, Gershon

    1975-01-01

    Recent court decisions have pointed out the complexities involved in setting environmental standards. Environmental health is composed of multiple causative agents, most of which work over long periods of time. This makes the cause-and-effect relationship between health statistics and environmental contaminant exposures difficult to prove in…

  9. 24 CFR 51.203 - Safety standards.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... from a hazard: (a) Thermal Radiation Safety Standard. Projects shall be located so that: (1) The allowable thermal radiation flux level at the building shall not exceed 10,000 BTU/sq. ft. per hr.; (2) The allowable thermal radiation flux level for outdoor, unprotected facilities or areas of congregation...

  10. Video Display Terminals: Radiation Issues.

    ERIC Educational Resources Information Center

    Murray, William E.

    1985-01-01

    Discusses information gathered in past few years related to health effects of video display terminals (VDTs) with particular emphasis given to issues raised by VDT users. Topics covered include radiation emissions, health concerns, radiation surveys, occupational radiation exposure standards, and long-term risks. (17 references) (EJS)

  11. Standardized Radiation Shield Design Methods: 2005 HZETRN

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Tripathi, Ram K.; Badavi, Francis F.; Cucinotta, Francis A.

    2006-01-01

    Research committed by the Langley Research Center through 1995 resulting in the HZETRN code provides the current basis for shield design methods according to NASA STD-3000 (2005). With this new prominence, the database, basic numerical procedures, and algorithms are being re-examined with new methods of verification and validation being implemented to capture a well defined algorithm for engineering design processes to be used in this early development phase of the Bush initiative. This process provides the methodology to transform the 1995 HZETRN research code into the 2005 HZETRN engineering code to be available for these early design processes. In this paper, we will review the basic derivations including new corrections to the codes to insure improved numerical stability and provide benchmarks for code verification.

  12. Radiation sickness

    MedlinePlus

    ... to determine the amount of radiation exposure from nuclear accidents, the best signs of the severity of the ... doses of radiation, such as radiation from a nuclear power plant accident Exposure to excessive radiation for medical treatments

  13. Radiation dosimetry.

    PubMed Central

    Cameron, J

    1991-01-01

    This article summarizes the basic facts about the measurement of ionizing radiation, usually referred to as radiation dosimetry. The article defines the common radiation quantities and units; gives typical levels of natural radiation and medical exposures; and describes the most important biological effects of radiation and the methods used to measure radiation. Finally, a proposal is made for a new radiation risk unit to make radiation risks more understandable to nonspecialists. PMID:2040250

  14. Many-body radiative heat transfer theory.

    PubMed

    Ben-Abdallah, Philippe; Biehs, Svend-Age; Joulain, Karl

    2011-09-01

    In this Letter, an N-body theory for the radiative heat exchange in thermally nonequilibrated discrete systems of finite size objects is presented. We report strong exaltation effects of heat flux which can be explained only by taking into account the presence of many-body interactions. Our theory extends the standard Polder and van Hove stochastic formalism used to evaluate heat exchanges between two objects isolated from their environment to a collection of objects in mutual interaction. It gives a natural theoretical framework to investigate the photon heat transport properties of complex systems at the mesoscopic scale. PMID:22026672

  15. Speech processing standards

    NASA Astrophysics Data System (ADS)

    Ince, A. Nejat

    1990-05-01

    Speech processing standards are given for 64, 32, 16 kb/s and lower rate speech and more generally, speech-band signals which are or will be promulgated by CCITT and NATO. The International Telegraph and Telephone Consultative Committee (CCITT) of the International body which deals, among other things, with speech processing within the context of ISDN. Within NATO there are also bodies promulgating standards which make interoperability, possible without complex and expensive interfaces. Some of the applications for low-bit rate voice and the related work undertaken by CCITT Study Groups which are responsible for developing standards in terms of encoding algorithms, codec design objectives as well as standards on the assessment of speech quality, are highlighted.

  16. EOS standards

    SciTech Connect

    Greeff, Carl W

    2011-01-12

    An approach to creating accurate EOS for pressure standards is described. Applications to Cu, Au, and Ta are shown. Extension of the method to high compressions using DFT is illustrated. Comparisons with modern functionals show promise.

  17. Networking standards

    NASA Technical Reports Server (NTRS)

    Davies, Mark

    1991-01-01

    The enterprise network is currently a multivendor environment consisting of many defacto and proprietary standards. During the 1990s, these networks will evolve towards networks which are based on international standards in both Local Area Network (LAN) and Wide Area Network (WAN) space. Also, you can expect to see the higher level functions and applications begin the same transition. Additional information is given in viewgraph form.

  18. (Terminology standardization)

    SciTech Connect

    Strehlow, R.A.

    1990-10-19

    Terminological requirements in information management was but one of the principal themes of the 2nd Congress on Terminology and Knowledge Engineering. The traveler represented the American Society for Testing and Materials' Committee on Terminology, of which he is the Chair. The traveler's invited workshop emphasized terminology standardization requirements in databases of material properties as well as practical terminology standardizing methods. The congress included six workshops in addition to approximately 82 lectures and papers from terminologists, artificial intelligence practitioners, and subject specialists from 18 countries. There were approximately 292 registrants from 33 countries who participated in the congress. The congress topics were broad. Examples were the increasing use of International Standards Organization (ISO) Standards in legislated systems such as the USSR Automated Data Bank of Standardized Terminology, the enhanced Physics Training Program based on terminology standardization in Physics in the Chinese province of Inner Mongolia, and the technical concept dictionary being developed at the Japan Electronic Dictionary Research Institute, which is considered to be the key to advanced artificial intelligence applications. The more usual roles of terminology work in the areas of machine translation. indexing protocols, knowledge theory, and data transfer in several subject specialties were also addressed, along with numerous special language terminology areas.

  19. ARM Standards Policy Committee Report

    SciTech Connect

    Cialella, A; Jensen, M; Koontz, A; McFarlane, S; McCoy, R; Monroe, J; Palanisamy, G; Perez, R; Sivaraman, C

    2012-09-19

    Data and metadata standards promote the consistent recording of information and are necessary to ensure the stability and high quality of Atmospheric Radiation Measurement (ARM) Climate Research Facility data products for scientific users. Standards also enable automated routines to be developed to examine data, which leads to more efficient operations and assessment of data quality. Although ARM Infrastructure agrees on the utility of data and metadata standards, there is significant confusion over the existing standards and the process for allowing the release of new data products with exceptions to the standards. The ARM Standards Policy Committee was initiated in March 2012 to develop a set of policies and best practices for ARM data and metadata standards.

  20. Disentangling the complex evolutionary history of the Western Palearctic blue tits (Cyanistes spp.) - phylogenomic analyses suggest radiation by multiple colonization events and subsequent isolation.

    PubMed

    Stervander, Martin; Illera, Juan Carlos; Kvist, Laura; Barbosa, Pedro; Keehnen, Naomi P; Pruisscher, Peter; Bensch, Staffan; Hansson, Bengt

    2015-05-01

    Isolated islands and their often unique biota continue to play key roles for understanding the importance of drift, genetic variation and adaptation in the process of population differentiation and speciation. One island system that has inspired and intrigued evolutionary biologists is the blue tit complex (Cyanistes spp.) in Europe and Africa, in particular the complex evolutionary history of the multiple genetically distinct taxa of the Canary Islands. Understanding Afrocanarian colonization events is of particular importance because of recent unconventional suggestions that these island populations acted as source of the widespread population in mainland Africa. We investigated the relationship between mainland and island blue tits using a combination of Sanger sequencing at a population level (20 loci; 12 500 nucleotides) and next-generation sequencing of single population representatives (>3 200 000 nucleotides), analysed in coalescence and phylogenetic frameworks. We found (i) that Afrocanarian blue tits are monophyletic and represent four major clades, (ii) that the blue tit complex has a continental origin and that the Canary Islands were colonized three times, (iii) that all island populations have low genetic variation, indicating low long-term effective population sizes and (iv) that populations on La Palma and in Libya represent relicts of an ancestral North African population. Further, demographic reconstructions revealed (v) that the Canary Islands, conforming to traditional views, hold sink populations, which have not served as source for back colonization of the African mainland. Our study demonstrates the importance of complete taxon sampling and an extensive multimarker study design to obtain robust phylogeographical inferences. PMID:25753616

  1. Evaluation of Arctic Broadband Surface Radiation Measurements

    SciTech Connect

    Matsui, N.; Long, Charles N.; Augustine, J. A.; Halliwell, D.; Uttal, Taneil; Longenecker, D.; Niebergale, J.; Wendell, J.; Albee, R.

    2012-02-24

    The Arctic is a challenging environment for making in-situ radiation measurements. A standard suite of radiation sensors is typically designed to measure the total, direct and diffuse components of incoming and outgoing broadband shortwave (SW) and broadband thermal infrared, or longwave (LW) radiation. Enhancements can include various sensors for measuring irradiance in various narrower bandwidths. Many solar radiation/thermal infrared flux sensors utilize protective glass domes and some are mounted on complex mechanical platforms (solar trackers) that rotate sensors and shading devices that track the sun. High quality measurements require striking a balance between locating sensors in a pristine undisturbed location free of artificial blockage (such as buildings and towers) and providing accessibility to allow operators to clean and maintain the instruments. Three significant sources of erroneous data include solar tracker malfunctions, rime/frost/snow deposition on the instruments and operational problems due to limited operator access in extreme weather conditions. In this study, a comparison is made between the global and component sum (direct [vertical component] + diffuse) shortwave measurements. The difference between these two quantities (that theoretically should be zero) is used to illustrate the magnitude and seasonality of radiation flux measurement problems. The problem of rime/frost/snow deposition is investigated in more detail for one case study utilizing both shortwave and longwave measurements. Solutions to these operational problems are proposed that utilize measurement redundancy, more sophisticated heating and ventilation strategies and a more systematic program of operational support and subsequent data quality protocols.

  2. Evaluation of Arctic broadband surface radiation measurements

    NASA Astrophysics Data System (ADS)

    Matsui, N.; Long, C. N.; Augustine, J.; Halliwell, D.; Uttal, T.; Longenecker, D.; Niebergall, O.; Wendell, J.; Albee, R.

    2012-02-01

    The Arctic is a challenging environment for making in-situ surface radiation measurements. A standard suite of radiation sensors is typically designed to measure incoming and outgoing shortwave (SW) and thermal infrared, or longwave (LW), radiation. Enhancements may include various sensors for measuring irradiance in narrower bandwidths. Many solar radiation/thermal infrared flux sensors utilize protective glass domes and some are mounted on complex mechanical platforms (solar trackers) that keep sensors and shading devices trained on the sun along its diurnal path. High quality measurements require striking a balance between locating stations in a pristine undisturbed setting free of artificial blockage (such as from buildings and towers) and providing accessibility to allow operators to clean and maintain the instruments. Three significant sources of erroneous data in the Arctic include solar tracker malfunctions, rime/frost/snow deposition on the protective glass domes of the radiometers and operational problems due to limited operator access in extreme weather conditions. In this study, comparisons are made between the global and component sum (direct [vertical component] + diffuse) SW measurements. The difference between these two quantities (that theoretically should be zero) is used to illustrate the magnitude and seasonality of arctic radiation flux measurement problems. The problem of rime/frost/snow deposition is investigated in more detail for one case study utilizing both SW and LW measurements. Solutions to these operational problems that utilize measurement redundancy, more sophisticated heating and ventilation strategies and a more systematic program of operational support and subsequent data quality protocols are proposed.

  3. Evaluation of arctic broadband surface radiation measurements

    NASA Astrophysics Data System (ADS)

    Matsui, N.; Long, C. N.; Augustine, J.; Halliwell, D.; Uttal, T.; Longenecker, D.; Nievergall, O.; Wendell, J.; Albee, R.

    2011-08-01

    The Arctic is a challenging environment for making in-situ radiation measurements. A standard suite of radiation sensors is typically designed to measure the total, direct and diffuse components of incoming and outgoing broadband shortwave (SW) and broadband thermal infrared, or longwave (LW) radiation. Enhancements can include various sensors for measuring irradiance in various narrower bandwidths. Many solar radiation/thermal infrared flux sensors utilize protective glass domes and some are mounted on complex mechanical platforms (solar trackers) that rotate sensors and shading devices that track the sun. High quality measurements require striking a balance between locating sensors in a pristine undisturbed location free of artificial blockage (such as buildings and towers) and providing accessibility to allow operators to clean and maintain the instruments. Three significant sources of erroneous data include solar tracker malfunctions, rime/frost/snow deposition on the instruments and operational problems due to limited operator access in extreme weather conditions. In this study, a comparison is made between the global and component sum (direct [vertical component] + diffuse) shortwave measurements. The difference between these two quantities (that theoretically should be zero) is used to illustrate the magnitude and seasonality of radiation flux measurement problems. The problem of rime/frost/snow deposition is investigated in more detail for one case study utilizing both shortwave and longwave measurements. Solutions to these operational problems are proposed that utilize measurement redundancy, more sophisticated heating and ventilation strategies and a more systematic program of operational support and subsequent data quality protocols.

  4. Randomized Phase III Trial to Test Accelerated Versus Standard Fractionation in Combination With Concurrent Cisplatin for Head and Neck Carcinomas in the Radiation Therapy Oncology Group 0129 Trial: Long-Term Report of Efficacy and Toxicity

    PubMed Central

    Nguyen-Tan, Phuc Felix; Zhang, Qiang; Ang, K. Kian; Weber, Randal S.; Rosenthal, David I.; Soulieres, Denis; Kim, Harold; Silverman, Craig; Raben, Adam; Galloway, Thomas J.; Fortin, André; Gore, Elizabeth; Westra, William H.; Chung, Christine H.; Jordan, Richard C.; Gillison, Maura L.; List, Marcie; Le, Quynh-Thu

    2014-01-01

    Purpose We tested the efficacy and toxicity of cisplatin plus accelerated fractionation with a concomitant boost (AFX-C) versus standard fractionation (SFX) in locally advanced head and neck carcinoma (LA-HNC). Patients and Methods Patients had stage III to IV carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx. Radiation therapy schedules were 70 Gy in 35 fractions over 7 weeks (SFX) or 72 Gy in 42 fractions over 6 weeks (AFX-C). Cisplatin doses were 100 mg/m2 once every 3 weeks for two (AFX-C) or three (SFX) cycles. Toxicities were scored by using National Cancer Institute Common Toxicity Criteria 2.0 and the Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer criteria. Overall survival (OS) and progression-free survival (PFS) rates were estimated by using the Kaplan-Meier method and were compared by using the one-sided log-rank test. Locoregional failure (LRF) and distant metastasis (DM) rates were estimated by using the cumulative incidence method and Gray's test. Results In all, 721 of 743 patients were analyzable (361, SFX; 360, AFX-C). At a median follow-up of 7.9 years (range, 0.3 to 10.1 years) for 355 surviving patients, no differences were observed in OS (hazard ratio [HR], 0.96; 95% CI, 0.79 to 1.18; P = .37; 8-year survival, 48% v 48%), PFS (HR, 1.02; 95% CI, 0.84 to 1.24; P = .52; 8-year estimate, 42% v 41%), LRF (HR, 1.08; 95% CI, 0.84 to 1.38; P = .78; 8-year estimate, 37% v 39%), or DM (HR, 0.83; 95% CI, 0.56 to 1.24; P = .16; 8-year estimate, 15% v 13%). For oropharyngeal cancer, p16-positive patients had better OS than p16-negative patients (HR, 0.30; 95% CI, 0.21 to 0.42; P < .001; 8-year survival, 70.9% v 30.2%). There were no statistically significant differences in the grade 3 to 5 acute or late toxicities between the two arms and p-16 status. Conclusion When combined with cisplatin, AFX-C neither improved outcome nor increased late toxicity in patients with LA-HNC. Long-term high survival

  5. Phosphorescence or Thermally Activated Delayed Fluorescence? Intersystem Crossing and Radiative Rate Constants of a Three-Coordinate Copper(I) Complex Determined by Quantum-Chemical Methods.

    PubMed

    Föller, Jelena; Kleinschmidt, Martin; Marian, Christel M

    2016-08-01

    The photophysical properties of a cationic three-coordinate copper(I) complex with a monodentate N-heterocyclic carbene ligand and a bidentate phenanthroline ligand have been investigated by employing computational chemistry methods. The absorption spectrum, calculated with the combined density functional theory and multireference configuration interaction method, matches experimentally available data perfectly, thus corroborating the validity of our applied theoretical approach. On the basis of our calculated singlet-triplet gap of 650 cm(-1) and the (reverse) intersystem crossing rates that are both larger than the fluorescence and phosphorescence rates at room temperature, we conclude that thermally activated delayed fluorescence should be observable for this complex in addition to phosphorescence. Torsion of the ligands has only a small impact on the singlet-triplet gap. However, the electronic coupling between the S1 and T1 states-and hence the probability for (reverse) intersystem crossing-is seen to increase substantially when moving from a coplanar to a perpendicular arrangement of the ligands. PMID:27428010

  6. The standard model

    SciTech Connect

    Marciano, W.J.

    1994-03-01

    In these lectures, my aim is to provide a survey of the standard model with emphasis on its renormalizability and electroweak radiative corrections. Since this is a school, I will try to be somewhat pedagogical by providing examples of loop calculations. In that way, I hope to illustrate some of the commonly employed tools of particle physics. With those goals in mind, I have organized my presentations as follows: In Section 2, renormalization is discussed from an applied perspective. The technique of dimensional regularization is described and used to define running couplings and masses. The utility of the renormalization group for computing leading logs is illustrated for the muon anomalous magnetic moment. In Section 3 electroweak radiative corrections are discussed. Standard model predictions are surveyed and used to constrain the top quark mass. The S, T, and U parameters are introduced and employed to probe for ``new physics``. The effect of Z{prime} bosons on low energy phenomenology is described. In Section 4, a detailed illustration of electroweak radiative corrections is given for atomic parity violation. Finally, in Section 5, I conclude with an outlook for the future.

  7. Variability of the infrared complex refractive index of African mineral dust: experimental estimation and implications for radiative transfer and satellite remote sensing

    NASA Astrophysics Data System (ADS)

    Di Biagio, C.; Boucher, H.; Caquineau, S.; Chevaillier, S.; Cuesta, J.; Formenti, P.

    2014-10-01

    radiative transfer (mass extinction efficiency, kext, single scattering albedo, ω, and asymmetry factor, g) have been calculated, by using the Mie theory, based on the estimated refractive index and measured particle size distribution. The optical properties show a large sample-to-sample variability, with kext, ω, and g varying in the range 0.05-0.35, 0.25-1.0, and 0.05-0.75. This variability is expected to significantly impact satellite retrievals of atmospheric and surface parameters (e.g. from the Infrared Atmospheric Sounding Interferometer, IASI) and estimates of the dust radiative forcing.

  8. Variability of the infrared complex refractive index of African mineral dust: experimental estimation and implications for radiative transfer and satellite remote sensing

    NASA Astrophysics Data System (ADS)

    Di Biagio, C.; Boucher, H.; Caquineau, S.; Chevaillier, S.; Cuesta, J.; Formenti, P.

    2014-04-01

    Experimental estimations of the infrared refractive index of African mineral dust have been retrieved from laboratory measurements of particle transmission spectra in the wavelength range 2.5-25 μm. Five dust samples collected at Banizoumbou (Niger) and Tamanrasset (Algeria) during dust events originated from different Western Saharan and Sahelian areas have been investigated. The obtained real (n) and imaginary (k) parts of the refractive index for the different dust cases vary in the range 1.1-2.7 and 0.05-1.0, respectively, and appear to be strongly sensitive to the mineralogical composition of the particles, especially in the 8-12 μm and 17-25 μm spectral intervals. Dust absorption is controlled mainly by clays, and, in minor fraction, by quartz and Ca-rich minerals. Size distribution, and the coarse fraction in particular, plays also a role in determining the refractive index. Significant differences are obtained when comparing our results with existing experimental estimations available in the literature, and with the values of the OPAC (Optical Properties of Aerosols and Clouds) database. The different datasets appear comparable in magnitude, with our values of n and k falling in the range of variability of past studies. However, literature data fail in accurately reproducing the spectral signatures of main minerals, in particular clays, and they significantly overestimate the contribution of quartz. We also found that the real and the imaginary parts of the refractive index from part of literature studies do not verify Kramers-Kronig relations, thus resulting theoretically incorrect. The comparison between our results, from Western Africa, and literature data, from different locations in Europe, Africa, and the Caribbean, nonetheless, confirms the expected large variability of the infrared refractive index of dust, thus highlighting the necessity for an extended systematic investigation. Aerosol intensive optical properties relevant to radiative transfer

  9. Complexity in Picture Books

    ERIC Educational Resources Information Center

    Sierschynski, Jarek; Louie, Belinda; Pughe, Bronwyn

    2015-01-01

    One of the key requirements of Common Core State Standards (CCSS) in English Language Arts is that students are able to read and access complex texts across all grade levels. The CCSS authors emphasize both the limitations and lack of accuracy in the current CCSS model of text complexity, calling for the development of new frameworks. In response…

  10. Radiation Safety in Pediatric Orthopaedics.

    PubMed

    Caird, Michelle S

    2015-01-01

    Patients, surgeons, and staff are exposed to ionizing radiation in pediatric orthopaedic surgery from diagnostic studies and imaging associated with procedures. Estimating radiation dose to pediatric patients is based on complex algorithms and dose to surgeons and staff is based on dosimeter monitoring. Surgeons can decrease radiation exposure to patients with careful and thoughtful ordering of diagnostic studies and by minimizing exposure intraoperatively. Surgeon and staff radiation exposure can be minimized with educational programs, proper shielding and positioning intraoperatively, and prudent use of intraoperative imaging. Overall, better awareness among pediatric orthopaedic surgeons of our role in radiation exposure can lead to improvements in radiation safety. PMID:26049299

  11. Dark radiative inverse seesaw mechanism

    NASA Astrophysics Data System (ADS)

    Ahriche, Amine; Boucenna, Sofiane M.; Nasri, Salah

    2016-04-01

    We present a minimal model that simultaneously accounts for neutrino masses and the origin of dark matter (DM) and where the electroweak phase transition is strong enough to allow for electroweak baryogenesis. The Standard Model is enlarged with a Majorana fermion, three generations of chiral fermion pairs, and a single complex scalar that plays a central role in DM production and phenomenology, neutrino masses, and the strength of the phase transition. All the new fields are singlets under the SM gauge group. Neutrino masses are generated via a new variant of the radiative inverse seesaw mechanism, where the required small mass term is generated via loops involving DM and no large hierarchy is assumed among the mass scales. The model offers all the advantage of low-scale neutrino mass models as well as a viable dark matter candidate that is testable with direct detection experiments.

  12. 30 CFR 57.5066 - Maintenance standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Maintenance standards. 57.5066 Section 57.5066... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Air Quality, Radiation... Maintenance standards. (a) Any diesel powered equipment operated at any time in underground areas must...

  13. 40 CFR 192.02 - Standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Standards. 192.02 Section 192.02 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS Standards for the...

  14. 40 CFR 192.02 - Standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Standards. 192.02 Section 192.02 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS Standards for the...

  15. 40 CFR 192.02 - Standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Standards. 192.02 Section 192.02 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS Standards for the...

  16. Pressure-induced changes of the vibrational modes of spin-crossover complexes studied by nuclear resonance scattering of synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Trautwein, A. X.; Paulsen, H.; Winkler, H.; Giefers, H.; Wortmann, G.; Toftlund, H.; Wolny, J. A.; Chumakov, A. I.; Leupold, O.

    2010-03-01

    Nuclear inelastic scattering (NIS) spectra were recorded for the spin-crossover complexes STP and ETP (STP = [Fe(1,1,1-tris{[N-(2-pyridylmethyl)-N-methylamino]methyl}-ethane)](ClO4)2 and ETP = [Fe(1,1,1-tris{[N-(2-pyridylmethyl)-N-methylamino]methyl}-butane)](ClO4)2) at 30 K and at room temperature and also at ambient pressure and applied pressure (up to 2.6 GPa). Spin transition from the high-spin (HS) to the low-spin (LS) state was observed by lowering temperature and also by applying pressure at room temperature and has been assigned to the hardening of iron-bond stretching modes due to the smaller volume in the LS isomer.

  17. DOE standard: Radiological control

    SciTech Connect

    Not Available

    1999-07-01

    The Department of Energy (DOE) has developed this Standard to assist line managers in meeting their responsibilities for implementing occupational radiological control programs. DOE has established regulatory requirements for occupational radiation protection in Title 10 of the Code of Federal Regulations, Part 835 (10 CFR 835), ``Occupational Radiation Protection``. Failure to comply with these requirements may lead to appropriate enforcement actions as authorized under the Price Anderson Act Amendments (PAAA). While this Standard does not establish requirements, it does restate, paraphrase, or cite many (but not all) of the requirements of 10 CFR 835 and related documents (e.g., occupational safety and health, hazardous materials transportation, and environmental protection standards). Because of the wide range of activities undertaken by DOE and the varying requirements affecting these activities, DOE does not believe that it would be practical or useful to identify and reproduce the entire range of health and safety requirements in this Standard and therefore has not done so. In all cases, DOE cautions the user to review any underlying regulatory and contractual requirements and the primary guidance documents in their original context to ensure that the site program is adequate to ensure continuing compliance with the applicable requirements. To assist its operating entities in achieving and maintaining compliance with the requirements of 10 CFR 835, DOE has established its primary regulatory guidance in the DOE G 441.1 series of Guides. This Standard supplements the DOE G 441.1 series of Guides and serves as a secondary source of guidance for achieving compliance with 10 CFR 835.

  18. Image Quality of 3rd Generation Spiral Cranial Dual-Source CT in Combination with an Advanced Model Iterative Reconstruction Technique: A Prospective Intra-Individual Comparison Study to Standard Sequential Cranial CT Using Identical Radiation Dose

    PubMed Central

    Wenz, Holger; Maros, Máté E.; Meyer, Mathias; Förster, Alex; Haubenreisser, Holger; Kurth, Stefan; Schoenberg, Stefan O.; Flohr, Thomas; Leidecker, Christianne; Groden, Christoph; Scharf, Johann; Henzler, Thomas

    2015-01-01

    Objectives To prospectively intra-individually compare image quality of a 3rd generation Dual-Source-CT (DSCT) spiral cranial CT (cCT) to a sequential 4-slice Multi-Slice-CT (MSCT) while maintaining identical intra-individual radiation dose levels. Methods 35 patients, who had a non-contrast enhanced sequential cCT examination on a 4-slice MDCT within the past 12 months, underwent a spiral cCT scan on a 3rd generation DSCT. CTDIvol identical to initial 4-slice MDCT was applied. Data was reconstructed using filtered backward projection (FBP) and 3rd-generation iterative reconstruction (IR) algorithm at 5 different IR strength levels. Two neuroradiologists independently evaluated subjective image quality using a 4-point Likert-scale and objective image quality was assessed in white matter and nucleus caudatus with signal-to-noise ratios (SNR) being subsequently calculated. Results Subjective image quality of all spiral cCT datasets was rated significantly higher compared to the 4-slice MDCT sequential acquisitions (p<0.05). Mean SNR was significantly higher in all spiral compared to sequential cCT datasets with mean SNR improvement of 61.65% (p*Bonferroni0.05<0.0024). Subjective image quality improved with increasing IR levels. Conclusion Combination of 3rd-generation DSCT spiral cCT with an advanced model IR technique significantly improves subjective and objective image quality compared to a standard sequential cCT acquisition acquired at identical dose levels. PMID:26288186

  19. Telemetry standards

    NASA Astrophysics Data System (ADS)

    1986-05-01

    The Telemetry Group (TG) of the Range Commanders Council (RCC) has prepared this document to foster the compatibility of telemetry transmitting, receiving, and signal processing equipment at all of the Test and Evaluation (T&E) ranges under the cognizance of the RCC. The Range Commanders highly recommend that telemetry equipment operated at the T&E ranges and telemetry equipment used by the range personnel in programs that require test range support, conform to these standards. These standards do not necessarily define the existing capability of any test range, but constitute a guide for the orderly implementation and application of telemetry systems for both the ranges and range users. The scope of capabilities attainable with the utilization of these standards requires a careful consideration of trade-offs. Guidance concerning these trade-offs is provided in the text. These standards provide the necessary criteria on which to base equipment design and modification. The ultimate purpose is to ensure an efficient spectrum and an interference-free operation of the radio link for telemetry systems at the RCC member ranges. etry systems at the RCC member ranges.

  20. 42 CFR 493.855 - Standard; Cytology: gynecologic examinations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Subspecialty for Laboratories Performing Tests of Moderate Complexity (including the Subcategory), High Complexity, Or Any Combination of These Tests § 493.855 Standard; Cytology: gynecologic examinations....

  1. Solving signal instability to maintain the second-order advantage in the resolution and determination of multi-analytes in complex systems by modeling liquid chromatography-mass spectrometry data using alternating trilinear decomposition method assisted with piecewise direct standardization.

    PubMed

    Gu, Hui-Wen; Wu, Hai-Long; Yin, Xiao-Li; Li, Shan-Shan; Liu, Ya-Juan; Xia, Hui; Xie, Li-Xia; Yu, Ru-Qin; Yang, Peng-Yuan; Lu, Hao-Jie

    2015-08-14

    The application of calibration transfer methods has been successful in combination with near-infrared spectroscopy or other tools for prediction of chemical composition. One of the developed methods that can provide accurate performances is the piecewise direct standardization (PDS) method, which in this paper is firstly applied to transfer from one day to another the second-order calibration model based on alternating trilinear decomposition (ATLD) method built for the interference-free resolution and determination of multi-analytes in complex systems by liquid chromatography-mass spectrometry (LC-MS) in full scan mode. This is an example of LC-MS analysis in which interferences have been found, making necessary the use of second-order calibration because of its capacity for modeling this phenomenon, which implies analytes of interest can be resolved and quantified even in the presence of overlapped peaks and unknown interferences. Once the second-order calibration model based on ATLD method was built, the calibration transfer was conducted to compensate for the signal instability of LC-MS instrument over time. This allows one to reduce the volume of the heavy works for complete recalibration which is necessary for later accurate determinations. The root-mean-square error of prediction (RMSEP) and average recovery were used to evaluate the performances of the proposed strategy. Results showed that the number of calibration samples used on the real LC-MS data was reduced by using the PDS method from 11 to 3 while producing comparable RMSEP values and recovery values that were statistically the same (F-test, 95% confidence level) to those obtained with 11 calibration samples. This methodology is in accordance with the highly recommended green analytical chemistry principles, since it can reduce the experimental efforts and cost with regard to the use of a new calibration model built in modified conditions. PMID:26141270

  2. The reaction of [Ir(C 3,N'-bpy) (bpy) 2] 2+ with OH radicals and radiation induced covalent binding of the complex to several polymers in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Behar, David; Neta, P.; Silverman, Joseph; Rabani, Joseph

    Irradiation of aqueous solutions of [Ir(C 3,N'-bpy) (bpy) 2] 2+ (IrP) produces a variety of OH adducts to IrP. The OH adducts decay by two second order processes separated in time. In the presence of both IrP and a soluble polymer, the OH radicals are shared between the IrP and the polymer, simultaneously producing OH adducts and polymer radicals. This is followed by radical-radical reactions. The rate constants of the various reactions between the OH adducts and the polymer radicals have been determined. The products of reactions of the OH adducts with polyethylene glycals (PEG .), polybrene radicals (PB .), and polystyrene sulfonate radicals (PSS .) are the respective polymers covalently linked to the iridium complex. This has been shown by dialysis as well as by spectral measurements. IrP behaves similarly to Ru (bpy) 2+3 which was studied before. This indicates that the radiation method may have a general use in the preparation of polymers with pendant bpy complexes.

  3. Auditing radiation sterilization facilities

    NASA Astrophysics Data System (ADS)

    Beck, Jeffrey A.

    The diversity of radiation sterilization systems available today places renewed emphasis on the need for thorough Quality Assurance audits of these facilities. Evaluating compliance with Good Manufacturing Practices is an obvious requirement, but an effective audit must also evaluate installation and performance qualification programs (validation_, and process control and monitoring procedures in detail. The present paper describes general standards that radiation sterilization operations should meet in each of these key areas, and provides basic guidance for conducting QA audits of these facilities.

  4. Evaluation of conductive, radiative, chemical, and convective heat transfer in complex systems using a fast-running, implicit, lumped-capacitance formulation

    SciTech Connect

    Benjamin, A.S.; Beraun, R.; Brown, N.N.; Sherman, M.P.

    1995-05-01

    Accurate finite-element simulation of 3-D nonlinear heat transfer in complex systems may require meshes composed of tens of thousands of finite elements and hours of CPU time on today`s fastest computers. To treat applications in which thousands of calculations may be necessary such as for risk assessment or design of high-temperature manufacturing processes, methods are needed which can solve these problems far more efficiently and maintain an acceptably high degree of accuracy. For this purpose, we developed the Thermal Evaluation and Matching Program for Risk Applications (TEMPRA). The primary differentiator between TEMPRA and comparable codes is its numerical formulation, which is designed to be unconditionally stable even with very large time steps, to afford good accuracy even with relatively coarse meshing, and to facilitate benchmarking/calibration through the use of adjustable parameters. Analysis for a sample problem shows that TEMPRA can obtain temperature response solutions with errors of less than 10% using approximately 1/1000 of the computer time required by a typical finite element code.

  5. RADIATION DOSIMETER

    DOEpatents

    Balkwell, W.R. Jr.; Adams, G.D. Jr.

    1960-05-10

    An improvement was made in the determination of amounts of ionizing radiation, particularly low-energy beta particles of less than 1000 rad total dose by means of fluid-phase dosimeter employing a stabilized-- sensitized ferrous-ferric colorimetric system in a sulphuric acid medium. The improvement in the dosimeter consists of adding to the ferrous-ferric system in concentrations of 10/sub -2/ to 10/sup -4/M an organic compound having one or more carboxylic or equivalent groups, such compounds being capable of chelating or complexing the iron ions in the solution. Suitable sensitizing and stabilizing agents are benzoic, phthalic, salicylic, malonic, lactic, maleic, oxalic, citric, succinic, phenolic tartaric, acetic, and adipic acid, as well as other compounds which are added to the solution alone or in certain combinations. As in conventional fluid-phase dosimeters, the absorbed dosage is correlated with a corresponding change in optical density at particular wavelengths of the solution.

  6. Radiation Therapy

    MedlinePlus

    Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from ... half of all cancer patients receive it. The radiation may be external, from special machines, or internal, ...

  7. Radiation therapy

    MedlinePlus

    Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells. ... faster than normal cells in the body. Because radiation is most harmful to quickly growing cells, radiation ...

  8. Radiation Therapy

    MedlinePlus

    Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them ... places inside your body. The type of radiation therapy you receive depends on many factors, including The ...

  9. Radiation Therapy

    MedlinePlus

    ... people who have radiation therapy may feel more tired than usual, not feel hungry, or lose their ... of radiation therapy include: Fatigue. Fatigue, or feeling tired, is the most common side effect of radiation ...

  10. Radiation Emergencies

    MedlinePlus

    ... day from sources such as sunlight. A radiation emergency would involve larger amounts of radiation and could ... are no guarantees of safety during a radiation emergency, you can take actions to protect yourself. You ...

  11. Estimation of a cosmonaut's radiation hazard during long-term space missions on the basis of a generalized dosimetric function.

    PubMed

    Shafirkin, A V; Petrov, V M

    2002-01-01

    This paper presents a new concept of radiation hazard assessment for spacecraft crew members during long term space missions on the basis of a generalized dosimetric function. This new dosimetric function enables a complicated nature of space radiation exposure to be reduced to the conditions of a standard irradiation. It can be obtained on the basis of mean-tissue equivalent dose values calculated for each space radiation source and transmission coefficients describing the influence of the complex spatial and temporal distribution of the absorbed dose in the cosmonaut's body on the radiobiological effects. The combination of cosmic ionizing radiation with other non-radiation nature factors in flight can also be accounted for. In terms of the generalized dose, it is possible to assess the nature and extent of lowering a crew working capacity, as well as radiation risk, both during a flight and post flight period. PMID:12539776

  12. Atmospheric radiation

    SciTech Connect

    Harshvardhan, M.R. )

    1991-01-01

    Studies of atmospheric radiative processes are summarized for the period 1987-1990. Topics discussed include radiation modeling; clouds and radiation; radiative effects in dynamics and climate; radiation budget and aerosol effects; and gaseous absorption, particulate scattering and surface reflection. It is concluded that the key developments of the period are a defining of the radiative forcing to the climate system by trace gases and clouds, the recognition that cloud microphysics and morphology need to be incorporated not only into radiation models but also climate models, and the isolation of a few important unsolved theoretical problems in atmospheric radiation.

  13. Radiation Hydrodynamics

    NASA Astrophysics Data System (ADS)

    Mihalas, Dimitri

    Basic Radiation Theory Specific Intensity Photon Number Density Photon Distribution Function Mean Intensity Radiation Energy Density Radiation Energy Flux Radiation Momentum Density Radiation Stress Tensor (Radiation Pressure Tensor) Thermal Radiation Thermodynamics of Thermal Radiation and a Perfect Gas The Transfer Equation Absorption, Emission, and Scattering The Equation of Transfer Moments of the Transfer Equation Lorentz Transformation of the Transfer Equation Lorentz Transformation of the Photon 4-Momentum Lorentz Transformation of the Specific Intensity, Opacity, and - Emissivity Lorentz Transformation of the Radiation Stress Energy Tensor The Radiation 4-Force Density Vector Covariant Form of the Transfer Equation Inertial-Frame Equations of Radiation Hydrodynamics Inertial-Frame Radiation Equations Inertial-Frame Equations of Radiation Hydrodynamics Comoving-Frame Equation of Transfer Special Relativistic Derivation (D. Mihalas) Consistency Between Comoving-Frame and Inertial-Frame Equations Noninertial Frame Derivation (J. I. Castor) Analysis of O (v/c) Terms Lagrangian Equations of Radiation Hydrodynamics Momentum Equation Gas Energy Equation First Law of Thermodynamics for the Radiation Field First Law of Thermodynamics for the Radiating Fluid Mechanical Energy Equation Total Energy Equation Consistency of Different Forms of the Radiating-Fluid Energy - and Momentum Equations Consistency of Inertial-Frame and Comoving-Frame Radiation Energy - and Momentum Equations Radiation Diffusion Radiation Diffusion Nonequilibrium Diffusion The Problem of Flux Limiting Shock Propagation: Numerical Methods Acoustic Waves Numerical Stability Systems of Equations Implications of Shock Development Implications of Diffusive Energy Transport Illustrative Example Numerical Radiation Hydrodynamics Radiating Fluid Energy and Momentum Equations Computational Strategy Energy Conservation Formal Solution Multigroup Equations An Astrophysical Example Adaptive-Grid Radiation

  14. Standards Laboratory environments

    SciTech Connect

    Braudaway, D.W.

    1990-09-01

    Standards Laboratory environments need to be carefully selected to meet the specific mission of each laboratory. The mission of the laboratory depends on the specific work supported, the measurement disciplines required and the level of uncertainty required in the measurements. This document reproduces the contents of the Sandia National Laboratories Primary Standards Laboratory Memorandum Number 3B (PSLM-3B) which was issued on May 16, 1988, under the auspices of the Department of Energy, Albuquerque Operations Office, to guide the laboratories of the Nuclear Weapons Complex in selecting suitable environments. Because of both general interest and specific interest in Standards Laboratory environments this document is being issued in a more available form. The purpose of this document is to provide guidance in selection of laboratory environments suitable for standards maintenance and calibration operations. It is not intended to mandate a specific environment for a specific calibration but to direct selection of the environment and to offer suggestions on how to extend precision in an existing and/or achievable (practical) environment. Although this documents pertains specifically to standards laboratories, it can be applied to any laboratory requiring environmental control.

  15. Isocurvature perturbations in extra radiation

    SciTech Connect

    Kawasaki, Masahiro; Miyamoto, Koichi; Nakayama, Kazunori; Sekiguchi, Toyokazu E-mail: miyamone@icrr.u-tokyo.ac.jp E-mail: oyokazu.sekiguchi@nagoya-u.jp

    2012-02-01

    Recent cosmological observations, including measurements of the CMB anisotropy and the primordial helium abundance, indicate the existence of an extra radiation component in the Universe beyond the standard three neutrino species. In this paper we explore the possibility that the extra radiation has isocurvatrue fluctuations. A general formalism to evaluate isocurvature perturbations in the extra radiation is provided in the mixed inflaton-curvaton system, where the extra radiation is produced by the decay of both scalar fields. We also derive constraints on the abundance of the extra radiation and the amount of its isocurvature perturbation. Current observational data favors the existence of an extra radiation component, but does not indicate its having isocurvature perturbation. These constraints are applied to some particle physics motivated models. If future observations detect isocurvature perturbations in the extra radiation, it will give us a hint to the origin of the extra radiation.

  16. Diffusion model for lightning radiative transfer

    NASA Technical Reports Server (NTRS)

    Koshak, William J.; Solakiewicz, Richard J.; Phanord, Dieudonne D.; Blakeslee, Richard J.

    1994-01-01

    A one-speed Boltzmann transport theory, with diffusion approximations, is applied to study the radiative transfer properties of lightning in optically thick thunderclouds. Near-infrared (lambda = 0.7774 micrometers) photons associated with a prominent oxygen emission triplet in the lightning spectrum are considered. Transient and spatially complex lightning radiation sources are placed inside a rectangular parallelepiped thundercloud geometry and the effects of multiple scattering are studied. The cloud is assumed to be composed of a homogeneous collection of identical spherical water droplets, each droplet a nearly conservative, anisotropic scatterer. Conceptually, we treat the thundercloud like a nuclear reactor, with photons replaced by neutrons, and utilize standard one-speed neutron diffusion techniques common in nuclear reactor analyses. Valid analytic results for the intensity distribution (expanded in spherical harmonics) are obtained for regions sufficiently far from sources. Model estimates of the arrival-time delay and pulse width broadening of lightning signals radiated from within the cloud are determined and the results are in good agreement with both experimental data and previous Monte Carlo estimates. Additional model studies of this kind will be used to study the general information content of cloud top lightning radiation signatures.

  17. Interdiction of Sphingolipid Metabolism to Improve Standard Cancer Therapies

    PubMed Central

    Beckham, Thomas H.; Cheng, Joseph C.; Marrison, S. Tucker; Norris, James S.; Liu, Xiang

    2014-01-01

    Non-surgical therapies for human malignancies must negotiate complex cell signaling pathways to impede cancer cell growth, ideally promoting death of cancer cells while sparing healthy tissue. For most of the past half century, medical approaches for treating cancer have relied primarily on cytotoxic chemotherapeutics that interfere with DNA replication and cell division, susceptibilities of rapidly dividing cancer cells. As a consequence, these therapies exert considerable cell stress, promoting the generation of ceramide through de novo synthesis and recycling of complex glycosphingolipids and sphingomyelin into apoptotic ceramide. Radiotherapy of cancer exerts similar geno- and cytotoxic cell stresses, and generation of ceramide following ionizing radiation therapy is a well-described feature of radiation-induced cell death. Emerging evidence now describes sphingolipids as mediators of death in response to newer targeted therapies, cementing ceramide generation as a common mechanism of cell death in response to cancer therapy. Many studies have now shown that dysregulation of ceramide accumulation—whether by reduced generation or accelerated metabolism—is a common mechanism of resistance to standard cancer therapies. The aims of this chapter will be to discuss described mechanisms of cancer resistance to therapy related to dysregulation of sphingolipid metabolism and to explore clinical and preclinical approaches to interdict sphingolipid metabolism to improve outcomes of standard cancer therapies. PMID:23290775

  18. Radiative interactions in nonequilibrium flows

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.; Chandrasekhar, R.

    1992-01-01

    The influence of vibrational and chemical nonequilibrium upon infrared radiative energy transfer in nonisothermal gases is investigated. Essential information is provided on rate equations, relaxation times, transfer equations, band absorption, and radiative flux equations. The methodology developed is applied to three specific cases. These are, absorbing-emitting species between isothermal parallel plates, radiating gases in the earth's atmosphere, and supersonic flow of premixed hydrogen and air in an expanding nozzle. The results obtained for different cases reveal that the extent of radiative interactions is reduced significantly under nonequilibrium conditions. The method developed can be easily extended to investigate radiative interactions in complex nonequilibrium flows.

  19. Pelvic radiation - discharge

    MedlinePlus

    Radiation of the pelvis - discharge; Cancer treatment - pelvic radiation; Prostate cancer - pelvic radiation; Ovarian cancer - pelvic radiation; Cervical cancer - pelvic radiation; Uterine cancer - pelvic radiation; Rectal cancer - ...

  20. Handover standards.

    PubMed

    2016-05-01

    An important part of discharge communication is the timely handover of information about diagnostic tests, as breakdown in this aspect of communication can contribute to unsafe patient care. NHS England has produced a set of standards to underpin the development of robust systems of care, policies and practice for the safe and high quality transfer of information about diagnostic tests and test results at discharge. The standards are governed by three overarching principles that have implications for nurses. They are that: ■ Clinicians who order tests are responsible for reviewing, acting on and communicating results and actions taken to GPs and patients, even if patients have been discharged. ■ Results received by GP practices should be reviewed and acted on by a responsible clinician even if they did not order the tests. ■ Reasonable adjustments should be made for people with learning disabilities and mental health problems and, where appropriate, families, carers, care co-ordinators and key workers should be invited to participate in handover processes and decisions about patients at discharge. PMID:27138516

  1. 40 CFR 197.20 - What standard must DOE meet?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA Public... committed effective dose equivalent from releases from the undisturbed Yucca Mountain disposal system:...

  2. 40 CFR 197.20 - What standard must DOE meet?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA Public... committed effective dose equivalent from releases from the undisturbed Yucca Mountain disposal system:...

  3. 40 CFR 197.20 - What standard must DOE meet?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA Public... committed effective dose equivalent from releases from the undisturbed Yucca Mountain disposal system:...

  4. 40 CFR 197.20 - What standard must DOE meet?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA Public... committed effective dose equivalent from releases from the undisturbed Yucca Mountain disposal system:...

  5. 40 CFR 197.30 - What standards must DOE meet?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA Public... of undisturbed performance after disposal, releases of radionuclides from waste in the Yucca...

  6. RADIOFREQUENCY RADIATION: ACTIVITIES AND ISSUES

    EPA Science Inventory

    The question of human safety relative to exposure to RF radiation obviously predates the first ANSI guideline established in 1966, but no enforceable Federal standards or guidelines exist for RF radiation exposure; the ANSI guideline which was revised in 1982 is voluntary or advi...

  7. The program RADLST (Radiation Listing)

    SciTech Connect

    Burrows, T.W.

    1988-02-29

    The program RADLST (Radiation Listing) is designed to calculate the nuclear and atomic radiations associated with the radioactive decay of nuclei. It uses as its primary input nuclear decay data in the Evaluated Nuclear Structure Data File (ENSDF) format. The code is written in FORTRAN 77 and, with a few exceptions, is consistent with the ANSI standard. 65 refs.

  8. Space Radiation Risk Assessment

    NASA Astrophysics Data System (ADS)

    Blakely, E.

    Evaluation of potential health effects from radiation exposure during and after deep space travel is important for the future of manned missions To date manned missions have been limited to near-Earth orbits with the moon our farthest distance from earth Historical space radiation career exposures for astronauts from all NASA Missions show that early missions involved total exposures of less than about 20 mSv With the advent of Skylab and Mir total career exposure levels increased to a maximum of nearly 200 mSv Missions in deep space with the requisite longer duration of the missions planned may pose greater risks due to the increased potential for exposure to complex radiation fields comprised of a broad range of radiation types and energies from cosmic and unpredictable solar sources The first steps in the evaluation of risks are underway with bio- and physical-dosimetric measurements on both commercial flight personnel and international space crews who have experience on near-earth orbits and the necessary theoretical modeling of particle-track traversal per cell including the contributing effects of delta-rays in particle exposures An assumption for biologic effects due to exposure of radiation in deep space is that they differ quantitatively and qualitatively from that on earth The dose deposition and density pattern of heavy charged particles are very different from those of sparsely ionizing radiation The potential risks resulting from exposure to radiation in deep space are cancer non-cancer and genetic effects Radiation from

  9. 10 CFR 20.1101 - Radiation protection programs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Radiation protection programs. 20.1101 Section 20.1101 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Radiation Protection Programs § 20.1101 Radiation protection programs. (a) Each licensee shall develop, document, and implement a radiation protection program...

  10. The beryllium "double standard" standard.

    PubMed

    Egilman, David S; Bagley, Sarah; Biklen, Molly; Golub, Alison Stern; Bohme, Susanna Rankin

    2003-01-01

    Brush Wellman, the world's leading producer and supplier of beryllium products, has systematically hidden cases of beryllium disease that occurred below the threshold limit value (TLV) and lied about the efficacy of the TLV in published papers, lectures, reports to government agencies, and instructional materials prepared for customers and workers. Hypocritically, Brush Wellman instituted a zero exposure standard for corporate executives while workers and customers were told the 2 microgram standard was "safe." Brush intentionally used its workers as "canaries for the plant," and referred to them as such. Internal documents and corporate depositions indicate that these actions were intentional and that the motive was money. Despite knowledge of the inadequacy of the TLV, Brush has successfully used it as a defense against lawsuits brought by injured workers and as a sales device to provide reassurance to customers. Brush's policy has reaped an untold number of victims and resulted in mass distribution of beryllium in consumer products. Such corporate malfeasance is perpetuated by the current market system, which is controlled by an organized oligopoly that creates an incentive for the neglect of worker health and safety in favor of externalizing costs to victimized workers, their families, and society at large. PMID:14758859

  11. US Food and Drug Administration Regulation of Medical Devices and Radiation Oncology: Can Reform Improve Safety?

    PubMed Central

    Hattangadi, Jona A.; O'Reilly, James T.; Recht, Abram

    2012-01-01

    Although radiation therapy is highly safe and effective in treating cancer, recent reports of dangerous radiation-related errors have focused a national spotlight on the field of radiation oncology and, more specifically, on the rapidly evolving and complex nature of radiation devices and how they are regulated. The purpose of this review is to explore the issues involved in medical device regulation in radiation oncology. We start with a general review of federal medical device regulation, including explanations of the legal and regulatory framework, and then discuss issues specific to radiation oncology with real-world examples. We also provide our thoughts on potential solutions and reforms to the current system, including better reporting of radiation-related errors in a centralized database, well-defined criteria for establishing substantial equivalence of a new device, and standard postmarket surveillance of radiation devices. Modern radiation therapy is a powerful tool that can help cure many patients' cancers and alleviate others' suffering with limited adverse effects. We must ensure that this promise is never compromised by avoidable mistakes. PMID:22548012

  12. Survivors and scientists: Hiroshima, Fukushima, and the Radiation Effects Research Foundation, 1975-2014.

    PubMed

    Lindee, Susan

    2016-04-01

    In this article, I reflect on the Radiation Effects Research Foundation and its ongoing studies of long-term radiation risk. Originally called the Atomic Bomb Casualty Commission (1947-1975), the Radiation Effects Research Foundation has carried out epidemiological research tracking the biomedical effects of radiation at Hiroshima and Nagasaki for almost 70 years. Radiation Effects Research Foundation scientists also played a key role in the assessment of populations exposed at Chernobyl and are now embarking on studies of workers at the Fukushima Daiichi Nuclear Power Plant. I examine the role of estimating dosimetry in post-disaster epidemiology, highlight how national identity and citizenship have mattered in radiation risk networks, and track how participants interpreted the relationships between nuclear weapons and nuclear energy. Industrial interests in Japan and the United States sought to draw a sharp line between the risks of nuclear war and the risks of nuclear power, but the work of the Radiation Effects Research Foundation (which became the basis of worker protection standards for the industry) and the activism of atomic bomb survivors have drawn these two nuclear domains together. This is so particularly in the wake of the Fukushima disaster, Japan's 'third atomic bombing'. The Radiation Effects Research Foundation is therefore a critical node in a complex global network of scientific institutions that adjudicate radiation risk and proclaim when it is present and when absent. Its history, I suggest, can illuminate some properties of modern disasters and the many sciences that engage with them. PMID:27263236

  13. Common Core State Standards and Adaptive Teaching

    ERIC Educational Resources Information Center

    Kamil, Michael L.

    2016-01-01

    This article examines the issues of how Common Core State Standards (CCSS) will impact adaptive teaching. It focuses on 2 of the major differences between conventional standards and CCSS: the increased complexity of text and the addition of disciplinary literacy standards to reading instruction. The article argues that adaptive teaching under CCSS…

  14. Standard atmosphere

    NASA Technical Reports Server (NTRS)

    Gregg, Willis Ray

    1923-01-01

    This report was prepared at the request of the National Advisory Committee for Aeronautics and discusses the need of a standard set of values of pressure, temperature and density at various altitudes and points out the desirability of adopting such values as are most in accord with actual average conditions, in order that corrections in individual cases may be as small as possible. To meet this need, so far as the united states is concerned, all free-air observations obtained by means of kites and balloons at several stations in this country near latitude 40 degrees N., have been used, and average values of pressure, temperature, and density, based upon those observations, have been determined for summer, winter, and the year, and for all altitudes up to 20,000 meters (65,000 feet). These values are presented in tables and graphs in both metric and english units; and in the tables of densities there are also included values of density for other parts of the world, more particularly for Europe. A comparison with these values shows that, except in the lowest levels, the agreement is very satisfactory.

  15. Paediatric radiation oncology in the care of childhood cancer: A position paper by the International Paediatric Radiation Oncology Society (PROS).

    PubMed

    Kortmann, Rolf-Dieter; Freeman, Carolyn; Marcus, Karen; Claude, Line; Dieckmann, Karin; Halperin, Edward; Esiashvili, Natia; Paulino, Arnold; Mahajan, Anita; Seiersen, Klaus; Ahern, Verity; Ricardi, Umberto; Carrie, Christian

    2016-05-01

    Paediatric malignancies are a challenge for the radiation oncologist due to their rarity, the great variety of histological types, and the complexity of treatment concepts that evolve over time. The Paediatric Radiation Oncology Society (PROS) is the only internationally operating society for paediatric radiation oncology. The objectives of PROS are to set a world-wide standard of excellence with respect to radiation oncology aspects in curing children and adolescents with cancer, to provide a forum for communication between radiation oncologists, and to exchange information with all professionals involved in the management of paediatric and adolescent cancer. Challenges include the need to promote education and support practice in low and middle income countries (LMIC) as well as the cost and availability of modern treatment technologies for all but most especially these countries. Collaborations with other societies that include for example the education programmes provided jointly with ESTRO, and the upgraded technical platform of the PROS web site offer new possibilities to enhance the efficacy of PROS in education and support of paediatric radiation oncology practice world-wide. PROS has made an important contribution to the management of childhood malignancies over the past decade and new and developing collaborations between PROS and other societies or organizations will ultimately lead to a reduction in world-wide health care inequalities. PMID:27106553

  16. Radiation dosimetry and biophysical models of space radiation effects

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Wu, Honglu; Shavers, Mark R.; George, Kerry

    2003-01-01

    Estimating the biological risks from space radiation remains a difficult problem because of the many radiation types including protons, heavy ions, and secondary neutrons, and the absence of epidemiology data for these radiation types. Developing useful biophysical parameters or models that relate energy deposition by space particles to the probabilities of biological outcomes is a complex problem. Physical measurements of space radiation include the absorbed dose, dose equivalent, and linear energy transfer (LET) spectra. In contrast to conventional dosimetric methods, models of radiation track structure provide descriptions of energy deposition events in biomolecules, cells, or tissues, which can be used to develop biophysical models of radiation risks. In this paper, we address the biophysical description of heavy particle tracks in the context of the interpretation of both space radiation dosimetry and radiobiology data, which may provide insights into new approaches to these problems.

  17. Space Radiation

    NASA Technical Reports Server (NTRS)

    Wu, Honglu

    2006-01-01

    Astronauts receive the highest occupational radiation exposure. Effective protections are needed to ensure the safety of astronauts on long duration space missions. Increased cancer morbidity or mortality risk in astronauts may be caused by occupational radiation exposure. Acute and late radiation damage to the central nervous system (CNS) may lead to changes in motor function and behavior, or neurological disorders. Radiation exposure may result in degenerative tissue diseases (non-cancer or non-CNS) such as cardiac, circulatory, or digestive diseases, as well as cataracts. Acute radiation syndromes may occur due to occupational radiation exposure.

  18. Head Resistance Due to Radiators

    NASA Technical Reports Server (NTRS)

    Kleinschmidt, R V; Parsons, S R

    1920-01-01

    Part 1 deals with the head resistance of a number of common types of radiator cores at different speeds in free air, as measured in the wind tunnel at the bureau of standards. This work was undertaken to determine the characteristics of various types of radiator cores, and in particular to develop the best type of radiator for airplanes. Some 25 specimens of core were tested, including practically all the general types now in use, except the flat plate type. Part 2 gives the results of wind tunnel tests of resistance on a model fuselage with a nose radiator. Part 3 presents the results of preliminary tests of head resistance of a radiator enclosed in a streamlined casing. Special attention is given to the value of wing radiator and of the radiator located in the open, especially when it is provided with a properly designed streamlined casing.

  19. 40 CFR 192.22 - Supplemental standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Supplemental standards. 192.22 Section 192.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS...

  20. 40 CFR 192.22 - Supplemental standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Supplemental standards. 192.22 Section 192.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS...

  1. 40 CFR 192.22 - Supplemental standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Supplemental standards. 192.22 Section 192.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS...

  2. 40 CFR 192.22 - Supplemental standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Supplemental standards. 192.22 Section 192.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS...

  3. 1991 annual book of ASTM standards

    SciTech Connect

    Not Available

    1991-01-01

    This book contains nuclear technology standards also features test methods and practices for solar and geotechnical energy. In the nuclear category, the primary emphasis of this volume is on analysis, dosimetry, and radiation effects in materials. Over eighty standards primarily test methods and practices are featured in this category.

  4. 40 CFR 192.22 - Supplemental standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Supplemental standards. 192.22 Section 192.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS...

  5. ISO WD 1856. Guideline for radiation exposure of nonmetallic materials. Present status

    NASA Astrophysics Data System (ADS)

    Briskman, B. A.

    In the framework of the International Organization for Standardization (ISO) activity we started development of international standard series for space environment simulation at on-ground tests of materials. The proposal was submitted to ISO Technical Committee 20 (Aircraft and Space Vehicles), Subcommittee 14 (Space Systems and Operations) and was approved as Working Draft 15856 at the Los-Angeles meeting (1997). A draft of the first international standard "Space Environment Simulation for Radiation Tests of Materials" (1st version) was presented at the 7th International Symposium on Materials in Space Environment (Briskman et al, 1997). The 2nd version of the standard was limited to nonmetallic materials and presented at the 20th Space Simulation Conference (Briskman and Borson, 1998). It covers the testing of nonmetallic materials embracing also polymer composite materials including metal components (metal matrix composites) to simulated space radiation. The standard does not cover semiconductor materials. The types of simulated radiation include charged particles (electrons and protons), solar ultraviolet radiation, and soft X-radiation of solar flares. Synergistic interactions of the radiation environment are covered only for these natural and some induced environmental effects. This standard outlines the recommended methodology and practices for the simulation of space radiation on materials. Simulation methods are used to reproduce the effects of the space radiation environment on materials that are located on surfaces of space vehicles and behind shielding. It was discovered that the problem of radiation environment simulation is very complex and the approaches of different specialists and countries to the problem are sometimes quite opposite. To the present moment we developed seven versions of the standard. The last version is a compromise between these approaches. It was approved at the last ISO TC20/SC14/WG4 meeting in Houston, October 2002. At a

  6. Radiative model of neutrino mass with neutrino interacting MeV dark matter

    NASA Astrophysics Data System (ADS)

    Arhrib, Abdesslam; Bœhm, Céline; Ma, Ernest; Yuan, Tzu-Chiang

    2016-04-01

    We consider the radiative generation of neutrino mass through the interactions of neutrinos with MeV dark matter. We construct a realistic renormalizable model with one scalar doublet (in additional to the standard model doublet) and one complex singlet together with three light singlet Majorana fermions, all transforming under a dark U(1)D symmetry which breaks softly to Z2. We study in detail the scalar sector which supports this specific scenario and its rich phenomenology.

  7. Radiation therapy

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/001918.htm Radiation therapy To use the sharing features on this page, please enable JavaScript. Radiation therapy uses high-powered x-rays, particles, or ...

  8. 14 CFR 25.1023 - Oil radiators.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Oil radiators. 25.1023 Section 25.1023... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Oil System § 25.1023 Oil radiators. (a) Each oil radiator must be able to withstand, without failure, any vibration, inertia, and oil pressure load to which...

  9. 14 CFR 23.1023 - Oil radiators.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Oil radiators. 23.1023 Section 23.1023... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Oil System § 23.1023 Oil radiators. Each oil radiator and its supporting structures must be able to withstand the vibration,...

  10. 14 CFR 23.1023 - Oil radiators.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Oil radiators. 23.1023 Section 23.1023... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Oil System § 23.1023 Oil radiators. Each oil radiator and its supporting structures must be able to withstand the vibration,...

  11. 14 CFR 25.1023 - Oil radiators.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Oil radiators. 25.1023 Section 25.1023... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Oil System § 25.1023 Oil radiators. (a) Each oil radiator must be able to withstand, without failure, any vibration, inertia, and oil pressure load to which...

  12. 14 CFR 29.1023 - Oil radiators.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Oil radiators. 29.1023 Section 29.1023... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Oil System § 29.1023 Oil radiators. (a) Each oil radiator must be able to withstand any vibration, inertia, and oil pressure loads to which it would...

  13. 14 CFR 29.1023 - Oil radiators.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Oil radiators. 29.1023 Section 29.1023... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Oil System § 29.1023 Oil radiators. (a) Each oil radiator must be able to withstand any vibration, inertia, and oil pressure loads to which it would...

  14. 14 CFR 25.1023 - Oil radiators.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Oil radiators. 25.1023 Section 25.1023... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Oil System § 25.1023 Oil radiators. (a) Each oil radiator must be able to withstand, without failure, any vibration, inertia, and oil pressure load to which...

  15. 14 CFR 23.1023 - Oil radiators.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Oil radiators. 23.1023 Section 23.1023... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Oil System § 23.1023 Oil radiators. Each oil radiator and its supporting structures must be able to withstand the vibration,...

  16. 14 CFR 25.1023 - Oil radiators.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Oil radiators. 25.1023 Section 25.1023... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Oil System § 25.1023 Oil radiators. (a) Each oil radiator must be able to withstand, without failure, any vibration, inertia, and oil pressure load to which...

  17. 14 CFR 25.1023 - Oil radiators.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Oil radiators. 25.1023 Section 25.1023... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Oil System § 25.1023 Oil radiators. (a) Each oil radiator must be able to withstand, without failure, any vibration, inertia, and oil pressure load to which...

  18. 14 CFR 23.1023 - Oil radiators.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Oil radiators. 23.1023 Section 23.1023... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Oil System § 23.1023 Oil radiators. Each oil radiator and its supporting structures must be able to withstand the vibration,...

  19. 14 CFR 29.1023 - Oil radiators.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Oil radiators. 29.1023 Section 29.1023... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Oil System § 29.1023 Oil radiators. (a) Each oil radiator must be able to withstand any vibration, inertia, and oil pressure loads to which it would...

  20. 14 CFR 29.1023 - Oil radiators.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Oil radiators. 29.1023 Section 29.1023... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Oil System § 29.1023 Oil radiators. (a) Each oil radiator must be able to withstand any vibration, inertia, and oil pressure loads to which it would...

  1. 14 CFR 23.1023 - Oil radiators.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Oil radiators. 23.1023 Section 23.1023... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Oil System § 23.1023 Oil radiators. Each oil radiator and its supporting structures must be able to withstand the vibration,...

  2. 14 CFR 29.1023 - Oil radiators.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Oil radiators. 29.1023 Section 29.1023... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Oil System § 29.1023 Oil radiators. (a) Each oil radiator must be able to withstand any vibration, inertia, and oil pressure loads to which it would...

  3. High Standards or a High Standard of Standardness?

    ERIC Educational Resources Information Center

    McWilliam, Erica

    2010-01-01

    This paper explores the difference between "high standards" and a "high standard of standardness" of professional service provision in teacher-librarianship. That is to say, it explores the difference between a demonstrated deep commitment to 21st century learning ("high standards") and demonstrated compliance with a pre-determined checklist of…

  4. [Radiation risk, health and quality of life: the medico-psychological and social-ecological aspects].

    PubMed

    Davydov, B I; Ponomarenko, V A; Baluev, O T; Ushakov, I B

    1993-01-01

    Complexity and contradictoriness of the triplet life quality-health-risk gain particular acuity owing to the extensive and intensive nature of radiation and non-radiation risks in the modern technological society. Improvement of life standards issue new risks. Unavoidability of existing risks, emergence of new ones, and necessity of qualitative, first of all energetic, life maintenance come into conflict with the principles of ecological stability. The concept of life quality is in many respects irrational and in the future will largely hinge on traditions, ideological and religious maxims. PMID:8012301

  5. Radiation physics, biophysics, and radiation biology

    SciTech Connect

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  6. Radiation Exposure

    MedlinePlus

    Radiation is energy that travels in the form of waves or high-speed particles. It occurs naturally in sunlight. Man-made radiation is used in X-rays, nuclear weapons, nuclear power plants and cancer treatment. If you are exposed to small amounts of radiation over a ...

  7. The standard model and colliders

    SciTech Connect

    Hinchliffe, I.

    1987-03-01

    Some topics in the standard model of strong and electroweak interactions are discussed, as well as how these topics are relevant for the high energy colliders which will become operational in the next few years. The radiative corrections in the Glashow-Weinberg-Salam model are discussed, stressing how these corrections may be measured at LEP and the SLC. CP violation is discussed briefly, followed by a discussion of the Higgs boson and the searches which are relevant to hadron colliders are then discussed. Some of the problems which the standard model does not solve are discussed, and the energy ranges accessible to the new colliders are indicated. (LEW)

  8. Cesium standard for satellite application

    NASA Technical Reports Server (NTRS)

    Bloch, M. B.; Meirs, M.; Pascaru, I.; Weinstein, B.

    1983-01-01

    A Cesium frequency standard that was developed for satellite applications is discussed. It weighs 23 lbs. and uses 23.5 watts of power, achieves a stability of 1 x ten to the minus 13th power/100,000 seconds, and is radiation hardened. To achieve the weight and reliability requirements, both thick and thin film hybrid circuits were utilized. A crystal oscillator is used to improve short-term stability and performance on a moving platform.

  9. 40 CFR 197.25 - What standard must DOE meet?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false What standard must DOE meet? 197.25 Section 197.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA...

  10. 40 CFR 197.25 - What standard must DOE meet?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false What standard must DOE meet? 197.25 Section 197.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA...

  11. 40 CFR 197.25 - What standard must DOE meet?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false What standard must DOE meet? 197.25 Section 197.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA...

  12. 40 CFR 197.25 - What standard must DOE meet?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false What standard must DOE meet? 197.25 Section 197.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA...

  13. Radiation proctopathy.

    PubMed

    Grodsky, Marc B; Sidani, Shafik M

    2015-06-01

    Radiation therapy is a widely utilized treatment modality for pelvic malignancies, including prostate cancer, rectal cancer, and cervical cancer. Given its fixed position in the pelvis, the rectum is at a high risk for injury secondary to ionizing radiation. Despite advances made in radiation science, up to 75% of the patients will suffer from acute radiation proctitis and up to 20% may experience chronic symptoms. Symptoms can be variable and include diarrhea, bleeding, incontinence, and fistulization. A multitude of treatment options exist. This article summarizes the latest knowledge relating to radiation proctopathy focusing on the vast array of treatment options. PMID:26034407

  14. Radiation hydrodynamics

    SciTech Connect

    Pomraning, G.C.

    1982-12-31

    This course was intended to provide the participant with an introduction to the theory of radiative transfer, and an understanding of the coupling of radiative processes to the equations describing compressible flow. At moderate temperatures (thousands of degrees), the role of the radiation is primarily one of transporting energy by radiative processes. At higher temperatures (millions of degrees), the energy and momentum densities of the radiation field may become comparable to or even dominate the corresponding fluid quantities. In this case, the radiation field significantly affects the dynamics of the fluid, and it is the description of this regime which is generally the charter of radiation hydrodynamics. The course provided a discussion of the relevant physics and a derivation of the corresponding equations, as well as an examination of several simplified models. Practical applications include astrophysics and nuclear weapons effects phenomena.

  15. Radiation Safety System for Stanford Synchrotron Radiation Laboratory

    SciTech Connect

    Liu, J

    2004-03-12

    Radiation Safety System (RSS) at the Stanford Synchrotron Radiation Laboratory is summarized and reviewed. The RSS, which is designed to protect people from prompt radiation hazards from accelerator operation, consists of the Access Control System (ACS) and the Beam Containment System (BCS). The ACS prevents people from being exposed to the lethal radiation level inside the shielding housing (called a PPS area at SLAC). The ACS for a PPS area consists of the shielding housing, beam inhibiting devices, and a standard entry module at each entrance. The BCS protects people from the prompt radiation hazards outside a PPS area under both normal and abnormal beam loss situations. The BCS consists of the active power (current/energy) limiting devices, beam stoppers, shielding, and an active radiation monitor system. The policies and practices in setting up the RSS at SLAC are illustrated.

  16. Complexity Survey.

    ERIC Educational Resources Information Center

    Gordon, Sandra L.; Anderson, Beth C.

    To determine whether consensus existed among teachers about the complexity of common classroom materials, a survey was administered to 66 pre-service and in-service kindergarten and prekindergarten teachers. Participants were asked to rate 14 common classroom materials as simple, complex, or super-complex. Simple materials have one obvious part,…

  17. Engineered and Administrative Safety Systems for the Control of Prompt Radiation Hazards at Accelerator Facilities

    SciTech Connect

    Liu, James C.; Vylet, Vashek; Walker, Lawrence S.; /SLAC

    2007-12-17

    The ANSI N43.1 Standard, currently in revision (ANSI 2007), sets forth the requirements for accelerator facilities to provide adequate protection for the workers, the public and the environment from the hazards of ionizing radiation produced during and from accelerator operations. The Standard also recommends good practices that, when followed, provide a level of radiation protection consistent with those established for the accelerator communities. The N43.1 Standard is suitable for all accelerator facilities (using electron, positron, proton, or ion particle beams) capable of producing radiation, subject to federal or state regulations. The requirements (see word 'shall') and recommended practices (see word 'should') are prescribed in a graded approach that are commensurate with the complexity and hazard levels of the accelerator facility. Chapters 4, 5 and 6 of the N43.1 Standard address specially the Radiation Safety System (RSS), both engineered and administrative systems, to mitigate and control the prompt radiation hazards from accelerator operations. The RSS includes the Access Control System (ACS) and Radiation Control System (RCS). The main requirements and recommendations of the N43.1 Standard regarding the management, technical and operational aspects of the RSS are described and condensed in this report. Clearly some aspects of the RSS policies and practices at different facilities may differ in order to meet the practical needs for field implementation. A previous report (Liu et al. 2001a), which reviews and summarizes the RSS at five North American high-energy accelerator facilities, as well as the RSS references for the 5 labs (Drozdoff 2001; Gallegos 1996; Ipe and Liu 1992; Liu 1999; Liu 2001b; Rokni 1996; TJNAF 1994; Yotam et al. 1991), can be consulted for the actual RSS implementation at various laboratories. A comprehensive report describing the RSS at the Stanford Linear Accelerator Center (SLAC 2006) can also serve as a reference.

  18. Thymic neoplasm: a rare disease with a complex clinical presentation

    PubMed Central

    Rashid, Omar M.; Cassano, Anthony D.

    2013-01-01

    Thymic neoplasms constitute a broad category of rare lesions with a wide spectrum of pathologic characteristics and clinical presentations which therefore require a high index of suspicion to diagnose. The natural history of the disease is seldom predictable, anywhere from an indolent to an aggressively malignant course. Although the classification and staging of these lesions are complex and controversial, complete radical surgical resection remains the gold standard of therapy. Radiation and chemotherapy are important elements of the multimodality approach to treating these patients and it is important for thoracic surgeons to work closely with their colleagues in other disciplines in the management of and future research endeavors in thymic neoplasm. In this review, we discuss the evaluation of the patient with an anterior mediastinal mass, the classification and staging of thymic neoplasms, the role of surgery, radiation and chemotherapy in treating this disease, as well as future directions in research for novel targeted therapies. PMID:23585946

  19. Communication complexity and information complexity

    NASA Astrophysics Data System (ADS)

    Pankratov, Denis

    Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

  20. Radiation Chemistry

    NASA Astrophysics Data System (ADS)

    Wojnárovits, L.

    Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.