WorldWideScience

Sample records for radiation detection functionality

  1. Detection of Terahertz Radiation

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a system for detecting terahertz radiation, a camera device, and a method for detecting terahertz radiation.......The present invention relates to a system for detecting terahertz radiation, a camera device, and a method for detecting terahertz radiation....

  2. Counterbalanced radiation detection system

    International Nuclear Information System (INIS)

    Platz, W.

    1987-01-01

    A counterbalanced radiation detection system is described comprising: (a) a stand; (b) a first radiation detector; (c) a first radiation detector arm means for tiltably connecting the first radiation detector with the stand; (d) a second radiation detector; (e) a second radiation detector arm means for tiltably connecting the second radiation detector with the stand, whereby the tilting angles of the radiation detector arm means define a distance between the radiation detectors; and (f) a torque transforming means connected between the first and second radiation detector arm means for transforming the torque created by one of the radiation detectors in a sense opposed to the torque created by the other radiation detector

  3. Counterbalanced radiation detection device

    International Nuclear Information System (INIS)

    Platz, W.

    1986-01-01

    A counterbalanced radiation detection device is described which consists of: (a) a base; (b) a radiation detector having a known weight; (c) means connected with the radiation detector and the base for positioning the radiation detector in different heights with respect to the base; (d) electronic component means movably mounted on the base for counterbalancing the weight of the radiation detector; (e) means connected with the electronic component means and the radiation detector positioning means for positioning the electronic component means in different heights with respect to the base opposite to the heights of the radiation detector; (f) means connected with the radiation detector and the base for shifting the radiation detector horizontally with respect to the base; and (g) means connected with the electronic component means and the radiation detector shifting means for shifting the electronic component means horizontally with respect to the base in opposite direction to shifting of the radiation detector

  4. Semiconductor radiation detection systems

    CERN Document Server

    2010-01-01

    Covers research in semiconductor detector and integrated circuit design in the context of medical imaging using ionizing radiation. This book explores other applications of semiconductor radiation detection systems in security applications such as luggage scanning, dirty bomb detection and border control.

  5. Radiation detection and measurement

    International Nuclear Information System (INIS)

    Knoll, G.F.

    1979-01-01

    The book is a complete, clear and up-to-date text that provides a basic review of instruments and methods of ionizing radiation. The text covers detailed discussion of all detector types introductory discussions of radiation sources, interactions, and counting statistics functional analysis of the electronics and pulse processing aspects of radiation detectors in instrumentation systems and consideration of shielding and background potentially vital in low-level counting. A total of 350 figures and approximately 900 references to current scientific literature is included. The book is largely intended as a textbook for a junior/senior or first-year graduate course in nuclear instrumentation and radiation measurements

  6. Radiation detection system

    International Nuclear Information System (INIS)

    Haeuszer, F.A.

    1976-01-01

    A circuit is disclosed that detects radiation transients and provides a clamping signal in response to each transient. The clamping signal is present from the time the transient rises above a given threshold level and for a known duration thereafter. The system includes radiation sensors, a blocking oscillator that generates a pulse in response to each sensor signal, and an output pulse duration control circuit. The oscillator pulses are fed simultaneously to the output pulse duration control circuit and to an OR gate, the output of which comprises the system output. The output pulse duration is controlled by the time required to magnetize a magnetic core to saturation in first one direction and then the other

  7. Radiation detection and measurement

    International Nuclear Information System (INIS)

    Knoll, G.F.

    1979-01-01

    Introductory material covers radiation sources, radiation interactions, general properties of radiation detectors, and counting statistics and error prediction. This is followed by detailed sections on gas-filled detectors, scintillation counters, semiconductor detectors, neutron detectors and spectroscopy, detector electronics and pulse processing, and miscellaneous radiation detectors and applications

  8. Measurement and detection of radiation

    National Research Council Canada - National Science Library

    Tsoulfanidis, Nicholas; Landsberger, Sheldon

    2011-01-01

    .... With the miniaturization of equipment, increased speed of electronic components, and more sophisticated software, radiation detection systems are now more productively used in many disciplines...

  9. Radiation detection device and a radiation detection method

    International Nuclear Information System (INIS)

    Blum, A.

    1975-01-01

    A radiation detection device is described including at least one scintillator in the path of radiation emissions from a distributed radiation source; a plurality of photodetectors for viewing each scintillator; a signal processing means, a storage means, and a data processing means that are interconnected with one another and connected to said photodetectors; and display means connected to the data processing means to locate a plurality of radiation sources in said distributed radiation source and to provide an image of the distributed radiation sources. The storage means includes radiation emission response data and location data from a plurality of known locations for use by the data processing means to derive a more accurate image by comparison of radiation responses from known locations with radiation responses from unknown locations. (auth)

  10. Measurement and detection of radiation

    CERN Document Server

    Tsoulfanidis, Nicholas

    2015-01-01

    This fourth edition reflects recent major developments that have occurred in radiation detector materials, systems, and applications. It continues to provide the most practical and up-to-date introduction to radiation detector technology, proper measurement techniques, and analysis of results for engineers and scientists using radiation sources. New chapters emphasize the expanded use of radiation detection systems in nuclear non-proliferation, homeland security, and nuclear medicine. The book also discusses the correct ways to perform measurements following current health physics procedures.

  11. Electronics for radiation detection

    CERN Document Server

    2011-01-01

    Addresses the developments in the design of semiconductor detectors and integrated circuits, in the context of medical imaging using ionizing radiation. This book explains how circuits for radiation are built, focusing on practical information about how they are being used, rather than mathematical details.

  12. Measurement and detection of radiation

    CERN Document Server

    Tsoulfanidis, Nicholas

    2011-01-01

    This is an update of the standard textbook for the field of radiation measurement. It includes illustrative examples and new problems. The research and applications of nuclear instrumentation have grown substantially since publication of the previous editions. With the miniaturization of equipment, increased speed of electronic components, and more sophisticated software, radiation detection systems are now more productively used in many disciplines, including nuclear nonproliferation, homeland security, and nuclear medicine. Continuing in the tradition of its bestselling predecessors, "Measurement and Detection of Radiation, Third Edition" illustrates the fundamentals of nuclear interactions and radiation detection with a multitude of examples and problems. It offers a clearly written, accessible introduction to nuclear instrumentation concepts. The following are new to the third edition: a new chapter on the latest applications of radiation detection, covering nuclear medicine, dosimetry, health physics, no...

  13. Radiation detection system

    Science.gov (United States)

    Whited, R.C.

    A system for obtaining improved resolution in relatively thick semiconductor radiation detectors, such as HgI/sub 2/, which exhibit significant hole trapping. Two amplifiers are used: the first measures the charge collected and the second the contribution of the electrons to the charge collected. The outputs of the two amplifiers are utilized to unfold the total charge generated within the detector in response to a radiation event.

  14. Aerial Radiation Detection

    International Nuclear Information System (INIS)

    Quam, W. M.

    1999-01-01

    An airborne system designed for the detection of radioactive sources on the soil surface from an aircraft normally senses gamma rays emitted by the source. Gamma rays have the longest path length (least attenuation) through the air of any of the common radioactive emissions and will thus permit source detection at large distances. A secondary benefit from gamma rays detection if that nearly all radioactive isotopes can be identified by the spectrum of gammas emitted. Major gaseous emissions from fuel processing plants emit gammas that may be detected and identified. Some types of special nuclear material also emit neutrons which are also useful for detection at a distance

  15. Detection of nuclear radiations

    International Nuclear Information System (INIS)

    Tanarro Sanz, A.

    1959-01-01

    A summary of the lectures about the ordinary detectors of nuclear radiations given by the author in the Courses of Introduction to Nuclear Engineering held at the JEN up to the date of publication is given. Those lectures are considered to be a necessary introduction to Nuclear Instrumentation and Applied electronics to Nuclear Engineering so it has been intent to underline those characteristics of radiation detectors that must be taken in consideration in choosing or designing the electronic equipment associated to them in order to take advantage of each detector possibilities. (Author) 8 refs

  16. Detection of nuclear radiations

    International Nuclear Information System (INIS)

    Tanarro Sanz, A.

    1967-01-01

    A summary of the lectures about the ordinary detectors of nuclear radiations explained by the author in the courses of Nuclear Engineering held at the J.E.N. up to the date of publication is given. Those lectures are considered to be a necessary introduction to Nuclear Instrumentation and Applied Electronics to Nuclear Engineering so it has been intended to underline those characteristics of radiation detectors that must be taken in consideration in choosing or designing the electronic equipment associated to them in order to take advantage of each detector possibilities. (Author)

  17. Detection of gravitational radiation

    Energy Technology Data Exchange (ETDEWEB)

    Holten, J.W. van [ed.

    1994-12-31

    In this report the main contributions presented at the named symposium are collected. These concern astrophysical sources of gravitational radiation, ultracryogenic gravitational wave experiments, read out and data analysis of gravitational wave antennas, cryogenic aspects of large mass cooling to mK temperatures, and metallurgical and engineering aspects of large Cu structure manufacturing. (HSI).

  18. Detection of gravitational radiation

    International Nuclear Information System (INIS)

    Holten, J.W. van

    1994-01-01

    In this report the main contributions presented at the named symposium are collected. These concern astrophysical sources of gravitational radiation, ultracryogenic gravitational wave experiments, read out and data analysis of gravitational wave antennas, cryogenic aspects of large mass cooling to mK temperatures, and metallurgical and engineering aspects of large Cu structure manufacturing. (HSI)

  19. Radiation detecting system

    International Nuclear Information System (INIS)

    1975-01-01

    In spectrophotometry systems, a usual arrangement for modulating the radiation is a rotating disc having one or more sectors removed. A beam of radiation may be blocked by the disc except when a cut-away sector is in the path of the beam. With a double-beam system, a cut-away sector of 180 0 may be used so that when the first path is blocked, the second is allowed through, and vice versa. One or both sides of the disc may be formed as mirrors to facilitate beam switching and to allow use of more than two beams for background compensation purposes or for analysis of more than one substance within a sample. (G.T.H.)

  20. Radiation detection systems

    International Nuclear Information System (INIS)

    Rozsa, Sandor

    1989-01-01

    Principles and operation of radiation detectors used for industrial and laboratory radiometric measurements are reviewed. The discussed detector types are as follows: ionization chamber, proportional counter, Geiger-Mueller counter, semiconductor detectors, scintillation counter and scintillators, photomultiplier tube, scintillation spectrometer and scintillation detector with semiconductor light sensor. A brief overview of the detectors of industrial nuclear instruments is also presented. (R.P.) 32 figs.; 3 tabs

  1. Radiation detection device

    International Nuclear Information System (INIS)

    Peschmann, Kristian.

    1982-01-01

    A radiation detector suitable for use in computer tomography device has an ionization chamber which comprises a high voltage electrode, a collector electrode, a high voltage source having two terminals, one connected to the high voltage electrode, current measuring means having two terminals, one connected to the high voltage source and the other to the collector electrode, and an auxilliary electrode near and parallel to the entrance window of the device, having one adjacent to the high voltage electrode and the other adjacent but not connected to the collector electrode. The auxilliary electrode is connected to the high voltage source. In this way the electric field between the high voltage and collector electrodes is made homogeneous in the vicinity of the auxilliary electrode, improving the measuring speed of the detector

  2. Radiation detection system

    Science.gov (United States)

    Riedel, Richard A [Knoxville, TN; Wintenberg, Alan L [Knoxville, TN; Clonts, Lloyd G [Knoxville, TN; Cooper, Ronald G [Oak Ridge, TN

    2012-02-14

    A preamplifier circuit for processing a signal provided by a radiation detector includes a transimpedance amplifier coupled to receive a current signal from a detector and generate a voltage signal at its output. A second amplification stage has an input coupled to an output of the transimpedance amplifier for providing an amplified voltage signal. Detector electronics include a preamplifier circuit having a first and second transimpedance amplifier coupled to receive a current signal from a first and second location on a detector, respectively, and generate a first and second voltage signal at respective outputs. A second amplification stage has an input coupled to an output of the transimpedance amplifiers for amplifying the first and said second voltage signals to provide first and second amplified voltage signals. A differential output stage is coupled to the second amplification stage for receiving the first and second amplified voltage signals and providing a pair of outputs from each of the first and second amplified voltage signals. Read out circuitry has an input coupled to receive both of the pair of outputs, the read out circuitry having structure for processing each of the pair of outputs, and providing a single digital output having a time-stamp therefrom.

  3. Origin, characteristics and detection of nuclear radiation

    International Nuclear Information System (INIS)

    Goettel, K.

    1975-06-01

    The report is an introduction into the physical principles of radiation protection. After a brief summary of the most significant experimental results and data on the atomic structure of the matter and after explaining the principles of atomic and nuclear structure, radioactive decay and its laws are dealt with. This is followed by a representation of the characteristics of nuclear radiation, its interaction with the matter as well as the biological effects. After a description of the measurement units for radioactivity and doses the most inportant methods for radiation detection and the principles of how detectors function are explained. (ORU/LN) [de

  4. Resonance detection of Moessbauer radiation

    International Nuclear Information System (INIS)

    Morozov, V.V.

    1985-01-01

    The resonance detection method as compared with the usual method of registering Moessbauer spectra has a number of advantages, one of which is the increase of resolution of the Moessbauer spectrum. The method is based on the modulation of a secondary radiation of a converter tuned in the resonance with the Moessbauer gamma-quantum source. The resonance detection method with account of supression, secondary radiation outgoing from the converter is investigated. The converter represents a substrate enriched by the Moessbauer isotope placed either inside the gas counter, or coupled with any other detecting device. Analytical expressions for Moessbauer spectrum parameters: effect, area and width of the spectral line are derived. It is shown that the joint application of usual and resonance detection methods for registering the Moessbauer spectrum allows one to determine parameters of the source, converter and the investigated absorber

  5. Analog electronics for radiation detection

    CERN Document Server

    2016-01-01

    Analog Electronics for Radiation Detection showcases the latest advances in readout electronics for particle, or radiation, detectors. Featuring chapters written by international experts in their respective fields, this authoritative text: Defines the main design parameters of front-end circuitry developed in microelectronics technologies Explains the basis for the use of complementary metal oxide semiconductor (CMOS) image sensors for the detection of charged particles and other non-consumer applications Delivers an in-depth review of analog-to-digital converters (ADCs), evaluating the pros and cons of ADCs integrated at the pixel, column, and per-chip levels Describes incremental sigma delta ADCs, time-to-digital converter (TDC) architectures, and digital pulse-processing techniques complementary to analog processing Examines the fundamental parameters and front-end types associated with silicon photomultipliers used for single visible-light photon detection Discusses pixel sensors ...

  6. Radiation Detection Computational Benchmark Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Shaver, Mark W.; Casella, Andrew M.; Wittman, Richard S.; McDonald, Ben S.

    2013-09-24

    Modeling forms an important component of radiation detection development, allowing for testing of new detector designs, evaluation of existing equipment against a wide variety of potential threat sources, and assessing operation performance of radiation detection systems. This can, however, result in large and complex scenarios which are time consuming to model. A variety of approaches to radiation transport modeling exist with complementary strengths and weaknesses for different problems. This variety of approaches, and the development of promising new tools (such as ORNL’s ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for

  7. Ionizing radiations, detection, dosimetry, spectrometry

    International Nuclear Information System (INIS)

    Blanc, D.

    1997-10-01

    A few works in French language are devoted to the detection of radiations. The purpose of this book is to fill a gap.The five first chapters are devoted to the properties of ionizing radiations (x rays, gamma rays, leptons, hadrons, nuclei) and to their interactions with matter. The way of classification of detectors is delicate and is studied in the chapter six. In the chapter seven are studied the statistics laws for counting and the spectrometry of particles is treated. The chapters eight to thirteen study the problems of ionization: charges transport in a gas, ionization chambers (theory of Boag), counters and proportional chambers, counters with 'streamers', chambers with derive, spark detectors, ionization chambers in liquid medium, Geiger-Mueller counters. The use of a luminous signal is the object of the chapters 14 to 16: conversion of a luminous signal in an electric signal, scintillators, use of the Cerenkov radiation. Then, we find the neutron detection with the chapter seventeen and the dosimetry of particles in the chapter eighteen. This book does not pretend to answer to specialists questions but can be useful to physicians, engineers or physics teachers. (N.C.)

  8. Cellular telephone-based radiation detection instrument

    Science.gov (United States)

    Craig, William W [Pittsburg, CA; Labov, Simon E [Berkeley, CA

    2011-06-14

    A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

  9. Plasmonically enhanced thermomechanical detection of infrared radiation.

    Science.gov (United States)

    Yi, Fei; Zhu, Hai; Reed, Jason C; Cubukcu, Ertugrul

    2013-04-10

    Nanoplasmonics has been an attractive area of research due to its ability to localize and manipulate freely propagating radiation on the nanometer scale for strong light-matter interactions. Meanwhile, nanomechanics has set records in the sensing of mass, force, and displacement. In this work, we report efficient coupling between infrared radiation and nanomechanical resonators through nanoantenna enhanced thermoplasmonic effects. Using efficient conversion of electromagnetic energy to mechanical energy in this plasmo-thermomechanical platform with a nanoslot plasmonic absorber integrated directly on a nanobeam mechanical resonator, we demonstrate room-temperature detection of nanowatt level power fluctuations in infrared radiation. We expect our approach, which combines nanoplasmonics with nanomechanical resonators, to lead to optically controlled nanomechanical systems enabling unprecedented functionality in biomolecular and toxic gas sensing and on-chip mass spectroscopy.

  10. Physics and engineering of radiation detection

    CERN Document Server

    Ahmed, Syed Naeem

    2015-01-01

    Physics and Engineering of Radiation Detection presents an overview of the physics of radiation detection and its applications. It covers the origins and properties of different kinds of ionizing radiation, their detection and measurement, and the procedures used to protect people and the environment from their potentially harmful effects. The second edition is fully revised and provides the latest developments in detector technology and analyses software. Also, more material related to measurements in particle physics and a complete solutions manual have been added.

  11. Bubble Radiation Detection: Current and Future Capability

    International Nuclear Information System (INIS)

    Peurrung, A.J.; Craig, R.A.

    1999-01-01

    Despite a number of noteworthy achievements in other fields, superheated droplet detectors (SDDs) and bubble chambers (BCs) have not been used for nuclear nonproliferation and arms control. This report examines these two radiation-detection technologies in detail and answers the question of how they can be or should be ''adapted'' for use in national security applications. These technologies involve closely related approaches to radiation detection in which an energetic charged particle deposits sufficient energy to initiate the process of bubble nucleation in a superheated fluid. These detectors offer complete gamma-ray insensitivity when used to detect neutrons. They also provide controllable neutron-energy thresholds and excellent position resolution. SDDs are extraordinarily simple and inexpensive. BCs offer the promise of very high efficiency (∼75%). A notable drawback for both technologies is temperature sensitivity. As a result of this problem, the temperature must be controlled whenever high accuracy is required, or harsh environmental conditions are encountered. The primary findings of this work are listed and briefly summarized below: (1) SDDs are ready to function as electronics-free neutron detectors on demand for arms-control applications. The elimination of electronics at the weapon's location greatly eases the negotiability of radiation-detection technologies in general. (2) As a result of their high efficiency and sharp energy threshold, current BCs are almost ready for use in the development of a next-generation active assay system. Development of an instrument based on appropriately safe materials is warranted. (3) Both kinds of bubble detectors are ready for use whenever very high gamma-ray fields must be confronted. Spent fuel MPC and A is a good example where this need presents itself. (4) Both kinds of bubble detectors have the potential to function as low-cost replacements for conventional neutron detectors such as 3 He tubes. For SDDs

  12. Detecting radiation with your smartphone

    CERN Multimedia

    Agnes Szeberenyi

    2014-01-01

    The winners of the CERN EIROforum Prize in the European Union Competition for Young Scientists 2013 (EUCYS), Michał Gumiela and Rafał Tomasz Kozik from Poland, have just spent an exciting week exploring CERN from 1 to 5 September. The students visited several CERN experiments and facilities and had ample time to interact with scientists on how to improve their invention further.   Michał Gumiela (left) and Rafał Tomasz Kozik (right) with their CERN host, Sabrina El Yacoubi (middle) at the ALICE detector. Michał (21) and Rafał (20) both won a young physicist prize in Poland before submitting their work on “Studies of the applicability of CMOS and CCD sensors for detection of ionising radiation” to the EUCYS competition. “It all started with Fukushima,” recalls Michał. The high school students met in 2011 at a physics workshop, where they started discussing digital photos taken around the Fukushima nuclear plant after the radiation leak. &ldqu...

  13. Split energy level radiation detection

    International Nuclear Information System (INIS)

    Barnes, G.T.

    1986-01-01

    This patent describes an energy discriminating radiation detector comprising: (a) a first element comprising a first material of a kind which is preferentially responsive to penetrative radiation of a first energy range; (b) a second element comprising a second material different in kind from the first material and of a kind which is preferentially responsive to penetrative radiation of second energy range extending higher than the first energy range. The element is positioned to receive radiation which has penetrated through a portion of the first element; and (c) a filter of penetrative radiation interposed between the first and second elements

  14. Study of the casting speedy radiation-detection system

    International Nuclear Information System (INIS)

    Tan Xiaochun; Huang Junqing; Shi Xianbei; Zhao Gang; Wang Liping

    2001-01-01

    The paper introduces the design of the launching speedy radiation-detection system. It consists of launcher, semiconductor detector, microprocessor and communicator. It can give the intensity, position, time of radiation. The paper discusses the function, composition, principle, speciality and technical problem of this system

  15. Radiation Detection Center on the Front Lines

    International Nuclear Information System (INIS)

    Hazi, A

    2005-01-01

    Many of today's radiation detection tools were developed in the 1960s. For years, the Laboratory's expertise in radiation detection resided mostly within its nuclear test program. When nuclear testing was halted in the 1990s, many of Livermore's radiation detection experts were dispersed to other parts of the Laboratory, including the directorates of Chemistry and Materials Science (CMS); Physics and Advanced Technologies (PAT); Defense and Nuclear Technologies (DNT); and Nonproliferation, Arms Control, and International Security (NAI). The RDC-- was formed to maximize the benefit of radiation detection technologies being developed in 15 to 20 research and development (R and D) programs. These efforts involve more than 200 Laboratory employees across eight directorates, in areas that range from electronics to computer simulations. The RDC's primary focus is the detection, identification, and analysis of nuclear materials and weapons. A newly formed outreach program within the RDC-- is responsible for conducting radiation detection workshops and seminars across the country and for coordinating university student internships. Simon Labov, director of the RDC, says, ''Virtually all of the Laboratory's programs use radiation detection devices in some way. For example, DNT uses radiation detection to create radiographs for their work in stockpile stewardship and in diagnosing explosives; CMS uses it to develop technology for advancing the detection, diagnosis, and treatment of cancer; and the Energy and Environment Directorate uses radiation detection in the Marshall Islands to monitor the aftermath of nuclear testing in the Pacific. In the future, the National Ignition Facility will use radiation detection to probe laser targets and study shock dynamics.''

  16. Bayesian Methods for Radiation Detection and Dosimetry

    CERN Document Server

    Groer, Peter G

    2002-01-01

    We performed work in three areas: radiation detection, external and internal radiation dosimetry. In radiation detection we developed Bayesian techniques to estimate the net activity of high and low activity radioactive samples. These techniques have the advantage that the remaining uncertainty about the net activity is described by probability densities. Graphs of the densities show the uncertainty in pictorial form. Figure 1 below demonstrates this point. We applied stochastic processes for a method to obtain Bayesian estimates of 222Rn-daughter products from observed counting rates. In external radiation dosimetry we studied and developed Bayesian methods to estimate radiation doses to an individual with radiation induced chromosome aberrations. We analyzed chromosome aberrations after exposure to gammas and neutrons and developed a method for dose-estimation after criticality accidents. The research in internal radiation dosimetry focused on parameter estimation for compartmental models from observed comp...

  17. Graphene Field Effect Transistor for Radiation Detection

    Science.gov (United States)

    Li, Mary J. (Inventor); Chen, Zhihong (Inventor)

    2016-01-01

    The present invention relates to a graphene field effect transistor-based radiation sensor for use in a variety of radiation detection applications, including manned spaceflight missions. The sensing mechanism of the radiation sensor is based on the high sensitivity of graphene in the local change of electric field that can result from the interaction of ionizing radiation with a gated undoped silicon absorber serving as the supporting substrate in the graphene field effect transistor. The radiation sensor has low power and high sensitivity, a flexible structure, and a wide temperature range, and can be used in a variety of applications, particularly in space missions for human exploration.

  18. Radiation, ionization, and detection in nuclear medicine

    International Nuclear Information System (INIS)

    Gupta, Tapan K.

    2013-01-01

    Up-to-date information on a wide range of topics relating to radiation, ionization, and detection in nuclear medicine. In-depth coverage of basic radiophysics relating to diagnosis and therapy. Extensive discussion of instrumentation and radiation detectors. Detailed information on mathematical modelling of radiation detectors. Although our understanding of cancer has improved, the disease continues to be a leading cause of death across the world. The good news is that the recent technological developments in radiotherapy, radionuclide diagnostics and therapy, digital imaging systems, and detection technology have raised hope that cancer will in the future be combatted more efficiently and effectively. For this goal to be achieved, however, safe use of radionuclides and detailed knowledge of radiation sources are essential. Radiation, Ionization, and Detection in Nuclear Medicine addresses these subjects and related issues very clearly and elaborately and will serve as the definitive source of detailed information in the field. Individual chapters cover fundamental aspects of nuclear radiation, including dose and energy, sources, and shielding; the detection and measurement of radiation exposure, with detailed information on mathematical modelling; medical imaging; the different types of radiation detector and their working principles; basic principles of and experimental techniques for deposition of scintillating materials; device fabrication; the optical and electrical behaviors of radiation detectors; and the instrumentation used in nuclear medicine and its application. The book will be an invaluable source of information for academia, industry, practitioners, and researchers.

  19. Radiation, ionization, and detection in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Tapan K. [Radiation Monitoring Devices Research, Nuclear Medicine, Watertown, MA (United States)

    2013-08-01

    Up-to-date information on a wide range of topics relating to radiation, ionization, and detection in nuclear medicine. In-depth coverage of basic radiophysics relating to diagnosis and therapy. Extensive discussion of instrumentation and radiation detectors. Detailed information on mathematical modelling of radiation detectors. Although our understanding of cancer has improved, the disease continues to be a leading cause of death across the world. The good news is that the recent technological developments in radiotherapy, radionuclide diagnostics and therapy, digital imaging systems, and detection technology have raised hope that cancer will in the future be combatted more efficiently and effectively. For this goal to be achieved, however, safe use of radionuclides and detailed knowledge of radiation sources are essential. Radiation, Ionization, and Detection in Nuclear Medicine addresses these subjects and related issues very clearly and elaborately and will serve as the definitive source of detailed information in the field. Individual chapters cover fundamental aspects of nuclear radiation, including dose and energy, sources, and shielding; the detection and measurement of radiation exposure, with detailed information on mathematical modelling; medical imaging; the different types of radiation detector and their working principles; basic principles of and experimental techniques for deposition of scintillating materials; device fabrication; the optical and electrical behaviors of radiation detectors; and the instrumentation used in nuclear medicine and its application. The book will be an invaluable source of information for academia, industry, practitioners, and researchers.

  20. Principles of nuclear radiation detection

    International Nuclear Information System (INIS)

    Eichholz, G.G.; Poston, J.W.

    1985-01-01

    This book covers the transistorization of equipment and provides an introduction into practice of semiconductor and thermoluminescent detectors. It discusses the principles of radiation detectors most widely used in nuclear technology, medical practice and radiation protection. It stresses the alternative detectors available and discusses practical considerations in choosing and setting up detector systems for actual use. Traditional materials, including semiconductors, TLD's and modern data handling facilities are covered

  1. Indirect detection of radiation sources through direct detection of radiolysis products

    Science.gov (United States)

    Farmer, Joseph C [Tracy, CA; Fischer, Larry E [Los Gatos, CA; Felter, Thomas E [Livermore, CA

    2010-04-20

    A system for indirectly detecting a radiation source by directly detecting radiolytic products. The radiation source emits radiation and the radiation produces the radiolytic products. A fluid is positioned to receive the radiation from the radiation source. When the fluid is irradiated, radiolytic products are produced. By directly detecting the radiolytic products, the radiation source is detected.

  2. Physics and engineering of radiation detection

    CERN Document Server

    Ahmed, Syed Naeem

    2007-01-01

    Physics and Engineering of Radiation Detection presents an overview of basic physics of radiation and its applications and covers the origins and properties of different kinds of ionizing radiation, their detection and measurement, and the procedures used to protect people and the environment from their potentially harmful effects. Covering both the basic physics of radiation and its applications, it will provide an up-to-date and coherent account of the origins and properties of the different kinds of ionizing radiation, and their detection and measurement. This book will illustrate the basic physical principles with an abundance of practical, worked-out examples, numerical problems, real world applications, and data, including biological effects, radon, risk assessment, and statistics.

  3. Blackbody radiation functions and polylogarithms

    International Nuclear Information System (INIS)

    Stewart, Seán M.

    2012-01-01

    A new method based on the polylogarithm function is used to derive an exact expression for the fractional emissive power of a blackbody in any arbitrary spectral band. Compared to all previously used methods the polylogarithm based method is unsurpassed in its simplicity. Displacement laws for the centroid of blackbody radiation in the linear wavelength and frequency spectral representations that make use of the polylogarithm based approach are also given.

  4. Pulse X-radiation in flaw detection

    International Nuclear Information System (INIS)

    Vavilov, S.P.; Gorbunov, V.I.

    1985-01-01

    Principles of physical and engineering application of pulse X-radiation (PXR) of micro- and nanosecond duration for nondestructive testing of processes, materials and devices are given. Methods and devices, aimed at generating X-ray pulses, as well as their radiation and flow detection characteristics, and testing methods by means of PXR are considered

  5. Device for detecting ionizing radiation

    International Nuclear Information System (INIS)

    Anatychuk, L.I.; Kharitonov, J.P.; Kusniruk, V.F.; Meir, V.A.; Melnik, A.P.; Ponomarev, V.S.; Skakodub, V.A.; Sokolov, A.D.; Subbotin, V.G.; Zhukovsky, A.N.

    1980-01-01

    The present invention relates to ionizing radiation sensors, and , more particularly, to semiconductor spectrometers with thermoelectric cooling, and can most advantageously be used in mineral raw material exploration and evaluation under field conditions. The spectrometer comprises a vacuum chamber with an entrance window for passing the radiation therethrough. The vacuum chamber accommodates a thermoelectric cooler formed by a set of peltier elements. A heat conducting plate is mounted on the cold side of the thermoelectric cooler, and its hot side is provided with a radiator. Mounted on the heat conducting plate are sets of peltier elements, integral with the thermoelectric cooler and independent of one another. The peltier elements of these sets are stacked so as to develop the minimum temperature conditions on one set carrying a semiconductor detector and to provide the maximum refrigeration capacity conditions on the other set provided with the field-effect transistor mounted thereon

  6. Assembly for detecting penetrating radiation

    International Nuclear Information System (INIS)

    Froggatt, R.J.

    1978-01-01

    The detector to pick up the X-rays emitted from a cross-sectional plane of a patient (computer tomography) consists of a cadmium sulfide monocrystal, an ultrasonic transmitter, and an ultrasonic receiver. The X-rays hit the crystal at right angle to a d.c. drift field applied on the electrons generated by the X-radiation. The ultrasonic field may strike the crystal parallel or at some angle with respect to this d.c. drift field. The energefically changed sound wave picked up by the ultrasonic receiver respectively its amplitude is a measure for the intensity of the X-radiation. (DG) [de

  7. Radiation Detection for Homeland Security Applications

    Science.gov (United States)

    Ely, James

    2008-05-01

    In the past twenty years or so, there have been significant changes in the strategy and applications for homeland security. Recently there have been significant at deterring and interdicting terrorists and associated organizations. This is a shift in the normal paradigm of deterrence and surveillance of a nation and the `conventional' methods of warfare to the `unconventional' means that terrorist organizations resort to. With that shift comes the responsibility to monitor international borders for weapons of mass destruction, including radiological weapons. As a result, countries around the world are deploying radiation detection instrumentation to interdict the illegal shipment of radioactive material crossing international borders. These efforts include deployments at land, rail, air, and sea ports of entry in the US and in European and Asian countries. Radioactive signatures of concern include radiation dispersal devices (RDD), nuclear warheads, and special nuclear material (SNM). Radiation portal monitors (RPMs) are used as the main screening tool for vehicles and cargo at borders, supplemented by handheld detectors, personal radiation detectors, and x-ray imaging systems. This talk will present an overview of radiation detection equipment with emphasis on radiation portal monitors. In the US, the deployment of radiation detection equipment is being coordinated by the Domestic Nuclear Detection Office within the Department of Homeland Security, and a brief summary of the program will be covered. Challenges with current generation systems will be discussed as well as areas of investigation and opportunities for improvements. The next generation of radiation portal monitors is being produced under the Advanced Spectroscopic Portal program and will be available for deployment in the near future. Additional technologies, from commercially available to experimental, that provide additional information for radiation screening, such as density imaging equipment, will

  8. Silicon solid state devices and radiation detection

    CERN Document Server

    Leroy, Claude

    2012-01-01

    This book addresses the fundamental principles of interaction between radiation and matter, the principles of working and the operation of particle detectors based on silicon solid state devices. It covers a broad scope with respect to the fields of application of radiation detectors based on silicon solid state devices from low to high energy physics experiments including in outer space and in the medical environment. This book covers stateof- the-art detection techniques in the use of radiation detectors based on silicon solid state devices and their readout electronics, including the latest developments on pixelated silicon radiation detector and their application.

  9. Labor security in radiation flaw detection

    International Nuclear Information System (INIS)

    Margulis, U.Ya.; Chistov, E.D.; Partolin, O.F.; Pertsov, V.A.; Momzhiev, B.N.; Sprygaev, I.F.

    1986-01-01

    Problems of ensuring safe labour conditions in radiation flaw detection are considered. Methods for ionizing radiation protection are given calculating techniques for shielding flaw detectors and stationary structures are presented as well. Safe methods of nondestructive testing of items under field conditions, in a shop and special laboratories using gamma- and X-ray flaw detectors, betatrons, electron accelerators are described. Attention is paid to the principles of radiation factor stantardization as well as radiation monitoring. Analysis of accidents and recommendations on their prevention and liquidation of accidental consequences are given

  10. Detection and measurement of ionizing radiation

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    All detection or measurement of radiation rests in the possibility of recognizing the interactions of radiation with matter. When radiation passes through any kind of material medium, all or a portion of its energy is transferred to this medium. This transferred energy produces an effect in the medium. In principle, the detection of radiation is based on the appearance and the observation of this effect. In theory, all of the effects produced by radiation may be used in detecting it: in practice, the effects most commonly employed are: (1) ionization of gases (gas detectors), or of some chemical substance which is transformed by radiation (photographic or chemical dosimeters); (2) excitations in scintillators or semiconductors (scintillation counters, semiconductor counters); (3) creation of structural defects through the passage of radiation (transparent thermoluminescent and radioluminescent detectors); and (4) raising of the temperature (calorimeters). This study evaluates in detail, instruments based on the ionization of gases and the production of luminescence. In addition, the authors summarize instruments which depend on other forms of interaction, used in radiation medicine and hygiene (radiology, nuclear medicine)

  11. Electrets for beta radiation detection

    International Nuclear Information System (INIS)

    Campos, L.L.; Caldas, L.V.E.; Mascarenhas, S.

    1983-01-01

    Electret dosimetry has been reviewed by Gross. A cylindrical electret ionization-chamber type dosimeter has been studied for X and gamma rays and neutrons. The principle of the dosimeter is electret charge compensation due to ionization in the chamber volume. Electret ionization chambers can be designed with one or more electrets and in various shapes. This study is concerned with a simple system, similar to a cylindrical ionization chamber (sensitive volume: 3,5 cm 3 ) using teflon electrets. Aluminum and lucite were used as wall-materials. Other experiences were performed using chambers without wall, i.e., without defined sensitive volume. The teflon electrets were obtained by Corona discharge in the gas surrounding them. The measurement of the electret charge was made by induction using a co-axial insulated metal chamber connected to an electrometer Keithley 610C. By measuring the charge before and after irradiation it is possible to obtain a calibration curve: charge (Q) versus absorbed dose (D) for the dosimeter. The irradiation setup used was the Beta Secondary Standard System of IPEN calibration laboratory with four beta sources: 90 Sr 90 Y (74 and 1850 MBq), 204 Tl (18,5 MBq) and 147 Pm (518 MBq). In some cases a 85 Kr source was also used. The electrets were tested in different radiation field geometries: electret axis parallel and perpendicular to the field. In conclusion, depending on the wall material and radiation field geometry, the teflon electret detector can be used for different dose interval determinations, using beta radiation

  12. Adaptive search and detection of laser radiation

    International Nuclear Information System (INIS)

    Efendiev, F.A.; Kasimova, F.I.

    2008-01-01

    Formation of cosmic optical line connected with the solving of difficult problems, among which stand out spatial search task, detection and target tracking. Indeed, the main advantage of systems of the optical diapason, high radiation direction leads to a challenging task of entering in communication, consisting in mutual targeting antenna receiving and transmitting systems. Algorithm detection, obtained by solving the corresponding statistical optimal detection test synthesis tasks detector determines the structure and quality of his work which depend on the average characteristics of the signal and the background radiation of the thermal noise require full priori certainty about the conditions of observation. Algorithm of the optimal detector of laser light modulated on a sub carrier frequency of intensity assumes a priori known intensity and efficiency background radiation and internal noise power photo detector

  13. Optical fiber-applied radiation detection system

    International Nuclear Information System (INIS)

    Nishiura, Ryuichi; Uranaka, Yasuo; Izumi, Nobuyuki

    2001-01-01

    A technique to measure radiation by using plastic scintillation fibers doped radiation fluorescent (scintillator) to plastic optical fiber for a radiation sensor, was developed. The technique contains some superiority such as high flexibility due to using fibers, relatively easy large area due to detecting portion of whole of fibers, and no electromagnetic noise effect due to optical radiation detection and signal transmission. Measurable to wide range of and continuous radiation distribution along optical fiber cable at a testing portion using scintillation fiber and flight time method, the optical fiber-applied radiation sensing system can effectively monitor space radiation dose or apparatus operation condition monitoring. And, a portable type scintillation optical fiber body surface pollution monitor can measure pollution concentration of radioactive materials attached onto body surface by arranging scintillation fiber processed to a plate with small size and flexibility around a man to be tested. Here were described on outline and fundamental properties of various application products using these plastic scintillation fiber. (G.K.)

  14. Bayesian Methods for Radiation Detection and Dosimetry

    International Nuclear Information System (INIS)

    Peter G. Groer

    2002-01-01

    We performed work in three areas: radiation detection, external and internal radiation dosimetry. In radiation detection we developed Bayesian techniques to estimate the net activity of high and low activity radioactive samples. These techniques have the advantage that the remaining uncertainty about the net activity is described by probability densities. Graphs of the densities show the uncertainty in pictorial form. Figure 1 below demonstrates this point. We applied stochastic processes for a method to obtain Bayesian estimates of 222Rn-daughter products from observed counting rates. In external radiation dosimetry we studied and developed Bayesian methods to estimate radiation doses to an individual with radiation induced chromosome aberrations. We analyzed chromosome aberrations after exposure to gammas and neutrons and developed a method for dose-estimation after criticality accidents. The research in internal radiation dosimetry focused on parameter estimation for compartmental models from observed compartmental activities. From the estimated probability densities of the model parameters we were able to derive the densities for compartmental activities for a two compartment catenary model at different times. We also calculated the average activities and their standard deviation for a simple two compartment model

  15. Detection of food treated with ionizing radiation

    International Nuclear Information System (INIS)

    Delincee, H.

    1998-01-01

    Treatment of food with ionizing energy-'food irradiation'- is finally becoming reality in many countries. The benefits include an improvement in food hygiene, spoilage reduction and extension of shelf-life. Although properly irradiated food is safe and wholesome, consumers should be able to make their own free choice between irradiated and non-irradiated food. For this purpose labelling is indispensable. In order to check compliance with existing regulations, detection of radiation treatment by analysing the food itself is highly desirable. Significant progress has been made in recent years in developing analytical detection methods utilizing changes in food originating from the radiation treatment

  16. Remote Optical Detection of Alpha Radiation

    International Nuclear Information System (INIS)

    Sand, J.; Hannuksela, V.; Toivonen, J.; Ihantola, S.; Peraejaervi, K.; Toivonen, H.

    2010-01-01

    Alpha emitting radiation sources are typically hard to detect with conventional detectors due to the short range of alpha particles in the air. However, previous studies have shown that remote detection of alpha radiation is possible by measuring the ionization-induced fluorescence of air molecules. The alpha-induced ultraviolet (UV) light is mainly emitted by molecular nitrogen and its fluorescence properties are well known. The benefit of this method is the long range of UV photons in the air. Secondly, the detection is possible also under a strong beta and gamma radiation backgrounds as they do not cause localized molecular excitation. In this work, the optical detection was studied using two different detection schemes; spectral separation of fluorescence from the background lighting and coincidence detection of UV photons originating from a single radiative decay event. Our spectrally integrated measurements have shown that one alpha decay event yields up to 400 fluorescence photons in the air and all these UV photons are induced in a 5 ns time-window. On the other hand, the probability of a background coincidence event in 5 ns scale is very rare compared to the number of background photons. This information can be applied in fluorescence coincidence filtering to discriminate the alpha radiation initiated fluorescence signal from much more intense background lighting. A device called HAUVA (Handheld Alpha UV Application) was built during this work for demonstration purposes. HAUVA utilizes spectral filtering and it is designed to detect alpha emitters from a distance of about 40 cm. Using specially selected room lighting, the device is able to separate 1 kBq alpha emitter from the background lighting with 1 second integration time. (author)

  17. Precision of quantum tomographic detection of radiation

    Energy Technology Data Exchange (ETDEWEB)

    D' Ariano, G.M. (Dipartimento di Fisica ' ' Alessandro Volta' ' , Via A. Bassi 6, I-27100, Pavia (Italy) Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, Via A. Bassi 6, I-27100, Pavia (Italy)); Macchiavello, Chiara (Dipartimento di Fisica ' ' Alessandro Volta' ' , Via A. Bassi 6, I-27100, Pavia (Italy)); Paris, M.G.A. (Dipartimento di Fisica ' ' Alessandro Volta' ' , Via A. Bassi 6, I-27100, Pavia (Italy))

    1994-11-21

    Homodyne tomography provides an experimental technique for reconstructing the density matrix of the radiation field. Here we analyze the tomographic precision in recovering observables like the photon number, the quadrature, and the phase. We show that tomographic reconstruction, despite providing a complete characterization of the state of the field, is generally much less efficient than conventional detection techniques. ((orig.))

  18. Precision of quantum tomographic detection of radiation

    International Nuclear Information System (INIS)

    D'Ariano, G.M.; Macchiavello, Chiara; Paris, M.G.A.

    1994-01-01

    Homodyne tomography provides an experimental technique for reconstructing the density matrix of the radiation field. Here we analyze the tomographic precision in recovering observables like the photon number, the quadrature, and the phase. We show that tomographic reconstruction, despite providing a complete characterization of the state of the field, is generally much less efficient than conventional detection techniques. ((orig.))

  19. Nuclear Forensics and Radiochemistry: Radiation Detection

    Energy Technology Data Exchange (ETDEWEB)

    Rundberg, Robert S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-08

    Radiation detection is necessary for isotope identification and assay in nuclear forensic applications. The principles of operation of gas proportional counters, scintillation counters, germanium and silicon semiconductor counters will be presented. Methods for calibration and potential pitfalls in isotope quantification will be described.

  20. Nuclear Forensics and Radiochemistry: Radiation Detection

    International Nuclear Information System (INIS)

    Rundberg, Robert S.

    2017-01-01

    Radiation detection is necessary for isotope identification and assay in nuclear forensic applications. The principles of operation of gas proportional counters, scintillation counters, germanium and silicon semiconductor counters will be presented. Methods for calibration and potential pitfalls in isotope quantification will be described.

  1. Composite scintillators for detection of ionizing radiation

    Science.gov (United States)

    Dai, Sheng [Knoxville, TN; Stephan, Andrew Curtis [Knoxville, TN; Brown, Suree S [Knoxville, TN; Wallace, Steven A [Knoxville, TN; Rondinone, Adam J [Knoxville, TN

    2010-12-28

    Applicant's present invention is a composite scintillator having enhanced transparency for detecting ionizing radiation comprising a material having optical transparency wherein said material comprises nano-sized objects having a size in at least one dimension that is less than the wavelength of light emitted by the composite scintillator wherein the composite scintillator is designed to have selected properties suitable for a particular application.

  2. Detection of electromagnetic radiation using nonlinear materials

    Science.gov (United States)

    Hwang, Harold Y.; Liu, Mengkun; Averitt, Richard D.; Nelson, Keith A.; Sternbach, Aaron; Fan, Kebin

    2016-06-14

    An apparatus for detecting electromagnetic radiation within a target frequency range is provided. The apparatus includes a substrate and one or more resonator structures disposed on the substrate. The substrate can be a dielectric or semiconductor material. Each of the one or more resonator structures has at least one dimension that is less than the wavelength of target electromagnetic radiation within the target frequency range, and each of the resonator structures includes at least two conductive structures separated by a spacing. Charge carriers are induced in the substrate near the spacing when the resonator structures are exposed to the target electromagnetic radiation. A measure of the change in conductivity of the substrate due to the induced charge carriers provides an indication of the presence of the target electromagnetic radiation.

  3. Development of Quantum Devices and Algorithms for Radiation Detection and Radiation Signal Processing

    International Nuclear Information System (INIS)

    El Tokhy, M.E.S.M.E.S.

    2012-01-01

    The main functions of spectroscopy system are signal detection, filtering and amplification, pileup detection and recovery, dead time correction, amplitude analysis and energy spectrum analysis. Safeguards isotopic measurements require the best spectrometer systems with excellent resolution, stability, efficiency and throughput. However, the resolution and throughput, which depend mainly on the detector, amplifier and the analog-to-digital converter (ADC), can still be improved. These modules have been in continuous development and improvement. For this reason we are interested with both the development of quantum detectors and efficient algorithms of the digital processing measurement. Therefore, the main objective of this thesis is concentrated on both 1. Study quantum dot (QD) devices behaviors under gamma radiation 2. Development of efficient algorithms for handling problems of gamma-ray spectroscopy For gamma radiation detection, a detailed study of nanotechnology QD sources and infrared photodetectors (QDIP) for gamma radiation detection is introduced. There are two different types of quantum scintillator detectors, which dominate the area of ionizing radiation measurements. These detectors are QD scintillator detectors and QDIP scintillator detectors. By comparison with traditional systems, quantum systems have less mass, require less volume, and consume less power. These factors are increasing the need for efficient detector for gamma-ray applications such as gamma-ray spectroscopy. Consequently, the nanocomposite materials based on semiconductor quantum dots has potential for radiation detection via scintillation was demonstrated in the literature. Therefore, this thesis presents a theoretical analysis for the characteristics of QD sources and infrared photodetectors (QDIPs). A model of QD sources under incident gamma radiation detection is developed. A novel methodology is introduced to characterize the effect of gamma radiation on QD devices. The rate

  4. Radiation sensitive area detection device and method

    Science.gov (United States)

    Carter, Daniel C. (Inventor); Hecht, Diana L. (Inventor); Witherow, William K. (Inventor)

    1991-01-01

    A radiation sensitive area detection device for use in conjunction with an X ray, ultraviolet or other radiation source is provided which comprises a phosphor containing film which releases a stored diffraction pattern image in response to incoming light or other electromagnetic wave. A light source such as a helium-neon laser, an optical fiber capable of directing light from the laser source onto the phosphor film and also capable of channelling the fluoresced light from the phosphor film to an integrating sphere which directs the light to a signal processing means including a light receiving means such as a photomultiplier tube. The signal processing means allows translation of the fluoresced light in order to detect the original pattern caused by the diffraction of the radiation by the original sample. The optical fiber is retained directly in front of the phosphor screen by a thin metal holder which moves up and down across the phosphor screen and which features a replaceable pinhole which allows easy adjustment of the resolution of the light projected onto the phosphor film. The device produces near real time images with high spatial resolution and without the distortion that accompanies prior art devices employing photomultiplier tubes. A method is also provided for carrying out radiation area detection using the device of the invention.

  5. Measuring element for the detection and determination of radiation doses of gamma radiation and neutrons

    International Nuclear Information System (INIS)

    Jahn, W.; Piesch, E.

    1975-01-01

    A measuring element detects and proves both gamma and neutron radiation. The element includes a photoluminescent material which stores gamma radiation and particles of arsenic and phosphorus embedded in the photoluminescent material for detecting neutron radiation. (U.S.)

  6. Waveshifters and Scintillators for Ionizing Radiation Detection

    International Nuclear Information System (INIS)

    Baumgaugh, B.; Bishop, J.; Karmgard, D.; Marchant, J.; McKenna, M.; Ruchti, R.; Vigneault, M.; Hernandez, L.; Hurlbut, C.

    2007-01-01

    Scintillation and waveshifter materials have been developed for the detection of ionizing radiation in an STTR program between Ludlum Measurements, Inc. and the University of Notre Dame. Several new waveshifter materials have been developed which are comparable in efficiency and faster in fluorescence decay than the standard material Y11 (K27) used in particle physics for several decades. Additionally, new scintillation materials useful for fiber tracking have been developed which have been compared to 3HF. Lastly, work was done on developing liquid scintillators and paint-on scintillators and waveshifters for high radiation environments

  7. Optical fiber applied to radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Junior, Francisco A.B.; Costa, Antonella L.; Oliveira, Arno H. de; Vasconcelos, Danilo C., E-mail: fanbra@yahoo.com.br, E-mail: antonella@nuclear.ufmg.br, E-mail: heeren@nuclear.ufmg.br, E-mail: danilochagas@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Escola de Engenharia. Departamento de Engenharia Nuclear

    2015-07-01

    In the last years, the production of optical fibers cables has make possible the development of a range of spectroscopic probes for in situ analysis performing beyond nondestructive tests, environmental monitoring, security investigation, application in radiotherapy for dose monitoring, verification and validation. In this work, a system using an optical fiber cable to light signal transmission from a NaI(Tl) radiation detector is presented. The innovative device takes advantage mainly of the optical fibers small signal attenuation and immunity to electromagnetic interference to application for radiation detection systems. The main aim was to simplify the detection system making it to reach areas where the conventional device cannot access due to its lack of mobility and external dimensions. Some tests with this innovative system are presented and the results stimulate the continuity of the researches. (author)

  8. Detection of radiation processing in onions

    International Nuclear Information System (INIS)

    Duchacek, V.

    1985-01-01

    Two breeds of onions were used for irradiation. Both breeds were divided into two parts - the first was irradiated with a dose of 80 Gy and the second served as a control. The two parts were stored under the same conditions. Conductometry, liquid chromatography and spectrophotometry were used for detecting the radiation processing of the onions. Only from the spectrophotometric determination of 2-desoxysaccharides it was possible to safely distinguish irradiated onions from non-irradiated controls throughout storage time. (E.S.)

  9. Nuclear radiation detection by a variband semiconductor

    International Nuclear Information System (INIS)

    Volkov, A.S.

    1981-01-01

    Possibilities of using a variband semiconductor for detecting nuclear radiations are considered. It is shown that the variaband quasielectric field effectively collects charges induced by a nuclear particle only at a small mean free path in the semiconductor (up to 100 μm), the luminescence spectrum of the variband semiconductor when a nuclear particle gets into it, in principle, permits to determine both the energy and mean free path in the semiconductor (even at large mean free paths) [ru

  10. Multichannel Digital Emulator of Radiation Detection Systems

    International Nuclear Information System (INIS)

    Abba, A.; Caponio, F.; Geraci, A.

    2013-06-01

    A digital system for emulating in real time signals from generic setups for radiation detection is presented. The instrument is not a pulse generator of recorded shapes but a synthesizer of random pulses compliant to programmable statistics for energy and occurrence time. Completely programmable procedures for emulation of noise, disturbances and reference level variation can be implemented. The instrument has been realized and fully tested. (authors)

  11. Radiation detection technology assessment program (RADTAP)

    International Nuclear Information System (INIS)

    Smith, D.E.

    1998-01-01

    The U.S. Customs Service and the U.S. Department of Energy (DOE) conducted a technical and operational assessment of gamma ray radiation detection equipment during the period May 5-16, 1997 at a testing facility in North Carolina. The effort was entitled, ''Radiation Detection Technology Assessment Program (RADTAP)'', and was conducted for the purpose of assessing the applicability, sensitivity and robustness of a diverse suite of gamma ray detection and identification equipment for possible use by Customs and other law enforcement agencies. Thirteen companies entered 25 instruments into the assessment program. All detection equipment entered had to exhibit a minimum sensitivity of 20 micro-R per hour (background included) from a Cesium-137 point source. Isotope identifying spectrometers entered were man portable and operable at room temperature with read-out that could be interpreted by non-technical personnel. Radioactive sources used in the assessment included special nuclear material, industrial and health isotopes. Evaluators included Customs inspectors and technical experts from DOE and Customs. No conclusions or recommendations were issued based on the quantitative and qualitative test results, however, the results of the program provided law enforcement agencies with the necessary data to select equipment that best meets their operational needs and budgets. (author)

  12. Networked gamma radiation detection system for tactical deployment

    Science.gov (United States)

    Mukhopadhyay, Sanjoy; Maurer, Richard; Wolff, Ronald; Smith, Ethan; Guss, Paul; Mitchell, Stephen

    2015-08-01

    A networked gamma radiation detection system with directional sensitivity and energy spectral data acquisition capability is being developed by the National Security Technologies, LLC, Remote Sensing Laboratory to support the close and intense tactical engagement of law enforcement who carry out counterterrorism missions. In the proposed design, three clusters of 2″ × 4″ × 16″ sodium iodide crystals (4 each) with digiBASE-E (for list mode data collection) would be placed on the passenger side of a minivan. To enhance localization and facilitate rapid identification of isotopes, advanced smart real-time localization and radioisotope identification algorithms like WAVRAD (wavelet-assisted variance reduction for anomaly detection) and NSCRAD (nuisance-rejection spectral comparison ratio anomaly detection) will be incorporated. We will test a collection of algorithms and analysis that centers on the problem of radiation detection with a distributed sensor network. We will study the basic characteristics of a radiation sensor network and focus on the trade-offs between false positive alarm rates, true positive alarm rates, and time to detect multiple radiation sources in a large area. Empirical and simulation analyses of critical system parameters, such as number of sensors, sensor placement, and sensor response functions, will be examined. This networked system will provide an integrated radiation detection architecture and framework with (i) a large nationally recognized search database equivalent that would help generate a common operational picture in a major radiological crisis; (ii) a robust reach back connectivity for search data to be evaluated by home teams; and, finally, (iii) a possibility of integrating search data from multi-agency responders.

  13. Cellular telephone-based wide-area radiation detection network

    Science.gov (United States)

    Craig, William W [Pittsburg, CA; Labov, Simon E [Berkeley, CA

    2009-06-09

    A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

  14. Application of single-chip microcomputer in radiation detection

    International Nuclear Information System (INIS)

    Zhang Songshou

    1993-01-01

    The single-chip microcomputer has some advantages in many aspects for example the strong function, the small volume, the low-power, firmed and reliable. It is used widely in the control of industry, instrument, communication and machine, etc.. The paper introduces that the single-chip microcomputer is used in radiation detection, mostly including the use of control, linear, compensation, calculation, prefabricated change, improving precision and training

  15. Detecting solar chameleons through radiation pressure

    CERN Document Server

    Baum, Sebastian

    2014-01-01

    Light scalar fields can drive accelerated expansion of the universe. Hence, scalars are obvious dark energy candidates. To make these models compatible with test of General Relativity in the solar system and fifth force searches on earth, one needs to screen them. One possibility is the chameleon mechanism, which renders an effective mass depending on the local energy density. If chameleons exist, they can be produced in the sun and detected on earth through their radiation pressure. We calculate the solar chameleon spectrum and the sensitivity of an experiment to be carried out at CAST, CERN, utilizing a radiation pressure sensor currently under development at INFN, Trieste. We show that such an experiment will be sensitive to a wide range of model parameters and signifies a pioneering effort searching for chameleons in unprobed paramterspace.

  16. Pencil-shaped radiation detection ionization chamber

    International Nuclear Information System (INIS)

    Suzuki, A.

    1979-01-01

    A radiation detection ionization chamber is described. It consists of an elongated cylindrical pencil-shaped tubing forming an outer wall of the chamber and a center electrode disposed along the major axis of the tubing. The length of the chamber is substantially greater than the diameter. A cable connecting portion at one end of the chamber is provided for connecting the chamber to a triaxial cable. An end support portion is connected at the other end of the chamber for supporting and tensioning the center electrode. 17 claims

  17. Detecting solar chameleons through radiation pressure

    CERN Document Server

    Baum, S.; Hoffmann, D.H.H.; Karuza, M.; Semertzidis, Y.K.; Upadhye, A.; Zioutas, K.

    2014-10-24

    Light scalar fields can drive the accelerated expansion of the universe. Hence, they are obvious dark energy candidates. To make such models compatible with tests of General Relativity in the solar system and "fifth force" searches on Earth, one needs to screen them. One possibility is the so-called "chameleon" mechanism, which renders an effective mass depending on the local matter density. If chameleon particles exist, they can be produced in the sun and detected on earth exploiting the equivalent of a radiation pressure. Since their effective mass scales with the local matter density, chameleons can be reflected by a dense medium if their effective mass becomes greater than their total energy. Thus, under appropriate conditions, a flux of solar chameleons may be sensed by detecting the total instantaneous momentum transferred to a suitable opto-mechanical force/pressure sensor. We calculate the solar chameleon spectrum and the reach in the chameleon parameter space of an experiment using the preliminary re...

  18. Passive radiation detection using optically active CMOS sensors

    Science.gov (United States)

    Dosiek, Luke; Schalk, Patrick D.

    2013-05-01

    Recently, there have been a number of small-scale and hobbyist successes in employing commodity CMOS-based camera sensors for radiation detection. For example, several smartphone applications initially developed for use in areas near the Fukushima nuclear disaster are capable of detecting radiation using a cell phone camera, provided opaque tape is placed over the lens. In all current useful implementations, it is required that the sensor not be exposed to visible light. We seek to build a system that does not have this restriction. While building such a system would require sophisticated signal processing, it would nevertheless provide great benefits. In addition to fulfilling their primary function of image capture, cameras would also be able to detect unknown radiation sources even when the danger is considered to be low or non-existent. By experimentally profiling the image artifacts generated by gamma ray and β particle impacts, algorithms are developed to identify the unique features of radiation exposure, while discarding optical interaction and thermal noise effects. Preliminary results focus on achieving this goal in a laboratory setting, without regard to integration time or computational complexity. However, future work will seek to address these additional issues.

  19. Thyorid function after mantle field radiation therapy

    International Nuclear Information System (INIS)

    Daehnert, W.; Kutzner, J.; Grimm, W.

    1981-01-01

    48 patients with malignant lymphoma received a 60 Co-radiation dose of 30 to 50 Gy using the mantle field technique. Thyroid function tests were performed 34 to 92 months after radiation therapy. One patient developed myxedema, ten (20.8%) had subclinical hypothyroidism and six (12.5%) latent hypothyroidism. The incidence of hypothyroidism after treatment of malignant lymphomas is summarized in a review of the literature. Discrepancies on the incidence of hypothyroidism were found, and their possible cause is discussed. Periodic examinations of all patients with thyroid radiation exposure are recommended. The examination can be limited to measurement of TSH concentration and palpation of the thyroid for nodules. (orig.) [de

  20. Radiation detection and measurement concepts, methods and devices

    CERN Document Server

    McGregor, Douglas

    2019-01-01

    This text on radiation detection and measurement is a response to numerous requests expressed by students at various universities, in which the most popularly used books do not provide adequate background material, nor explain matters in understandable terms. This work provides a modern overview of radiation detection devices and radiation measurement methods. The topics selected in the book have been selected on the basis of the author’s many years of experience designing radiation detectors and teaching radiation detection and measurement in a classroom environment.

  1. Synthesis of functional materials by radiation

    International Nuclear Information System (INIS)

    Nho, Young Chang; Kim, Ki Yup; Kang, Phil Hyun and others

    2000-04-01

    The radiation can induce chemical reaction to modify polymer under even the solid condition or in the low temperature. Therefore, the radiation processing is used as the means to develop the high functional polymer and new material which is impossible by chemical process. The radiation grafting process has the advantage to endow the adsorption function to the existing materials such as polymer membrane, fabric, non-fabric, non-woven fabric and film. Radiation crosslinking is effected with no pressure and is performed at low temperatures. Thus, temperature sensitive additives can be used in radiation crosslinking. The radiation crosslinking and grafting can be easily adjusted and is easily reproducible by controlling the radiation dose. The finished product contains no residuals of substances required to initiate the chemical crosslinking and grafting which can restrict the application possibilities, or can increase the failure rate. In these studies, radiation grafting and crosslinking were used to develop the toxic gas adsorbent, blood compatible polymer, acetabular cup of artificial joint, urokinase adsorbent, hydrogel, hollow fiber membrane adsorbing the heavy metals, and battery separator membrane. Because cable in nuclear power plant is directly related to safe operation, the life assessment of the cable system is an important issue. To assess the degradation and life time of cable is complicated owing to the various types and the different formulation of cable. In order to make an estimate the long term degradation occurring in a material, it is necessary to carry out the accelerated aging studies and to establish the appropriate test method to characterize the degradation. These studies are aimed at the evaluation technique on radiation degradation of polymer material and applying these results to nuclear equipment qualification

  2. Synthesis of functional materials by radiation

    Energy Technology Data Exchange (ETDEWEB)

    Nho, Young Chang; Kim, Ki Yup; Kang, Phil Hyun and others

    2000-04-01

    The radiation can induce chemical reaction to modify polymer under even the solid condition or in the low temperature. Therefore, the radiation processing is used as the means to develop the high functional polymer and new material which is impossible by chemical process. The radiation grafting process has the advantage to endow the adsorption function to the existing materials such as polymer membrane, fabric, non-fabric, non-woven fabric and film. Radiation crosslinking is effected with no pressure and is performed at low temperatures. Thus, temperature sensitive additives can be used in radiation crosslinking. The radiation crosslinking and grafting can be easily adjusted and is easily reproducible by controlling the radiation dose. The finished product contains no residuals of substances required to initiate the chemical crosslinking and grafting which can restrict the application possibilities, or can increase the failure rate. In these studies, radiation grafting and crosslinking were used to develop the toxic gas adsorbent, blood compatible polymer, acetabular cup of artificial joint, urokinase adsorbent, hydrogel, hollow fiber membrane adsorbing the heavy metals, and battery separator membrane. Because cable in nuclear power plant is directly related to safe operation, the life assessment of the cable system is an important issue. To assess the degradation and life time of cable is complicated owing to the various types and the different formulation of cable. In order to make an estimate the long term degradation occurring in a material, it is necessary to carry out the accelerated aging studies and to establish the appropriate test method to characterize the degradation. These studies are aimed at the evaluation technique on radiation degradation of polymer material and applying these results to nuclear equipment qualification.

  3. Radiation detection technique on the fishery foods

    International Nuclear Information System (INIS)

    Oikawa, Hiroshi; Satomi, Masataka; Nakamura, Koji; Yano, Yutaka

    1999-01-01

    Recently irradiation of fishery products such as sea bream, lobster etc has been spreading in South-east Asia. It is thus necessary to establish a detection technique for irradiated foods . This study aimed to investigate the effects of irradiation on the production of tyrosine isomers with relation to the status of food sample (frozen and cold-storage) and also the stabilities of the isomers in frozen foods after irradiation. Production of tyrosin isomers (meta-tyrosine, ortho-tyrosine) due to γ-ray irradiation (5 kGy) were observed in the muscles of frozen prawns as well as those at room temperature and the contents of these isomers after the irradiation was not different between the two states of the sample. The content increased depending on the radiation dose. The contents of these tyrosine isomers were not changed after storage at -20degC for 120 days. Therefore, it was thought that the tyrosine isomers were available as an effective indicator for detection of an irradiated food. (M.N.)

  4. Detecting solar chameleons through radiation pressure

    International Nuclear Information System (INIS)

    Baum, S.; Cantatore, G.; Hoffmann, D.H.H.; Karuza, M.; Semertzidis, Y.K.; Upadhye, A.; Zioutas, K.

    2014-01-01

    Light scalar fields can drive the accelerated expansion of the universe. Hence, they are obvious dark energy candidates. To make such models compatible with tests of General Relativity in the solar system and “fifth force” searches on Earth, one needs to screen them. One possibility is the so-called “chameleon” mechanism, which renders an effective mass depending on the local matter density. If chameleon particles exist, they can be produced in the sun and detected on Earth exploiting the equivalent of a radiation pressure. Since their effective mass scales with the local matter density, chameleons can be reflected by a dense medium if their effective mass becomes greater than their total energy. Thus, under appropriate conditions, a flux of solar chameleons may be sensed by detecting the total instantaneous momentum transferred to a suitable opto-mechanical force/pressure sensor. We calculate the solar chameleon spectrum and the reach in the chameleon parameter space of an experiment using the preliminary results from a force/pressure sensor, currently under development at INFN Trieste, to be mounted in the focal plane of one of the X-Ray telescopes of the CAST experiment at CERN. We show, that such an experiment signifies a pioneering effort probing uncharted chameleon parameter space

  5. Detecting solar chameleons through radiation pressure

    Energy Technology Data Exchange (ETDEWEB)

    Baum, S., E-mail: sebastian.baum@cern.ch [Uppsala Universitet, Box 516, SE 75120, Uppsala (Sweden); European Organization for Nuclear Research (CERN), Gèneve (Switzerland); Cantatore, G. [Università di Trieste, Via Valerio 2, 34127 Trieste (Italy); INFN Trieste, Padriciano 99, 34149 Trieste (Italy); Hoffmann, D.H.H. [Institut für Kernphysik, TU-Darmstadt, Schlossgartenstr. 9, D-64289 Darmstadt (Germany); Karuza, M. [INFN Trieste, Padriciano 99, 34149 Trieste (Italy); Phys. Dept. and CMNST, University of Rijeka, R. Matejcic 2, Rijeka (Croatia); Semertzidis, Y.K. [Center for Axion and Precision Physics Research (IBS), Daejeon 305-701 (Korea, Republic of); Department of Physics, KAIST, Daejeon 305-701 (Korea, Republic of); Upadhye, A. [Physics Department, University of Wisconsin–Madison, 1150 University Avenue, Madison, WI 53706 (United States); Zioutas, K., E-mail: konstantin.zioutas@cern.ch [European Organization for Nuclear Research (CERN), Gèneve (Switzerland); University of Patras, GR 26504 Patras (Greece)

    2014-12-12

    Light scalar fields can drive the accelerated expansion of the universe. Hence, they are obvious dark energy candidates. To make such models compatible with tests of General Relativity in the solar system and “fifth force” searches on Earth, one needs to screen them. One possibility is the so-called “chameleon” mechanism, which renders an effective mass depending on the local matter density. If chameleon particles exist, they can be produced in the sun and detected on Earth exploiting the equivalent of a radiation pressure. Since their effective mass scales with the local matter density, chameleons can be reflected by a dense medium if their effective mass becomes greater than their total energy. Thus, under appropriate conditions, a flux of solar chameleons may be sensed by detecting the total instantaneous momentum transferred to a suitable opto-mechanical force/pressure sensor. We calculate the solar chameleon spectrum and the reach in the chameleon parameter space of an experiment using the preliminary results from a force/pressure sensor, currently under development at INFN Trieste, to be mounted in the focal plane of one of the X-Ray telescopes of the CAST experiment at CERN. We show, that such an experiment signifies a pioneering effort probing uncharted chameleon parameter space.

  6. Radiation detection and diagnosis of breast cancer

    International Nuclear Information System (INIS)

    Dodd, G.D.

    1981-01-01

    The value of mammography in the symptomatic patient has been adequately documented, but its use as a detection procedure remains a question. Risk-benefit ratios, based primarily upon the study carried out by the Health Insurance Plan of Greater New York, have suggested that the technique has little value in individuals under age 50. Emphasis has been placed upon the possible carcinogenic effects of radiation as compared with the efficacy of mammography and the questionable influence of early diagnosis upon end results. Although technical advances have substantially reduced the exposure of the patient to radiation, the possibility of significant information loss as the result of these developments has been considered a potential drawback to their routine use. All of these factors have served to diminish both public and professional acceptance of the examination. Although current data do not allow complete resolution of these problems, certain conclusions may be drawn and trends established. The sum of these may indicate that minimal dose mammography is an accurate, low-risk procedure, capable of significantly altering the natural history of breast cancer. Whether or not the examination should be routinely used in women under age 50 remains open to question since the lack of experimental controls prohibits validation of the technique in terms of reduced mortality rates. Documentation of increased survival rates may partially assist in the established of a reliable risk-benefit ratio, but will not satisfy the statistical requirements of eliminating lead-bias, and self-selection. These questions may be resolved by studies now underway

  7. Neutron and/or gamma radiation detecting system

    International Nuclear Information System (INIS)

    Cerff, K.

    1985-01-01

    A large reception surface for the radiation to be detected is formed on a body of scintillation material (ZnS-AG with B matrix) which is adapted to convert neutron or gamma radiation into light energy. A large number of fiber light conductors is embedded in the body of scintillation material such that the fibers extend essentially parallel and fully across the reception surface of the body of scintillation material. The light energy, upon propagation along the fiber light conductors, is coupled into the conductors along the surface of the fibers which are unisotropic. This arrangement permits the use of unisotropic light conductor systems which provide for a separation of light collecting and light transmitting functions which results in a substantial reduction of light absorption losses during light transmission so that most of the light energy coupled into the fiber light conductors reaches the optoelectronic amplifier coupled to the end of the light conductors. (orig./HP) [de

  8. Undoped poly (phenyl sulfone) for radiation detection

    International Nuclear Information System (INIS)

    Nakamura, Hidehito; Shirakawa, Yoshiyuki; Sato, Nobuhiro; Kitamura, Hisashi; Takahashi, Sentaro

    2015-01-01

    Undoped aromatic ring polymers are potential scintillation materials. Here, we characterise poly (phenyl sulfone) (PPSU) for radiation detection. The amber-coloured transparent resin emits bluish-white fluorescence with 390-nm maximum. It has an excitation maximum of 340 nm, and has a density of 1.29 g/cm 3 . The effective refractive index based on its emission spectrum is 1.75. The light yield is almost equal to that of poly (ethylene terephthalate), which is a transparent resin. These results demonstrate that PPSU can be used as a component substrate in polymer blends for altering optical characteristics. - Highlights: • Poly (phenyl sulfone) (PPSU) has suitable characteristics as a scintillation material. • PPSU is an amber-coloured transparent resin that emits bluish white fluorescence with 390-nm maximum. • The 1.75 effective refractive index over the emission spectrum is relatively high. • The light yield is 0.95 times that of poly (ethylene terephthalate), which is a transparent resin. • PPSU can potentially alter optical characteristics in polymer blends

  9. Recent developments in analytical detection methods for radiation processed foods

    International Nuclear Information System (INIS)

    Wu Jilan

    1993-01-01

    A short summary of the programmes of 'ADMIT' (FAO/IAEA) and the developments in analytical detection methods for radiation processed foods has been given. It is suggested that for promoting the commercialization of radiation processed foods and controlling its quality, one must pay more attention to the study of analytical detection methods of irradiated food

  10. Compiler-Agnostic Function Detection in Binaries

    NARCIS (Netherlands)

    Andriesse, D.A.; Slowinska, J.M.; Bos, H.J.

    2017-01-01

    We propose Nucleus, a novel function detection algorithm for binaries. In contrast to prior work, Nucleus is compiler-agnostic, and does not require any learning phase or signature information. Instead of scanning for signatures, Nucleus detects functions at the Control Flow Graph-level, making it

  11. Radiations - induced disorders in ovarian function

    International Nuclear Information System (INIS)

    Saleh, S.; Roushdy, H.M.; Abdel-Aziz, M.T.; Eldenshary, A.E.; Abdel-Khalek, A.; Ramadan, L.A.

    1988-01-01

    The effect of whole body gamma radiation exposure (7.5 and 6.5 Gy) on the secretory activity and the structure of the ovaries was investigated. The parameters studied were serum levels of oestrogen, progesterone, Lh and FSH, beside histopathological studies of the ovaries of femaler rats. These were measured on the next day after radiation exposure and then after one two oestrus cycles. Whole body gamma - irradiation of females rats at two levels of exposure progressively decreased the level of oestrogen and progesterone while increased the level of LH and FSH as compared with the control. moreover, the changes in the ovaries were demonstrated in the histopathological investigation. Keywords: Radiation exposure - ovarian function - hormone radioimmunoassay - oestrogen - progesterone - LH - FSH

  12. Three-dimensional, position-sensitive radiation detection

    Science.gov (United States)

    He, Zhong; Zhang, Feng

    2010-04-06

    Disclosed herein is a method of determining a characteristic of radiation detected by a radiation detector via a multiple-pixel event having a plurality of radiation interactions. The method includes determining a cathode-to-anode signal ratio for a selected interaction of the plurality of radiation interactions based on electron drift time data for the selected interaction, and determining the radiation characteristic for the multiple-pixel event based on both the cathode-to-anode signal ratio and the electron drift time data. In some embodiments, the method further includes determining a correction factor for the radiation characteristic based on an interaction depth of the plurality of radiation interactions, a lateral distance between the selected interaction and a further interaction of the plurality of radiation interactions, and the lateral positioning of the plurality of radiation interactions.

  13. Paraxial Green's functions in synchrotron radiation theory

    International Nuclear Information System (INIS)

    Geloni, G.; Saldin, E.; Scheidmiller, E.; Yurkov, M.

    2005-02-01

    This work contains a systematic treatment of single particle synchrotron radiation and some application to realistic beams with given cross section area, divergence and energy spread. Standard theory relies on several approximations whose applicability limits and accuracy are often forgotten. We begin remarking that on the one hand, a paraxial approximation can always be applied without loss of generality and with ultra relativistic accuracy. On the other hand, dominance of the acceleration field over the velocity part in the Lienard-Wiechert expressions is not always guaranteed and constitutes a separate assumption, whose applicability is discussed. Treating synchrotron radiation in paraxial approximation we derive the equation for the slow varying envelope function of the Fourier components of the electric field vector. Calculations of Synchrotron Radiation properties performed by others showed that the phase of the Fourier components of the electric field vector differs from the phase of a virtual point source. In this paper we present a systematic, analytical description of this phase shift, calculating amplitude and phase of electric field from bending magnets, short magnets, two bending magnet system separated by a straight section (edge radiation) and undulator devices. We pay particular attention to region of applicability and accuracy of approximations used. Finally, taking advantage of results of analytical calculation presented in reduced form we analyze various features of radiation from a complex insertion device (set of two undulators with a focusing triplet in between) accounting for the influence of energy spread and electron beam emittance. (orig.)

  14. On the γ-photon detection processes and the statistics of radiation

    International Nuclear Information System (INIS)

    Bertolotti, M.; Sibilia, C.

    1977-01-01

    The problem of detection of γ-photons is treated in the cases of photoelectric and Compton effects. In both cases the probability of detecting a γ-photon is found proportional to the first-order correlation function of the e.m. field. The statistical properties of the γ-radiation can therefore be determined through the methods developed in quantum optics

  15. Radiation damage prediction system using damage function

    International Nuclear Information System (INIS)

    Tanaka, Yoshihisa; Mori, Seiji

    1979-01-01

    The irradiation damage analysis system using a damage function was investigated. This irradiation damage analysis system consists of the following three processes, the unfolding of a damage function, the calculation of the neutron flux spectrum of the object of damage analysis and the estimation of irradiation effect of the object of damage analysis. The damage function is calculated by applying the SAND-2 code. The ANISN and DOT3, 5 codes are used to calculate neutron flux. The neutron radiation and the allowable time of reactor operation can be estimated based on these calculations of the damage function and neutron flux. The flow diagram of the process of analyzing irradiation damage by a damage function and the flow diagram of SAND-2 code are presented, and the analytical code for estimating damage, which is determined with a damage function and a neutron spectrum, is explained. The application of the irradiation damage analysis system using a damage function was carried out to the core support structure of a fast breeder reactor for the damage estimation and the uncertainty evaluation. The fundamental analytical conditions and the analytical model for this work are presented, then the irradiation data for SUS304, the initial estimated values of a damage function, the error analysis for a damage function and the analytical results are explained concerning the computation of a damage function for 10% total elongation. Concerning the damage estimation of FBR core support structure, the standard and lower limiting values of damage, the permissible neutron flux and the allowable years of reactor operation are presented and were evaluated. (Nakai, Y.)

  16. Radiation Detection Overview for Nuclear Emergency Response

    Energy Technology Data Exchange (ETDEWEB)

    Myers, Steven Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-16

    This presentation discusses the fundamentals of gamma and neutron detection; presents an overview of the DOE Triage and JTOT Programs, gamma, and neutron signatures in select measurements; and offers a detector demonstration.

  17. Nuclear radiation detection with superconducting tunnel junctions

    International Nuclear Information System (INIS)

    Kurakado, Masahiko

    1984-01-01

    Since the gap energy of superconductors is as small as 1 meV and 1/1000 of that of semiconductors, it is expected that the number of electron-hole pairs produced in superconductors by radiation is several thousands times as many as the pairs in semiconductors. Therefore, high sensitivity and high resolution radiation detectors may be manufactured by using superconductors. A computer simulation of the cascade excitation process of electrons was carried out. The experimental study was performed by using Sn junctions. The variation of transient voltage was measured by the constant current method. The alpha particles from Po-210 were measured, and the generation of quasi particles was confirmed. The relaxation time of signals was measured by using pulsed laser beam. It was found that the superconductors just after the incidence of radiation became nonequilibrium. The typical alpha spectra were obtained by cooling the superconductors to 0.32 K. The detector is still under development. The problem is leakage current. (Kato, T.)

  18. Effects of radiation on parotid salivary function

    International Nuclear Information System (INIS)

    Marks, J.E.; Davis, C.C.; Gottsman, V.L.

    1981-01-01

    Postoperative electron beam irradiation of patients with parotid cancer has been used regularly at the Mallinckrodt Institute of Radiology to spare the opposite parotid and to preserve salivary function. Only anecdotal reports of amount of radiation required to ablate salivary function exist. To establish a dose-response curve for the human parotid, selective measurements of right and left parotid salivary flow were done for 15 age-matched control patients whose parotids were not irradiated, 17 patients who had both parotids irradiated, and 12 whose parotids were irradiated by unilateral electron beam technique. Point calculations of absorbed dose 1 cm below the surface were done for all 88 parotids and correlated with stimulated parotid salivary flow, pH, and secretory IgA (SIgA). Increasing doses of radiation resulted in progressive reduction of parotid salivary flow, pH, and SIgA. The technique, dosimetry, and clinical application of unilateral electron beam irradiation to spare the opposite parotid will be discussed

  19. Rubella virus detection by ELISA method in exposed radiation workers

    International Nuclear Information System (INIS)

    Wu Jianmei; Zhu Bo; Zhu Youming; Shao Jinhui; Wu Weiping; Han Jinxiang

    2005-01-01

    Objective: A rapid diagnosis method was developed to detect Rubella virus infection in radiation workers. Methods: Modified ELISA method was used to detect the level of lgG and lgM antibodies in 514 in Jinan district. Results: 90.47% of 514 cases was shown to be resistant against Rubella virus; 6.42% were sensitive type; 0.78% belonged to be reinfected. Conclusion: Detection of Rubella virus in exposed radiation workers was imperative, and vaccine against Rubella virus was also needed to eliminate the infection risk. (authors)

  20. Advanced concepts in multi-dimensional radiation detection and imaging

    International Nuclear Information System (INIS)

    Vetter, Kai; Barnowski, Ross; Pavlovsky, Ryan; Haefner, Andy; Torii, Tatsuo; Shikaze, Yoshiaki; Sanada, Yukihisa

    2016-01-01

    Recent developments in the detector fabrication, signal readout, and data processing enable new concepts in radiation detection that are relevant for applications ranging from fundamental physics to medicine as well as nuclear security and safety. We present recent progress in multi-dimensional radiation detection and imaging in the Berkeley Applied Nuclear Physics program. It is based on the ability to reconstruct scenes in three dimensions and fuse it with gamma-ray image information. We are using the High-Efficiency Multimode Imager HEMI in its Compton imaging mode and combining it with contextual sensors such as the Microsoft Kinect or visual cameras. This new concept of volumetric imaging or scene data fusion provides unprecedented capabilities in radiation detection and imaging relevant for the detection and mapping of radiological and nuclear materials. This concept brings us one step closer to the seeing the world with gamma-ray eyes. (author)

  1. The EPR detection of radiation treated foodstuffs

    International Nuclear Information System (INIS)

    Stachowicz, W.; Burlinska, G.; Michalik, J.; Ostrowski, K.; Dziedzic-Goclawska, A.

    1993-01-01

    The short paper by a Polish study group describes the results of the use of Electron Paramagnetic Resonance (EPR) Spectroscopy in the detection of irradiation to food. Pultry, fresh-water fish and sea fish as well as various fruits and yellow boletus are dealt with in some detail. (VHE) [de

  2. Screening for early detection of radiation-associated thyroid cancer

    International Nuclear Information System (INIS)

    Ron, E.; Modan, B.; Lubin, E.

    1984-01-01

    In the 1950s, approximately 20,000 Israeli children received scalp irradiation as treatment for tinea capitis (ringworm of the scalp). To evaluate the necessity and feasibility of early screening of these individuals for thyroid cancer, a small pilot program was undertaken. The examination consisted of a thorough palpation of the thyroid gland and the surrounding area. A sup(99m)Tc thyroid scan and thyroid function tests were performed on individuals in whom palpation suggested a nodular abnormality. A multidisciplinary committee then made a recommendation for or against surgery. A total of 443 persons were screened, and nodular abnormalities of the thyroid were detected in 24 (5.4%). Of these persons, nine displayed symptomatology or reported knowledge of a thyroid condition; despite this, three of them were not receiving treatment. This left 18 subjects - 15 new cases and 3 previously untreated patients - needing follow-up care. Altogether nine persons were recommended for surgery, but one refused. All eight of the excised lesions were benign: four colloid nodules and four adenomas. While the screening program was feasible, the fact that no cancers were detected suggested that in a population exposed to a very low dose of radiation, thyroid screening may not be justified on a large scale.

  3. Development of radiation detection and measurement systems

    Energy Technology Data Exchange (ETDEWEB)

    Moon, B. S.; Ham, C. S.; Chung, C. E. and others

    2000-03-01

    This report contains descriptions on the following six items. The first item is the result of a study on CsI(TI) crystals with their light emitting characteristics and the result of a study on plastic scintillators. The second item is the result of a study on advanced radiation detectors and includes experiments for the effect of using a Compton suppressor with an HPGe detector. For the third item, we describe the results of a design work done using EGS4 for a thickness gauge, a density gauge, and a level gauge. The fourth item contains descriptions on the prototype circuit systems developed for a level gauge, a thickness gauge, and for a survey meter. The fifth part contains the computed tomography algorithm and a prototype scanning system developed for a CT system. As the sixth and the last item, we describe the prototype high precision heat source and the prototype heat-voltage converter which we have designed and fabricated.

  4. Development of radiation detection and measurement systems

    International Nuclear Information System (INIS)

    Moon, B. S.; Ham, C. S.; Chung, C. E. and others

    2000-03-01

    This report contains descriptions on the following six items. The first item is the result of a study on CsI(TI) crystals with their light emitting characteristics and the result of a study on plastic scintillators. The second item is the result of a study on advanced radiation detectors and includes experiments for the effect of using a Compton suppressor with an HPGe detector. For the third item, we describe the results of a design work done using EGS4 for a thickness gauge, a density gauge, and a level gauge. The fourth item contains descriptions on the prototype circuit systems developed for a level gauge, a thickness gauge, and for a survey meter. The fifth part contains the computed tomography algorithm and a prototype scanning system developed for a CT system. As the sixth and the last item, we describe the prototype high precision heat source and the prototype heat-voltage converter which we have designed and fabricated

  5. Optimised mounting conditions for poly (ether sulfone) in radiation detection.

    Science.gov (United States)

    Nakamura, Hidehito; Shirakawa, Yoshiyuki; Sato, Nobuhiro; Yamada, Tatsuya; Kitamura, Hisashi; Takahashi, Sentaro

    2014-09-01

    Poly (ether sulfone) (PES) is a candidate for use as a scintillation material in radiation detection. Its characteristics, such as its emission spectrum and its effective refractive index (based on the emission spectrum), directly affect the propagation of light generated to external photodetectors. It is also important to examine the presence of background radiation sources in manufactured PES. Here, we optimise the optical coupling and surface treatment of the PES, and characterise its background. Optical grease was used to enhance the optical coupling between the PES and the photodetector; absorption by the grease of short-wavelength light emitted from PES was negligible. Diffuse reflection induced by surface roughening increased the light yield for PES, despite the high effective refractive index. Background radiation derived from the PES sample and its impurities was negligible above the ambient, natural level. Overall, these results serve to optimise the mounting conditions for PES in radiation detection. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Low Dose Ionizing Radiation Modulates Immune Function

    International Nuclear Information System (INIS)

    Nelson, Gregory A.

    2016-01-01

    In order to examine the effects of low dose ionizing radiation on the immune system we chose to examine an amplified adaptive cellular immunity response. This response is Type IV delayed-type hypersensitivity also called contact hypersensitivity. The agent fluorescein isothiocyanate (FITC) is a low molecular weight, lipophilic, reactive, fluorescent molecule that can be applied to the skin where it (hapten) reacts with proteins (carriers) to become a complete antigen. Exposure to FITC leads to sensitization which is easily measured as a hypersensitivity inflammatory reaction following a subsequent exposure to the ear. Ear swelling, eosinophil infiltration, immunoglobulin E production and cytokine secretion patterns characteristic of a 'Th2 polarized' immune response are the components of the reaction. The reaction requires successful implementation of antigen processing and presentation by antigen presenting Langerhans cells, communication with naïve T lymphocytes in draining lymph nodes, expansion of activated T cell clones, migration of activated T cells to the circulation, and recruitment of memory T cells, macrophages and eosinophils to the site of the secondary challenge. Using this model our approach was to quantify system function rather than relying only on indirect biomarkers of cell. We measured the FITC-induced hypersensitivity reaction over a range of doses from 2 cGy to 2 Gy. Irradiations were performed during key events or prior to key events to deplete critical cell populations. In addition to quantifying the final inflammatory response, we assessed cell populations in peripheral blood and spleen, cytokine signatures, IgE levels and expression of genes associated with key processes in sensitization and elicitation/recall. We hypothesized that ionizing radiation would produce a biphasic effect on immune system function resulting in an enhancement at low doses and a depression at higher doses and suggested that this transition would occur in

  7. Low Dose Ionizing Radiation Modulates Immune Function

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Gregory A. [Loma Linda Univ., CA (United States)

    2016-01-12

    In order to examine the effects of low dose ionizing radiation on the immune system we chose to examine an amplified adaptive cellular immunity response. This response is Type IV delayed-type hypersensitivity also called contact hypersensitivity. The agent fluorescein isothiocyanate (FITC) is a low molecular weight, lipophilic, reactive, fluorescent molecule that can be applied to the skin where it (hapten) reacts with proteins (carriers) to become a complete antigen. Exposure to FITC leads to sensitization which is easily measured as a hypersensitivity inflammatory reaction following a subsequent exposure to the ear. Ear swelling, eosinophil infiltration, immunoglobulin E production and cytokine secretion patterns characteristic of a “Th2 polarized” immune response are the components of the reaction. The reaction requires successful implementation of antigen processing and presentation by antigen presenting Langerhans cells, communication with naïve T lymphocytes in draining lymph nodes, expansion of activated T cell clones, migration of activated T cells to the circulation, and recruitment of memory T cells, macrophages and eosinophils to the site of the secondary challenge. Using this model our approach was to quantify system function rather than relying only on indirect biomarkers of cell. We measured the FITC-induced hypersensitivity reaction over a range of doses from 2 cGy to 2 Gy. Irradiations were performed during key events or prior to key events to deplete critical cell populations. In addition to quantifying the final inflammatory response, we assessed cell populations in peripheral blood and spleen, cytokine signatures, IgE levels and expression of genes associated with key processes in sensitization and elicitation/recall. We hypothesized that ionizing radiation would produce a biphasic effect on immune system function resulting in an enhancement at low doses and a depression at higher doses and suggested that this transition would occur in the

  8. Assembly of gamma radiation detection with directivity properties

    International Nuclear Information System (INIS)

    Stoica, M.; Talpalariu, C.

    2016-01-01

    An assembly of gamma radiation detection with directivity properties and small size enables the development of portable equipment or robots specialized in finding and signaling radioactively contaminated areas in case of nuclear incidents or decommissioning of nuclear installations. Directivity characteristic of the assembly of gamma radiation detection is very important when aiming to build an equipment for searching radioactively contaminated areas. In order to obtain a suitable directivity characteristics in terms of detection of gamma rays, it was necessary to construct a lead collimator with a cylindrical shape. The detector, preamplifier and amplifier pulse were placed inside the collimator and pulse discriminator circuit and power source were placed beside the collimator, all being disposed within the housing cylindrical experimental. A PIN photodiode type was used as a detector of gamma radiation. (authors)

  9. Ionizing radiation source detection by personal TLD

    International Nuclear Information System (INIS)

    Marinkovic, O.; Mirkov, Z.

    2002-01-01

    The Laboratory for personal dosimetry has about 3000 workers under control. The most of them work in medicine. Some institutions, as big health centers, have different ionizing radiation sources. It is usefull to analyze what has been the source of irradiation, special when appears a dosimeter with high dose. Personal dosimetry equipment is Harshaw TLD Reader Model 6600 and dosimeters consist of two chips LiF TLD-100 assembled in bar-coded cards which are wearing in holders with one tissue-equivalent filter (to determine H(10)) and skin-equivalent the other (to determine H(0.07)). The calibration dosimeters have been irradiated in holders by different sources: x-ray (for 80keV and 100keV), 6 0C o, 9 0S r (for different distances from beta source) and foton beem (at radiotherapy accelerator by 6MeV, 10MeV and 18MeV). The dose ratio for two LiF cristals was calculated and represented with graphs. So, it is possible to calculate the ratio H(10)/H(0.07) for a personal TLD and analyze what has been the source of irradiation. Also, there is the calibration for determination the time of irradiation, according to glow curve deconvolution

  10. ITRAP. Illicit trafficking radiation detection assessment program

    International Nuclear Information System (INIS)

    Beck, P.

    2001-02-01

    Illicit trafficking in nuclear materials (nuclear criminality) has become more and more a problem, due to the circulation of the a high number of radioactive sources and the big amount of nuclear material, particularly, caused by the changes of the organisational infrastructures to supervise these material within the successor states of the former Soviet Union. The IAEA data base counts at present more than 300 verified cases. The endangering cased thereby ranges from possible health defect for the publication to terrorists activities and production of nuclear weapons. In addition to the primary criminal reasons the illegal deposal of radioactive sources as salvage, scrap and others show a further problem, which has lead to severe accidents and lethal effects in the past (e.g. Goiana, Mexiko). As the study ITRAP (Illicit Trafficking Radiation Assessment Program) can show, also in Austria the cases of partly considerable contaminated scrap transports from neighbouring countries exists. Some countries have already under taken countermeasures (e.g. Monitoring at the Finnish-Russian and German-Polish border, border monitoring in Italy). The International Atomic Energy Agency (IAEA) has reacted on this actual problem by setting up a new program to fight against nuclear criminality and has suggested a pilot study for the practical test of border monitoring systems. Aim of the study was to work out the technical requirements and the practicability of an useful monitoring system at border crossings. The results of the study will be offered by the IAEA to the member states as international recommendations for border monitoring systems. (author)

  11. Radiation detection technique on the fishery foods

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Koji; Yano, Yutaka; Oikawa, Hiroshi [National Research Inst. of Fisheries Science, Yokohama (Japan)

    2000-02-01

    When muscles and myofibril are irradiated by gamma ray, Mg-ATPase activity increased with increasing of dose, but EDTA-ATPase decreased. If dose is very large, Ca-ATPase activity increased. The effects of state of protein on these phenomena were investigated. The muscles, myofibril and myosin B of Tilapia nilotica were used as samples. Change of Ca-ATPase, Mg-ATPase and EDTA-ATPase activity of myosin B by gamma-ray irradiation was the same as myofibril and muscles, but myosin B showed high sensitivity and each ATPase activity was changed by low dose. Accordingly, these values were more difficult to apply to detection technique of irradiation than state of muscle and myofibril. Collagen is known to degenerate and coagulate by gamma-ray irradiation. However, amount of hot water soluble collagen was increased with increasing of dose. (S.Y.)

  12. Conducted and radiated noise in detection devices

    International Nuclear Information System (INIS)

    Moisa, D.

    2001-01-01

    Conducted and radiated noise is an external noise which affects the quality of the signals of the detectors. An external noise can be reduced, usually, by shielding. This was the situation with 'older fashion' devices which uses boxes and coaxial cables. As the devices becomes more complex, the shielding of the detectors is more and more difficult and the transmission lines evolves from coaxial cables to twisted pair cables which are no more shielded. In such situation, the conducted and radiated noise (C and R noise) becomes important. Due to complexity of a real detector, the main work is based on experiments with components and simulations of some specific problems, associated with CDC detector. The first experiment was done to understand how the C and R noise is propagated. The emission device was a set of coils (between 3 and 5 turns with diameter from 10 to 50 mm) feed by an 74S140 driver. A pulse of about 8 ns width was generated. A coil of reception of about the same physical characteristics was used to see the emitted pulse. When the two coils are separated by about 80 cm, the receiver generated no signal. But, if along the two coils, a conductive material is introduced (a wire for instance), the receiver senses a signal. This signal is not changed too much if the wire is or not connected to ground. The explanation is simple: the pulse in the emitting coil produces an EM pulse which spreads in space. If a conductive material is around, the EM energy is received by that conductor and it is propagated at tens of meters with small attenuation. When this energy reaches the end of the conductor, it is radiated in space. If some other conductors are around, the energy is received and propagated by that conductors. This experiment was done for about 20 kinds of conductors (different coax cables, twisted-pair ribbons, power cables, metallic bars) and with many coils (different diameters and numbers of turns). It was measured the pk-to-pk level, decay constant and

  13. Effects of ionizing radiation on gastrointestinal function

    Energy Technology Data Exchange (ETDEWEB)

    Bertin, C; Dublineau, I; Griffiths, N M; Joubert, C; Linard, C; Martin, J M; Mathe, D; Scanff, P; Valette, P [CEA Centre d` Etudes de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire

    1994-10-01

    The aim of this project is to investigate the effects of ionizing radiation (<10 Gy) on several parameters of gastrointestinal function: (a) regulatory peptides; (b) pancreatic and biliary secretions and (c) electrolyte and lipid transport using both gamma alone (cobalt-60) and a mixture of gamma/neutron ({gamma}/N Silene reactor) in two animal models, the rat and the pig. Preliminary data in rats following gamma irradiation (2-8 Gy) show that plasma nurotensin gastrin releasing peptide and substance P are increased in a dose dependent manner most markedly between two and four days after exposure. Intestinal brush border marker enzyme activities (sucrose and leucine amino-peptidase) were also reduced. Such differences were more marked and persisted longer after {gamma}/N irradiation (2-4 Gy: +Pb: {gamma}/:N =0.2). Following the latter type of irradiation (4 Gy) plasma cholesterol increased as well as the cholesterol/phospholipid ratio. Analysis of cholesterol distribution in lipoprotein actions revealed a large increase in cholesterol carried b High Density Lipoprotein-1 (HDL1). In the pig following either type of irradiation the volumes of both pancreatic and biliary secretions were reduced. Irradiation of pigs with either {gamma} (6 Gy) alone or {gamma}/N (6 Gy: {gamma}/N I :1) resulted in a marked decrease in both brush border (sucrase: leucine aminopeptidase) and basolateral (sodium ump` aden late cyclase) enzyme activities. Vasoactive intestinal peptide (VIP) stimulated adenylate cyclase was markedly attenuated and in addition specific VIP binding was modified as shown by a reduction in receptor affinity. The significance of the data will be discussed and the importance of a new therapeutic strategies or new biological markers of radiation-induced gastrointestinal dysfunction.

  14. Method and circuit for stabilizing conversion gain of radiation detectors of a radiation detection system

    International Nuclear Information System (INIS)

    Stoub, E.W.

    1986-01-01

    A method is described for calibrating the gain of an array of radiation detectors of a radiation detection system comprising the steps of: (a) measuring in parallel for each radiation detector using a predetermined calibration point the energy map status, thereby obtaining an energy response vector whose elements correspond to the individual output of each radiation detector, each predetermined calibration point being a prescribed location corresponding to one of the radiation detectors; (b) multiplying that energy response vector with a predetermined deconvolution matrix, the deconvolution matrix being the inversion of a contribution matrix containing matrix elements C/sub IJ/, each such matrix element C/sub IJ/ of the contribution matrix representing the relative contribution level of a radiation detector j of the detection system for a point radiation source placed at a location i, thereby obtaining a gain vector product for the radiation detectors; (c) adjusting the gains of the radiation detectors with respect to the gain vector product such that a unity gain vector is essentially obtained; (d) measuring again the energy map status according to step (a); and (e) if the energy map status fails to essentially produce a unity gain vector repeat steps (a) to (d) until the energy map status substantially corresponds to unity

  15. Development of a novel gamma probe for detecting radiation direction

    Science.gov (United States)

    Pani, R.; Pellegrini, R.; Cinti, M. N.; Longo, M.; Donnarumma, R.; D'Alessio, A.; Borrazzo, C.; Pergola, A.; Ridolfi, S.; De Vincentis, G.

    2016-01-01

    Spatial localization of radioactive sources is currently a main issue interesting different fields, including nuclear industry, homeland security as well as medical imaging. It is currently achieved using different systems, but the development of technologies for detecting and characterizing radiation is becoming important especially in medical imaging. In this latter field, radiation detection probes have long been used to guide surgery, thanks to their ability to localize and quantify radiopharmaceutical uptake even deep in tissue. Radiolabelled colloid is injected into, or near to, the tumor and the surgeon uses a hand-held radiation detector, the gamma probe, to identify lymph nodes with radiopharmaceutical uptkake. The present work refers to a novel scintigraphic goniometric probe to identify gamma radiation and its direction. The probe incorporates several scintillation crystals joined together in a particular configuration to provide data related to the position of a gamma source. The main technical characteristics of the gamma locator prototype, i.e. sensitivity, spatial resolution and detection efficiency, are investigated. Moreover, the development of a specific procedure applied to the images permits to retrieve the source position with high precision with respect to the currently used gamma probes. The presented device shows a high sensitivity and efficiency to identify gamma radiation taking a short time (from 30 to 60 s). Even though it was designed for applications in radio-guided surgery, it could be used for other purposes, as for example homeland security.

  16. The problem of the detection threshold in radiation measurement

    International Nuclear Information System (INIS)

    Rose, E.; Wueneke, C.D.

    1983-01-01

    In all cases encountered in practical radiation measurement, the basic problem is to differentiate between the lowest measured value and the zero value (background, natural background radiation, etc.). For this purpose, on the mathematical side, tests based on hypotheses are to be applied. These will show the probability of differentiation between two values having the same random spread. By means of these tests and the corresponding error theory, a uniform treatment of the subject, applicable to all problems relating to measuring technique alike, can be found. Two basic concepts are found in this process, which have to be defined in terms of semantics and nomenclature: Decision threshold and detection threshold, or 'minimum detectable mean value'. At the decision threshold, one has to decide (with a given statistical error probability) whether a measured value is to be attributed to the background radiation, accepting the zero hypothesis, or whether this value differs significantly from the background radiation (error of 1rst kind). The minimum detectable mean value is the value which, with a given decision threshold, can be determined with sufficient significance to be a measured value and thus cannot be mistaken as background radiation (alternative hypothesis, error of 2nd kind). Normally, the two error types are of equal importance. It may happen, however, that one type of error gains more importance, depending on the approach. (orig.) [de

  17. Development of a novel gamma probe for detecting radiation direction

    International Nuclear Information System (INIS)

    Pani, R.; Pellegrini, R.; Cinti, M.N.; Longo, M.; Donnarumma, R.; Borrazzo, C.; D'Alessio, A.; Pergola, A.; Ridolfi, S.; Vincentis, G. De

    2016-01-01

    Spatial localization of radioactive sources is currently a main issue interesting different fields, including nuclear industry, homeland security as well as medical imaging. It is currently achieved using different systems, but the development of technologies for detecting and characterizing radiation is becoming important especially in medical imaging. In this latter field, radiation detection probes have long been used to guide surgery, thanks to their ability to localize and quantify radiopharmaceutical uptake even deep in tissue. Radiolabelled colloid is injected into, or near to, the tumor and the surgeon uses a hand-held radiation detector, the gamma probe, to identify lymph nodes with radiopharmaceutical uptkake. The present work refers to a novel scintigraphic goniometric probe to identify gamma radiation and its direction. The probe incorporates several scintillation crystals joined together in a particular configuration to provide data related to the position of a gamma source. The main technical characteristics of the gamma locator prototype, i.e. sensitivity, spatial resolution and detection efficiency, are investigated. Moreover, the development of a specific procedure applied to the images permits to retrieve the source position with high precision with respect to the currently used gamma probes. The presented device shows a high sensitivity and efficiency to identify gamma radiation taking a short time (from 30 to 60 s). Even though it was designed for applications in radio-guided surgery, it could be used for other purposes, as for example homeland security

  18. Multivariate Functional Data Visualization and Outlier Detection

    KAUST Repository

    Dai, Wenlin; Genton, Marc G.

    2017-01-01

    This article proposes a new graphical tool, the magnitude-shape (MS) plot, for visualizing both the magnitude and shape outlyingness of multivariate functional data. The proposed tool builds on the recent notion of functional directional outlyingness, which measures the centrality of functional data by simultaneously considering the level and the direction of their deviation from the central region. The MS-plot intuitively presents not only levels but also directions of magnitude outlyingness on the horizontal axis or plane, and demonstrates shape outlyingness on the vertical axis. A dividing curve or surface is provided to separate non-outlying data from the outliers. Both the simulated data and the practical examples confirm that the MS-plot is superior to existing tools for visualizing centrality and detecting outliers for functional data.

  19. Multivariate Functional Data Visualization and Outlier Detection

    KAUST Repository

    Dai, Wenlin

    2017-03-19

    This article proposes a new graphical tool, the magnitude-shape (MS) plot, for visualizing both the magnitude and shape outlyingness of multivariate functional data. The proposed tool builds on the recent notion of functional directional outlyingness, which measures the centrality of functional data by simultaneously considering the level and the direction of their deviation from the central region. The MS-plot intuitively presents not only levels but also directions of magnitude outlyingness on the horizontal axis or plane, and demonstrates shape outlyingness on the vertical axis. A dividing curve or surface is provided to separate non-outlying data from the outliers. Both the simulated data and the practical examples confirm that the MS-plot is superior to existing tools for visualizing centrality and detecting outliers for functional data.

  20. Functional assessment of cutaneous microvasculature after radiation

    International Nuclear Information System (INIS)

    Doll, C.; Durand, R.; Grulkey, W.; Sayer, S.; Olivotto, I.

    1999-01-01

    Background and purpose: To determine if laser Doppler flowmetry could be used to non-invasively evaluate microvasculature function after radiation therapy (RT), we assessed blood flow response to heating in women following RT after breast conservation.Materials and methods: Forty women with unilateral stage I/II breast cancer treated with conservative surgery and RT were evaluated at varying intervals post RT. Ten patients were retested after an interval of 55 to 57 months to assess reproducibility of the control data. A laser Doppler probe fitted into a heat source was used to non-invasively measure blood flow in a small area of skin on the treated breast and a matched area on the untreated side. The heating element increased skin surface temperature to 40C, permitting assessment of heat stress induced changes in blood flow.Results36 months post RT, there was no significant difference seen in relative blood flow between the irradiated and non-irradiated sides. Cutaneous blood flow response to the heat stress was very reproducible when women were reassessed 55 to 57 months after initial testing.Conclusions 36 months post RT. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  1. Calibration of a Stereo Radiation Detection Camera Using Planar Homography

    Directory of Open Access Journals (Sweden)

    Seung-Hae Baek

    2016-01-01

    Full Text Available This paper proposes a calibration technique of a stereo gamma detection camera. Calibration of the internal and external parameters of a stereo vision camera is a well-known research problem in the computer vision society. However, few or no stereo calibration has been investigated in the radiation measurement research. Since no visual information can be obtained from a stereo radiation camera, it is impossible to use a general stereo calibration algorithm directly. In this paper, we develop a hybrid-type stereo system which is equipped with both radiation and vision cameras. To calibrate the stereo radiation cameras, stereo images of a calibration pattern captured from the vision cameras are transformed in the view of the radiation cameras. The homography transformation is calibrated based on the geometric relationship between visual and radiation camera coordinates. The accuracy of the stereo parameters of the radiation camera is analyzed by distance measurements to both visual light and gamma sources. The experimental results show that the measurement error is about 3%.

  2. ANOLE Portable Radiation Detection System Field Test and Evaluation Campaign

    International Nuclear Information System (INIS)

    Hodge, Chris A.

    2007-01-01

    Handheld, backpack, and mobile sensors are elements of the Global Nuclear Detection System for the interdiction and control of illicit radiological and nuclear materials. They are used by the U.S. Department of Homeland Security (DHS) and other government agencies and organizations in various roles for border protection, law enforcement, and nonproliferation monitoring. In order to systematically document the operational performance of the common commercial off-the-shelf portable radiation detection systems, the DHS Domestic Nuclear Detection Office conducted a test and evaluation campaign conducted at the Nevada Test Site from January 18 to February 27, 2006. Named 'Anole', it was the first test of its kind in terms of technical design and test complexities. The Anole test results offer users information for selecting appropriate mission-specific portable radiation detection systems. The campaign also offered manufacturers the opportunity to submit their equipment for independent operationally relevant testing to subsequently improve their detector performance. This paper will present the design, execution, and methodologies of the DHS Anole portable radiation detection system test campaign

  3. Multi-sensor radiation detection, imaging, and fusion

    Energy Technology Data Exchange (ETDEWEB)

    Vetter, Kai [Department of Nuclear Engineering, University of California, Berkeley, CA 94720 (United States); Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2016-01-01

    Glenn Knoll was one of the leaders in the field of radiation detection and measurements and shaped this field through his outstanding scientific and technical contributions, as a teacher, his personality, and his textbook. His Radiation Detection and Measurement book guided me in my studies and is now the textbook in my classes in the Department of Nuclear Engineering at UC Berkeley. In the spirit of Glenn, I will provide an overview of our activities at the Berkeley Applied Nuclear Physics program reflecting some of the breadth of radiation detection technologies and their applications ranging from fundamental studies in physics to biomedical imaging and to nuclear security. I will conclude with a discussion of our Berkeley Radwatch and Resilient Communities activities as a result of the events at the Dai-ichi nuclear power plant in Fukushima, Japan more than 4 years ago. - Highlights: • .Electron-tracking based gamma-ray momentum reconstruction. • .3D volumetric and 3D scene fusion gamma-ray imaging. • .Nuclear Street View integrates and associates nuclear radiation features with specific objects in the environment. • Institute for Resilient Communities combines science, education, and communities to minimize impact of disastrous events.

  4. Organic materials and devices for detecting ionizing radiation

    Science.gov (United States)

    Doty, F Patrick [Livermore, CA; Chinn, Douglas A [Livermore, CA

    2007-03-06

    A .pi.-conjugated organic material for detecting ionizing radiation, and particularly for detecting low energy fission neutrons. The .pi.-conjugated materials comprise a class of organic materials whose members are intrinsic semiconducting materials. Included in this class are .pi.-conjugated polymers, polyaromatic hydrocarbon molecules, and quinolates. Because of their high resistivities (.gtoreq.10.sup.9 ohmcm), these .pi.-conjugated organic materials exhibit very low leakage currents. A device for detecting and measuring ionizing radiation can be made by applying an electric field to a layer of the .pi.-conjugated polymer material to measure electron/hole pair formation. A layer of the .pi.-conjugated polymer material can be made by conventional polymer fabrication methods and can be cast into sheets capable of covering large areas. These sheets of polymer radiation detector material can be deposited between flexible electrodes and rolled up to form a radiation detector occupying a small volume but having a large surface area. The semiconducting polymer material can be easily fabricated in layers about 10 .mu.m to 100 .mu.m thick. These thin polymer layers and their associated electrodes can be stacked to form unique multi-layer detector arrangements that occupy small volume.

  5. Detection of ultraviolet radiation using tissue equivalent radiochromic gel materials

    International Nuclear Information System (INIS)

    Bero, M A; Abukassem, I

    2009-01-01

    Ferrous Xylenol-orange Gelatin gel (FXG) is known to be sensitive to ionising radiation such as γ and X-rays. The effect of ionising radiation is to produce an increase in the absorption over a wide region of the visible spectrum, which is proportional to the absorbed dose. This study demonstrates that FXG gel is sensitive to ultraviolet radiation and therefore it could functions as UV detector. Short exposure to UV radiation produces linear increase in absorption measured at 550nm, however high doses of UV cause the ion indicator colour to fad away in a manner proportional to the incident UV energy. Light absorbance increase at the rate of 1.1% per minute of irradiation was monitored. The exposure level at which the detector has linear response is comparable to the natural summer UV radiation. Evaluating the UV ability to pass through tissue equivalent gel materials shows that most of the UV gets absorbed in the first 5mm of the gel materials, which demonstrate the damaging effects of this radiation type on human skin and eyes. It was concluded that FXG gel dosimeter has the potential to offer a simple, passive ultraviolet radiation detector with sensitivity suitable to measure and visualises the natural sunlight UV exposure directly by watching the materials colour changes.

  6. Detection of ultraviolet radiation using tissue equivalent radiochromic gel materials

    Science.gov (United States)

    Bero, M. A.; Abukassem, I.

    2009-05-01

    Ferrous Xylenol-orange Gelatin gel (FXG) is known to be sensitive to ionising radiation such as γ and X-rays. The effect of ionising radiation is to produce an increase in the absorption over a wide region of the visible spectrum, which is proportional to the absorbed dose. This study demonstrates that FXG gel is sensitive to ultraviolet radiation and therefore it could functions as UV detector. Short exposure to UV radiation produces linear increase in absorption measured at 550nm, however high doses of UV cause the ion indicator colour to fad away in a manner proportional to the incident UV energy. Light absorbance increase at the rate of 1.1% per minute of irradiation was monitored. The exposure level at which the detector has linear response is comparable to the natural summer UV radiation. Evaluating the UV ability to pass through tissue equivalent gel materials shows that most of the UV gets absorbed in the first 5mm of the gel materials, which demonstrate the damaging effects of this radiation type on human skin and eyes. It was concluded that FXG gel dosimeter has the potential to offer a simple, passive ultraviolet radiation detector with sensitivity suitable to measure and visualises the natural sunlight UV exposure directly by watching the materials colour changes.

  7. Flexible Receiver Radiation Detection System (FRRDS) Users Manual

    International Nuclear Information System (INIS)

    Troyer, G.L.

    1996-01-01

    The Flexible Receiver Radiation Detection System (FRRDS) comprises a control computer, a remote data acquisition subsystem, and three hyperpure germanium gamma radiation detectors. The scope of this document is the description of various steps for the orderly start-up, use, and shutdown of the FRRDS. Only those items necessary for these oprations are included. This document is a companion to WHC-SD-W151-UM-002, 'Operating Instructions for the 42 Inch Flexible Receiver,' WHC-SD-W151-UM-003, 'Operating Instructions for the 4-6 Inch Flexible Receiver,' and the vendor supplied system users guide (Ref. 6)

  8. Development and deployment of the Collimated Directional Radiation Detection System

    Science.gov (United States)

    Guckes, Amber L.; Barzilov, Alexander

    2017-09-01

    The Collimated Directional Radiation Detection System (CDRDS) is capable of imaging radioactive sources in two dimensions (as a directional detector). The detection medium of the CDRDS is a single Cs2LiYCl6:Ce3+ scintillator cell enriched in 7Li (CLYC-7). The CLYC-7 is surrounded by a heterogeneous high-density polyethylene (HDPE) and lead (Pb) collimator. These materials make-up a coded aperture inlaid in the collimator. The collimator is rotated 360° by a stepper motor which enables time-encoded imaging of a radioactive source. The CDRDS is capable of spectroscopy and pulse shape discrimination (PSD) of photons and fast neutrons. The measurements of a radioactive source are carried out in discrete time steps that correlate to the angular rotation of the collimator. The measurement results are processed using a maximum likelihood expectation (MLEM) algorithm to create an image of the measured radiation. This collimator design allows for the directional detection of photons and fast neutrons simultaneously by utilizing only one CLYC-7 scintillator. Directional detection of thermal neutrons can also be performed by utilizing another suitable scintillator. Moreover, the CDRDS is portable, robust, and user friendly. This unit is capable of utilizing wireless data transfer for possible radiation mapping and network-centric applications. The CDRDS was tested by performing laboratory measurements with various gamma-ray and neutron sources.

  9. Current trends in gamma radiation detection for radiological emergency response

    Science.gov (United States)

    Mukhopadhyay, Sanjoy; Guss, Paul; Maurer, Richard

    2011-09-01

    Passive and active detection of gamma rays from shielded radioactive materials, including special nuclear materials, is an important task for any radiological emergency response organization. This article reports on the current trends and status of gamma radiation detection objectives and measurement techniques as applied to nonproliferation and radiological emergencies. In recent years, since the establishment of the Domestic Nuclear Detection Office by the Department of Homeland Security, a tremendous amount of progress has been made in detection materials (scintillators, semiconductors), imaging techniques (Compton imaging, use of active masking and hybrid imaging), data acquisition systems with digital signal processing, field programmable gate arrays and embedded isotopic analysis software (viz. gamma detector response and analysis software [GADRAS]1), fast template matching, and data fusion (merging radiological data with geo-referenced maps, digital imagery to provide better situational awareness). In this stride to progress, a significant amount of inter-disciplinary research and development has taken place-techniques and spin-offs from medical science (such as x-ray radiography and tomography), materials engineering (systematic planned studies on scintillators to optimize several qualities of a good scintillator, nanoparticle applications, quantum dots, and photonic crystals, just to name a few). No trend analysis of radiation detection systems would be complete without mentioning the unprecedented strategic position taken by the National Nuclear Security Administration (NNSA) to deter, detect, and interdict illicit trafficking in nuclear and other radioactive materials across international borders and through the global maritime transportation-the so-called second line of defense.

  10. Performance test of SKIROC II ASIC chip for the radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Jun, W. J.; Namgoong, H.; Kim, B. K.; Song, H. S.; Kim, H. S.; Lee, S. H.; Choi, H. J.; Ghergherehchi, M.; Chai, J. S. [Sungkyunkwan University, Suwon (Korea, Republic of)

    2017-04-15

    There is a PCB board called FEV8 board which can readout analog signal from any energy source, and amplify it for signal processing. For precise detection, the board had been designed to operate in wide range of energy condition, with high-resolutive detection performance. This function has the possibility of the utilization for the radiation detection. The channels of the prototype board must be evaluated to make sure that the board is perfect or not. This research had made an progress for the radiation detection as well as the electronics of the intricate combination of the measurement instrumentations. The number of the noisy channels had been measured for threshold scan, and every channels in the board had been evaluated. By improving the experimental conditions such as test script in Linux system or well designed ground condition of the test bench, much more clean data will be able to be acquisited.

  11. Influence functionals and black body radiation

    OpenAIRE

    Anglin, J. R.

    1993-01-01

    The Feynman-Vernon formalism is used to obtain a microscopic, quantum mechanical derivation of black body radiation, for a massless scalar field in 1+1 dimensions, weakly coupled to an environment of finite size. The model exhibits the absorption, thermal equilibrium, and emission properties of a canonical black body, but shows that the thermal radiation propagates outwards from the body, with the Planckian spectrum applying inside a wavefront region of finite thickness. The black body enviro...

  12. Radiation detection using the color changes of lilac spodumene

    International Nuclear Information System (INIS)

    Oliveira, Raquel A.P.; Mello, Ana Carolina S.; Lima, Hestia R.B.R.; Campos, Simara Santos; Souza, Suzana O.

    2009-01-01

    The use of radiation in industrial processes currently offers several advantages in the field of sterilization of medical and pharmaceuticals products, the preservation of food, and a variety of other products widely used in modern society. A dosimetry of confidence is a key parameter for the quality assurance of radiation processing and the irradiated products. This work investigates dosimetric properties in natural spodumene, LiAlSi 2 O 6 , called kunzite, from Minas Gerais State, Brazil. After X irradiation on the samples in powder form was detected a change in color of the crystal where the dose received. This makes a possible viability of this material is applied in research on development of radiation detectors using the change in color of purple spodumene. (author)

  13. Investigation of salivary function and oral microbiota of radiation caries-free people with nasopharyngeal carcinoma.

    Directory of Open Access Journals (Sweden)

    Jingyang Zhang

    Full Text Available Radiation caries have been reported to be correlated with radiotherapy-induced destruction of salivary function and changes in oral microbiota. There have been no published reports detailing patients who have remained radiation caries-free following radiotherapy for nasopharyngeal carcinoma. The aim of this study was to investigate the relationship between salivary function, oral microbiota and the absence of radiation caries. Twelve radiation caries-free patients and nine patients exhibiting radiation caries following irradiated nasopharyngeal carcinoma were selected. V40, the dose at which the volume of the contralateral parotid gland receives more than 40 Gy, was recorded. Stimulated saliva flow rate, pH values and buffering capacity were examined to assess salivary function. Stimulated saliva was used for molecular profiling by Denaturing Gradient Gel Electrophoresis. Mutans streptococci and Lactobacilli in saliva were also cultivated. There were no significant differences in V40 between radiation caries-free individuals and those with radiation caries. Compared with normal values, the radiation caries-free group had significantly decreased simulated saliva flow rate, while there were no significant differences in the saliva pH value and buffering capacity. Similar results were observed in the radiation caries group. There was no statistical difference in microbial diversity, composition and log CFU counts in cultivation from the radiation caries-free group and the radiation caries group. Eleven genera were detected in these two groups, among which Streptococcus spp. and Neisseria spp. had the highest distribution. Our results suggest that changes in salivary function and in salivary microbiota do not explain the absence of radiation caries in radiation caries-free individuals.

  14. EPR detection of foods preserved with ionizing radiation

    Science.gov (United States)

    Stachowicz, W.; Burlinska, G.; Michalik, J.

    1998-06-01

    The applicability of the epr technique for the detection of dried vegetables, mushrooms, some spices, flavour additives and some condiments preserved with ionizing radiation is discussed. The epr signals recorded after exposure to gamma rays and to beams of 10 MeV electrons from linac are stable, intense and specific enough as compared with those observed with nonirradiated samples and could be used for the detection of irradiation. However, stability of radiation induced epr signals produced in these foods depends on storage condition. No differences in shapes (spectral parameters) and intensities of the epr spectra recorded with samples exposed to the same doses of gamma rays ( 60Co) and 10 MeV electrons were observed

  15. EPR detection of foods preserved with ionizing radiation

    International Nuclear Information System (INIS)

    Stachowicz, W.; Burlinska, G.; Michalik, J.

    1998-01-01

    The applicability of the epr technique for the detection of dried vegetables, mushrooms, some spices, flavour additives and some condiments preserved with ionizing radiation is discussed. The epr signals recorded after exposure to gamma rays and to the beams of 10 MeV electrons from linac are stable, intense and specific enough as compared with those observed with nonirradiated samples and could be used for the detection of irradiation. However, stability of radiation induced epr signals produced in these foods depends on storage condition. No differences in shapes (spectral parameters) and intensities of the epr spectra recorded with samples exposed to the same doses of gamma rays ( 60 Co) and 10 MeV electrons were observed

  16. Position sensitive detection of neutrons in high radiation background field.

    Science.gov (United States)

    Vavrik, D; Jakubek, J; Pospisil, S; Vacik, J

    2014-01-01

    We present the development of a high-resolution position sensitive device for detection of slow neutrons in the environment of extremely high γ and e(-) radiation background. We make use of a planar silicon pixelated (pixel size: 55 × 55 μm(2)) spectroscopic Timepix detector adapted for neutron detection utilizing very thin (10)B converter placed onto detector surface. We demonstrate that electromagnetic radiation background can be discriminated from the neutron signal utilizing the fact that each particle type produces characteristic ionization tracks in the pixelated detector. Particular tracks can be distinguished by their 2D shape (in the detector plane) and spectroscopic response using single event analysis. A Cd sheet served as thermal neutron stopper as well as intensive source of gamma rays and energetic electrons. Highly efficient discrimination was successful even at very low neutron to electromagnetic background ratio about 10(-4).

  17. EPR detection of foods preserved with ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Stachowicz, W.; Burlinska, G.; Michalik, J

    1998-06-01

    The applicability of the epr technique for the detection of dried vegetables, mushrooms, some spices, flavour additives and some condiments preserved with ionizing radiation is discussed. The epr signals recorded after exposure to gamma rays and to the beams of 10 MeV electrons from linac are stable, intense and specific enough as compared with those observed with nonirradiated samples and could be used for the detection of irradiation. However, stability of radiation induced epr signals produced in these foods depends on storage condition. No differences in shapes (spectral parameters) and intensities of the epr spectra recorded with samples exposed to the same doses of gamma rays ({sup 60}Co) and 10 MeV electrons were observed.

  18. Fourier expansions and multivariable Bessel functions concerning radiation programmes

    International Nuclear Information System (INIS)

    Dattoli, G.; Richetta, M.; Torre, A.; Chiccoli, C.; Lorenzutta, S.; Maino, G.

    1996-01-01

    The link between generalized Bessel functions and other special functions is investigated using the Fourier series and the generalized Jacobi-Anger expansion. A new class of multivariable Hermite polynomials is then introduced and their relevance to physical problems discussed. As an example of the power of the method, applied to radiation physics, we analyse the role played by multi-variable Bessel functions in the description of radiation emitted by a charge constrained to a nonlinear oscillation. (author)

  19. Radiation Detection System for Prevention of Radiological and Nuclear Terrorism

    International Nuclear Information System (INIS)

    Kwak, Sung-Woo; Yoo, Ho-Sik; Jang, Sung-Sun; Kim, Jae-Kwang; Kim, Jung-Soo

    2007-01-01

    After the September 11 terrorist attack, the threat of a potential for a radiological or nuclear terrorist attack became more apparent. The threats relating to radiological or nuclear materials include a Radiological Dispersion Device (RDD), an Improved Nuclear Device (IND) or a State Nuclear Device (such as a Soviet manufactured suitcase nuclear weapon). For more effective countermeasures against the disaster, multilayer protection concept - prevention of smuggling of radioactive or nuclear material into our country through seaports or airports, detection and prevention of the threat materials in transit on a road, and prevention of their entry into a target building - is recommended. Due to different surrounding circumstances of where detection system is deployed, different types of radiation detection systems are required. There have been no studies on characteristics of detection equipment required under Korean specific conditions. This paper provides information on technical requirements of radiation detection system to achieve multi-layer countermeasures for the purpose of protecting the public and environment against radiological and nuclear terrorism

  20. Method for detecting radiation dose utilizing thermoluminescent material

    International Nuclear Information System (INIS)

    Miller, S.D.; McDonald, J.C.; Eichner, F.N.; Durham, J.S.

    1992-01-01

    The amount of ionizing radiation to which a thermoluminescent material has been exposed is determined by first cooling the thermoluminescent material and then optically stimulating the thermoluminescent material by exposure to light. Visible light emitted by the thermoluminescent material as it is allowed to warm up to room temperature is detected and counted. The thermoluminescent material may be annealed by exposure to ultraviolet light. 5 figs

  1. Polarization sensitive detection of 100 GHz radiation by high mobility field-effect transistors

    International Nuclear Information System (INIS)

    Sakowicz, M.; Lusakowski, J.; Karpierz, K.; Grynberg, M.; Knap, W.; Gwarek, W.

    2008-01-01

    Detection of 100 GHz electromagnetic radiation by a GaAs/AlGaAs high electron mobility field-effect transistor was investigated at 300 K as a function of the angle α between the direction of linear polarization of the radiation and the symmetry axis of the transistor. The angular dependence of the detected signal was found to be A 0 cos 2 (α-α 0 )+C with A 0 , α 0 , and C dependent on the electrical polarization of the transistor gate. This dependence is interpreted as due to excitation of two crossed phase-shifted oscillators. A response of the transistor chip (including bonding wires and the substrate) to 100 GHz radiation was numerically simulated. Results of calculations confirmed experimentally observed dependencies and showed that the two oscillators result from an interplay of 100 GHz currents defined by the transistor impedance together with bonding wires and substrate related modes

  2. Additive Manufacturing Materials Study for Gaseous Radiation Detection

    Energy Technology Data Exchange (ETDEWEB)

    Steer, C.A.; Durose, A.; Boakes, J. [AWE Aldermaston, Reading, Berkshire, RG7 4PR (United Kingdom)

    2015-07-01

    Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

  3. Additive Manufacturing Materials Study for Gaseous Radiation Detection

    International Nuclear Information System (INIS)

    Steer, C.A.; Durose, A.; Boakes, J.

    2015-01-01

    Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

  4. Detection and spectral measurements of coherent synchrotron radiation at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Behrens, Christopher

    2010-02-15

    The operation of high-gain free-electron laser (FEL) underlies tremendous demands on high quality electron beams with high peak currents. At the Free-Electron-Laser in Hamburg (FLASH), two magnetic bunch compressors are used to compress the electron bunches longitudinally. In the bunch compressor magnets, these short electron bunches generate coherent synchrotron radiation (CSR). This CSR contains information on the longitudinal bunch profile, which is relevant for driving an FEL. In order to investigate coherent synchrotron radiation at the second bunch compressor BC3 at FLASH, a new setup behind the last dipole was installed. For the detection of coherent synchrotron radiation, which is emitted in the infrared regime, pyroelectric detectors were used. These pyroelectric detectors have been calibrated at the free-electron laser FELIX in the wavelength range from 5 {mu}m to 110 {mu}m. For characterisation of the emitted radiation, a transverse scanning device was used to measure the transverse intensity distribution. Various transmission filters were used to obtain additional information about the spectral content. In order to get spectral information with high resolution over a wide wavelength range, a rotating mirror spectrometer using reflective blazed gratings was installed. Using this spectrometer, the first spectral measurements of coherent synchrotron radiation at FLASH in a wavelength range from 10 {mu}m to 160 {mu}m were done. (orig.)

  5. Detection and spectral measurements of coherent synchrotron radiation at FLASH

    International Nuclear Information System (INIS)

    Behrens, Christopher

    2010-02-01

    The operation of high-gain free-electron laser (FEL) underlies tremendous demands on high quality electron beams with high peak currents. At the Free-Electron-Laser in Hamburg (FLASH), two magnetic bunch compressors are used to compress the electron bunches longitudinally. In the bunch compressor magnets, these short electron bunches generate coherent synchrotron radiation (CSR). This CSR contains information on the longitudinal bunch profile, which is relevant for driving an FEL. In order to investigate coherent synchrotron radiation at the second bunch compressor BC3 at FLASH, a new setup behind the last dipole was installed. For the detection of coherent synchrotron radiation, which is emitted in the infrared regime, pyroelectric detectors were used. These pyroelectric detectors have been calibrated at the free-electron laser FELIX in the wavelength range from 5 μm to 110 μm. For characterisation of the emitted radiation, a transverse scanning device was used to measure the transverse intensity distribution. Various transmission filters were used to obtain additional information about the spectral content. In order to get spectral information with high resolution over a wide wavelength range, a rotating mirror spectrometer using reflective blazed gratings was installed. Using this spectrometer, the first spectral measurements of coherent synchrotron radiation at FLASH in a wavelength range from 10 μm to 160 μm were done. (orig.)

  6. Radiation processing and functional properties of soybean (Glycine max)

    International Nuclear Information System (INIS)

    Pednekar, Mrinal; Das, Amit K.; Rajalakshmi, V; Sharma, Arun

    2010-01-01

    Effect of radiation processing (10, 20 and 30 kGy) on soybean for better utilization was studied. Radiation processing reduced the cooking time of soybean and increased the oil absorption capacity of soy flour without affecting its proximate composition. Irradiation improved the functional properties like solubility, emulsification activity and foam stability of soybean protein isolate. The value addition effect of radiation processing has been discussed for the products (soy milk, tofu and tofu fortified patties) prepared from soybean.

  7. Exploiting Novel Radiation-Induced Electromagnetic Material Changes for Remote Detection and Monitoring: Final Progress Report

    Science.gov (United States)

    2016-04-01

    Exploiting Novel Radiation -Induced Electromagnetic Material Changes for Remote Detection and Monitoring: Final Progress Report Distribution...assess the effects of ionizing radiation on at least three classes of electromagnetic materials. The proposed approach for radiation detection was...that was desired to be monitored remotely. Microwave or low millimeter wave electromagnetic radiation would be used to interrogate the device

  8. Human Portable Radiation Detection System Communications Package Evaluation

    International Nuclear Information System (INIS)

    Morgen, Gerald P.; Peterson, William W.

    2009-01-01

    Testing and valuation of the Human Portable Radiation Detection System Communications Package for the US Coast Guard. The main components of the HCP field kit are an Archer Field PC(reg s ign) and an Iridium satellite phone, along with various charging components and cables. The Archer Field PC has an Enfora Global System for Mobile/General Packet Radio System (GSM/GPRS) wireless cellular modem installed via the compact flash (CF) port. The Iridium satellite phone has a serial communication interface attached. The Archer Field PC is running Windows Mobile(reg s ign) 5.0 operating system. Included Microsoft products are Excel(reg s ign) Mobile, PowerPoint(reg s ign) Mobile, Word(reg s ign) Mobile, and Internet Explorer(reg s ign) Mobile. There is an Outlook(reg s ign) Email program that can be accessed via sending a file or the Messaging link. The Cambridge Computer Corporation vxHpc program is installed to provide a Hyperterm-like software product. vxHpc supports multiple communication protocols. An AT and T SIM card was provided for the GSM wireless cellular modem. A check with AT and T determined the SIM card was not activated to provide cellular service. The Iridium satellite phone did not have a SIM card and has no service. The Archer Field PC boots into a HCP program, displaying the Main Menu. The following actions can be executed by selecting the appropriate box: Spectrum Download, Spectrum Transfer, and Admin Control. The Spectrum Download function uses the serial communication port to download data files from another device, such as a Radiation Isotope Identification Device (RIID). The Spectrum Transfer function uses either the installed wireless cellular modem or the Iridium satellite phone (attached to the serial communication port) to send data files to a computer modem at the Laboratories and Scientific Services (LSS). The Admin Control function allows entering phone numbers and data file deletion. PNNL recommends that DNDO (and/or CG) contact Sanmina

  9. Detection of gravitational radiation by the Doppler tracking of spacecraft

    International Nuclear Information System (INIS)

    Mashhoon, B.

    1979-01-01

    It has been suggested that the residual Doppler shift in the precision electromagnetic tracking of spacecraft be used to search for gravitational radiation that may be incident on the Earth-spacecraft system. The influence of a gravitational wave on the Doppler shift is calculated, and it is found that the residual shift is dominated by two terms: one is due to the passage of electromagnetic waves through the gravitational radiation field, and the other depends on the change in the relative velocity of the Earth and the spacecraft caused by the external wave. A detailed analysis is given of the influence of gravitational radiation on a binary system with an orbital size small compared to the wavelength of the incident radiation. It is shown that, as a consequence of the interaction with the external wave, the system makes a transition from one Keplerian orbit into another which, in general, has a different energy and angular momentum. It is therefore proposed to search for such effects in the solar system. Observations of the orbit of an artificial Earth satellite, the lunar orbit, and especially the planetary orbits offer exciting possibilities for the detection of gravitational waves of various wavelengths. From the results of the lunar laser ranging experiment and the range measurement to Mars, certain interesting limits may be established on the frequency of incidence of gravitational waves of a given flux on the Earth-Moon and the Earth-Mars systems. This is followed by a brief and preliminary analysis of the possibility of detecting gravitational radiation by measuring a residual secular Doppler shift in the satellite-to-satellite Doppler tracking of two counterorbiting drag-free spacecraft around the Earth as in the Van Patten-Everitt experiment

  10. A dual-sided coded-aperture radiation detection system

    International Nuclear Information System (INIS)

    Penny, R.D.; Hood, W.E.; Polichar, R.M.; Cardone, F.H.; Chavez, L.G.; Grubbs, S.G.; Huntley, B.P.; Kuharski, R.A.; Shyffer, R.T.; Fabris, L.; Ziock, K.P.; Labov, S.E.; Nelson, K.

    2011-01-01

    We report the development of a large-area, mobile, coded-aperture radiation imaging system for localizing compact radioactive sources in three dimensions while rejecting distributed background. The 3D Stand-Off Radiation Detection System (SORDS-3D) has been tested at speeds up to 95 km/h and has detected and located sources in the millicurie range at distances of over 100 m. Radiation data are imaged to a geospatially mapped world grid with a nominal 1.25- to 2.5-m pixel pitch at distances out to 120 m on either side of the platform. Source elevation is also extracted. Imaged radiation alarms are superimposed on a side-facing video log that can be played back for direct localization of sources in buildings in urban environments. The system utilizes a 37-element array of 5x5x50 cm 3 cesium-iodide (sodium) detectors. Scintillation light is collected by a pair of photomultiplier tubes placed at either end of each detector, with the detectors achieving an energy resolution of 6.15% FWHM (662 keV) and a position resolution along their length of 5 cm FWHM. The imaging system generates a dual-sided two-dimensional image allowing users to efficiently survey a large area. Imaged radiation data and raw spectra are forwarded to the RadioNuclide Analysis Kit (RNAK), developed by our collaborators, for isotope ID. An intuitive real-time display aids users in performing searches. Detector calibration is dynamically maintained by monitoring the potassium-40 peak and digitally adjusting individual detector gains. We have recently realized improvements, both in isotope identification and in distinguishing compact sources from background, through the installation of optimal-filter reconstruction kernels.

  11. Radiation detection and situation management by distributed sensor networks

    International Nuclear Information System (INIS)

    Jan, Frigo; Mielke, Angela; Cai, D. Michael

    2009-01-01

    Detection of radioactive materials in an urban environment usually requires large, portal-monitor-style radiation detectors. However, this may not be a practical solution in many transport scenarios. Alternatively, a distributed sensor network (DSN) could complement portal-style detection of radiological materials through the implementation of arrays of low cost, small heterogeneous sensors with the ability to detect the presence of radioactive materials in a moving vehicle over a specific region. In this paper, we report on the use of a heterogeneous, wireless, distributed sensor network for traffic monitoring in a field demonstration. Through wireless communications, the energy spectra from different radiation detectors are combined to improve the detection confidence. In addition, the DSN exploits other sensor technologies and algorithms to provide additional information about the vehicle, such as its speed, location, class (e.g. car, truck), and license plate number. The sensors are in-situ and data is processed in real-time at each node. Relevant information from each node is sent to a base station computer which is used to assess the movement of radioactive materials

  12. Sweat gland function as a measure of radiation change

    International Nuclear Information System (INIS)

    Pigott, K.H.; Dische, S.; Saunders, M.I.; Vojnovic, B.

    2000-01-01

    Radiotherapy may result in dryness of the skin even when no other change can be detected. We describe a system for recording the electrical conductance of skin as a measure of sweat gland function. In 22 normal volunteers close agreement was obtained between measurements obtained from comparable sites on both sides of the chest. Measurements were subsequently made in 38 patients treated by radiotherapy to one side of the chest for tumours of the breast or lung using one of five different fractionation schedules. Simultaneous readings were obtained from both sides of the chest with the non irradiated side acting as a control. A dose response relationship was demonstrated: five patients who received the equivalent total dose of 15 Gy in 2-Gy fractions showed no change in conductance. Sixteen out of 23 who received an equivalent total dose of 42-46 Gy in 2-Gy fractions had a greater than 22% reduction in mean skin conductance compared with that of the control areas despite the skin appearing normal in the large majority. Marked changes in skin conductance were seen after higher total doses. In a prospective study 18 women receiving breast irradiation underwent weekly readings during treatment. A mean reduction of 40% in skin conductance was noted by the end of the second week of treatment prior to any clinical evidence of radiation change. Skin conductance returned to normal in 44% of patients by 6 months. In the remainder, those patients who showed the greatest reduction in skin conductance during treatment demonstrated the least recovery. Changes in sweat gland function can be detected and quantified in skin which may otherwise appear normal. Differences may so be demonstrated between areas treated using different fractionation schedules and the method may be applied to the detection during radiotherapy of unusually sensitive patient. (author)

  13. Particle and photon detection for a neutron radiative decay experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gentile, T.R. [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States)], E-mail: thomas.gentile@nist.gov; Dewey, M.S.; Mumm, H.P.; Nico, J.S.; Thompson, A.K. [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Chupp, T.E. [University of Michigan, Ann Arbor, MI 48109 (United States); Cooper, R.L. [University of Michigan, Ann Arbor, MI 48109 (United States)], E-mail: cooperrl@umich.edu; Fisher, B.M.; Kremsky, I.; Wietfeldt, F.E. [Tulane University, New Orleans, LA 70118 (United States); Kiriluk, K.G.; Beise, E.J. [University of Maryland, College Park, MD 20742 (United States)

    2007-08-21

    We present the particle and photon detection methods employed in a program to observe neutron radiative beta-decay. The experiment is located at the NG-6 beam line at the National Institute of Standards and Technology Center for Neutron Research. Electrons and protons are guided by a 4.6 T magnetic field and detected by a silicon surface barrier detector. Photons with energies between 15 and 750 keV are registered by a detector consisting of a bismuth germanate scintillator coupled to a large area avalanche photodiode. The photon detector operates at a temperature near 80 K in the bore of a superconducting magnet. We discuss CsI as an alternative scintillator, and avalanche photodiodes for direct detection of photons in the 0.1-10 keV range.

  14. Assessment of Radiation Background Variation for Moving Detection Systems

    Energy Technology Data Exchange (ETDEWEB)

    Miller, James Christopher [Los Alamos National Laboratory; Rennie, John Alan [Los Alamos National Laboratory; Toevs, James Waldo [Los Alamos National Laboratory; Wallace, Darrin J. [Los Alamos National Laboratory; Abhold, Mark Edward [Los Alamos National Laboratory

    2015-07-13

    The introduction points out that radiation backgrounds fluctuate across very short distances: factors include geology, soil composition, altitude, building structures, topography, and other manmade structures; and asphalt and concrete can vary significantly over short distances. Brief descriptions are given of the detection system, experimental setup, and background variation measurements. It is concluded that positive and negative gradients can greatly reduce the detection sensitivity of an MDS: negative gradients create opportunities for false negatives (nondetection), and positive gradients create a potentially unacceptable FAR (above 1%); the location of use for mobile detection is important to understand; spectroscopic systems provide more information for screening out false alarms and may be preferred for mobile use; and mobile monitor testing at LANL accounts for expected variations in the background.

  15. A novel mobile system for radiation detection and monitoring

    Science.gov (United States)

    Biafore, Mauro

    2014-05-01

    A novel mobile system for real time, wide area radiation surveillance has been developed within the REWARD project, financed within the FP7 programme, theme SEC-2011.1.5-1 (Development of detection capabilities of difficult to detect radioactive sources and nuclear materials - Capability Project). The REWARD sensing units are small, mobile portable units with low energy consumption, which consist of new miniaturized solid-state radiation sensors: a CdZnTe detector for gamma radiation and a high efficiency neutron detector based on novel silicon technologies. The sensing unit is integrated by a wireless communication interface to send the data remotely to a monitoring base station as well as a GPS system to calculate the position of the tag. The system also incorporates middleware and high-level software to provide web-service interfaces for the exchange of information. A central monitoring and decision support system has been designed to process the data from the sensing units and to compare them with historical record in order to generate an alarm when an abnormal situation is detected. A security framework ensures protection against unauthorized access to the network and data, ensuring the privacy of the communications and contributing to the overall robustness and reliability of the REWARD system. The REWARD system has been designed for many different scenarios such as nuclear terrorism threats, lost radioactive sources, radioactive contamination or nuclear accidents. It can be deployed in emergency units and in general in any type of mobile or static equipment, but also inside public/private buildings or infrastructures. The complete system is scalable in terms of complexity and cost and offers very high precision on both the measurement and the location of the radiation. The modularity and flexibility of the system allows for a realistic introduction to the market. Authorities may start with a basic, low cost system and increase the complexity based on their

  16. Synthesis of Functional Materials by Radiation

    International Nuclear Information System (INIS)

    Noh, Y. C.; Kang, P. H.; Choi, J. H.

    2006-06-01

    The radiation crosslinking, grafting, curing and degradation can be easily adjusted and is easily reproducible by controlling the radiation dose. These studies aim to develop new biomaterials such as wound healing, tissue engineering and antiadhesion barrier. The effect of thermal treatment and irradiation on the physico-chemical properties of ultra-high molecular weight polyethylene (UHMWPE) used in orthopedic implants was investigated. If a large amount of polymer radicals remain trapped after the irradiation of ultra-high molecular weight polyethylene (UHMWPE), the radicals may significantly alter the physical properties of UHMWPE during long shelf storage and implantation for a long time period. UHMWPE irradiated in the molten state had a higher crosslinking extent and a lower wear rate than one irradiated in the room temperature. The radiation grafting technology can develop membrane of fuel cell and Li secondary battery and heavy metal absorbents. Proton exchange membranes were prepared by γ-irradiation-induced grafting of styrene into fluorinated polymer films and subsequent sulfonation. Results of the present work suggest that radiation induced-graft polymerization can be used as alternative method to blending to prepare polymer electrolyte membranes for lithium battery applications. The polypropylene-based compatibilizers, polypropylene-g-maleic anhydride (PP-MAH), polypropylene-g-maleic anhydride/styrene (PP-St/MAH), and polypropylene-g-acrylic acid (PP-AA), were prepared by a high energy irradiation method. The compatibilizing effect of newly prepared graft copolymers on immiscible PP/Nylon6 blends has been studied by means of UTM, SEM, and DSC techniques. The results indicate that PP-MAH and PP-St/MAH are more effective compatibilizers for PP/Nylon6 blends than PP-AA showing more than 30 % increase in impact strength, and the compatibilizing effect on PP/Nylon6 blends depends on molecular structure of the compatibilizers and the composition of the

  17. Objectives and functions of ionizing radiation metrology

    International Nuclear Information System (INIS)

    Rothe, H.

    1981-01-01

    Proceeding from the fundamental objectives of ionizing radiation metrology, the main tasks of metrological research and assurances of accurate measurements in dosimetry and activity determination are summarized. With a view to the technical performance of these tasks the state-of-the-art and the trends in reproduction and dissemination of dosimetric and activity units are outlined. Problems are derived that should be solved within the framework of the CMEA Standing Commissions on Standardization and on the Peaceful Uses of Atomic Energy. (author)

  18. Geiger-mueller radiation detector with means for detecting and indicating the existence of radiation overload

    International Nuclear Information System (INIS)

    Kovacs, T.; Mills, A.P.; Pfeiffer, L.N.

    1981-01-01

    When subjected to radiation overload existing geiger-mueller counters may give an erroneously low reading, resulting in possible hazard to personnel. The instant invention discloses simple and inexpensive apparatus to remedy this dangerous shortcoming. Depending on the geometry of the detector tube, two possible failure modes have been identified, and circuitry is disclosed to detect the existence of these respective failure modes. The disclosed apparatus indicates the absence of an overload condition, in addition to signaling, by both visible and audible means, the existence of excessive radiation that might result in erroneously low reading of the geiger-mueller counter

  19. Radiation sensitive devices and systems for detection of radioactive materials and related methods

    Science.gov (United States)

    Kotter, Dale K

    2014-12-02

    Radiation sensitive devices include a substrate comprising a radiation sensitive material and a plurality of resonance elements coupled to the substrate. Each resonance element is configured to resonate responsive to non-ionizing incident radiation. Systems for detecting radiation from a special nuclear material include a radiation sensitive device and a sensor located remotely from the radiation sensitive device and configured to measure an output signal from the radiation sensitive device. In such systems, the radiation sensitive device includes a radiation sensitive material and a plurality of resonance elements positioned on the radiation sensitive material. Methods for detecting a presence of a special nuclear material include positioning a radiation sensitive device in a location where special nuclear materials are to be detected and remotely interrogating the radiation sensitive device with a sensor.

  20. Radiation and detection of gravitational waves in laboratory conditions

    International Nuclear Information System (INIS)

    Bogolyubov, P.N.; Pisarev, A.F.; Shavokhina, N.S.

    1981-01-01

    Two variants are proposed and analyzed for an experiment on radiation and detection of gravitational waves in laboratory conditions in the optical and superhigh frequency range (band). In the first variant the laser light is parametrically transformed to the gravitational wave in the optical-inhomogeneous medium. The gravitational flux produced is registered by the inverse parametric transformation of the gravitational to light wave. In the second variant the radiation of gravitational waves is realized through hypersonic oscillations in piezocrystals, and the reception of waves is made by the superconducting coaxial resonator in which the gravitational wave resonantly transforms into the electromag= . netic wave. The analysis performed testifies to the possibility of an experiment of this type at the present time [ru

  1. Principles of radiation interaction in matter and detection

    CERN Document Server

    Leroy, Claude

    2016-01-01

    The fourth edition of this book has been widely revised. It includes additional chapters and some sections are complemented with either new ones or an extension of their content. In this latest edition a complete treatment of the physics and properties of semiconductors is presented, covering transport phenomena in semiconductors, scattering mechanisms, radiation effects and displacement damages. Furthermore, this edition presents a comprehensive treatment of the Coulomb scattering on screened nuclear potentials resulting from electrons, protons, light- and heavy-ions — ranging from (very) low up to ultra-relativistic kinetic energies — and allowing one to derive the corresponding NIEL (non-ionizing energy-loss) doses deposited in any material. The contents are organized into two parts: Chapters 1 to 7 cover Particle Interactions and Displacement Damage while the remaining chapters focus on Radiation Environments and Particle Detection. This book can serve as reference for graduate students and final-y...

  2. Child-bearing function in women with ionizing radiation

    International Nuclear Information System (INIS)

    Vusik, I.M.; Kogan, I.A.

    1979-01-01

    Study on a generating function in 393 women working in the sphere of ionizing radiation effect has shown that when working without exceeding the permissible irradiation level of 5 rem/year, some strengthening of this function is observed while working, with a considerable excess of permissible irradiation doses at the reproductive age, the decrease of childbirth and the increase in the number of miscarriages and premature birth are noted. The growth of girl childbirth as compared with boy childbirth is proportional to radiation load during the work with radiation sources. The secondary sterility appears in the same number of women exposed to the occupational irradiation and women of a control group

  3. Track structure theory in radiobiology and in radiation detection

    International Nuclear Information System (INIS)

    Katz, R.

    1978-01-01

    The response of biological cells, and many physical radiation and track detectors to ionizing radiations and to energetic heavily ionizing particles, results from the secondary and higher generation electrons ejected from the atoms and molecules of the detector by the incident primary radiation. The theory uses a calculation of the radial distribution of local dose deposited by secondary electrons (delta-rays) from an energetic heavy ion as a transfer function, relating the dose-response relation measured (or postulated) for a particular detector in a uniform radiation field (gamma-rays) to obtain the radial distribution in response about the ion's path, and thus the structure of the track of a particle. Subsequent calculations yield the response of the detector to radiation fields of arbitrary quality. The models which have been used for detector response arise from target theory, and are of the form of statistical models called multi-hit or multi-target detectors, in which it is assumed that there are sensitive elements (emulsion grains, or biological cell nuclei) which may require many hits (emulsion grains) or single hits in different targets (say, cellular chromosomes) in order to produce the observed end-point. Recent work has demonstrated that many-hit physical detectors do exist. From both emulsion sensitometry and from the structure of tracks of heavy ions, it can be shown that emulsion-developer combinations exist which yield many-hit response. There is also some evidence that the supralinearity in thermoluminescent dosimeters arises from a mixture of 1-hit and 2-hit response, perhaps of different trap structures within the same TLD crystal. These detectors can be expected to mimic the response of biological cells to radiations of different quality. Their patterns of response may help us to understand better the structure of particle tracks in SSNTD's. (author)

  4. Development of functional foods for radiation workers

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Sung Kee; Yu, Young Beob; Park, Hae Ran; Byun, Myung Woo; Yang, Jae Seung; Kim, Sung Ho; Yee, Sung Tae

    2000-03-01

    In searching modulators of immunity and hematopoiesis among natural products, being used as foods, six herbs exhibited lymphocyte proliferation in vitro, and six exhibited augmentation of hematopoietic cell growth. The combined treatments showed synergistic effects of lymphocyte proliferation and of hematopoietic cell growth. On the other hand, we found four effective oriental medicinal prescriptions, used as energy tonic or blood-building decoctions, for survival and regeneration of hematopoietic cells and for protection of stem cells of intestinal crypt in irradiated mice. On the basis of these results, extracts from combinations of herbs were made in expectation of higher effects in the three respects. In immuno modulation activity by the two combinations of herbs was confirmed in mice. In culture of bone narrow cells, growth improvement of non-adherent precursor and induction of cytokine expression by herb mixture extracts were observed. In evaluation of fractions, polysaccharide fraction showed modulation of immunity and hematopoiesis, and methanol fraction showed stem cell protection from radiation. On the basis of the results, we made two provisional products by addition of polysaccharide fraction to the water extract. In further research, the active components would be identified and the fractional foods would be developed for overcoming of declined immunity and radiation damage. For security of sanitation by irradiation, the stability in activity of irradiated resources was confirmed. (author)

  5. Detection of electromagnetic radiation using micromechanical multiple quantum wells structures

    Science.gov (United States)

    Datskos, Panagiotis G [Knoxville, TN; Rajic, Slobodan [Knoxville, TN; Datskou, Irene [Knoxville, TN

    2007-07-17

    An apparatus and method for detecting electromagnetic radiation employs a deflectable micromechanical apparatus incorporating multiple quantum wells structures. When photons strike the quantum-well structure, physical stresses are created within the sensor, similar to a "bimetallic effect." The stresses cause the sensor to bend. The extent of deflection of the sensor can be measured through any of a variety of conventional means to provide a measurement of the photons striking the sensor. A large number of such sensors can be arranged in a two-dimensional array to provide imaging capability.

  6. Improvements in or relating to radiation detection arrangements

    International Nuclear Information System (INIS)

    Davis, G.P.

    1977-01-01

    A radiation detection arrangement is described that that comprises a number of scintillator devices, and a single multi-channel photomultiplier tube. Light from the scintillator devices is incident on the photocathode through an entrance window in the tube and multiplier entrance separating means are provided whereby light from each of the devices is made to be incident upon the channel entrances of photomultiplier tube. Various geometrical forms for the scintillator devices are described. This arrangement avoids the use of large number of small photomultiplier tubes, which is expensive and gives rise to difficulties in stacking the tubes in closely spaced side-by-side relationship. (U.K.)

  7. Ticor-based scintillation detectors for detection of mixed radiation

    CERN Document Server

    Litvinov, L A; Kolner, V B; Ryzhikov, V D; Volkov, V G; Tarasov, V A; Zelenskaya, O V

    2002-01-01

    Detection of mixed radiation of thermal neutrons and gamma-rays have been realized using a new ceramic material based on small-crystalline long-wave scintillator alpha-Al sub 2 O sub 3 :Ti (Ticor) and lithium fluoride. Characteristics are presented for scintillators with Si-PIN-PD type photoreceivers and PMT under sup 2 sup 3 sup 9 Pu alpha-particles, sup 2 sup 0 sup 7 Bi internal conversion electrons,as well as sup 2 sup 4 sup 1 Am and sup 1 sup 3 sup 7 Cs gamma-quanta. Detection efficiency of thermal neutron is estimated for composite materials based on Ticor and lithium fluoride.

  8. Experiments performed with a functional model based on statistical discrimination in mixed nuclear radiation field

    International Nuclear Information System (INIS)

    Valcov, N.; Celarel, A.; Purghel, L.

    1999-01-01

    By using the statistical discrimination technique, the components of on ionization current, due to a mixed radiation field, may be simultaneously measured. A functional model, including a serially manufactured gamma-ray ratemeter was developed, as an intermediate step in the design of specialised nuclear instrumentation, in order to check the concept of statistical discrimination method. The obtained results are in good agreement with the estimations of the statistical discrimination method. The main characteristics of the functional model are the following: - dynamic range of measurement: >300: l; - simultaneous measurement of natural radiation background and gamma-ray fields; - accuracy (for equal exposure rates from gamma's and natural radiation background): 17%, for both radiation fields; - minimum detectable exposure rate: 2μR/h. (authors)

  9. Optimal Background Attenuation for Fielded Radiation Detection Systems

    International Nuclear Information System (INIS)

    Robinson, Sean M.; Kaye, William R.; Schweppe, John E.; Siciliano, Edward R.

    2006-01-01

    Radiation detectors are often placed in positions difficult to shield from the effects of terrestrial background. This is particularly true in the case of Radiation Portal Monitor (RPM) systems, as their wide viewing angle and outdoor installations make them susceptible to terrestrial background from the surrounding area. A low background is desired in most cases, especially when the background noise is of comparable strength to the signal of interest. The problem of shielding a generalized RPM from terrestrial background is considered. Various detector and shielding scenarios are modeled with the Monte-Carlo N Particle (MCNP) computer code. Amounts of nominal-density shielding needed to attenuate the terrestrial background to varying degrees are given, along with optimal shielding geometry to be used in areas where natural shielding is limited, and where radiation detection must occur in the presence of natural background. Common shielding solutions such as steel plating are evaluated based on the signal to noise ratio and the benefits are weighed against the incremental cost.

  10. Detection of gamma-neutron radiation by solid-state scintillation detectors. Detection of gamma-neutron radiation by novel solid-state scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ryzhikov, V.; Grinyov, B.; Piven, L.; Onyshchenko, G.; Sidletskiy, O. [Institute for Scintillation Materials of the NAS of Ukraine, Kharkov, (Ukraine); Naydenov, S. [Institute for Single Crystals of the National Academy of Sciences of Ukraine, Kharkov, (Ukraine); Pochet, T. [DETEC-Europe, Vannes (France); Smith, C. [Naval Postgraduate School, Monterey, CA (United States)

    2015-07-01

    It is known that solid-state scintillators can be used for detection of both gamma radiation and neutron flux. In the past, neutron detection efficiencies of such solid-state scintillators did not exceed 5-7%. At the same time it is known that the detection efficiency of the gamma-neutron radiation characteristic of nuclear fissionable materials is by an order of magnitude higher than the efficiency of detection of neutron fluxes alone. Thus, an important objective is the creation of detection systems that are both highly efficient in gamma-neutron detection and also capable of exhibiting high gamma suppression for use in the role of detection of neutron radiation. In this work, we present the results of our experimental and theoretical studies on the detection efficiency of fast neutrons from a {sup 239}Pu-Be source by the heavy oxide scintillators BGO, GSO, CWO and ZWO, as well as ZnSe(Te, O). The most probable mechanism of fast neutron interaction with nuclei of heavy oxide scintillators is the inelastic scattering (n, n'γ) reaction. In our work, fast neutron detection efficiencies were determined by the method of internal counting of gamma-quanta that emerge in the scintillator from (n, n''γ) reactions on scintillator nuclei with the resulting gamma energies of ∼20-300 keV. The measured efficiency of neutron detection for the scintillation crystals we considered was ∼40-50 %. The present work included a detailed analysis of detection efficiency as a function of detector and area of the working surface, as well as a search for new ways to create larger-sized detectors of lower cost. As a result of our studies, we have found an unusual dependence of fast neutron detection efficiency upon thickness of the oxide scintillators. An explanation for this anomaly may involve the competition of two factors that accompany inelastic scattering on the heavy atomic nuclei. The transformation of the energy spectrum of neutrons involved in the (n, n

  11. Ionizing radiation detection meter systems usability evaluation. Technical memorandum

    International Nuclear Information System (INIS)

    Severs, Y.; Hughes, R.; Tack, D.; Bossi, L.L.M.

    2002-12-01

    In support of the Canadian Forces Nuclear Detection, Identification and Dosimetry project a usability trial of three Ionizing Radiation Detection Meter Systems (IRDMS) was conducted 18-22 June 2001 at Connaught Ranges. The systems evaluated: System 1: ANPDR 77 Operational System with PDR 77 Alpha/Beta probes and GPS (Global Positioning System) Training System; System 2: ADM 300C Operational System with ABP 100 Alpha/Beta probes and GPS Training System, and System 3: RAM R200 Operational System with PA 100M and RG12 Alpha/Beta probes and GPS Training System. Twelve military personnel (Private to Captain) determined compliance with the bid evaluation criteria. The counter-balanced study, based on a Latin square design, was divided into two assessment phases, an operational phase and a training system phase, which rotated three groups (of four participants each) concurrently through each IRDMS. Groups were trained in set-up, maintenance and operation of each bid IRDMS prior to evaluation. The operational evaluation consisted of a test/maintenance stand, an indoor/outdoor operational stand, and an indoor,/outdoor training system stand. Participants rated the utility and usability of each system, by measuring case of use/maintenance under a range of relevant operational and clothing conditions, compatibility with soldier tasks, compatibility with clothing, compatibility with equipment and operational environments, and case of learning (including an assessment of initial and refresher training implications). A 7-point Likert-like acceptability rating scale, which covered a range from completely unacceptable (1) to completely acceptable (7), was used to evaluate the measures. The combined weighted mean scores were 584.3 for System 1 (70 o /b), 682.0 for System 2 (81 %) and 756.9 for System 3 (90%) out of a total possible score of 840. Participants reported mean scores for System 1 between barely unacceptable and borderline for both indoor and outdoor operations. System 2

  12. Application of functional polymers synthesized by radiation

    International Nuclear Information System (INIS)

    Yoshii, Fumio

    2005-01-01

    It was found that polysaccharide derivatives undergo crosslinking under ionization irradiation at high concentration - so called 'paste-like' conditions. The crosslinking behavior of carboxymethylcellulose (CMC) was largely affected by concentration and degree of substitution (DS). The concentration of 20-30% for DS 1.3 and 50 - 60% for DS 2.2 were the most effective for crosslinking of CMC. Bedsore prevention mat filled up with CMC soft hydrogel crosslinked by irradiation at a paste-like condition was applied as a health care product. It was conformed that CMC dry gel is effective as an absorber of water, even up to 60-70% in order to carry out fermentation effectively of original excrement from livestock, which include 90% of water. Polylactic acid (PLA) irradiated in the presence of polyfunctional monomer (PFM), triallyisocyanurate (TAIC) results in crosslinking. The crosslinked PLA possesses such properties as biodegradability, transparency, high heat-stability and it can be use as heat-shrinkable tubes. Radiation crosslinked poly (vinyl alcohol) hydrogel was applied as wound healing dressing material and it was commercialized since July 2004. (author)

  13. Radiosensitivity of yeast cells as a function of radiation LET

    International Nuclear Information System (INIS)

    Lobachevskij, P.N.; Krasavin, E.A.

    1988-01-01

    A model is proposed for interpreting the radiosensitivity of yeast cells as a function of linear energy transfer (LET) of ionizing radiation. The model takes into account the role of repair processes in sensitivity of yeast cells to ionizing radiation of different LET. Two types of repair are discussed: (1) a nonspecific repair (characteristic of both haploid and diploid cells), and (2) a diploid - soecific repair (characteristic of diploid cells only)

  14. Radiation transmission type pipe wall thinning detection device and measuring instruments utilizing ionizing radiation

    International Nuclear Information System (INIS)

    Higashi, Yasuhiko

    2009-01-01

    We developed the device to detect thinning of pipe thorough heat insulation in Power Plant, etc, even while the plant is under operation. It is necessary to test many parts of many pipes for pipe wall thinning management, but it is difficult within a limited time of the routine test. This device consists of detector and radiation source, which can detect the pipe (less than 500 mm in external diameter, less than 50 mm in thickness) with 1.6%-reproducibility (in a few-minutes measurement), based on the attenuation rate. Operation is easy and effective without removing the heat insulation. We will expand this thinning detection system, and contribute the safety of the Plant. (author)

  15. Accurate and efficient computation of synchrotron radiation functions

    International Nuclear Information System (INIS)

    MacLeod, Allan J.

    2000-01-01

    We consider the computation of three functions which appear in the theory of synchrotron radiation. These are F(x)=x∫x∞K 5/3 (y) dy))F p (x)=xK 2/3 (x) and G p (x)=x 1/3 K 1/3 (x), where K ν denotes a modified Bessel function. Chebyshev series coefficients are given which enable the functions to be computed with an accuracy of up to 15 sig. figures

  16. Piezoelectric Materials Under Natural and Man-Made Radiation: The Potential for Direct Radiation Detection

    Science.gov (United States)

    Wart, Megan; Simpson, Evan; Flaska, Marek

    2018-01-01

    Radiation detection systems used for monitoring long term waste storage need to be compact, rugged, and have low or no power requirements. By using piezoelectric materials it may be possible to create a reliable self-powered radiation detection system. To determine the feasibility of this approach, the electrical signal response of the piezoelectric materials to radiation must be characterized. To do so, an experimental geometry has been designed and a neutron source has been chosen as described in this paper, which will be used to irradiate a uranium foil for producing fission fragments. These future experiments will be aimed at finding the threshold of exposure of lead zirconate titanate (PZT) plates needed to produce and electrical signal. Based on the proposed experimental geometry the thermal neutron beam-line at the Breazeale Reactor at The Pennsylvania State University will be used as the neutron source. The uranium foil and neutron source will be able to supply a maximum flux of 1.5e5 fission fragments/second*cm2 to each of the PZT plates.

  17. Piezoelectric Materials Under Natural and Man-Made Radiation: The Potential for Direct Radiation Detection

    Directory of Open Access Journals (Sweden)

    Wart Megan

    2018-01-01

    Full Text Available Radiation detection systems used for monitoring long term waste storage need to be compact, rugged, and have low or no power requirements. By using piezoelectric materials it may be possible to create a reliable self-powered radiation detection system. To determine the feasibility of this approach, the electrical signal response of the piezoelectric materials to radiation must be characterized. To do so, an experimental geometry has been designed and a neutron source has been chosen as described in this paper, which will be used to irradiate a uranium foil for producing fission fragments. These future experiments will be aimed at finding the threshold of exposure of lead zirconate titanate (PZT plates needed to produce and electrical signal. Based on the proposed experimental geometry the thermal neutron beam-line at the Breazeale Reactor at The Pennsylvania State University will be used as the neutron source. The uranium foil and neutron source will be able to supply a maximum flux of 1.5e5 fission fragments/second*cm2 to each of the PZT plates.

  18. Biochemical and Radiobiological Factors in the Early Detection of Radiation Injury in Mammals

    Energy Technology Data Exchange (ETDEWEB)

    Cole, L. J. [Life Sciences Division, Stanford Research Institute, Menlo Park, CA (United States)

    1971-03-15

    In considering the body of radiobiological knowledge upon which the present possibilities for the development of an objective quantitative laboratory procedure for early detection of radiation injury depend, it is evident that there are at least three general categories of radiation effects which are relevant to this objective: (1) Products of the enzymatic-chemical breakdown of macromolecules, and lysis of killed or dying cells from radiosensitive tissues, for example deoxypolynucleotides from lymphoid tissues and bone marrow; (2) Radiation-induced inhibition of synthesis of deoxyribonucleic acid (DNA) and/or other macromolecules, eliciting alterations in tissue and blood concentrations and pool size of metabolic intermediates in the synthesis, for example, deoxycytidine; (3) Radiation-induced alterations, suppression, or cessation of specialized cell function; of particular interest here is the immunological functions of lymphocytes, including those in the circulating blood. For rodents, the exquisite radiosensitivity of bone-marrow-stem cells as well as of lymphocytes has been precisely measured by modern cellular radiobiological techniques: the colony-forming technique of Till and McCulloch, yielding a D{sub 0} for bone-marrow cells of about 80 R; and the graft-versus-host reactivity of transplanted lymphocytes yielding a similar D{sub 0} value. In our own hands, a modified colony-formation technique for dog bone-marrow cells irradiated in.vitro and in vivo give D{sub 0} values of {approx}100 R. Thus, on the basis of radiation sensitivity and the time-relationships for interphase cell death for lymphocytes, it appears that this cell class is probably the best ''candidate'' source for an early radiation-injury detection system. However,- the important report by Zicha and Buric indicates that extrapolation of biochemical data on radiation dosimetry from rodents to man is not necessarily feasible, at least in the. case of the urinary excretion of deoxycytidine

  19. Radiation anomaly detection algorithms for field-acquired gamma energy spectra

    Science.gov (United States)

    Mukhopadhyay, Sanjoy; Maurer, Richard; Wolff, Ron; Guss, Paul; Mitchell, Stephen

    2015-08-01

    The Remote Sensing Laboratory (RSL) is developing a tactical, networked radiation detection system that will be agile, reconfigurable, and capable of rapid threat assessment with high degree of fidelity and certainty. Our design is driven by the needs of users such as law enforcement personnel who must make decisions by evaluating threat signatures in urban settings. The most efficient tool available to identify the nature of the threat object is real-time gamma spectroscopic analysis, as it is fast and has a very low probability of producing false positive alarm conditions. Urban radiological searches are inherently challenged by the rapid and large spatial variation of background gamma radiation, the presence of benign radioactive materials in terms of the normally occurring radioactive materials (NORM), and shielded and/or masked threat sources. Multiple spectral anomaly detection algorithms have been developed by national laboratories and commercial vendors. For example, the Gamma Detector Response and Analysis Software (GADRAS) a one-dimensional deterministic radiation transport software capable of calculating gamma ray spectra using physics-based detector response functions was developed at Sandia National Laboratories. The nuisance-rejection spectral comparison ratio anomaly detection algorithm (or NSCRAD), developed at Pacific Northwest National Laboratory, uses spectral comparison ratios to detect deviation from benign medical and NORM radiation source and can work in spite of strong presence of NORM and or medical sources. RSL has developed its own wavelet-based gamma energy spectral anomaly detection algorithm called WAVRAD. Test results and relative merits of these different algorithms will be discussed and demonstrated.

  20. Ionizing radiation-induced DNA injury and damage detection in patients with breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Borrego-Soto, Gissela; Ortiz-Lopez, Rocio; Rojas-Martinez, Augusto, E-mail: arojasmtz@gmail.com, E-mail: augusto.rojasm@uanl.mx [Departamento de Bioquímica y Medicina Molecular, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, Nuevo León (Mexico)

    2015-10-15

    Breast cancer is the most common malignancy in women. Radiotherapy is frequently used in patients with breast cancer, but some patients may be more susceptible to ionizing radiation, and increased exposure to radiation sources may be associated to radiation adverse events. This susceptibility may be related to deficiencies in DNA repair mechanisms that are activated after cell-radiation, which causes DNA damage, particularly DNA double strand breaks. Some of these genetic susceptibilities in DNA-repair mechanisms are implicated in the etiology of hereditary breast/ovarian cancer (pathologic mutations in the BRCA 1 and 2 genes), but other less penetrant variants in genes involved in sporadic breast cancer have been described. These same genetic susceptibilities may be involved in negative radiotherapeutic outcomes. For these reasons, it is necessary to implement methods for detecting patients who are susceptible to radiotherapy-related adverse events. This review discusses mechanisms of DNA damage and repair, genes related to these functions, and the diagnosis methods designed and under research for detection of breast cancer patients with increased radiosensitivity. (author)

  1. In-Situ Radiation Detection Demonstration Final Report

    International Nuclear Information System (INIS)

    Mohagheghi, Amir H.; Reese, Robert; Miller, David R.; Miller, Mark Laverne; Duce, Stephen

    2000-01-01

    The Department of Defense (DoD) has hundreds of facilities where radioactive materials have been used or are being used, including firing ranges, low-level radioactive waste disposal areas, and areas where past activities have resulted in environmental contamination. Affected sites range in size from a few acres to square miles. Impact to the DoD comes through military base closure and release to the public. It is important that radioactive contaminants are remediated to levels that result in acceptable risk to the public. Remediation requires characterization studies, e.g., sampling and surveys, to define the affected areas, removal actions, and final confirmatory sampling and surveys. Characterization of surface contamination concentrations has historically been performed using extensive soil sampling programs in conjunction with surface radiation surveys conducted with hand-held radiation monitoring equipment. Sampling is required within the suspect affected area and a large buffer area. Surface soil contaminant characterization using soil sampling and hand held monitoring are costly, time consuming, and result in long delays between submission of samples for analysis and obtaining of final results. This project took an existing, proven radiation survey technology that has had limited exposure and improved its capabilities by documenting correlation factors for various detector/radionuclide geometries that commonly occur in field surveys. With this tool, one can perform characterization and final release surveys much more quickly than is currently possible, and have detection limits that are as good as or better than current technology. This paper will discuss the capabilities of a large area plastic scintillation detector used in conjunction with a global positioning system (GPS) to improve site characterization, remediation, and final clearance surveys of the radioactively contaminated site. Survey results can rapidly identify areas that require remediation as

  2. Drone Detects Hotspots of Radiation and CO2 Outgassing

    Science.gov (United States)

    Takac, M.; Kletetschka, G.

    2016-12-01

    Market availability of environmental sensors and drones allow drones to become part of the education activities promoting environmental science both in high schools and grade schools. Here we provide one mode of drone operation for potential use in educational framework.Drone can carry devices that are capable of measuring various parameters of the environment. Commercial radiation and gas (CO2) sensors can be attached to the commercial drone. Our specific drone acquired data set of CO2 measurements over the natural outgassing of CO2 and another set of measurements over old uranium mine. Measurements of CO2 gave a poor signal to noise ratio. Its sensitivity, however, was enough to detect an increase in CO2 in the closed room with humans present compared to the fresh air outside. We could measure an increase of CO2 when directly over the source of natural CO2 outburst. Our data showed that CO2 concentration quickly dilutes in air few meters from the source to concentrations that are within the noise limit. However, the radiation measurements provided a map that correlates well with radiation survey obtained by ground measurements with more sophisticated instrument. We used the most common conventional drone, which is on the market and highly effective personal dosimeter, which can also be used for fire and rescue for its durability. Experimental field measurements were done at Třebsko site, where a map of radioactivity using standard spot measurements was already done. A field experiment was done in winter months when demand for the drone was higher due to cold and wet weather. We tested profiles and height versus the intensity of the recorded signal measurements. We consulted our results and ability to measure radioactivity with the regional fire-fighting units headquarters and verify the applicability and use of this technology for their needs.

  3. Energy nonlinearity in radiation detection materials: Causes and consequences

    International Nuclear Information System (INIS)

    Jaffe, J.E.; Jordan, D.V.; Peurrung, A.J.

    2007-01-01

    The phenomenology and present theoretical understanding of energy nonlinearity (nonproportionality) in radiation detection materials is reviewed, with emphasis on gamma-ray spectroscopy. Scintillators display varying degrees and patterns of nonlinearity, while semiconductor detectors are extremely linear, and gas detectors show a characteristic form of nonproportionality associated with core levels. The relation between nonlinear response (to both primary particles and secondary electrons) and spectrometer resolution is also discussed. We review the qualitative ideas about the origin of nonlinearity in scintillators that have been proposed to date, with emphasis on transport and recombination of electronic excitations. Recent computational and experimental work on the basic physics of scintillators is leading towards a better understanding of energy nonlinearity and should result in new, more linear scintillator materials in the near future

  4. Present status of fuel motion detection by radiation

    International Nuclear Information System (INIS)

    Sumita, Kenji; Mizuta, Hiroshi; Ishizuka, Makoto; Ara, Katsuyuki; Nakata, Hirokatsu.

    1978-05-01

    In reactor safety research, it is important to know transient fuel behavior under accidental conditions. Transient histories such as temperature and axial expansion of fuel and cladding and internal pressure of fuel rod are thus measured in experiments simulating accidents. If fuel motion could then be observed during and after fuel failure, this would greatly make for fuel behavior research. The present status is reviewed of fuel motion detections by radiations such as neutron, γ-ray and X-ray, including the principle and system. A neutron hodoscope among them is used already with practical results in in-reactor safety experiments of sodium-cooled fast breeder reactor. So, this is described in detail and its conceptual design as applied to the NSRR is presented. (auth.)

  5. Nuclear radiation detected optical pumping of neutron deficient Hg isotopes

    International Nuclear Information System (INIS)

    Bonn, J.

    1975-01-01

    The extension of the Nuclear Radiation Detected Optical Pumping method to mass-separated samples of isotopes far off stability is presented for a series of light Hg isotopes produced at the ISOLDE facility at CERN. The isotope under investigation is transferred by an automatic transfer system into the optical pumping apparatus. Zeeman scanning of an isotopically pure Hg spectral lamp is used to reach energetic coincidence with the hyperfine structure components of the 6s 2 1 S 0 -6s6p 3 P 1 (lambda = 2537 A) resonance line of the investigated isotope and the Hg lamp. The orientation build up by optical pumping is monitored via the asymmetry or anisotropy of the nuclear radiation. Nuclear spins, magnetic moments, electric quadrupole moments and isotopic shift are obtained for 181 Hg- 191 Hg using the β-asymmetry as detector. The extension of the method using the γ-anisotropy is discussed and measurements on 193 Hg are presented. (orig./HK)

  6. IAEA eLearning Program: The Use of Radiation Detection Instruments

    International Nuclear Information System (INIS)

    2010-01-01

    This CD-ROM contains a computer based training on Radiation Detection Techniques for Nuclear Security Applications. The IAEA Nuclear Security eLearning tool offers computer based training to Frontline Officers to improve their understanding about key elements of the use of radiation detection instruments. The eLearning program prepares Frontline Officers for the IAEA Detection and Response Frontline Officer course

  7. Micronuclei: sensitivity for the detection of radiation induced damage

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Nasazzi, N.B.; Taja, M.R.

    1998-01-01

    The in vitro cytokinesis-block (CB) micronucleus (MN) assay for human peripheral blood has been used extensively for the assessment of chromosomal damage induced by ionizing radiation and chemicals and considered a suitable biological dosimeter for estimating in vivo whole body exposures, particularly in the case of large scale radiation accidents. One of the major drawbacks of the MN assay is its reduced sensitivity for the detection of damage induced by low doses of low LET radiation, due to the high variability among the spontaneous MN frequencies. It is suggested that age, smoking habit and sex are the main confounding factors that contribute to the observed variability. Previous work in our laboratory, shows a significant positive correlation of the spontaneous and radiation induced MN frequencies with age and smoking habit, the latter being the strongest confounder. These findings led to in vitro studies of the dose-response relationships for smoking and non smoking donors evaluated separately, using 60 Co γ rays. The objectives of the present work are: 1-To increase the amount of data of the dose-response relationships, using γ rays from a 60 Co source, for smoking and non smoking donors, in order to find, if applicable, a correction factor for the calibration curve that takes into account the smoking habit of the individual in the case of accidental overexposure dose assessment, particularly in the low dose range. 2-To establish general conclusions on the current state of the technique. The sample for smoking and non smoking calibration curves was enlarged in the range of 0Gy to 2Gy. The fitting of both curves, performed up to the 2Gy dose, resulted in a linear quadratic model. MN distribution among bi nucleated cells was found to be over dispersed with respect to Poisson distribution, the average ratio of variance to mean being 1.13 for non smokers and 1.17 for smokers. Each fitted calibration curve, for smoking and non smoking donors, fell within the 95

  8. Detecting Differential Person Functioning in Emotional Intelligence

    Science.gov (United States)

    Alsmadi, Yahia M.; Alsmadi, Abdalla A.

    2009-01-01

    Differential Item Functioning (DIF) is a widely used term in test development literature. It is very important to analyze test's data for DIF because It is a serious threat to validity. If the same data matrix was transposed, similar analysis can be carried for Differential Person Functioning (DPF). The purpose of this paper is to introduce and…

  9. Effect of ionizing radiation on platelet function in vitro

    International Nuclear Information System (INIS)

    Kalovidouris, A.E.; Papayannis, A.G.

    1981-01-01

    The effect of ionizing radiation on platelet function was investigated in vitro. Platelet-rich plasma (300x10 9 /l) was irradiated with doses of 1, 4, 10, 20 and 50 Gy. Platelet function tests were performed on both irradiated and control (non-irradiated) platelet samples. The platelet function tests were (1) platelet aggregation by ADP (1, 2, 4 μmol final concentration), adrenaline and collagen, (2) ADP-release from platelets, (3) clot retraction and (4) platelet factor-3 availability. It was found that roentgen irradiation of platelets in vitro did not affect these platelet function tests. (Auth.)

  10. Detecting reduced renal function in children

    DEFF Research Database (Denmark)

    Andersen, Trine Borup; Jødal, Lars; Erlandsen, Erland J

    2013-01-01

    Background The aim of this study was to compare the ability of renal indicators [serum creatinine (SCr), cystatin C (SCysC)] and glomerular filtration rate (GFR)-models to discriminate normal and reduced renal function. As a single cut-off level will always lead to false classifications, we propose...... function was defined as a GFR ofcreatinine (SCr-ratio), and eight published GFR-models were compared for their ability to correctly classify renal function as normal or reduced. Cut-off levels were determined so as to give 99 % certainty outside the gray zone...

  11. Design of autotrack detecting instrument for solar UV radiation

    Science.gov (United States)

    Xia, Jiangtao; Mao, Xiaoli; Zhao, Jing

    2009-11-01

    In order to autotrack the object and detect the solar UV index, a reliable real-time high-precise instrument is proposed in this paper. This instrument involves two subsystems: the autotrack and detecting modules. The autotrack module consists of four-quadrant photo detector, multi-channel signal processing circuit and precise stepping system. The detecting module designed for dada measurement and acquisition is made up of the ultraviolet sensor UV460 and high precision A/D converter MAX1162. The key component of the entire instrument is ultralow-power microprocessor MSP430 which is used for entire system controlling and data processing. The lower system of autotracking and measurement is communicated with upper PC computer by RS232 module. In the experiment, the tracking precision of two-dimensional motion revolving stage is calibrated to be less than 0.05°. Experimental results indicate that the system designed could realize the precise autotracking and detecting function well, and the measure precision of system has reached the desirable target.

  12. Fault detection using parameter transfer functions

    Energy Technology Data Exchange (ETDEWEB)

    Salamun, I; Mavko, B; Stritar, A [University of Ljubljana, Josef Stefan Inst., Ljubljana (Slovenia). Reactor Engineering Div.

    1997-12-31

    To reduce the number of alarms in NPP many techniques have been proposed for process monitoring and diagnosis. The object of our investigation is a dynamic process with digital signals. The general parametric model defines the transfer function form and it covers all dynamics characteristics between two monitoring parameters. To determine the proper model coefficients we are using recoursing least square methods. The transfer function coefficients define the correlation between two variables in desired time period. During process monitoring just the relation is observed because the number of coefficients and the structure is predefined with transfer function form. During plant operation the transfer functions for important parameters must be calculated and estimated. The estimated values are input parameters for an analytical algorithm. It determines which part of system causes the transient and recognizes it. The proposed methodology allows a computer to monitor the system behaviour and to find out the most probable cause for abnormal condition. (author). 3 refs, 5 figs, 2 tabs.

  13. Fault detection using parameter transfer functions

    International Nuclear Information System (INIS)

    Salamun, I.; Mavko, B.; Stritar, A.

    1996-01-01

    To reduce the number of alarms in NPP many techniques have been proposed for process monitoring and diagnosis. The object of our investigation is a dynamic process with digital signals. The general parametric model defines the transfer function form and it covers all dynamics characteristics between two monitoring parameters. To determine the proper model coefficients we are using recoursing least square methods. The transfer function coefficients define the correlation between two variables in desired time period. During process monitoring just the relation is observed because the number of coefficients and the structure is predefined with transfer function form. During plant operation the transfer functions for important parameters must be calculated and estimated. The estimated values are input parameters for an analytical algorithm. It determines which part of system causes the transient and recognizes it. The proposed methodology allows a computer to monitor the system behaviour and to find out the most probable cause for abnormal condition. (author). 3 refs, 5 figs, 2 tabs

  14. Development of radiation detection and measurement system - Development of scintillation radiation sensor

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hee Dong; Kim, Wan [Kyungpook National University, Taegu (Korea); Kim, Do Sung [Taegu University, Taegu (Korea)

    2000-03-01

    We have been fabricated CsI(Tl) scintillation crystals and plastic scintillators for radiation-based measuring equipment. CsI (Tl) single crystals doped with thallium as an activator were grown using the Czochralski method. The crystal structure of grown CsI(Tl) was bcc, and it was confirmed that its lattice constant was 4,568 A. The spectral range of luminescence of CsI(Tl) was 350 {approx} 700 nm independent of thallium concentration, and the fast component of the luminescence was decreased with increasing thallium concentration. The energy resolution of CsI(Tl) scintillator doped with 0.1 mole% thallium was about 9% for 137 Cs {gamma}-rays. The relation formula of {gamma}-ray energy versus energy resolution was ln(FWHM%)=-0.705ln({epsilon})+6.75. The radiation damage of CsI(Tl) increased in proportion to thallium concentration and radiation damage of CsI(Tl) increased in proportion to thallium concentration and radiation dosage, and the irradiated crystals were colored reddish. The radiation induced absorption bands appeared around 355, 425, 520 and 555 nm, and their energy level were about 3.50, 2.88, 2.39 and 2.21 eV. Plastic scintillators were fabricated thermal polymerization method. Those were polymerizing at 120 deg. C, during 72 hours, and annealing at 75 deg. C, during 24 hours. When the concentration of 1st solute was 1.5 wt% and concentration of 2nd solute was 0.01 wt%, the characteristics of scintillation were very excellent. Also 3.0 wt% tetraphenyl lead were loaded to improve the detection efficiency of {gamma}-ray. The range of emission spectrum was 400 {approx} 450nm, and the central peak was 415 nm. The radiation damage was not appear under 1*10{sup 3}Gy, but the color of plastic scintillator was changed to brown, over 1*10{sup 4}Gy exposured. 84 refs., 39 figs. (Author)

  15. DIF Trees: Using Classification Trees to Detect Differential Item Functioning

    Science.gov (United States)

    Vaughn, Brandon K.; Wang, Qiu

    2010-01-01

    A nonparametric tree classification procedure is used to detect differential item functioning for items that are dichotomously scored. Classification trees are shown to be an alternative procedure to detect differential item functioning other than the use of traditional Mantel-Haenszel and logistic regression analysis. A nonparametric…

  16. Role of electroweak radiation in predictions for dark matter indirect detection

    Energy Technology Data Exchange (ETDEWEB)

    Ali Cavasonza, Leila; Pellen, Mathieu; Kraemer, Michael [RWTH Aachen, Aachen (Germany)

    2015-07-01

    A very exciting challenge in particle and astroparticle physics is the exploration of the nature of dark matter. The evidences of the existence of dark matter are also the strongest phenomenological indications for physics beyond the Standard Model. A huge experimental effort is currently made at colliders and via astrophysical experiments to shed light on the nature of dark matter: dark matter may be produced at colliders or detected through direct and indirect detection experiments. The interplay and complementarity between these different approaches offers extraordinary opportunities to improve our understanding of the nature of dark matter or to set constraints on dark matter models. In indirect detection one searches for dark matter annihilation products, that produce secondary antimatter particles like positrons and antiprotons. Such antimatter particles propagate through the Galaxy and can be detected at Earth by astrophysical experiments. Particularly interesting is the importance of electroweak corrections to the predictions for the expected fluxes at Earth. The inclusion of EW radiation from the primary dark matter annihilation products can significantly affect the spectra of the secondary SM particles. The EW radiation can be described using fragmentation functions, as done for instance in QCD. We study the quality of this approximation in a simplified SUSY model and in a UED model.

  17. Asymmetric devices based on carbon nanotubes for terahertz-range radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, G. E., E-mail: gefedorov@mail.ru; Stepanova, T. S.; Gazaliev, A. Sh.; Gaiduchenko, I. A.; Kaurova, N. S.; Voronov, B. M.; Goltzman, G. N. [Moscow State Pedagogical University (Russian Federation)

    2016-12-15

    Various asymmetric detecting devices based on carbon nanotubes (CNTs) are studied. The asymmetry is understood as inhomogeneous properties along the conducting channel. In the first type of devices, an inhomogeneous morphology of the CNT grid is used. In the second type of devices, metals with highly varying work functions are used as the contact material. The relation between the sensitivity and detector configuration is analyzed. Based on the data obtained, approaches to the development of an efficient detector of terahertz radiation, based on carbon nanotubes are proposed.

  18. The Rapalogue, CCI-779, improves salivary gland function following radiation.

    Science.gov (United States)

    Morgan-Bathke, Maria; Harris, Zoey I; Arnett, Deborah G; Klein, Rob R; Burd, Randy; Ann, David K; Limesand, Kirsten H

    2014-01-01

    The standard of care for head and neck cancer typically includes surgical resection of the tumor followed by targeted head and neck radiation. However depending on tumor location and stage, some cases may not require surgical resection while others may be treated with chemoradiation. Unfortunately, these radiation treatments cause chronic negative side effects for patients. These side effects are associated with damage to surrounding normal salivary gland tissue and include xerostomia, changes in taste and malnutrition. The underlying mechanisms of chronic radiation-induced salivary gland dysfunction are unknown, however, in rodent models persistently elevated proliferation is correlated with reduced stimulated salivary flow. The rapalogue, CCI-779, has been used in other cell systems to induce autophagy and reduce proliferation, therefore the aim of this study was to determine if CCI-779 could be utilized to ameliorate chronic radiation-induced salivary gland dysfunction. Four to six week old Atg5f/f; Aqp5-Cre, Atg5+/+; Aqp5-Cre and FVB mice were treated with targeted head and neck radiation. FVB mice were treated with CCI-779, chloroquine, or DMSO post-radiation. Stimulated salivary flow rates were determined and parotid and submandibular salivary gland tissues were collected for analyses. Mice with a defect in autophagy, via a conditional knockout of Atg5 in the salivary glands, display increased compensatory proliferation in the acinar cell compartment and hypertrophy at 24-72 hours following radiation. FVB mice treated with post-therapy CCI-779 have significant improvements in salivary gland physiology as determined by stimulated salivary flow rates, proliferation indices and amylase production and secretion. Consequently, post-radiation use of CCI-779 allows for improvement of salivary gland function and reestablishment of glandular homeostasis. As CCI-779 is already FDA approved for other uses, it could have a secondary use to alleviate the chronic side

  19. The Rapalogue, CCI-779, improves salivary gland function following radiation.

    Directory of Open Access Journals (Sweden)

    Maria Morgan-Bathke

    Full Text Available The standard of care for head and neck cancer typically includes surgical resection of the tumor followed by targeted head and neck radiation. However depending on tumor location and stage, some cases may not require surgical resection while others may be treated with chemoradiation. Unfortunately, these radiation treatments cause chronic negative side effects for patients. These side effects are associated with damage to surrounding normal salivary gland tissue and include xerostomia, changes in taste and malnutrition. The underlying mechanisms of chronic radiation-induced salivary gland dysfunction are unknown, however, in rodent models persistently elevated proliferation is correlated with reduced stimulated salivary flow. The rapalogue, CCI-779, has been used in other cell systems to induce autophagy and reduce proliferation, therefore the aim of this study was to determine if CCI-779 could be utilized to ameliorate chronic radiation-induced salivary gland dysfunction. Four to six week old Atg5f/f; Aqp5-Cre, Atg5+/+; Aqp5-Cre and FVB mice were treated with targeted head and neck radiation. FVB mice were treated with CCI-779, chloroquine, or DMSO post-radiation. Stimulated salivary flow rates were determined and parotid and submandibular salivary gland tissues were collected for analyses. Mice with a defect in autophagy, via a conditional knockout of Atg5 in the salivary glands, display increased compensatory proliferation in the acinar cell compartment and hypertrophy at 24-72 hours following radiation. FVB mice treated with post-therapy CCI-779 have significant improvements in salivary gland physiology as determined by stimulated salivary flow rates, proliferation indices and amylase production and secretion. Consequently, post-radiation use of CCI-779 allows for improvement of salivary gland function and reestablishment of glandular homeostasis. As CCI-779 is already FDA approved for other uses, it could have a secondary use to alleviate

  20. Thyroid and hypophysial function in radiation therapy of breast cancer

    International Nuclear Information System (INIS)

    Yakimova, T.P.; Lozinskaya, I.N.

    1984-01-01

    In breast cancer a decrease in triiodothyronine concentration was revealed with the normal level of thyroxine that may be associated with the disturbed peripharal metabolism into triiodothyronine. The lowering of thyroid functional activity is noted during radiation therapy of patients at menopause. Administration of thyroidin during radiation therapy to elderly patients with the 3 stage of the disease compensated for hormone deficiency producing a sparing effect on the thyroid, and influenced the therapeutic results favorably. A high level of the somatotropic hormone was observed in patients, of the reproductive age and at menopause, the level of insulin was increased in all the patients

  1. Control of Polymer Nanostructure and Functionality via Radiation Grafting

    International Nuclear Information System (INIS)

    Palmese, G.R.

    2006-01-01

    Radiation grafting provides a useful means for controlling polymer structure and performance. Particularly, it is appropriate for combining materials with distinct thermodynamic characteristics chemically at interfaces. Therefore polymeric materials that generally will not mix - i.e hydrophilic and hydrophobic polymers - can be combined efficiently using radiation based methods. This is of particular importance when attempting to form polymer-polymer nanocomposites where the thermodynamic penalty associated with high specific interfacial surface area is very large. Generally, the combination at small scales of such distinct materials is appropriate when specific functionality is desired while maintaining structural performance characteristics. In such cases the hydrophilic polymer lends functional characteristics such as ionic conductivity, self-healing, and actuation, while the hydrophobic polymer component provides structural stability. In this communication a summary of our recent work concerning the use of radiation grafting for the synthesis of nanostructured functional materials is given. Examples to be discussed include toughing of polymeric systems, the synthesis polymeric and inorganic nanotubes, and the design of permeation selective membranes. These examples will be used to demonstrate the effectiveness of radiation grafting techniques for controlling polymer properties and small-scale structure

  2. Delay-Line Three-Dimensional Position Sensitive Radiation Detection

    Science.gov (United States)

    Jeong, Manhee

    High-resistivity silicon(Si) in large volumes and with good charge carrier transport properties has been produced and achieved success as a radiation detector material over the past few years due to its relatively low cost as well as the availability of well-established processing technologies. One application of that technology is in the fabrication of various position-sensing topologies from which the incident radiation's direction can be determined. We have succeeded in developing the modeling tools for investigating different position-sensing schemes and used those tools to examine both amplitude-based and time-based methods, an assessment that indicates that fine position-sensing can be achieved with simpler readout designs than are conventionally deployed. This realization can make ubiquitous and inexpensive deployment of special nuclear materials (SNM) detecting technology becomes more feasible because if one can deploy position-sensitive semiconductor detectors with only one or two contacts per side. For this purpose, we have described the delay-line radiation detector and its optimized fabrication. The semiconductor physics were simulated, the results from which guided the fabrication of the guard ring structure and the detector electrode, both of which included metal-field-plates. The measured improvement in the leakage current was confirmed with the fabricated devices, and the structures successfully suppressed soft-breakdown. We also demonstrated that fabricating an asymmetric strip-line structure successfully minimizing the pulse shaping and increases the distance through which one can propagate the information of the deposited charge distribution. With fabricated delay-line detectors we can acquire alpha spectra (Am-241) and gamma spectra (Ba-133, Co-57 and Cd-109). The delay-line detectors can therefore be used to extract the charge information from both ion and gamma-ray interactions. Furthermore, standard charge-sensitive circuits yield high SNR

  3. Study and characterization of III-V semiconductor materials for applications in ionizing radiation detection

    International Nuclear Information System (INIS)

    Moulin, H.

    1989-11-01

    The photoconduction in the bulk of the gallium arsenide (GaAs) and of the indium phosphide doped with iron (InP:Fe) is investigated. These semiconductor materials are to be applied in X rays detection. The photoconduction theory and the physical characteristics of those materials are reviewed. The computer simulation models for studying the photoconductor responses to the radiation pulses are described. The experimental results are discussed. They include the following aspects: the characterization of the GaAs and InP:Fe, in the obscurity, as a function of the polarized electric field and of the neutrons dose; the characterization under X ray. Continuous X rays and pulsed synchrotron radiation are applied [fr

  4. Nuisance Source Population Modeling for Radiation Detection System Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sokkappa, P; Lange, D; Nelson, K; Wheeler, R

    2009-10-05

    A major challenge facing the prospective deployment of radiation detection systems for homeland security applications is the discrimination of radiological or nuclear 'threat sources' from radioactive, but benign, 'nuisance sources'. Common examples of such nuisance sources include naturally occurring radioactive material (NORM), medical patients who have received radioactive drugs for either diagnostics or treatment, and industrial sources. A sensitive detector that cannot distinguish between 'threat' and 'benign' classes will generate false positives which, if sufficiently frequent, will preclude it from being operationally deployed. In this report, we describe a first-principles physics-based modeling approach that is used to approximate the physical properties and corresponding gamma ray spectral signatures of real nuisance sources. Specific models are proposed for the three nuisance source classes - NORM, medical and industrial. The models can be validated against measured data - that is, energy spectra generated with the model can be compared to actual nuisance source data. We show by example how this is done for NORM and medical sources, using data sets obtained from spectroscopic detector deployments for cargo container screening and urban area traffic screening, respectively. In addition to capturing the range of radioactive signatures of individual nuisance sources, a nuisance source population model must generate sources with a frequency of occurrence consistent with that found in actual movement of goods and people. Measured radiation detection data can indicate these frequencies, but, at present, such data are available only for a very limited set of locations and time periods. In this report, we make more general estimates of frequencies for NORM and medical sources using a range of data sources such as shipping manifests and medical treatment statistics. We also identify potential data sources for industrial

  5. The All Terrain Bio nano Gear for Space Radiation Detection System

    International Nuclear Information System (INIS)

    Ummat, Ajay; Mavroidis, Constantinos

    2007-01-01

    This paper discusses about the relevance of detecting space radiations which are very harmful and pose numerous health issues for astronauts. There are many ways to detect radiations, but we present a non-invasive way of detecting them in real-time while an astronaut is in the mission. All Terrain Bio-nano (ATB) gear system is one such concept where we propose to detect various levels of space radiations depending on their intensity and warn the astronaut of probable biological damage. A basic framework for radiation detection system which utilizes bio-nano machines is discussed. This radiation detection system is termed as 'radiation-responsive molecular assembly' (RMA) for the detection of space radiations. Our objective is to create a device which could detect space radiations by creating an environment equivalent to human cells within its structure and bio-chemically sensing the effects induced therein. For creating such an environment and further bio-chemically sensing space radiations bio-nano systems could be potentially used. These bio-nano systems could interact with radiations and signal based on the intensity of the radiations their relative biological effectiveness. Based on the energy and kind of radiation encountered, a matrix of signals has to be created which corresponds to a particular biological effect. The key advantage of such a design is its ability to interact with the radiation at e molecular scale; characterize its intensity based on energy deposition and relate it to the relative biological effectiveness based on the correspondence established through molecular structures and bond strengths of the bio-nano system

  6. Detection and measurement of ionizing radiation by the Radioactive Waste Management Centre

    International Nuclear Information System (INIS)

    Mudra, Josef

    2013-01-01

    The following topics are dealt with: Basic properties of radionuclides and selection of suitable detectors; radiation characteristics of sealed sources (radiation detection, dose rate measurement, surface contamination measurement, gamma spectroscopy); non-destructive analysis (segment gamma scanner, digital radiography); destructive analysis; radiation monitoring of humans and workplaces; and dosimetric monitoring of workplace surroundings and discharges. (orig.)

  7. Development of Functional Foods for Body Protection Using Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Jo, S. K.; Jung, U. H.; Park, H. R.

    2007-07-15

    We have previously developed two herbal compositions(HemoHIM, HemoTonic) that protects immune/hematopoietic system and self-renewal tissues against radiation and enhances immune/hematopoietic functions. In this study, we tried to expand its usability by verifying its protective activity against various harmful stimuli as well as radiation. HemoHIM was shown to be highly effective in reducing immune/hematopoietic damage, particularly, normalizing the Th1/Th2 imbalance, which seemed to be a result of increased production of IL-12p70 by APC and enhanced NK cell activity. Also HemoHIM was shown to have protective activities against UV-induced skin damage, immune system damage by an anticancer drug (CP), immune depression by old age and stress, and inflammation. Finally it was confirmed in a human study that HemoHIM improves the immune cell functions and cytokine production. Based on these results, HemoHIM has been approved as a health functional food for immunomodulation by Korea FDA and succeeded in its industrialization. Meanwhile, to develop functional foods for the reduction of chronic radiation damage (carcinogenesis), we have screened natural products for inhibitory activities against carcinogenesis-related factors, and developed two anti-carcinogenic compositions. Also 6 single compounds were isolated and identified from radioprotective natural products and elucidated some synergistic protection by several single compounds and established a basis for the development of advanced technology for radioprotection. Also, to obtain the applicability of radiation technology for the safe sanitatation and distribution of functional food materials, we verified the toxicological safety, stability of activity and active components of irradiated medicinal herbs

  8. Development of Functional Foods for Body Protection Using Radiation

    International Nuclear Information System (INIS)

    Jo, S. K.; Jung, U. H.; Park, H. R.

    2007-07-01

    We have previously developed two herbal compositions(HemoHIM, HemoTonic) that protects immune/hematopoietic system and self-renewal tissues against radiation and enhances immune/hematopoietic functions. In this study, we tried to expand its usability by verifying its protective activity against various harmful stimuli as well as radiation. HemoHIM was shown to be highly effective in reducing immune/hematopoietic damage, particularly, normalizing the Th1/Th2 imbalance, which seemed to be a result of increased production of IL-12p70 by APC and enhanced NK cell activity. Also HemoHIM was shown to have protective activities against UV-induced skin damage, immune system damage by an anticancer drug (CP), immune depression by old age and stress, and inflammation. Finally it was confirmed in a human study that HemoHIM improves the immune cell functions and cytokine production. Based on these results, HemoHIM has been approved as a health functional food for immunomodulation by Korea FDA and succeeded in its industrialization. Meanwhile, to develop functional foods for the reduction of chronic radiation damage (carcinogenesis), we have screened natural products for inhibitory activities against carcinogenesis-related factors, and developed two anti-carcinogenic compositions. Also 6 single compounds were isolated and identified from radioprotective natural products and elucidated some synergistic protection by several single compounds and established a basis for the development of advanced technology for radioprotection. Also, to obtain the applicability of radiation technology for the safe sanitatation and distribution of functional food materials, we verified the toxicological safety, stability of activity and active components of irradiated medicinal herbs

  9. Time Resolved Detection of Infrared Synchrotron Radiation at DAΦNE

    International Nuclear Information System (INIS)

    Bocci, A.; Marcelli, A.; Drago, A.; Guidi, M. Cestelli; Pace, E.; Piccinini, M.; Sali, D.; Morini, P.; Piotrowski, J.

    2007-01-01

    Synchrotron radiation is characterized by a very wide spectral emission from IR to X-ray wavelengths and a pulsed structure that is a function of the source time structure. In a storage ring, the typical temporal distance between two bunches, whose duration is a few hundreds of picoseconds, is on the nanosecond scale. Therefore, synchrotron radiation sources are a very powerful tools to perform time-resolved experiments that however need extremely fast detectors. Uncooled IR devices optimized for the mid-IR range with sub-nanosecond response time, are now available and can be used for fast detection of intense IR sources such as synchrotron radiation storage rings. We present here different measurements of the pulsed synchrotron radiation emission at DAΦNE (Double Annular Φ-factory for Nice Experiments), the collider of the Laboratori Nazionali of Frascati (LNF) of the Istituto Nazionale di Fisica Nucleare (INFN), performed with very fast uncooled infrared detectors with a time resolution of a few hundreds of picoseconds. We resolved the emission time structure of the electron bunches of the DAΦNE collider when it works in a normal condition for high energy physics experiments with both photovoltaic and photoconductive detectors. Such a technology should pave the way to new diagnostic methods in storage rings, monitoring also source instabilities and bunch dynamics

  10. Calibration of ratemeters used for gamma radiation detection

    International Nuclear Information System (INIS)

    Hantanirina, P.A.

    2017-01-01

    The Secondary Standard Dosimetry Laboratory (SSDL) of INSTN-Madagascar is in charge of the calibration of every dosimetry measurement instrument in hospitals and companies using radioactive sources in Madagascar. It has a secondary standard delivered and calibrated by a Primary Standard Laboratory in Dosimetry (PSLD). This standard is used to compare its reference values with those displayed on the instruments to be calibrated. During our training period, three (3) ratemeters were calibrated, the Graetz X5DE, the Graetz X5C and the Identifinder 2. We have determined the calibration factor for every ratemeter by doing calculation with the reference value. By using the three surveymeters for direct radiations measurements, it has been found that the difference between the displayed values and the real values for every ratemeter does not exceed the tolerance limit which is 20 %. Then we can conclude that these ratemeters are still in good condition of functioning. Concerning the calibration factor curve N_k with the K_a_i_r , we can observe that for the Graetz X5C ratemeter, this curve is almost constant. As well as for the linearity, it is still the Graetz X5C ratemeter which is linear almost integrally for the measured and calculated dose rate values. So we can say that this ratemeter is the most recommended for the radiations measurements.This work which has been carried within the framework of collaboration between the section PNAE (Physique Nucléaire Appliquée et Environnement) of the University of Antananarivo and INSTN-Madagascar has been a good and rewarding experience which allowed us to put into practice all knowledges acquired during our years of studies. [fr

  11. GaN heterostructures for biosensing and radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Howgate, John D.

    2012-12-11

    In this thesis I show the results from our investigation of the interface between gallium nitride wide bandgap semiconductor heterostructures and (bio)molecular systems on their surfaces for biosensing, bioelectronics, and photoelectric applications, with a large emphasis on the processes arising from high energy ionizing irradiation, including heterostructure photoelectric gain mechanisms. Wide bandgap semiconductors, such as gallium nitride, have received increasing attention as potential components in advanced organic/inorganic hybrid systems. Working to further this topic, we determine a new semiconductor alignment required for low energy photo-induced charge transfer ionization of alkyl chains well below the energy normally required for molecular cleavage, show original results of the influence of binding methods on enzyme functionality in conjunction with a novel electrochemical and environmental control system and demonstrate new possibilities to significantly improve upon pH measurements through the use of high sensitivity devices. Furthermore, based on the extension of this work to support future studies of radiation effects on cell systems, we present a detailed characterization of new simultaneous chemical sensing and ionizing radiation dosimetry using single devices. We found that their pH sensitivity was retained during X-ray irradiation and that the fundamental characteristics can be used to separate the irradiation signal from the pH response without compromising operational stability. These data provide clear indications of the separate response mechanism tied to the presence of a two-dimensional electron gas channel. Here, we found new results exhibiting exceptionally high gains and independence of the well-known persistent photoconductivity for soft X-rays and high energy particles in the ultralow dose-rate regime. This material system provides the capability for high sensitivity and resolution real time monitoring, which is competitive with and

  12. GaN heterostructures for biosensing and radiation detection

    International Nuclear Information System (INIS)

    Howgate, John D.

    2012-01-01

    In this thesis I show the results from our investigation of the interface between gallium nitride wide bandgap semiconductor heterostructures and (bio)molecular systems on their surfaces for biosensing, bioelectronics, and photoelectric applications, with a large emphasis on the processes arising from high energy ionizing irradiation, including heterostructure photoelectric gain mechanisms. Wide bandgap semiconductors, such as gallium nitride, have received increasing attention as potential components in advanced organic/inorganic hybrid systems. Working to further this topic, we determine a new semiconductor alignment required for low energy photo-induced charge transfer ionization of alkyl chains well below the energy normally required for molecular cleavage, show original results of the influence of binding methods on enzyme functionality in conjunction with a novel electrochemical and environmental control system and demonstrate new possibilities to significantly improve upon pH measurements through the use of high sensitivity devices. Furthermore, based on the extension of this work to support future studies of radiation effects on cell systems, we present a detailed characterization of new simultaneous chemical sensing and ionizing radiation dosimetry using single devices. We found that their pH sensitivity was retained during X-ray irradiation and that the fundamental characteristics can be used to separate the irradiation signal from the pH response without compromising operational stability. These data provide clear indications of the separate response mechanism tied to the presence of a two-dimensional electron gas channel. Here, we found new results exhibiting exceptionally high gains and independence of the well-known persistent photoconductivity for soft X-rays and high energy particles in the ultralow dose-rate regime. This material system provides the capability for high sensitivity and resolution real time monitoring, which is competitive with and

  13. Radiation Detection System for Prevention of Illicit Trafficking of Nuclear and Radioactive Materials

    International Nuclear Information System (INIS)

    Kwak, Sung Woo; Chang, Sung Soon; Yoo, Ho Sik

    2010-01-01

    Fixed radiation portal monitors (RPMs) deployed at border, seaport, airport and key traffic checkpoints have played an important role in preventing the illicit trafficking and transport of nuclear and radioactive materials. However, the RPM is usually large and heavy and can't easily be moved to different locations. These reasons motivate us to develop a mobile radiation detection system. The objective of this paper is to report our experience on developing the mobile radiation detection system for search and detection of nuclear and radioactive materials during road transport. Field tests to characterize the developed detection system were performed at various speeds and distances between the radioactive isotope (RI) transporting car and the measurement car. Results of measurements and detection limits of our system are described in this paper. The mobile radiation detection system developed should contribute to defending public's health and safety and the environment against nuclear and radiological terrorism by detecting nuclear or radioactive material hidden illegally in a vehicle

  14. Functional size analysis of bioactive materials by radiation inactivation

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    1994-01-01

    When the research on various proteins including enzymes is carried out, first molecular weight is measured. The physical chemical methods used for measuring molecular weight cannot measure it in the state of actually acting in living bodies. Radiation inactivation method is the unique method which can measure the molecular weight of the active substances in living bodies. Paying attention to this point, recently it is attempted to measure the activity unit of enzymes, receptors and others, and to apply to the elucidation of their functions. In this report, the concept of the method of measuring molecular size based on radiation inactivation, the detailed experimental method and the points to which attention must be paid are described. Also its application to the elucidation of living body functions according to the example of the studies by the author is reported. The concept of the measurement of molecular weight by radiation inactivation is based on target theory. The preparation of samples, the effect of oxygen, radiation sources, dosimetry, irradiation temperature, internal standard process and so on are reported. The trend of the research is shown. (K.I.)

  15. Development of thin dosemeters of CaSO4: Dy for beta radiation detection

    International Nuclear Information System (INIS)

    Campos, L.L.

    1987-01-01

    Thin pellets of CaSO: Dy (0,20mm) were produced and tested in beta radiation fields. The Thermolumiscent (TL) characteristics studied were sensitivity, reproducibility, lower detection limit, linearity of TL response with absorved dose energy dependence. The results show the usefulness of this thin pellets in beta radiation detection. (Author) [pt

  16. High Density Nano-Electrode Array for Radiation Detection

    International Nuclear Information System (INIS)

    Misra, Mano

    2010-01-01

    Bulk single crystals of Cd 1-x Zn x Te (x=0.04 to x=0.2) compound semiconductor is used for room temperature radiation detection. The production of large volume of Cd 1-x Zn x Te with low defect density is expensive. As a result there is a growing research interest in the production of nanostructured compound semiconductors such as Cd 1-x Zn x Te in an electrochemical route. In this investigation, Cd 1-x Zn x Te ternary compound semiconductor, referred as CZT, was electrodeposited in the form of nanowires onto a TiO 2 nanotubular template from propylene carbonate as the non-aqueous electrolyte, using a pulse-reverse electrodeposition process at 130 C. The template acted as a support in growing ordered nanowire of CZT which acts as a one dimensional conductor. Cyclic Voltammogram (CV) studies were conducted in determining the potentials for the growth of nanowires of uniform stoichiometry. The morphologies and composition of CZT were characterized by using SEM, TEM and XRD. The STEM mapping carried out on the nanowires showed the uniform distribution of Cd, Zn and Te elements. TEM image showed that the nanowires were polycrystalline in nature. The Mott-Schottky analysis carried on the nanowires showed that the nanowires were a p-type semiconductor. The carrier density, band gap and resistivity of the Cd 0.9 Zn 0.1 Te nanowires were 4.29 x 10 13 cm -3 , 1.56 eV and 2.76 x 10 11 (Omega)-cm respectively. The high resistivity was attributed to the presence of deep defect states such as cadmium vacancies or Te antisites which were created by the anodic cycle of the pulse-reverse electrodeposition process. Stacks of series connected CZT nanowire arrays were tested with different bias potentials. The background current was in the order of tens of picoamperes. When exposed to radiation source Amerecium-241 (60 KeV, 4 (micro)Ci), the stacked CZT nanowires arrays showed sensing behavior. The sensitivity of the nanowire arrays increased as the number of stacks increased. The

  17. High Density Nano-Electrode Array for Radiation Detection

    Energy Technology Data Exchange (ETDEWEB)

    Mano Misra

    2010-05-07

    Bulk single crystals of Cd1-xZnxTe (x=0.04 to x=0.2) compound semiconductor is used for room temperature radiation detection. The production of large volume of Cd1-xZnxTe with low defect density is expensive. As a result there is a growing research interest in the production of nanostructured compound semiconductors such as Cd1-xZnxTe in an electrochemical route. In this investigation, Cd1-xZnxTe ternary compound semiconductor, referred as CZT, was electrodeposited in the form of nanowires onto a TiO2 nanotubular template from propylene carbonate as the non-aqueous electrolyte, using a pulse-reverse electrodeposition process at 130 ºC. The template acted as a support in growing ordered nanowire of CZT which acts as a one dimensional conductor. Cyclic Voltammogram (CV) studies were conducted in determining the potentials for the growth of nanowires of uniform stoichiometry. The morphologies and composition of CZT were characterized by using SEM, TEM and XRD. The STEM mapping carried out on the nanowires showed the uniform distribution of Cd, Zn and Te elements. TEM image showed that the nanowires were polycrystalline in nature. The Mott-Schottky analysis carried on the nanowires showed that the nanowires were a p-type semiconductor. The carrier density, band gap and resistivity of the Cd0.9Zn0.1Te nanowires were 4.29x1013 cm-3, 1.56 eV and 2.76x1011Ω-cm respectively. The high resistivity was attributed to the presence of deep defect states such as cadmium vacancies or Te antisites which were created by the anodic cycle of the pulse-reverse electrodeposition process. Stacks of series connected CZT nanowire arrays were tested with different bias potentials. The background current was in the order of tens of picoamperes. When exposed to radiation source Amerecium-241 (60 KeV, 4 μCi), the stacked CZT nanowires arrays showed sensing behavior. The sensitivity of the nanowire arrays increased as the number of stacks increased. The preliminary results indicate that the

  18. Radiation monitors of new generation - New methodology of detection of nuclear and radioactive materials

    International Nuclear Information System (INIS)

    Kagan, L.; Stavrov, A.

    2001-01-01

    (customs) officers, who as a rule are not experts in the field of radiation control and radiation protection. Therefore, an urgent task for the present is to develop simple, reliable and inexpensive instruments that would allow several of the mentioned tasks to be simultaneously fulfilled. For the last years instruments of a new generation such as the PM1703 and the PM1710 that combine functions of different class devices have been developed. The main distinguishing and favorable features and advantages of these devices are as follows: These devices having small weight and dimensions permit not only effective detection of radioactive sources, but also their location; Special algorithm gives an opportunity to find sources not only with decreasing background as compared to the natural background value due to its shielding (e.g. by scrap), but also with increasing background due to other source (location of one source in the field of the other one); The devices have a non-volatile memory for the history accumulation and storage: time and date of the device switch on/off, source detection cases, etc. The history of operation may be transmitted to the PC for its further storage and processing; The devices have two LCD display modes: in the count rate units (the sources being detected and located in this mode) and in the dose rate units, which allows the evaluation of a danger of the detected and located source to a person. The above-mentioned features of the described devices give an opportunity to develop a new methodology of detection of sources: Owing to small weight and dimensions and a low power consumption the user may hold these devices in a pocket (on a belt) during the entire working shift without switching them off; The user may fulfil his usual professional duties not related to the radiation control and even may not be concerned about the device and its operation - the device functions in the automatic mode and all the information about its operation is accumulated

  19. Rain-Induced Increase in Background Radiation Detected by Radiation Portal Monitors

    Energy Technology Data Exchange (ETDEWEB)

    Hausladen, Paul [ORNL; Blessinger, Christopher S [ORNL; Guzzardo, Tyler [ORNL; Livesay, Jake [ORNL

    2012-07-01

    A complete understanding of both the steady state and transient background measured by Radiation Portal Monitors (RPMs) is essential to predictable system performance, as well as maximization of detection sensitivity. To facilitate this understanding, a test bed for the study of natural background in RPMs has been established at the Oak Ridge National Laboratory. This work was performed in support of the Second Line of Defense Program's mission to detect the illicit movement of nuclear material. In the present work, transient increases in gamma ray counting rates in RPMs due to rain are investigated. The increase in background activity associated with rain, which has been well documented in the field of environmental radioactivity, originates from the atmospheric deposition of two radioactive daughters of radon-222, namely lead-214 and bismuth-214 (henceforth {sup 222}Rn, {sup 214}Pb and {sup 214}Bi). In this study, rainfall rates recorded by a co-located weather station are compared with RPM count rates and High Purity Germanium spectra. The data verifies these radionuclides are responsible for the dominant transient natural background fluctuations in RPMs. Effects on system performance and potential mitigation strategies are discussed.

  20. Detection of functional matrix metalloproteinases by zymography.

    Science.gov (United States)

    Hu, Xueyou; Beeton, Christine

    2010-11-08

    Matrix metalloproteinases (MMPs) are zinc-containing endopeptidases. They degrade proteins by cleavage of peptide bonds. More than twenty MMPs have been identified and are separated into six groups based on their structure and substrate specificity (collagenases, gelatinases, membrane type [MT-MMP], stromelysins, matrilysins, and others). MMPs play a critical role in cell invasion, cartilage degradation, tissue remodeling, wound healing, and embryogenesis. They therefore participate in both normal processes and in the pathogenesis of many diseases, such as rheumatoid arthritis, cancer, or chronic obstructive pulmonary disease. Here, we will focus on MMP-2 (gelatinase A, type IV collagenase), a widely expressed MMP. We will demonstrate how to detect MMP-2 in cell culture supernatants by zymography, a commonly used, simple, and yet very sensitive technique first described in 1980 by C. Heussen and E.B. Dowdle. This technique is semi-quantitative, it can therefore be used to determine MMP levels in test samples when known concentrations of recombinant MMP are loaded on the same gel. Solutions containing MMPs (e.g. cell culture supernatants, urine, or serum) are loaded onto a polyacrylamide gel containing sodium dodecyl sulfate (SDS; to linearize the proteins) and gelatin (substrate for MMP-2). The sample buffer is designed to increase sample viscosity (to facilitate gel loading), provide a tracking dye (bromophenol blue; to monitor sample migration), provide denaturing molecules (to linearize proteins), and control the pH of the sample. Proteins are then allowed to migrate under an electric current in a running buffer designed to provide a constant migration rate. The distance of migration is inversely correlated with the molecular weight of the protein (small proteins move faster through the gel than large proteins do and therefore migrate further down the gel). After migration, the gel is placed in a renaturing buffer to allow proteins to regain their tertiary

  1. Stochastic Radiative Transfer Model for Contaminated Rough Surfaces: A Framework for Detection System Design

    Science.gov (United States)

    2013-11-01

    example for the detection of a potassium chlorate contaminated “car” with a CO2 tunable laser system. 15. SUBJECT TERMS Radiative transfer...detector m-out-of-n detector Potassium chlorate Probability theory System performance Probability of detection and false alarm iii...for the detection of a potassium chlorate contaminated “car” with a CO2 tunable laser system. Subject Terms Radiative transfer, contaminated

  2. Radial basis function neural network in fault detection of automotive ...

    African Journals Online (AJOL)

    Radial basis function neural network in fault detection of automotive engines. ... Five faults have been simulated on the MVEM, including three sensor faults, one component fault and one actuator fault. The three sensor faults ... Keywords: Automotive engine, independent RBFNN model, RBF neural network, fault detection

  3. Radiation and detectors introduction to the physics of radiation and detection devices

    CERN Document Server

    Cerrito, Lucio

    2017-01-01

    This textbook provides an introduction to radiation, the principles of interaction between radiation and matter, and the exploitation of those principles in the design of modern radiation detectors. Both radiation and detectors are given equal attention and their interplay is carefully laid out with few assumptions made about the prior knowledge of the student. Part I is dedicated to radiation, broadly interpreted in terms of energy and type, starting with an overview of particles and forces, an extended review of common natural and man-made sources of radiation, and an introduction to particle accelerators. Particular attention is paid to real life examples, which place the types of radiation and their energy in context. Dosimetry is presented from a modern, user-led point of view, and relativistic kinematics is introduced to give the basic knowledge needed to handle the more formal aspects of radiation dynamics and interaction. The explanation of the physics principles of interaction between radiation an...

  4. Detection device of dangerous radiation for the living beings

    International Nuclear Information System (INIS)

    Lacoste, F.

    1991-01-01

    This invention is about a portable device able to measure dose rates or doses of gamma, ultraviolet and X radiation or charged particles. This device is composed of a radiation detector, a calculator of the accumulate dose and a memory to store the data. This device has a credit card format

  5. Radiation Protection in the Application of Active Detection Technologies

    Science.gov (United States)

    2013-07-01

    BECKER, S.M. (2004). “Emergency communication and information issues in terrorism events involving radioactive materials,” Biosecur Bioterror. 2(3...National Council on Radiation Protection and Measurements. Considerations Regarding the Unintended Radiation Exposure of the Embryo, Fetus or Nursing

  6. On advisability of developing automatic complexes of radiation flow detection

    International Nuclear Information System (INIS)

    Akopov, V.S.; Voronin, S.A.; Meshalkin, I.A.

    1976-01-01

    On the basis of mathematical treatment of statistical data obtained by inquest of specialists from a number of factories, problems associated with the determination of the most acceptable efficiency of radiation defectoscopy automatized complexes are considered. Production requirements for radiation control sensitivity are generalized. The use of providing the complexes with computer technique is substantiated

  7. Proposal of secure camera-based radiation warning system for nuclear detection

    International Nuclear Information System (INIS)

    Tsuchiya, Ken'ichi; Kurosawa, Kenji; Akiba, Norimitsu; Kakuda, Hidetoshi; Imoto, Daisuke; Hirabayashi, Manato; Kuroki, Kenro

    2016-01-01

    Counter-terrorisms against radiological and nuclear threat are significant issues toward Tokyo 2020 Olympic and Paralympic Games. In terms of cost benefit, it is not easy to build a warning system for nuclear detection to prevent a Dirty Bomb attack (dispersion of radioactive materials using a conventional explosive) or a Silent Source attack (hidden radioactive materials) from occurring. We propose a nuclear detection system using the installed secure cameras. We describe a method to estimate radiation dose from noise pattern in CCD images caused by radiation. Some dosimeters under neutron and gamma-ray irradiations (0.1mSv-100mSv) were taken in CCD video camera. We confirmed amount of noise in CCD images increased in radiation exposure. The radiation detection using CMOS in secure cameras or cell phones has been implemented. However, in this presentation, we propose a warning system including neutron detection to search shielded nuclear materials or radiation exposure devices using criticality. (author)

  8. Application of organic semiconductors for the detection of ionizing radiations

    International Nuclear Information System (INIS)

    Kozelj, M.; Cvikl, B.; Korosak, D.

    2006-01-01

    One year aged organic bilayer Al/PCTDA/CuPc/ITO structure prepared with ICB deposition method has been used to evaluate the influence of ionising radiation to electrical properties of the structure. Small sources of α, β and γ radiation were used for preliminary measurements. Capacitance and current measurements were performed on samples with and without presence of ionising radiation and results compared. Effect of β and γ radiation has not been confirmed due to the limited activity of available sources. Presence of α radiation has noticeably changed the capacitance of reversely biased structure and produced increase of current through the structure. We have tried to explain the capacitance properties using the model previously developed for the organic bilayer structures, but we did not manage to resolve all effects involved. (author)

  9. The study on the immunity restoring function of cWPROL in treating experimental radiation esophagitis

    International Nuclear Information System (INIS)

    Shen Li; Shan Baoen; Zhang Li; Lu Fuhe; Guo Xiujuan

    2007-01-01

    Objective: To study the restorative function of compound white peony root oral liquids (cWPROL) in treating rats' experimental acute radiation-induced esophagitis from the aspect of immunodeficiency. Methods: 128 Wistar rats were divided into eight groups. The radiation esophagitis was induced by 43 Gy 60 Co. Then the rats were treated with medicine in different ways. On every experimental point the absolute number and percentage of T lymphocyte subsets were analyzed by flow cytometry. The changes of the leukocyte in number and differential count were detected by haemocyte counting instrument. IgG and C3 in rats' serum were analyzed by immunological turbidimetry. Results: Radiation brought on decrease of experimental rats 'leukocyte count, the lymphocyte differential count, absolute count and absolute T lymphocyte subsets in the blood and the content of IgG and C3 with radiation esophagitis. cWPROL could increase the lymphocyte percentage compared that in with the radiated group 2. The preventive (high dose) could increase lymphocyte count while Western medicine decreased rats' leukocyte count, lymphocyte percentage and absolute count (P<0.05). The absolute T lymphocyte subsets in rats' peripheral blood increased in the group infused with cWPROL (high dose) (P<0.001). Compared with the radiated group 2 the absolute T lymphocyte subsets decreased significantly(P<0.001), and the content of complement C3 increased in the group infused with cWPROL (high dose) (P<0.05) but decreased in the group infused with Western medicine (P<0.01). Conclusion: cWPROL plays the role of restoring the cytoimmunity and immunity damaged by radiation in rats with radiation esophagitis. (authors)

  10. Alpha radiation detection using silicon memory chips - preliminary studies

    International Nuclear Information System (INIS)

    Pace, R.; Paix, D.; Haskard, M.

    1993-01-01

    Alpha radiation dosage is an important occupational health factor in the mining of uranium and mineral sands. Alpha radiation induced errors in the data of silicon based memory chips provide the foundation for a new type of sensor, with the potential for affordable and prompt measurement of personal alpha doses. With particular reference to Dynamic Random Access Memories (DRAM) this paper introduces the operating principle of a memory based radiation sensor, which is the error mechanism in silicon integrated circuits. 14 refs., 3 figs

  11. Development of Sensor Technology and Its Application for Nuclear Radiation Detection

    International Nuclear Information System (INIS)

    Hiskia

    2007-01-01

    Radiation is energy in the form of waves or moving subatomic particles. Radiation can be ionizing or nonionizing radiation, depending on its effect on atomic matter. Because radiation cannot be seen, felt, tasted, heard or smelled, even at lethal levels, radiations detection devices must be used to alert those exposed to radiation. The measurement of radioactivity in the environment is a regulatory requirement around sites where significant amounts of radioactive materials are used or stored. Recently, advent in microelectronics and material technology has enabled to produce small sensor or microsensor, sensitive, accurate, and integrated in a chip or substrate. Development of radiation sensor technology using thin/thick film and micromachining technique was described in this paper. Indonesian capabilities in radiation sensor research and development and opportunities for commercialization also given. (author)

  12. The Development of Sensor Technology and Application to Detect Nuclear Radiation

    International Nuclear Information System (INIS)

    Hiskia

    2007-01-01

    Radiation is energy in the form of waves or moving subatomic particles. Radiation can be ionizing or non-ionizing radiation, depending on its effect on atomic matter. Because radiation cannot be seen, felt, tasted, heard or smelled, even at lethal levels, radiations detection devices must be used to alert those exposed to radiation. The measurement of radioactivity in the environment is a regulatory requirement around sites where significant amounts of radioactive materials are used or stored. Recently, advent in microelectronics and material technology has enabled to produce small sensor or microsensor, sensitive, accurate, and integrated in a chip or substrate. Development of radiation sensor technology using thin/thick film and micromachining technique was described in this paper. Indonesian capabilities in radiation sensor research and development and opportunities for commercialization also given. (author)

  13. Shining light on radiation detection and energy transfer : Triazole ligands used for detection of radiation and lanthanide binding

    NARCIS (Netherlands)

    Dijkstra, Peter

    2016-01-01

    Some substances, fluorophores, absorb light and then emit that light again as fluorescence. Apart from absorption of light, some of these substances can also emit light after having absorbed energy from radiation. A substance which can absorb radiation and emit the energy as light is called a

  14. Einstein as Armchair Detective: The Case of Stimulated Radiation

    Indian Academy of Sciences (India)

    theory and of gravity in the case of the general theory. It might be argued that the ... the radiation density p at different frequencies through. Planck's law. He assumes .... derive both Planck's law and Bohr's principle based on these hypotheses.

  15. Development of radiation hardened pixel sensors for charged particle detection

    CERN Document Server

    Koziel, Michal

    2014-01-01

    CMOS Pixel Sensors are being developed since a few years to equip vertex detectors for future high-energy physics experiments with the crucial advantages of a low material budget and low production costs. The features simultaneously required are a short readout time, high granularity and high tolerance to radiation. This thesis mainly focuses on the radiation tolerance studies. To achieve the targeted readout time (tens of microseconds), the sensor pixel readout was organized in parallel columns restricting in addition the readout to pixels that had collected the signal charge. The pixels became then more complex, and consequently more sensitive to radiation. Different in-pixel architectures were studied and it was concluded that the tolerance to ionizing radiation was limited to 300 krad with the 0.35- m fabrication process currently used, while the targeted value was several Mrad. Improving this situation calls for implementation of the sensors in processes with a smaller feature size which naturally imp...

  16. TERA-MIR radiation: materials, generation, detection and applications III (Conference Presentation)

    Science.gov (United States)

    Pereira, Mauro F.

    2016-10-01

    This talk summarizes the achievements of COST ACTION MP1204 during the last four years. [M.F. Pereira, Opt Quant Electron 47, 815-820 (2015).]. TERA-MIR main objectives are to advance novel materials, concepts and device designs for generating and detecting THz and Mid Infrared radiation using semiconductor, superconductor, metamaterials and lasers and to beneficially exploit their common aspects within a synergetic approach. We used the unique networking and capacity-building capabilities provided by the COST framework to unify these two spectral domains from their common aspects of sources, detectors, materials and applications. We created a platform to investigate interdisciplinary topics in Physics, Electrical Engineering and Technology, Applied Chemistry, Materials Sciences and Biology and Radio Astronomy. The main emphasis has been on new fundamental material properties, concepts and device designs that are likely to open the way to new products or to the exploitation of new technologies in the fields of sensing, healthcare, biology, and industrial applications. End users are: research centres, academic, well-established and start-up Companies and hospitals. Results are presented along our main lines of research: Intersubband materials and devices with applications to fingerprint spectroscopy; Metamaterials, photonic crystals and new functionalities; Nonlinearities and interaction of radiation with matter including biomaterials; Generation and Detection based on Nitrides and Bismides. The talk is closed by indicating the future direction of the network that will remain active beyond the funding period and our expectations for future joint research.

  17. Sexual function after surgical and radiation therapy for cervical carcinoma

    International Nuclear Information System (INIS)

    Seibel, M.; Freeman, M.G.; Graves, W.L.

    1982-01-01

    One hundred women treated for carcinoma of the cervix were interviewed more than one year later to establish the effects of radiation or surgical therapy on sexual function. Forty-three had received irradiation, 44 nonradical surgery, six combined surgery and irradiation, and seven radical surgery. The irradiation and nonradical surgery groups were each further subdivided into subgroups of patients aged 30 to 49 for age-controlled comparison. Patients in the irradiation group had statistically significant decreases in sexual enjoyment, ability to attain orgasm, coital opportunity, frequency of intercourse, and coital desire. The group who had nonradical surgical procedures had no significant change in sexual function after treatment. Similar results were found in both age-controlled subgroups, eliminating age as a major etiologic factor. Marked vaginal alterations were recorded in the majority of irradiated patients, but were not present among the groups treated with nonradical surgery. The vaginal changes alone could not be held accountable for the significant decrease in sexual function among women who received pelvic irradiation. The origin of decreased sexual desire after radiation therapy is complex, and not yet completely understood. We propose therapeutic programs to help women deal with the emotional and physical consequences of pelvic irradiation

  18. Renal function changes associated with aging and ionizing radiation

    International Nuclear Information System (INIS)

    Miller, C.W.; Norrdin, R.W.; Sawyer, S.S.; Nealeigh, R.C.

    1978-01-01

    Renal function testing of irradiated and unirradiated beagles at CRHL has been carried out for the past 7 years using a simultaneous estimation of sodium sulfanilate and sodium iodohippurate 131 I clearance. Evidence has been cited that the beagle kidney is markedly sensitive to whole-body ionizing radiation delivered in the perinatal period. The objectives of this continuing study are to determine the nature of the progression of chronic renal disease, its possible association to hypertension, the impact of unilateral nephrectomy upon an already compromised renal parenchyma, and the age-related changes in renal function. Thus far, data seem to indicate the following conclusions: sulfanilate clearance appears to be a sensitive indicator of impending renal failure, exhibiting earlier and more obvious indicators than BUN (blood urea nitrogen) levels; hypertension does not appear to be a factor in radiation-induced renal failure in the adult dogs studied here, since the average arterial blood pressure was as high in normal control dogs as in irradiated dogs suffering from renal failure; unilateral nephrectomy affected unirradiated dogs less than irradiated animals with mild renal insufficiency. The BUN levels returned to prenephrectomy levels in 8 weeks in the unirradiated group, but required up to 1 year in the dogs with renal insufficiency; and an age related decrease inrenal function was observed in a group of unirradiated dogs studied from 0 to 2 through 13 years of age

  19. Sexual function after surgical and radiation therapy for cervical carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Seibel, M. (Beth Israel Hospital, Boston, MA); Freeman, M.G.; Graves, W.L.

    1982-10-01

    One hundred women treated for carcinoma of the cervix were interviewed more than one year later to establish the effects of radiation or surgical therapy on sexual function. Forty-three had received irradiation, 44 nonradical surgery, six combined surgery and irradiation, and seven radical surgery. The irradiation and nonradical surgery groups were each further subdivided into subgroups of patients aged 30 to 49 for age-controlled comparison. Patients in the irradiation group had statistically significant decreases in sexual enjoyment, ability to attain orgasm, coital opportunity, frequency of intercourse, and coital desire. The group who had nonradical surgical procedures had no significant change in sexual function after treatment. Similar results were found in both age-controlled subgroups, eliminating age as a major etiologic factor. Marked vaginal alterations were recorded in the majority of irradiated patients, but were not present among the groups treated with nonradical surgery. The vaginal changes alone could not be held accountable for the significant decrease in sexual function among women who received pelvic irradiation. The origin of decreased sexual desire after radiation therapy is complex, and not yet completely understood. We propose therapeutic programs to help women deal with the emotional and physical consequences of pelvic irradiation.

  20. A Method for Improving Reliability of Radiation Detection using Deep Learning Framework

    International Nuclear Information System (INIS)

    Chang, Hojong; Kim, Tae-Ho; Han, Byunghun; Kim, Hyunduk; Kim, Ki-duk

    2017-01-01

    Radiation detection is essential technology for overall field of radiation and nuclear engineering. Previously, technology for radiation detection composes of preparation of the table of the input spectrum to output spectrum in advance, which requires simulation of numerous predicted output spectrum with simulation using parameters modeling the spectrum. In this paper, we propose new technique to improve the performance of radiation detector. The software in the radiation detector has been stagnant for a while with possible intrinsic error of simulation. In the proposed method, to predict the input source using output spectrum measured by radiation detector is performed using deep neural network. With highly complex model, we expect that the complex pattern between data and the label can be captured well. Furthermore, the radiation detector should be calibrated regularly and beforehand. We propose a method to calibrate radiation detector using GAN. We hope that the power of deep learning may also reach to radiation detectors and make huge improvement on the field. Using improved radiation detector, the reliability of detection would be confident, and there are many tasks remaining to solve using deep learning in nuclear engineering society.

  1. Development of a distributed radiation detection system using optical fibers

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, F; Inouchi, Goro; Takada, Eiji; Takahashi, Hiroyuki; Iguchi, Tetsuo; Nakazawa, Masaharu [Tokyo Univ. (Japan). Faculty of Engineering; Kakuta, Tsunemi

    1996-07-01

    We have confirmed the importance of temperature and dose rate for the response of Ge-doped fibers to radiation. A phenomenological model have been found to account for temperature and dose rate effects. From this model it is possible to make dose predictions from attenuation measurements when the temperature and dose rate are known. Ge-doped fibers have been found to have a relatively low sensitivity to both neutron and gamma radiation. In addition, temperature and dose rate dependencies complicate the analysis. However we point out that these problems may all be solved if we use fibers, such as P-doped fibers, which contain color centers of long lifetime. This would remove both the temperature and dose rate dependencies that complicate the use of Ge-doped fibers, in addition the radiation sensitivity is increased. Finally OTDR has been investigated as a possible read-out method for distributed radiation measurements. For our system the minimum pulse length was 3ns, giving a spatial resolution in the meter range and a response length to radiation of about 10 m if accurate dose values where to be obtained. We found OTDR to be a suitable method for radiation induced attenuation measurements in optical fibers, especially for long fiber lengths and long time scales where questions of light source stability becomes important for other systems. (S.Y.)

  2. A point mutation of human p53, which was not detected as a mutation by a yeast functional assay, led to apoptosis but not p21Waf1/Cip1/Sdi1 expression in response to ionizing radiation in a human osteosarcoma cell line, Saos-2

    International Nuclear Information System (INIS)

    Okaichi, Kumio; Wang Lihong; Sasaki, Ji-ichiro; Saya, Hideyuki; Tada, Mitsuhiro; Okumura, Yutaka

    1999-01-01

    Purpose: The 123A point mutation of p53 showed increased radiosensitivity, whereas other mutations (143A, 175H, and 273H) were not affected. To determine the reason for increased radiosensitivity of the 123A mutation, the response of the transformant of 123A mutation to ionizing radiation (IR) was examined and compared to those of transformants with the wild type p53 or other point mutations (143A, 175H, and 273H). Methods and Materials: Stable transformants with a mutant or wild type p53 made by introducing cDNA into the human osteosarcoma cell line, Saos-2, which lacks an endogenous p53 were used. The transcriptional activity of mutant p53 was examined using a yeast functional assay. The transformants were examined for the accumulation of p53, the induction of p21 Waf1/Cip1/Sdi1 (hereafter referred to as p21), and the other response of p53-responsive genes (MDM2, Bax, and Bcl-2) by Western blotting. Apoptosis was analyzed by detection of DNA fragmentation. Results: The 123A point mutation of p53 was detected as a wild type in the yeast functional assay. The 123A mutant accumulated p53 in response to IR. The 123A mutant did not induce p21, but normally responded to MDM2, Bax, and Bcl-2. The 123A mutant entered apoptosis earlier than the wild type p53 transformant, and induced Fas at earlier in response to IR. Conclusion: The 123A mutant led to apoptosis, but not p21 expression in response to IR. The occurrence of apoptosis, but not induction of p21, corresponded to the radiosensitivity in the transformant. The early occurrence of apoptosis in 123A transformants may depend on the early induction of Fas

  3. Synchrotron radiation and atom pair correlation functions in electrolyte solutions

    International Nuclear Information System (INIS)

    Triolo, R.; D'Aprano, A.

    1978-01-01

    Despite the enormous effort invested in experimental determinations of the properties of water and aqueous solutions, understanding is still rudimentary. Many of the problems are consequences of a nonrigorous definition of interparticle interactions. It is now clear that after properly ion--water interactions in terms of probability functions of position and orientation it is possible to probe these interactions at molecular levels using diffraction experiments. The role of synchrotron x-ray radiation in this context is being examined. Emphasis is given to the possibility of performing different experiments analogous to those done using the isotopic substitution method in neutron diffraction

  4. Radiation-induced changes in gustatory function comparison of effects of neutron and photon irradiation

    International Nuclear Information System (INIS)

    Mossman, K.L.; Chencharick, J.D.; Scheer, A.C.; Walker, W.P.; Ornitz, R.D.; Rogers, C.C.; Henkin, R.I.

    1979-01-01

    Changes in gustatory function were measured in 51 patients with various forms of cancer who received radiation to the head and neck region. Forty patients (group I) were treated with conventional photon radiation (e.g. 66 Gy/7 weeks), and 11 patients (group II) were treated with cyclotron produced fast neutrons (e.g. 22 Gy/7 weeks). Taste acuity was measured for four taste qualities (salt, sweet, sour, and bitter) by a forced choice-three stimulus drop technique which measured detection and recognition thresholds and by a forced scaling technique which measured taste intensity responsiveness. Subjective complaints of anorexia, dysgeusia, taste loss, and xerostomia were also recorded. Patients were studied before, during and up to two months after therapy. Prior to therapy, detection and recognition thresholds, intensity responsiveness, and the frequency of subjective complaints in patients from groups I and II were statistically equivalent. During and up to 2 months after therapy, taste impairment and frequency of subjective complaints increased significantly in neutron and photon treated patients, but were statistically equivalent. Results of this study indicate that gustatory tissue response as measured by taste detection and recognition and intensity responsiveness, and the frequency of subjective complaints related to taste are statistically equivalent in patients before, during, or up 2 months after they were given either neutron or photon radiation for tumors of the head and neck

  5. The central monitoring station of Indian Environmental Radiation Monitoring Network (IERMON): the architecture and functions

    International Nuclear Information System (INIS)

    Garg, Saurabh; Ratheesh, M.P.; Mukundan, T.; Patel, M.D.; Nair, C.K.G.; Puranik, V.D.

    2010-01-01

    The Indian Environmental Radiation Monitoring Network (IERMON) is being established across the country by the Bhabha Atomic Research Centre, Mumbai. The network consists of stations with automated systems for environmental radiation monitoring with online data communication facility. Currently about 100 stations are operational and additional 500 stations are expected to be installed by March, 2012. The network is established with different objectives, the main objective being the detection and reporting of any nuclear emergency anywhere in the country. The central monitoring station of the network is established in Mumbai. This paper describes the architecture and functions of IERMON Central Station. The Central Station consists of server room for online data collection from remote stations and maintenance of databases for various applications; central monitoring room for user interaction with database and IERMON website maintenance and development room for the development of new applications. The functions of IERMON Central Station include detection and reporting of nuclear emergency, maintenance of remote stations, enhancement of public awareness on environmental radiation through public display systems and website, etc. The details on system layout and data protocols can be found in the paper. (author)

  6. Hand-held, mechanically cooled, radiation detection system for gamma-ray spectroscopy

    Science.gov (United States)

    Burks, Morgan Thomas; Eckels, Joel Del

    2010-06-08

    In one embodiment, a radiation detection system is provided including a radiation detector and a first enclosure encapsulating the radiation detector, the first enclosure including a low-emissivity infra-red (IR) reflective coating used to thermally isolate the radiation detector. Additionally, a second enclosure encapsulating the first enclosure is included, the first enclosure being suspension mounted to the second enclosure. Further, a cooler capable of cooling the radiation detector is included. Still yet, a first cooling interface positioned on the second enclosure is included for coupling the cooler and the first enclosure. Furthermore, a second cooling interface positioned on the second enclosure and capable of coupling the first enclosure to a cooler separate from the radiation detection system is included. Other embodiments are also presented.

  7. X-ray spectral determination by detection of radiation scattered at different angles

    International Nuclear Information System (INIS)

    Barrea, Raul; Mainardi, R.T.

    1987-01-01

    A precise knowledge of the spectral content of an X-ray beam is of fundamental importance in areas such as X-ray fluorescence analysis by absolute methods, radiodiagnosis, radiotherapy, computed tomography, etc. A simple practical method was developed to determine X-ray spectra emitted by X-ray tubes. It is based on the scattering of the beam on a solid target and detection of this radiation at different angles. This methodology can easily be adapted to the successive attenuation of the beam procedure. Numerical parameter values of a proposed analytical function for the energy spectrum are found measuring the radiation intensity with a suitable detector (ionization chamber or plastic scintillation detector) and equating it with the convolution integral of the proposed spectrum with the incoherent scattering function. This procedure of spectra determination is enclosed in the same group of those generically referred as successive modifications of the irradiation set up used in absolute methods of X-ray fluorescence analysis. (Author) [es

  8. Non-Destructive Detection and Separation of Radiation Damaged Cells in Miniaturized, Inexpensive Device, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — There is a clear and well-identified need for rapid, efficient, non-destructive detection and isolation of radiation damaged cells. Available commercial technologies...

  9. Exciton distribution function and secondary radiation in polar semiconductors

    International Nuclear Information System (INIS)

    Trallero Giner, C.; Sotolongo Costa, O.

    1985-07-01

    An explicit non-equilibrium distribution function for excitons in the ground state n=1 in the case when the fundamental interaction is with acoustical phonons is calculated for polar semiconductors. Using it, a general expression for the secondary radiation cross-section (valid for Raman, hot and thermalized luminescence processes), is obtained. The results are applied to explain the temperature dependence of the 1LO and 2LO luminescence lines half-width in CdS single crystals. The relative contributions of 3LO Raman and luminescence intensities and the variation of the secondary emission spectrum as function of exciton life-time are studied. Comparison with experimental results yields quantitative agreement. (author)

  10. An investigation of medical radiation detection using CMOS image sensors in smartphones

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Han Gyu [Department of Senior Healthcare, Graduate School of Eulji University, Daejeon 301-746 (Korea, Republic of); Song, Jae-Jun [Department of Otorhinolaryngology-Head & Neck Surgery, Korea University, Guro Hospital,148, Gurodong-ro, Guro-gu, Seoul 152-703 (Korea, Republic of); Lee, Kwonhee [Graduate Program in Bio-medical Science, Korea University, 2511 Sejong-ro, Sejong City 339-770 (Korea, Republic of); Nam, Ki Chang [Department of Medical Engineering, College of Medicine, Dongguk University, 32 Dongguk-ro, Goyang-si, Gyeonggi-do 410-820 (Korea, Republic of); Hong, Seong Jong; Kim, Ho Chul [Department of Radiological Science, Eulji University, 553 Yangji-dong, Sujeong-gu, Seongnam-si, Gyeonggi-do 431-713 (Korea, Republic of)

    2016-07-01

    Medical radiation exposure to patients has increased with the development of diagnostic X-ray devices and multi-channel computed tomography (CT). Despite the fact that the low-dose CT technique can significantly reduce medical radiation exposure to patients, the increasing number of CT examinations has increased the total medical radiation exposure to patients. Therefore, medical radiation exposure to patients should be monitored to prevent cancers caused by diagnostic radiation. However, without using thermoluminescence or glass dosimeters, it is hardly measure doses received by patients during medical examinations accurately. Hence, it is necessary to develop radiation monitoring devices and algorithms that are reasonably priced and have superior radiation detection efficiencies. The aim of this study is to investigate the feasibility of medical dose measurement using complementary metal oxide semiconductor (CMOS) sensors in smartphone cameras with an algorithm to extract the X-ray interacted pixels. We characterized the responses of the CMOS sensors in a smartphone with respect to the X-rays generated by a general diagnostic X-ray system. The characteristics of the CMOS sensors in a smartphone camera, such as dose response linearity, dose rate dependence, energy dependence, angular dependence, and minimum detectable activity were evaluated. The high energy gamma-ray of 662 keV from Cs-137 can be detected using the smartphone camera. The smartphone cameras which employ the developed algorithm can detect medical radiations.

  11. An investigation of medical radiation detection using CMOS image sensors in smartphones

    International Nuclear Information System (INIS)

    Kang, Han Gyu; Song, Jae-Jun; Lee, Kwonhee; Nam, Ki Chang; Hong, Seong Jong; Kim, Ho Chul

    2016-01-01

    Medical radiation exposure to patients has increased with the development of diagnostic X-ray devices and multi-channel computed tomography (CT). Despite the fact that the low-dose CT technique can significantly reduce medical radiation exposure to patients, the increasing number of CT examinations has increased the total medical radiation exposure to patients. Therefore, medical radiation exposure to patients should be monitored to prevent cancers caused by diagnostic radiation. However, without using thermoluminescence or glass dosimeters, it is hardly measure doses received by patients during medical examinations accurately. Hence, it is necessary to develop radiation monitoring devices and algorithms that are reasonably priced and have superior radiation detection efficiencies. The aim of this study is to investigate the feasibility of medical dose measurement using complementary metal oxide semiconductor (CMOS) sensors in smartphone cameras with an algorithm to extract the X-ray interacted pixels. We characterized the responses of the CMOS sensors in a smartphone with respect to the X-rays generated by a general diagnostic X-ray system. The characteristics of the CMOS sensors in a smartphone camera, such as dose response linearity, dose rate dependence, energy dependence, angular dependence, and minimum detectable activity were evaluated. The high energy gamma-ray of 662 keV from Cs-137 can be detected using the smartphone camera. The smartphone cameras which employ the developed algorithm can detect medical radiations.

  12. Highly sensitive detection of ionizing radiations by a photoluminescent uranyl organic framework

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Jian; Wang, Yaxing; Liu, Wei; Yin, Xuemiao; Chen, Lanhua; Diwu, Juan; Chai, Zhifang; Wang, Shuao [School for Radiological and interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou (China); Zou, Youming [High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui (China); Albrecht-Schmitt, Thomas E. [Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL (United States); Liu, Guokui [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL (United States)

    2017-06-19

    Precise detection of low-dose X- and γ-radiations remains a challenge and is particularly important for studying biological effects under low-dose ionizing radiation, safety control in medical radiation treatment, survey of environmental radiation background, and monitoring cosmic radiations. We report here a photoluminescent uranium organic framework, whose photoluminescence intensity can be accurately correlated with the exposure dose of X- or γ-radiations. This allows for precise and instant detection of ionizing radiations down to the level of 10{sup -4} Gy, representing a significant improvement on the detection limit of approximately two orders of magnitude, compared to other chemical dosimeters reported up to now. The electron paramagnetic resonance analysis suggests that with the exposure to radiations, the carbonyl double bonds break affording oxo-radicals that can be stabilized within the conjugated uranium oxalate-carboxylate sheet. This gives rise to a substantially enhanced equatorial bonding of the uranyl(VI) ions as elucidated by the single-crystal structure of the γ-ray irradiated material, and subsequently leads to a very effective photoluminescence quenching through phonon-assisted relaxation. The quenched sample can be easily recovered by heating, enabling recycled detection for multiple runs. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Application of CVD diamond film for radiation detection

    International Nuclear Information System (INIS)

    Zhou Haiyang; Zhu Xiaodong; Zhan Rujuan

    2005-01-01

    With the development of diamond synthesis at low pressure, the CVD diamond properties including electronic characteristics have improved continuously. Now the fabrication of electronic devices based on the CVD diamond has been one of hot research subjects in this field. Due to many unique advantages, such as high signal-noise ratio, fast time response, and normal output in extremely harsh surrounding, the CVD diamond radiation detector has attracted more and more interest. In this paper, we have reviewed the development and status of the CVD diamond radiation detector. The prospect of this detector is described. (authors)

  14. Detection of nuclear radiations; Deteccion de Radiaciones nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Tanarro Sanz, A

    1967-07-01

    A summary of the lectures about the ordinary detectors of nuclear radiations explained by the author in the courses of Nuclear Engineering held at the J.E.N. up to the date of publication is given. Those lectures are considered to be a necessary introduction to Nuclear Instrumentation and Applied Electronics to Nuclear Engineering so it has been intended to underline those characteristics of radiation detectors that must be taken in consideration in choosing or designing the electronic equipment associated to them in order to take advantage of each detector possibilities. (Author)

  15. Detection of nuclear radiations; Detectores de radiaciones nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Tanarro Sanz, A

    1959-07-01

    A summary of the lectures about the ordinary detectors of nuclear radiations given by the author in the Courses of Introduction to Nuclear Engineering held at the JEN up to the date of publication is given. Those lectures are considered to be a necessary introduction to Nuclear Instrumentation and Applied electronics to Nuclear Engineering so it has been intent to underline those characteristics of radiation detectors that must be taken in consideration in choosing or designing the electronic equipment associated to them in order to take advantage of each detector possibilities. (Author) 8 refs.

  16. Thermoluminescence analysis for detection of irradiated food - luminescence characteristics of minerals for different types of radiation and radiation doses

    International Nuclear Information System (INIS)

    Soika, C.; Delincée, H.

    2000-01-01

    Federal Research Centre for Nutrition, Institute of Nutritional Physiology, Haid-und-Neu-Straße 9, 76131 Karlsruhe (Germany) Thermoluminescence analysis is used to detect radiation processing of foods which are contaminated with sand or dust. Silicate minerals are isolated, their radiation-induced luminescence is measured and compared to the thermoluminescence from a second measurement after exposure to a dexned radiation dose (normalization). In the present study, the mineral mixture *sand+ and its main components feldspar and quartz were investigated for their thermoluminescence behaviour using different types of radiation, in order to determine adequate radiation sources for the purpose of normalization. The material was irradiated with types of ionizing radiation commonly used for commercial food irradiation, i.e. accelerated electrons with beam energies of 5 MeV as well as 10 MeV, and 60 Co--rays. After thermoluminescence measurements, samples were re-irradiated using either accelerated electrons with beam energies of 2 MeV, 5 MeV or 10 MeV, or 60 Co--rays, 90 Sr--rays or ultraviolet rays (200}280 nm). Evaluation of the xrst and corresponding second glow curve revealed that their shapes depend on the type of minerals in the mixture. The second radiation treatment (normalization) is satisfactory when accelerated electrons (2, 5 and 10 MeV) as well as 60 Co--rays and 90 Sr--rays are employed. Normalization with ultraviolet rays, however, has only a limited range of use

  17. Nanotechnology-Based Systems for Nuclear Radiation and Chemical Detection

    International Nuclear Information System (INIS)

    Kody Varahramyan; Pedro Derosa; Chester Wilson

    2006-01-01

    This main objectives of this effort are the development and prototyping of a small, sensitive, and low-cost multi-channel nanoparticle scintillation microdevice with integrated waveguides for alpha, beta, gamma, and neutron detection. This research effort has integrated experiments and simulation to determine the combination of process-specific materials for the achievement optimum detection conditions

  18. Standoff alpha radiation detection for hot cell imaging and crime scene investigation

    Science.gov (United States)

    Kerst, Thomas; Sand, Johan; Ihantola, Sakari; Peräjärvi, Kari; Nicholl, Adrian; Hrnecek, Erich; Toivonen, Harri; Toivonen, Juha

    2018-02-01

    This paper presents the remote detection of alpha contamination in a nuclear facility. Alpha-active material in a shielded nuclear radiation containment chamber has been localized by optical means. Furthermore, sources of radiation danger have been identified in a staged crime scene setting. For this purpose, an electron-multiplying charge-coupled device camera was used to capture photons generated by alpha-induced air scintillation (radioluminescence). The detected radioluminescence was superimposed with a regular photograph to reveal the origin of the light and thereby the alpha radioactive material. The experimental results show that standoff detection of alpha contamination is a viable tool in radiation threat detection. Furthermore, the radioluminescence spectrum in the air is spectrally analyzed. Possibilities of camera-based alpha threat detection under various background lighting conditions are discussed.

  19. Radiation Engineering of Functional Biomaterials: From Smart Hydrogels to Theragnostic Nanodevices

    Energy Technology Data Exchange (ETDEWEB)

    Dispenza, C.; Spadaro, G. [Dipartimento di Ingegneria Chimica dei Processi e dei Materiali (DICPM), Centro Interdipartimentale di Biotecnologie Applicate (CIBA), Università degli Studi di Palermo, Palermo (Italy); Alessi, S. [Dipartimento di Ingegneria Chimica dei Processi e dei Materiali (DICPM), Università degli Studi di Palermo, Palermo (Italy)

    2009-07-01

    Radiation engineering represents an important tool in “nanobiotechology”. The possibility of manipulating photons and electrons alongside the possibility of manipulating macromolecules and biomolecules offers to the scientist and technologist an irresistible convergence of experimental tools for the generation of new or improved functional biomaterials. The versatility and the untapped potential of this approach may contribute in understanding, developing and exploring the role of nanobiomaterials in emerging research fields, such as biomolecules detection and/or delivery. In this short review, after an introductory part that describe the motivation of this research, we present some of the approaches we developed in the recent years for the synthesis and characterization of smart hydrogels for controlled delivery of proteins and for radiation engineering of nanostructured hydrogels that possess electrochemical activity and some novel optical properties. (author)

  20. Radiation Engineering of Functional Biomaterials: From Smart Hydrogels to Theragnostic Nanodevices

    International Nuclear Information System (INIS)

    Dispenza, C.; Spadaro, G.; Alessi, S.

    2009-01-01

    Radiation engineering represents an important tool in “nanobiotechology”. The possibility of manipulating photons and electrons alongside the possibility of manipulating macromolecules and biomolecules offers to the scientist and technologist an irresistible convergence of experimental tools for the generation of new or improved functional biomaterials. The versatility and the untapped potential of this approach may contribute in understanding, developing and exploring the role of nanobiomaterials in emerging research fields, such as biomolecules detection and/or delivery. In this short review, after an introductory part that describe the motivation of this research, we present some of the approaches we developed in the recent years for the synthesis and characterization of smart hydrogels for controlled delivery of proteins and for radiation engineering of nanostructured hydrogels that possess electrochemical activity and some novel optical properties. (author)

  1. Radiation-induced brain structural and functional abnormalities in presymptomatic phase and outcome prediction.

    Science.gov (United States)

    Ding, Zhongxiang; Zhang, Han; Lv, Xiao-Fei; Xie, Fei; Liu, Lizhi; Qiu, Shijun; Li, Li; Shen, Dinggang

    2018-01-01

    Radiation therapy, a major method of treatment for brain cancer, may cause severe brain injuries after many years. We used a rare and unique cohort of nasopharyngeal carcinoma patients with normal-appearing brains to study possible early irradiation injury in its presymptomatic phase before severe, irreversible necrosis happens. The aim is to detect any structural or functional imaging biomarker that is sensitive to early irradiation injury, and to understand the recovery and progression of irradiation injury that can shed light on outcome prediction for early clinical intervention. We found an acute increase in local brain activity that is followed by extensive reductions in such activity in the temporal lobe and significant loss of functional connectivity in a distributed, large-scale, high-level cognitive function-related brain network. Intriguingly, these radiosensitive functional alterations were found to be fully or partially recoverable. In contrast, progressive late disruptions to the integrity of the related far-end white matter structure began to be significant after one year. Importantly, early increased local brain functional activity was predictive of severe later temporal lobe necrosis. Based on these findings, we proposed a dynamic, multifactorial model for radiation injury and another preventive model for timely clinical intervention. Hum Brain Mapp 39:407-427, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  2. CaSO4: Dy + Teflon dosimetric pellets for X, beta and gamma radiation detection

    International Nuclear Information System (INIS)

    Campos, L.L.; Lima, M.F.

    1987-08-01

    CaSO 4 : Dy + TEFLON dosimetric pellets with high sensitivity and low cost for X, beta and gamma radiation monitoring were studied and developed by the Dosimetric Material Production Laboratory of the Radiological Protection Departament and are disposable for sale. The thickness of the pellets are suitable for X, beta and gamma radiation measurements. The dosimetric properties of these pellets were determined and presented in this work. The results show the usefulness of 0,20mm thick pellets for beta radiation monitoring and 0,80mm thick pellets for x and gamma radiation detection. (Author) [pt

  3. Analysis of reproductive function in persons exposed to chronic radiation

    International Nuclear Information System (INIS)

    Kossenko, M.M.; Ostroumova, E.V.; Vyushkova, O.V.

    2000-01-01

    The purpose of the study was to analyze the reproductive function in individuals exposed to radiation in the riverside villages on the Techa in the Southern Urals. The exposure of the population, numbering 28000, occurred in 1950-1956 as a result of discharges into the river of radioactive wastes from the Mayak facility for processing weapon plutonium. The residents were exposed to chronic radiation, both external and internal. The range of exposure doses to gonads was sufficiently wide: 20-1270 mSv. However, the distribution of doses among the exposed individuals was ununiform, and the proportion of people whose dose was below 120 mGy accounted for 74%. The following characteristics of exposed women were analyzed: menstrual function, outcomes of pregnancy, birth rates, health status for newborns. The analysis of the menstrual function in exposed women showed that in persons exposed in childhood, menarche was registered at the age of 14.3 years, on the average (based on literature sources, menarche is attained at the age of 13 for unexposed population). The mean age at menopause was 47.9 years for exposed women (the respective mean value for Russia is 50.8 years). Pregnancy outcomes were analyzed in 9000 exposed women. The rate of medical and criminal abortions was estimated as 79 per 100 labors. The rate of spontaneous abortions for exposed women was slightly higher, 3.11%, than for controls, 2.30%; these difference, however, were statistically insignificant. The total loss of fetus or neonate (unfavorable outcomes of pregnancy: spontaneous abortions, stillbirths, early neonatal death) was estimated to be 4.58% at zero dose. Exposure to gonads at the dose 1 Sv, estimated using the above-indicated method, yielded 3% of additional unfavorable outcomes of pregnancy. It was shown, based on the analysis of birth rates for the Techa Cohort that they had not undergone any essential changes over the first 25 years of exposure compared to the respective coefficients for

  4. Analysis of reproductive function in persons exposed to chronic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kossenko, M.M.; Ostroumova, E.V.; Vyushkova, O.V. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation)

    2000-05-01

    The purpose of the study was to analyze the reproductive function in individuals exposed to radiation in the riverside villages on the Techa in the Southern Urals. The exposure of the population, numbering 28000, occurred in 1950-1956 as a result of discharges into the river of radioactive wastes from the Mayak facility for processing weapon plutonium. The residents were exposed to chronic radiation, both external and internal. The range of exposure doses to gonads was sufficiently wide: 20-1270 mSv. However, the distribution of doses among the exposed individuals was ununiform, and the proportion of people whose dose was below 120 mGy accounted for 74%. The following characteristics of exposed women were analyzed: menstrual function, outcomes of pregnancy, birth rates, health status for newborns. The analysis of the menstrual function in exposed women showed that in persons exposed in childhood, menarche was registered at the age of 14.3 years, on the average (based on literature sources, menarche is attained at the age of 13 for unexposed population). The mean age at menopause was 47.9 years for exposed women (the respective mean value for Russia is 50.8 years). Pregnancy outcomes were analyzed in 9000 exposed women. The rate of medical and criminal abortions was estimated as 79 per 100 labors. The rate of spontaneous abortions for exposed women was slightly higher, 3.11%, than for controls, 2.30%; these difference, however, were statistically insignificant. The total loss of fetus or neonate (unfavorable outcomes of pregnancy: spontaneous abortions, stillbirths, early neonatal death) was estimated to be 4.58% at zero dose. Exposure to gonads at the dose 1 Sv, estimated using the above-indicated method, yielded 3% of additional unfavorable outcomes of pregnancy. It was shown, based on the analysis of birth rates for the Techa Cohort that they had not undergone any essential changes over the first 25 years of exposure compared to the respective coefficients for

  5. Apparatus for detecting alpha radiation in difficult access areas

    International Nuclear Information System (INIS)

    Steadman, P.; MacArthur, D.W.

    1997-01-01

    An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure is disclosed. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure. 4 figs

  6. Electron cascades in sensors for optical detection of ionizing radiation

    International Nuclear Information System (INIS)

    London, Richard A.; Lowry, Mark E.; Vernon, Stephen P.; Stewart, Richard E.

    2013-01-01

    A new class of high-speed detectors, called RadOptic detectors, measures ionizing radiation incident on a transparent semiconductor by sensing changes in the refractive index with an optical probe beam. We describe the role of radiation-initiated electron cascades in setting the sensitivity and the spatial and temporal resolution of RadOptic detectors. We model electron cascades with both analytical and Monte Carlo computational methods. We find that the timescale for the development of an electron cascade is less than of order 100 fs and is not expected to affect the time response of a detector. The characteristic size of the electron cloud is typically less than 2 μm, enabling high spatial resolution in imaging systems. The electron-hole pair density created by single x-rays is much smaller than the saturation density and, therefore, single events should not saturate the detector

  7. InP based semioconductor structures for radiation detection

    Czech Academy of Sciences Publication Activity Database

    Procházková, Olga; Grym, Jan; Pekárek, Ladislav; Zavadil, Jiří; Žďánský, Karel

    2008-01-01

    Roč. 19, 8/9 (2008), s. 700-775 ISSN 0957-4522. [Semiconducting & Insulating Materials Conference - SIMC /14./. Fayetteville, 15.05.2007-20.05.2007] R&D Projects: GA ČR GA102/06/0153 Institutional research plan: CEZ:AV0Z20670512 Keywords : semiconductor technology * rare earth compounds * radiation detectors Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.054, year: 2008

  8. Track structure theory in radiobiology and in radiation detection

    International Nuclear Information System (INIS)

    Katz, R.

    1976-01-01

    The response of biological cells, and many physical radiation and track detectors to ionizing radiations, and to energetic heavily ionizing particles results from the secondary and higher generation electrons ejected from the atoms and molecules of the detector by the incident primary radiation. The models which have been used for detector response arise from target theory, and are of the form of statistical models called multi-hit or multi-target detectors, in which it is assumed that there are sensitive elements (emulsion grains, or biological cell nuclei) which may require many hits (emulsion grains) or single hits in different targets (say, cellular chromosomes) in order to produce the observed endpoint. Physically, a hit is interpreted as a 'registered event' caused by an electron passing through the sensitive site, with an efficiency which depends on the electron's speed. Some knowledge of size of the sensitive volume and of the sensitive target is required to make the transition from gamma-ray response to heavy ion response. Recent work has demonstrated that many-hit physical detectors do exist. From both emulsion sensitometry and from the structure of tracks of heavy ions, we are able to show that emulsion-developer combinations exist which yield many-hit response. There is also some evidence that the supralinearity in thermoluminescent dosimeters arises from a trap structures within the same TLD crystal. These detectors can be expected to mimic the response of biological cells to radiations of different quality. Their patterns of response may help us to understand better the structure of particle tracks in SSNTD's. (orig./ORU) [de

  9. Co-TPP functionalized carbon nanotube composites for detection of ...

    Indian Academy of Sciences (India)

    and real-time monitoring devices.13 Out of various kinds ... MWNT for some gases operating at sensor temperatures of ... (M-Pc) functionalized MWNT for detection of H2O2 in the .... macrocyclic systems and p-type semiconductors while the.

  10. Silver-functionalized carbon nanofiber composite electrodes for ibuprofen detection

    NARCIS (Netherlands)

    Manea, F.; Motoc, S.; Pop, A.; Remes, A.; Schoonman, J.

    2012-01-01

    The aim of this study is to prepare and characterize two types of silver-functionalized carbon nanofiber (CNF) composite electrodes, i.e., silver-decorated CNF-epoxy and silver-modified natural zeolite-CNF-epoxy composite electrodes suitable for ibuprofen detection in aqueous solution. Ag carbon

  11. UTILIZATION OF PHOSWICH DETECTORS FOR SIMULTANEOUS, MULTIPLE RADIATION DETECTION

    International Nuclear Information System (INIS)

    Miller, William H.; Manuel Diaz de Leon

    2003-01-01

    A phoswich radiation detector is comprised of a phosphor sandwich in which several different phosphors are viewed by a common photomultiplier. By selecting the appropriate phosphors, this system can be used to simultaneously measure multiple radiation types (alpha, beta, gamma and/or neutron) with a single detector. Differentiation between the signals from the different phosphors is accomplished using digital pulse shape discrimination techniques. This method has been shown to result in accurate discrimination with highly reliable and versatile digital systems. This system also requires minimal component count (i.e. only the detector and a computer for signal processing). A variety of detectors of this type have been built and tested including: (1) a triple phoswich system for alpha/beta/gamma swipe counting, (2) two well-type detectors for measuring low levels of low energy photons in the presence of a high energy background, (3) a large area detector for measuring beta contamination in the presence of a photon background, (4) another large area detector for measuring low energy photons from radioactive elements such as uranium in the presence of a photon background. An annular geometry, triple phoswich system optimized for measuring alpha/beta/gamma radiation in liquid waste processing streams is currently being designed

  12. UTILIZATION OF PHOSWICH DETECTORS FOR SIMULTANEOUS, MULTIPLE RADIATION DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    William H. Miller; Manuel Diaz de Leon

    2003-04-15

    A phoswich radiation detector is comprised of a phosphor sandwich in which several different phosphors are viewed by a common photomultiplier. By selecting the appropriate phosphors, this system can be used to simultaneously measure multiple radiation types (alpha, beta, gamma and/or neutron) with a single detector. Differentiation between the signals from the different phosphors is accomplished using digital pulse shape discrimination techniques. This method has been shown to result in accurate discrimination with highly reliable and versatile digital systems. This system also requires minimal component count (i.e. only the detector and a computer for signal processing). A variety of detectors of this type have been built and tested including: (1) a triple phoswich system for alpha/beta/gamma swipe counting, (2) two well-type detectors for measuring low levels of low energy photons in the presence of a high energy background, (3) a large area detector for measuring beta contamination in the presence of a photon background, (4) another large area detector for measuring low energy photons from radioactive elements such as uranium in the presence of a photon background. An annular geometry, triple phoswich system optimized for measuring alpha/beta/gamma radiation in liquid waste processing streams is currently being designed.

  13. Transfer function and near-field detection of evanescent waves

    DEFF Research Database (Denmark)

    Radko, Ylia P.; Bozhevolnyi, Sergey I.; Gregersen, Niels

    2006-01-01

    of collection and illumination modes. Making use of a collection near-field microscope with a similar fiber tip illuminated by an evanescent field, we measure the collected power as a function of the field spatial frequency in different polarization configurations. Considering a two-dimensional probe...... for the transfer function, which is derived by introducing an effective pointof (dipolelike) detection inside the probe tip. It is found to be possible to fit reasonably well both the experimental and the simulation data for evanescent field components, implying that the developed approximation of the near......-field transfer function can serve as a simple, rational, and sufficiently reliable means of fiber probe characterization....

  14. System and method for extracting physiological information from remotely detected electromagnetic radiation

    NARCIS (Netherlands)

    2016-01-01

    The present invention relates to a device and a method for extracting physiological information indicative of at least one health symptom from remotely detected electromagnetic radiation. The device comprises an interface (20) for receiving a data stream comprising remotely detected image data

  15. System and method for extracting physiological information from remotely detected electromagnetic radiation

    NARCIS (Netherlands)

    2015-01-01

    The present invention relates to a device and a method for extracting physiological information indicative of at least one health symptom from remotely detected electromagnetic radiation. The device comprises an interface (20) for receiving a data stream comprising remotely detected image data

  16. AN IMAGE-ANALYSIS TECHNIQUE FOR DETECTION OF RADIATION-INDUCED DNA FRAGMENTATION AFTER CHEF ELECTROPHORESIS

    NARCIS (Netherlands)

    ROSEMANN, M; KANON, B; KONINGS, AWT; KAMPINGA, HH

    CHEF-electrophoresis was used as a technique to detect radiation-induced DNA breakage with special emphasis to biological relevant X-ray doses (0-10 Gy). Fluorescence detection of DNA-fragments using a sensitive image analysis system was directly compared with conventional scintillation counting of

  17. High LET radiation shows no major cellular and functional effects on primary cardiomyocytes in vitro

    Science.gov (United States)

    Heselich, Anja; Frieß, Johannes L.; Ritter, Sylvia; Benz, Naja P.; Layer, Paul G.; Thielemann, Christiane

    2018-02-01

    It is well known that ionizing radiation causes adverse effects on various mammalian tissues. However, there is little information on the biological effects of heavy ion radiation on the heart. In order to fill this gap, we systematically examined DNA-damage induction and repair, as well as proliferation and apoptosis in avian cardiomyocyte cultures irradiated with heavy ions such as titanium and iron, relevant for manned space-flight, and carbon ions, as used for radiotherapy. Further, and to our knowledge for the first time, we analyzed the effect of heavy ion radiation on the electrophysiology of primary cardiomyocytes derived from chicken embryos using the non-invasive microelectrode array (MEA) technology. As electrophysiological endpoints beat rate and field action potential duration were analyzed. The cultures clearly exhibited the capacity to repair induced DNA damage almost completely within 24 h, even at doses of 7 Gy, and almost completely recovered from radiation-induced changes in proliferative behavior. Interestingly, no significant effects on apoptosis could be detected. Especially the functionality of primary cardiac cells exhibited a surprisingly high robustness against heavy ion radiation, even at doses of up to 7 Gy. In contrast to our previous study with X-rays the beat rate remained more or less unaffected after heavy ion radiation, independently of beam quality. The only change we could observe was an increase of the field action potential duration of up to 30% after titanium irradiation, diminishing within the following three days. This potentially pathological observation may be an indication that heavy ion irradiation at high doses could bear a long-term risk for cardiovascular disease induction.

  18. Speech/Nonspeech Detection Using Minimal Walsh Basis Functions

    Directory of Open Access Journals (Sweden)

    Pwint Moe

    2007-01-01

    Full Text Available This paper presents a new method to detect speech/nonspeech components of a given noisy signal. Employing the combination of binary Walsh basis functions and an analysis-synthesis scheme, the original noisy speech signal is modified first. From the modified signals, the speech components are distinguished from the nonspeech components by using a simple decision scheme. Minimal number of Walsh basis functions to be applied is determined using singular value decomposition (SVD. The main advantages of the proposed method are low computational complexity, less parameters to be adjusted, and simple implementation. It is observed that the use of Walsh basis functions makes the proposed algorithm efficiently applicable in real-world situations where processing time is crucial. Simulation results indicate that the proposed algorithm achieves high-speech and nonspeech detection rates while maintaining a low error rate for different noisy conditions.

  19. Detection of radiation induced lung injury in rats using dynamic hyperpolarized 129Xe magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Fox, Matthew S.; Ouriadov, Alexei; Hegarty, Elaine; Thind, Kundan; Wong, Eugene; Hope, Andrew; Santyr, Giles E.

    2014-01-01

    .6 ± 9.6 ms) that were not significantly different from baseline. Conclusions: Whole-lung tissue transfer time constants for 129 Xe (T Tr-tissue ) can be used to detect the early phase of RILI in a rat model involving 14 Gy thoracic 60 Co exposure as early as two weeks post-irradiation. This knowledge combined with more sophisticated models of gas exchange and imaging techniques, may allow functional lung avoidance radiation therapy planning to be achievable, providing more beneficial treatment plans and improved quality of life for recovering lung cancer patients

  20. Simulation and modeling for the stand-off radiation detection system (SORDS) using GEANT4

    Energy Technology Data Exchange (ETDEWEB)

    Hoover, Andrew S [Los Alamos National Laboratory; Wallace, Mark [Los Alamos National Laboratory; Galassi, Mark [Los Alamos National Laboratory; Mocko, Michal [Los Alamos National Laboratory; Palmer, David [Los Alamos National Laboratory; Schultz, Larry [Los Alamos National Laboratory; Tornga, Shawn [Los Alamos National Laboratory

    2009-01-01

    A Stand-Off Radiation Detection System (SORDS) is being developed through a joint effort by Raytheon, Los Alamos National Laboratory, Bubble Technology Industries, Radiation Monitoring Devices, and the Massachusetts Institute of Technology, for the Domestic Nuclear Detection Office (DNDO). The system is a mobile truck-based platform performing detection, imaging, and spectroscopic identification of gamma-ray sources. A Tri-Modal Imaging (TMI) approach combines active-mask coded aperture imaging, Compton imaging, and shadow imaging techniques. Monte Carlo simulation and modeling using the GEANT4 toolkit was used to generate realistic data for the development of imaging algorithms and associated software code.

  1. Statistical study of undulator radiated power by a classical detection system in the mm-wave regime

    Directory of Open Access Journals (Sweden)

    A. Eliran

    2009-05-01

    Full Text Available The statistics of FEL spontaneous emission power detected with a detector integration time much larger than the slippage time has been measured in many previous works at high frequencies. In such cases the quantum (shot noise generated in the detection process is dominant. We have measured spontaneous emission in the Israeli electrostatic accelerator FEL (EA-FEL operating in the mm-wave lengths. In this regime the detector is based on a diode rectifier for which the detector quantum noise is negligible. The measurements were repeated numerous times in order to create a sample space with sufficient data enabling evaluation of the statistical features of the radiated power. The probability density function of the radiated power was found and its moments were calculated. The results of analytical and numerical models are compared to those obtained in experimental measurements.

  2. Study and characterization of the III-V semiconductor materials for applications in the detection of ionizing radiation

    International Nuclear Information System (INIS)

    Moulin, H.

    1989-11-01

    The photoconduction in the bulk of the gallium arsenide (GaAs) and of the indium phosphide doped with iron (InP:Fe) is investigated. These compounds are to be applied in devices for X-ray detection. In such semiconductor materials the detection of X-rays occurs in the bulk. The photoconduction theory and the characteristics of the materials are reviewed. Two computerized simulation models for studying the response of the photoconductors to the radiation pulses are described. The results concerning the following measurements are presented: the characterization of GaAs and InP:Fe photoconductors, in obscurity, as a function of the electric field of polarization and of the neutrons dose; and their characterization under X-ray radiation [fr

  3. Technical specifications manual for the MARK-1 pulsed ionizing radiation detection system

    International Nuclear Information System (INIS)

    Lawrence, R.S.; Harker, Y.D.; Jones, J.L.; Hoggan, J.M.

    1993-03-01

    The MARK-1 detection system was developed by the Idaho National Engineering Laboratory for the US Department of Energy Office of Arms Control and Nonproliferation. The completely portable system was designed for the detection and analysis of intense photon emissions from pulsed ionizing radiation sources. This manual presents the technical design specifications for the MARK-1 detection system and was written primarily to assist the support or service technician in the service, calibration, and repair of the system. The manual presents the general detection system theory, the MARK-1 component design specifications, the acquisition and control software, the data processing sequence, and the system calibration procedure. A second manual entitled: Volume 2: Operations Manual for the MARK-1 Pulsed Ionizing Radiation Detection System (USDOE Report WINCO-1108, September 1992) provides a general operational description of the MARK-1 detection system. The Operations Manual was written primarily to assist the field operator in system operations and analysis of the data

  4. Technical specifications manual for the MARK-1 pulsed ionizing radiation detection system. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, R.S.; Harker, Y.D.; Jones, J.L.; Hoggan, J.M.

    1993-03-01

    The MARK-1 detection system was developed by the Idaho National Engineering Laboratory for the US Department of Energy Office of Arms Control and Nonproliferation. The completely portable system was designed for the detection and analysis of intense photon emissions from pulsed ionizing radiation sources. This manual presents the technical design specifications for the MARK-1 detection system and was written primarily to assist the support or service technician in the service, calibration, and repair of the system. The manual presents the general detection system theory, the MARK-1 component design specifications, the acquisition and control software, the data processing sequence, and the system calibration procedure. A second manual entitled: Volume 2: Operations Manual for the MARK-1 Pulsed Ionizing Radiation Detection System (USDOE Report WINCO-1108, September 1992) provides a general operational description of the MARK-1 detection system. The Operations Manual was written primarily to assist the field operator in system operations and analysis of the data.

  5. Direct detection of darkmatter in radiative seesaw model

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Daniel; Schwetz, Thomas [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Toma, Takashi [Institute for Theoretical Physics, Kanazawa University (Japan)

    2012-07-01

    In the radiative seesaw model proposed by Ma, we assume that the lightest right-handed neutrino is the Dark Matter candidate and almost degenerated with the second lightest right-handed neutrino. Thus, elastic Dark Matter-nucleus scattering is suppressed. Inelastic scattering is induced by a lepton-loop coupled to the photon. Effectively, there are charge-charge, dipole-charge and dipole-dipole interactions. We present the event rate of the model and compare it with existing data. Moreover, monochromatic photons from the decay of the excited Dark Matter state are discussed.

  6. Should regional ventilation function be considered during radiation treatment planning to prevent radiation-induced complications?

    Energy Technology Data Exchange (ETDEWEB)

    Lan, Fujun; Jeudy, Jean; D’Souza, Warren; Tseng, Huan-Hsin; Zhou, Jinghao; Zhang, Hao, E-mail: haozhang@som.umaryland.edu [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland 21201 (United States); Senan, Suresh; Sornsen de Koste, J. R. van [Department of Radiation Oncology, VU University Medical Center, P.O. Box 7057, Amsterdam 1007 MB (Netherlands)

    2016-09-15

    Purpose: To investigate the incorporation of pretherapy regional ventilation function in predicting radiation fibrosis (RF) in stage III nonsmall cell lung cancer (NSCLC) patients treated with concurrent thoracic chemoradiotherapy. Methods: Thirty-seven patients with stage III NSCLC were retrospectively studied. Patients received one cycle of cisplatin–gemcitabine, followed by two to three cycles of cisplatin–etoposide concurrently with involved-field thoracic radiotherapy (46–66 Gy; 2 Gy/fraction). Pretherapy regional ventilation images of the lung were derived from 4D computed tomography via a density change–based algorithm with mass correction. In addition to the conventional dose–volume metrics (V{sub 20}, V{sub 30}, V{sub 40}, and mean lung dose), dose–function metrics (fV{sub 20}, fV{sub 30}, fV{sub 40}, and functional mean lung dose) were generated by combining regional ventilation and radiation dose. A new class of metrics was derived and referred to as dose–subvolume metrics (sV{sub 20}, sV{sub 30}, sV{sub 40}, and subvolume mean lung dose); these were defined as the conventional dose–volume metrics computed on the functional lung. Area under the receiver operating characteristic curve (AUC) values and logistic regression analyses were used to evaluate these metrics in predicting hallmark characteristics of RF (lung consolidation, volume loss, and airway dilation). Results: AUC values for the dose–volume metrics in predicting lung consolidation, volume loss, and airway dilation were 0.65–0.69, 0.57–0.70, and 0.69–0.76, respectively. The respective ranges for dose–function metrics were 0.63–0.66, 0.61–0.71, and 0.72–0.80 and for dose–subvolume metrics were 0.50–0.65, 0.65–0.75, and 0.73–0.85. Using an AUC value = 0.70 as cutoff value suggested that at least one of each type of metrics (dose–volume, dose–function, dose–subvolume) was predictive for volume loss and airway dilation, whereas lung consolidation

  7. Probability of detection as a function of multiple influencing parameters

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovic, Mato

    2014-10-15

    Non-destructive testing is subject to measurement uncertainties. In safety critical applications the reliability assessment of its capability to detect flaws is therefore necessary. In most applications, the flaw size is the single most important parameter that influences the probability of detection (POD) of the flaw. That is why the POD is typically calculated and expressed as a function of the flaw size. The capability of the inspection system to detect flaws is established by comparing the size of reliably detected flaw with the size of the flaw that is critical for the structural integrity. Applications where several factors have an important influence on the POD are investigated in this dissertation. To devise a reliable estimation of the NDT system capability it is necessary to express the POD as a function of all these factors. A multi-parameter POD model is developed. It enables POD to be calculated and expressed as a function of several influencing parameters. The model was tested on the data from the ultrasonic inspection of copper and cast iron components with artificial flaws. Also, a technique to spatially present POD data called the volume POD is developed. The fusion of the POD data coming from multiple inspections of the same component with different sensors is performed to reach the overall POD of the inspection system.

  8. Probability of detection as a function of multiple influencing parameters

    International Nuclear Information System (INIS)

    Pavlovic, Mato

    2014-01-01

    Non-destructive testing is subject to measurement uncertainties. In safety critical applications the reliability assessment of its capability to detect flaws is therefore necessary. In most applications, the flaw size is the single most important parameter that influences the probability of detection (POD) of the flaw. That is why the POD is typically calculated and expressed as a function of the flaw size. The capability of the inspection system to detect flaws is established by comparing the size of reliably detected flaw with the size of the flaw that is critical for the structural integrity. Applications where several factors have an important influence on the POD are investigated in this dissertation. To devise a reliable estimation of the NDT system capability it is necessary to express the POD as a function of all these factors. A multi-parameter POD model is developed. It enables POD to be calculated and expressed as a function of several influencing parameters. The model was tested on the data from the ultrasonic inspection of copper and cast iron components with artificial flaws. Also, a technique to spatially present POD data called the volume POD is developed. The fusion of the POD data coming from multiple inspections of the same component with different sensors is performed to reach the overall POD of the inspection system.

  9. Preparation of functionalized carbon nanotubes using radiation technique

    International Nuclear Information System (INIS)

    Chen Shimou; Wu Guozhong; Huang Shirong; Zhu Guanglai

    2006-01-01

    Carbon nanotubes (CNTs) have attracted great interest because of their unique structural, electronic, mechanical, and optical properties. However, the studies and applications of CNTs are hindered by processing and manipulation difficulties owing to their insolubility or poor dispersion in common solvents and polymeric matrixes. To facilitate their applications, many approaches were employed to functionalize CNTs with functional groups, either noncovalently or covalently. In our study, radiation technique was utilized to produce functionalized CNTs. In a typical experiment, multiwalled carbon nanotubes (MWNTs) were irradiated in potassium persulfate aqueous solution. Persulfnic group can react with hydrated electrons to produce sulfuric acid radicals, which can attack the c=c on the surface of tubes to form sulfonated MWNTs. On the other hand, grafting polymer (instead of low-molecular-weight compound) onto CNTs by an appropriate method is a possible strategy for preparing the nanotubes with little damage in structure and high solubility in solvent. A facile strategy to prepare water soluble MWNTs in large scale by two steps of gamma irradiation has been developed at SINAP. The first step is to irradiate MWNTs in ethanol. The radiolysis of ethanol produced many active species such as . CH 2 CH 2 OH, CH 3 . CHCH 2 OH, which react with C=C of MWNTs and attach onto the surface of MWNTs. Then, poly(acrylic acid) was covalently grafted to the surface of MWNTs by irradiating the samples in the presence of acrylic acid. The PAA-grafted MWNTs have good solubility in water and other polar solvents. This two-step grafting approach may also be of help for introducing other functional polymer chains onto MWNTs. (authors)

  10. Development of mobile radiation detection system against nuclear terrorism in Korea

    International Nuclear Information System (INIS)

    Kwak, Sung-Woo; Chang, Sung-Soon; Yoo, Ho-Sik

    2011-01-01

    A fixed radiation portal monitors (RPM) deployed at border, seaport, airport or key traffic checkpoints has played an important role in preventing the illicit trafficking and transport of nuclear and radioactive materials. However, the RPM usually is large and heavy and can't easily be moved to a different location. An intelligent terrorist may also circumvent the fixed RPM to avoid being detected. These reasons motivate us to develop a mobile radiation detection system. The objective of this paper is to report our experience on developing the mobile radiation detection system for the search and detection of nuclear and radioactive materials during road transport. Measurements were performed at various speeds and distances between the radioactive isotope (RI) transporting car and the measurement car. Results of our measurements and the detection limits of the system is described in this paper. The mobile radiation detection system developed should contribute to defending public's health and safety and the environment against nuclear and radiological terrorism by detecting nuclear or radioactive material hidden illegally in a vehicle. (author)

  11. Large single-crystal diamond substrates for ionizing radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Girolami, Marco; Bellucci, Alessandro; Calvani, Paolo; Trucchi, Daniele M. [Istituto di Struttura della Materia (ISM), Consiglio Nazionale delle Ricerche (CNR), Sede Secondaria di Montelibretti, Monterotondo Stazione, Roma (Italy)

    2016-10-15

    The need for large active volume detectors for ionizing radiations and particles, with both large area and thickness, is becoming more and more compelling in a wide range of applications, spanning from X-ray dosimetry to neutron spectroscopy. Recently, 8.0 x 8.0 mm{sup 2} wide and 1.2 mm thick single-crystal diamond plates have been put on the market, representing a first step to the fabrication of large area monolithic diamond detectors with optimized charge transport properties, obtainable up to now only with smaller samples. The more-than-double thickness, if compared to standard plates (typically 500 μm thick), demonstrated to be effective in improving the detector response to highly penetrating ionizing radiations, such as γ-rays. Here we report on the first measurements performed on large active volume single-crystal diamond plates, both in the dark and under irradiation with optical wavelengths (190-1100 nm), X-rays, and radioactive γ-emitting sources ({sup 57}Co and {sup 22}Na). (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Detection of some irradiated spices on the basis of radiation induced damage of starch

    International Nuclear Information System (INIS)

    Farkas, J.; Sharif, M.M.; Koncz, A.

    1990-01-01

    Untreated and irradiated samples of spices were suspended in water, alkalized, and after heat-gelatinization, the apparent viscosity was determined by a rotational viscometer. Several spices, i.e. white pepper, black pepper, nutmeg and ginger showed considerable loss of viscosity as a function of γ radiation dose in the dose range required for microbial decontamination of natural spices. Less promising results were obtained with spices such as allspice, garlic powder, and onion powder forming low-viscosity heat-treated suspensions even when unirradiated viscometric studies were also performed with a number of pepper samples of various origin to estimate the ''natural'' variation of rheological properties. Irradiation and storage studies were performed with ground black pepper samples of moisture contents in equilibrium with air of 25%, 50% and 75% R.H., respectively, either untreated or irradiated with 4, 8, 16 or 32 kGy, to study the effect of equilibrium relative humidity and storage time on detectability of radiation treatment. During the entire storage period of 100 days, statistically significant differences of the apparent viscosities of heat-gelatinized suspensions remained detectable between untreated samples and those irradiated with 8 kGy or higher doses. The apparent viscosity of high-moisture (75% E.R.H.) untreated samples was decreasing during long-term storage. Differences between viscosities of untreated and irradiated samples were enlarged when measured at elevated temperatures such as 50 0 C in the rotational viscometer, or in the boiling-water bath of a falling number apparatus. Other analytical indices such as onset and peak temperatures of gelatinization endotherms by DSC (damaged starch content), by colorimetry, reducing sugar content, alcohol-induced turbidity of hot water extracts of pepper samples, have been changed less dramatically by irradiation than the apparent viscosity of the gelatinized suspensions. (author)

  13. Detection of radiation-induced apoptosis using the comet assay

    International Nuclear Information System (INIS)

    Wada, Seiichi; Kobayashi, Yasuhiko; Funayama, Tomoo; Yamamoto, Kazuo; Khoa, Tran Van; Natsuhori, Masahiro; Ito, Nobuhiko

    2003-01-01

    The electrophoresis pattern of apoptotic cells detected by the comet assay has a characteristic small head and spread tail. This image has been referred to as an apoptotic comet, but it has not been previously proven to be apoptotic cells by any direct method. In order to identify this image obtained by the comet assay as corresponding to an apoptotic cell, the frequency of appearance of apoptosis was examined using CHO-K1 and L5178Y cells which were exposed to gamma irradiation. As a method for detecting apoptosis, the terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) assay was used. When the frequency of appearance of apoptotic cells following gamma irradiation was observed over a period of time, there was a significant increase in appearance of apoptosis when using the TUNEL assay. However, there was only a slight increase when using the comet assay. In order to verify the low frequency of appearance of apoptosis when using the comet assay, we attempted to use the TUNEL assay to satin the apoptotic comets detected in the comet assay. The apoptotic comets were TUNEL positive and the normal comets were TUNEL negative. This indicates that the apoptotic comets were formed from DNA fragments with 3'-hydroxy ends that are generated as cells undergo apoptosis. Therefore, it was understood that the characteristic pattern of apoptotic comets detected by the comet assay corresponds to cells undergoing apoptosis. (author)

  14. Analysis of Scattered Radiation Influence on Detectability in Diagnostic Radiology

    Energy Technology Data Exchange (ETDEWEB)

    Gurvich, V [ALVIM R and D Ltd., P.O.B. 801 Jerusalem 91007 (Israel); Manevich, I [Jerusalem College of Technology, 21 Havaad Haleumi St. P.O.B. 16031, Jerusalem 91160 (Israel)

    1994-12-31

    The calculation of holes detectability in tissue equivalent materials on a X-ray image is implemented. In the calculation various values of scatter accumulation factor are used. The obtained results confirmed by experimental data may be useful for choice of physics-technical conditions of X-ray examination. (authors). 7 refs, 1 fig, 1 tab.

  15. Plasma functionalized surface of commodity polymers for dopamine detection

    Energy Technology Data Exchange (ETDEWEB)

    Fabregat, Georgina [Departament d’Enginyeria Química, E.T.S. d’Enginyeria Industrial de Barcelona, Universitat Politècnica de Catalunya, Diagonal 647, 08028, Barcelona (Spain); Center for Research in Nano-Engineering, Universitat Politècnica de Catalunya, Campus Sud, Edifici C’, C/Pasqual i Vila s/n, Barcelona, E-08028 (Spain); Osorio, Joaquin [Departament d’Enginyeria Química, E.T.S. d’Enginyeria Industrial de Barcelona, Universitat Politècnica de Catalunya, Diagonal 647, 08028, Barcelona (Spain); Castedo, Alejandra [Center for Research in Nano-Engineering, Universitat Politècnica de Catalunya, Campus Sud, Edifici C’, C/Pasqual i Vila s/n, Barcelona, E-08028 (Spain); Institut de Tècniques Energètiques, E.T.S. d’Enginyeria Industrial de Barcelona, Universitat Politècnica de Catalunya, Diagonal 647, 08028, Barcelona (Spain); Armelin, Elaine [Departament d’Enginyeria Química, E.T.S. d’Enginyeria Industrial de Barcelona, Universitat Politècnica de Catalunya, Diagonal 647, 08028, Barcelona (Spain); Center for Research in Nano-Engineering, Universitat Politècnica de Catalunya, Campus Sud, Edifici C’, C/Pasqual i Vila s/n, Barcelona, E-08028 (Spain); and others

    2017-03-31

    Highlights: • Electrochemically inert polymers become electroactive after plasma functionalization. • Selective dopamine detection has been achieved functionalizing polymers with plasma. • Plasma-functionalized polymers are sensitive dopamine detectors. • XPS analyses reflect the transformation of inert polymers into electrosensors. - Abstract: We have fabricated potentially generalizable sensors based on polymeric-modified electrodes for the electrochemical detection of dopamine. Sensitive and selective sensors have been successfully obtained by applying a cold-plasma treatment during 1–2 min not only to conducting polymers but also to electrochemically inert polymers, such as polyethylene, polypropylene, polyvinylpyrrolidone, polycaprolactone and polystyrene. The effects of the plasma in the electrode surface activation, which is an essential requirement for the dopamine detection when inert polymers are used, have been investigated using X-ray photoelectron spectroscopy. Results indicate that exposure of polymer-modified electrodes to cold-plasma produces the formation of a large variety of reactive species adsorbed on the electrode surface, which catalyse the dopamine oxidation. With this technology, which is based on the application of a very simple physical functionalization, we have defined a paradox-based paradigm for the fabrication of electrochemical sensors by using inert and cheap plastics.

  16. An integrated circuit/microsystem/nano-enhanced four species radiation sensor for inexpensive fissionable material detection

    Science.gov (United States)

    Waguespack, Randy Paul

    2011-12-01

    Small scale radiation detectors sensitive to alpha, beta, electromagnetic, neutron radiation are needed to combat the threat of nuclear terrorism and maintain national security. There are many types of radiation detectors on the market, and the type of detector chosen is usually determined by the type of particle to be detected. In the case of fissionable material, an ideal detector needs to detect all four types of radiation, which is not the focus of many detectors. For fissionable materials, the two main types of radiation that must be detected are gamma rays and neutrons. Our detector uses a glass or quartz scintillator doped with 10B nanoparticles to detect all four types of radiation particles. Boron-10 has a thermal neutron cross section of 3,840 barns. The interaction between the neutron and boron results in a secondary charge particle in the form of an alpha particle to be emitted, which is detectable by the scintillator. Radiation impinging on the scintillator matrix produces varying optical pulses dependent on the energy of the particles. The optical pulses are then detected by a photomultiplier (PM) tube, creating a current proportional to the energy of the particle. Current pulses from the PM tube are differentiated by on-chip pulse height spectroscopy, allowing for source discrimination. The pulse height circuitry has been fabricated with discrete circuits and designed into an integrated circuit package. The ability to replace traditional PM tubes with a smaller, less expensive photomultiplier will further reduce the size of the device and enhance the cost effectiveness and portability of the detector.

  17. Simulating and Detecting Radiation-Induced Errors for Onboard Machine Learning

    Science.gov (United States)

    Wagstaff, Kiri L.; Bornstein, Benjamin; Granat, Robert; Tang, Benyang; Turmon, Michael

    2009-01-01

    Spacecraft processors and memory are subjected to high radiation doses and therefore employ radiation-hardened components. However, these components are orders of magnitude more expensive than typical desktop components, and they lag years behind in terms of speed and size. We have integrated algorithm-based fault tolerance (ABFT) methods into onboard data analysis algorithms to detect radiation-induced errors, which ultimately may permit the use of spacecraft memory that need not be fully hardened, reducing cost and increasing capability at the same time. We have also developed a lightweight software radiation simulator, BITFLIPS, that permits evaluation of error detection strategies in a controlled fashion, including the specification of the radiation rate and selective exposure of individual data structures. Using BITFLIPS, we evaluated our error detection methods when using a support vector machine to analyze data collected by the Mars Odyssey spacecraft. We found ABFT error detection for matrix multiplication is very successful, while error detection for Gaussian kernel computation still has room for improvement.

  18. Numerical methods for characterization of synchrotron radiation based on the Wigner function method

    Directory of Open Access Journals (Sweden)

    Takashi Tanaka

    2014-06-01

    Full Text Available Numerical characterization of synchrotron radiation based on the Wigner function method is explored in order to accurately evaluate the light source performance. A number of numerical methods to compute the Wigner functions for typical synchrotron radiation sources such as bending magnets, undulators and wigglers, are presented, which significantly improve the computation efficiency and reduce the total computation time. As a practical example of the numerical characterization, optimization of betatron functions to maximize the brilliance of undulator radiation is discussed.

  19. Development of Remote Control Laboratory for Radiation Detection via Internet

    International Nuclear Information System (INIS)

    Park, Sang Tae; Lee, Hee Bok; Yuk, Keun Chul

    2002-01-01

    The role of experiments in science education is essential for understanding the natural phenomena and principle related to a subject. Therefore, the remote control experiment via Internet is one of key solution for distance learners in science education. The remote experiments are also necessary for the time-consuming experiment which takes several days, collaborative experiment between distance learners, expensive laboratory equipment which is not usually available to students, experimental procedure which is dangerous, etc. In this study, we have developed a general method for a remote control laboratory system using internet and interface techniques. It is possible for students to learn the nuclear physics to control the real instruments and conduct physics experimentation with internet techniques. We proposed the remote control radiation measurement system as a sample application. This system could be useful for the monitoring near a nuclear power plants in order to improve the environment data credibility to the public

  20. Enhancing international radiation/nuclear detection training opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Thomas L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bersell, Bridget M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Booker, Paul M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Anderson, Gerald E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Leitch, Rosalyn M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Meagher, John B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Siefken, Rob R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Spracklen, James L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-23

    The United States has worked domestically to develop and provide radiological and nuclear detection training and education initiatives aimed at interior law enforcement, but the international community has predominantly focused efforts at border and customs officials. The interior law enforcement officials of a State play a critical role in maintaining an effective national-level nuclear detection architecture. To meet this vital need, DNDO was funded by the U.S. Department of State (DOS) to create and deliver a 1-week course at the International Law Enforcement Academy (ILEA) in Budapest, Hungary to inform interior law enforcement personnel of the overall mission, and to provide an understanding of how the participants can combat the threats of radiological and nuclear terrorism through detection efforts. Two courses, with approximately 20 students in each course, were delivered in fiscal year (FY) 2013, two were delivered in FY 2014 and FY 2015, and as of this report’s writing more are planned in FY 2016. However, while the ILEA courses produced measurable success, DNDO requested Pacific Northwest National Laboratory (PNNL) research potential avenues to further increase the course impact.In a multi-phased approach, PNNL researched and analyzed several possible global training locations and venues, and other possible ways to increase the impact of the course using an agreed-to data-gathering format.

  1. Detection of the strange bodies on the conveyor belt using gamma radiation technique

    International Nuclear Information System (INIS)

    Barna, A.; Ochiana, G.; Oncescu, M.

    1990-01-01

    The aim of this paper is to present a method for the computation of the activity of a gamma radiation source used in a radiometric assembly designed to detect the strange bodies (iron, stone or wood-made granules) within the textile material on the conveyor belt. The mathematical modelling method based on the Monte Carlo procedure has been used, with different values of the errors of types I and II; the investigation method is the transmission of gamma radiations. (Author)

  2. Electrical Versus Optical: Comparing Methods for Detecting Terahertz Radiation Using Neon Lamps

    Science.gov (United States)

    Slocombe, L. L.; Lewis, R. A.

    2018-05-01

    Terahertz radiation impinging on a lit neon tube causes additional ionization of the encapsulated gas. As a result, the electrical current flowing between the electrodes increases and the glow discharge in the tube brightens. These dual phenomena suggest two distinct modes of terahertz sensing. The electrical mode simply involves measuring the electrical current. The optical mode involves monitoring the brightness of the weakly ionized plasma glow discharge. Here, we directly compare the two detection modes under identical experimental conditions. We measure 0.1-THz radiation modulated at frequencies in the range 0.1-10 kHz, for lamp currents in the range 1-10 mA. We find that electrical detection provides a superior signal-to-noise ratio while optical detection has a faster response. Either method serves as the basis of a compact, robust, and inexpensive room-temperature detector of terahertz radiation.

  3. Retinal, optic nerve and chiasmal function following radiation therapy demonstrated by visual evoked response testing

    International Nuclear Information System (INIS)

    Soni, A.B.; Constine, L.S.; Smith, D.; Palisca, M.; Ojomo, K.; Muhs, A.

    1997-01-01

    Purpose: To evaluate the tolerance of the retina, optic nerve, and optic chiasm to radiation doses conventionally used to treat patients with primary brain or pituitary tumors and to explore the character of detectable radiation effects. Visual evoked response (VER) testing is a noninvasive and sensitive method for identifying radiation injury to the visual system due to alterations in small vessel or myelin integrity. Such evaluations may increase our understanding of the threshold for and the pathogenesis of radiation injury. Materials and Methods: Twenty-four patients irradiated for brain or pituitary tumors between 1972 and 1996 had VER testing. Patients were included in study if the retina, optic nerves or chiasm were in the radiation (RT) field. At the time of RT patients ranged in age from 1.5 to 55 years (median 33). Mean doses were as follows: right retina, 29 Gy (range 10 - 60 Gy); left retina, 29.5 Gy (range 10 - 60 Gy); right optic nerve, 42.9 Gy (range 10 - 60 Gy); left optic nerve, 42.6 Gy (range 10 - 60 Gy); and optic chiasm, 48.2 Gy (range 10 - 65 Gy). Daily fractionation ranged from 1.5 to 1.8 Gy. Pattern VER testing distinguishes compressive or ischemic effects of tumor on the visual system from radiation retinopathy or optic neuropathy on the basis of the conduction amplitude and delay pattern. Prechiasm, chiasm, and postchiasm injuries are distinguishable by analyzing VER changes. Four evoked responses were obtained for each eye, each representing the average of 100 stimulus reversals. Results: VER was normal in 11 patients and abnormal in 13 patients. Only 2 patients (8%) had VER evidence of radiation injury to the visual system, one of whom had visual compromise. The other 11 abnormal patients had characteristic VER changes attributable to tumor or surgical damage. There was no significant difference in the radiation doses given to any subgroup. The one patient with radiation retinopathy had received 55-60 Gy to the posterior globe. Ten years

  4. Using Thermal Radiation in Detection of Negative Obstacles

    Science.gov (United States)

    Rankin, Arturo L.; Matthies, Larry H.

    2009-01-01

    A method of automated detection of negative obstacles (potholes, ditches, and the like) ahead of ground vehicles at night involves processing of imagery from thermal-infrared cameras aimed at the terrain ahead of the vehicles. The method is being developed as part of an overall obstacle-avoidance scheme for autonomous and semi-autonomous offroad robotic vehicles. The method could also be applied to help human drivers of cars and trucks avoid negative obstacles -- a development that may entail only modest additional cost inasmuch as some commercially available passenger cars are already equipped with infrared cameras as aids for nighttime operation.

  5. Test and further development of a silicon picsel detector for detecting ionising radiation

    International Nuclear Information System (INIS)

    Lechner, P.

    1990-12-01

    The concept of a silicon detector with a MOSFET as an integrating amplification element (DEP-MOSFET) is introduced. The method of functioning of different version and a picture cell (picsel) detector, which makes energy and location resolution possible, is discussed. Quantitative relationships which describe the operation of the component as a detector, and quantitative relationships for the energy resolution of a DEP-MOSFET are derived theoretically. Measurements provide the proof of the detection function of different versions and the confirmation of the results of the theoretical model. The excellent noise properties of DEP-MOSFET detectors with closed structure are pointed out. The further development of the explained detector concept by integration of a JFET as the amplifying element (here introduced in the form of a computer simulation and quantitative relationships which describe the behaviour as a detector) promises progress with regard to energy resolution and radiation resistance, and offers the possibility of producing a picsel detector made from closed structures with little technological effort. (orig.) [de

  6. EFFECT OF A RADIATION COOLING AND HEATING FUNCTION ON STANDING LONGITUDINAL OSCILLATIONS IN CORONAL LOOPS

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S.; Nakariakov, V. M.; Moon, Y.-J., E-mail: sanjaykumar@khu.ac.kr [School of Space Research, Kyung Hee University, Yongin, 446-701, Gyeonggi (Korea, Republic of)

    2016-06-10

    Standing long-period (with periods longer than several minutes) oscillations in large, hot (with a temperature higher than 3 MK) coronal loops have been observed as the quasi-periodic modulation of the EUV and microwave intensity emission and the Doppler shift of coronal emission lines, and they have been interpreted as standing slow magnetoacoustic (longitudinal) oscillations. Quasi-periodic pulsations of shorter periods, detected in thermal and non-thermal emissions in solar flares could be produced by a similar mechanism. We present theoretical modeling of the standing slow magnetoacoustic mode, showing that this mode of oscillation is highly sensitive to peculiarities of the radiative cooling and heating function. We generalized the theoretical model of standing slow magnetoacoustic oscillations in a hot plasma, including the effects of the radiative losses and accounting for plasma heating. The heating mechanism is not specified and taken empirically to compensate the cooling by radiation and thermal conduction. It is shown that the evolution of the oscillations is described by a generalized Burgers equation. The numerical solution of an initial value problem for the evolutionary equation demonstrates that different dependences of the radiative cooling and plasma heating on the temperature lead to different regimes of the oscillations, including growing, quasi-stationary, and rapidly decaying. Our findings provide a theoretical foundation for probing the coronal heating function and may explain the observations of decayless long-period, quasi-periodic pulsations in flares. The hydrodynamic approach employed in this study should be considered with caution in the modeling of non-thermal emission associated with flares, because it misses potentially important non-hydrodynamic effects.

  7. Detection limits by EPR spectroscopy of cumulated doses ionizing radiations in molluscs shells

    International Nuclear Information System (INIS)

    Ostrowski, K.; Burlinska, G.; Dziedzic-Goclawska, A.; Stachowicz, W.; Michalik, J.; Sadlo, J.

    1997-01-01

    The exposure of waters to ionizing radiation from radionuclides stored in concrete containers or freed in nuclear accidents or underwater eruption might be difficult to be proved, when currents, rains, exchange of water displace sand soils or rocks in the bottom. Ionizing radiation evokes stable paramagnetic centers in the crystalline lattice of mineral components in bones as well as in exoskeletons of most molluscs, which are detected by the EPR spectroscopy and could be used as an indicator of the exposure to the action of radiation during prolonged period of time. (authors)

  8. Power supply connection for ionizing radiation detection probes

    International Nuclear Information System (INIS)

    Zajic, J.

    1990-01-01

    One wire of the supply line is connected, through a diode in the forward direction, to the input terminal of the voltage stabilizer, and through the first resistor to the current limiter terminal of the voltage stabilizer, and also directly to the pulse separator terminal. The current limiter terminal of the voltage stabilizer is connected, through the second resistor, to the output terminal of the voltage stabilizer, and through the first capacitor to the voltage stabilizer earthing terminal, the earthing terminal of the pulse separator and through the other wire of the supply line to the earthing terminal of the detection probe. Furthermore, the input terminal of the voltage stabilizer is connected to a parallel combination of the third resistor with the second capacitor, whose other end is connected to the earthing terminal of the voltage stabilizer. The main asset of this connection consists in the high-frequency matching of the supply line being accomplished by a suitable choice of the resistor value without affecting the voltage for the detection probe. (M.D.)

  9. Detection of radiation-induced hydrocarbons in baked sponge cake prepared with irradiated liquid egg

    International Nuclear Information System (INIS)

    Schulzki, G.; Spiegelberg, A.; Boegl, K.W.; Schreiber, G.A.

    1995-01-01

    For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg. (Author)

  10. Detection of radiation-induced hydrocarbons in baked sponged cake prepared with irradiated liquid egg

    Science.gov (United States)

    Schulzki, G.; Spiegelberg, A.; Bögl, K. W.; Schreiber, G. A.

    1995-02-01

    For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg.

  11. Radiation detection with Nb/Al-AlOx/Al/Nb superconducting tunnel junctions

    International Nuclear Information System (INIS)

    Matsumura, Atsuki; Takahashi, Toru; Kurakado, Masahiko

    1992-01-01

    Superconductor radiation detectors have the possibility of 20-30 times better energy resolution than that of a high resolution Si detector. We fabricated Nb/Al-AlOx/Al/Nb superconducting tunnel junctions with low leakage current. X rays were detected with large area junctions of 178x178 μm 2 . High energy resolution of 160 eV for 5.9 keV was obtained. We also fabricated series connected junctions which covers a rather large area of 4x4 mm 2 . α particles injected into the rear substrate were detected using nonthermal phonons induced by the radiations in the substrate. (author)

  12. Detection capabilities and accuracy requirements of concentrations of radioactive material in air for radiation protection purposes

    International Nuclear Information System (INIS)

    Brodsky, A.

    1987-01-01

    Recent developments in the formulation of detection capability and accuracy criteria for bioassay measurements will be interpreted and adapted to provide similar criteria for the measurement of air concentrations of radioactive material for radiation protection purposes. Considerations of accuracy will be related to the known variability of measurement processes, as well as the uncertainties in the calculated limits of intake that serve as the basis of regulatory and voluntary standards of practice. Formulations and criteria will be presented for minimum detection amounts (MDA) and precision and bias of measurements for radiation protection purposes. 17 references

  13. Transient photoconductive gain in a-Si:H devices and its applications in radiation detection

    International Nuclear Information System (INIS)

    Lee, H.K.; Suh, T.S.; Choe, B.Y.; Shinn, K.S.; Perez-Mendez, V.

    1997-01-01

    Using the transient behavior of the photoconductive-gain mechanism, a signal gain in radiation detection with a-Si:H devices may be possible. The photoconductive gain mechanism in two types of hydrogenated amorphous silicon devices, p-i-n and n-i-n configurations, was investigated in connection with applications to radiation detection. Photoconductive gain was measured in two time scales: one for short pulses of visible light ( 2 . Various gain results are discussed in terms of the device structure, applied bias and dark-current density. (orig.)

  14. Detection matrix of an electromagnetic radiation and radiological image intensifier comprising such a matrix

    International Nuclear Information System (INIS)

    Fraleux, Jean.

    1982-01-01

    This invention concerns a detection matrix comprising, in an electrode lattice of lines and columns, addressing means constituted of thin film technology MOS transistors and photoconductances which enable the number of unit module crossings to be halved and to bring about an increase in the effective detection area. This detection matrix is employed in radiological image intensifiers where it ensures the conversion of incident X photons into reading electric signals or only the detection of a visible radiation in the case where the incident X photons are converted into lesser energy photons by a scintillator. The scintillator is then formed of a panel brought into contact with the detector mosaic [fr

  15. Functional status of liverin conditions of radiation and chemical exposure

    Directory of Open Access Journals (Sweden)

    O. V. Severynovs’ka

    2005-09-01

    Full Text Available Chronic influences of low-intensity X-rays in doses of 0.15 and 0.25 Gr and mix of heavy metals salts in a dose of 2 EPC (extreme permissible concentrations for each metal, as a single factor or as a combination of factors, on the state of pro-/antioxidative system in a rat liver have been studied. Analysis of the data concerning combined influences allows to conclude that effects under these doses have some differences: a splash of processes of lipid peroxidation are observed in both causes, but under the lower dose an additivity takes place, and under the dose of 0.25 Gr a synergism of the agent effects in relation to the development of peroxidative reactions is registered. The results testify that technogenic contamination of water with heavy metals worsens the action of radiation factor, specifically, eliminates a hormetic splash of antioxidative activity at 0.15 Gr. Biochemical indexes of the liver activity, as a central organ of a general metabolism, and a structure of morbidity have been studied in liquidators of the Chernobyl accident from industrial Prydnieprovie region. Disturbances of liver functions have been shown, especially in persons obtained the exposure dose about 0.25 Gr. A comparison of these results and data of tests with laboratory animals reveals their mutual accordance and supports a relevancy of extrapolation of data of model experiments on a person health state, which undergone a similar influence.

  16. Current state of commercial radiation detection equipment for homeland security applications

    International Nuclear Information System (INIS)

    Klann, R.T.; Shergur, J.; Mattesich, G.

    2009-01-01

    With the creation of the U.S. Department of Homeland Security (DHS) came the increased concern that terrorist groups would attempt to manufacture and use an improvised nuclear device or radiological dispersal device. As such, a primary mission of DHS is to protect the public against the use of these devices and to assist state and local responders in finding, locating, and identifying these types of devices and materials used to manufacture these devices. This assistance from DHS to state and local responders comes in the form of grant money to procure radiation detection equipment. In addition to this grant program, DHS has supported the development of American National Standards Institute standards for radiation detection equipment and has conducted testing of commercially available instruments. This paper identifies the types and kinds of commercially available equipment that can be used to detect and identify radiological material - for use in traditional search applications as well as primary and secondary screening of personnel, vehicles, and cargo containers. In doing so, key considerations for the conduct of operations are described as well as critical features of the instruments for specific applications. The current state of commercial instruments is described for different categories of detection equipment including personal radiation detectors, radioisotope identifiers, man-portable detection equipment, and radiation portal monitors. In addition, emerging technologies are also discussed, such as spectroscopic detectors and advanced spectroscopic portal monitors

  17. Apparatus and method for the simultaneous detection of neutrons and ionizing electromagnetic radiation

    Science.gov (United States)

    Bell, Zane W.

    2000-01-01

    A sensor for simultaneously detecting neutrons and ionizing electromagnetic radiation comprising: a sensor for the detection of gamma radiation, the sensor defining a sensing head; the sensor further defining an output end in communication with the sensing head; and an exterior neutron-sensitive material configured to form around the sensing head; wherein the neutron-sensitive material, subsequent to the capture of the neutron, fissions into an alpha-particle and a .sup.7 Li ion that is in a first excited state in a majority of the fissions, the first excited state decaying via the emission of a single gamma ray at 478 keV which can in turn be detected by the sensing head; and wherein the sensing head can also detect the ionizing electromagnetic radiation from an incident radiation field without significant interference from the neutron-sensitive material. A method for simultaneously detecting neutrons and ionizing electromagnetic radiation comprising the steps of: providing a gamma ray sensitive detector comprising a sensing head and an output end; conforming an exterior neutron-sensitive material configured to form around the sensing head of the detector; capturing neutrons by the sensing head causing the neutron-sensitive material to fission into an alpha-particle and a .sup.7 Li ion that is in a first excited state in a majority of the fissions, the state decaying via the emission of a single gamma ray at 478 keV; sensing gamma rays entering the detector through the neutron-sensitive material; and producing an output through a readout device coupled to the output end; wherein the detector provides an output which is proportional to the energy of the absorbed ionizing electromagnetic radiation.

  18. Radiation Detection and Classification of Heavy Oxide Inorganic Scintillator Crystals for Detection of Fast Neutrons

    Science.gov (United States)

    2016-06-01

    response, diffuse source, collimated source 15. NUMBER OF PAGES 101 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified 18...protecting the homeland, building security globally, and projecting power and winning decisively [1]. Nuclear material detection is embedded in two...detection. According to Glasstone and Dolan [4] as well as numerous other experts, there are fundamentally three isotopes that could practically be used

  19. Echo detected EPR as a tool for detecting radiation-induced defect signals in pottery

    International Nuclear Information System (INIS)

    Zoleo, Alfonso; Bortolussi, Claudia; Brustolon, Marina

    2011-01-01

    Archaeological fragments of pottery have been investigated by using CW-EPR and Echo Detected EPR (EDEPR). EDEPR allows to remove the CW-EPR dominant Fe(III) background spectrum, hiding much weaker signals potentially useful for dating purpose. EDEPR spectra attributed to a methyl radical and to feldspar defects have been recorded at room and low temperature for an Iron Age cooking ware (700 B.C.). A study on the dependence of EDEPR intensity over absorbed dose on a series of γ-irradiated brick samples (estimated age of 562 ± 140 B.C.) has confirmed the potential efficacy of the proposed method for spotting defect signals out of the strong iron background. - Highlights: → Fe(III) CW-EPR signals cover CW-EPR-detectable defects in ceramics. → Echo detected EPR gets rid of Fe(III) signals, disclosing defect signals. → Echo detected EPR detects defect signals even at relatively low doses.

  20. Solving Inverse Detection Problems Using Passive Radiation Signatures

    International Nuclear Information System (INIS)

    Favorite, Jeffrey A.; Armstrong, Jerawan C.; Vaquer, Pablo A.

    2012-01-01

    The ability to reconstruct an unknown radioactive object based on its passive gamma-ray and neutron signatures is very important in homeland security applications. Often in the analysis of unknown radioactive objects, for simplicity or speed or because there is no other information, they are modeled as spherically symmetric regardless of their actual geometry. In these presentation we discuss the accuracy and implications of this approximation for decay gamma rays and for neutron-induced gamma rays. We discuss an extension of spherical raytracing (for uncollided fluxes) that allows it to be used when the exterior shielding is flat or cylindrical. We revisit some early results in boundary perturbation theory, showing that the Roussopolos estimate is the correct one to use when the quantity of interest is the flux or leakage on the boundary. We apply boundary perturbation theory to problems in which spherically symmetric systems are perturbed in asymmetric nonspherical ways. We apply mesh adaptive direct search (MADS) algorithms to object reconstructions. We present a benchmark test set that may be used to quantitatively evaluate inverse detection methods.

  1. Detection of a stochastic background of gravitational radiation by the Doppler tracking of spacecraft

    International Nuclear Information System (INIS)

    Mashhoon, B.; Grishchuk, L.P.

    1980-01-01

    The possibility of detection of an isotropic background gravitational radiation of a stochastic nature by the method of Doppler tracking of spacecraft is considered. In the geometrical optics limit, the general formula for the frequency shift of an electromagnetic signal in the gravitational radiation field is discussed, and it is shown to be gauge (or rather Lie) independent. A detailed examination of the propagation of a free electromagnetic wave in a gravitational radiation field shows that no resonance phenomena can be expected. Thus, the results valid in the geometrical optics limit are also approximately valid for any gravitational radiation spectrum dominated by wavelengths large compared to that of the electromagnetic signal. The ''Doppler noise'' due to a stochastic background is evaluated, and it is shown to depend on the total energy density of the background and a parameter that is a characteristic of the aradiation spectrum and the detection system used. A background gravitational radiation with an energy density comparable to the electromagnetic (approx.3 K) background and a spectrum dominated by wavelengths > or approx. =1 AU may be detectable in the near future by the Doppler tracking of interplanetary spacecraft

  2. Nitrogen deficiency detection using reflected shortwave radiation from irrigated corn canopies

    International Nuclear Information System (INIS)

    Blackmer, T.M.; Schepers, J.S.; Varvel, G.E.; Walter-Shea, E.A.

    1996-01-01

    Techniques that measure the N status of corn (Zea mays L.) can aid in management decisions that have economic and environmental implications. This study was conducted to identify reflected electromagnetic wavelengths most sensitive to detecting N deficiencies in a corn canopy with the possibility for use as a management tool. Reflected shortwave radiation was measured from an irrigated corn N response trial with four hybrids and five N rates at 0, 40, 80, 120, and 160 kg N ha -1 in 1992 and 0, 50, 100, 150, and 200 kg N ha -1 in 1993. A portable spectroradiometer was used to measure reflected radiation (400-1100 nm in 1992, 350-1050 nm in 1993) from corn canopies at approximately the R5 growth stage. Regression analyses revealed that reflected radiation near 550 and 710 nm was superior to reflected radiation near 450 or 650 nm for detecting N deficiencies. The ratio of light reflectance between 550 and 600 nm to light reflectance between 800 and 900 nm also provided sensitive detection of N stress. In 1993, an inexpensive photometric cell, which has peak sensitivity to light centered at 550 nm, was also used to measure reflected radiation from a corn canopy. Photometric cell readings correlated with relative grain yield (P < 0.001, r 2 = 0.74), but more research will be required to develop procedures to account for varying daylight conditions. These results provide information needed for the development of variable-rate fertilizer N application technology. (author)

  3. Sensitive Detection: Photoacoustics, Thermography, and Optical Radiation Pressure

    Energy Technology Data Exchange (ETDEWEB)

    Diebold, Gerald J. [Brown Univ., Providence, RI (United States)

    2017-04-21

    Research during the granting period has been carried out in several areas concerned with sensitive detection. An infrared pyrometer based on the photoacoustic effect has been developed. The sensitivity of this instrument to temperature differentials has been shown to be 50 mK. An investigation of transients that accompany photoacoustic waves generated by pulsed lasers has been carried out. Experiments have shown the existence of the transients, and a theory based on rapid heat diffusion has been developed. The photoacoustic effect in one dimension is known to increase without bound (in the linear acoustics regime) when an optical beam moves in a fluid at the sound speed. A solution to the wave equation for pressure has been found that describes the photoacoustic effect in a cell where an infrared optical grating moves at the sound speed. It was shown that the amplification effect exists along with a cavity resonance that can be used to great advantage in trace gas detection. The theory of the photoacoustic effect in a structure where the acoustic properties periodically vary in a one-dimensional based has been formulated based on solutions to a Mathieu equation. It was found that it is possible to excite photoacoustic waves within the band gaps to produce large amplitude acoustic waves. The idea of self-oscillation in a photoacoustic cell using a continuous laser has been investigated. A theory has been completed showing that in a compressive wave, the absorption increases as a result of the density increase leading to further absorption and hence an increased amplitude photoacoustic effect with the result that in a resonator, self-oscillation can place. Experiments have been carried out where irradiation of a suspension of absorbing carbon particles with a high power laser has been shown to result in cavitation luminescence. That is, following generation of CO and H2 from the carbon particles through the carbon-steam reaction, an expanding gas bubble is

  4. Synthesis and characterization of lanthanide based nanomaterials for radiation detection and biomedical applications

    Science.gov (United States)

    Yao, Mingzhen

    2011-12-01

    Lanthanide based nanomaterials have shown a great potential in various areas such as luminescence imaging, luminescent labels, and detection of cellular functions. Due to the f-f transitions of the metal ion, luminescence of lanthanide ions is characterized by sharp and narrow emissions. In this dissertation lanthanide based nanoparticles such as Ce3+, Eu3+ and other lanthanide ions doped LaF3 were synthesized, their characterization, encapsulation and embedding into hybrid matrix were investigated and some of their biomedical and radiological applications were studied. DMSO is a common solvent which has been used widely for biological applications. LaF3:Ce nanoparticles were synthesized in DMSO and it was found that their fluorescent emission originates from the metal-to-ligand charge-transfer excited states. After conjugation with PpIX and then encapsulation within PLGA, the particles show efficient uptake by cancer cells and great cytotoxicity, which is promising for applications in cancer treatments. However, the emission of Eu3+ in DMSO is totally different from LaF3:Ce, very strong characteristic luminescence is observed but no emissions from metal-to-ligand charge-transfer excited states as observed in LaF3:Ce in DMSO. Besides, it is very interesting to see that the coupling of Eu 3+ with O-H oscillations after water was introduced has an opposite effect on emission peaks at 617 nm and its shoulder peak at 613 nm. As a result, the intensity ratio of these two emissions has a nearly perfect linear dependence on increasing water concentration in Eu-DMSO, which provides a very convenient and valuable method for water determination in DMSO. Ce3+ has been well known as an emitter for radiation detection due to its very short decay lifetime. However, its emission range limited the environment in which the detection system works. Whereas, Quantum dots have high luminescence quantum efficiency but their low stopping power results in very weak scintillation

  5. Stimulatory effect of low dose radiation on the immune function in tumor-bearing mice

    International Nuclear Information System (INIS)

    Zhang Ying; Li Xiujuan; Li Xiuyi; Liu Shuzheng

    1999-01-01

    Objective: The author aims at investigating the effect of whole body irradiation (WBI) with low dose radiation on immune function in tumor-bearing mice. Methods: C57BL/6J mine implanted with Lewis lung carcinoma cells in the right thighs were used as an experimental animal model. WBI with 75 mGy X-rays was given at the 10 th day after implantation and immunological parameters were detected 18 hours after irradiation. The immunological parameters included the spontaneous incorporation of 3 H-TdR into thymocytes, the number of splenocytes, the reaction of splenocytes to ConA and LPS, the splenic production of IL-2, the cytotoxic activities of natural killer (NK) and lymphokine activated killer cells (LAK) as well as specific cytotoxic T lymphocytes (CTL). Results: The immunological parameters of irradiated tumor-bearing mice were significantly increased compared with those of sham-irradiated tumor-bearing mice (P<0.05∼0.01). Conclusion: Low dose radiation could significantly increase the immune function of tumor-bearing mice, and this stimulatory effect may be of some potential significance in tumor therapy

  6. Signal development in silicon sensors used for radiation detection

    International Nuclear Information System (INIS)

    Becker, Julian

    2010-08-01

    This work investigates the charge collection properties in silicon sensors. In order to perform the investigations a setup for measurements utilizing the Transient Current Technique (TCT) has been designed and built. Optical lasers with different wavelengths and short pulses (FWHM<100 ps) have been used to create charge carriers in the sensor volume. A new parameterization of charge carrier mobilities in bulk silicon as function of electric field and temperature was derived for two different crystal orientations from investigations on pad sensors with low charge carrier densities. In the course of these investigations a simulation program for current pulses was developed. The program simulates current pulses, which are induced by drift and diffusion of charge carriers for pad sensors, and approximately for strip and pixel sensors. The simulation program could be used to describe the current pulses of irradiated sensors. Additionally, using the simulation program, it was shown that impact ionization is a possible reason for the recently reported charge multiplication effects in highly irradiated sensors. The central topic of this work is the investigation of effects of high charge carrier densities, so called plasma effects. In this work plasma effects were created by focusing the lasers. The measurements of the plasma efffects on pad sensors were used as reference measurements for simulations performed by WIAS in Berlin. It was shown that using charge transport models accepted in literature, the observed plasma effects cannot be described. Measurements on strip sensors were performed with regards to the detector development for the European XFEL. Measurements of peak currents and charge collection times as function of photon intensity and applied bias voltage allowed the determination of optimum operation parameters of the Adaptive Gain Integration Pixel Detector (AGIPD), which will be used at the European XFEL. Utilizing position sensitive measurements on strip

  7. Signal development in silicon sensors used for radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Julian

    2010-08-15

    This work investigates the charge collection properties in silicon sensors. In order to perform the investigations a setup for measurements utilizing the Transient Current Technique (TCT) has been designed and built. Optical lasers with different wavelengths and short pulses (FWHM<100 ps) have been used to create charge carriers in the sensor volume. A new parameterization of charge carrier mobilities in bulk silicon as function of electric field and temperature was derived for two different crystal orientations from investigations on pad sensors with low charge carrier densities. In the course of these investigations a simulation program for current pulses was developed. The program simulates current pulses, which are induced by drift and diffusion of charge carriers for pad sensors, and approximately for strip and pixel sensors. The simulation program could be used to describe the current pulses of irradiated sensors. Additionally, using the simulation program, it was shown that impact ionization is a possible reason for the recently reported charge multiplication effects in highly irradiated sensors. The central topic of this work is the investigation of effects of high charge carrier densities, so called plasma effects. In this work plasma effects were created by focusing the lasers. The measurements of the plasma efffects on pad sensors were used as reference measurements for simulations performed by WIAS in Berlin. It was shown that using charge transport models accepted in literature, the observed plasma effects cannot be described. Measurements on strip sensors were performed with regards to the detector development for the European XFEL. Measurements of peak currents and charge collection times as function of photon intensity and applied bias voltage allowed the determination of optimum operation parameters of the Adaptive Gain Integration Pixel Detector (AGIPD), which will be used at the European XFEL. Utilizing position sensitive measurements on strip

  8. Step-by-Step Simulation of Radiation of Radiation Chemistry Using Green Functions for Diffusion-Influenced Reactions

    Science.gov (United States)

    Plante, Ianik; Cucinotta, Francis A.

    2011-01-01

    The irradiation of biological systems leads to the formation of radiolytic species such as H(raised dot), (raised dot)OH, H2, H2O2, e(sup -)(sub aq), etc.[1]. These species react with neighboring molecules, which result in damage in biological molecules such as DNA. Radiation chemistry is there for every important to understand the radiobiological consequences of radiation[2]. In this work, we discuss an approach based on the exact Green Functions for diffusion-influenced reactions which may be used to simulate radiation chemistry and eventually extended to study more complex systems, including DNA.

  9. Radiation cross-linking of ethylene vinyl alcohol copolymer functionalized with m-isopropenyl-α,α-dimethyl benzyl isocyanate

    International Nuclear Information System (INIS)

    Ekman, K.B.; Naesman, J.H.

    1993-01-01

    An ethylene vinyl alcohol copolymer was functionalized with m-isopropenyl-α,α-dimethyl benzyl isocyanate using reactive processing in a mixer. The functionalization introduces pendant unsaturation to the polymer, which allows radiation cross-linked to gel contents >70% at radiation doses below 100 kGy. Unfunctionalized ethylene vinyl alcohol copolymer, on the other hand, forms no gel upon irradiation. The functionalization was completed within a few minutes of reactive mixing, which was confirmed with both FTIR and 13 C-NMR measurements. The oxygen permeability of ethylene vinyl alcohol copolymer increased with increasing degree of functionalization, and irradiation of the samples formed trapped radicals, which act as oxygen scavengers. Consequently no oxygen permeability was detected. However, radical activity was inhibited by annealing the samples at 110 C resulting in a 24% higher oxygen permeability value for the irradiated unfunctionalized copolymer. The oxygen permeability values of the irradiated functionalized samples were approximately 13% lower. Laminates of m-isopropenyl-α,α-dimethyl benzyl isocyanate functionalized ethylene vinyl alcohol copolymer and m-isopropenyl-α,α-dimethyl benzyl isocyanate functionalized ethylene hydroxyethyl methacrylate copolymer acquired improved adhesive strength both at dry and wet conditions as well as at elevated temperature upon exposure to radiation

  10. Tansig activation function (of MLP network) for cardiac abnormality detection

    Science.gov (United States)

    Adnan, Ja'afar; Daud, Nik Ghazali Nik; Ishak, Mohd Taufiq; Rizman, Zairi Ismael; Rahman, Muhammad Izzuddin Abd

    2018-02-01

    Heart abnormality often occurs regardless of gender, age and races. This problem sometimes does not show any symptoms and it can cause a sudden death to the patient. In general, heart abnormality is the irregular electrical activity of the heart. This paper attempts to develop a program that can detect heart abnormality activity through implementation of Multilayer Perceptron (MLP) network. A certain amount of data of the heartbeat signals from the electrocardiogram (ECG) will be used in this project to train the MLP network by using several training algorithms with Tansig activation function.

  11. Process and devices of detection of hard electromagnetic or particle radiations using a superconducting element

    International Nuclear Information System (INIS)

    Drukier, A.K.; Valette, Claude; Waysand, Georges.

    1975-01-01

    The invention relates to processes and systems for the detection of hard electromagnetic or particle radiations and the sensors fitted to these systems. 'Hard radiations' means those whose energy is greater than a variable threshold, depending on the applications, but always more than 5 keV. The use of these sensors and the associated systems can therefore be envisaged in radiography and also in emission gammagraphy in the biological, anatomic and medical fields. In these processes, in order to detect a photon or a radiation particle, use is made of the transition phenomenon of a homogeneous grain of superconducting material of the first kind, from the metastable superconducting state to the normal state, under the effect of a photoelectron ejected by the impact of the photon or of the particle on the grain of superconducting material [fr

  12. Performance Analysis of Si-Based Ultra-Shallow Junction Photodiodes for UV Radiation Detection

    NARCIS (Netherlands)

    Shi, L.

    2013-01-01

    This thesis presents a performance investigation of newly-developed ultra-shallow junction photodiodes (PureB-diodes) for ultraviolet (UV) radiation detection. The photodiodes are fabricated by pure boron chemical vapor deposition (PureB CVD) technology, which can provide nanometer-thin boron

  13. Detecting part of the transition radiation detector for the GINES installation at UNK

    International Nuclear Information System (INIS)

    Shikhliarov, K.K.; Gavalian, V.G.; Aginian, M.A.

    1995-01-01

    The detecting part of an X-ray transition radiation detector based on thin-walled mylar straws is considered in this paper. The performance of xenon-filled straws in the self-quenching mode is studied in detail. The measurements have been carried out both with radioactive sources and under the electron beam of the Yerevan synchrotron. (orig.)

  14. Development of front-end ASIC for radiation detection and measurement

    International Nuclear Information System (INIS)

    Shimazoe, K.

    2014-01-01

    For realizing the multichannel spectroscopy of gamma rays, the technology of integrated circuits is necessary. Multi-channel gamma ray spectroscopy is very important for many applications including the medical imaging and the environmental monitoring. The current progress in the development of application specific integrated circuit (ASIC) for multi-channel radiation detection is introduced and reviewed. (author)

  15. Operating a Microwave Radiation Detection Monitor. Module 10. Vocational Education Training in Environmental Health Sciences.

    Science.gov (United States)

    Consumer Dynamics Inc., Rockville, MD.

    This module, one of 25 on vocational education training for careers in environmental health occupations, contains self-instructional materials on operating a microwave radiation detection monitor. Following guidelines for students and instructors and an introduction that explains what the student will learn are three lessons: (1) testing the…

  16. Design and construction of tank robot for detection and searching of radiation sources

    International Nuclear Information System (INIS)

    Rio Isman; Djiwo Harsono; Adi Abimanyu

    2016-01-01

    Developments of robotics technology can be implemented for searching the lost radiation source. Radiation source lost case allows the radiation dose exceeding NBD received by radiation worker when security precautions are taken. This research propose a robot tank that can help in detection and searching radiation sources. The robot consists of a micro controller board Arduino Mega 2560, XBee Pro S radio frequency modules, Gaps receiver U-B lox Neo-Mn-0-01, a servo motor and two DC motors. In this research, the amount of radiation is calculated in 0-5 volt analog voltage that is simulated using a potentiometer and then converted to a digital voltage value (0-1023) using ADC 10 bit Arduino Mega 2560. Results of the research show that the robot has a size of 28.7 cm x 24.8 cm x 11 cm, able to move forward with a speed of 0.477 m/s and are capable to rotate in 24 angles. Data transmission can be performed wireless up to 113 m in an open area without any changes of format and length of the data. Robot capable to rotate and move towards the angle which has the largest voltage readings so can predict the location of the radiation source. (author)

  17. MRI-alone radiation therapy planning for prostate cancer: Automatic fiducial marker detection

    International Nuclear Information System (INIS)

    Ghose, Soumya; Mitra, Jhimli; Rivest-Hénault, David; Fazlollahi, Amir; Fripp, Jurgen; Dowling, Jason A.; Stanwell, Peter; Pichler, Peter; Sun, Jidi; Greer, Peter B.

    2016-01-01

    Purpose: The feasibility of radiation therapy treatment planning using substitute computed tomography (sCT) generated from magnetic resonance images (MRIs) has been demonstrated by a number of research groups. One challenge with an MRI-alone workflow is the accurate identification of intraprostatic gold fiducial markers, which are frequently used for prostate localization prior to each dose delivery fraction. This paper investigates a template-matching approach for the detection of these seeds in MRI. Methods: Two different gradient echo T1 and T2* weighted MRI sequences were acquired from fifteen prostate cancer patients and evaluated for seed detection. For training, seed templates from manual contours were selected in a spectral clustering manifold learning framework. This aids in clustering “similar” gold fiducial markers together. The marker with the minimum distance to a cluster centroid was selected as the representative template of that cluster during training. During testing, Gaussian mixture modeling followed by a Markovian model was used in automatic detection of the probable candidates. The probable candidates were rigidly registered to the templates identified from spectral clustering, and a similarity metric is computed for ranking and detection. Results: A fiducial detection accuracy of 95% was obtained compared to manual observations. Expert radiation therapist observers were able to correctly identify all three implanted seeds on 11 of the 15 scans (the proposed method correctly identified all seeds on 10 of the 15). Conclusions: An novel automatic framework for gold fiducial marker detection in MRI is proposed and evaluated with detection accuracies comparable to manual detection. When radiation therapists are unable to determine the seed location in MRI, they refer back to the planning CT (only available in the existing clinical framework); similarly, an automatic quality control is built into the automatic software to ensure that all gold

  18. MRI-alone radiation therapy planning for prostate cancer: Automatic fiducial marker detection

    Energy Technology Data Exchange (ETDEWEB)

    Ghose, Soumya, E-mail: soumya.ghose@case.edu; Mitra, Jhimli [Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106 and CSIRO Health and Biosecurity, The Australian e-Health & Research Centre, Herston, QLD 4029 (Australia); Rivest-Hénault, David; Fazlollahi, Amir; Fripp, Jurgen; Dowling, Jason A. [CSIRO Health and Biosecurity, The Australian e-Health & Research Centre, Herston, QLD 4029 (Australia); Stanwell, Peter [School of health sciences, The University of Newcastle, Newcastle, NSW 2308 (Australia); Pichler, Peter [Department of Radiation Oncology, Cavalry Mater Newcastle Hospital, Newcastle, NSW 2298 (Australia); Sun, Jidi; Greer, Peter B. [School of Mathematical and Physical Sciences, The University of Newcastle, Newcastle, NSW 2308, Australia and Department of Radiation Oncology, Cavalry Mater Newcastle Hospital, Newcastle, NSW 2298 (Australia)

    2016-05-15

    Purpose: The feasibility of radiation therapy treatment planning using substitute computed tomography (sCT) generated from magnetic resonance images (MRIs) has been demonstrated by a number of research groups. One challenge with an MRI-alone workflow is the accurate identification of intraprostatic gold fiducial markers, which are frequently used for prostate localization prior to each dose delivery fraction. This paper investigates a template-matching approach for the detection of these seeds in MRI. Methods: Two different gradient echo T1 and T2* weighted MRI sequences were acquired from fifteen prostate cancer patients and evaluated for seed detection. For training, seed templates from manual contours were selected in a spectral clustering manifold learning framework. This aids in clustering “similar” gold fiducial markers together. The marker with the minimum distance to a cluster centroid was selected as the representative template of that cluster during training. During testing, Gaussian mixture modeling followed by a Markovian model was used in automatic detection of the probable candidates. The probable candidates were rigidly registered to the templates identified from spectral clustering, and a similarity metric is computed for ranking and detection. Results: A fiducial detection accuracy of 95% was obtained compared to manual observations. Expert radiation therapist observers were able to correctly identify all three implanted seeds on 11 of the 15 scans (the proposed method correctly identified all seeds on 10 of the 15). Conclusions: An novel automatic framework for gold fiducial marker detection in MRI is proposed and evaluated with detection accuracies comparable to manual detection. When radiation therapists are unable to determine the seed location in MRI, they refer back to the planning CT (only available in the existing clinical framework); similarly, an automatic quality control is built into the automatic software to ensure that all gold

  19. Graphene Field Effect Transistor-Based Detectors for Detection of Ionizing Radiation

    International Nuclear Information System (INIS)

    Jovanovic, Igor; Cazalas, Edward; Childres, I.; Patil, A.; Koybasi, O.; Chen, Y-P.

    2013-06-01

    We present the results of our recent efforts to develop novel ionizing radiation sensors based on the nano-material graphene. Graphene used in the field effect transistor architecture could be employed to detect the radiation-induced charge carriers produced in undoped semiconductor absorber substrates, even without the need for charge collection. The detection principle is based on the high sensitivity of graphene to ionization-induced local electric field perturbations in the electrically biased substrate. We experimentally demonstrated promising performance of graphene field effect transistors for detection of visible light, X-rays, gamma-rays, and alpha particles. We propose improved detector architectures which could result in a significant improvement of speed necessary for pulsed mode operation. (authors)

  20. A method to detect ultra high energy electrons using earth's magnetic field as a radiator

    Science.gov (United States)

    Stephens, S. A.; Balasubrahmanyan, V. K.

    1983-01-01

    It is pointed out that the detection of electrons with energies exceeding a few TeV, which lose energy rapidly through synchrotron and inverse Compton processes, would provide valuable information on the distribution of sources and on the propagation of cosmic rays in the solar neighborhood. However, it would not be possible to measure the energy spectrum beyond a few TeV with any of the existing experimental techniques. The present investigation is, therefore concerned with the possibility of detecting electrons with energies exceeding a few TeV on the basis of the photons emitted through synchrotron radiation in the earth's magnetic field. Attention is given to the synchrotron radiation of electrons in the earth's magnetic field, detector response and energy estimation, and the characteristics of an ideal detector, capable of detecting photons with energies equal to or greater than 20 keV.

  1. Hypothyroidism in a dog after surgery and radiation therapy for a functional thyroid adenocarcinoma

    International Nuclear Information System (INIS)

    Kramer, R.W.; Price, G.S.; Spodnick, G.J.

    1994-01-01

    Hypothyroidism was diagnosed in a dog which had undergone unilateral thyroid lobectomy and external beam irradiation (48 Gy in 3 Gy fractions) for a functional cystic thyroid adenocarcinoma. Hypothyroidism became biochemically apparent within 4 months of completion of radiation therapy, and clinically apparent within 7 months. Clinical signs resolved after thyroid hormone supplementation. The potential for alterations in thyroid function should be considered in any animal undergoing radiation therapy in which the thyroid gland is included in the radiation field. This potential may be greater if surgery and radiation are combined

  2. Design of a spreader bar crane-mounted gamma-ray radiation detection system

    Energy Technology Data Exchange (ETDEWEB)

    Grypp, Matthew D., E-mail: iglowgreen@neo.tamu.edu; Marianno, Craig M., E-mail: marianno@tamu.edu; Poston, John W., E-mail: j-poston@tamu.edu; Hearn, Gentry C., E-mail: ghearn@riacc.com

    2014-04-11

    Over 95% of imports entering the United States from outside North America arrive by sea at 329 ports of entry. These imports are packaged in more than 11 million cargo containers. Radiation portals monitors routinely scan cargo containers leaving port on specially-designed trucks. To accelerate the process, some commercial entities have placed detection systems on the spreader-bar cranes (SBCs) used to offload. Little is known about the radiation background profiles of systems operating on these cranes. To better understand the operational characteristics of these radiation detection systems; a research team from Texas A and M University (TAMU) mounted three thallium-doped sodium iodide [NaI(Tl)] detectors on an SBC at the Domestic Nuclear Detection Office's (DNDO) test track facility at the Port of Tacoma (PoT). These detectors were used to monitor background radiation levels and continuously recorded data during crane operations using a custom-built software package. Count rates and spectral data were recorded for various crane heights over both land and water. The results of this research created a background profile in which count rate was heavily dependent on position demonstrating how detector readings changed in the operational environment.

  3. Destruction of Raman biosignatures by ionising radiation and the implications for life detection on Mars.

    Science.gov (United States)

    Dartnell, Lewis R; Page, Kristian; Jorge-Villar, Susana E; Wright, Gary; Munshi, Tasnim; Scowen, Ian J; Ward, John M; Edwards, Howell G M

    2012-04-01

    Raman spectroscopy has proven to be a very effective approach for the detection of microorganisms colonising hostile environments on Earth. The ExoMars rover, due for launch in 2018, will carry a Raman laser spectrometer to analyse samples of the martian subsurface collected by the probe's 2-m drill in a search for similar biosignatures. The martian surface is unprotected from the flux of cosmic rays, an ionising radiation field that will degrade organic molecules and so diminish and distort the detectable Raman signature of potential martian microbial life. This study employs Raman spectroscopy to analyse samples of two model organisms, the cyanobacterium Synechocystis sp. PCC 6803 and the extremely radiation resistant polyextremophile Deinococcus radiodurans, that have been exposed to increasing doses of ionising radiation. The three most prominent peaks in the Raman spectra are from cellular carotenoids: deinoxanthin in D. radiodurans and β-carotene in Synechocystis. The degradative effect of ionising radiation is clearly seen, with significant diminishment of carotenoid spectral peak heights after 15 kGy and complete erasure of Raman biosignatures by 150 kGy of ionising radiation. The Raman signal of carotenoid in D. radiodurans diminishes more rapidly than that of Synechocystis, believed to be due to deinoxanthin acting as a superior scavenger of radiolytically produced reactive oxygen species, and so being destroyed more quickly than the less efficient antioxidant β-carotene. This study highlights the necessity for further experimental work on the manner and rate of degradation of Raman biosignatures by ionising radiation, as this is of prime importance for the successful detection of microbial life in the martian near subsurface.

  4. Radiation crosslinking of polymer materials and its functional properties

    International Nuclear Information System (INIS)

    Yoshii, Fumio

    2006-01-01

    It was found out that radiation crosslinking of biodegradable polymer such as poly (butylene succinate, PBS) and poly(ε-caprolactone, PCL) could be achieved by radiation in the presence of small amount of trimethallyl isocyanurate (TMAIC) or 1% triallyl isocyanurate (TAIC). Such modification is very effective to improve heat resistance for PBS and PCL. Poly (lactic acid, PLA) undergoes crosslinking effectively with 3% TAIC by radiation. Outstanding feature of these polymers is their biodegradability even after crosslinking. Radiation crosslinking of polysaccharide derivatives such as carboxymethyl-cellulose (CMC) is also achieved in aqueous solution at high concentration (paste-like state). The crosslinking behavior was largely affected by the degree of substitution (DS) and polymer concentration. After removal of water the dry CMC gel is used as water absorbent material. This dry gel is the most effective for removal of large amounts of water from organic wastes, resulting in the acceleration of their fermentation. Measurement of swelling ratio of the dry CMC gel in 0.9% NaCl aqueous solution was carried out to expand application fields for this material. Radiation crosslinked poly (vinyl alcohol) hydrogel was successfully commercialized from July 2004 as wound dressing for accelerated healing. Furthermore, this material was also used as gel protector to prevent shore sore and was further commercialized. (author)

  5. Instrumentation measurement and testing complex for detection and identification of radioactive materials using the emitted radiation

    International Nuclear Information System (INIS)

    Samossadny, V.T.; Dmitrenko, V.V.; Kadlin, V.V.; Kolesnikov, S.V.; Ulin, S.E.; Grachev, V.M.; Vlasik, K.F.; Dedenko, G.L.; Novikov, D.V.; Uteshev, Z.M.

    2006-01-01

    Simultaneous measurement of neutron and gamma radiation is a very usefull method for effective nuclear materials identification and control. The gamma-ray-neutron complex described in the paper is based on two multi-layer 3 He neutrons detectors and two High Pressure Xenon gamma-ray spectrometers assembled in one unit. All these detectors were callibrated on neutron and gamma-ray sources. The main characteristics of the instrumentation , its testing results and gamma-ray and neutron radiation parameters, which have been measured are represented in the paper. The gamma-neutron sources and fissile materials reliable detection and identification capability was demonstrated

  6. Accuracy and detection limits for bioassay measurements in radiation protection. Statistical considerations

    International Nuclear Information System (INIS)

    Brodsky, A.

    1986-04-01

    This report provides statistical concepts and formulas for defining minimum detectable amount (MDA), bias and precision of sample analytical measurements of radioactivity for radiobioassay purposes. The defined statistical quantities and accuracy criteria were developed for use in standard performance criteria for radiobioassay, but are also useful in intralaboratory quality assurance programs. This report also includes a literature review and analysis of accuracy needs and accuracy recommendations of national and international scientific organizations for radiation or radioactivity measurements used for radiation protection purposes. Computer programs are also included for calculating the probabilities of passing or failing multiple analytical tests for different acceptable ranges of bias and precision

  7. Detection of microwave radiation of cytochrome CYP102 A1 solution during the enzyme reaction

    Directory of Open Access Journals (Sweden)

    Yu.D. Ivanov

    2016-03-01

    Full Text Available Microwave radiation at 3.4–4.2 GHz frequency of the cytochrome P450 CYP102 A1 (BM3 solution was registered during the lauric acid hydroxylation reaction. The microwave radiation generation was shown to occur following the addition of electron donor NADPH to a system containing an enzyme and a substrate. The radiation occurs for the enzyme solutions with enzyme concentrations of 10−8 and 10−9 М. The microwave radiation effect elicited by the aqueous enzyme solution was observed for the first time. The results obtained can be used to elaborate a new approach to enzyme systems research, including studying of the mechanism of interaction of a functioning enzyme system with microenvironment.

  8. Detecting ship targets in spaceborne infrared image based on modeling radiation anomalies

    Science.gov (United States)

    Wang, Haibo; Zou, Zhengxia; Shi, Zhenwei; Li, Bo

    2017-09-01

    Using infrared imaging sensors to detect ship target in the ocean environment has many advantages compared to other sensor modalities, such as better thermal sensitivity and all-weather detection capability. We propose a new ship detection method by modeling radiation anomalies for spaceborne infrared image. The proposed method can be decomposed into two stages, where in the first stage, a test infrared image is densely divided into a set of image patches and the radiation anomaly of each patch is estimated by a Gaussian Mixture Model (GMM), and thereby target candidates are obtained from anomaly image patches. In the second stage, target candidates are further checked by a more discriminative criterion to obtain the final detection result. The main innovation of the proposed method is inspired by the biological mechanism that human eyes are sensitive to the unusual and anomalous patches among complex background. The experimental result on short wavelength infrared band (1.560 - 2.300 μm) and long wavelength infrared band (10.30 - 12.50 μm) of Landsat-8 satellite shows the proposed method achieves a desired ship detection accuracy with higher recall than other classical ship detection methods.

  9. Level Densities and Radiative Strength Functions in 170,171Yb

    International Nuclear Information System (INIS)

    Agvaanluvsan, U.; Schiller, A.; Becker, J.A.; Berstein, L.A.; Guttormsen, M.; Mitchell, G.E.; Rekstad, J.; Siem, S.; Voinov, A.

    2003-01-01

    Level densities and radiative strength functions in 171 Yb and 170 Yb nuclei have been measured with the 171 Yb( 3 He, 3 He(prime) γ) 171 Yb and 171 Yb( 3 He, αγ) 170 Yb reactions. A simultaneous determination of the nuclear level density and the radiative strength function was made. The present data adds to and is consistent with previous results for several other rare earth nuclei. The method will be briefly reviewed and the result from the analysis will be presented. The radiative strength function for 171 Yb is compared to previously published work.

  10. Effects of low dose radiation on kidney function and morphology of diabetic mice

    International Nuclear Information System (INIS)

    Zhang Chi; Li Xiaokun; Gong Shouliang; Meng Tao; Li Cai; Cai Lu

    2010-01-01

    Objective: To study the effect of low dose radiation (LDR) on the kidney function and morphology in C57BL/6J mice with diabetic nephropathy (DN) induced by streptozotocin (STZ) and illuminate the protective function of LDR on kidney damage caused by diabetes mellitus (DM). Methods: The healthy and right age C57BL/6J mice were divided into 4 groups including control, DM, LDR and DM/LDR. The mice in DM and DM/LDR groups were injected intraperitoneally with STZ to set up DM models. The mice in DM/LDR and LDR groups were irradiated with 25 mGy X-rays every other day for 4 weeks. The changes of blood glucose level, urine index level and the morphology of glomerular were detected at 2, 4, 8, 12, 16 weeks after radiation. Results: The blood glucose levels of mice in DM and DM/LDR groups after STZ-induced DM model preparation were higher than those in LDR and control groups (P<0.05). After treated with LDR for 2 weeks, the blood glucose level in DM/LDR group was supressed and significantly lower than that in DM group (P<0.05). Moreover the the change had been kept to 16 weeks. In addition, compared with DM group, the level of urine micro albumin(MALB) in DM/LDR group was decreased and the urine creatinine (Cre) level was increased. Compared with DM group, the morphological results showed that the glomerular mesangial expansion and mesangial cell proliferation were significantly supressed in DM/LDR group (P<0.05). Conclusion: LDR can promote the decease of blood glucose level efficiently, relief the change of kidney function, supress and delay the pathological changes of DN. (authors)

  11. Improvements to a neutral radiation detection and position sensitive process and devices

    International Nuclear Information System (INIS)

    Charpak, Georges; Nguyen, N.H.; Policarpo, Armando.

    1977-01-01

    This invention aims to provide a neutral radiation position sensitive process and device providing a spatial radiation satisfactory for most medical applications and an energy radiation that cannot be reached by gas detectors based on proportional counters or by scintillation counters. Only solid state detectors can compete with respect to energy resolution. The detector described enables large areas to be covered which cannot be reached at accessible costs by solid state detectors. With this aim in view, the invention suggests an incident neutral radiation and position sensitive process, particularly soft gamma and X radiations, whereby photoelectrons are made to form by incident radiation action on gas atoms contained in an enclosure. By means of an electric field, the electrons are diverted towards a space undergoing an electric field high enough in value to create photons by exciting gas atoms and returning them to the de-excited state. The photons are collected, through a transparent window, on a layer of a material for converting such photons into scintillations in the near or visible UV spectrum and the barycentre of the scintillations is positioned on the layer, for instance by photomultipliers or ionization detectors. According to another aspect of the invention, it suggests a detection and position sensitive device comprising (generally downstream of a collimator with a grid of inlet holes) a leak tight containment fitted with an inlet window transparent to incident radiations, filled with a gas producing electrons by interaction with the incident radiation, and fitted with electrodes for generating an electric field to divert the electrons to a space for creating secondary photons [fr

  12. Temporal evaluation of radiation detection system, used by the division of radiation protection of the Navy Technological Centre in Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Gontijo, Rodrigo Modesto Gadelha; Acosta, Clarice de Freitas; Ikari, Andreza Iris R.; Ferreira, Marcio de Oliveira; Alves, Henrique da Silva; Duarte, Marcelo Antonio

    2011-01-01

    This work presents a temporal evaluation of the radiation detection system used by in division of radiation protection of the CTMSP, Sao Paulo, Brazil. About fifty efficiencies results of the system were compiled over the last two years for this purpose. Less than 1% of the standard deviation was found for both portable and fixed detectors, which indicates a significant stability of the detection system used in CTMSP over the period analyzed. (author)

  13. Functionalization of poly (4-vinylpyrrolidone) through γ - radiation induced grafting

    International Nuclear Information System (INIS)

    Pande, C.S.; Ambasta, A.K.; Kumari, Mamta; Sharma, Ajay

    2002-01-01

    Cross-linked poly(N-vinylpyrrolidone) and N-vinylimidazole were mutually irradiated in water under nitrogen with γ-radiations. A detailed study of grafting was made under various reaction parameters. The results have been compared with the grafting done in air. (author)

  14. Systems for detecting and recording hard corpuscular and electromagnetic radiations using a superconducting element

    International Nuclear Information System (INIS)

    Drukier, A.K.; Valette, Claude; Waysand, Georges.

    1975-01-01

    The invention relates to systems for detecting hard X ray or gamma radiations above 5 keV in energy, intended, for example, for gammagraphy by emission in the biological, anatomic and medical fields. It describes systems of the above type which directly give the image of a radiation distribution, that is to say without intermediate processing. Another purpose of the invention is to provide the devices with main memory measuring the radiation distribution, in other words systems that display the said data for as long as the operator deems necessary and that can be reset, that is to say returned to measuring conditions, immediately. The invention makes use of the properties of type I superconductors [fr

  15. Radiation pneumonitis: generalised lung changes detected by radionuclide imaging following focal lung irradiation

    International Nuclear Information System (INIS)

    Ball, D.; Sephton, R.; Irving, L.; Crennan, E.

    1992-01-01

    The usefulness of a nuclear imaging technique as a means of detecting radiation-induced lung injury is examined. The technique involves the patient inhaling modified technegas TM , a gas-like radiotracer which is an ultra fine particulate dispersion. This crosses the alveolar-capillary membrane and the clearance rate of the tracer from the lungs is presumed to reflect membrane permeability. A case of a patient who, after receiving localised radiotherapy and chemotherapy for lung cancer, developed symptoms and signs of radiation pneumonitis is reported. Pre- and post-radiotherapy investigations using the nuclear technique showed acceleration of rates of tracer clearance from both lungs, consistent with generalised changes in alveolar-capillary membrane permeability. It is suggested that the symptoms of radiation pneumonitis may in part result from pathophysiologic changes in nonirradiated lung which may appear radiologically normal. 4 refs., 2 figs

  16. Detection of radiation from a heated and modulated equatorial electrojet current system

    International Nuclear Information System (INIS)

    Lunnen, R.J.; Lee, H.S.; Ferraro, A.J.; Collins, T.W.

    1984-01-01

    In May 1983, ionospheric heating experiments were conducted using the very high frequency radar facility at Lima, Peru. Experiments involving high frequency heating of the ionosphere were successfully conducted during 1982 at Islote, Puerto Rico. These local experiments had characterized the signal radiated from a heated and modulated ionospheric current system near the mid-latitudes. A long-path signal had also been received in September 1982 at Salinas, Puerto Rico from a mid-day equatorial electrojet, heated and modulated by the Jicamarca facility. The authors have investigated the characteristics of the local signal that would be radiated from a strong equatorial electrojet when heated and modulated, and report here that at the geomagnetic equator they were similar to, but less intense than, those observed at Arecibo, Puerto Rico due to parameter differences. This radiation is believed to be the first detected from a heated and modulated equatorial electrojet current system in the Western Hemisphere. (author)

  17. Nick translation detection in situ of cellular DNA strand break induced by radiation

    International Nuclear Information System (INIS)

    Maehara, Y.; Anai, H.; Kusumoto, T.; Sakaguchi, Y.; Sugimachi, K.

    1989-01-01

    DNA strand break in HeLa cells induced by radiation was detected using the in situ nick translation method. The cells were exposed to radiation of 3, 6, 12, 18, and 24 Gy in Lab-Tek tissue culture chamber/slides and were fixed with ethanol/acetic acid on the slide glass. The break sites in DNA were translated artificially in the presence of Escherichia coli DNA polymerase I and [ 3 H]-labeled dTTP. Autoradiographic observation was made of the level of break sites in the DNA. The DNA strand break appeared even with a 3 Gy exposure, increased 8.6 times at 24 Gy compared with the control cells, and this level correlated reciprocally to change in cell viability. This nick translation method provides a rapid in situ assay for determining radiation-induced DNA damage of cultured cells, in a semi-quantitative manner

  18. Insulin-Like Growth Factor-1 Preserves Salivary Gland Function After Fractionated Radiation

    International Nuclear Information System (INIS)

    Limesand, Kirsten H.; Avila, Jennifer L.; Victory, Kerton; Chang, Hui-Hua; Shin, Yoon Joo; Grundmann, Oliver; Klein, Rob R.

    2010-01-01

    Purpose: Radiotherapy for head-and-neck cancer consists of fractionated radiation treatments that cause significant damage to salivary glands leading to chronic salivary gland dysfunction with only limited prevention and treatment options currently available. This study examines the feasibility of IGF-1 in preserving salivary gland function following a fractionated radiation treatment regimen in a pre-clinical model. Methods and Materials: Mice were exposed to fractionated radiation, and salivary gland function and histological analyses of structure, apoptosis, and proliferation were evaluated. Results: In this study, we report that treatment with fractionated doses of radiation results in a significant level of apoptotic cells in FVB mice after each fraction, which is significantly decreased in transgenic mice expressing a constitutively active mutant of Akt1 (myr-Akt1). Salivary gland function is significantly reduced in FVB mice exposed to fractionated radiation; however, myr-Akt1 transgenic mice maintain salivary function under the same treatment conditions. Injection into FVB mice of recombinant insulin-like growth factor-1 (IGF-1), which activates endogenous Akt, suppressed acute apoptosis and preserved salivary gland function after fractionated doses of radiation 30 to 90 days after treatment. FVB mice exposed to fractionated radiation had significantly lower levels of proliferating cell nuclear antigen-positive salivary acinar cells 90 days after treatment, which correlated with a chronic loss of function. In contrast, FVB mice injected with IGF-1 before each radiation treatment exhibited acinar cell proliferation rates similar to those of untreated controls. Conclusion: These studies suggest that activation of IGF-1-mediated pathways before head-and-neck radiation could modulate radiation-induced salivary gland dysfunction and maintain glandular homeostasis.

  19. Setting Performance Objectives for Radiation Detection Systems in Homeland Security Applications - Economic Models

    International Nuclear Information System (INIS)

    Wood, Thomas W.; Bredt, Ofelia P.; Heasler, Patrick G.; Reichmuth, Barbara A.; Milazzo, Matthew D.

    2005-01-01

    This paper develops simple frameworks for cost minimization of detector systems by trading off the costs of failed detection against the social costs of false alarms. A workable system must have a high degree of certainty in detecting real threats and yet impose low social costs. The models developed here use standard measures of detector performance and derive target detection probabilities and false-alarm tolerance specifications as functions of detector performance, threat traffic densities, and estimated costs

  20. Setting Performance Objectives for Radiation Detection Systems in Homeland Security Applications - Economic Models

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Thomas W.; Bredt, Ofelia P.; Heasler, Patrick G.; Reichmuth, Barbara A.; Milazzo, Matthew D.

    2005-04-28

    This paper develops simple frameworks for cost minimization of detector systems by trading off the costs of failed detection against the social costs of false alarms. A workable system must have a high degree of certainty in detecting real threats and yet impose low social costs. The models developed here use standard measures of detector performance and derive target detection probabilities and false-alarm tolerance specifications as functions of detector performance, threat traffic densities, and estimated costs.

  1. Consequences for central nervous system functional state of exposure to ionizing radiation modification with antioxidants

    International Nuclear Information System (INIS)

    Tukalenko, Je.V.; Varets'kij, V.V.; Rakochyi, O.G.; Dmyitryijeva, Yi.R.

    2004-01-01

    Aim: to estimate the pattern of ionizing radiation effects modification by antioxidants using central nervous system functional state indices. The studies were carried out using 84 rats. Beta-carotene and alpha-tocopherol were found to significantly improve conditioned activity indices level of the animals exposed to ionizing radiation and emotional-pain stress

  2. High speed preamplifier circuit, detection electronics, and radiation detection systems therefrom

    Science.gov (United States)

    Riedel, Richard A [Knoxville, TN; Wintenberg, Alan L [Knoxville, TN; Clonts, Lloyd G [Knoxville, TN; Cooper, Ronald G [Oak Ridge, TN

    2010-09-21

    A preamplifier circuit for processing a signal provided by a radiation detector includes a transimpedance amplifier coupled to receive a current signal from a detector and generate a voltage signal at its output. A second amplification stage has an input coupled to an output of the transimpedance amplifier for providing an amplified voltage signal. Detector electronics include a preamplifier circuit having a first and second transimpedance amplifier coupled to receive a current signal from a first and second location on a detector, respectively, and generate a first and second voltage signal at respective outputs. A second amplification stage has an input coupled to an output of the transimpedance amplifiers for amplifying the first and said second voltage signals to provide first and second amplified voltage signals. A differential output stage is coupled to the second amplification stage for receiving the first and second amplified voltage signals and providing a pair of outputs from each of the first and second amplified voltage signals. Read out circuitry has an input coupled to receive both of the pair of outputs, the read out circuitry having structure for processing each of the pair of outputs, and providing a single digital output having a time-stamp therefrom.

  3. Detecting Sonolysis of Polyethylene Glycol Upon Functionalizing Carbon Nanotubes.

    Science.gov (United States)

    Wang, Ruhung; Murali, Vasanth S; Draper, Rockford

    2017-01-01

    Polyethylene glycol (PEG) and related polymers are often used in the solubilization and noncovalent functionalization of carbon nanomaterials by sonication. For example, carbon nanotubes are frequently sonicated with PEG-containing surfactants of the Pluronic ® series or phospholipid-PEG polymers to noncovalently functionalize the nanotubes. However, PEG is very sensitive to degradation upon sonication and the degradation products can be toxic to mammalian cells and to organisms such as zebrafish embryos. It is therefore useful to have a simple and inexpensive method to determine the extent of potential PEG sonolysis, as described in this chapter. Intact PEG polymers and degraded fragments are resolved on sodium dodecyl sulfate polyacrylamide gels by electrophoresis and visualized by staining with barium iodine (BaI 2 ). Digitized images of gels are acquired using a flatbed photo scanner and the intensities of BaI 2 -stained PEG bands are quantified using ImageJ software. Degradation of PEG polymers after sonication is readily detected by the reduction of band intensities in gels compared to those of non-sonicated, intact PEG polymers. In addition, the approach can be used to rapidly screen various sonication conditions to identify those that might minimize PEG degradation to acceptable levels.

  4. Methods for radiation detection and characterization using a multiple detector probe

    Science.gov (United States)

    Akers, Douglas William; Roybal, Lyle Gene

    2014-11-04

    Apparatuses, methods, and systems relating to radiological characterization of environments are disclosed. Multi-detector probes with a plurality of detectors in a common housing may be used to substantially concurrently detect a plurality of different radiation activities and types. Multiple multi-detector probes may be used in a down-hole environment to substantially concurrently detect radioactive activity and contents of a buried waste container. Software may process, analyze, and integrate the data from the different multi-detector probes and the different detector types therein to provide source location and integrated analysis as to the source types and activity in the measured environment. Further, the integrated data may be used to compensate for differential density effects and the effects of radiation shielding materials within the volume being measured.

  5. Summary Report for the Radiation Detection for Nuclear Security Summer School 2012

    Energy Technology Data Exchange (ETDEWEB)

    Runkle, Robert C.; Baciak, James E.; Stave, Jean A.

    2012-08-22

    The Pacific Northwest National Laboratory (PNNL) hosted students from across the United States at the inaugural Radiation Detection for Nuclear Security Summer School from June 11 – 22, 2012. The summer school provided students with a unique understanding of nuclear security challenges faced in the field and exposed them to the technical foundations, analyses, and insight that will be required by future leaders in technology development and implementation. The course heavily emphasized laboratory and field demonstrations including direct measurements of special nuclear material. The first week of the summer school focused on the foundational knowledge required by technology practitioners; the second week focused on contemporary applications. Student evaluations and feedback from student advisors indicates that the summer school achieved its objectives of 1) exposing students to the range of nuclear security applications for which radiation detection is necessary, 2) articulating the relevance of student research into the broader context, and 3) exciting students about the possibility of future careers in nuclear security.

  6. FISH as A method for detection of radiation Induced genetic damage

    International Nuclear Information System (INIS)

    Lakatosova, M.; Holeckova, B.

    2006-01-01

    Fluorescence in situ hybridization (FISH) has been considered as a suitable method for rapid and easy detection of chromosome aberrations. In contrast to the standard conventional staining procedure, this technique enables the detection and specification of stable chromosomal re-arrangements, which are compatible with cellular division and thus, they could be transmitted from common ancestral to next cell generations. FISH chromosome - specific painting probes have been effectively applied for the detection of chromosomal damage after exposure to radiation. During last years, several specific fluorescent labeled probes were performed that allowed precise detection of centromeres, sub-telomeres or other regions (sequences) in genome. Our paper deals with describing of different types of FISH probes and their possibilities for application in radiobiology. (authors)

  7. Possible standoff detection of ionizing radiation using high-power THz electromagnetic waves

    Science.gov (United States)

    Nusinovich, Gregory S.; Sprangle, Phillip; Romero-Talamas, Carlos A.; Rodgers, John; Pu, Ruifeng; Kashyn, Dmytro G.; Antonsen, Thomas M., Jr.; Granatstein, Victor L.

    2012-06-01

    Recently, a new method of remote detection of concealed radioactive materials was proposed. This method is based on focusing high-power short wavelength electromagnetic radiation in a small volume where the wave electric field exceeds the breakdown threshold. In the presence of free electrons caused by ionizing radiation, in this volume an avalanche discharge can then be initiated. When the wavelength is short enough, the probability of having even one free electron in this small volume in the absence of additional sources of ionization is low. Hence, a high breakdown rate will indicate that in the vicinity of this volume there are some materials causing ionization of air. To prove this concept a 0.67 THz gyrotron delivering 200-300 kW power in 10 microsecond pulses is under development. This method of standoff detection of concealed sources of ionizing radiation requires a wide range of studies, viz., evaluation of possible range, THz power and pulse duration, production of free electrons in air by gamma rays penetrating through container walls, statistical delay time in initiation of the breakdown in the case of low electron density, temporal evolution of plasma structure in the breakdown and scattering of THz radiation from small plasma objects. Most of these issues are discussed in the paper.

  8. Fast microwave detection system for coherent synchrotron radiation study at KEK: Accelerator test facility

    International Nuclear Information System (INIS)

    Aryshev, A.; Araki, S.; Karataev, P.; Naito, T.; Terunuma, N.; Urakawa, J.

    2007-01-01

    A fast room temperature microwave detection system based on the Schottky Barrier-diode detector was created at the KEK ATF (Accelerator Test Facility). It was tested using Coherent Synchrotron Radiation (CSR) generated by the 1.28 GeV electron beam in the damping ring. The speed performance of the detection system was checked by observing the CSR from a multi-bunch (2.8 ns bunch separation time) beam. The theoretical estimations of CSR power yield from an edge of bending magnet as well as new injection tuning method are presented. A very high sensitivity of CSR power yield to the longitudinal electron distribution in a bunch is discussed

  9. Function-based Biosensor for Hazardous Waste Toxin Detection

    Energy Technology Data Exchange (ETDEWEB)

    James J Hickman

    2008-07-09

    There is a need for new types of toxicity sensors in the DOE and other agencies that are based on biological function as the toxins encountered during decontamination or waste remediation may be previously unknown or their effects subtle. Many times the contents of the environmental waste, especially the minor components, have not been fully identified and characterized. New sensors of this type could target unknown toxins that cause death as well as intermediate levels of toxicity that impair function or cause long term impairment that may eventually lead to death. The primary question posed in this grant was to create an electronically coupled neuronal cellular circuit to be used as sensor elements for a hybrid non-biological/biological toxin sensor system. A sensor based on the electrical signals transmitted between two mammalian neurons would allow the marriage of advances in solid state electronics with a functioning biological system to develop a new type of biosensor. Sensors of this type would be a unique addition to the field of sensor technology but would also be complementary to existing sensor technology that depends on knowledge of what is to be detected beforehand. We integrated physics, electronics, surface chemistry, biotechnology, and fundamental neuroscience in the development of this biosensor. Methods were developed to create artificial surfaces that enabled the patterning of discrete cells, and networks of cells, in culture; the networks were then aligned with transducers. The transducers were designed to measure electromagnetic fields (EMF) at low field strength. We have achieved all of the primary goals of the project. We can now pattern neurons routinely in our labs as well as align them with transducers. We have also shown the signals between neurons can be modulated by different biochemicals. In addition, we have made another significant advance where we have repeated the patterning results with adult hippocampal cells. Finally, we

  10. [Detection of endotoxins of Gram-negative bacteria on the basis of electromagnetic radiation frequency spectrum].

    Science.gov (United States)

    Likhoded, V G; Kuleshova, N V; Sergieva, N V; Konev, Iu V; Trubnikova, I A; Sudzhian, E V

    2007-01-01

    Method of Gram-negative bacteria endotoxins detection on the basis of their own spectrum of electromagnetic radiation frequency was developed. Frequency spectrum typical for chemotype Re glycolipid, which is a part of lypopolysaccharides in the majority of Gram-negative bacteria, was used. Two devices--"Mini- Expert-DT" (manufactured by IMEDIS, Moscow) and "Bicom" (manufactured by Regumed, Germany)--were used as generators of electromagnetic radiation. Detection of endotoxin using these devices was performed by electropuncture vegetative resonance test. Immunoenzyme reaction with antibodies to chemotype Re glycolipid was used during analysis of preparations for assessment of resonance-frequency method specificity. The study showed that resonance-frequency method can detect lypopolysaccharides of different enterobacteria in quantities up to 0.1 pg as well as bacteria which contain lypopolysaccharides. At the same time, this method does not detect such bacteria as Staphylococcus aureus, Bifidobacterium spp., Lactobacillus spp., and Candida albicans. The method does not require preliminary processing of blood samples and can be used for diagnostics of endotoxinemia, and detection of endotoxins in blood samples or injection solutions.

  11. Photostimulated luminescence detection and radiation effects on cinnamon (Cinnamomum zeylanicum) spice

    International Nuclear Information System (INIS)

    Marcazzó, J.; Sanchez-Barrera, C.E.; Urbina-Zavala, A.; Cruz-Zaragoza, E.

    2015-01-01

    The increase of disease borne pathogens in foods has promoted the use of new technologies in order to eliminate these pathogen microorganisms and extend the shelf-life of the foodstuffs. In particular, Cinnamon (Cinnamomum zeylanicum) contains an important number of pathogen microorganisms and it is frequently sterilized by gamma radiation. However, it is important to develop the detection methods for irradiated food in order to keep the dose control and also to analyze the radiation effects in their chemical property. This work reports (i) the photostimulated luminescence (PSL) detection of irradiated cinnamon and thermoluminescence (TL) detection of the inorganic polymineral fraction separated from this spice, and (ii) the proximate chemical analysis carried out on fat, protein and dietetic fiber contents. The detection limits using the PSL and TL methods were 500 Gy and 10 Gy, respectively, and the fat content was increased significantly with the gamma dose that could be related to the lipid oxidation in the cinnamon. - Highlights: • Samples of cinnamon (Cinnamomum zeylanicum) were studied by TL and PSL methods. • The cinnamon was detected as irradiated at a dose of 500 Gy using PSL. • TL method shows an excellent linear response for doses lesser than 500 Gy. • A proximate chemical analysis was carried out on fat, protein and dietetic fiber. • The TL and PSL responses can be used for dose control in commercial cinnamon

  12. Utilization of photoconductive gain in a-Si:H devices for radiation detection

    International Nuclear Information System (INIS)

    Lee, H.K.; Drewery, J.S.; Hong, W.S.; Jing, T.; Kaplan, S.N.; Perez-Mendez, V.

    1995-05-01

    The photoconductive gain mechanism in a-Si:H was investigated in connection with applications to radiation detection. Various device types such as p-i-n, n-i-n and n-i-p-i-n structures were fabricated and tested. Photoconductive gain was measured in two time scales: one for short pulses of visible light ( 2 . Various gain results are discussed in terms of the device structure, applied bias and dark current

  13. The EPR detection of foods preserved with the use of ionizing radiation

    Science.gov (United States)

    Stachowicz, W.; Burlińska, G.; Michalik, J.; Dziedzic-Gocławska, A.; Ostrowski, K.

    1995-02-01

    Solid constituents extracted from irradiated foods have been examined by the epr (esr) spectroscopy. It has been proved that some epr active species produced by radiation in foods are specific and stable enough to be used for the detection of irradiation treatment. The most promising results have been obtained with bones extracted from frozen raw meat (beef, pork, poultry and fish), with seeds of fruits (dates and figs), with dried mushrooms, gelatin and macaroni.

  14. EPR spectroscopy for the detection of foods treated with ionising radiation

    International Nuclear Information System (INIS)

    Stachowicz, W.; Burlinska, G.; Michalik, J.; Dziedzic-Goclawska, A.; Ostrowski, K.

    1996-01-01

    The advantage of electron paramagnetic resonance spectroscopy (EPR or ESR) as a tool for the control of irradiated food lies in its sensitivity and accuracy. Ionising radiation produces, in irradiated materials, paramagnetic species of different kinds, i.e. radicals, radical-ions and paramagnetic centres, which can be measured by EPR but most of them are not stable enough to be used for the detection of irradiation. It is because radiation-induced paramagnetic species are thermodynamically less stable than surrounding molecules and take part in fast radiolytic reactions leading to the formation of final diamagnetic products that they are not detectable by the EPR method. Most of organic radicals produced by radiation in the liquid phase ae unstable but if the unpaired electron is incorporated into the complex polymeric system as in peptides and polysaccharides and is structurally isolated from the water, its stability is markedly increased. Since 1954 it is known that ionising radiation produces paramagnetic entities in biological materials, cells and tissues and some are stable enough to be observed by EPR spectroscopy at room temperature. The present paper describes and discusses that part of results obtained by this group during the period of ADMIT activity (1989-94) which are original and may be useful to those who will be working in the near future on the development of uniform control systems for the detection of irradiated food. The intention was to focus attention on these facts and data which influence the certainty of the detection in both positive and negative manner. (author)

  15. Discrete Event Simulation Model of the Polaris 2.1 Gamma Ray Imaging Radiation Detection Device

    Science.gov (United States)

    2016-06-01

    release; distribution is unlimited DISCRETE EVENT SIMULATION MODEL OF THE POLARIS 2.1 GAMMA RAY IMAGING RADIATION DETECTION DEVICE by Andres T...ONLY (Leave blank) 2. REPORT DATE June 2016 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE DISCRETE EVENT SIMULATION MODEL...modeled. The platform, Simkit, was utilized to create a discrete event simulation (DES) model of the Polaris. After carefully constructing the DES

  16. Method of detection of transition radiation by wire chambers operating in self-quenching streamer mode

    International Nuclear Information System (INIS)

    Akopdzhanov, G.A.; Bityukov, S.I.; Dzhelyadin, R.I.; Zaitsev, A.M.; Lapin, V.V.; Saraikin, A.I.

    1984-01-01

    A method for detecting X-ray transition radiation against the background of the signal from relativistic charged particles is suggested that is based on the use of peculiarities of the development of self-queenching streamer mode. The self-qunching streamer discharge in the Xe + isobutane mixture is experimentally registered. The effect of separation of signals from the relativistic particle and from soft X-ray, is obtained

  17. New silicon photodiodes for detection of the 1064nm wavelength radiation

    Science.gov (United States)

    Wegrzecki, Maciej; Piotrowski, Tadeusz; Puzewicz, Zbigniew; Bar, Jan; Czarnota, Ryszard; Dobrowolski, Rafal; Klimov, Andrii; Kulawik, Jan; Kłos, Helena; Marchewka, Michał; Nieprzecki, Marek; Panas, Andrzej; Seredyński, Bartłomiej; Sierakowski, Andrzej; Słysz, Wojciech; Synkiewicz, Beata; Szmigiel, Dariusz; Zaborowski, Michał

    2016-12-01

    In this paper a concept of a new bulk structure of p+-υ-n+ silicon photodiodes optimized for the detection of fast-changing radiation at the 1064 nm wavelength is presented. The design and technology for two types of quadrant photodiodes, the 8-segment photodiode and the 32-element linear photodiode array that were developed according to the concept are described. Electric and photoelectric parameters of the photodiodes mentioned above are presented.

  18. General trend and local variations of neutron resonance cascade gamma-decay radiative strength functions

    International Nuclear Information System (INIS)

    Sukhovoj, A.M.; Furman, W.I.; Khitrov, V.A.; Jovancevic, N.

    2012-01-01

    A new hypothesis on the dependence of the form of the radiative strength functions of electric and magnetic dipole gamma transitions in a heated nucleus on the excited level density was suggested and tested experimentally. For this purpose, the region of possible values of random values of the level density and radiative strength functions which precisely reproduced experimental intensity of two-step cascades for 41 nuclei from 40K to 200Hg was determined. It was obtained that the suggested hypothesis can provide the maximal increase of radiative strength functions values by order of magnitude in comparison with existing notations as a result of collective effects enhancement. This result points to the necessity to take into account this possibility in existing and future models of radiative strength functions

  19. A new radiative transfer scattering phase function discretisation approach with inherent energy conservation

    CSIR Research Space (South Africa)

    Roos, TH

    2014-06-01

    Full Text Available large sphere scattering phase function distributions of interest for packed bed radiative heat transfer: the analytic distribution for a diffusely reflecting sphere (a backscattering test case) and the distribution for a transparent sphere (n = 1...

  20. Discrete Green's Theorem, Green's Functions and Stable Radiative FDTD Boundary Conditions

    NARCIS (Netherlands)

    Arnold, J.M.; Hon, de B.P.

    2007-01-01

    We propose a radiative boundary condition for the discrete-grid formulation of Helmholtz’ equation, based on rational approximation in the frequency domain of a Green’s function for the discretised system. This boundary condition is free from instabilities.

  1. Highly Sensitive Detection of UV Radiation Using a Uranium Coordination Polymer.

    Science.gov (United States)

    Liu, Wei; Dai, Xing; Xie, Jian; Silver, Mark A; Zhang, Duo; Wang, Yanlong; Cai, Yawen; Diwu, Juan; Wang, Jian; Zhou, Ruhong; Chai, Zhifang; Wang, Shuao

    2018-02-07

    The accurate detection of UV radiation is required in a wide range of chemical industries and environmental or biological related applications. Conventional methods taking advantage of semiconductor photodetectors suffer from several drawbacks such as sophisticated synthesis and manufacturing procedure, not being able to measure the accumulated UV dosage as well as high defect density in the material. Searching for new strategies or materials serving as precise UV dosage sensor with extremely low detection limit is still highly desirable. In this work, a radiation resistant uranium coordination polymer [UO 2 (L)(DMF)] (L = 5-nitroisophthalic acid, DMF = N,N-dimethylformamide, denoted as compound 1) was successfully synthesized through mild solvothermal method and investigated as a unique UV probe with the detection limit of 2.4 × 10 -7 J. On the basis of the UV dosage dependent luminescence spectra, EPR analysis, single crystal structure investigation, and the DFT calculation, the UV-induced radical quenching mechanism was confirmed. Importantly, the generated radicals are of significant stability which offers the opportunity for measuring the accumulated UV radiation dosage. Furthermore, the powder material of compound 1 was further upgraded into membrane material without loss in luminescence intensity to investigate the real application potentials. To the best of our knowledge, compound 1 represents the most sensitive coordination polymer based UV dosage probe reported to date.

  2. A promising new mechanism of ionizing radiation detection for positron emission tomography: modulation of optical properties

    Science.gov (United States)

    Tao, Li; Daghighian, Henry M.; Levin, Craig S.

    2016-11-01

    Using conventional scintillation detection, the fundamental limit in positron emission tomography (PET) time resolution is strongly dependent on the inherent temporal variances generated during the scintillation process, yielding an intrinsic physical limit for the coincidence time resolution of around 100 ps. On the other hand, modulation mechanisms of the optical properties of a material exploited in the optical telecommunications industry can be orders of magnitude faster. In this paper we borrow from the concept of optics pump-probe measurement to for the first time study whether ionizing radiation can produce modulations of optical properties, which can be utilized as a novel method for radiation detection. We show that a refractive index modulation of approximately 5× {{10}-6} is induced by interactions in a cadmium telluride (CdTe) crystal from a 511 keV photon source. Furthermore, using additional radionuclide sources, we show that the amplitude of the optical modulation signal varies linearly with both the detected event rate and average photon energy of the radiation source.

  3. Evaluation of the Detection Efficiency of LYSO Scintillator in the Fiber-Optic Radiation Sensor

    Directory of Open Access Journals (Sweden)

    Chan Hee Park

    2014-01-01

    Full Text Available The aim of this study was to develop and evaluate fiber-optic sensors for the remote detection of gamma rays in areas that are difficult to access, such as a spent fuel pool. The fiber-optic sensor consists of a light-generating probe, such as scintillators for radiation detection, plastic optical fibers, and light-measuring devices, such as PMT. The (Lu,Y2SiO5:Ce(LYSO:Ce scintillator was chosen as the light-generating probe. The (Lu,Y2SiO5:Ce(LYSO:Ce scintillator has higher scintillation efficiency than the others and transmits light well through an optical fiber because its refraction index is similar to the refractive index of the optical fiber. The fiber-optic radiation sensor using the (Lu,Y2SiO5:Ce(LYSO:Ce scintillator was evaluated in terms of the detection efficiency and reproducibility for examining its applicability as a radiation sensor.

  4. Radiation protection program for early detection of breast cancer in a mammography facility

    International Nuclear Information System (INIS)

    Mariana, Villagomez Casimiro; Cesar, Ruiz Trejo; Ruby, Espejo Fonseca

    2014-01-01

    Mammography is the best tool for early detection of Breast Cancer. In this diagnostic radiology modality it is necessary to establish the criteria to ensure the proper use and operation of the equipment used to obtain mammographic images in order to contribute to the safe use of ionizing radiation. The aim of the work was to implement at FUCAM-AC the radiation protection program which must be established for patients and radiation workers according to Mexican standards [1–4]. To achieve this goal, radiation protection and quality control manuals were elaborated [5]. Furthermore, a quality control program (QCP) in the mammography systems (analog/digital), darkroom included, has been implemented. Daily sensitometry, non-variability of the image quality, visualizing artifacts, revision of the equipment mechanical stability, compression force and analysis of repetition studies are some of the QCP routine tests that must be performed by radiological technicians of this institution as a set of actions to ensure the protection of patients. Image quality and patients dose assessment were performed on 4 analog equipment installed in 2 mobile units. In relation to dose assessment, all equipment passed the acceptance criteria (<3 mGy per projection). The image quality test showed that most images (70%)– presented artifacts. A brief summary of the results of quality control tests applied to the equipment and film processor are presented. To maintain an adequate level of quality and safety at FUCAM-AC is necessary that the proposed radiation protection program in this work is applied

  5. Radiation protection program for early detection of breast cancer in a mammography facility

    Energy Technology Data Exchange (ETDEWEB)

    Mariana, Villagomez Casimiro, E-mail: marjim10-66@ciencias.unam.mx, E-mail: cesar@fisica.unam.mx; Cesar, Ruiz Trejo, E-mail: marjim10-66@ciencias.unam.mx, E-mail: cesar@fisica.unam.mx [Instituto de Física, UNAM. Cd. Universitaria, CP 04510 (Mexico); Ruby, Espejo Fonseca [Instituto de Enfermedades de la Mama FUCAM-AC, CP 04980 (Mexico)

    2014-11-07

    Mammography is the best tool for early detection of Breast Cancer. In this diagnostic radiology modality it is necessary to establish the criteria to ensure the proper use and operation of the equipment used to obtain mammographic images in order to contribute to the safe use of ionizing radiation. The aim of the work was to implement at FUCAM-AC the radiation protection program which must be established for patients and radiation workers according to Mexican standards [1–4]. To achieve this goal, radiation protection and quality control manuals were elaborated [5]. Furthermore, a quality control program (QCP) in the mammography systems (analog/digital), darkroom included, has been implemented. Daily sensitometry, non-variability of the image quality, visualizing artifacts, revision of the equipment mechanical stability, compression force and analysis of repetition studies are some of the QCP routine tests that must be performed by radiological technicians of this institution as a set of actions to ensure the protection of patients. Image quality and patients dose assessment were performed on 4 analog equipment installed in 2 mobile units. In relation to dose assessment, all equipment passed the acceptance criteria (<3 mGy per projection). The image quality test showed that most images (70%)– presented artifacts. A brief summary of the results of quality control tests applied to the equipment and film processor are presented. To maintain an adequate level of quality and safety at FUCAM-AC is necessary that the proposed radiation protection program in this work is applied.

  6. Radiation protection program for early detection of breast cancer in a mammography facility

    Science.gov (United States)

    Villagomez Casimiro, Mariana; Ruiz Trejo, Cesar; Espejo Fonseca, Ruby

    2014-11-01

    Mammography is the best tool for early detection of Breast Cancer. In this diagnostic radiology modality it is necessary to establish the criteria to ensure the proper use and operation of the equipment used to obtain mammographic images in order to contribute to the safe use of ionizing radiation. The aim of the work was to implement at FUCAM-AC the radiation protection program which must be established for patients and radiation workers according to Mexican standards [1-4]. To achieve this goal, radiation protection and quality control manuals were elaborated [5]. Furthermore, a quality control program (QCP) in the mammography systems (analog/digital), darkroom included, has been implemented. Daily sensitometry, non-variability of the image quality, visualizing artifacts, revision of the equipment mechanical stability, compression force and analysis of repetition studies are some of the QCP routine tests that must be performed by radiological technicians of this institution as a set of actions to ensure the protection of patients. Image quality and patients dose assessment were performed on 4 analog equipment installed in 2 mobile units. In relation to dose assessment, all equipment passed the acceptance criteria (radiation protection program in this work is applied.

  7. Counter-Radiation Balm and its Medical Properties at Radiation Injuries and Functional Disorders in Gastrointestinal Tract

    International Nuclear Information System (INIS)

    Melkadze, R.; Shalamberidze, M.

    2006-01-01

    It has been shown that the Counter-Radiation Balm (CRB) is fairly effective in normalization of secretory phenomena and eubiotic state of the digestive tract in conditions of their functional disorders induced by various causes. The CRB has normalizing effect on an intestional flora during experimental dysbacterioses, induced with irradiation and starvation. This holds true in both bone marrow- and mixed patterns of acute radiation disease (ARD). The CRB somewhat decreases a toxic constituent of ARD, increases colonization resistance of the intestine to external microbial invasions and precludes extension of intestinal area for conditionally-pathogene flora. (author)

  8. Application of radiation-induced graft polymerization to preparation of functional materials

    International Nuclear Information System (INIS)

    Sugo, Takanobu

    2010-01-01

    Radiation-induced graft polymerization is a powerful method for appending various functionalities onto existing fabrics, nonwoven fabrics, fibers, membranes, and beads while maintaining the shape and mechanical strength. By using this method, the author has developed and commercialized functional polymeric materials over 45 years. The materials produced by the fruits of radiation chemistry contributed to the improvement of our lives and environments and the collection of rare metal resources. (author)

  9. The Use of Radiation Detectors in Medicine: Radiation Detectors for Functional Imaging (2/3)

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    The development of radiation detectors in the field of nuclear and particle physics has had a terrific impact in medical imaging since this latter discipline took off in late ’70 with the invention of the CT scanners. The massive use in High Energy Physics of position sensitive gas detectors, of high Z and high density scintillators coupled to Photomultiplier (PMT) and Position Sensitive Photomultipliers (PSPMT), and of solid state detectors has triggered during the last 30 years a series of novel applications in Medical Imaging with ionizing radiation. The accelerated scientific progression in genetics and molecular biology has finally generated what it is now called Molecular Imaging. This field of research presents additional challenges not only in the technology of radiation detector, but more and more in the ASIC electronics, fast digital readout and parallel software. In this series of three lectures I will try to present how high energy physics and medical imaging development have both benefited by t...

  10. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  11. Radiation-related caries assessment through the International Caries Detection and Assessment System and the Post-Radiation Dental Index.

    Science.gov (United States)

    Palmier, Natalia Rangel; Ribeiro, Ana Carolina Prado; Fonsêca, Jéssica Montenegro; Salvajoli, João Victor; Vargas, Pablo Agustin; Lopes, Marcio Ajudarte; Brandão, Thaís Bianca; Santos-Silva, Alan Roger

    2017-12-01

    Although radiation-related caries (RRC) are a well-known toxicity of head and neck radiotherapy, a clinical classification system for RRC has not yet been clinically validated. Therefore, the aim of this study was to assess whether the International Caries Detection and Assessment System (ICDAS) and the Post-Radiation Dental Index (PRDI) were viable methods for the assessment of RRC. Clinicopathologic data and intraoral digital photographs of 60 patients (833 teeth) affected by RRC were assessed and classified according to the ICDAS and PRDI criteria. A total of 814 (97.7%) teeth presented RRC lesions ranging from early stage to complete tooth destruction. Mean scores for the whole sample were 5 for ICDAS and 3 for PRDI, indicating that RRC were diagnosed predominately in late stages. ICDAS and PRDI criteria underestimate the clinical expressivity of RRC by not including the whole qualitative clinical spectrum of RRC, such as enamel cracks, delamination, dental crown amputation, surface color alterations, and atypical lesions topography (incisal/cuspal caries). ICDAS and PRDI may not be considered viable for the assessment of RRC. The development of a specific clinical classification system is urgently needed to help clinicians recognize the peculiar patterns of RRC, particularly in incipient cases. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Impact of ultraviolet-B radiation on planktonic fish larvae: Alteration of the osmoregulatory function

    Energy Technology Data Exchange (ETDEWEB)

    Sucre, Elliott, E-mail: elliott.sucre@univ-montp2.fr [AEO Team (Adaptation Ecophysiologique et Ontogenese), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc092, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Vidussi, Francesca [RESEAUX Team (Reseaux Planctoniques et Changement Environnemental), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc093, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Mostajir, Behzad [RESEAUX Team (Reseaux Planctoniques et Changement Environnemental), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc093, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Centre d' ecologie marine experimentale MEDIMEER (Mediterranean centre for Marine Ecosystem Experimental Research), Universite Montpellier 2-CNRS (UMS 3301), Station Mediterraneenne de l' Environnement Littoral, MEDIMEER, 2 Rue des Chantiers, 34200 Sete (France); Charmantier, Guy; Lorin-Nebel, Catherine [AEO Team (Adaptation Ecophysiologique et Ontogenese), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc092, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France)

    2012-03-15

    Coastal marine ecosystems are submitted to variations of several abiotic and biotic parameters, some of them related to global change. Among them the ultraviolet-B (UV-B) radiation (UVBR: 280-320 nm) may strongly impact planktonic fish larvae. The consequences of an increase of UVBR on the osmoregulatory function of Dicentrarchus labrax larvae have been investigated in this study. In young larvae of D. labrax, as in other teleosts, osmoregulation depends on tegumentary ion transporting cells, or ionocytes, mainly located on the skin of the trunk and of the yolk sac. As early D. labrax larvae passively drift in the top water column, ionocytes are exposed to solar radiation. The effect of UVBR on larval osmoregulation in seawater was evaluated through nanoosmometric measurements of the blood osmolality after exposure to different UV-B treatments. A loss of osmoregulatory capability occured in larvae after 2 days of low (50 {mu}W cm{sup -2}: 4 h L/20 h D) and medium (80 {mu}W cm{sup -2}: 4 h L/20 h D) UVBR exposure. Compared to control larvae kept in the darkness, a significant increase in blood osmolality, abnormal behavior and high mortalities were detected in larvae exposed to UVBR from 2 days on. At the cellular level, an important decrease in abundance of tegumentary ionocytes and mucous cells was observed after 2 days of exposure to UVBR. In the ionocytes, two major osmoeffectors were immunolocalized, the Na{sup +}/K{sup +}-ATPase and the Na{sup +}/K{sup +}/2Cl{sup -} cotransporter. Compared to controls, the fluorescent immunostaining was lower in UVBR-exposed larvae. We hypothesize that the impaired osmoregulation in UVBR-exposed larvae originates from the lower number of tegumentary ionocytes and mucous cells. This alteration of the osmoregulatory function could negatively impact the survival of young larvae at the surface water exposed to UVBR.

  13. Characterization of the functional domains of the natriuretic peptide receptor/guanylate cyclase by radiation inactivation

    International Nuclear Information System (INIS)

    Tremblay, J.; Huot, C.; Koch, C.; Potier, M.

    1991-01-01

    Radiation inactivation has been used to evaluate the molecular size of domains responsible for atrial natriuretic peptide (ANP)-binding and cyclase functions of the ANP receptor/guanylate cyclase. Two types of inactivation curves were observed for cyclase function in both adrenal cortex and aortic smooth muscle cells: (1) biphasic with enhanced guanylate cyclase activity after exposure to low radiation doses and (2) linear after preincubation of membrane proteins with 0.5 microM ANP or solubilization with Triton X-100. The existence of an inhibitory component was the simplest model that best explained the types of radiation curves obtained. Activation of guanylate cyclase by ANP or Triton X-100 could occur via the dissociation of this inhibitory component from the catalytic domain. On the other hand, the loss of ANP-binding activity was linear with increasing radiation exposures under basal, ANP treatment, and Triton X-100 solubilization conditions. Radiation inactivation sizes of about 30 kDa for cyclase function, 20 kDa for ANP-binding function, and 90 kDa for inhibitory function were calculated. These studies suggest that the ANP receptor/guanylate cyclase behaves as a multidomain protein. The results obtained by radiation inactivation of the various biological functions of this receptor are compatible with the hypothesis of an intramolecular inhibitory domain repressing the guanylate cyclase catalytic domain within its membrane environment

  14. Functional significance of air trapping detected in moderate asthma

    International Nuclear Information System (INIS)

    Laurent, F.; Latrabe, V.; Raherison, C.; Marthan, R.; Tunon-de-Lara, J.M.

    2000-01-01

    The aim of this study was to evaluate bronchial and lung abnormalities in patients suffering from moderate asthma as defined by international guidelines, with special attention to air trapping on CT in comparison with that detected in smoking and non-smoking normal subjects. Twenty-two patients classified as moderate asthma and control subjects including healthy volunteers, smokers (n = 10) or non-smokers (n = 12) were prospectively explored by high-resolution CT (HRCT) performed at suspended full inspiration and expiration. The same expiratory protocol was performed 15 min after inhalation of 200 μg of salbutamol. Patients underwent pulmonary function tests within the same week and bronchodilator response was assessed following inhalation of salbutamol. Abnormalities of bronchi and lung parenchyma on inspiratory CT and air trapping on expiratory CT, in dependent and non-dependent areas, were assessed and scored semi-quantitatively by two independent observers. Comparison of score mean values between the different groups was performed using Mann-Whitney test and Spearman correlation between CT findings and pulmonary function tests were calculated. Mosaic perfusion was observed in 23 % of asthmatics. Air-trapping scores were significantly higher in asthmatic patients than in non-smoking control subjects (p = 0.003), but not than in smokers. This difference was ascribed to non-dependent zones of the lung for which air-trapping scores were also higher in asthmatic patients (p = 0.003) and in smoking subjects (p = 0.004) than in normal controls. In the asthmatic group, a significant positive correlation was found between airways resistance and bronchial dilatation score (p = 0.01), and between small airways obstruction index and mosaic perfusion score (p = 0.05). In addition, both FEV1 and reversibility of small airways obstruction values correlated with air-trapping score (p = 0.03 and p = 0.007, respectively). No change could be detected in air-trapping score

  15. Gamma Radiation (5-10 Gy) Impairs Neuronal Function in the Guinea Pig Hippocampus

    Science.gov (United States)

    1993-01-01

    Radiation (5-10 Gy) Impairs Neuronal Function in the Guinea Pig Hippocampus TERRY C. PELLMAR AND DENNIS L. LEPINSKI Ph.vsiology Department..Irmned Forces...L. Gamma Radiation ioral effects. Within hours of irradiation with 10 Gy and (5- 10 Gy) Impairs Neuronal Function in the Guinea Pig Hippo- less...acti v- Guinea pigs were exposed to 5 and 10 Gy ’y radiation. Hippo- ity (9) are evident. campal brain slices were isolated 30 min, I day, 3 days and 5

  16. UV radiation and organic matter composition shape bacterial functional diversity in sediments

    Directory of Open Access Journals (Sweden)

    Ellard Roy Hunting

    2013-10-01

    Full Text Available AbstractUV radiation and organic matter (OM composition are known to influence the speciescomposition of bacterioplankton communities. Potential effects of UV radiation onbacterial communities residing in sediments remain completely unexplored to date.However, it has been demonstrated that UV radiation can reach the bottom of shallowwaters and wetlands and alter the OM composition of the sediment, suggesting thatUV radiation may be more important for sediment bacteria than previously anticipated.It is hypothesized here that exposure of shallow OMcontaining sediments to UVradiation induces OMsource dependant shifts in the functional composition ofsediment bacterial communities. This study therefore investigated the combinedinfluence of both UV radiation and OM composition on bacterial functional diversity inlaboratory sediments. Two different organic matter sources, labile and recalcitrantorganic matter (OM, were used and metabolic diversity was measured with BiologGN. Radiation exerted strong negative effects on the metabolic diversity in thetreatments containing recalcitrant OM, more than in treatments containing labile OM.The functional composition of the bacterial community also differed significantlybetween the treatments. Our findings demonstrate that a combined effect of UVradiation and OM composition shapes the functional composition of microbialcommunities developing in sediments, hinting that UV radiation may act as animportant sorting mechanism for bacterial communities and driver for bacterialfunctioning in shallow lakes and wetlands.

  17. Fluorescence in situ hybridisation in chromosome aberration detection in subjects occupationally exposed to ionising radiation

    International Nuclear Information System (INIS)

    Zeljezic, D.; Garaj-Vrhovac, V.

    2005-01-01

    For more than two decades, chromosomal aberration analysis has been used to detect structural chromosomal aberrations as sensitive biodosimeters of occupational exposure to ionising radiation. Its use is also recommended by the World Health Organisation. Changes in chromosome structure detected by that method are considered to be early biomarkers of a possible malignant disease. Aberrations detected by the method are unstable and can be found in the lymphocytes of irradiated personnel only within a limited time after exposure. To detect stable chromosomal aberrations, which persist after exposure, multicolour fluorescent in situ hybridisation has to be used. Using DNA probes labelled with different fluorochromes, it dyes each pair of chromosomes with different colour. Due to the dynamic of unstable aberration formation, chromosomal aberration analysis is more suitable in genome damage assessment of recent exposures. On the other hand, fluorescence in situ hybridisation gives the information on chromosome instability caused by long-term occupational exposure to ionising radiation. Considering the high costs of fluorescence in situ hybridisation and the uncertainty of the result, it should be used in biodosimetry only when it is absolutely necessary.(author)

  18. Functionalized Polymers Prepared by Ionizing Radiation and their Practical Uses

    International Nuclear Information System (INIS)

    Diaa, D.A.H.A.

    2011-01-01

    Trails are made to replace hazardous industrial materials by cleaner and safer ones. In this respect Polyvinyl alcohol/acrylic acid (PVA/AA) micro gel is prepared using ionizing radiation and titanium dioxide (TiO 2 ) was immobilized on its surface. The photo-degradation efficiency against metanil yellow azo dye is studied. Easily recovery and reusability made (PVA/AA)-TiO 2 of great importance in practical use as a photo-catalytic degradation composite, for dye removal from textile waste water. Starch was treated with chlorosulfonic acid; to obtain sulfonated starch. Radiation modification of sulfonated starch/ acrylic acid (SS/AA) hydrogel for possible use as an eco friendly water-retarding agent in the cement industry was investigated. On the other hand, the hydrolysis of sucrose to glucose and fructose by (SS/AA) graft copolymers was also stuided. The catalytic activity of the (SS/AA) copolymers was found to be dependent on the reaction temperature and (SS/AA) graft copolymers compositions

  19. Physiological bases for detecting and predicting photoinhibition of aquatic photosynthesis by PAR and UV radiation

    International Nuclear Information System (INIS)

    Neale, P.J.; Cullen, J.J.; Lesser, M.P.; Melis, A.

    1993-01-01

    stress is usually time dependent (12, 36); the light history of the cells must be known to specify the overall effect. The established method for measuring phytoplankton production, photosynthetic incorporation of 14 C into organic carbon during a12-24 h bottle incubation, may seriously misrepresent irradiance regimes actually experienced by phytoplankton in situ. Further discussion of the interaction of photoinhibition and mixing can be found in (36).We propose that an integrated modeling-sampling approach is needed to define the effects of irradiance stress on productivity in situ. The model should incorporate an optical specification of the underwater irradiance environment, abiological weighting function to account for the wavelength-dependence of photoinhibition of photosynthesis, and a response function of biological action during vertical mixing to account for the differences between static incubations and natural movements of phytoplankton. Recently, excellent progress has been made toward defining the individual components of this model (See also Cullen and Neale, this volume). To verify the model, we need to detect reliably the occurrence of irradiance stress in situ. This is the sampling side of the integrated approach. In particular, we would like to differentiate between the effects of PAR and UV. We propose that such detection can be accomplished by indicator assays (or ''diagnostic markers''). Such assays would involve little or no incubation of samples, so that the measurement corresponds as closely as possible to the physiological state of the phytoplankton at time of sampling.Our objective here is to review selected aspects of irradiance stress at biophysical and molecular levels, and then proceed to examine how that information can be used to design indicator assays of irradiance stress for phytoplankton photosynthesis in situ. The effects of PAR and UV at the cellular level and the use of in vivo fluorescence and molecular probes

  20. Procedures and techniques for monitoring the radiation detection, signalization and alarm systems in the centralized ambience monitoring systems of the basic nuclear facilities of the CEN Saclay

    International Nuclear Information System (INIS)

    Andre, J.-J.; Drouet, J.; Leblanc, P.

    1979-01-01

    After referring to the regulations governing the 'systematic ambience monitoring' in the basic nuclear facilities, the main radiation detection, signalization and alarm devices existing at present in these facilities of the Saclay Nuclear Study Centre are described. The analysis of the operating defects of the measuring channels and detection possibilities leads to the anomalies being classified in two separate groups: the anomalies of the logical 'all or nothing' type of which all the possible origins are integrated into a so-called 'continuity' line and the evolutive anomalies of various origins corresponding to poor functioning extending possibly to a complete absence of signal. The techniques for testing the detection devices of the radiation monitoring board set up in the 'Departement de Rayonnements' at the Saclay Nuclear Study Centre are also described [fr

  1. System for visualizing a body by detecting the radiation of a tracer contained therein

    International Nuclear Information System (INIS)

    Vacher, Jacques.

    1980-01-01

    This invention concerns a device for visualizing a body by detecting the radiation from a tracer composed of positron emitters contained in this body. This system has a particular application in tomography and hence for the visualization of a group of organs in a given cross-section. It includes: - detection cells positioned on both sides of the body to detect the gamma particles delivered by each positron emitter, in two opposite directions, - devices for localizing cells opposed in pairs, on both sides of the body, each opposed pair of cells being located on a straight line passing through a positron emitter, - systems for coding the localization of these pairs of opposed cells, - systems for memorizing these coded localization signals, - facilities for processing these stored signals, - visual displays controlled by the data processing units, to show the image of the body as from the various coded and memorized signals [fr

  2. Combination radiation-adriamycin therapy: renoprival growth, functional and structural effects in the immature mouse

    International Nuclear Information System (INIS)

    Donaldson, S.S.; Moskowitz, P.S.; Canty, E.L.; Fajardo, L.F.

    1980-01-01

    The normal tissue effects of radiation-adriamycin combination therapy were studied in the renoprival weanling mouse in an attempt to determine whether compensatory renal growth inhibition from radiation and chemotherapy could be associated with structural or functional abnormalities. Weanling BLc/sub Fl/ mice underwent unilateral nephrectomy, then single fraction renal irradiation, LD 1/21 doses of adriamycin in 5 daily doses, or combination therapy with radiation and adriamycin. Animals were sacrificed at 3, 12, and 24 weeks. Compensatory renal growth, body growth, serum blood urea nitrogen (BUN), and renal morphology by light microscopy were evaluated. Significant compensatory renal growth inhibition from radiation-adriamycin therapy exceeded that produced by adriamycin alone and radiation alone, at all time periods (p < 0.005). Body growth inhibition from radiation-adriamycin therapy or adriamycin alone significantly exceeded that produced by radiation alone (p < 0.005). Kidney and body growth inhibition from radiation-adriamycin therapy was proportionately severe. Kidney growth inhibition proportionately exceeded body growth inhibition with radiation alone; body growth inhibition proportionately exceeded kidney growth inhibition with adriamycin alone. Comparable azotemia developed by 24 weeks in both the radiation alone (p < .005) and radiation-adriamycin animals (p < 0.005), but not in the adriamycin only animals. Morphologic alterations consisting of increased glomerular density, tubular atrophy, and stromal fibrosis occurred with greater severity in the radiation-adriamycin animals than in the radiation only animals by 24 weeks; no alterations were seen in the adriamycin only animals. Using histologic criteria 750 rad plus adriamycin produced comparable injury as seen with 1000 rad alone, thus adriamycin produced an apparent dose-modifying factor of 1.33

  3. Feasibility of OCT to detect radiation-induced esophageal damage in small animal models (Conference Presentation)

    Science.gov (United States)

    Jelvehgaran, Pouya; Alderliesten, Tanja; Salguero, Javier; Borst, Gerben; Song, Ji-Ying; van Leeuwen, Ton G.; de Boer, Johannes F.; de Bruin, Daniel M.; van Herk, Marcel B.

    2016-03-01

    Lung cancer survival is poor and radiotherapy patients often suffer serious treatment side effects. The esophagus is particularly sensitive leading to reduced food intake or even fistula formation. Only few direct techniques exist to measure radiation-induced esophageal damage, for which knowledge is needed to improve the balance between risk of tumor recurrence and complications. Optical coherence tomography (OCT) is a minimally-invasive imaging technique that obtains cross-sectional, high-resolution (1-10µm) images and is capable of scanning the esophageal wall up to 2-3mm depth. In this study we investigated the feasibility of OCT to detect esophageal radiation damage in mice. In total 30 mice were included in 4 study groups (1 main and 3 control groups). Mice underwent cone-beam CT imaging for initial setup assessment and dose planning followed by single-fraction dose delivery of 4, 10, 16, and 20Gy on 5mm spots, spaced 10mm apart. Mice were repeatedly imaged using OCT: pre-irradiation and up to 3 months post-irradiation. The control groups received either OCT only, irradiation only, or were sham-operated. We used histopathology as gold standard for radiation-induced damage diagnosis. The study showed edema in both the main and OCT-only groups. Furthermore, radiation-induced damage was primarily found in the highest dose region (distal esophagus). Based on the histopathology reports we were able to identify the radiation-induced damage in the OCT images as a change in tissue scattering related to the type of induced damage. This finding indicates the feasibility and thereby the potentially promising role of OCT in radiation-induced esophageal damage assessment.

  4. Development of a homogeneous pulse shape discriminating flow-cell radiation detection system

    International Nuclear Information System (INIS)

    Hastie, K.H.; DeVol, T.A.; Fjeld, R.A.

    1999-01-01

    A homogeneous flow-cell radiation detection system which utilizes coincidence counting and pulse shape discrimination circuitry was assembled and tested with five commercially available liquid scintillation cocktails. Two of the cocktails, Ultima Flo (Packard) and Mono Flow 5 (National Diagnostics) have low viscosities and are intended for flow applications; and three of the cocktails, Optiphase HiSafe 3 (Wallac), Ultima Gold AB (Packard), and Ready Safe (Beckman), have higher viscosities and are intended for static applications. The low viscosity cocktails were modified with 1-methylnaphthalene to increase their capability for alpha/beta pulse shape discrimination. The sample loading and pulse shape discriminator setting were optimized to give the lowest minimum detectable concentration for methylnaphthalenein a 30 s count time. Of the higher viscosity cocktails, Optiphase HiSafe 3 had the lowest minimum detectable activities for alpha and beta radiation, 0.2 and 0.4 Bq/ml for 233 U and 90 Sr/ 90 Y, respectively, for a 30 s count time. The sample loading was 70% and the corresponding alpha/beta spillover was 5.5%. Of the low viscosity cocktails, Mono Flow 5 modified with 2.5% (by volume) 1-methylnaphthalene resulted in the lowest minimum detectable activities for alpha and beta radiation; 0.3 and 0.5 Bq/ml for 233 U and 90 Sr/ 90 Y, respectively, for a 30 s count time. The sample loading was 50%, and the corresponding alpha/beta spillover was 16.6%. HiSafe 3 at a 10% sample loading was used to evaluate the system under simulated flow conditions

  5. Detection of dark-matter-radiation of stars during visible sun eclipses

    International Nuclear Information System (INIS)

    Volkamer, Klaus

    2003-01-01

    Recently a so-far unknown form of quantized, cold dark matter was detected on a laboratory scale which shows a complementary structure as compared to known forms of matter. From the experiments results that the observed quanta of the new type of matter as integer multiples of the Planck mass (mp = n · √((h·c)/((2 · π · G))) = n 0 21.77 μg, with n = 1, 2, 3 etc.) exhibit a spatially extended 'field-like' structure ranging over distances of centimetres or more, opposite to the 'point-like' structure of the known elementary particles of the standard model. Association of quanta of the new form of 'soft' (or subtle) matter to clusters was observed, as well as re-clustering after absorption. Thus, between such quanta a physical interaction must exist. In addition, the new form of matter shows at least two interactions with normal matter, a gravitational one due to its real mass content and a so-far unknown 'topological', i.e. form-specific, interaction at phase borders. Additional indications for a weak electromagnetic interaction exist. Furthermore, the experimental results reveal that some types of quanta of the new form of 'field-like' matter exhibit positive mass, as normal matter, but others exhibit a negative mass content, both in the order of magnitude of the Planck mass. Memory effects in normal matter were detected after absorption of quanta of the new form of soft matter. In general, the findings characterize the quanta of 'fieldlike' matter as WIMP candidates of a cosmic background radiation of cold dark matter (quanta with positive mass) as well as of a cosmic background radiation of dark energy (quanta with negative mass). During visible sun eclipses in 1989, 1996 and. 1999, as well as during full moon of 6 January 2001, a so-far unknown form of dark-matter-radiation ('dark radiation') was detected. The quanta of this 'dark radiation' travel with the speed of light, but reveal macroscopic real mass, with positive and with negative mass content. The

  6. Bayesian-statistical decision threshold, detection limit, and confidence interval in nuclear radiation measurement

    International Nuclear Information System (INIS)

    Weise, K.

    1998-01-01

    When a contribution of a particular nuclear radiation is to be detected, for instance, a spectral line of interest for some purpose of radiation protection, and quantities and their uncertainties must be taken into account which, such as influence quantities, cannot be determined by repeated measurements or by counting nuclear radiation events, then conventional statistics of event frequencies is not sufficient for defining the decision threshold, the detection limit, and the limits of a confidence interval. These characteristic limits are therefore redefined on the basis of Bayesian statistics for a wider applicability and in such a way that the usual practice remains as far as possible unaffected. The principle of maximum entropy is applied to establish probability distributions from available information. Quantiles of these distributions are used for defining the characteristic limits. But such a distribution must not be interpreted as a distribution of event frequencies such as the Poisson distribution. It rather expresses the actual state of incomplete knowledge of a physical quantity. The different definitions and interpretations and their quantitative consequences are presented and discussed with two examples. The new approach provides a theoretical basis for the DIN 25482-10 standard presently in preparation for general applications of the characteristic limits. (orig.) [de

  7. A new mechanism of ionizing radiation detection for positron emission tomography: modulation of optical properties

    Science.gov (United States)

    Tao, Li; Daghighian, Henry M.; Levin, Craig S.

    2016-10-01

    Using conventional scintillation detection, the fundamental limit in positron emission tomography (PET) annihilation photon pair coincidence time resolution is strongly dependent on the inherent temporal variances generated during the scintillation process, yielding an intrinsic physical limit of around 100 ps. On the other hand, modulation mechanisms of a material's optical properties as exploited in the optical telecommunications industry can be orders of magnitude faster. In this paper we borrow from the concept of optics pump-probe measurement to study whether ionizing radiation can also produce fast modulations of optical properties, which can be utilized as a novel method for radiation detection. We show that a refractive index modulation of approximately 5x10-6 is induced by interactions in a cadmium telluride (CdTe) crystal from a 511 keV photon source. Furthermore, using additional radionuclide sources, we show that the amplitude of the optical modulation signal varies linearly with both the radiation source flux rate and average photon energy.

  8. How Can Synchrotron Radiation Techniques Be Applied for Detecting Microstructures in Amorphous Alloys?

    Directory of Open Access Journals (Sweden)

    Gu-Qing Guo

    2015-11-01

    Full Text Available In this work, how synchrotron radiation techniques can be applied for detecting the microstructure in metallic glass (MG is studied. The unit cells are the basic structural units in crystals, though it has been suggested that the co-existence of various clusters may be the universal structural feature in MG. Therefore, it is a challenge to detect microstructures of MG even at the short-range scale by directly using synchrotron radiation techniques, such as X-ray diffraction and X-ray absorption methods. Here, a feasible scheme is developed where some state-of-the-art synchrotron radiation-based experiments can be combined with simulations to investigate the microstructure in MG. By studying a typical MG composition (Zr70Pd30, it is found that various clusters do co-exist in its microstructure, and icosahedral-like clusters are the popular structural units. This is the structural origin where there is precipitation of an icosahedral quasicrystalline phase prior to phase transformation from glass to crystal when heating Zr70Pd30 MG.

  9. Sensor and method for measurment of select components of a material based on detection of radiation after interaction with the material

    International Nuclear Information System (INIS)

    Chase, L.M.; Anderson, L.M.; Norton, M.K.

    1993-01-01

    A sensor is described for measuring one or more select components of a sheet, comprising: a radiation source for emitting radiation toward the sheet; a plurality of detecting means, wherein at least one detecting means is offset from the source, for detecting radiation after interaction with the sheet; means for directing the radiation so that the radiation makes multiple interactions with the sheet in moving from the source to the detecting means, wherein the directing means includes a first reflector and second reflector defining a sheet space for the sheet to occupy; means for computing a ratio of the intensity of the detected radiation when the sheet is absent from the sheet space and the intensity of the detected radiation when the sheet occupies the sheet space; and means for computing the absorption power of the sheet from the intensity of the detected radiation

  10. Detection of the Level of Reactive Oxygen Species Induced by Ionizing Radiation in Cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Kyu; Chung, Dong Min; Kim, Jin-Hong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    By definition, the direct effect is referred to interaction between photon and DNA molecule, whereas the indirect effect is mediated by the reactive oxygen species (ROS) generated by radiolysis and subsequent reaction. It has been reported that ROS produced after exposure to IR can react with cellular materials such as DNA, proteins, carbohydrates and lipids. ROS is free radicals such as the superoxide anion, hydroxyl radicals and the non-radical hydrogen peroxide. Cells generate ROS during aerobic metabolism. Excessive production of ROS can lead to oxidative stress, genetic alteration and even cell death. It has been reported that ROS plays a critical role in radiation-induced cell injury. Thus, it is of great interest to determine the radiation-induced ROS level. Many kinds of methods to detect the level of ROS have been developed so far. There were random changes of fluorescence intensity in the treatment after irradiation. This result meant that this protocol was not appropriate for determination of radiation-induced ROS. On the other hand, the fluorescence intensity was increased in a dose-dependent manner when the cells were treated with the DCFH-DA solution before irradiation. Conclusions can be drawn from the experimental results of this study. In order to properly measure the ROS level in the cells exposed to ionizing radiation, the cells should be treated with the DCFH-DA solution before irradiation.

  11. Ultrasound-Detected Thyroid Nodule Prevalence and Radiation Dose from Fallout

    Science.gov (United States)

    Land, C. E.; Zhumadilov, Z.; Gusev, B. I.; Hartshorne, M. H.; Wiest, P. W.; Woodward, P. W.; Crooks, L. A.; Luckyanov, N. K.; Fillmore, C. M.; Carr, Z.; Abisheva, G.; Beck, H. L.; Bouville, A.; Langer, J.; Weinstock, R.; Gordeev, K. I.; Shinkarev, S.; Simon, S. L.

    2014-01-01

    Settlements near the Semipalatinsk Test Site (SNTS) in northeastern Kazakhstan were exposed to radioactive fallout during 1949–1962. Thyroid disease prevalence among 2994 residents of eight villages was ascertained by ultrasound screening. Malignancy was determined by cytopathology. Individual thyroid doses from external and internal radiation sources were reconstructed from fallout deposition patterns, residential histories and diet, including childhood milk consumption. Point estimates of individual external and internal dose averaged 0.04 Gy (range 0–0.65) and 0.31 Gy (0–9.6), respectively, with a Pearson correlation coefficient of 0.46. Ultrasound-detected thyroid nodule prevalence was 18% and 39% among males and females, respectively. It was significantly and independently associated with both external and internal dose, the main study finding. The estimated relative biological effectiveness of internal compared to external radiation dose was 0.33, with 95% confidence bounds of 0.09–3.11. Prevalence of papillary cancer was 0.9% and was not significantly associated with radiation dose. In terms of excess relative risk per unit dose, our dose–response findings for nodule prevalence are comparable to those from populations exposed to medical X rays and to acute radiation from the Hiroshima and Nagasaki atomic bombings. PMID:18363427

  12. [Effects of electromagnetic radiation on health and immune function of operators].

    Science.gov (United States)

    Li, Yan-zhong; Chen, Shao-hua; Zhao, Ke-fu; Gui, Yun; Fang, Si-xin; Xu, Ying; Ma, Zi-jian

    2013-08-01

    To investigate the effects of electromagnetic radiation on the physiological indices and immune function of operators. The general conditions and electromagnetic radiation awareness rate of 205 operators under electromagnetic radiation were evaluated using a self-designed questionnaire. Physical examination, electrocardiography, and routine urine test were performed in these operators. Peripheral blood was collected from the operators under electromagnetic radiation for blood cell counting and biochemical testing, and their peripheral blood lymphocytes were cultured for determination of chromosomal aberrant frequency and micronucleus frequency. The data from these operators (exposure group) were compared with those of 95 ordinary individuals (control group). The chief complaint of giddiness, tiredness, dizziness, and amnesia showed significant differences between the exposure group and control group (P electromagnetic radiation damage was significantly higher in the exposure group than in the control group. The difference in bradycardia was significant between the two groups (P Electromagnetic radiation may lead to the changes in physiological indices, genetic effects, and immune function and affect the health and immune function in operators. The adverse effects are increased as the working years increase. So it is important to strengthen occupational protection of operators under electromagnetic radiation.

  13. The effects of radiofrequency electromagnetic radiation on sperm function.

    Science.gov (United States)

    Houston, B J; Nixon, B; King, B V; De Iuliis, G N; Aitken, R J

    2016-12-01

    Mobile phone usage has become an integral part of our lives. However, the effects of the radiofrequency electromagnetic radiation (RF-EMR) emitted by these devices on biological systems and specifically the reproductive systems are currently under active debate. A fundamental hindrance to the current debate is that there is no clear mechanism of how such non-ionising radiation influences biological systems. Therefore, we explored the documented impacts of RF-EMR on the male reproductive system and considered any common observations that could provide insights on a potential mechanism. Among a total of 27 studies investigating the effects of RF-EMR on the male reproductive system, negative consequences of exposure were reported in 21. Within these 21 studies, 11 of the 15 that investigated sperm motility reported significant declines, 7 of 7 that measured the production of reactive oxygen species (ROS) documented elevated levels and 4 of 5 studies that probed for DNA damage highlighted increased damage due to RF-EMR exposure. Associated with this, RF-EMR treatment reduced the antioxidant levels in 6 of 6 studies that discussed this phenomenon, whereas consequences of RF-EMR were successfully ameliorated with the supplementation of antioxidants in all 3 studies that carried out these experiments. In light of this, we envisage a two-step mechanism whereby RF-EMR is able to induce mitochondrial dysfunction leading to elevated ROS production. A continued focus on research, which aims to shed light on the biological effects of RF-EMR will allow us to test and assess this proposed mechanism in a variety of cell types. © 2016 Society for Reproduction and Fertility.

  14. Primary observation on adherent function of bone marrow stromal cells in mice post combined radiation-burn injury

    International Nuclear Information System (INIS)

    Chen Xinghua; Luo Chengji; Guo Chaohua; Wang Ping; Deng Xuecai

    1999-01-01

    Objective: To investigate the adherent function of bone marrow stromal cells in hematopoietic inductive microenvironment post combined radiation-burn injury. Methods: The expression of cell adhesion molecules including vascular cell adhesion molecule-1 (VCAM-1), fibro-connection (Fn), laminin (Ln) and collagen type IV (Col IV) on bone marrow stromal cells cultured in vitro was detected by flow cytometry and the binding capacity of bone marrow mononuclear cells to stromal cell adherence layer was tested by cell binding assay and cell binding blocking assay respectively from mice treated with 5.0 Gy γ-ray 15% of total body surface area (TBSA), third-degree burn injury and combined irradiation-burn injury, respectively. Results: 1. The expression levels of molecules mentioned above in burn-injured mice were the highest. The molecules levels in control mice were greater than those in radiation-injured mice, which were lower than those in mice with combined radiation-burn injury. 2. The binding capacity of stromal cell adherence layer in burn-injured mice was greater than that in control mice, and significantly increased from 3 to 7 days post injury as compared with that in controls, radiation-injured mice and combined radiation-burn-injured mice, respectively (P < 0.05-0.01). Contrarily, the capacity of binding in the radiation-injured and combined radiation-burn-injured mice was the lowest from 3 to 7 days post injury. 3. The binding rate of bone marrow mononuclear cells to stromal cell adherence layer descended in different degrees after pre-treatment with monoclonal antibodies directed to VCAM-1, Fn, Ln, or Col IV respectively or VCAM-1 combined with anti-Fn, anti-Ln or anti-Col IV, respectively, in stromal cell adherence layer. Conclusion: The damage of cell adherent function for bone marrow hematopoietic inductive microenvironment post combined radiation-burn injury might be one of the important factors in hematopoietic disorder in combined radiation-burn injury

  15. Yield of Prompt Gamma Radiation in Slow-Neutron Induced Fission of 235U as a Function of the Total Fragment Kinetic Energy

    Energy Technology Data Exchange (ETDEWEB)

    Albinsson, H [Chalmers Univ. of Technology, Goeteborg (SE)

    1971-07-01

    Fission gamma radiation yields as functions of the total fragment kinetic energy were obtained for 235U thermal-neutron induced fission. The fragments were detected with silicon surface-barrier detectors and the gamma radiation with a Nal(Tl) scintillator. In some of the measurements mass selection was used so that the gamma radiation could also be measured as a function of fragment mass. Time discrimination between the fission gammas and the prompt neutrons released in the fission process was employed to reduce the background. The gamma radiation emitted during different time intervals after the fission event was studied with the help of a collimator, the position of which was changed along the path of the fission fragments. Fission-neutron and gamma-ray data of previous experiments were used for comparisons of the yields, and estimates were made of the variation of the prompt gamma-ray energy with the total fragment kinetic energy

  16. Embedded Detection and Correction of SEU Bursts in SRAM Memories Used as Radiation Detectors

    CERN Document Server

    Secondo, R.; Danzeca, S.; Losito, R.; Peronnard, P.; Masi, A.; Brugger, M.; Dusseau, L.

    2016-01-01

    SRAM memories are widely used as particle fluence detectors in high radiation environments, such as in the Radiation Monitoring System (RadMon) currently in operation in the CERN accelerator complex. Multiple Cell Upsets (MCUs), arising from micro-latchup events, are characterized by a large number of SEUs, ultimately affecting the measurement of particle fluxes and resulting in corrupted data and accuracy losses. A study of the generation of this type of SEU bursts was performed on an 8 Mbit 90-nm SRAM memory. Experimental tests were carried out with a focused beam of protons on target as well as in a mixed field environment dominated by high energy hadrons. A solution approach using an on-line detection and correction algorithm embedded on an FPGA was investigated and evaluated for use on a RadMon device.

  17. Radiation Detection and Dual-Energy X-Ray Imaging for Port Security

    Energy Technology Data Exchange (ETDEWEB)

    Pashby, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Glenn, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Divin, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Martz, H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-08-09

    Millions of cargo containers are transported across the United States border annually and are inspected for illicit radioactive material and contraband using a combination of passive radiation portal monitors (RPM) and high energy X-ray non-intrusive inspection (NII) systems. As detection performance is expected to vary with the material composition of cargo, characterizing the types of material present in cargo is important to national security. This work analyzes the passive radiation and dual energy radiography signatures from on RPM and two NII system, respectively. First, the cargos were analyzed to determine their ability to attenuate emissions from an embedded radioactive source. Secondly, dual-energy X-ray discrimination was used to determine the material composition and density of the cargos.

  18. Microfabricated electrochemical sensor for the detection of radiation-induced DNA damage

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.; Rivas, G.; Ozsoz, M.; Grant, D.H.; Cai, X.; Parrado, C. [New Mexico State Univ., Las Cruces, NM (United States)

    1997-04-01

    An electrochemical biosensor protocol for the detection of radiation-induced DNA damage is described. The procedure employs a dsDNA-coated screen-printed electrode and relies on changes in the guanine-DNA oxidation signal upon exposure to ultraviolet radiation. The decreased signal is ascribed primarily to conformational changes in the DNA and to the photoconversion of the guanine-DNA moiety to a nonelectroactive monomeric base product. Factors influencing the response of these microfabricated DNA sensors, such as irradiation time, wavelength, and distance, are explored, and future prospects are discussed. Similar results are given for the use of bare strip electrodes in connection with irradiated DNA solutions. 8 refs., 4 figs.

  19. Radioprotective Effect of Lidocaine on Function and Ultrastructure of Salivary Glands Receiving Fractionated Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hakim, Samer George, E-mail: samer.hakim@mkg-chir.mu-luebeck.de [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Benedek, Geza Attila [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Su Yuxiong [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Department of Oral and Maxillofacial Surgery, Sun Yat-Sen University, Guanghua School of Stomatology, Guanghua (China); Jacobsen, Hans Christian [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Klinger, Matthias [Institute of Anatomy, University of Luebeck, Luebeck (Germany); Dendorfer, Andreas [Institute of Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck (Germany); Hemmelmann, Claudia [Institute of Medical Biometry and Statistics, University of Luebeck, Luebeck (Germany); Meller, Birgit [Department of Radiology and Nuclear Medicine, University of Luebeck, Luebeck (Germany); Nadrowitz, Roger; Rades, Dirk [Department of Radiation Oncology, University of Luebeck, Luebeck (Germany); Sieg, Peter [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany)

    2012-03-15

    Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.

  20. Radioprotective Effect of Lidocaine on Function and Ultrastructure of Salivary Glands Receiving Fractionated Radiation

    International Nuclear Information System (INIS)

    Hakim, Samer George; Benedek, Gèza Attila; Su Yuxiong; Jacobsen, Hans Christian; Klinger, Matthias; Dendorfer, Andreas; Hemmelmann, Claudia; Meller, Birgit; Nadrowitz, Roger; Rades, Dirk; Sieg, Peter

    2012-01-01

    Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.

  1. Satellite orbits perturbed by direct solar radiation pressure: general expansion of the disturbing function

    International Nuclear Information System (INIS)

    Hughes, S.

    1977-01-01

    An expression is derived for the solar radiation pressure disturbing function on an Earth satellite orbit which takes into account the variation of the solar radiation flux with distance from the Sun's centre and the absorption of radiation by the satellite. This expression is then expanded in terms of the Keplerian elements of the satellite and solar orbits using Kaula's method (Astr. J.; 67:300 (1962)). The Kaula inclination functions are replaced by an equivalent set of modified Allan (Proc. R. Soc. A.; 288:60 (1965)) inclination functions. The resulting expression reduces to the form commonly used in solar radiation pressure perturbation studies (e.g. Aksnes, Cel. Mech.; 13:89 (1976)), when certain terms are neglected. If, as happens quite often in practice, a satellite's orbit is in near-resonance with certain of these neglected terms, these near-resonant terms can cause changes in the satellite's orbital elements comparable to those produced by the largest term in Aksnes's expression. A new expression for the solar radiation pressure disturbing function expansion is suggested for use in future studies of satellite orbits perturbed by solar radiation pressure. (author)

  2. Measuring element for detection and dose measurement of gamma radiation and neutrons and manufacturing method for the measuring element

    International Nuclear Information System (INIS)

    Piesch, E.; John, W.

    1979-01-01

    The measuring element consists of a bubble-free glass composed on the basis of metaphosphate material. The detection of the γ-radiation takes place through the photoluminescence of the element, and detection of the neutrons by means of resulting β particles producing Cerenkov radiation in the radioluminescence material, that can be measured. For this purpose in addition to Ag the glass contains As as a second excitable element. (DG) [de

  3. "Detecting Differential Item Functioning and Differential Step Functioning due to Differences that ""Should"" Matter"

    Directory of Open Access Journals (Sweden)

    Tess Miller

    2010-07-01

    Full Text Available This study illustrates the use of differential item functioning (DIF and differential step functioning (DSF analyses to detect differences in item difficulty that are related to experiences of examinees, such as their teachers' instructional practices, that are relevant to the knowledge, skill, or ability the test is intended to measure. This analysis is in contrast to the typical use of DIF or DSF to detect differences related to characteristics of examinees, such as gender, language, or cultural knowledge, that should be irrelevant. Using data from two forms of Ontario's Grade 9 Assessment of Mathematics, analyses were performed comparing groups of students defined by their teachers' instructional practices. All constructed-response items were tested for DIF using the Mantel Chi-Square, standardized Liu Agresti cumulative common log-odds ratio, and standardized Cox's noncentrality parameter. Items exhibiting moderate to large DIF were subsequently tested for DSF. In contrast to typical DIF or DSF analyses, which inform item development, these analyses have the potential to inform instructional practice.

  4. A Fusion of Multiagent Functionalities for Effective Intrusion Detection System

    OpenAIRE

    Dhanalakshmi Krishnan Sadhasivan; Kannapiran Balasubramanian

    2017-01-01

    Provision of high security is one of the active research areas in the network applications. The failure in the centralized system based on the attacks provides less protection. Besides, the lack of update of new attacks arrival leads to the minimum accuracy of detection. The major focus of this paper is to improve the detection performance through the adaptive update of attacking information to the database. We propose an Adaptive Rule-Based Multiagent Intrusion Detection System (ARMA-IDS) to...

  5. Sensitivity of radiation monitoring systems in Manila Ports in detecting contamination in foodstuff shipments

    International Nuclear Information System (INIS)

    Romallosa, Kristine Marie D.; Caseria, Estrella S.; Piquero, Ronald E.; Agustin, Jan Aldrich A.

    2011-01-01

    During the Fukushima Nuclear Power Plant accident in Japan, one of the Philippines' measures to protect the public from radiological hazards of the accident is by monitoring agricultural and food imports for radioactive contamination. In this study, the sensitivity of the mobile Radiation Monitoring System (RM) in Manila Ports in detecting contamination in incoming foodstuff shipments was determined. Large volume synthetic 137 Cs reference sources were used to determine the minimum detectable concentration (MDC) of the RMS. The reference sources have radioactivity concentrations that are comparable to the PNRI guidance level of 1000 Bg/kg for 137 Cs that is destined for general consumption. Results of the MDC measurements show that the RMS units are sensitive enough to detect radioactivity levels that are within the guidance levels provided that a) the minimum package lot is approximately 200 kg, b) the package is positioned at the detector side, and c) the alarm setting of RMS is as calibrated. It was therefore established that the RMS can be used to initially screen incoming foodstuff shipments of possible contamination and thereby help minimize potential radiation exposures to the public. (author)

  6. The signature-based radiation-scanning approach to standoff detection of improvised explosive devices

    International Nuclear Information System (INIS)

    Brewer, R.L.; Dunn, W.L.; Heider, S.; Matthew, C.; Yang, X.

    2012-01-01

    The signature-based radiation-scanning technique for detection of improvised explosive devices is described. The technique seeks to detect nitrogen-rich chemical explosives present in a target. The technology compares a set of “signatures” obtained from a test target to a collection of “templates”, sets of signatures for a target that contain an explosive in a specific configuration. Interrogation of nitrogen-rich fertilizer samples, which serve as surrogates for explosives, is shown experimentally to be able to discriminate samples of 3.8 L and larger. - Highlights: ► Signature-based radiation-scanning techniques applied to detection of explosives. ► Nitrogen-rich fertilizer samples served as surrogate explosive samples. ► Signatures of a target compared to collections of templates of surrogate explosives. ► Figure-of-merit determined for neutron and neutron-induced gamma-ray signatures. ► Discrimination of surrogate explosive from inert samples of 3.8 L and larger.

  7. Leukocyte-reduction filters and radiation do not cause significant changes in platelet function

    International Nuclear Information System (INIS)

    Nagura, Yutaka; Tsuno, Hirokazu; Shibata, Yoichi; Takahashi, Koki

    2003-01-01

    In the present study, we investigated the effects of radiation and leukocyte-reduction filters on platelet function. Platelet aggregation in response to collagen and ADP were measured prior to and after irradiation and filtration, as were the platelet recovery rate and complement factor C3. Four types of leukocyte-reduction filter were used, namely positively-, negatively-, and non-charged filters (all of polyester composition), as well as a polyurethane filter. Radiation itself did not significantly affect either the platelet recovery rate, platelet function, or C3 value. On the other hand, filtration through polyester leukocyte-reduction filters resulted in a significant reduction in the platelet recovery rate, an effect not observed with the polyurethane filter. However, none of the filters caused significant changes in platelet function or in C3 value. We concluded that radiation and filtration do not cause significant changes in platelet function, but polyurethane filters are superior to polyester filters in relation to platelet recovery. (author)

  8. Vector Green's function algorithm for radiative transfer in plane-parallel atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Qin Yi [School of Physics, University of New South Wales (Australia)]. E-mail: yi.qin@csiro.au; Box, Michael A. [School of Physics, University of New South Wales (Australia)

    2006-01-15

    Green's function is a widely used approach for boundary value problems. In problems related to radiative transfer, Green's function has been found to be useful in land, ocean and atmosphere remote sensing. It is also a key element in higher order perturbation theory. This paper presents an explicit expression of the Green's function, in terms of the source and radiation field variables, for a plane-parallel atmosphere with either vacuum boundaries or a reflecting (BRDF) surface. Full polarization state is considered but the algorithm has been developed in such way that it can be easily reduced to solve scalar radiative transfer problems, which makes it possible to implement a single set of code for computing both the scalar and the vector Green's function.

  9. Vector Green's function algorithm for radiative transfer in plane-parallel atmosphere

    International Nuclear Information System (INIS)

    Qin Yi; Box, Michael A.

    2006-01-01

    Green's function is a widely used approach for boundary value problems. In problems related to radiative transfer, Green's function has been found to be useful in land, ocean and atmosphere remote sensing. It is also a key element in higher order perturbation theory. This paper presents an explicit expression of the Green's function, in terms of the source and radiation field variables, for a plane-parallel atmosphere with either vacuum boundaries or a reflecting (BRDF) surface. Full polarization state is considered but the algorithm has been developed in such way that it can be easily reduced to solve scalar radiative transfer problems, which makes it possible to implement a single set of code for computing both the scalar and the vector Green's function

  10. Radiation effects on regeneration and T-cell-inducing function of the thymus

    International Nuclear Information System (INIS)

    Hirokawa, K.; Sado, T.

    1984-01-01

    Radiation effects on regeneration and T-cell-inducing function of the thymus were studied in three sets of experiments. When TXB mice were grafted with 1-week-old thymus which had been previously irradiated at various doses, an exponential decrease was observed in the morphological regeneration of the thymus grafts and in their T-cell-inducing function at doses of 600 R and over, showing about 10% that of the control at 1500 R. When in situ thymus of adult mice was locally irradiated, the radiation effect on T-cell-inducing function was less pronounced as compared with the first experiment; i.e., about 40% of the control at 1797 R. When in situ thymus of 1-day-old newborn mice was locally irradiated, regeneration potential of 1-day-old newborn thymus was highly resistant to radiation exposure and no effect on immunological functions was observed even by local irradiation of 2000 R

  11. Multi-channel Waveform Sampling ASIC for radiation detection and measurement

    International Nuclear Information System (INIS)

    Shimazoe, K.; Takahashi, H.; Yeom, J.Y.; Furumiya, T.; Ohi, J.

    2013-01-01

    We have designed and fabricated a 16-channel Waveform Sampling ASIC for radiation detection and measurement. Waveform sampling is very important for the pulse shape analysis and discrimination, which is often used in radiation detection to discriminate different radiations such as alpha, beta and gamma rays. One channel of the fabricated ASIC consists of a charge-sensitive preamplifier, a VGA (Variable Gain Amplifier), an ADC (Analog to Digital Converter) and digital circuits. The preamplifier converts the current signal to the voltage signal, and the VGA amplifies the signal to appropriate level for the ADC. The ADC was designed to digitize the waveform with a frequency of 100 MHz and a resolution of 6bits. Digital circuits consist of a free-running ADC and a multiplexer which were designed to convert a digitized 100 MHz/6bit signal to a 200 MHz/3bit one, which is effective for the reduction of the number and for the achievement of the high integration in one chip. This chip was designed and fabricated with 0.35 μm CMOS technology by ROHM and the size of the ASIC is 4.9 mm by 4.9 mm. The design concept and some experimental results are shown in this paper. -- Highlights: ► Waveform sampling (WS) ASIC is newly developed for pulse shape discrimination. ► WS ASIC can be used for radiation measurement and discrimination. ► WS ASIC is fabricated by submicron CMOS technology for 5 mm × 5 mm area. ► WS ASIC achieves high integration and can be used in very limited space

  12. Infuence of gamma radiation on the rheological and functional properties of bread wheats

    International Nuclear Information System (INIS)

    Paredes-Lopez, O.; Covarrubias-Alvarez, M.M.

    1984-01-01

    The effects of gamma irradiation on some biochemical, rheological and functional properties of bread wheats were studied. Two wheat cultivars were selected to represent medium-strong and weak dough mixing strengths. Falling number values were severely depressed at doses of 500 and 1000 krad. Rheological dough properties, as assessed with the mixograph and farinograph, were also investigated. Radiation at medium doses produced an increase in the farinograph water absorption for both wheats. Radiation decreased the amount of bound water as compared to the control sample. For the medium-strong wheat low levels of radiation produced bread with volumes and overall bread quality equal to or slightly better than those of the control flour, whereas for the weak wheat an improvement of the baking performance was obtained at all the low doses of radiation. However, the overall bread quality of both wheats was highly reduced at medium doses of radiation. (author)

  13. Detection of mitochondrial DNA deletions in human cells induced by ionizing radiation

    International Nuclear Information System (INIS)

    Liu, Qing-Jie; Feng, Jiang-Bin; Lu, Xue; Li, Yu-Wen; Chen, De-Qing

    2008-01-01

    Full text: Purpose: To screen the novel mitochondrial DNA (mt DNA) deletions induced by ionizing radiation, and analyze the several kinds of mt DNA deletions, known as 3895 bp, 889 bp, 7436 bp or 4934 bp deletions. Methods: Long-range PCR with two pairs of primers, which could amplify the whole human mitochondrial genome, was used to analyze the lymphoblastoid cell line before and after exposed to 10 Gy 60 Co γ-rays. The limited condition PCR was used to certify the possible mt DNA deletion showed by long-range PCR. The PCR products were purified, cloned, sequenced and the sequence result were BLASTed. Regular PCR or nest-PCR were used to analyze the 3895 bp, 889 bp, 7436 bp or 4934 bp deletions before and after radiation exposure. The final PCR products were purified, sequenced and BALSTed on standard human mitochondrial genome sequence database. Results: (1) The predicted bands of mt DNA were observed on the control cell lines, and the possible mt DNA deletions were also detected on the irradiated cell lines. The deletions were certified by the limited condition PCR. The sequence BLAST results of the cloned PCR products showed that two kinds of deletions, 7455 bp deletion (nt 475-7929 in heavy strand) and 9225 bp deletion (nt 7714-369 in heavy strand), which were between two 8 bp direct repeats. Further bioinformatics analysis showed that the two deletions were novel deletions. (2) The 889 bp and 3895 bp deletion were not detected for the cell line samples not exposed to 60 Co γ-rays. The 889 bp and 3895 bp deletions were detected on samples exposed to 10 Gy 60 Co γ-rays. The BALST results showed that the 889 bp and 3895 deletions flanked nt 11688 bp-12576, nt 548 bp-4443, respectively. The 7436 bp deletion levels were not changed much before and after irradiation. (3) The 4934 bp deletions had the same pattern as 7436 bp deletion, but it could induced by radiation. Conclusions: Ionizing radiation could induce the human lymphoblastoid two novel mt DNA

  14. Effect of radiation dose level on the detectability of pulmonary nodules in chest tomosynthesis.

    Science.gov (United States)

    Asplund, Sara A; Johnsson, Åse A; Vikgren, Jenny; Svalkvist, Angelica; Flinck, Agneta; Boijsen, Marianne; Fisichella, Valeria A; Månsson, Lars Gunnar; Båth, Magnus

    2014-07-01

    To investigate the detectability of pulmonary nodules in chest tomosynthesis at reduced radiation dose levels. Eighty-six patients were included in the study and were examined with tomosynthesis and computed tomography (CT). Artificial noise was added to simulate that the tomosynthesis images were acquired at dose levels corresponding to 12, 32, and 70% of the default setting effective dose (0.12 mSv). Three observers (with >20, >20 and three years of experience) read the tomosynthesis cases for presence of nodules in a free-response receiver operating characteristics (FROC) study. CT served as reference. Differences between dose levels were calculated using the jack-knife alternative FROC (JAFROC) figure of merit (FOM). The JAFROC FOM was 0.45, 0.54, 0.55, and 0.54 for the 12, 32, 70, and 100% dose levels, respectively. The differences in FOM between the 12% dose level and the 32, 70, and 100% dose levels were 0.087 (p = 0.006), 0.099 (p = 0.003), and 0.093 (p = 0.004), respectively. Between higher dose levels, no significant differences were found. A substantial reduction from the default setting dose in chest tomosynthesis may be possible. In the present study, no statistically significant difference in detectability of pulmonary nodules was found when reducing the radiation dose to 32%. • A substantial radiation dose reduction in chest tomosynthesis may be possible. • Pulmonary nodule detectability remained unchanged at 32% of the effective dose. • Tomosynthesis might be performed at the dose of a lateral chest radiograph.

  15. Dendrimer functionalized radiation grafted hydrogels for tissue engineering applications

    International Nuclear Information System (INIS)

    Higa, Olga Z.; Sakuno, Lilian M.; Queiroz, Alvaro A.A. de

    2009-01-01

    Low density polyethylene (LDPE) films were modified by γ-ray radiation grafting of 2- hydroxyethylmethacrylate (HEMA). The covalent immobilization of polyglycerol dendrimer (PGLD) on LDPEG- HEMA surface was performed by using dicyclohexyl carbodiimide (DCC)/N,N-dimethylaminopyridine (DMAP) method. The occurrence of grafting polymerization of HEMA and further immobilization of PGLD was quantitatively confirmed by photoelectron spectroscopy (XPS) and fluorescence, respectively. The LDPEG- HEMA surface topography after PGLD coupling was studied by atomic force microscopy (AFM). The hydrophilicity of the LDPE-G-HEMA film was remarkably improved compared to that of the ungrafted LDPE. The core level XPS ESCA spectrum of HEMA-grafted LDPE showed two strong peaks at ∼286.6 eV (from hydroxyl groups and ester groups) and ∼289.1 eV (from ester groups) due to HEMA brushes grafted onto LDPE surfaces. The results from the cell adhesion studies shows that MCT3-E1 cells tended to spread more slowly on LDPE-G-HEMA than on LDPE-G-HEMA-i-PGLD. (author)

  16. A catheter-based radiation detector for endovascular detection of atheromatous plaques

    International Nuclear Information System (INIS)

    Mukai, Takahiro; Konishi, Junji; Nohara, Ryuji; Ogawa, Mikako; Ishino, Seigo; Saji, Hideo; Kambara, Naoshige; Kataoka, Kazuaki; Kanoi, Toru; Saito, Kazuhiro; Motomura, Hiroshi

    2004-01-01

    Although various radiopharmaceuticals have been developed for the detection of atheromas, external imaging techniques have limitations when it comes to the detection of small plaques. In this study, we developed a charged particle-sensitive detector for the endovascular detection of small plaques. The device consists of a probe, an automatic pullback unit and a controller. The probe, which consists of a plastic scintillator and flexible optical fibres, is 1.0 mm in diameter. The probe was inserted into a catheter placed on 18 F point sources, and then the radioactivity was measured as the probe was pulled out stepwise. The sensitivity for 18 F was 9.3 cps/kBq, and there was a close linear correlation between the peak counts and source dose until at least 0.8 MBq. Furthermore, this device showed low background counts ( 18 F point sources were set on the ball's surface. Even though 298 MBq of 18 F-fluorodeoxyglucose was injected into the ball, the point sources located every 10 mm on the ball's surface were detectable separately. The data gathered suggest that a catheter-based radiation detector in combination with charged particle-emitting radiopharmaceuticals is useful for the endovascular detection of small lesions such as coronary plaques. (orig.)

  17. Radiation detection at very low temperature. DRTBT 1996 Aussois - Course collection

    International Nuclear Information System (INIS)

    Bouchiat, Helene; Chardin, Gabriel; Cribier, Michel; L'Hote, Denis; Lamarre, Jean-Michel; Broniatowski, Alexandre; Feautrier, Philippe; Benoit, A.; Chapellier, Maurice; Torre, Jean-Pierre

    1996-11-01

    This publication gathers several courses which propose or address: Examples of studies of fundamental noises, Electronics of bolometers for the measurement of a radiation power, Digital processing of a signal, Kapitza resistance - thermal resistance between two solids, Ionisation-heat bolometers, Space projects using bolometers at very low temperature, Application of bolometric detection to sub-millimetre astrophysics (the SPM photometer on PRONAOS), The neutrino which came in from the cold, Application of bolometers to the analysis by ion beams, Counting of photons in visible and near infrared light - applications in astronomy

  18. Influence of surface active agents on the detection of beta radiation

    International Nuclear Information System (INIS)

    Mesquita, T.B.; Ruegg, E.F.

    1984-01-01

    It has been studied the efficiency of beta irradiation detection by liquid scintillation counting using the pesticide 14 C-lindane as radiation source and scientillation cocktails containing Triton-X, Arkopal, Tinoventin, Extravon-200, Oswalmida, Bigral, ethanol and methanol. Excepting the last 5 products, which led to a phase formation in the mixture, all other compounds, that are easily available in the local market, proved to be good substitute products for the well known Triton-X, an expensive and restrict emulsifier used for liquid scintillation measurement of aqueous solutions. (Author) [pt

  19. Method of shaping of direction-characterization of sensitivity of ionizing radiation detection probe

    International Nuclear Information System (INIS)

    Czarnecki, J.; Jaszczuk, J.; Kruczyk, M.; Slapa, M.; Wroblewski, T.

    1986-01-01

    A method of shaping of direction-characterization of sensitivity of the ionizing radiation detection probe, especially equipped with small gamma detectors is described. Two detectors are placed coaxially in the bases of the cylindrical shield. One of them is uncovered in the highest degree and the second is not covered to a maximum. The signals from them are processed on the standarized sequences of electrical impulses (taking into account the heights and the widths of the amplitude). 2 figs., 1 tab. (A.S.)

  20. A fast high-voltage current-peak detection system for the ALICE transition radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Verclas, Robert [Physikalisches Institut, Ruprecht-Karls-Universitaet Heidelberg (Germany); Collaboration: ALICE-Collaboration

    2016-07-01

    During LHC operation in run 1, the gaseous detectors of ALICE occasionally experienced simultaneous trips in their high voltage which affected the majority of the high voltage channels. These trips are caused by large anode currents in the detector and are potentially related to LHC machine operations. We developed and installed a fast current-peak detection system for the ALICE Transition Radiation Detector. This system is based on FPGA technology and monitors 144 out 522 high voltage channels minimally invasively at a maximum readout rate of 2 MHz. It is an integral part of the LHC beam monitoring system. We report on the latest status.

  1. Detection by EPR method of radiation treatment in dried fruits containing crystalline sugar

    International Nuclear Information System (INIS)

    Lehner, K.; Stachowicz, W.

    2006-01-01

    The results of EPR (electron paramagnetic resonance) measurements are presented on the detection ability and stability of radiation induced sugar-born radicals in the samples of dried (dehydrated) fruits available in the market and related to doses of 0.5, 1 and 3 kGy, respectively. The experiments have been conducted during 12 months of storage. Measurements were done with an EPR - 10 MINI spectrometer in X band (frequency of microwaves 9.5 GHz), St. Petersburg Instruments Ltd. The aim of the work was to prove the reliability of acceptability of the method in routine control of irradiated food. (author)

  2. Detection of radiation deformation in crystalline polymers using the speckle photography technique

    International Nuclear Information System (INIS)

    El-Ghandoor, H.; Hashem, A.A.; Sharaf, F.

    1995-01-01

    In order to measure the resulting deformation due to gamma irradiation of polymers, a new optical technique, namely speckle-photography, was established and used. Thin films of tetrafluoroethene, with constant thickness were irradiated by different doses of gamma rays and the diffraction patterns of a laser beam passing through these films were recorded using the speckle photography technique. This technique has been applied to detect the radiation deformation in (Teflon) TFE, which is a crystalline polymer. A diffraction pattern due to the TFE thin layer is obtained and superimposed on the interference pattern displaying the speckle pattern pairs recorded on the same emulsion. (author)

  3. Electric field detection of coherent synchrotron radiation in a storage ring generated using laser bunch slicing

    International Nuclear Information System (INIS)

    Katayama, I.; Shimosato, H.; Bito, M.; Furusawa, K.; Adachi, M.; Zen, H.; Kimura, S.; Katoh, M.; Shimada, M.; Yamamoto, N.; Hosaka, M.; Ashida, M.

    2012-01-01

    The electric field of coherent synchrotron radiation (CSR) generated by laser bunch slicing in a storage ring has been detected by an electro-optic sampling method. The gate pulses for sampling are sent through a large-mode-area photonic-crystal fiber. The observed electric field profile of the CSR is in good agreement with the spectrum of the CSR observed using Fourier transform far-infrared spectrometry, indicating good phase stability in the CSR. The longitudinal density profiles of electrons modulated by laser pulses were evaluated from the electric field profile.

  4. Preparation of Dithizone Functionalized Polystyrene for Detecting Heavy Metal Ion

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hyeon Ho; Kim, Younghun [Kwangwoon University, Seoul (Korea, Republic of)

    2015-04-15

    Colorimetric sensors were usually used to detect specific metal ions using selective color change of solutions. While almost organic dye in colorimetric sensors detected single molecule, dithizone (DTZ) solution could be separately detected above 5 kinds of heavy metal ions by the change of clear color. Namely, DTZ could be used as multicolorimetric sensors. However, DTZ was generally used as aqueous type and paper/pellet-type DTZ was not reported yet. Therefore, in this work, polystyrene (PS) was prepared to composite with DTZ and then DTZ/PS pellet was obtained, which was used to selectively detect 10 kinds of heavy metal ions. When 10 ppm of Hg and Co ions was exposed in DTZ/PS pellets, clear color change was revealed. It is noted that DTZ/PS pellet could be used in detecting of heavy metal ion as dry type.

  5. Role of functional imaging in treatment plan optimization of stereotactic body radiation therapy for liver cancer.

    Science.gov (United States)

    De Bari, Berardino; Jumeau, Raphael; Deantonio, Letizia; Adib, Salim; Godin, Sarah; Zeverino, Michele; Moeckli, Raphael; Bourhis, Jean; Prior, John O; Ozsahin, Mahmut

    2016-10-13

    We report the first known instance of the clinical use of 99mTc-mebrofenin hepatobiliary scintigraphy (HBS) for the optimization of radiotherapy treatment planning and for the follow-up of acute toxicity in a patient undergoing stereotactic body radiation therapy for hepatocellular carcinoma. In our experience, HBS allowed the identification and the sparing of more functioning liver areas, thus potentially reducing the risk of radiation-induced liver toxicity.

  6. Effects of radiation therapy on neuropsychological functioning in patients with nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Lee, P.W.H.; Hung, B.K.M.; Woo, E.K.W.; Tai, P.T.H.; Choi, D.T.K.

    1989-01-01

    Sixteen patients who had a nasopharyngeal carcinoma (NPC) who were treated with radiation therapy were followed up after a median duration of 5.5 years and given a battery of neuropsychological tests. Results were compared with a comparable group of newly diagnosed NPC patients awaiting radiation therapy. The irradiated group was significantly poorer in overall IQ, non-verbal memory recall, and reported a substantially greater number of memory related complaints. These results contrast with the complacent general assumption that radiation therapy has a negligible effect on adult functioning. (author)

  7. Post-radiation analgesia at rats and function of endogenous opiates

    International Nuclear Information System (INIS)

    Slivkova, E.; Smajda, B.; Paulikova, E.; Lackova, M.

    2002-01-01

    In this work post-radiation analgesia at rats as well as the function of endogenous opiates were tested. Males of rats were irradiated all-body dose 6 Gy. Hot-plate test was used. Dose of 8 mg of naloxone per kg of animal blocked perception of ache. This dose blocked analgetic effect of ionising radiation. Activity of phagocyte activity and phagocyte index were enhanced at rats which obtained naloxone. Authors stated that opiate system play a significant role at analgesia induced by radiation at rats and can modify response of immunity system on the stress

  8. Minimalism in radiation synthesis of biomedical functional nanogels.

    Science.gov (United States)

    Dispenza, Clelia; Sabatino, Maria Antonietta; Grimaldi, Natascia; Bulone, Donatella; Bondì, Maria Luisa; Casaletto, Maria Pia; Rigogliuso, Salvatrice; Adamo, Giorgia; Ghersi, Giulio

    2012-06-11

    A scalable, single-step, synthetic approach for the manufacture of biocompatible, functionalized micro- and nanogels is presented. In particular, poly(N-vinyl pyrrolidone)-grafted-(aminopropyl)methacrylamide microgels and nanogels were generated through e-beam irradiation of PVP aqueous solutions in the presence of a primary amino-group-carrying monomer. Particles with different hydrodynamic diameters and surface charge densities were obtained at the variance of the irradiation conditions. Chemical structure was investigated by different spectroscopic techniques. Fluorescent variants were generated through fluorescein isothiocyanate attachment to the primary amino groups grafted to PVP, to both quantify the available functional groups for bioconjugation and follow nanogels localization in cell cultures. Finally, a model protein, bovine serum albumin, was conjugated to the nanogels to demonstrate the attachment of biologically relevant molecules for targeting purposes in drug delivery. The described approach provides a novel strategy to fabricate biohybrid nanogels with a very promising potential in nanomedicine.

  9. The effectiveness of pretreatment physics plan review for detecting errors in radiation therapy

    International Nuclear Information System (INIS)

    Gopan, Olga; Zeng, Jing; Novak, Avrey; Nyflot, Matthew; Ford, Eric

    2016-01-01

    Purpose: The pretreatment physics plan review is a standard tool for ensuring treatment quality. Studies have shown that the majority of errors in radiation oncology originate in treatment planning, which underscores the importance of the pretreatment physics plan review. This quality assurance measure is fundamentally important and central to the safety of patients and the quality of care that they receive. However, little is known about its effectiveness. The purpose of this study was to analyze reported incidents to quantify the effectiveness of the pretreatment physics plan review with the goal of improving it. Methods: This study analyzed 522 potentially severe or critical near-miss events within an institutional incident learning system collected over a three-year period. Of these 522 events, 356 originated at a workflow point that was prior to the pretreatment physics plan review. The remaining 166 events originated after the pretreatment physics plan review and were not considered in the study. The applicable 356 events were classified into one of the three categories: (1) events detected by the pretreatment physics plan review, (2) events not detected but “potentially detectable” by the physics review, and (3) events “not detectable” by the physics review. Potentially detectable events were further classified by which specific checks performed during the pretreatment physics plan review detected or could have detected the event. For these events, the associated specific check was also evaluated as to the possibility of automating that check given current data structures. For comparison, a similar analysis was carried out on 81 events from the international SAFRON radiation oncology incident learning system. Results: Of the 356 applicable events from the institutional database, 180/356 (51%) were detected or could have been detected by the pretreatment physics plan review. Of these events, 125 actually passed through the physics review; however

  10. The effectiveness of pretreatment physics plan review for detecting errors in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Gopan, Olga; Zeng, Jing; Novak, Avrey; Nyflot, Matthew; Ford, Eric, E-mail: eford@uw.edu [Department of Radiation Oncology, University of Washington Medical Center, 1959 NE Pacific Street, Box 356043, Seattle, Washington 98195 (United States)

    2016-09-15

    Purpose: The pretreatment physics plan review is a standard tool for ensuring treatment quality. Studies have shown that the majority of errors in radiation oncology originate in treatment planning, which underscores the importance of the pretreatment physics plan review. This quality assurance measure is fundamentally important and central to the safety of patients and the quality of care that they receive. However, little is known about its effectiveness. The purpose of this study was to analyze reported incidents to quantify the effectiveness of the pretreatment physics plan review with the goal of improving it. Methods: This study analyzed 522 potentially severe or critical near-miss events within an institutional incident learning system collected over a three-year period. Of these 522 events, 356 originated at a workflow point that was prior to the pretreatment physics plan review. The remaining 166 events originated after the pretreatment physics plan review and were not considered in the study. The applicable 356 events were classified into one of the three categories: (1) events detected by the pretreatment physics plan review, (2) events not detected but “potentially detectable” by the physics review, and (3) events “not detectable” by the physics review. Potentially detectable events were further classified by which specific checks performed during the pretreatment physics plan review detected or could have detected the event. For these events, the associated specific check was also evaluated as to the possibility of automating that check given current data structures. For comparison, a similar analysis was carried out on 81 events from the international SAFRON radiation oncology incident learning system. Results: Of the 356 applicable events from the institutional database, 180/356 (51%) were detected or could have been detected by the pretreatment physics plan review. Of these events, 125 actually passed through the physics review; however

  11. New functionality of chalcogenide glasses for radiation sensing of nuclear wastes

    International Nuclear Information System (INIS)

    Ailavajhala, M.S.; Gonzalez-Velo, Y.; Poweleit, C.D.; Barnaby, H.J.; Kozicki, M.N.; Butt, D.P.; Mitkova, M.

    2014-01-01

    Highlights: • Study of thin film chalcogenide glasses under gamma radiation and a proposed radiation sensor design. • Structural changes were observed at various radiation doses. • Formation of Ag 2 Se in Se depleted glasses with sufficient radiation dose. • In conventional semiconductor chip environment, the proposed sensor has a linear current vs. dose behavior up to 600 J/cm 2 . - Abstract: Data about gamma radiation induced effects in Ge 40 Se 60 chalcogenide thin films and radiation induced silver diffusion within these are presented. Blanket films and devices were created to study the structural changes, diffusion products, and device performance. Raman spectroscopy, X-ray diffraction, current vs. voltage (I–V) and impedance measurements expound the behavior of Ge 40 Se 60 glass and silver diffusion within this glass under radiation. Raman study shows that there is a decrease in the area ratio between edge shared and corner shared structural units revealing structural reorganization occurring in the glasses as a result of gamma radiation. X-ray diffraction studies revealed that with sufficiently radiation dose it is also possible to create Ag 2 Se in selenium-depleted systems. Oxidation of the Ge enriched chalcogenide backbone is confirmed through the electrical performance of the sensing elements based on these films. Combination of these structural and diffusion products influences the device performance. The I–V behavior is characterized by increase in current and then stabilization as a function of radiation dose. Additionally, device modeling is also presented using Silvaco software and analytical methods to shed light on the device behavior. This type of sensor design and material characterizations facilitate in improving the radiation sensing capabilities of silver containing chalcogenide glass thin films

  12. New functionality of chalcogenide glasses for radiation sensing of nuclear wastes

    Energy Technology Data Exchange (ETDEWEB)

    Ailavajhala, M.S., E-mail: m.ailavajhala@gmail.com [Department of Electrical and Computer Engineering, Boise State University, Boise, ID 83725 (United States); Gonzalez-Velo, Y. [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ 85287-5706 (United States); Poweleit, C.D. [Department of Physics, Arizona State University, Tempe, AZ 85287-5706 (United States); Barnaby, H.J.; Kozicki, M.N. [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ 85287-5706 (United States); Butt, D.P. [Department of Materials Science and Engineering, Boise State University, Boise, ID 83725 (United States); Mitkova, M., E-mail: maheshailavajhala@u.boisestate.edu [Department of Electrical and Computer Engineering, Boise State University, Boise, ID 83725 (United States)

    2014-03-01

    Highlights: • Study of thin film chalcogenide glasses under gamma radiation and a proposed radiation sensor design. • Structural changes were observed at various radiation doses. • Formation of Ag{sub 2}Se in Se depleted glasses with sufficient radiation dose. • In conventional semiconductor chip environment, the proposed sensor has a linear current vs. dose behavior up to 600 J/cm{sup 2}. - Abstract: Data about gamma radiation induced effects in Ge{sub 40}Se{sub 60} chalcogenide thin films and radiation induced silver diffusion within these are presented. Blanket films and devices were created to study the structural changes, diffusion products, and device performance. Raman spectroscopy, X-ray diffraction, current vs. voltage (I–V) and impedance measurements expound the behavior of Ge{sub 40}Se{sub 60} glass and silver diffusion within this glass under radiation. Raman study shows that there is a decrease in the area ratio between edge shared and corner shared structural units revealing structural reorganization occurring in the glasses as a result of gamma radiation. X-ray diffraction studies revealed that with sufficiently radiation dose it is also possible to create Ag{sub 2}Se in selenium-depleted systems. Oxidation of the Ge enriched chalcogenide backbone is confirmed through the electrical performance of the sensing elements based on these films. Combination of these structural and diffusion products influences the device performance. The I–V behavior is characterized by increase in current and then stabilization as a function of radiation dose. Additionally, device modeling is also presented using Silvaco software and analytical methods to shed light on the device behavior. This type of sensor design and material characterizations facilitate in improving the radiation sensing capabilities of silver containing chalcogenide glass thin films.

  13. Development of radiation-induced mutation techniques and functional genomics studies

    International Nuclear Information System (INIS)

    Kim, Dong Sub; Kang, Si Yong; Kim, Jin Baek

    2012-01-01

    This project has been performed to develop plant genetic resources using radiation (gamma-rays, ion-beam, space environments), to conduct functional genomics studies with mutant resources, and to develop new radiation plant breeding techniques using various radiation sources during 3 years. In the first section, we developed flower genetic resources, functional crop resources, and bio-industrial plant resources. In the second section, we cloned several mutated genes and studied mechanisms of gene expression and genetic diversity of mutations induced by gamma-rays. In the third section, we developed new plant breeding techniques using gamma-phytotron, heavy ion-beam, and space environments. Based on these results, a total of 8 cultivars containing Chrysanthemum, Hibiscus, kenaf, rice, and soybean were applied for plant variety protection (PVP) and a total of 4 cultivars were registered for PVP. Also, license agreement for the dwarf type Hibiscus mutant 'Ggoma' was conducted with Supro co. and the manufacturing technology for natural antioxidant pear-grape vinegar was transferred into Enzenic co. Also, 8 gene sequences, such as F3'H and LDOX genes associated with flower color in Chrysanthemum and EPSPS gene from Korean lawn grass, were registered in the database of National Center for Biotechnology Information (NCBI). In the future study, we will develop new radiation mutation breeding techniques through the mutation spectrum induced by various radiation sources, the studies for mechanism of the cellular response to radiation, and the comparative·structural·functional genomics studies for useful traits

  14. Effect of solar radiation on the functional components of mulberry (Morus alba L.) leaves.

    Science.gov (United States)

    Sugiyama, Mari; Katsube, Takuya; Koyama, Akio; Itamura, Hiroyuki

    2016-08-01

    The functional components of mulberry leaves have attracted the attention of the health food industry, and increasing their concentrations is an industry goal. This study investigated the effects of solar radiation, which may influence the production of flavonol and 1-deoxynojirimycin (DNJ) functional components in mulberry leaves, by comparing a greenhouse (poor solar radiation) and outdoor (rich solar radiation) setting. The level of flavonol in leaves cultivated in the greenhouse was markedly decreased when compared with those cultivated outdoors. In contrast, the DNJ content in greenhouse-cultivated plants was increased only slightly when compared with those cultivated outdoors. Interestingly, the flavonol content was markedly increased in the upper leaves of mulberry trees that were transferred from a greenhouse to the outdoors compared with those cultivated only in the outdoors. Solar radiation conditions influence the synthesis of flavonol and DNJ, the functional components of mulberry leaves. Under high solar radiation, the flavonol level becomes very high but the DNJ level becomes slightly lower, suggesting that the impact of solar radiation is great on flavonol but small on DNJ synthesis. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  15. A Fusion of Multiagent Functionalities for Effective Intrusion Detection System

    Directory of Open Access Journals (Sweden)

    Dhanalakshmi Krishnan Sadhasivan

    2017-01-01

    Full Text Available Provision of high security is one of the active research areas in the network applications. The failure in the centralized system based on the attacks provides less protection. Besides, the lack of update of new attacks arrival leads to the minimum accuracy of detection. The major focus of this paper is to improve the detection performance through the adaptive update of attacking information to the database. We propose an Adaptive Rule-Based Multiagent Intrusion Detection System (ARMA-IDS to detect the anomalies in the real-time datasets such as KDD and SCADA. Besides, the feedback loop provides the necessary update of attacks in the database that leads to the improvement in the detection accuracy. The combination of the rules and responsibilities for multiagents effectively detects the anomaly behavior, misuse of response, or relay reports of gas/water pipeline data in KDD and SCADA, respectively. The comparative analysis of the proposed ARMA-IDS with the various existing path mining methods, namely, random forest, JRip, a combination of AdaBoost/JRip, and common path mining on the SCADA dataset conveys that the effectiveness of the proposed ARMA-IDS in the real-time fault monitoring. Moreover, the proposed ARMA-IDS offers the higher detection rate in the SCADA and KDD cup 1999 datasets.

  16. Detection of helium atoms in irradiated metals using positron annihilation radiation

    International Nuclear Information System (INIS)

    Xu, Q.; Sato, K.; Yoshiie, T.; Ishizaki, T.; Nagata, S.

    2007-01-01

    Iron alloys are used widely in the nuclear industry. The production of He atoms induced by nuclear reaction increases with increasing neutron energy, and the interaction between He and defects becomes important in the fusion reactor. A new composition analysis method, coincidence Doppler broadening (CDB) of positron annihilation radiation, was employed to detect He atoms in ion irradiated Fe. The results of positron lifetime showed that the microvoids and voids were formed in ion irradiated Fe. The results of CDB measurement indicated that He atoms exited in the microvoids, and they exited in the microvoids even after annealing at 1223 K in ion irradiated Fe. CDB measurement, which is a nondestructive technique for testing materials, is an available method to detect He atoms. (authors)

  17. Design of Zigbee-Based Wireless Sensor suitable for Radiation Detection and Monitoring

    International Nuclear Information System (INIS)

    Madian, A.A.

    2012-01-01

    This paper presents a design for a wireless sensor nuclear radiation monitoring and detection based on Zigbee. The system consists of transmitter and receiver modules. The wireless sensor installed at transmitter whiles the receiver processing data. The communication between Tx and Rx done through Zigbee module using the protocol of CSMA/CA. The Zigbee has the advantages of reliable, power-efficient, and low-latency communications between low-cost Tx/Rx.The wireless sensor implementation can easily be deployed to discover unusual or abnormal radioactivity. The sensors are convenient to be installed indoors or outdoors, as well as to be mounted on mobile equipment's. All wireless nuclear detection sensors are designed using micro controller and other integrated systems

  18. Statistical analysis of DNT detection using chemically functionalized microcantilever arrays

    DEFF Research Database (Denmark)

    Bosco, Filippo; Bache, M.; Hwu, E.-T.

    2012-01-01

    The need for miniaturized and sensitive sensors for explosives detection is increasing in areas such as security and demining. Micrometer sized cantilevers are often used for label-free detection, and have previously been reported to be able to detect explosives. However, only a few measurements...... on the chemically treated surfaces results in significant bending of the cantilevers and in a decrease of their resonant frequencies. We present averaged measurements obtained from up to 72 cantilevers being simultaneously exposed to the same sample. Compared to integrated reference cantilevers with non...

  19. Detecting Lyme disease using antibody-functionalized carbon nanotubes

    Science.gov (United States)

    Dailey, Jennifer; Lerner, Mitchell; Goldsmith, Brett; Brisson, Dustin; Johnson, A. T. Charlie

    2011-03-01

    We combine antibodies for Lyme flagellar protein with carbon nanotube transistors to create an electronic sensor capable of definitive detection of Lyme disease. Over 35,000 cases of Lyme disease are reported in the United States each year, of which more than 23 percent are originally misdiagnosed. Rational design of the coupling of the biological system to the electronic system gives us a flexible sensor platform which we can apply to several biological systems. By coupling these antibodies to carbon nanotubes in particular, we allow for fast, sensitive, highly selective, electronic detection. Unlike antibody or biomarker detection, bacterial protein detection leads to positive identification of both early and late stage bacterial infections, and is easily expandable to environmental monitoring.

  20. Hybrid emergency radiation detection: a wireless sensor network application for consequence management of a radiological release

    Science.gov (United States)

    Kyker, Ronald D.; Berry, Nina; Stark, Doug; Nachtigal, Noel; Kershaw, Chris

    2004-08-01

    The Hybrid Emergency Radiation Detection (HERD) system is a rapidly deployable ad-hoc wireless sensor network for monitoring the radiation hazard associated with a radiation release. The system is designed for low power, small size, low cost, and rapid deployment in order to provide early notification and minimize exposure. The many design tradeoffs, decisions, and challenges in the implementation of this wireless sensor network design will be presented and compared to the commercial systems available. Our research in a scaleable modular architectural highlights the need and implementation of a system level approach that provides flexibility and adaptability for a variety of applications. This approach seeks to minimize power, provide mission specific specialization, and provide the capability to upgrade the system with the most recent technology advancements by encapsulation and modularity. The implementation of a low power, widely available Real Time Operating System (RTOS) for multitasking with an improvement in code maintenance, portability, and reuse will be presented. Finally future design enhancements technology trends affecting wireless sensor networks will be presented.

  1. Lower limits of detection in using carbon nanotubes as thermoluminescent dosimeters of beta radiation

    Science.gov (United States)

    Alanazi, Abdulaziz; Jurewicz, Izabela; Alalawi, Amani I.; Alyahyawi, Amjad; Alsubaie, Abdullah; Hinder, Steven; Bañuls-Ciscar, Jorge; Alkhorayef, Mohammed; Bradley, D. A.

    2017-11-01

    World-wide, on-going intensive research is being seen in adaptation of carbon nanotubes (CNTs) for a wide variety of applications, particular interest herein being in the thermoluminescent (TL) properties of CNTs and their sensitivity towards energetic radiations. Using beta radiation delivering dose levels of a few Gy it has been observed in previous study that strain and impurity defects in CNTs give rise to significant TL yields, providing an initial measure of the extent to which electron trapping centres exist in various qualities of CNT, from super-pure to raw. This in turn points to the possibility that there may be considerable advantage in using such media for radiation dosimetry applications, including for in vivo dosimetry. CNTs also have an effective atomic number similar to that of adipose tissue, making them suitable for soft tissue dosimetry. In present investigations various single-wall carbon nanotubes (SWCNT) samples in the form of buckypaper have been irradiated to doses in the range 35-1.3 Gy, use being made of a 90Sr beta source, the response of the CNTs buckypaper with dose showing a trend towards linearity. It is shown for present production methodology for buckypaper samples that the raw SWCNT buckypaper offer the greatest sensitivity, detecting doses down to some few tens of mGy.

  2. Detection of coherent X-ray transition radiation and its application to beam diagnostics

    International Nuclear Information System (INIS)

    Piestrup, M.A.; Boyers, D.G.; Pincus, C.I.; Li Qiang; Moran, M.J.; Bergstrom, J.C.; Caplan, H.S.; Silzer, R.M.; Skopik, D.M.; Rothbart, G.B.

    1989-01-01

    We investigate the use of coherent X-ray transition radiation to measure the energy of ultra-relativistic charged particles. This can be used for beam diagnostics for both high-repetition-rate and single-pulse, high-current accelerators. The research also has possible applications for the detection and identification of these particles. By selecting foil thickness and spacing, it is possible to design radiators whose angle of emission varies radically over a range of charged particle energies. We have constructed three coherent radiators and tested them at two accelerators using electron beam energies ranging from 50 to 228 MeV. Soft X-ray emission (1-3 keV) was emitted in a circularly symmetrical annulus with half-angle divergence of 2.5-9.0 mrad. The angle of peak emission was found to increase with electron-beam energy, in contrast to the incoherent case for which the angle of emission varies inversely with electron-beam energy. (orig.)

  3. Quality control of radiation counting systems and measurement of minimum detectable activity

    International Nuclear Information System (INIS)

    Song, Byoung Chul; Han, Sung Sim; Kim, Young Bok; Jee, Kwang Yong; Sohn, Se Chul

    2004-01-01

    Various radiation counters have been using to determine radioactivity of radwastes for disposal. A radiation counting system was set up using a radiation detector chosen in this study and its stability was investigated through the periodic determination of background and counting efficiencies in accordance with a quality control program to increase the confidence level. The average background level for the γ-spectrometer was 1.59 cps and the average counting level for the standard sample was 45248 dps within 20 confidence levels. The average alpha background level for the low background α/β counting system was 0.31 cpm and the efficiency for alpha counting was 34.38 %. The average beta background level for the α/β counting system was 1.30 cpm and the efficiency for beta counting was 46.5%. The background level in the region of 3H and 14C for the liquid scintillation counting system was 2.52 and 3.31 cpm and the efficiency for alpha counting was 58.5 and 95.6%, respectively. The minimum detectable activity for the γ-spectrometer was found to be 3.2 Bq/mL and 3.8 Bq/mL for the liquid scintillation counter, and 20.5 and 23.0 Bq/mL, respectively for the α and β counting system

  4. Neuropsychological function in adults after high dose fractionated radiation therapy of skull base tumors

    International Nuclear Information System (INIS)

    Glosser, Guila; McManus, Pat; Munzenrider, John; Austin-Seymour, Mary; Fullerton, Barbara; Adams, Judy; Urie, Marcia M.

    1997-01-01

    Purpose: To evaluate the long term effects of high dose fractionated radiation therapy on brain functioning prospectively in adults without primary brain tumors. Methods and Materials: Seventeen patients with histologically confirmed chordomas and low grade chondrosarcomas of the skull base were evaluated with neuropsychological measures of intelligence, language, memory, attention, motor function and mood following surgical resection/biopsy of the tumor prior to irradiation, and then at about 6 months, 2 years and 4 years following completion of treatment. None received chemotherapy. Results: In the patients without tumor recurrence or radiation necrosis, there were no indications of adverse effects on cognitive functioning in the post-acute through the late stages after brain irradiation. Even in patients who received doses of radiation up to 66 Cobalt Gy equivalent through nondiseased (temporal lobe) brain tissue, memory and cognitive functioning remained stable for up to 5 years after treatment. A mild decline in psycho-motor speed was seen in more than half of the patients, and motor slowing was related to higher radiation doses in midline and temporal lobe brain structures. Conclusion: Results suggest that in adults, tolerance for focused radiation is relatively high in cortical brain structures

  5. Fire Detection Tradeoffs as a Function of Vehicle Parameters

    Science.gov (United States)

    Urban, David L.; Dietrich, Daniel L.; Brooker, John E.; Meyer, Marit E.; Ruff, Gary A.

    2016-01-01

    Fire survivability depends on the detection of and response to a fire before it has produced an unacceptable environment in the vehicle. This detection time is the result of interplay between the fire burning and growth rates; the vehicle size; the detection system design; the transport time to the detector (controlled by the level of mixing in the vehicle); and the rate at which the life support system filters the atmosphere, potentially removing the detected species or particles. Given the large differences in critical vehicle parameters (volume, mixing rate and filtration rate) the detection approach that works for a large vehicle (e.g. the ISS) may not be the best choice for a smaller crew capsule. This paper examines the impact of vehicle size and environmental control and life support system parameters on the detectability of fires in comparison to the hazard they present. A lumped element model was developed that considers smoke, heat, and toxic product release rates in comparison to mixing and filtration rates in the vehicle. Recent work has quantified the production rate of smoke and several hazardous species from overheated spacecraft polymers. These results are used as the input data set in the lumped element model in combination with the transport behavior of major toxic products released by overheating spacecraft materials to evaluate the necessary alarm thresholds to enable appropriate response to the fire hazard.

  6. Smart phone based bacterial detection using bio functionalized fluorescent nanoparticles

    International Nuclear Information System (INIS)

    Rajendran, Vinoth Kumar; Bakthavathsalam, Padmavathy; Ali, Baquir Mohammed Jaffar

    2014-01-01

    We are describing immunochromatographic test strips with smart phone-based fluorescence readout. They are intended for use in the detection of the foodborne bacterial pathogens Salmonella spp. and Escherichia coli O157. Silica nanoparticles (SiNPs) were doped with FITC and Ru(bpy), conjugated to the respective antibodies, and then used in a conventional lateral flow immunoassay (LFIA). Fluorescence was recorded by inserting the nitrocellulose strip into a smart phone-based fluorimeter consisting of a light weight (40 g) optical module containing an LED light source, a fluorescence filter set and a lens attached to the integrated camera of the cell phone in order to acquire high-resolution fluorescence images. The images were analysed by exploiting the quick image processing application of the cell phone and enable the detection of pathogens within few minutes. This LFIA is capable of detecting pathogens in concentrations as low as 10 5 cfu mL −1 directly from test samples without pre-enrichment. The detection is one order of magnitude better compared to gold nanoparticle-based LFIAs under similar condition. The successful combination of fluorescent nanoparticle-based pathogen detection by LFIAs with a smart phone-based detection platform has resulted in a portable device with improved diagnosis features and having potential application in diagnostics and environmental monitoring. (author)

  7. Applications in Bioastronautics and Bioinformatics: Early Radiation Cataracts Detected by Noninvasive, Quantitative, and Remote Means

    Science.gov (United States)

    Ansari, Rafat R.; King, James F.; Giblin, Frank J.

    2000-01-01

    Human exploration of Mars is a key goal in NASA's exploration planning in the next 20 years. Maintaining crew health and good vision is certainly an important aspect of achieving a successful mission. Continuous radiation exposure is a risk factor for radiation-induced cataracts in astronauts because radiation exposure in space travel has the potential of accelerating the aging process (ref. 1). A patented compact device (ref. 2) based on the technique of dynamic light scattering (DLS) was designed for monitoring an astronaut's ocular health during long-duration space travel. This capability of early diagnosis, unmatched by any other clinical technique in use today, may enable prompt initiation of preventive/curative therapy. An Internet web-based system integrating photon correlation data and controlling the hardware to monitor cataract development in vivo at a remote site in real time (teleophthalmology) is currently being developed. The new technology detects cataracts very early (at the molecular level). Cataract studies onboard the International Space Station will be helpful in quantifying any adverse effect of radiation to ocular health. The normal lens in a human eye, situated behind the cornea, is a transparent tissue. It contains 35 wt % protein and 65 wt % water. Aging, disease (e.g., diabetes), smoking, dehydration, malnutrition, and exposure to ultraviolet light and ionizing radiation can cause agglomeration of the lens proteins. Protein aggregation can take place anywhere in the lens, causing lens opacity. The aggregation and opacification could produce nuclear (central portion of the lens) or cortical (peripheral) cataracts. Nuclear and posterior subcapsular (the membrane's capsule surrounds the whole lens) cataracts, being on the visual optical axis of the eye, cause visual impairment that can finally lead to blindness. The lens proteins, in their native state, are small in size. As a cataract develops, this size grows from a few nanometers

  8. Chemical vapor deposition diamond based multilayered radiation detector: Physical analysis of detection properties

    International Nuclear Information System (INIS)

    Almaviva, S.; Marinelli, Marco; Milani, E.; Prestopino, G.; Tucciarone, A.; Verona, C.; Verona-Rinati, G.; Angelone, M.; Pillon, M.; Dolbnya, I.; Sawhney, K.; Tartoni, N.

    2010-01-01

    Recently, solid state photovoltaic Schottky diodes, able to detect ionizing radiation, in particular, x-ray and ultraviolet radiation, have been developed at the University of Rome 'Tor Vergata'. We report on a physical and electrical properties analysis of the device and a detailed study of its detection capabilities as determined by its electrical properties. The design of the device is based on a metal/nominally intrinsic/p-type diamond layered structure obtained by microwave plasma chemical vapor deposition of homoepitaxial single crystal diamond followed by thermal evaporation of a metallic contact. The device can operate in an unbiased mode by using the built-in potential arising from the electrode-diamond junction. We compare the expected response of the device to photons of various energies calculated through Monte Carlo simulation with experimental data collected in a well controlled experimental setup i.e., monochromatic high flux x-ray beams from 6 to 20 keV, available at the Diamond Light Source synchrotron in Harwell (U.K.).

  9. Effect of radiation dose level on the detectability of pulmonary nodules in chest tomosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, Sara A.; Svalkvist, Angelica; Maansson, Lars Gunnar; Baath, Magnus [University of Gothenburg, Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg (Sweden); Sahlgrenska University Hospital, Department of Medical Physics and Biomedical Engineering, Gothenburg (Sweden); Johnsson, Aase A.; Vikgren, Jenny; Flinck, Agneta; Boijsen, Marianne; Fisichella, Valeria A. [University of Gothenburg, Department of Radiology, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg (Sweden); Sahlgrenska University Hospital, Department of Radiology, Gothenburg (Sweden)

    2014-07-15

    To investigate the detectability of pulmonary nodules in chest tomosynthesis at reduced radiation dose levels. Eighty-six patients were included in the study and were examined with tomosynthesis and computed tomography (CT). Artificial noise was added to simulate that the tomosynthesis images were acquired at dose levels corresponding to 12, 32, and 70 % of the default setting effective dose (0.12 mSv). Three observers (with >20, >20 and three years of experience) read the tomosynthesis cases for presence of nodules in a free-response receiver operating characteristics (FROC) study. CT served as reference. Differences between dose levels were calculated using the jack-knife alternative FROC (JAFROC) figure of merit (FOM). The JAFROC FOM was 0.45, 0.54, 0.55, and 0.54 for the 12, 32, 70, and 100 % dose levels, respectively. The differences in FOM between the 12 % dose level and the 32, 70, and 100 % dose levels were 0.087 (p = 0.006), 0.099 (p = 0.003), and 0.093 (p = 0.004), respectively. Between higher dose levels, no significant differences were found. A substantial reduction from the default setting dose in chest tomosynthesis may be possible. In the present study, no statistically significant difference in detectability of pulmonary nodules was found when reducing the radiation dose to 32 %. (orig.)

  10. Effect of radiation dose level on the detectability of pulmonary nodules in chest tomosynthesis

    International Nuclear Information System (INIS)

    Asplund, Sara A.; Svalkvist, Angelica; Maansson, Lars Gunnar; Baath, Magnus; Johnsson, Aase A.; Vikgren, Jenny; Flinck, Agneta; Boijsen, Marianne; Fisichella, Valeria A.

    2014-01-01

    To investigate the detectability of pulmonary nodules in chest tomosynthesis at reduced radiation dose levels. Eighty-six patients were included in the study and were examined with tomosynthesis and computed tomography (CT). Artificial noise was added to simulate that the tomosynthesis images were acquired at dose levels corresponding to 12, 32, and 70 % of the default setting effective dose (0.12 mSv). Three observers (with >20, >20 and three years of experience) read the tomosynthesis cases for presence of nodules in a free-response receiver operating characteristics (FROC) study. CT served as reference. Differences between dose levels were calculated using the jack-knife alternative FROC (JAFROC) figure of merit (FOM). The JAFROC FOM was 0.45, 0.54, 0.55, and 0.54 for the 12, 32, 70, and 100 % dose levels, respectively. The differences in FOM between the 12 % dose level and the 32, 70, and 100 % dose levels were 0.087 (p = 0.006), 0.099 (p = 0.003), and 0.093 (p = 0.004), respectively. Between higher dose levels, no significant differences were found. A substantial reduction from the default setting dose in chest tomosynthesis may be possible. In the present study, no statistically significant difference in detectability of pulmonary nodules was found when reducing the radiation dose to 32 %. (orig.)

  11. Application of random-point processes to the detection of radiation sources

    International Nuclear Information System (INIS)

    Woods, J.W.

    1978-01-01

    In this report the mathematical theory of random-point processes is reviewed and it is shown how use of the theory can obtain optimal solutions to the problem of detecting radiation sources. As noted, the theory also applies to image processing in low-light-level or low-count-rate situations. Paralleling Snyder's work, the theory is extended to the multichannel case of a continuous, two-dimensional (2-D), energy-time space. This extension essentially involves showing that the data are doubly stochastic Poisson (DSP) point processes in energy as well as time. Further, a new 2-D recursive formulation is presented for the radiation-detection problem with large computational savings over nonrecursive techniques when the number of channels is large (greater than or equal to 30). Finally, some adaptive strategies for on-line ''learning'' of unknown, time-varying signal and background-intensity parameters and statistics are present and discussed. These adaptive procedures apply when a complete statistical description is not available a priori

  12. Summary Report for the Radiation Detection for Nuclear Security Summer School 2014

    Energy Technology Data Exchange (ETDEWEB)

    Runkle, Robert C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Baciak, James E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodring, Mitchell L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jenno, Diana M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-09-01

    Executive Summary The Pacific Northwest National Laboratory (PNNL) hosted students from across the United States at the 3rd Radiation Detection for Nuclear Security Summer School from 16 – 27 June 2014. The summer school provided students with a unique understanding of nuclear security challenges faced in the field and exposed them to the technical foundations, analyses, and insight that will be required by future leaders in technology development and implementation. The course heavily emphasized laboratory and field demonstrations including direct measurements of special nuclear material. Student evaluations and feedback from student advisors indicates that the summer school achieved its objectives of 1) exposing students to the range of nuclear security applications for which radiation detection is necessary, 2) articulating the relevance of student research into the broader context, and 3) exciting students about the possibility of future careers in nuclear security. In fact, we are beginning to see previous students both enroll in graduate programs (former undergraduates) and complete internships at agencies like the National Nuclear Security Administration.

  13. Effect of ionizing radiation on the quantitative detection of Salmonella using real-time PCR

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sangyong; Jung, Jinwoo [Radiation Research Center for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kim, Minjeong; Ryu, Sangryeol [Department of Food and Animal Biotechnology, School of Agricultural Biotechnology, Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921 (Korea, Republic of); Kim, Dongho [Radiation Research Center for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of)], E-mail: fungikim@kaeri.re.kr

    2008-09-15

    Food irradiation is an economically viable technology for inactivating foodborne pathogens, but irradiation can mask pathogens in unhygienically prepared food. The aim of this study was to investigate the effect of irradiation treatment on the detection of Salmonella using real-time PCR. Three commercially available kits were tested, of which the InstaGene Matrix procedure was most effective in preparing template DNA from Salmonella exposed to radiation in broth culture. The minimum level of detection by real-time PCR combined with InstaGene Matrix was 3 log units of Salmonella per milliliter. However, when pure cultures of Salmonella were irradiated at 3 and 5 kGy, the cycle threshold (C{sub T}) increased 1-1.5-fold compared to irradiation at 0 and 1 kGy. This indicated that irradiation treatment may result in an underestimation of bacterial counts due to radiation-induced DNA lesions. We also compared C{sub T} values in inoculated chicken homogenates before and after irradiation, which in this model caused a 1.3-3.3-fold underestimation of bacterial counts with respect to irradiation dose.

  14. Effects of Ionizing Radiation on Biological Molecules—Mechanisms of Damage and Emerging Methods of Detection

    Science.gov (United States)

    Reisz, Julie A.; Bansal, Nidhi; Qian, Jiang; Zhao, Weiling

    2014-01-01

    Abstract Significance: The detrimental effects of ionizing radiation (IR) involve a highly orchestrated series of events that are amplified by endogenous signaling and culminating in oxidative damage to DNA, lipids, proteins, and many metabolites. Despite the global impact of IR, the molecular mechanisms underlying tissue damage reveal that many biomolecules are chemoselectively modified by IR. Recent Advances: The development of high-throughput “omics” technologies for mapping DNA and protein modifications have revolutionized the study of IR effects on biological systems. Studies in cells, tissues, and biological fluids are used to identify molecular features or biomarkers of IR exposure and response and the molecular mechanisms that regulate their expression or synthesis. Critical Issues: In this review, chemical mechanisms are described for IR-induced modifications of biomolecules along with methods for their detection. Included with the detection methods are crucial experimental considerations and caveats for their use. Additional factors critical to the cellular response to radiation, including alterations in protein expression, metabolomics, and epigenetic factors, are also discussed. Future Directions: Throughout the review, the synergy of combined “omics” technologies such as genomics and epigenomics, proteomics, and metabolomics is highlighted. These are anticipated to lead to new hypotheses to understand IR effects on biological systems and improve IR-based therapies. Antioxid. Redox Signal. 21: 260–292. PMID:24382094

  15. Detection of radiation treatment of meat by novel techniques of DNA comet assay

    International Nuclear Information System (INIS)

    Khan, A.A.; Khan, H.M.

    2002-01-01

    Treatment of food to ionizing radiation is being progressively used in many countries to inactivate food pathogens, to eradicate pests and to extend shelf life; thereby contributing to safer and more plentiful food supply. Food control agencies throughout the world need some reliable, simple and rapid methods for detection of irradiated foods to ensure free choice of consumer and to enforce labeling. The DNA comet assay offers great potential as a rapid tool to screen irradiated and unirradiated samples of several kinds of foods. In the present study, frozen beef has been investigated for detection of irradiation treatment. The samples were subjected to radiation doses of 0,4,5 and 7.0 kGy and were stored in freezer before analysis. The cells were extracted into cold PBS solutions, embedded into the agarose gel on microscope slides, lysed and electrophoressed at a voltage of 2v/cm for 2 min. The fragmented DNA as a result of irradiation treatment was stretched in the gel producing the dose dependent comets. These comets were visible using a simple transmission microscope after silver staining. The controlled and irradiated samples of meat were clearly distinguishable on the basis of the stained patterns of DNA in form of round or conical intact cells for unirradiated samples or in form of comets for irradiated samples. It is therefore, concluded that 'DNA Comet Assay' offers a potential to screen unirradiated and irradiated meat samples. (author)

  16. Fourier Transform Infrared Radiation Spectroscopy Applied for Wood Rot Decay and Mould Fungi Growth Detection

    Directory of Open Access Journals (Sweden)

    Bjørn Petter Jelle

    2012-01-01

    Full Text Available Material characterization may be carried out by the attenuated total reflectance (ATR Fourier transform infrared (FTIR radiation spectroscopical technique, which represents a powerful experimental tool. The ATR technique may be applied on both solid state materials, liquids, and gases with none or only minor sample preparations, also including materials which are nontransparent to IR radiation. This facilitation is made possible by pressing the sample directly onto various crystals, for example, diamond, with high refractive indices, in a special reflectance setup. Thus ATR saves time and enables the study of materials in a pristine condition, that is, the comprehensive sample preparation by pressing thin KBr pellets in traditional FTIR transmittance spectroscopy is hence avoided. Materials and their ageing processes, both ageing by natural and accelerated climate exposure, decomposition and formation of chemical bonds and products, may be studied in an ATR-FTIR analysis. In this work, the ATR-FTIR technique is utilized to detect wood rot decay and mould fungi growth on various building material substrates. An experimental challenge and aim is to be able to detect the wood rot decay and mould fungi growth at early stages when it is barely visible to the naked eye. Another goal is to be able to distinguish between various species of fungi and wood rot.

  17. Hypothesis tests for the detection of constant speed radiation moving sources

    Energy Technology Data Exchange (ETDEWEB)

    Dumazert, Jonathan; Coulon, Romain; Kondrasovs, Vladimir; Boudergui, Karim; Sannie, Guillaume; Gameiro, Jordan; Normand, Stephane [CEA, LIST, Laboratoire Capteurs Architectures Electroniques, 99 Gif-sur-Yvette, (France); Mechin, Laurence [CNRS, UCBN, Groupe de Recherche en Informatique, Image, Automatique et Instrumentation de Caen, 4050 Caen, (France)

    2015-07-01

    Radiation Portal Monitors are deployed in linear network to detect radiological material in motion. As a complement to single and multichannel detection algorithms, inefficient under too low signal to noise ratios, temporal correlation algorithms have been introduced. Test hypothesis methods based on empirically estimated mean and variance of the signals delivered by the different channels have shown significant gain in terms of a tradeoff between detection sensitivity and false alarm probability. This paper discloses the concept of a new hypothesis test for temporal correlation detection methods, taking advantage of the Poisson nature of the registered counting signals, and establishes a benchmark between this test and its empirical counterpart. The simulation study validates that in the four relevant configurations of a pedestrian source carrier under respectively high and low count rate radioactive background, and a vehicle source carrier under the same respectively high and low count rate radioactive background, the newly introduced hypothesis test ensures a significantly improved compromise between sensitivity and false alarm, while guaranteeing the stability of its optimization parameter regardless of signal to noise ratio variations between 2 to 0.8. (authors)

  18. Detection of electron and hole traps in CdZnTe radiation detectors by thermoelectric emission spectroscopy and thermally stimulated conductivity

    International Nuclear Information System (INIS)

    Lee, E.Y.; Brunett, B.A.; Olsen, R.W.; Van Scyoc, J.M. III; Hermon, H.; James, R.B.

    1998-01-01

    The electrical properties of CdZnTe radiation detectors are largely determined by electron and hole traps in this material. The traps, in addition to degrading the detector performance, can function as dopants and determine the resistivity of the material. Thermoelectric emission spectroscopy and thermally stimulated conductivity are used to detect these traps in a commercially available spectrometer-grade CdZnTe detector, and the electrical resistivity is measured as a function of temperature. A deep electron trap having an energy of 695 meV and cross section of 8 x 10 -16 cm 2 is detected and three hole traps having energies of 70 ± 20 meV, 105 ± 30 meV and 694 ± 162 meV are detected. A simple model based on these traps explains quantitatively all the data, including the electrical properties at room temperature and also their temperature dependence

  19. Ruggedization of CdZnTe detectors and detector assemblies for radiation detection applications

    Energy Technology Data Exchange (ETDEWEB)

    Lu, P.H., E-mail: pinghe.lu@redlen.com; Gomolchuk, P.; Chen, H.; Beitz, D.; Grosser, A.W.

    2015-06-01

    This paper described improvements in the ruggedization of CdZnTe detectors and detector assemblies for use in radiation detection applications. Research included experimenting with various conductive and underfill adhesive material systems suitable for CZT substrates. A detector design with encapsulation patterning was developed to protect detector surfaces and to control spacing between CZT anode and PCB carrier. Robustness of bare detectors was evaluated through temperature cycling and metallization shear testing. Attachment processes using well-chosen adhesives and PCB carrier materials were optimized to improve reliability of detector assemblies, resulted in Improved Attachment Detector Assembly. These detector assemblies were subjected to aggressive temperature cycling, and varying levels of drop/shock and vibration, in accordance with modified JEDEC, ANSI and FedEx testing standards, to assess their ruggedness. Further enhanced detector assembly ruggedization methods were investigated involving adhesive conformal coating, potting and dam filling on detector assemblies, which resulted in the Enhanced Ruggedization Detector Assembly. Large numbers of CZT detectors and detector assemblies with 5 mm and 15 mm thick, over 200 in total, were tested. Their performance was evaluated by exposure to various radioactive sources using comprehensive predefined detector specifications and testing protocols. Detector assemblies from improved attachment and enhanced ruggedization showed stable performances during the harsh environmental condition tests. In conclusion, significant progress has been made in improving the reliability and enhancing the ruggedness of CZT detector assemblies for radiation detection applications deployed in operational environments. - Highlights: • We developed ruggedization methods to enhance reliability of CZT detector assemblies. • Attachment of CZT radiation detectors was improved through comparative studies. • Bare detector metallization

  20. Detection of radiation induced lung injury in rats using dynamic hyperpolarized {sup 129}Xe magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Matthew S. [Department of Physics and Astronomy, Western University, London, Ontario, N6A 3K7, Canada and Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, N6A 5B7 (Canada); Ouriadov, Alexei; Hegarty, Elaine [Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, N6A 5B7 (Canada); Thind, Kundan [Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1, Canada and Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, N6A 5B7 (Canada); Wong, Eugene [Department of Physics and Astronomy, Western University, London, Ontario, N6A 3K7, Canada and London Regional Cancer Program, London, Ontario, N6C 2R6 (Canada); Hope, Andrew [Department of Radiation Oncology, University of Toronto, Toronto, Ontario, M5S 3E2, Canada and Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario, M5T 2M9 (Canada); Santyr, Giles E., E-mail: gsantyr@robarts.ca [Department of Medical Biophysics, Western University, London, Ontario, N6A 5C1 (Canada); Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, N6A 5B7 (Canada); Department of Medical Imaging, Western University, London, Ontario, N6A 5B7 (Canada)

    2014-07-15

    -irradiation, T{sub Tr-tissue} returned to values (35.6 ± 9.6 ms) that were not significantly different from baseline. Conclusions: Whole-lung tissue transfer time constants for{sup 129}Xe (T{sub Tr-tissue}) can be used to detect the early phase of RILI in a rat model involving 14 Gy thoracic {sup 60}Co exposure as early as two weeks post-irradiation. This knowledge combined with more sophisticated models of gas exchange and imaging techniques, may allow functional lung avoidance radiation therapy planning to be achievable, providing more beneficial treatment plans and improved quality of life for recovering lung cancer patients.

  1. Europa's surface radiation environment and considerations for in-situ sampling and biosignature detection

    Science.gov (United States)

    Nordheim, T.; Paranicas, C.; Hand, K. P.

    2017-12-01

    Jupiter's moon Europa is embedded deep within the Jovian magnetosphere and is thus exposed to bombardment by charged particles, from thermal plasma to more energetic particles at radiation belt energies. In particular, energetic charged particles are capable of affecting the uppermost layer of surface material on Europa, in some cases down to depths of several meters (Johnson et al., 2004; Paranicas et al., 2009, 2002). Examples of radiation-induced surface alteration include sputtering, radiolysis and grain sintering; processes that are capable of significantly altering the physical properties of surface material. Radiolysis of surface ices containing sulfur-bearing contaminants from Io has been invoked as a possible explanation for hydrated sulfuric acid detected on Europa's surface (Carlson et al., 2002, 1999) and radiolytic production of oxidants represents a potential source of energy for life that could reside within Europa's sub-surface ocean (Chyba, 2000; Hand et al., 2007; Johnson et al., 2003; Vance et al., 2016). Accurate knowledge of Europa's surface radiation environment is essential to the interpretation of space and Earth-based observations of Europa's surface and exosphere. Furthermore, future landed missions may seek to sample endogenic material emplaced on Europa's surface to investigate its chemical composition and to search for biosignatures contained within. Such material would likely be sampled from the shallow sub-surface, and thus, it becomes crucial to know to which degree this material is expected to have been radiation processed.Here we will present modeling results of energetic electron and proton bombardment of Europa's surface, including interactions between these particles and surface material. In addition, we will present predictions for biosignature destruction at different geographical locations and burial depths and discuss the implications of these results for surface sampling by future missions to Europa's surface.

  2. Performance of SEM scintillation detector evaluated by modulation transfer function and detective quantum efficiency function.

    Science.gov (United States)

    Bok, Jan; Schauer, Petr

    2014-01-01

    In the paper, the SEM detector is evaluated by the modulation transfer function (MTF) which expresses the detector's influence on the SEM image contrast. This is a novel approach, since the MTF was used previously to describe only the area imaging detectors, or whole imaging systems. The measurement technique and calculation of the MTF for the SEM detector are presented. In addition, the measurement and calculation of the detective quantum efficiency (DQE) as a function of the spatial frequency for the SEM detector are described. In this technique, the time modulated e-beam is used in order to create well-defined input signal for the detector. The MTF and DQE measurements are demonstrated on the Everhart-Thornley scintillation detector. This detector was alternated using the YAG:Ce, YAP:Ce, and CRY18 single-crystal scintillators. The presented MTF and DQE characteristics show good imaging properties of the detectors with the YAP:Ce or CRY18 scintillator, especially for a specific type of the e-beam scan. The results demonstrate the great benefit of the description of SEM detectors using the MTF and DQE. In addition, point-by-point and continual-sweep e-beam scans in SEM were discussed and their influence on the image quality was revealed using the MTF. © 2013 Wiley Periodicals, Inc.

  3. Adjusted functional boxplots for spatio-temporal data visualization and outlier detection

    KAUST Repository

    Sun, Ying; Genton, Marc G.

    2011-01-01

    This article proposes a simulation-based method to adjust functional boxplots for correlations when visualizing functional and spatio-temporal data, as well as detecting outliers. We start by investigating the relationship between the spatio

  4. Functional genetic research for radiation and drug resistant adenocarcinoma and its application

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Gyu; Kim, Kug Chan; Jung, Il Lae; Chul, Shin Byung; Kook, Park Hyo; Lee, Hee Min

    2012-01-15

    The work scope of 'Functional genetic research for radiation and drug resistant adenocarcinoma and its application' had contained the research about effect of transgelin(SM22a), neurotensin, metallothionein-1G transgelin-2 genes on the cell death triggered ionizing radiation, cisplatin, MMS, luteolin and H{sub 2}O{sub 2}(toxic agents), which are highly expressed in radiation-induced mutant cells. In this study, to elucidate the role of these proteins in the ionizing radiation (toxic chemicals)-induced cell death, we utilized sensed (or antisense, small interference RNA) cells, which overexpress (or down-regulate) RNAs associated with these proteins biosynthesis, and investigated the effects of these genes on the cytotoxicity caused by ionizing radiation, H{sub 2}O{sub 2} and toxic chemicals. We also investigated the functions of downstream target genes of transgelin such as IGF-1Rβ/PI3K/AKT pathway and transgelin/metallothioneine in A-549 and HepG2 cells because such target genes are able to potentiate the cell-killing or cell protecting effects against radiation.

  5. Functional genetic research for radiation and drug resistant adenocarcinoma and its application

    International Nuclear Information System (INIS)

    Kim, In Gyu; Kim, Kug Chan; Jung, Il Lae; Chul, Shin Byung; Kook, Park Hyo; Lee, Hee Min

    2012-01-01

    The work scope of 'Functional genetic research for radiation and drug resistant adenocarcinoma and its application' had contained the research about effect of transgelin(SM22a), neurotensin, metallothionein-1G transgelin-2 genes on the cell death triggered ionizing radiation, cisplatin, MMS, luteolin and H 2 O 2 (toxic agents), which are highly expressed in radiation-induced mutant cells. In this study, to elucidate the role of these proteins in the ionizing radiation (toxic chemicals)-induced cell death, we utilized sensed (or antisense, small interference RNA) cells, which overexpress (or down-regulate) RNAs associated with these proteins biosynthesis, and investigated the effects of these genes on the cytotoxicity caused by ionizing radiation, H 2 O 2 and toxic chemicals. We also investigated the functions of downstream target genes of transgelin such as IGF-1Rβ/PI3K/AKT pathway and transgelin/metallothioneine in A-549 and HepG2 cells because such target genes are able to potentiate the cell-killing or cell protecting effects against radiation

  6. Coniferyl aldehyde attenuates radiation enteropathy by inhibiting cell death and promoting endothelial cell function.

    Science.gov (United States)

    Jeong, Ye-Ji; Jung, Myung Gu; Son, Yeonghoon; Jang, Jun-Ho; Lee, Yoon-Jin; Kim, Sung-Ho; Ko, Young-Gyo; Lee, Yun-Sil; Lee, Hae-June

    2015-01-01

    Radiation enteropathy is a common complication in cancer patients. The aim of this study was to investigate whether radiation-induced intestinal injury could be alleviated by coniferyl aldehyde (CA), an HSF1-inducing agent that increases cellular HSP70 expression. We systemically administered CA to mice with radiation enteropathy following abdominal irradiation (IR) to demonstrate the protective effects of CA against radiation-induced gastrointestinal injury. CA clearly alleviated acute radiation-induced intestinal damage, as reflected by the histopathological data and it also attenuated sub-acute enteritis. CA prevented intestinal crypt cell death and protected the microvasculature in the lamina propria during the acute and sub-acute phases of damage. CA induced HSF1 and HSP70 expression in both intestinal epithelial cells and endothelial cells in vitro. Additionally, CA protected against not only the apoptotic cell death of both endothelial and epithelial cells but also the loss of endothelial cell function following IR, indicating that CA has beneficial effects on the intestine. Our results provide novel insight into the effects of CA and suggest its role as a therapeutic candidate for radiation-induced enteropathy due to its ability to promote rapid re-proliferation of the intestinal epithelium by the synergic effects of the inhibition of cell death and the promotion of endothelial cell function.

  7. Highly sensitive BTX detection using surface functionalized QCM sensor

    Energy Technology Data Exchange (ETDEWEB)

    Bozkurt, Asuman Aşıkoğlu; Özdemir, Okan; Altındal, Ahmet, E-mail: altindal@yildiz.edu.tr [Department of Physics, Yildiz Technical University, Davutpasa, 34210 Istanbul (Turkey)

    2016-03-25

    A novel organic compound was designed and successfully synthesized for the fabrication of QCM based sensors to detect the low concentrations of BTX gases in indoor air. The effect of the long-range electron orbital delocalization on the BTX vapour sensing properties of azo-bridged Pcs based chemiresistor-type sensors have also been investigated in this work. The sensing behaviour of the film for the online detection of volatile organic solvent vapors was investigated by utilizing an AT-cut quartz crystal resonator. It was observed that the adsorption of the target molecules on the coating surface cause a reversible negative frequency shift of the resonator. Thus, a variety of solvent vapors can be detected by using the phthalocyanine film as sensitive coating, with sensitivity in the ppm range and response times in the order of several seconds depending on the molecular structure of the organic solvent.

  8. Physicochemical and functional characteristics of radiation-processed shrimp chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Ocloo, F.C.K., E-mail: fidelis_ocloo@yahoo.co [Biotechnology and Nuclear Agriculture Research Institute, Ghana Atomic Energy Commission, P.O. Box LG 80, Legon (Ghana); Quayson, E.T. [Department of Biochemistry, University of Cape Coast, Cape Coast (Ghana); Adu-Gyamfi, A.; Quarcoo, E.A.; Asare, D. [Biotechnology and Nuclear Agriculture Research Institute, Ghana Atomic Energy Commission, P.O. Box LG 80, Legon (Ghana); Serfor-Armah, Y. [National Nuclear Research Institute, Ghana Atomic Energy Commission, P.O. Box LG 80, Legon (Ghana); Woode, B.K. [Department of Biochemistry, University of Cape Coast, Cape Coast (Ghana)

    2011-07-15

    The effects of gamma irradiation on chitosan samples were determined in terms of physicochemical and functional properties. Shrimp chitosan was extracted from shell using a chemical process involving demineralization, deproteinization, decolorization and deacetylation. Commercial snow chitosan was also used. Samples (in a solid state) were given irradiation dose of 25 kGy at a dose rate of 1.1013 kGy/h in air and 0 kGy samples were used as controls. Results showed that moisture contents were between 8.690% and 13.645%. There were no significant differences (P>0.05) in the degree of deacetylation of the chitosan samples. Significant differences (P<0.05) were observed in the viscosity and viscosity-average molecular weight of the chistosan samples. Viscosity and molecular weight decreased when the samples were given the irradiation dose of 25 kGy. Chitosan samples had low antioxidant activity compared with BHT. Water binding capacity ranged from 582.40% to 656.75% and fat binding capacity was between 431.00% and 560.55%. Irradiation had a major effect on the viscosity and the viscosity-average molecular weight of the chitosan samples.

  9. Physicochemical and functional characteristics of radiation-processed shrimp chitosan

    International Nuclear Information System (INIS)

    Ocloo, F.C.K.; Quayson, E.T.; Adu-Gyamfi, A.; Quarcoo, E.A.; Asare, D.; Serfor-Armah, Y.; Woode, B.K.

    2011-01-01

    The effects of gamma irradiation on chitosan samples were determined in terms of physicochemical and functional properties. Shrimp chitosan was extracted from shell using a chemical process involving demineralization, deproteinization, decolorization and deacetylation. Commercial snow chitosan was also used. Samples (in a solid state) were given irradiation dose of 25 kGy at a dose rate of 1.1013 kGy/h in air and 0 kGy samples were used as controls. Results showed that moisture contents were between 8.690% and 13.645%. There were no significant differences (P>0.05) in the degree of deacetylation of the chitosan samples. Significant differences (P<0.05) were observed in the viscosity and viscosity-average molecular weight of the chistosan samples. Viscosity and molecular weight decreased when the samples were given the irradiation dose of 25 kGy. Chitosan samples had low antioxidant activity compared with BHT. Water binding capacity ranged from 582.40% to 656.75% and fat binding capacity was between 431.00% and 560.55%. Irradiation had a major effect on the viscosity and the viscosity-average molecular weight of the chitosan samples.

  10. Radiative corrections for the direct detection of neutralino dark matter and its relic density

    Energy Technology Data Exchange (ETDEWEB)

    Steppeler, Patrick Norbert

    2016-07-01

    In this thesis we calculate supersymmetric one-loop corrections of the strong interaction to elastic neutralino-nucleon scattering. The calculation is described in detail and performed in full generality within the Minimal Supersymmetric Standard Model (MSSM). In order to benefit from the well-established tensor reduction method, we have to stabilise the latter for vanishing Gram determinants. Afterwards the radiative corrections are matched onto an effective field theory based on the scalar operator anti χχ anti qq and the axial-vector operator anti χγ{sub 5}γ{sub μ}χ anti qγ{sub 5}γ{sup μ}q. This matching procedure is performed at the high scale μ{sub high}∝1000 GeV, whereas the associated nuclear matrix elements are defined at the low scale μ{sub low}∝5 GeV. To link both scales, the running of the effective operators and their corresponding Wilson coefficients is taken into account via renormalisation group equations. The lightest neutralino can be considered as a canonical example for a weakly interacting, massive particle which could constitute dark matter. To verify the existence of such particles, so-called direct detection experiments are conducted currently. These are based on the interaction between dark matter and nucleons. The leading contributions to the spin-independent and spin-dependent neutralino-nucleon cross sections are governed by the effective operators mentioned above, respectively. The calculation of the associated radiative corrections corresponds to a reduction of the theoretical uncertainty and permits to identify neutralino properties more reliably in case of positive findings and to set more robust exclusion bounds in case of negative findings. Furthermore, we calculate radiative corrections to annihilation and coannihilation processes of gauginos into quarks, where we focus again on supersymmetric one-loop corrections of the strong interaction. These processes contribute dominantly to the (co)annihilation cross section

  11. New functionality of chalcogenide glasses for radiation sensing of nuclear wastes.

    Science.gov (United States)

    Ailavajhala, M S; Gonzalez-Velo, Y; Poweleit, C D; Barnaby, H J; Kozicki, M N; Butt, D P; Mitkova, M

    2014-03-30

    Data about gamma radiation induced effects in Ge40Se60 chalcogenide thin films and radiation induced silver diffusion within these are presented. Blanket films and devices were created to study the structural changes, diffusion products, and device performance. Raman spectroscopy, X-ray diffraction, current vs. voltage (I-V) and impedance measurements expound the behavior of Ge40Se60 glass and silver diffusion within this glass under radiation. Raman study shows that there is a decrease in the area ratio between edge shared and corner shared structural units revealing structural reorganization occurring in the glasses as a result of gamma radiation. X-ray diffraction studies revealed that with sufficiently radiation dose it is also possible to create Ag2Se in selenium-depleted systems. Oxidation of the Ge enriched chalcogenide backbone is confirmed through the electrical performance of the sensing elements based on these films. Combination of these structural and diffusion products influences the device performance. The I-V behavior is characterized by increase in current and then stabilization as a function of radiation dose. Additionally, device modeling is also presented using Silvaco software and analytical methods to shed light on the device behavior. This type of sensor design and material characterizations facilitate in improving the radiation sensing capabilities of silver containing chalcogenide glass thin films. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Radiation therapy for prostate cancer and erectile (dys)function: The role of imaging

    Energy Technology Data Exchange (ETDEWEB)

    Incrocci, Luca [Erasmus MC-Daniel den Hoed Cancer Center, Rotterdam (Netherlands). Dept. of Radiation Oncology

    2005-10-01

    Incidence of erectile dysfunction (ED) after radiotherapy reported in the literature varies from 7 to 72% after external-beam radiotherapy to 5-51% after brachytherapy. Most of these studies are retrospective, the definition of ED is variable and sexual functioning is frequently assessed by asking only one question. Already in the 1980's it was suggested that post-radiation ED was attributable to vascular damage. The most reliable method to assess vasculogenic ED is the use of the Doppler ultrasound. More recently, many studies have assessed the relationship between radiation dose and volume of the penile bulb and post-radiation ED, though the outcome is controversial. The penile structures and the neurovascular bundles are best seen on magnetic resonance imaging (MRI). Therefore the use of a computer tomography scan/MRI image fusion can result in reducing the planning target volume and consequently the radiation dose to the penile bulb and bodies. If radiation induces vascular damage that causes ED, any means of reducing the dose to the pelvic vascular structures would likely decrease ED, therefore new radiation techniques such as the intensity modulated radiation therapy or the implant of fiducial markers can help decrease the margins and therefore ED.

  13. Using Loss Functions for DIF Detection: An Empirical Bayes Approach.

    Science.gov (United States)

    Zwick, Rebecca; Thayer, Dorothy; Lewis, Charles

    2000-01-01

    Studied a method for flagging differential item functioning (DIF) based on loss functions. Builds on earlier research that led to the development of an empirical Bayes enhancement to the Mantel-Haenszel DIF analysis. Tested the method through simulation and found its performance better than some commonly used DIF classification systems. (SLD)

  14. Optimal threshold functions for fault detection and isolation

    DEFF Research Database (Denmark)

    Stoustrup, J.; Niemann, Hans Henrik; Cour-Harbo, A. la

    2003-01-01

    Fault diagnosis systems usually comprises two parts: a filtering part and a decision part, the latter typically based on threshold functions. In this paper, systematic ways to choose the threshold values are proposed. Two different test functions for the filtered signals are discussed and a method...

  15. Radiofrequency electromagnetic radiation from cell phone causes defective testicular function in male Wistar rats.

    Science.gov (United States)

    Oyewopo, A O; Olaniyi, S K; Oyewopo, C I; Jimoh, A T

    2017-12-01

    Cell phones have become an integral part of everyday life. As cell phone usage has become more widespread, concerns have increased regarding the harmful effects of radiofrequency electromagnetic radiation from these devices. The current study was undertaken to investigate the effects of the emitted radiation by cell phones on testicular histomorphometry and biochemical analyses. Adult male Wistar rats weighing 180-200 g were randomly allotted to control, group A (switched off mode exposure), group B (1-hr exposure), group C (2-hr exposure) and group D (3-hr exposure). The animals were exposed to radiofrequency electromagnetic radiation of cell phone for a period of 28 days. Histomorphometry, biochemical and histological investigations were carried out. The histomorphometric parameters showed no significant change (p electromagnetic radiation of cell phone leads to defective testicular function that is associated with increased oxidative stress and decreased gonadotropic hormonal profile. © 2017 Blackwell Verlag GmbH.

  16. Open-Source Radiation Exposure Extraction Engine (RE3) with Patient-Specific Outlier Detection.

    Science.gov (United States)

    Weisenthal, Samuel J; Folio, Les; Kovacs, William; Seff, Ari; Derderian, Vana; Summers, Ronald M; Yao, Jianhua

    2016-08-01

    We present an open-source, picture archiving and communication system (PACS)-integrated radiation exposure extraction engine (RE3) that provides study-, series-, and slice-specific data for automated monitoring of computed tomography (CT) radiation exposure. RE3 was built using open-source components and seamlessly integrates with the PACS. RE3 calculations of dose length product (DLP) from the Digital imaging and communications in medicine (DICOM) headers showed high agreement (R (2) = 0.99) with the vendor dose pages. For study-specific outlier detection, RE3 constructs robust, automatically updating multivariable regression models to predict DLP in the context of patient gender and age, scan length, water-equivalent diameter (D w), and scanned body volume (SBV). As proof of concept, the model was trained on 811 CT chest, abdomen + pelvis (CAP) exams and 29 outliers were detected. The continuous variables used in the outlier detection model were scan length (R (2)  = 0.45), D w (R (2) = 0.70), SBV (R (2) = 0.80), and age (R (2) = 0.01). The categorical variables were gender (male average 1182.7 ± 26.3 and female 1047.1 ± 26.9 mGy cm) and pediatric status (pediatric average 710.7 ± 73.6 mGy cm and adult 1134.5 ± 19.3 mGy cm).

  17. Results of conservative surgery and radiation for mammographically detected ductal carcinoma in situ (DCIS)

    International Nuclear Information System (INIS)

    Fowble, B.; Hanlon, A.L.; Fein, D.A.; Hoffman, J.P.; Sigurdson, E.R.; Patchefsky, A.; Kessler, H.

    1996-01-01

    Purpose: The role of conservative surgery and radiation for mammographically detected DCIS is controversial. In particular, there is a paucity of data for outcome with radiation in a group of patients comparable to those treated with local excision and surveillance (mammographically detected DCIS ≤2.5 cm, negative resection margins, negative post-biopsy mammogram). The purpose of this study is to report long term outcome of conservative surgery and radiation for mammographically detected DCIS with emphasis on the results in patients (pts.) considered candidates for excision alone. Materials and Methods: From 1983 to 1992, 110 women with mammographically detected DCIS (calcifications 72%, mass ± calcifications 27%) and no prior history of breast cancer underwent needle localization biopsy followed by radiation. The median age of the patient population was 56 yrs. (range 37-81). The median followup was 5.3 yrs. (range .5-12). Re-excision was performed in 55%. Final margins of resection were negative in 62%, positive 7%, close 11%, and unknown 20%. Axillary dissection was performed in 31 pts. and all had negative nodes. 31% had a positive family history of breast cancer (1 affected relative-25 pts., two-7 pts., three-2 pts.). The most common predominant histologic subtype was comedo (54%) followed by cribriform (22%). The median pathologic tumor size was 8 mm (range 2 mm to 5 cm). A post-biopsy mammogram prior to radiation was performed in 46% of the patients. Radiation consisted of treatment to the entire breast (median 5000 cGy) with a boost to the primary site (97%) of an additional 1000 cGy. The median total dose to the primary site was 6040 cGy (range 5000 to 6660). Results: Three patients developed a recurrence in the treated breast at 52, 106, and 107 months. All 3 recurrences were invasive ductal cancers and all were treated with mastectomy. The location of the recurrence was in the same quadrant as the primary in 1 pt. and in a separate quadrant in 2 pts

  18. Functional signatures of radio-induction in sarcomas developing in the radiation field after radiotherapy

    International Nuclear Information System (INIS)

    Hadj-Hamou, N.S.

    2010-01-01

    Radiotherapy plays an important role in the treatment of cancers. However, exposure to ionizing radiation is a well-known risk factor for secondary cancer development. Currently, rigorous defined scientific criteria are lacking to establish if an individual tumor has a radiation-induced or a sporadic origin. The main aim of my thesis program was to identify a transcriptome signature of the ionizing radiation effects in radiation-induced cancers. The series of cancers used in this study is composed of sarcomas developing in the irradiation field of patients treated by radiotherapy for a primary cancer. Strict selection criteria (histology different from the primary cancer, latency longer than 5 years) were used to establish with a high probability the sarcomas-radiation induced origin. Their transcriptomes were compared with those from patients without irradiation history. A method of classification adapted to small series was used for the study of all the 60 collected sarcomas (34 radiation-induced and 26 sporadic). A learning set composed of 24 sarcomas from known aetiology allowed us to determine a signature of 135 genes discriminating the sarcomas according to their aetiology. The signature classified 86% of the remaining sarcomas as a function of their aetiology with an accuracy of 97%. The analysis of the genes-function shows that the radiation-induced sarcomas suffered the effects of a chronic oxidative stress mainly generated by mitochondrial dysfunctions. This study shows, for the first time, that it is possible to diagnose, at the case by case level, radiation-induced sarcomas on a rigorous scientific basis. (author)

  19. Pulsed radiation decay logging

    International Nuclear Information System (INIS)

    Mills, W.R. Jr.

    1983-01-01

    There are provided new and improved well logging processes and systems wherein the detection of secondary radiation is accomplished during a plurality of time windows in a manner to accurately characterize the decay rate of the secondary radiation. The system comprises a well logging tool having a primary pulsed radiation source which emits repetitive time-spaced bursts of primary radiation and detector means for detecting secondary radiation resulting from the primary radiation and producing output signals in response to the detected radiation. A plurality of measuring channels are provided, each of which produces a count rate function representative of signals received from the detector means during successive time windows occurring between the primary radiation bursts. The logging system further comprises means responsive to the measuring channels for producing a plurality of functions representative of the ratios of the radiation count rates measured during adjacent pairs of the time windows. Comparator means function to compare the ratio functions and select at least one of the ratio functions to generate a signal representative of the decay rate of the secondary radiation

  20. Visual outcome, endocrine function and tumor control after fractionated stereotactic radiation therapy of craniopharyngiomas in adults

    DEFF Research Database (Denmark)

    Astradsson, Arnar; Munck Af Rosenschöld, Per; Feldt-Rasmussen, Ulla

    2017-01-01

    BACKGROUND: The purpose of this study was to examine visual outcome, endocrine function and tumor control in a prospective cohort of craniopharyngioma patients, treated with fractionated stereotactic radiation therapy (FSRT). MATERIAL AND METHODS: Sixteen adult patients with craniopharyngiomas were...... eligible for analysis. They were treated with linear accelerator-based FSRT during 1999-2015. In all cases, diagnosis was confirmed by histological analysis. The prescription dose to the tumor was 54 Gy (median, range 48-54) in 1.8 or 2.0 Gy per fraction, and the maximum radiation dose to the optic nerves.......7-13.1) for visual outcome, endocrine function, and tumor control, respectively. RESULTS: Visual acuity impairment was present in 10 patients (62.5%) and visual field defects were present in 12 patients (75%) before FSRT. One patient developed radiation-induced optic neuropathy at seven years after FSRT. Thirteen...