WorldWideScience

Sample records for natural space radiation

  1. Modeling Natural Space Ionizing Radiation Effects on External Materials

    Science.gov (United States)

    Alstatt, Richard L.; Edwards, David L.; Parker, Nelson C. (Technical Monitor)

    2000-01-01

    Predicting the effective life of materials for space applications has become increasingly critical with the drive to reduce mission cost. Programs have considered many solutions to reduce launch costs including novel, low mass materials and thin thermal blankets to reduce spacecraft mass. Determining the long-term survivability of these materials before launch is critical for mission success. This presentation will describe an analysis performed on the outer layer of the passive thermal control blanket of the Hubble Space Telescope. This layer had degraded for unknown reasons during the mission, however ionizing radiation (IR) induced embrittlement was suspected. A methodology was developed which allowed direct comparison between the energy deposition of the natural environment and that of the laboratory generated environment. Commercial codes were used to predict the natural space IR environment model energy deposition in the material from both natural and laboratory IR sources, and design the most efficient test. Results were optimized for total and local energy deposition with an iterative spreadsheet. This method has been used successfully for several laboratory tests at the Marshall Space Flight Center. The study showed that the natural space IR environment, by itself, did not cause the premature degradation observed in the thermal blanket.

  2. Basic mechanisms of radiation effects in the natural space radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    Schwank, J.R.

    1994-06-01

    Four general topics are covered in respect to the natural space radiation environment: (1) particles trapped by the earth`s magnetic field, (2) cosmic rays, (3) radiation environment inside a spacecraft, (4) laboratory radiation sources. The interaction of radiation with materials is described by ionization effects and displacement effects. Total-dose effects on MOS devices is discussed with respect to: measurement techniques, electron-hole yield, hole transport, oxide traps, interface traps, border traps, device properties, case studies and special concerns for commercial devices. Other device types considered for total-dose effects are SOI devices and nitrided oxide devices. Lastly, single event phenomena are discussed with respect to charge collection mechanisms and hard errors. (GHH)

  3. On-orbit radiography of space vehicles using natural radiation

    Science.gov (United States)

    Priedhorsky, William C.; Ransom, Scott M.

    2004-01-01

    We demonstrate that 80-140 keV hard X-rays from the X-ray star Cygnus X-1 could be used, in principle, to image the interior of an unknown target spacecraft. A simulated radiograph shows good signal-to-noise in a 1000-second exposure with ~2 cm spatial resolution. Because of the high collimation and short wavelength of the radiation, an image can be formed at almost any target-detector distance. Practical application of the technique would require the detector spacecraft to assume a parallel trajectory with the target and maintain station accurately enough to hold the radiograph shadow on its sensitive surface. Further research is needed on 1) detector background minimization in high-latitude and high-altitude orbits; 2) image formation for rotating targets, which is a problem similar to computerized tomography; and 3) optimization of navigation and station-keeping.

  4. Space Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R.

    1968-01-01

    This booklet discusses three kinds of space radiation, cosmic rays, Van Allen Belts, and solar plasma. Cosmic rays are penetrating particles that we cannot see, hear or feel, which come from distant stars. Van Allen Belts, named after their discoverer are great belts of protons and electrons that the earth has captured in its magnetic trap. Solar plasma is a gaseous, electrically neutral mixture of positive and negative ions that the sun spews out from convulsed regions on its surface.

  5. Space Flight Ionizing Radiation Environments

    Science.gov (United States)

    Koontz, Steve

    2017-01-01

    The space-flight ionizing radiation (IR) environment is dominated by very high-kinetic energy-charged particles with relatively smaller contributions from X-rays and gamma rays. The Earth's surface IR environment is not dominated by the natural radioisotope decay processes. Dr. Steven Koontz's lecture will provide a solid foundation in the basic engineering physics of space radiation environments, beginning with the space radiation environment on the International Space Station and moving outward through the Van Allen belts to cislunar space. The benefits and limitations of radiation shielding materials will also be summarized.

  6. Radiation effects in space

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1987-07-01

    As more people spend more time in space, and the return to the moon and exploratory missions are considered, the risks require continuing examination. The effects of microgravity and radiation are two potential risks in space. These risks increase with increasing mission duration. This document considers the risk of radiation effects in space workers and explorers. 17 refs., 1 fig., 4 tabs

  7. Radiation effects in space

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1986-01-01

    The paper discusses the radiation environment in space that astronauts are likely to be exposed to. Emphasis is on proton and HZE particle effects. Recommendations for radiation protection guidelines are presented

  8. Space Radiation Risk Assessment

    Data.gov (United States)

    National Aeronautics and Space Administration — Project A: Integration and Review: A review of current knowledge from space radiation physics was accepted for publication in Reviews of Modern Physics (Durante and...

  9. Exposure to natural radiation

    International Nuclear Information System (INIS)

    Green, B.M.R.

    1985-01-01

    A brief report is given of a seminar on the exposure to enhanced natural radiation and its regulatory implications held in 1985 at Maastricht, the Netherlands. The themes of the working sessions included sources of enhanced natural radiation, parameters influencing human exposure, measurement and survey programmes, technical countermeasures, risk and assessment studies, philosophies of dose limitations and national and international policies. (U.K.)

  10. Exposure to natural radiation from the earth's crust, atmosphere and outer space - the natural radioactivity of the earth's crust

    International Nuclear Information System (INIS)

    Schwab, R.G.

    1987-01-01

    Any conclusions to be drawn from the geochemical distribution pattern of radioactive elements for one's own conduct require to study their distribution in soil, earth crust, magmatic differentiation, rock disintegration zone and biosphere. The author notes that high activities in soils and rocks are contrasted by relatively low radiation dose levels absorbed by the human body. This is different for incorporated radiation. (DG) [de

  11. The natural radiation background

    International Nuclear Information System (INIS)

    Duggleby, J.C.

    1982-01-01

    The components of the natural background radiation and their variations are described. Cosmic radiation is a major contributor to the external dose to the human body whilst naturally-occurring radionuclides of primordial and cosmogenic origin contribute to both the external and internal doses, with the primordial radionuclides being the major contributor in both cases. Man has continually modified the radiation dose to which he has been subjected. The two traditional methods of measuring background radiation, ionisation chamber measurements and scintillation counting, are looked at and the prospect of using thermoluminescent dosimetry is considered

  12. NASA Space Radiation Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory is a NASA funded facility, delivering heavy ion beams to a target area where scientists...

  13. Natural radiation environment III

    International Nuclear Information System (INIS)

    Gesell, T.F.; Lowder, W.M.

    1980-01-01

    Separate abstracts were prepared for the 52 research papers presented at this symposium in April 1978. The major topics in this volume deal with penetrating radiation measurements, radiation surveys and population exposure, radioactivity in the indoor environment, and technologically enhanced natural radioactivity

  14. Radiative transfer on discrete spaces

    CERN Document Server

    Preisendorfer, Rudolph W; Stark, M; Ulam, S

    1965-01-01

    Pure and Applied Mathematics, Volume 74: Radiative Transfer on Discrete Spaces presents the geometrical structure of natural light fields. This book describes in detail with mathematical precision the radiometric interactions of light-scattering media in terms of a few well established principles.Organized into four parts encompassing 15 chapters, this volume begins with an overview of the derivations of the practical formulas and the arrangement of formulas leading to numerical solution procedures of radiative transfer problems in plane-parallel media. This text then constructs radiative tran

  15. Natural radiation environment III

    International Nuclear Information System (INIS)

    Gesell, T.F.; Lowder, W.M.

    1980-01-01

    Separate abstracts were prepared for the 57 research papers presented at this symposium in April 1978 at Houston, Texas. This symposium provided a common forum for scientists in several disciplines that deal with natural radiation because there is an increasing interest in the environment as it pertains to human health and the competition for scarce energy and material resources

  16. Modeling Space Radiation with Bleomycin

    Data.gov (United States)

    National Aeronautics and Space Administration — Space radiation is a mixed field of solar particle events (proton) and particles of Galactic Cosmic Rays (GCR) with different energy levels. These radiation events...

  17. Radiations and space flight

    International Nuclear Information System (INIS)

    Maalouf, M.; Vogin, G.; Foray, N.; Maalouf; Vogin, G.

    2011-01-01

    A space flight is submitted to 3 main sources of radiation: -) cosmic radiation (4 protons/cm 2 /s and 10000 times less for the heaviest particles), -) solar radiation (10 8 protons/cm 2 /s in the solar wind), -) the Van Allen belt around the earth: the magnetosphere traps particles and at an altitude of 500 km the proton flux can reach 100 protons/cm 2 /s. If we take into account all the spatial missions performed since 1960, we get an average dose of 400 μGray per day with an average dose rate of 0.28 μGray/mn. A significant risk of radiation-induced cancer is expected for missions whose duration is over 250 days.The cataract appears to be the most likely non-cancerous health hazard due to the exposition to comic radiation. Its risk appears to have been under-estimated, particularly for doses over 8 mGray. Some studies on astronauts have shown for some a very strong predisposition for radio-induced cancers: during the reparation phase of DNA breaking due to irradiation, multiple new damages are added by the cells themselves that behave abnormally. (A.C.)

  18. Space Radiation Dosimetry

    International Nuclear Information System (INIS)

    Deme, S.

    2003-01-01

    Although partly protected from galactic and solar cosmic radiation by the Earth's magnetosphere in Low Earth Orbit (LEO) astronauts exposure levels during long-term missions (90 days to 180 days) by far exceed with exposures of up to more than 100 mSv the annual exposure limits set for workers in the nuclear industry, but are still below the yearly exposure limits of 500 mSv for NASA astronauts. During solar particle events the short-term limits (300 mSv) may be approached or even exceeded. In the interplanetary space, outside the Earth's magnetic field even relatively benign Solar Particle Events (SPEs) can produce 1 Sv skin-absorbed doses. Although new rocket technologies could reduce astronauts' total exposure to space radiation during a human Mars mission, the time required for the mission, which is now in the order of years. Therefore mission planners will need to consider a variety of countermeasures for the crew members including physical protection (e.g. shelters), active protection (e.g. magnetic protection), pharmacological protection, local protection (extra protection for critical areas of the body) etc. With full knowledge of these facts, accurate personal dose measurement will become increasingly important during human missions to Mars. The new dose limits for radiation workers correspond to excess lifetime risk of 3% (NCRP) and 4% (ICRP). While astronauts accept the whole variety of flight risks they are taking in mission, there is concern about risks that may occur later in life. A risk no greater than the risk of radiation workers would be acceptable. (author)

  19. Thermoluminescent measurement in space radiation dosimetry

    International Nuclear Information System (INIS)

    Chen Mei; Qi Zhangnian; Li Xianggao; Huang Zengxin; Jia Xianghong; Wang Genliang

    1999-01-01

    The author introduced the space radiation environment and the application of thermoluminescent measurement in space radiation dosimetry. Space ionization radiation is charged particles radiation. Space radiation dosimetry was developed for protecting astronauts against space radiation. Thermoluminescent measurement is an excellent method used in the spaceship cabin. Also the authors mentioned the recent works here

  20. Radiation risk in space exploration

    International Nuclear Information System (INIS)

    Schimmerling, W.; Wilson, J.W.; Cucinotta, F.; Kim, M.H.Y.

    1997-01-01

    Humans living and working in space are exposed to energetic charged particle radiation due to galactic cosmic rays and solar particle emissions. In order to keep the risk due to radiation exposure of astronauts below acceptable levels, the physical interaction of these particles with space structures and the biological consequences for crew members need to be understood. Such knowledge is, to a large extent, very sparse when it is available at all. Radiation limits established for space radiation protection purposes are based on extrapolation of risk from Japanese survivor data, and have been found to have large uncertainties. In space, attempting to account for large uncertainties by worst-case design results in excessive costs and accurate risk prediction is essential. It is best developed at ground-based laboratories, using particle accelerator beams to simulate individual components of space radiation. Development of mechanistic models of the action of space radiation is expected to lead to the required improvements in the accuracy of predictions, to optimization of space structures for radiation protection and, eventually, to the development of biological methods of prevention and intervention against radiation injury. (author)

  1. Teaching about Natural Background Radiation

    Science.gov (United States)

    Al-Azmi, Darwish; Karunakara, N.; Mustapha, Amidu O.

    2013-01-01

    Ambient gamma dose rates in air were measured at different locations (indoors and outdoors) to demonstrate the ubiquitous nature of natural background radiation in the environment and to show that levels vary from one location to another, depending on the underlying geology. The effect of a lead shield on a gamma radiation field was also…

  2. Natural sources of ionizing radiations

    International Nuclear Information System (INIS)

    Marej, A.N.

    1984-01-01

    Natural sources of ionizing radiations are described in detail. The sources are subdivided into sources of extraterrestrial origin (cosmic radiation) and sources of terrestrial origin. Data on the concentration of different nuclides in rocks, various soils, ground waters, atmospheric air, tissues of plants and animals, various food stuffs are presented. The content of natural radionuclides in environmental objects, related to human activities, is discussed

  3. Radiation stability of animate nature

    International Nuclear Information System (INIS)

    Romanov, G.N.; Spirin, D.A.

    1990-01-01

    The main principles of radiation safety for animate nature including provisions for biological species protection and main requirement for animate nature radiation protection, which is the guarantee of any ecosystem integrity, are discussed. Ecosystem should be taken as the objective unit for animate nature radiation protection. The maximum dose of biot irradiation may amount to 0.5 Gy/year, which is 20-fold lower than the main dose limit for animate nature and 40-fold lower than ecological dose limits for conifers as the weakest radiostable member in ecosystem, at environment radioactive contamination determined by radiation safety standards. The radiation protection of animate nature is guaranteed at such levels of environment radioactive contamination

  4. Biology relevant to space radiation

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1996-01-01

    The biological effects of the radiations to which mankind on earth are exposed are becoming known with an increasing degree of detail. This knowledge is the basis of the estimates of risk that, in turn, fosters a comprehensive and evolving radiation protection system. The substantial body of information has been, and is being, applied to questions about the biological effects of radiation is space and the associated risk estimates. The purpose of this paper is not to recount all the biological effect of radiation but to concentrate on those that may occur as a result from exposure to the radiations encountered in space. In general, the biological effects of radiation in space are the same as those on earth. However, the evidence that the effects on certain tissues by the heaviest-charged particles can be interpreted on the basis of our knowledge about other high-LET radiation is equivocal. This specific question will be discussed in greater detail later. It is important to point out the that there are only limited data about the effects on humans of two components of the radiations in space, namely protons and heavy ions. Thus predictions of effects on space crews are based on experimental systems exposed on earth at rates and fluences that are higher than those in space and one the effects of gamma or x rays with estimates of the equivalent doses using quality factors

  5. Measuring space radiation shielding effectiveness

    OpenAIRE

    Bahadori Amir; Semones Edward; Ewert Michael; Broyan James; Walker Steven

    2017-01-01

    Passive radiation shielding is one strategy to mitigate the problem of space radiation exposure. While space vehicles are constructed largely of aluminum, polyethylene has been demonstrated to have superior shielding characteristics for both galactic cosmic rays and solar particle events due to the high hydrogen content. A method to calculate the shielding effectiveness of a material relative to reference material from Bragg peak measurements performed using energetic heavy charged particles ...

  6. Space radiation and astronaut safety

    CERN Document Server

    Seedhouse, Erik

    2018-01-01

    This brief explores the biological effects of long-term radiation on astronauts in deep space. As missions progress beyond Earth's orbit and away from the protection of its magnetic shielding, astronauts risk constant exposure to higher levels of galactic cosmic rays and solar particle events. The text concisely addresses the full spectrum of biomedical consequences from exposure to space radiation and goes on to present possible ways to mitigate such dangers and protect astronauts within the limitations of existing technologies.

  7. The natural radiation environment: future perspective

    International Nuclear Information System (INIS)

    Steinhaeusler, F.

    1992-01-01

    The need to control the exposure of man to the natural radiation environment (NRE) is increasingly recognised. The main NRE sources and exposure situations warranting intensified efforts in the future are: exposure to radiation in space (astronaut: ≤ 1 mSv.d -1 ), technologically enhanced natural radiation (TENR; global impact: 400,000 man.Sv.y -1 ) and populations living in high background radiation areas (resident: ≤ 360 mGy.y -1 ). Data on NRE-TENR-induced biological effects are scarce and inconclusive, such as increased frequency of chromosome aberrations and mental retardation from environmental gamma radiation, but there are contradictory results for thorium and radon exposure induced lung cancer risk. Four coordinated actions are proposed, i.e. international standardisation of methods, coordination of multidisciplinary health effect studies, development of principles for NRE/TENR control, and establishment of an international clearing house for all NRE-related topics. (Author)

  8. Natural radiation in the environment

    International Nuclear Information System (INIS)

    Moeller, D.W.

    1990-01-01

    The speaker discusses natural radiation in the environment. He outlines the external sources of exposure (cosmic and terrestrial), as well as the internal sources (ingestion and inhalation). He states that a clear understanding of these sources and their impacts is necessary in order to properly evaluate both the environment and human radiation exposure

  9. Radiation processing of natural polymer

    International Nuclear Information System (INIS)

    Khairul Zaman; Kamaruddin Hashim; Zulkafli Ghazali; Mohd Hilmi Mahmood; Jamaliah Sharif

    2006-01-01

    Radiation processing of natural polymer has been the subject of interest of countries in this region in the past 5 ∼ 7 years. Although some of the output of the research have been commercialized in particular for the applications in the agriculture and healthcare sectors, the potential applications of radiation processing of natural polymers in the medical sector are yet to be fully understood and developed. (author)

  10. Radiation Effects in the Space Telecommunications Environment

    International Nuclear Information System (INIS)

    Fleetwood, Daniel M.; Winokur, Peter S.

    1999-01-01

    Trapped protons and electrons in the Earth's radiation belts and cosmic rays present significant challenges for electronics that must operate reliably in the natural space environment. Single event effects (SEE) can lead to sudden device or system failure, and total dose effects can reduce the lifetime of a telecommmiications system with significant space assets. One of the greatest sources of uncertainty in developing radiation requirements for a space system is accounting for the small but finite probability that the system will be exposed to a massive solar particle event. Once specifications are decided, standard laboratory tests are available to predict the total dose response of MOS and bipolar components in space, but SEE testing of components can be more challenging. Prospects are discussed for device modeling and for the use of standard commercial electronics in space

  11. Radiation Effects in the Space Telecommunications Environment

    Energy Technology Data Exchange (ETDEWEB)

    Fleetwood, Daniel M.; Winokur, Peter S.

    1999-05-17

    Trapped protons and electrons in the Earth's radiation belts and cosmic rays present significant challenges for electronics that must operate reliably in the natural space environment. Single event effects (SEE) can lead to sudden device or system failure, and total dose effects can reduce the lifetime of a telecommmiications system with significant space assets. One of the greatest sources of uncertainty in developing radiation requirements for a space system is accounting for the small but finite probability that the system will be exposed to a massive solar particle event. Once specifications are decided, standard laboratory tests are available to predict the total dose response of MOS and bipolar components in space, but SEE testing of components can be more challenging. Prospects are discussed for device modeling and for the use of standard commercial electronics in space.

  12. Measuring space radiation shielding effectiveness

    Directory of Open Access Journals (Sweden)

    Bahadori Amir

    2017-01-01

    Full Text Available Passive radiation shielding is one strategy to mitigate the problem of space radiation exposure. While space vehicles are constructed largely of aluminum, polyethylene has been demonstrated to have superior shielding characteristics for both galactic cosmic rays and solar particle events due to the high hydrogen content. A method to calculate the shielding effectiveness of a material relative to reference material from Bragg peak measurements performed using energetic heavy charged particles is described. Using accelerated alpha particles at the National Aeronautics and Space Administration Space Radiation Laboratory at Brookhaven National Laboratory, the method is applied to sample tiles from the Heat Melt Compactor, which were created by melting material from a simulated astronaut waste stream, consisting of materials such as trash and unconsumed food. The shielding effectiveness calculated from measurements of the Heat Melt Compactor sample tiles is about 10% less than the shielding effectiveness of polyethylene. Shielding material produced from the astronaut waste stream in the form of Heat Melt Compactor tiles is therefore found to be an attractive solution for protection against space radiation.

  13. Measuring space radiation shielding effectiveness

    Science.gov (United States)

    Bahadori, Amir; Semones, Edward; Ewert, Michael; Broyan, James; Walker, Steven

    2017-09-01

    Passive radiation shielding is one strategy to mitigate the problem of space radiation exposure. While space vehicles are constructed largely of aluminum, polyethylene has been demonstrated to have superior shielding characteristics for both galactic cosmic rays and solar particle events due to the high hydrogen content. A method to calculate the shielding effectiveness of a material relative to reference material from Bragg peak measurements performed using energetic heavy charged particles is described. Using accelerated alpha particles at the National Aeronautics and Space Administration Space Radiation Laboratory at Brookhaven National Laboratory, the method is applied to sample tiles from the Heat Melt Compactor, which were created by melting material from a simulated astronaut waste stream, consisting of materials such as trash and unconsumed food. The shielding effectiveness calculated from measurements of the Heat Melt Compactor sample tiles is about 10% less than the shielding effectiveness of polyethylene. Shielding material produced from the astronaut waste stream in the form of Heat Melt Compactor tiles is therefore found to be an attractive solution for protection against space radiation.

  14. Radiation dosimetry onboard the International Space Station ISS

    International Nuclear Information System (INIS)

    Berger, Thomas

    2008-01-01

    Besides the effects of the microgravity environment, and the psychological and psychosocial problems encountered in confined spaces, radiation is the main health detriment for long duration human space missions. The radiation environment encountered in space differs in nature front that on earth, consisting mostly of high energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones encountered on earth for occupational radiation workers. Therefore the determination and the control of the radiation load on astronauts is a moral obligation of the space faring nations. The requirements for radiation detectors in space are very different to that on earth. Limitations in mass, power consumption and the complex nature of the space radiation environment define and limit the overall construction of radiation detectors. Radiation dosimetry onboard the International Space Station (ISS) is accomplished to one part as ''operational'' dosimetry aiming for area monitoring of the radiation environment as well as astronaut surveillance. Another part focuses on ''scientific'' dosimetry aiming for a better understanding of the radiation environment and its constitutes. Various research activities for a more detailed quantification of the radiation environment as well as its distribution in and outside the space station have been accomplished in the last years onboard the ISS. The paper will focus on the current radiation detectors onboard the ISS, their results, as well as on future planned activities. (orig.)

  15. Biology relevant to space radiation

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1997-01-01

    There are only very limited data on the health effects to humans from the two major components of the radiations in space, namely protons and heavy ions. As a result, predictions of the accompanying effects must be based either on (1) data generated through studies of experimental systems exposed on earth at rates and fluences higher than those in space, or (2) extrapolations from studies of gamma and x rays. Better information is needed about the doses, dose rates, and the energy and LET spectra of the radiations at the organ level that are anticipated to be encountered during extended space missions. In particular, there is a need for better estimates of the relationship between radiation quality and biological effects. In the case of deterministic effects, it is the threshold that is important. The possibility of the occurrence of a large solar particle event (SPE) requires that such effects be considered during extended space missions. Analyses suggest, however, that it is feasible to provide sufficient shielding so as to reduce such effects to acceptable levels, particularly if the dose rates can be limited. If these analyses prove correct, the primary biological risks will be the stochastic effects (latent cancer induction). The contribution of one large SPE to the risk of stochastic effects while undesirable will not be large in comparison to the potential total dose on a mission of long duration

  16. Natural background radiation in Jordan

    International Nuclear Information System (INIS)

    Daoud, M.N.S.

    1997-01-01

    An Airborne Gamma Ray survey has been accomplished for Jordan since 1979. A complete report has been submitted to the Natural Resources Authority along with field and processed data ''digital and analogue''. Natural radioelements concentration is not provided with this report. From the corrected count rate data for each natural radioelement, Concentrations and exposure rates at the ground level were calculated. Contoured maps, showing the exposure rates and the dose rates were created. Both maps reflect the surface geology of Jordan, where the Phosphate areas are very well delineated by high-level contours. In southeastern Jordan the Ordovician sandstone, which contain high percentage of Th (around 2000 ppm in some places) and a moderate percentage of U (about 300 ppm), also show high gamma radiation exposures compared with the surrounding areas. Comparing the values of the exposure rates given in (μR/h) to those obtained from other countries such as United States, Canada, Germany, etc. Jordan shows higher background radiation which reach two folds and even more than those in these countries. More detailed studies should be performed in order to evaluate the radiological risk limits on people who are living in areas of high radiation such that the area of the phosphatic belt which covers a vast area of Jordan high Plateau. (author)

  17. Genetic effects of natural radiation

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B.L.

    1982-01-01

    Genetic defects from mutations affect about 3% of the population. Studies of spontaneously-occurring mutations because of radiation show that the Law of Natural Selection precludes the genetic destruction of the human race. Although exposure to radiation from expanding nuclear industry could shift the occurrence of mutations a few hundredths of one percent, natural radiation causes only about 3% of all genetic effects. The Nuclear Regulatory Commission assesses the risk of an all-nuclear power society at 32 cases per year, or 0.03% above the natural incidence of genetic disease. Public concern over nuclear accidents focuses on the potential for a catastrophic accident, but the statistical genetic effects of a worst-case accident would be undetectable. Efforts to understand and deal with the genetic hazards of delayed parenthood and chemical mutagens coupled with new developments in medical intervention depend upon a continual improvement in the standard of living and the abundant supplies of cheap energy that nuclear power can help to provide. 3 footnotes. (DCK)

  18. Miniature Active Space Radiation Dosimeter, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Space Micro will extend our Phase I R&D to develop a family of miniature, active space radiation dosimeters/particle counters, with a focus on biological/manned...

  19. Natural radiation dose to Gammarus

    International Nuclear Information System (INIS)

    Paschoa, A.S.; Wrenn, M.E.; Eisenbud, M.

    1975-01-01

    The natural radiation dose rate to whole body and components of the Gammarus species (i.e., G. Tigrinus, G. Fasciatus and G. Daiberi) that occurs in the Hudson River is evaluated and the results compared with the upper limits of dose rates from man made sources to the whole body of the organisms. Methods were developed to study the distribution of alpha emitters from 226 Ra plus daughter products in Gammarus using autoradiographic techniques, taking into account the amount of radon that escapes from the organisms. This methodology may be adapted to study the distribution of alpha emitters in contaminated tissues of plants and animals

  20. Variation of Natural Gamma Radiation in Isparta

    International Nuclear Information System (INIS)

    Akkurt, I.

    2004-01-01

    There is always a radiation in the earth, and its level is generated primarily by galactic cosmic rays (GCR), consisting of energetic nuclei of all naturally occurring elements, interacting with atmospheric constituents, through atomic and nuclear collisions. The other sources of natural radiations are global average background radiation from terrestrial sources such as soils, rocks ete. Background radiation levels in the atmosphere vary in intensity with latitude, altitude and phase of the solar cycle. Variation of natural radiation as a function of altitude, geological structure etc has been investigated. The measurements were performed using portable radiation counter which connected to NaI(Tl) probe

  1. A Radiation Nose for monitoring radiation in space missions

    Data.gov (United States)

    National Aeronautics and Space Administration — This project developed a radiation monitoring system using conventional silicon CMOS (complementary metal oxide semiconductor) chip except by replacing the silicon...

  2. Passive radiation shielding considerations for the proposed space elevator

    Science.gov (United States)

    Jorgensen, A. M.; Patamia, S. E.; Gassend, B.

    2007-02-01

    The Earth's natural van Allen radiation belts present a serious hazard to space travel in general, and to travel on the space elevator in particular. The average radiation level is sufficiently high that it can cause radiation sickness, and perhaps death, for humans spending more than a brief period of time in the belts without shielding. The exact dose and the level of the related hazard depends on the type or radiation, the intensity of the radiation, the length of exposure, and on any shielding introduced. For the space elevator the radiation concern is particularly critical since it passes through the most intense regions of the radiation belts. The only humans who have ever traveled through the radiation belts have been the Apollo astronauts. They received radiation doses up to approximately 1 rem over a time interval less than an hour. A vehicle climbing the space elevator travels approximately 200 times slower than the moon rockets did, which would result in an extremely high dose up to approximately 200 rem under similar conditions, in a timespan of a few days. Technological systems on the space elevator, which spend prolonged periods of time in the radiation belts, may also be affected by the high radiation levels. In this paper we will give an overview of the radiation belts in terms relevant to space elevator studies. We will then compute the expected radiation doses, and evaluate the required level of shielding. We concentrate on passive shielding using aluminum, but also look briefly at active shielding using magnetic fields. We also look at the effect of moving the space elevator anchor point and increasing the speed of the climber. Each of these mitigation mechanisms will result in a performance decrease, cost increase, and technical complications for the space elevator.

  3. Space Radiation Intelligence System (SPRINTS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NextGen Federal Systems proposes an innovative SPace Radiation INTelligence System (SPRINTS) which provides an interactive and web-delivered capability that...

  4. Space Radiation and Manned Mission: Interface Between Physics and Biology

    Science.gov (United States)

    Hei, Tom

    2012-07-01

    The natural radiation environment in space consists of a mixed field of high energy protons, heavy ions, electrons and alpha particles. Interplanetary travel to the International Space Station and any planned establishment of satellite colonies on other solar system implies radiation exposure to the crew and is a major concern to space agencies. With shielding, the radiation exposure level in manned space missions is likely to be chronic, low dose irradiation. Traditionally, our knowledge of biological effects of cosmic radiation in deep space is almost exclusively derived from ground-based accelerator experiments with heavy ions in animal or in vitro models. Radiobiological effects of low doses of ionizing radiation are subjected to modulations by various parameters including bystander effects, adaptive response, genomic instability and genetic susceptibility of the exposed individuals. Radiation dosimetry and modeling will provide conformational input in areas where data are difficult to acquire experimentally. However, modeling is only as good as the quality of input data. This lecture will discuss the interdependent nature of physics and biology in assessing the radiobiological response to space radiation.

  5. Some characteristics and effects of natural radiation

    International Nuclear Information System (INIS)

    Mc Laughlin, J.P.

    2015-01-01

    Since life first appeared on the Earth, it has, in all its subsequent evolved forms including human, been exposed to natural radiation in the environment both from terrestrial and extra-terrestrial sources. Being an environmental mutagen, ionising natural radiation may have played a role of some significance in the evolution of early life forms on Earth. It has been estimated by United Nations Scientific Committee on the Effects of Atomic Radiation that at the present time, exposure to natural radiation globally results in an annual average individual effective dose of about 2.4 mSv. This represents about 80 % of the total dose from all sources. The three most important components of natural radiation exposure are cosmic radiation, terrestrial radioactivity and indoor radon. Each of these components exhibits both geographical and temporal variabilities with indoor radon exposure being the most variable and also the largest contributor to dose for most people. In this account, an overview is given of the characteristics of the main components of the natural radiation environment and some of their effects on humans. In the case of cosmic radiation, these range from radiation doses to aircrew and astronauts to the controversial topic of its possible effect on climate change. In the case of terrestrial natural radiation, accounts are given of a number of human exposure scenarios. (author)

  6. Ionizing radiations and dosimetry in space environment

    International Nuclear Information System (INIS)

    Doke, Tadayoshi

    1990-01-01

    Recently, plans have been developed for the construction of bases on the moon and launch of manned spacecraft to Mars. In the present report, the level of radiations in space, possible exposure of astronauts to radiations, appropriate levels of permissible exposure to such radiations, and available techniques to measure the dose equivalent are discussed in relation to long stays of astronauts in space outside the magnetosphere. Specifically, the report first outlines major features of radiations in the space environment focusing on electron and proton beams caught by the terrestrial magnitism, radiations released by the sun and galactic cosmic rays, and then presents estimations of possible exposure dose in space focusing on the contributions of electron and proton beams caught by the terrestrial magnetism, radiations released by the sun and galactic cosmic rays. The report also addresses guidelines for protection from radiations in space, techniques for measuring the intensity of radiations in space. It is pointed out that more studies should be made to permit accurate measurement of radiation doses in a mixed field containing high-energy heavy particles. (N.K.)

  7. Guidance on radiation received in space activities

    International Nuclear Information System (INIS)

    1989-01-01

    The purposes of this report, therefore, are to: re-examine the current guidelines and the philosophy adopted by NASA, estimate the risks to both men and women exposed to radiation in space, re-examine the estimates of radiation risks in outer space with special attention to SPE and to exposure to HZE particles, and examine what information may still be required and what research is needed. This report incorporates the changes in estimates of terrestrial radiation risks made since 1970 that appear to be acceptable and appropriate to the particular case of space missions. Since plans for a space station have been established and are a priority for NASA, this space mission will be used as one example for reference. The likely altitude and orbit for the proposed space station are 450 km and 28.5 degree, respectively. Therefore, estimates of the radiation environment for this mission can be made with more confidence than for some of the other missions. In this report, we have chosen to write more fully about certain subjects, for example, the eye, because they are of concern and because they have not been dealt with in such detail in other reports on radiation risks and protection. Since this report covers a number of different disciplines and specialized areas of research, a glossary is included. Radiation protection in space is as international a task as is the protection of radiation workers and the general population on earth. Kovalev, 1983, has noted that radiation protection in space is a pressing but complex problem. The recommendations in this report will require modifications as we learn more about the radiation environment in space and how to estimate radiation risks with greater precision. 450 refs

  8. Space radiation and cataracts in astronauts

    Science.gov (United States)

    Cucinotta, F. A.; Manuel, F. K.; Jones, J.; Iszard, G.; Murrey, J.; Djojonegro, B.; Wear, M.

    2001-01-01

    For over 30 years, astronauts in Earth orbit or on missions to the moon have been exposed to space radiation comprised of high-energy protons and heavy ions and secondary particles produced in collisions with spacecraft and tissue. Large uncertainties exist in the projection of risks of late effects from space radiation such as cancer and cataracts due to the paucity [corrected] of epidemiological data. Here we present epidemiological [corrected] data linking an increased risk of cataracts for astronauts with higher lens doses (>8 mSv) of space radiation relative to other astronauts with lower lens doses (astronauts participating in NASA's Longitudinal Study of Astronaut Health (LSAH) and individual occupational radiation exposure data. These results, while preliminary because of the use of subjective scoring methods, suggest that relatively low doses of space radiation may predispose crew to [corrected] an increased incidence and early appearance of cataracts.

  9. Natural radiation, nuclear wastes and chemical pollutants

    International Nuclear Information System (INIS)

    Christensen, T.; Ehdwall, H.; Stranden, E.

    1990-01-01

    Doses from natural radiation to the population in the Nordic Countries are summarized and man made modifications of the natural radiation environment are discussed. An account is given of the radiological consequences of energy conservation by reduced ventilation. Risks from possible future releases of radioactivity from final repositories of spent nuclear fuel are compared to the risks from present natural radioactivity in the environment. The possibilities for comparison between chemical and radiological risks are discussed. (author) 13 refs

  10. The NASA Space Radiation Research Program

    Science.gov (United States)

    Cucinotta, Francis A.

    2006-01-01

    We present a comprehensive overview of the NASA Space Radiation Research Program. This program combines basic research on the mechanisms of radiobiological action relevant for improving knowledge of the risks of cancer, central nervous system and other possible degenerative tissue effects, and acute radiation syndromes from space radiation. The keystones of the NASA Program are five NASA Specialized Center's of Research (NSCOR) investigating space radiation risks. Other research is carried out through peer-reviewed individual investigations and in collaboration with the US Department of Energies Low-Dose Research Program. The Space Radiation Research Program has established the Risk Assessment Project to integrate data from the NSCOR s and other peer-reviewed research into quantitative projection models with the goals of steering research into data and scientific breakthroughs that will reduce the uncertainties in current risk projections and developing the scientific knowledge needed for future individual risk assessment approaches and biological countermeasure assessments or design. The NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory was created by the Program to simulate space radiation on the ground in support of the above research programs. New results from NSRL will be described.

  11. Space storms as natural hazards

    Directory of Open Access Journals (Sweden)

    L. I. Dorman

    2008-04-01

    Full Text Available Eruptive activity of the Sun produces a chain of extreme geophysical events: high-speed solar wind, magnetic field disturbances in the interplanetary space and in the geomagnetic field and also intense fluxes of energetic particles. Space storms can potentially destroy spacecrafts, adversely affect astronauts and airline crew and human health on the Earth, lead to pipeline breaking, melt electricity transformers, and discontinue transmission. In this paper we deal with two consequences of space storms: (i rise in failures in the operation of railway devices and (ii rise in myocardial infarction and stroke incidences.

  12. Radiation processing of natural polymer in Malaysia

    International Nuclear Information System (INIS)

    Khairul Zaman; Kamaruddin Hashim; Zulkafli Ghazali; Mohd Hilmi Mahmood; Dahlan Hj. Mohd; Jamaliah Sharif

    2007-01-01

    Research on radiation processing of natural polymer has been carried out by Nuclear Malaysia since 10 years ago. The progress of the research is at various stages. Radiation processing of sago hydrogel has been commercialized. Meanwhile ago film for packaging is at the pilot scale trial. Palm oil products are ready to be further developed for commercialization with any interested industrial partner. On the other hand, some new materials are being developed based on natural rubber such as liquid natural as compatibilizer, natural rubber thermoplastic nanoclay composites and natural rubber magnetic nano particles composites. (author)

  13. Deep space test bed for radiation studies

    International Nuclear Information System (INIS)

    The Deep Space Test-Bed (DSTB) Facility is designed to investigate the effects of galactic cosmic rays on crews and systems during missions to the Moon or Mars. To gain access to the interplanetary ionizing radiation environment the DSTB uses high-altitude polar balloon flights. The DSTB provides a platform for measurements to validate the radiation transport codes that are used by NASA to calculate the radiation environment within crewed space systems. It is also designed to support other exploration related investigations such as measuring the shielding effectiveness of candidate spacecraft and habitat materials, testing new radiation monitoring instrumentation, flight avionics and investigating the biological effects of deep space radiation. We describe the work completed thus far in the development of the DSTB and its current status

  14. Radiation Hardness Assurance for Space Systems

    Science.gov (United States)

    Poivey, Christian; Day, John H. (Technical Monitor)

    2002-01-01

    The space radiation environment can lead to extremely harsh operating conditions for on-board electronic box and systems. The characteristics of the radiation environment are highly dependent on the type of mission (date, duration and orbit). Radiation accelerates the aging of the electronic parts and material and can lead to a degradation of electrical performance; it can also create transient phenomena on parts. Such damage at the part level can induce damage or functional failure at electronic box, subsystem, and system levels. A rigorous methodology is needed to ensure that the radiation environment does not compromise the functionality and performance of the electronics during the system life. This methodology is called hardness assurance. It consists of those activities undertaken to ensure that the electronic piece parts placed in the space system perform to their design specifications after exposure to the space environment. It deals with system requirements, environmental definitions, part selection, part testing, shielding and radiation tolerant design. All these elements should play together in order to produce a system tolerant to.the radiation environment. An overview of the different steps of a space system hardness assurance program is given in section 2. In order to define the mission radiation specifications and compare these requirements to radiation test data, a detailed knowledge of the space environment and the corresponding electronic device failure mechanisms is required. The presentation by J. Mazur deals with the Earth space radiation environment as well as the internal environment of a spacecraft. The presentation by J. Schwank deals with ionization effects, and the presentation by T. Weatherford deals with Single particle Event Phenomena (SEP) in semiconductor devices and microcircuits. These three presentations provide more detailed background to complement the sections 3 and 4. Part selection and categorization are discussed in section

  15. Natural radiation environment III. [Lead Abstract

    Energy Technology Data Exchange (ETDEWEB)

    Gesell, T.F.; Lowder, W.M. (eds.)

    1980-01-01

    Separate abstracts were prepared for the 52 research papers presented at this symposium in April 1978. The major topics in this volume deal with penetrating radiation measurements, radiation surveys and population exposure, radioactivity in the indoor environment, and technologically enhanced natural radioactivity. (KRM)

  16. 2014 Space Radiation Standing Review Panel

    Science.gov (United States)

    Steinberg, Susan

    2015-01-01

    The 2014 Space Radiation Standing Review Panel (from here on referred to as the SRP) participated in a WebEx/teleconference with members of the Space Radiation Program Element, representatives from the Human Research Program (HRP), the National Space Biomedical Research Institute (NSBRI), and NASA Headquarters on November 21, 2014 (list of participants is in Section XI of this report). The SRP reviewed the updated Research Plan for the Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure (Degen Risk). The SRP also received a status update on the Risk of Acute and Late Central Nervous System Effects from Radiation Exposure (CNS Risk), the Risk of Acute Radiation Syndromes Due to Solar Particle Events (ARS Risk), and the Risk of Radiation Carcinogenesis (Cancer Risk). The SRP thought the teleconference was very informative and that the Space Radiation Program Element did a great job of outlining where the Element is with respect to our state of knowledge on the risks of carcinogenesis, central nervous system effects, and the risk of cardiovascular disease and other degenerative tissue effects from exposure to space radiation. The SRP was impressed with the quality of research that is being conducted and the progress the Space Radiation Program Element has made in the past year. While much work has been done, the SRP had a few remaining questions regarding the broad applicability of these findings to a manned deep space mission (in terms of cognitive function, the paradigms were still hippocampal based and also using Alzheimer disease models). The SRP believes that NASA should consider developing an approach to follow astronauts long-term (beyond retirement) for potential side-effects/risks of space exposure that may be unknown. Radiation toxicities often occur decades after exposure, and potential consequences would be missed if intensified exams stop after retirement of the astronauts. In addition, while cancer is one

  17. Radiation protection guidelines for space missions

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1987-01-01

    The original recommendations for radiation protection guidelines were made by the National Academy of Sciences in 1970. Since that time the US crews have become more diverse in their makeup and much has been learned about both radiation-induced cancer and other late effects. While far from adequate there is now some understanding of the risks that high-Z and -energy (HZE) particles pose. For these reasons it was time to reconsider the radiation protection guidelines for space workers. This task was undertaken recently by National Council on Radiation Protection (NCRP). 42 refs., 2 figs., 9 tabs

  18. Biosentinel: Developing a Space Radiation Biosensor

    Science.gov (United States)

    Santa Maria, Sergio R.; Marina, Diana B.; Parra, Macarena P.; Boone, Travis D.; Tan, Ming; Ricco, Antonio J.; Straume, Tore N.; Lusby, Terry C.; Harkness, T.; Reiss-Bubenheim, Debra; hide

    2014-01-01

    Ionizing radiation presents a major challenge to human exploration and long-term residence in space. The deep-space radiation spectrum includes highly energetic particles that generate double strand breaks (DSBs), deleterious DNA lesions that are usually repaired without errors via homologous recombination (HR), a conserved pathway in all eukaryotes. While progress identifying and characterizing biological radiation effects using Earth-based facilities has been significant, no terrestrial source duplicates the unique space radiation environment.We are developing a biosensor-based nanosatellite to fly aboard NASAs Space Launch System Exploration Mission 1, expected to launch in 2017 and reach a 1AU (astronomic unit) heliocentric orbit. Our biosensor (called BioSentinel) uses the yeast S. cerevisiae to measure DSBs in response to ambient space radiation. The BioSentinel strain contains engineered genetic defects that prevent growth until and unless a radiation-induced DSB near a reporter gene activates the yeasts HR repair mechanisms. Thus, culture growth and metabolic activity directly indicate a successful DSB-and-repair event. In parallel, HR-defective and wild type strains will provide survival data. Desiccated cells will be carried within independent culture microwells, built into 96-well microfluidic cards. Each microwell set will be activated by media addition at different time points over 18 months, and cell growth will be tracked continuously via optical density. One reserve set will be activated only in the occurrence of a solar particle event. Biological measurements will be compared to data provided by onboard physical dosimeters and to Earth-based experiments.BioSentinel will conduct the first study of biological response to space radiation outside Low Earth Orbit in over 40 years. BioSentinel will thus address strategic knowledge gaps related to the biological effects of space radiation and will provide an adaptable platform to perform human

  19. Controllable forms of natural background radiation

    International Nuclear Information System (INIS)

    1988-03-01

    RENA is a research programm into the controllable forms of natural background radiation, which cover the activities originating from the naturally occurring radionuclides enhanced by human intervention. In the RENA-program emphasis lays upon the policy aspects of environmental-hygienic, economical and governmental character. (H.W.). 15 refs.; 2 tabs

  20. Radiation Effects on Emerging Technologies: Implications of Space Weather Risk Management

    Science.gov (United States)

    LaBel, Kenneth A.; Barth, Janet L.

    2000-01-01

    As NASA and its space partners endeavor to develop a network of satellites capable of supporting humankind's needs for advanced space weather prediction and understanding, one of the key challenges is to design a space system to operate in the natural space radiation environment In this paper, we present a description of the natural space radiation environment, the effects of interest to electronic or photonic systems, and a sample of emerging technologies and their specific issues. We conclude with a discussion of operations in the space radiation hazard and considerations for risk management.

  1. Detection of DNA damage by space radiation in human fibroblasts flown on the International Space Station

    Science.gov (United States)

    Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

    2017-02-01

    Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation. In this study, cultured human fibroblasts were flown on the International Space Station (ISS). Cells were kept at 37 °C in space for 14 days before being fixed for analysis of DNA damage with the γ-H2AX assay. The 3-dimensional γ-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed several foci that were larger and displayed a track pattern only in the Day 14 flight samples. To confirm that the foci data from the flight study was actually induced from space radiation exposure, cultured human fibroblasts were exposed to low dose rate γ rays at 37 °C. Cells exposed to chronic γ rays showed similar foci size distribution in comparison to the non-exposed controls. The cells were also exposed to low- and high-LET protons, and high-LET Fe ions on the ground. Our results suggest that in G1 human fibroblasts under the normal culture condition, only a small fraction of large size foci can be attributed to high-LET radiation in space.

  2. Natural radiation load in the FRG

    International Nuclear Information System (INIS)

    Bonka, H.

    1974-01-01

    The distribution of the mean natural radiation exposure in the FRG is of the utmost importance for the assessment of the additional population exposure to radionuclides emitted by nuclear facilities. Maps on the cosmic, terrestric, and total natural radiation exposure in the FRG were established on the basis of data on the height dependence of the cosmic radiation exposure and measurements of the terrestric radiation exposure in the FRG published in 1960 by the Niedersaechsisches Landesamt fuer Bodenforschung. These maps are based on an assumed average person spending 80% of the day in buildings and 20% outdoors. A calibration error was found in the measurements of the terrestric radiation exposure by the Niedersaechsisches Landesamt fuer Bodenforschung. After correction, the measured values now agree with the data published by other research groups. The mean cosmic population exposure should be about 33 mrem/a, the mean terrestrial radiation exposure between 50 and 55 mrem/a, and the total natural radiation exposure about 105 mrem/a. (orig./AK) [de

  3. Natural radiation exposure modified by human activities

    International Nuclear Information System (INIS)

    Fujimoto, Kenzo

    1995-01-01

    We are now living in the radiation environment modified by our technology. It is usually called 'Technologically Enhanced Natural Radiation' and have been discussed in the UNSCEAR Reports as an important source of exposure. The terrestrial radionuclide concentrations as well as the intensity of cosmic rays are considered to have been constant after our ancestors came down from trees and started walking on their two feet. However, we have been changing our environment to be more comfortable for our life and consequently ambient radiation levels are nomore what used to be. In this paper exposures due to natural radiation modified by our following activities are discussed: housing, balneology, cave excursion, mountain climbing, skiing, swimming, smoking and usage of mineral water, well water, coal, natural gas, phosphate rocks and minerals. In the ICRP Publication No. 39, it is clearly mentioned that even natural radiation should be controlled as far as it is controllable. We have to pay more attention to our activities not to enhance the exposure due to unnecessary, avoidable radiation. (author)

  4. Space radiation risks to the central nervous system

    Science.gov (United States)

    Cucinotta, Francis A.; Alp, Murat; Sulzman, Frank M.; Wang, Minli

    2014-07-01

    Central nervous system (CNS) risks which include during space missions and lifetime risks due to space radiation exposure are of concern for long-term exploration missions to Mars or other destinations. Possible CNS risks during a mission are altered cognitive function, including detriments in short-term memory, reduced motor function, and behavioral changes, which may affect performance and human health. The late CNS risks are possible neurological disorders such as premature aging, and Alzheimer's disease (AD) or other dementia. Radiation safety requirements are intended to prevent all clinically significant acute risks. However the definition of clinically significant CNS risks and their dependences on dose, dose-rate and radiation quality is poorly understood at this time. For late CNS effects such as increased risk of AD, the occurrence of the disease is fatal with mean time from diagnosis of early stage AD to death about 8 years. Therefore if AD risk or other late CNS risks from space radiation occur at mission relevant doses, they would naturally be included in the overall acceptable risk of exposure induced death (REID) probability for space missions. Important progress has been made in understanding CNS risks due to space radiation exposure, however in general the doses used in experimental studies have been much higher than the annual galactic cosmic ray (GCR) dose (∼0.1 Gy/y at solar maximum and ∼0.2 Gy/y at solar minimum with less than 50% from HZE particles). In this report we summarize recent space radiobiology studies of CNS effects from particle accelerators simulating space radiation using experimental models, and make a critical assessment of their relevance relative to doses and dose-rates to be incurred on a Mars mission. Prospects for understanding dose, dose-rate and radiation quality dependencies of CNS effects and extrapolation to human risk assessments are described.

  5. Uniform color spaces and natural image statistics.

    Science.gov (United States)

    McDermott, Kyle C; Webster, Michael A

    2012-02-01

    Many aspects of visual coding have been successfully predicted by starting from the statistics of natural scenes and then asking how the stimulus could be efficiently represented. We started from the representation of color characterized by uniform color spaces, and then asked what type of color environment they implied. These spaces are designed to represent equal perceptual differences in color discrimination or appearance by equal distances in the space. The relative sensitivity to different axes within the space might therefore reflect the gamut of colors in natural scenes. To examine this, we projected perceptually uniform distributions within the Munsell, CIE L(*)u(*)v(*) or CIE L(*)a(*)b(*) spaces into cone-opponent space. All were elongated along a bluish-yellowish axis reflecting covarying signals along the L-M and S-(L+M) cardinal axes, a pattern typical (though not identical) to many natural environments. In turn, color distributions from environments were more uniform when projected into the CIE L(*)a(*)b(*) perceptual space than when represented in a normalized cone-opponent space. These analyses suggest the bluish-yellowish bias in environmental colors might be an important factor shaping chromatic sensitivity, and also suggest that perceptually uniform color metrics could be derived from natural scene statistics and potentially tailored to specific environments. © 2012 Optical Society of America

  6. Project Marna Natural Gamma Radiation MAP

    International Nuclear Information System (INIS)

    Suarez, E.; Fernandez, J.A.

    1997-01-01

    The confusion created by the accident that occurred in one of the Chernobyl reactors in April of 1986 made the general public and governments aware of the need for improved monitoring of environmental radiation levels. The levels of total gamma radiation or total gamma exposure rate over large areas reached values as high as 400 micro Roentgen/hour (mu R/h) and at points exceeded 1000 mu R/h. It should be borne in mind that, depending on the type of geological formations, normal values range from 5 to 30 mu R/h. The IAEA recommended to all countries that natural gamma radiation maps be made available to evaluate the levels of natural gamma radiation and possible increases, and it also indicated its concern that information be standardized. In addition, it stressed the advisability of using data obtained from uranium prospecting. (Author)

  7. Natural sources of ionizing radiation in Europe

    International Nuclear Information System (INIS)

    Green, B.M.R.; Hughes, J.S.; Lomas, P.R.

    1993-01-01

    This publication maps levels of radiation of natural origin throughout the European Community (except in the Lander of the former German Democratic Republic), in Scandinavia and in Austria. The booklet explains in simple terms the basic properties and origin of different types of radiation (cosmic rays, gamma rays and radon) and their contribution to the overall exposure of the population. A glossary, a list of administrative regions used in the maps and detailed references to the data for each country are included

  8. Space radiation health research, 1991-1992

    Science.gov (United States)

    Jablin, M. H. (Compiler); Brooks, C. (Compiler); Ferraro, G. (Compiler); Dickson, K. J. (Compiler); Powers, J. V. (Compiler); Wallace-Robinson, J. (Compiler); Zafren, B. (Compiler)

    1993-01-01

    The present volume is a collection of 227 abstracts of radiation research sponsored by the NASA Space Radiation Health Program for the period 1991-1992. Each abstract has been categorized within one of three discipline areas: Physics, Biology and Risk Assessment. Topic areas within each discipline have been assigned as follows: Physics - Atomic Physics, Theory, Cosmic Ray and Astrophysics, Experimental, Environments and Environmental Models, Solar Activity and Prediction, Experiments, Radiation Transport and Shielding, Theory and Model Development, Experimental Studies, and Instrumentation. Biology - Biology, Molecular Biology, Cellular Radiation Biology, Transformation, Mutation, Lethality, Survival, DNA Damage and Repair, Tissue, Organs, and Organisms, In Vivo/In Vitro Systems, Carcinogenesis and Life Shortening, Cataractogenesis, Genetics/Developmental, Radioprotectants, Plants, and Other Effects. Risk Assessment - Risk Assessment, Radiation Health and Epidemiology, Space Flight Radiation Health Physics, Inter- and Intraspecies Extrapolation and Radiation Limits and Standards. Section I contains refereed journals; Section II contains reports/meetings. Keywords and author indices are provided. A collection of abstracts spanning the period 1986-1990 was previously issued as NASA Technical Memorandum 4270.

  9. Synergistic effects of microgravity and space radiation (Nimblegen)

    Data.gov (United States)

    National Aeronautics and Space Administration — Space radiations and microgravity both could cause DNA damage in cells but the effects of microgravity on DNA damage response to space radiations are still...

  10. Occupational exposure to natural sources of radiation

    International Nuclear Information System (INIS)

    Ortiz, T.; Sciocchetti, G.; Rannou, A.

    1993-01-01

    The most important natural sources of radiation are analyzed. The situation in France, Italy, and Spain concerning protection against natural radiation is described, including the identification of sources, and defined practices, organizations charged of national surveys and the responsibility of regulatory bodies and the role of operating management. The activities of the international organizations (ICRP, CEC and IAEA) are presented and discussed, and existing actions toward harmonization in the CEC, IAEA and other international programs is also discussed. (R.P.) 23 refs., 2 tabs

  11. Space Radiation Program Element Tissue Sharing Forum

    Science.gov (United States)

    Wu, H.; Mayeaux, B M.; Huff, J. L.; Simonsen, L. C.

    2016-01-01

    Over the years, a large number of animal experiments have been conducted at the NASA Space Radiation Laboratory and other facilities under the support of the NASA Space Radiation Program Element (SRPE). Studies using rodents and other animal species to address the space radiation risks will remain a significant portion of the research portfolio of the Element. In order to maximize scientific return of the animal studies, the SRPE has recently released the Space Radiation Tissue Sharing Forum. The Forum provides access to an inventory of investigator-stored tissue samples and enables both NASA SRPE members and NASA-funded investigators to exchange information regarding stored and future radiobiological tissues available for sharing. Registered users may review online data of available tissues, inquire about tissues posted, or request tissues for an upcoming study using an online form. Investigators who have upcoming sacrifices are also encouraged to post the availability of samples using the discussion forum. A brief demo of the forum will be given during the presentation

  12. Conceptual designs for 100-MW space radiators

    International Nuclear Information System (INIS)

    Prenger, F.C.; Sullivan, J.A.

    1982-01-01

    A description and comparison of heat rejection systems for multimegawatt space-based power supplies is given. Current concepts are described, and through a common performance parameter, these are compared with three advanced radiator concepts. The comparison is based on a power system that rejects 100 MW of heat while generating 10 MW of electrical power

  13. Radiation protection guidelines for space missions

    International Nuclear Information System (INIS)

    Fry, R.J.; Nachtwey, D.S.

    1988-01-01

    The current radiation protection guidelines of the National Aeronautics and Space Administration (NASA) were recommended in 1970. The career limit was set at 4.0 Sv (400 rem). Using the same approach as in 1970 but current risk estimates, a considerably lower career limit would obtain today. Also, there is now much more information about the radiation environments that will be experienced in different missions. Furthermore, since 1970 women have joined the ranks of the astronauts. For these and other reasons, it was considered necessary to re-examine the radiation protection guidelines. This task has been undertaken by the National Council on Radiation Protection and Measurements Scientific Committee 75. Within the magnetosphere, the radiation environment varies with altitude and inclination of the orbit. In outer space missions, galactic cosmic rays, with the small but important heavy-ion component, determine the radiation environment. The new recommendations for career dose limits, based on lifetime excess risk of cancer mortality, take into account age at first exposure and sex. The career limits range from 1.0 Sv (100 rem) for a 24-y-old female up to 4.0 Sv (400 rem) for a 55-y-old male, compared with the previous single limit of 4.0 Sv (400 rem). The career limit for the lens of the eye has been reduced from 6.0 Sv (600 rem) to 4.0 Sv (400 rem)

  14. Radiation Risk Projections for Space Travel

    Science.gov (United States)

    Cucinotta, Francis

    2003-01-01

    Space travelers are exposed to solar and galactic cosmic rays comprised of protons and heavy ions moving with velocities close to the speed of light. Cosmic ray heavy ions are known to produce more severe types of biomolecular damage in comparison to terrestrial forms of radiation, however the relationship between such damage and disease has not been fully elucidated. On Earth, we are protected from cosmic rays by atmospheric and magnetic shielding, and only the remnants of cosmic rays in the form of ground level muons and other secondary radiations are present. Because human epidemiology data is lacking for cosmic rays, risk projection must rely on theoretical understanding and data from experimental models exposed to space radiation using charged particle accelerators to simulate space radiation. Although the risks of cancer and other late effects from cosmic rays are currently believed to present a severe challenge to space travel, this challenge is centered on our lack of confidence in risk projections methodologies. We review biophysics and radiobiology data on the effects of the cosmic ray heavy ions, and the current methods used to project radiation risks . Cancer risk projections are described as a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. Risk projections for space travel are described using Monte-Carlo sampling from subjective error di stributions that represent the lack of knowledge in each factor that contributes to the projection model in order to quantify the overall uncertainty in risk projections. This analysis is applied to space mi ssion scenarios including lunar colony, deep space outpost, and a Mars mission. Results suggest that the number of days in space where cancer mortality risks can be assured at a 95% confidence level to be below the maximum acceptable risk for radi ation workers on Earth or the International Space Station is only on the order

  15. Exposures to natural radiation in Switzerland

    International Nuclear Information System (INIS)

    Murith, Ch.; Gurtner, A.

    1999-01-01

    The exposure of human beings to ionising radiation from natural sources is a continuing and inescapable feature of life on earth. There are two main sources that contribute to this exposure: high-energy cosmic-ray particles incident to the earth's atmosphere and radioactive nuclides that originated in the earth's crust and are present everywhere in the environment, including human body itself. Both external and internal exposures to humans arise from these sources. Exposures to natural radiation sources in Switzerland and some of their variations are here summarised and the resulting effective doses are compared to those from man-made sources exposures. It results that the natural background exposures are more significant for the population than most exposures to man-made sources. (authors)

  16. 2015 Space Radiation Standing Review Panel

    Science.gov (United States)

    Steinberg, Susan

    2015-01-01

    The 2015 Space Radiation Standing Review Panel (from here on referred to as the SRP) met for a site visit in Houston, TX on December 8 - 9, 2015. The SRP met with representatives from the Space Radiation Element and members of the Human Research Program (HRP) to review the updated research plan for the Risk of Radiation Carcinogenesis Cancer Risk. The SRP also reviewed the newly revised Evidence Reports for the Risk of Acute Radiation Syndromes Due to Solar Particle Events (SPEs) (Acute Risk), the Risk of Acute (In-flight) and Late Central Nervous System Effects from Radiation Exposure (CNS Risk), and the Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation (Degen Risk), as well as a status update on these Risks. The SRP would like to commend Dr. Simonsen, Dr. Huff, Dr. Nelson, and Dr. Patel for their detailed presentations. The Space Radiation Element did a great job presenting a very large volume of material. The SRP considers it to be a strong program that is well-organized, well-coordinated and generates valuable data. The SRP commended the tissue sharing protocols, working groups, systems biology analysis, and standardization of models. In several of the discussed areas the SRP suggested improvements of the research plans in the future. These include the following: It is important that the team has expanded efforts examining immunology and inflammation as important components of the space radiation biological response. This is an overarching and important focus that is likely to apply to all aspects of the program including acute, CVD, CNS, cancer and others. Given that the area of immunology/inflammation is highly complex (and especially so as it relates to radiation), it warrants the expansion of investigators expertise in immunology and inflammation to work with the individual research projects and also the NASA Specialized Center of Research (NSCORs). Historical data on radiation injury to be entered into the Watson

  17. Laser-plasma-based Space Radiation Reproduction in the Laboratory.

    Science.gov (United States)

    Hidding, B; Karger, O; Königstein, T; Pretzler, G; Manahan, G G; McKenna, P; Gray, R; Wilson, R; Wiggins, S M; Welsh, G H; Beaton, A; Delinikolas, P; Jaroszynski, D A; Rosenzweig, J B; Karmakar, A; Ferlet-Cavrois, V; Costantino, A; Muschitiello, M; Daly, E

    2017-02-08

    Space radiation is a great danger to electronics and astronauts onboard space vessels. The spectral flux of space electrons, protons and ions for example in the radiation belts is inherently broadband, but this is a feature hard to mimic with conventional radiation sources. Using laser-plasma-accelerators, we reproduced relativistic, broadband radiation belt flux in the laboratory, and used this man-made space radiation to test the radiation hardness of space electronics. Such close mimicking of space radiation in the lab builds on the inherent ability of laser-plasma-accelerators to directly produce broadband Maxwellian-type particle flux, akin to conditions in space. In combination with the established sources, utilisation of the growing number of ever more potent laser-plasma-accelerator facilities worldwide as complementary space radiation sources can help alleviate the shortage of available beamtime and may allow for development of advanced test procedures, paving the way towards higher reliability of space missions.

  18. Time-dependent radiation dose estimations during interplanetary space flights

    Science.gov (United States)

    Dobynde, M. I.; Shprits, Y.; Drozdov, A.

    2015-12-01

    Time-dependent radiation dose estimations during interplanetary space flights 1,2Dobynde M.I., 2,3Drozdov A.Y., 2,4Shprits Y.Y.1Skolkovo institute of science and technology, Moscow, Russia 2University of California Los Angeles, Los Angeles, USA 3Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics, Moscow, Russia4Massachusetts Institute of Technology, Cambridge, USASpace radiation is the main restriction for long-term interplanetary space missions. It induces degradation of external components and propagates inside providing damage to internal environment. Space radiation particles and induced secondary particle showers can lead to variety of damage to astronauts in short- and long- term perspective. Contribution of two main sources of space radiation- Sun and out-of-heliosphere space varies in time in opposite phase due to the solar activity state. Currently the only habituated mission is the international interplanetary station that flights on the low Earth orbit. Besides station shell astronauts are protected with the Earth magnetosphere- a natural shield that prevents significant damage for all humanity. Current progress in space exploration tends to lead humanity out of magnetosphere bounds. With the current study we make estimations of spacecraft parameters and astronauts damage for long-term interplanetary flights. Applying time dependent model of GCR spectra and data on SEP spectra we show the time dependence of the radiation in a human phantom inside the shielding capsule. We pay attention to the shielding capsule design, looking for an optimal geometry parameters and materials. Different types of particles affect differently on the human providing more or less harm to the tissues. Incident particles provide a large amount of secondary particles while propagating through the shielding capsule. We make an attempt to find an optimal combination of shielding capsule parameters, namely material and thickness, that will effectively decrease

  19. Proceedings of the 8. International symposium on the natural radiation environment (NRE-VIII). Book of abstracts

    International Nuclear Information System (INIS)

    2007-01-01

    Theoretical and experimental papers are presented in these proceedings covering the following subjects: cosmic radiation, solar activity and cosmogenic radionuclides - natural radiation from space, high background areas - life in naturally elevated radiation areas, radon and thoron - indoors and outdoors, other terrestrial natural radionuclides - natural radioactivity, NORM/TENORM, including depleted uranium - technologically enhanced natural radioactivity, dosimetry and health risk assessment biological effects of natural radioactivity , exposures of biota to natural radioactivity, metrology, modelling and epidemiology, BSS and legal issues - regulating natural radioactivity, RDD (dirty bombs and terrorism - terrorism and natural radioactive material, non-ionising radiation (NIR) an the NRE 11), geochronology plus natural radioactivity and the theory of time

  20. Radiation response of Philippine natural rubber latex

    International Nuclear Information System (INIS)

    Dela Rosa, A.M.; Abad, L.V.; Ana-Relleve, L.S.; Tranquilan-Aranilla, C.; Pascual, C.L.

    1998-01-01

    Our earlier work has shown that the natural rubber latex (NRL) produced and processed in the Philippines is suited for radiation vulcanization. The cast films from NRL with 50% TSC exhibited maximum tensile strengths of 25-32 MPa at 15 kGy, which is the vulcanization dose or Dv. In the manufacture of dipped NRL products, certain specifications such as %TSC, protein content and tensile properties, must be met to ensure an acceptable product. For radiation vulcanization of natural rubber latex (RVNRL) to be accepted as an alternative process, it must also meet the requirements. Thus, this paper presents additional data on the radiation response of local NRL at different total solids contents (TSC), leachable proteins from NRL films as a function of dose, and the thermal activities of irradiated natural rubber latex (INRL). Different formulations of NRL showed varying tolerances to nBA. Data showed that as %TSC increases, the maximum concentration of nBA that can be added without affecting the stability of the latex decreases. The Dv increases as the %TSC increases and the nBA content decreases. This difference in response may be attributed to a lower concentration of nBA in formulations with higher %TSC. These data indicate that the parameters in the radiation treatment will be dictated by the intended applications of INRL. The thermogravimetric data showed greater stability of INRL to thermal oxidation relative to the unirradiated NRL, which correlates directly with the tensile properties of the INRL. A radiation dose of 10 kGy increased the amount of proteins leached from cast latex films. The amount of extractable proteins did not increase significantly at higher doses. The SDS PAGE analysis of the extractable proteins from unirradiated latex film showed distinct bands. An additional band at 60 Kda appeared at 10 kGy. All these bands became diffuse at higher doses, indicating the radiolysis of the proteins

  1. Space Radiation Research Unit, International Open Laboratory in NIRS

    OpenAIRE

    Uchihori, Yukio; Hei, Tom K.; Konishi, Teruaki; Kobayashi, Alisa; Kitamura, Hisashi; Kodaira, Satoshi; Kobayashi, Shingo

    2014-01-01

    The radiation environment encountered by astronauts during spaceflight is far more complex than any radiation field existed on Earth. Space crew living and working in the International Space Station (ISS) are exposed to a mixed radiation field comprises primary high-energy cosmic rays, including energetic protons and heavy ions, and to secondary radiations, including energetic neutrons, produced when the primary radiation interacts with the mass of the space station and its contents. The dose...

  2. Ore sorting using natural gamma radiation

    International Nuclear Information System (INIS)

    Clark, G.J.; Dickson, B.L.; Gray, F.E.

    1980-01-01

    A method of sorting an ore which emits natural gamma radiation is described, comprising the steps of: (a) mining the ore, (b) placing, substantially at the mining location, the sampled or mined ore on to a moving conveyor belt, (c) measuring the natural gamma emission, water content and mass of the ore while the ore is on the conveyor belt, (d) using the gamma, water content and mass measurements to determine the ore grade, and (e) directing the ore to a location characteristic of its grade when it leaves the conveyor belt

  3. A selected bibliography on natural radiation, 1

    International Nuclear Information System (INIS)

    Abe, Siro; Abe, Michiko; Fujitaka, Kazunobu; Fujimoto, Kenzo.

    1977-03-01

    Natural radioactive substances in the environment are important in general scientific research and impacts on human beings. The natural levels of radiations are then involved in peaceful uses of nuclear energy. The present bibliography is intended to meet the needs in this field. Entries complete with an abstract are selected from Nuclear Science Abstracts of vol. 1 (1948) to vol. 32 (December 1975). Only the primordial radionuclides as follows, without series, are treated concerning the levels, measurements, etc. : 40 K, 50 V, 87 Rb, 115 In, 123 Te, 138 La, 142 Ce, 144 Nd, 147 Sm, 152 Gd, 176 Lu, 174 Hf, 187 Re, and 190 Pt. (Mori, K.)

  4. The Nature of Space and Time

    International Nuclear Information System (INIS)

    Wijland, Frederic van

    1997-01-01

    The Nature of Space and Time is a seven and a half hour long video that comes in a three tape set. Professors Hawking and Penrose are shown giving a series of one hour lectures at the Isaac Newton Institute. The topics of their talks range from the structure of space-time to the quantum theory of gravitation. They are organized along three main lines. Both speakers first discuss the singularities of space and time within the framework of classical general relativity, that is, as deduced from Einstein's equations. After giving arguments in favour of the existence of closed trapped surfaces (collapsing stars, black holes), Hawking draws a parallel between thermodynamic irreversibility and the loss of information coming from gravity trapped surfaces. Instead, Penrose insists on the mathematical structure of the singularities, using in particular the Weyl curvature to characterize them. From his analysis two classes of singularities emerge: those from which matter comes out (big bang) and those in which matter comes in (big crunch, black holes). The classical setting being recalled, the speakers turn to quantum theory. Hawking's second talk is concerned with the quantum theory of black holes. In order to account for quantum effects, he introduces a path-integral formulation over Euclideanized metrics, Armed with this tool, the validity of which he merely assumes, he proves that black holes actually radiate so that he renders fully consistent the thermodynamic analogy, entropy being replaced by the area event horizon, and statistical fluctuations by quantum fluctuations. Basing his analysis upon an interpretation in terms of information theory, there exists, Hawking asserts, a new level of unpredictability. Penrose prefers not to expand on Hawking's interpretations and starts building upon quantum mechanics (analysis of the EPR experiment) and the density matrix formalism to stress the problems caused by the nonlocality of energy. In his last lecture Hawking comes back

  5. The Nature of Space and Time

    Energy Technology Data Exchange (ETDEWEB)

    Wijland, Frederic van

    1997-09-01

    The Nature of Space and Time is a seven and a half hour long video that comes in a three tape set. Professors Hawking and Penrose are shown giving a series of one hour lectures at the Isaac Newton Institute. The topics of their talks range from the structure of space-time to the quantum theory of gravitation. They are organized along three main lines. Both speakers first discuss the singularities of space and time within the framework of classical general relativity, that is, as deduced from Einstein's equations. After giving arguments in favour of the existence of closed trapped surfaces (collapsing stars, black holes), Hawking draws a parallel between thermodynamic irreversibility and the loss of information coming from gravity trapped surfaces. Instead, Penrose insists on the mathematical structure of the singularities, using in particular the Weyl curvature to characterize them. From his analysis two classes of singularities emerge: those from which matter comes out (big bang) and those in which matter comes in (big crunch, black holes). The classical setting being recalled, the speakers turn to quantum theory. Hawking's second talk is concerned with the quantum theory of black holes. In order to account for quantum effects, he introduces a path-integral formulation over Euclideanized metrics, Armed with this tool, the validity of which he merely assumes, he proves that black holes actually radiate so that he renders fully consistent the thermodynamic analogy, entropy being replaced by the area event horizon, and statistical fluctuations by quantum fluctuations. Basing his analysis upon an interpretation in terms of information theory, there exists, Hawking asserts, a new level of unpredictability. Penrose prefers not to expand on Hawking's interpretations and starts building upon quantum mechanics (analysis of the EPR experiment) and the density matrix formalism to stress the problems caused by the nonlocality of energy. In his last lecture

  6. Approaches to radiation guidelines for space travel

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1984-01-01

    There are obvious risks in space travel that have loomed larger than any risk from radiation. Nevertheless, NASA has maintained a radiation program that has involved maintenance of records of radiation exposure, and planning so that the astronauts' exposures are kept as low as possible, and not just within the current guidelines. These guidelines are being reexamined currently by NCRP Committee 75 because new information is available, for example, risk estimates for radiation-induced cancer and about the effects of HZE particles. Furthermore, no estimates of risk or recommendations were made for women in 1970 and must now be considered. The current career limit is 400 rem. The appropriateness of this limit and its basis are being examined as well as the limits for specific organs. There is now considerably more information about age-dependency for radiation and this will be taken into account. Work has been carried out on the so-called microlesions caused by HZE particles and on the relative carcinogenic effect of heavy ions, including iron. A remaining question is whether the fluence of HZE particles could reach levels of concern in missions under consideration. Finally, it is the intention of the committee to indicate clearly the areas requiring further research. 21 references, 1 figure, 7 tables

  7. Approaches to radiation guidelines for space travel

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1984-01-01

    There are obvious risks in space travel that have loomed larger than any risk from radiation. Nevertheless, NASA has maintained a radiation program that has involved maintenance of records of radiation exposure, and planning so that the astronauts' exposures are kept as low as possible, and not just within the current guidelines. These guidelines are being reexamined currently by NCRP Committee 75 because new information is available, for example, risk estimates for radiation-induced cancer and about the effects of HZE particles. The current career limit is 400 rem to the blood forming organs. The appropriateness of this limit and its basis are being examined as well as the limits for specific organs. There is now considerably more information about age-dependency for radiation effects and this will be taken into account. In 1973 a committee of the National Research Council made a separate study of HZE particle effects and it was concluded that the attendant risks did not pose a hazard for low inclination near-earth orbit missions. Since that time work has been carried out on the so-called microlesions caused by HZE particles and on the relative carcinogenic effect of heavy ions, including iron. A remaining question is whether the fluence of HZE particles could reach levels of concern in missions under consideration. Finally, it is the intention of the committee to indicate clearly the areas requiring further research. 26 references, 1 figure, 7 tables

  8. Investigation of environmental natural penetrating radiation level in Beijing

    International Nuclear Information System (INIS)

    Wu Zengxin; Zhang Wenying; Zheng Rukuan; Wei Shujun; Ding Huiqiu

    1992-01-01

    The authors report the methods and results of investigation of environmental natural penetrating radiation level in Beijing. There were 83 measurement points selected, which were located at the vertexes of 1 x 1 km square meshes and uniformly distributed over the urban district. 173 net grid measuring points selected with grid spacing of 10 x 10 km and uniformly distributed over the suburban district. Another 131 more densely distributed points were added over some special areas. The results show that: (1) The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate over field is 56.2, 56.4 and 50.1 nGy · h -1 respectively. The γ radiation dose rate is higher in west and north area than in southeast area. (2) The point-weighted average value of natural γ radiation dose rate over roads was 49.3 nGy · h -1 . (3) The point weighted and population-weighted average value of natural γ radiation dose inside buildings was 83.5 and 77.1 nGy · h -1 respectively. (4) The weighted average of air absorbed dose rate from the ionizing components of cosmic rays (except for neutron) over point number and population was respectively 29.0 and 27.5 nGy · h -1 indoors, and 32.3 and 30.8 nGy · h -1 outdoors. (5) The point and population-weighted means of natural penetrating radiation dose rate (the contribution from neutron is not included) are 112.8 and 104.5 nGy · h -1 indoors, respectively; 88.7 and 81.3 nGy · h -1 outdoors, respectively. (6) The annual effective dose equivalent per capital people natural γ radiation, cosmic ray and natural penetrating radiation was 0.43, 0.25 and 0.68 mSv respectively, and the annual collective effective dose equivalent was 4.0, 2.3 and 6.3 x 10 3 man · Sv, respectively

  9. Distribution of Radiation Exposure from Natural Radiation in Big Cities

    International Nuclear Information System (INIS)

    Udiyani, P.M.; Ahmad, Yus R.

    2000-01-01

    The measurement of radiation exposure from the natural radiation in the big city in Java such as Jakarta, Bandung, Semarang, Yogyakarta, and Surabaya have be done. Based on radiation dose and population at the sample location, the dose collective and risk probability will be know. The maximal exposure at Yogyakarta is 0.291 mSv/year and the minimal exposure at Surabaya is 0.216 mSv/year. Collective dose at Jakarta is 1.649.526 men mSv/year; Bandung 124.844 men mSv/year; Semarang : 64.558 men mSv/year; Yogyakarta 136.188 men mSv/year; and Surabaya 145.152 men mSv/year. The person probability of radiation disease at jakarta is 16.49 person/year, Bandung is 1.24 person/year, Semarang 1.64 person/year, Yogyakarta is 1.36 person/year, and Surabaya is 1.45 person/year

  10. Radiation processing of natural rubber latex

    International Nuclear Information System (INIS)

    Makuuchi, K.; Markovic, V.

    1991-01-01

    Significant progress has been made in the last 5 years in developing new rubber material using radiation technology that holds important benefits for industries in Southeast Asia and the Pacific. A driving force behind its development has been co-ordinated research through an international programme of the IAEA and United Nations Development Programme (UNDP) known as the Regional Co-operative Agreement (RCA). The technology is called radiation vulcanization of natural rubber latex, or RVNRL. It uses high-energy gamma radiation (it also can use electron beams) to initiate vulcanization, a process that chemically bonds molecules to produce rubber elasticity and strength. As with other radiation industrial processes, products are not radioactive. In the RVNRL process, radiation energy replaces the use of a sulphur-based process and produces a material that retains all properties of the conventional product. However, it has some additional remarkable qualities: the absence of carcinogenic nitrosoamines; extremely low cytotoxicity; absence of sulphur and zinc oxide; and high transparency and softness. Rubber products for medical and hygienic uses are obviously the most promising applications of RVNRL technology because of the absence of carcinogenic and toxic products. These essential requirements are easily met by the radiation technology, and at the moment, by no other alternative. Within the technology development programme, test production of various products such as condoms, gloves, nipples, pacifiers, and toy balloons are now being carried out at different centers participating in the programme. Pilot production of condoms and gloves for medical examinations is done in Indonesia. Products are tested extensively in various field locations. Low-cost irradiators have been specifically designed for vulcanization applications, and the main parameters for estimating production costs and for conducting feasibility studies have been developed

  11. Safety of natural radiation exposure. A meta-analysis of epidemiological studies on natural radiation

    International Nuclear Information System (INIS)

    Osaki, S.

    2000-01-01

    People have been exposed every time and everywhere to natural radiation and ''intuitively'' know the safety of this radiation exposure. On the other hand the theory of no threshold value on radiological carcinogenesis is known widely, and many people feel danger with even a smallest dose of radiation exposure. The safety of natural radiation exposure can be used for the risk communication with the public. For this communication, the safety of natural radiation exposure should be proved ''scientifically''. Safety is often discussed scientifically as the risks of the mortality from many practices, and the absolute risks of safe practices on the public are 1E-5 to 1E-6. The risks based on the difference of natural radiation exposure on carcinogenesis have been analyzed by epidemiological studies. Much of the epidemiological studies have been focused on the relationship between radiation doses and cancer mortalities, and their results have been described as relative risks or correlation factors. In respect to the safety, however, absolute risks are necessary for the discussion. Cancer mortalities depend not only on radiation exposure, but also on ethnic groups, sexes, ages, social classes, foods, smoking, environmental chemicals, medical radiation, etc. In order to control these confounding factors, the data are collected from restricted groups or/and localities, but any these ecological studies can not perfectly compensate the confounding factors. So positive or negative values of relative risks or the meaningful correlation factors can not be confirmed that their values are derived originally from the difference of their exposure doses. The absolute risks on these epidemiological studies are also affected by many factors containing radiation exposure. The absolute risk or the upper value of the confidence limit obtained from the epidemiological study which is well regulated confounding factors is possible to be a maximum risk on the difference of the exposure doses

  12. The natural sources of ionizing radiation exposure

    International Nuclear Information System (INIS)

    Maximilien, R.

    1982-01-01

    Natural sources of ionizing radiation include external sources (cosmic rays, natural radionuclides present in the crust of the earth and in building materials) and internal sources (naturally occuring radionuclides in the human body, especially the potassium 40 and radon short lived decay products). The principal ways of human exposure to theses different components in ''normal'' areas are reviewed; some examples of the variability of exposure with respect to different regions of the world or the habits of life are given. Actual estimations of the doses delivered to the organs are presented; for the main contributors to population exposure, the conversion into effective dose equivalent has been made for allowing a better evaluation of their respective importance [fr

  13. Optimization of a space based radiator

    International Nuclear Information System (INIS)

    Sam, Kien Fan Cesar Hung; Deng Zhongmin

    2011-01-01

    Nowadays there is an increased demand in satellite weight reduction for the reduction of costs. Thermal control system designers have to face the challenge of reducing both the weight of the system and required heater power while maintaining the components temperature within their design ranges. The main purpose of this paper is to present an optimization of a heat pipe radiator applied to a practical engineering design application. For this study, a communications satellite payload panel was considered. Four radiator areas were defined instead of a centralized one in order to improve the heat rejection into space; the radiator's dimensions were determined considering worst hot scenario, solar fluxes, heat dissipation and the component's design temperature upper limit. Dimensions, thermal properties of the structural panel, optical properties and degradation/contamination on thermal control coatings were also considered. A thermal model was constructed for thermal analysis and two heat pipe network designs were evaluated and compared. The model that allowed better radiator efficiency was selected for parametric thermal analysis and optimization. This pursues finding the minimum size of the heat pipe network while keeping complying with thermal control requirements without increasing power consumption. - Highlights: →Heat pipe radiator optimization applied to a practical engineering design application. →The heat pipe radiator of a communications satellite panel is optimized. →A thermal model was built for parametric thermal analysis and optimization. →Optimal heat pipe network size is determined for the optimal weight solution. →The thermal compliance was verified by transient thermal analysis.

  14. The Ionizing Radiation Environment on the International Space Station: Performance vs. Expectations for Avionics and Materials

    Science.gov (United States)

    Koontz, Steven L.; Boeder, Paul A.; Pankop, Courtney; Reddell, Brandon

    2005-01-01

    The role of structural shielding mass in the design, verification, and in-flight performance of International Space Station (ISS), in both the natural and induced orbital ionizing radiation (IR) environments, is reported.

  15. The ionizing radiation environment in space and its effects

    International Nuclear Information System (INIS)

    Adams, Jim; Falconer, David; Fry, Dan

    2012-01-01

    The ionizing radiation environment in space poses a hazard for spacecraft and space crews. The hazardous components of this environment are reviewed and those which contribute to radiation hazards and effects identified. Avoiding the adverse effects of space radiation requires design, planning, monitoring and management. Radiation effects on spacecraft are avoided largely though spacecraft design. Managing radiation exposures of space crews involves not only protective spacecraft design and careful mission planning. Exposures must be managed in real time. The now-casting and forecasting needed to effectively manage crew exposures is presented. The techniques used and the space environment modeling needed to implement these techniques are discussed.

  16. DNA Damage Signals and Space Radiation Risk

    Science.gov (United States)

    Cucinotta, Francis A.

    2011-01-01

    Space radiation is comprised of high-energy and charge (HZE) nuclei and protons. The initial DNA damage from HZE nuclei is qualitatively different from X-rays or gamma rays due to the clustering of damage sites which increases their complexity. Clustering of DNA damage occurs on several scales. First there is clustering of single strand breaks (SSB), double strand breaks (DSB), and base damage within a few to several hundred base pairs (bp). A second form of damage clustering occurs on the scale of a few kbp where several DSB?s may be induced by single HZE nuclei. These forms of damage clusters do not occur at low to moderate doses of X-rays or gamma rays thus presenting new challenges to DNA repair systems. We review current knowledge of differences that occur in DNA repair pathways for different types of radiation and possible relationships to mutations, chromosomal aberrations and cancer risks.

  17. Space storms and radiation causes and effects

    CERN Document Server

    Schrijver, Carolus J

    2010-01-01

    Heliophysics is a fast-developing scientific discipline that integrates studies of the Sun's variability, the surrounding heliosphere, and the environment and climate of planets. The Sun is a magnetically variable star and for planets with intrinsic magnetic fields, planets with atmospheres, or planets like Earth with both, there are profound consequences. This 2010 volume, the second in this series of three heliophysics texts, integrates the many aspects of space storms and the energetic radiation associated with them - from causes on the Sun to effects in planetary environments. It reviews t

  18. Nuclear Cross Sections for Space Radiation Applications

    Science.gov (United States)

    Werneth, C. M.; Maung, K. M.; Ford, W. P.; Norbury, J. W.; Vera, M. D.

    2015-01-01

    The eikonal, partial wave (PW) Lippmann-Schwinger, and three-dimensional Lippmann-Schwinger (LS3D) methods are compared for nuclear reactions that are relevant for space radiation applications. Numerical convergence of the eikonal method is readily achieved when exact formulas of the optical potential are used for light nuclei (A = 16) and the momentum-space optical potential is used for heavier nuclei. The PW solution method is known to be numerically unstable for systems that require a large number of partial waves, and, as a result, the LS3D method is employed. The effect of relativistic kinematics is studied with the PW and LS3D methods and is compared to eikonal results. It is recommended that the LS3D method be used for high energy nucleon-nucleus reactions and nucleus-nucleus reactions at all energies because of its rapid numerical convergence and stability for both non-relativistic and relativistic kinematics.

  19. Criteria for radiological protection against exposure to natural radiation

    International Nuclear Information System (INIS)

    Cardenas Herrera, Juan

    2012-01-01

    Ionizing radiation includes natural radiation which has been part cosmic radiation. Radon in homes, irradiation, gamma, among others, they have also been part of ionizing radiation. The activities that have lead to natural radiation materials are: mining and processing of uranium, radio application and thorium, phosphate industry, mining and smelting of metals, oil and gas extraction, coal mining and power generation, rare earth industry and titanium, zirconium and ceramics, building materials, waste water purification. Therefore, different criteria for radiation protection have had to create against exposure to natural radiation. Distinct rules and regulations to control were created in that sense [es

  20. Non-Ionizing Radiation: Nature and Protection

    International Nuclear Information System (INIS)

    Abukasem, E.; Abdemalek, H.; Mosbah, D. S.

    2011-01-01

    Last century, the humanity witnessed a vast development, after the industrial revolution, in many aspects of life. There was a real revolution in world of communications, the electromagnetic waves were produced and used in many applications like wireless communications, radio and television transmissions, information transfer, medical diagnosis and many other useful applications. Non-ionizing radiation, the radiation which has no enough energy to remove an electron from an atom, becomes indispensable life necessity and currently it is a subject of public debate about its effects and hazards on human life and environments. The Arab Atomic Energy Agency recognized this fact and tried to raise the public awareness towards by organizing seminars, workshops and expert meetings in the Arab region in order to study the theoretical and applies aspects of this type of radiation as well as to shed the light on its possible hazards and effects on human life. This booklet came as a result of many expert meetings to be an Arabic simple and comprehensive guide line about the nature of and the different methods of protection from its possible effects and hazards.(author)

  1. Radiation vulcanization of Philippine natural rubber latex

    International Nuclear Information System (INIS)

    Dela Rosa, Alumanda M.; Abad, Lucille V.; Sta, Lorna P.; Ana-Relleve; Tranquilan-Aranilla, Charito O.; Pascual, Cristina L.

    1996-01-01

    The response of Philippine natural rubber latex to radiation vulcanization and the stability of the irradiated natural rubber latex (INRL) upon storage and aging were investigated. Commercially available high ammonia (HA) concentrated lattices obtained from various rubber plantations in Mindanao Island were treated with 5 phr of n-butyl acrylate (nBA), and gamma-irradiated at the PNRI sup 60 Co irradiation facility at dose rate of 2.57 KGy/hr. Unirradiated cast latex films gave different green strength which varied from 2 - 11 MPa. Cast films from INRL exhibited maximum tensile strengths of 25 - 32 MPa at a radiation dose of 15 kGy. Higher tensile strengths were obtained from cast films with low Mg and high nitrogen contents. Thermal analysis using thermogravimetry (TG) revealed one major decomposition product at 374 degree C - 377 degree C. Its rate of decomposition decreased to a minimum at 15 kGy, then increased as radiation dose increased. This trend correlated well with the tensile strength measurements. The stability of the INRL upon storage and aging is an essential parameter to the rubber latex industry. For storage studies, INRL was stored for various periods of time. It was found that the pH and total solids content of the stored INRL did not change significantly after 12 months of storage; the MST values remained at above 100 seconds, and the viscosity decreased with time. The cast films exhibited a decline in tensile strength, modulus 300% and crosslinking density upon storage. While there were observed changes in the physical properties of the IRNL during the storage period, the data indicate that these properties were within values acceptable to the latex industry. Tests on the aging properties of INRL film were undertaken. It was shown that among the chemical antioxidants presently used by the latex industry. TNPP demonstrated the highest antioxidant property, followed by Antage DAHQ and Vulcanox BKF. Our data indicate that the natural rubber latex

  2. Well logging with natural gamma radiation

    International Nuclear Information System (INIS)

    Ellis, D.V.

    1983-01-01

    An invention is described for use in natural gamma radiation well logging in which measurements taken in a borehole are used in the search for valuable underground resources such as oil or gas. The invention comprises deriving a log of natural gamma radiation detected in selected energy windows for a selected borehole depth interval and converting it into a log of the selected subsurface materials, e.g. Th, U, K. This log is corrected for the effects of 1) either a gamma ray emitter in the borehole fluid, e.g. potassium salts and/or 2) a gamma ray attenuator in the borehole fluid, e.g. a strong attenuator such as barite and/or hematite. The Th, U, K log is particularly useful in the exploration of oil and gas resources since the Th, U, K concentrations are a good indication as to the presence, type and volume of shale and clay in the formations surrounding the borehole. (U.K.)

  3. European activities in space radiation biology and exobiology

    International Nuclear Information System (INIS)

    Horneck, G.

    1996-01-01

    In view of the space station era, the European Space Agency has initiated a review and planning document for space life sciences. Radiation biology includes dosimetry of the radiation field and its modification by mass shielding, studies on the biological responses to radiation in space, on the potential impact of space flight environment on radiation effects, and assessing the radiation risks and establishing radiation protection guidelines. To reach a better understanding of the processes leading to the origin, evolution and distribution of life, exobiological activities include the exploration of the solar system, the collection and analysis of extraterrestrial samples and the utilization of space as a tool for testing the impact of space environment on organics and resistant life forms. (author)

  4. Ionizing radiation in earth's atmosphere and in space near earth.

    Science.gov (United States)

    2011-05-01

    The Civil Aerospace Medical Institute of the FAA is charged with identifying health hazards in air travel and in : commercial human space travel. This report addresses one of these hazards ionizing radiation. : Ionizing radiation is a subatomic p...

  5. NASA space radiation transport code development consortium

    International Nuclear Information System (INIS)

    Townsend, L. W.

    2005-01-01

    Recently, NASA established a consortium involving the Univ. of Tennessee (lead institution), the Univ. of Houston, Roanoke College and various government and national laboratories, to accelerate the development of a standard set of radiation transport computer codes for NASA human exploration applications. This effort involves further improvements of the Monte Carlo codes HETC and FLUKA and the deterministic code HZETRN, including developing nuclear reaction databases necessary to extend the Monte Carlo codes to carry out heavy ion transport, and extending HZETRN to three dimensions. The improved codes will be validated by comparing predictions with measured laboratory transport data, provided by an experimental measurements consortium, and measurements in the upper atmosphere on the balloon-borne Deep Space Test Bed (DSTB). In this paper, we present an overview of the consortium members and the current status and future plans of consortium efforts to meet the research goals and objectives of this extensive undertaking. (authors)

  6. Natural radiation contribution to renewable energy searching

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar, M.; Lopez, A. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Flores, M.; Huerta, M., E-mail: miguel.balcazar@inin.gob.mx [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Alejandro Volta 655, 58290 Morelia, Michoacan (Mexico)

    2014-08-15

    High anomalies of naturally occurring radon in geothermal fields are becoming an additional geophysics tool for determining the areas of geothermal activity underground. Under close collaboration with the Federal Electricity Board in Mexico (CFE), we have study four geothermal fields (Los Azufres, Tres Virgenes, Humeros and Acoculco) for extending the energy potentially. The heat source in hydrothermal systems produces geothermal gasses, which transport radon to the surface faster than the common diffusion process in absence of a geothermal activity. This paper presents: mechanism of radon production, main physical and chemical features that make it an excellent indicator for locating heat sources of geothermal reservoirs, the detection basis of in situ radon concentration using a high sensitive radiation chamber and the planning experimental strategy for successful use of this technique. (author)

  7. Natural radiation contribution to renewable energy searching

    International Nuclear Information System (INIS)

    Balcazar, M.; Lopez, A.; Flores, M.; Huerta, M.

    2014-08-01

    High anomalies of naturally occurring radon in geothermal fields are becoming an additional geophysics tool for determining the areas of geothermal activity underground. Under close collaboration with the Federal Electricity Board in Mexico (CFE), we have study four geothermal fields (Los Azufres, Tres Virgenes, Humeros and Acoculco) for extending the energy potentially. The heat source in hydrothermal systems produces geothermal gasses, which transport radon to the surface faster than the common diffusion process in absence of a geothermal activity. This paper presents: mechanism of radon production, main physical and chemical features that make it an excellent indicator for locating heat sources of geothermal reservoirs, the detection basis of in situ radon concentration using a high sensitive radiation chamber and the planning experimental strategy for successful use of this technique. (author)

  8. Natural radiation dose estimates from soils

    International Nuclear Information System (INIS)

    Silveira, M.A.G.R.; Moreira, H.; Medina, N.H.

    2009-01-01

    In this work the natural radiation from soils of southeastern Brazil has been studied. Soil samples from Interlagos, Sao Paulo; parks and Billings dam, in Sao Bernardo do Campo city; Santos, Sao Vicente and Sao Sebastiao beaches, Sao Paulo and sands from Ilha Grande beaches, Rio de Janeiro, were analyzed. The results show that the main contribution to the effective dose is due to elements of the 232 Th decay chain, with a smaller contribution from the radionuclide 40 K and the elements of the series of 238 U. The obtained values found in the studied regions, are around the average international dose due to external exposure to gamma rays (0.48 mSv/yr), except in Praia Preta, Ilha Grande, where the effective dose exceeds the average value. (author)

  9. Space Radiation Effect on Si Solar Cells

    Directory of Open Access Journals (Sweden)

    Jae-Jin Lee

    2008-12-01

    Full Text Available High energy charged particles are trapped by geomagnetic field in the region named Van Allen Belt. These particles can move to low altitude along magnetic field and threaten even low altitude spacecraft. Space Radiation can cause equipment failures and on occasions can even destroy operations of satellites in orbit. Sun sensors aboard Science and Technology Satellite (STSAT-1 was designed to detect sun light with silicon solar cells which performance was degraded during satellite operation. In this study, we try to identify which particle contribute to the solar cell degradation with ground based radiation facilities. We measured the short circuit current after bombarding electrons and protons on the solar cells same as STSAT-1 sun sensors. Also we estimated particle flux on the STSAT-1 orbit with analyzing NOAA POES particle data. Our result clearly shows STSAT-1 solar cell degradation was caused by energetic protons which energy is about 700 keV to 1.5 MeV. Our result can be applied to estimate solar cell conditions of other satellites.

  10. Lightweight Radiator Fins for Space Nuclear Power, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase 1 project shall investigate concept radiator fins that incorporate novel carbon materials for improved performance of segmented high temperature...

  11. Titanium Loop Heat Pipes for Space Nuclear Radiators, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project will develop titanium Loop Heat Pipes (LHPs) that can be used in low-mass space nuclear radiators, such as...

  12. Space Qualified, Radiation Hardened, Dense Monolithic Flash Memory, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Radiation hardened nonvolatile memories for space is still primarily confined to EEPROM. There is high density effective or cost effective NVM solution available to...

  13. Space Qualified, Radiation Hardened, Dense Monolithic Flash Memory, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Space Micro proposes to build a radiation hardened by design (RHBD) flash memory, using a modified version of our RH-eDRAM Memory Controller to solve all the single...

  14. The Nasa space radiation school, an excellent training in radiobiology and space radiation protection

    International Nuclear Information System (INIS)

    Vogin, G.

    2009-01-01

    The astronauts have to spend more time in space and the colonization of the moon and Mars are in the cross hairs of international agencies. The cosmic radiation from which we are protected on ground by atmosphere and by the terrestrial magnetosphere (.4 mSv/year according to Who) become really threatening since 20 km altitude, delivering an average radiation dose of a therapeutic kind to astronauts with peaks related to solar events. It is composed in majority of hadrons: protons (85%) and heavy ions (13%), but also photons (2%) of high energy (GeV/n)). the incurred risks are multiple: early ones(cataract, central nervous system damages, whole body irradiation) but especially delayed ones (carcinogenesis). The astronauts radiation protection turns poor and the rate of death risk by cancer returning from a mission on Mars has been estimated at 5%. The Nasa created in 2004 a summer school aiming to awareness young researchers to the space radiobiology specificities. Areas concerned as follow: radioinduced DNA damage and repair, cell cycle, apoptosis, bystander effect, genome instability, neuro degeneration, delayed effects and carcinogenesis in relation with radiation exposure. (N.C.)

  15. Radiation Measured for Chinese Satellite SJ-10 Space Mission

    Science.gov (United States)

    Zhou, Dazhuang; Sun, Yeqing; Zhang, Binquan; Zhang, Shenyi; Sun, Yueqiang; Liang, Jinbao; Zhu, Guangwu; Jing, Tao; Yuan, Bin; Zhang, Huanxin; Zhang, Meng; Wang, Wei; Zhao, Lei

    2018-02-01

    Space biological effects are mainly a result of space radiation particles with high linear energy transfer (LET); therefore, accurate measurement of high LET space radiation is vital. The radiation in low Earth orbits is composed mainly of high-energy galactic cosmic rays (GCRs), solar energetic particles, particles of radiation belts, the South Atlantic Anomaly, and the albedo neutrons and protons scattered from the Earth's atmosphere. CR-39 plastic nuclear track detectors sensitive to high LET are the best passive detectors to measure space radiation. The LET method that employs CR-39 can measure all the radiation LET spectra and quantities. CR-39 detectors can also record the incident directions and coordinates of GCR heavy ions that pass through both CR-39 and biosamples, and the impact parameter, the distance between the particle's incident point and the seed's spore, can then be determined. The radiation characteristics and impact parameter of GCR heavy ions are especially beneficial for in-depth research regarding space radiation biological effects. The payload returnable satellite SJ-10 provided an excellent opportunity to investigate space radiation biological effects with CR-39 detectors. The space bio-effects experiment was successfully conducted on board the SJ-10 satellite. This paper introduces space radiation in low Earth orbits and the LET method in radiation-related research and presents the results of nuclear tracks and biosamples hitting distributions of GCR heavy ions, the radiation LET spectra, and the quantities measured for the SJ-10 space mission. The SJ-10 bio-experiment indicated that radiation may produce significant bio-effects.

  16. Naturally occuring radiation in the Nordic countries - recommendations

    International Nuclear Information System (INIS)

    1986-01-01

    In the publication ''Report on the Applicability of International Radiation Protection Recommendations in the Nordic Countries'', published in 1976, the radiation protection authorities in Denmark, Finland, Iceland, Norway and Sweden expessed their agreement on the main principles of radiation protection. The general aspects of radiation protection were covered in the recommendations with the exception of exposure of the public from natural sources of radiation. In 1983 a working group published the report ''Naturally Occurring radiation in the Nordic Countries, - Levels'' in the Radiation Protection Information-Series from the Nordic countries. In that report the present knowledge of the population exposure from natural sources of external gamma-radiation and from radon and thoron daughters in air was reviewed as a basis for the development of the radiation protection recommendations for natural radiation. During preparation of these recommendations due account has also been taken of ICRP publication no. 39: ''Principles for Limiting Exposure of the Public to Natural Sources of Radiation'', which was published in 1984 and in which ICRP for the first time has issued more specific recommendations for natural sources. The recommendations may serve as a basis for more formal rules and regulations within each country, if this is seemed necessary. However, no attempt has been made to formulate identical rules for all the five countries since the exposure levels from natural sources, methods of application and the legal frameworks differ between the countries. (EG)

  17. Criteria for radiological protection against exposure to natural radiation

    International Nuclear Information System (INIS)

    Cardenas Herrera, Juan

    2012-01-01

    Exposure of humans to natural sources of radiation has been a continuous and inevitable feature of life on earth. This exposure exceeds all due to artificial sources combined for most people. Many exposures to natural radiation sources are modified by human action. In particular, natural radionuclides are released into the environment in mineral processing and in activities such as the production of phosphate fertilizers and the use of fossil fuels. An increase of exposures to this natural radiation is caused. The relevance of exposure to natural radiation is confirmed by the fact that, for most people, the exposures to natural background radiation have been much more significant than exposures to artificial sources, with exceptions. Among these exceptions have been noted: medical exposures, accidents with release of radionuclides and some specific workplaces. In all cases, however, the natural background radiation has formed the basis on which all the others exposures are added and is a common level serving as compared to other exposures. Regulations and instructions have begun to establish in some countries to regulate natural radiation, countries like Spain, have already incorporated into its regulations on health protection against ionizing radiation the subject of natural radiation. (author) [es

  18. Biological Effects of Space Radiation and Development of Effective Countermeasures

    OpenAIRE

    Kennedy, Ann R.

    2014-01-01

    As part of a program to assess the adverse biological effects expected from astronaut exposure to space radiation, numerous different biological effects relating to astronaut health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death an...

  19. Role of natural radiation environment in earth sciences

    International Nuclear Information System (INIS)

    Vohra, K.G.

    1980-01-01

    Natural ionizing radiations play an important role in a wide spectrum of earth sciences, including meteorology, geophysics, hydrology, atmospheric physics, and atmospheric chemistry. The nature and distribution of ionizing radiation sources and natural radionuclides in the atmospheric environment are summarized. The present status of the use of natural radioactive tracers for atmospheric studies is discussed. The effect of ionization produced by natural radiation sources on atmospheric electricity, the relationship of electrical and meteorological variables, and the possible effects of man-made releases of 85 Kr are considered. Experimental evidence is presented for the production of condensation nuclei by the combined effects of radon and sulfur dioxide

  20. Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

    Directory of Open Access Journals (Sweden)

    Jeffery C. Chancellor

    2014-09-01

    Full Text Available Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO. Shielding is an effective countermeasure against solar particle events (SPEs, but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other “omics” areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts.

  1. Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

    Science.gov (United States)

    Chancellor, Jeffery C.; Scott, Graham B. I.; Sutton, Jeffrey P.

    2014-01-01

    Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS) decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO). Shielding is an effective countermeasure against solar particle events (SPEs), but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR) nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other “omics” areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts. PMID:25370382

  2. Natural ionizing radiation and human health in Serbia

    Directory of Open Access Journals (Sweden)

    Obradović-Arsić Danijela R.

    2010-01-01

    Full Text Available This paper provides information about potential effects of natural ionizing radiation on general population health. Natural radionuclides are particularly stressed, as well as health effects of high and lower doses. Radio-ecological areals have been presented for Serbia, while radiation risk has been assessed for the population of Serbia according to census years.

  3. Technologically modified exposures to natural radiation. Annex C

    International Nuclear Information System (INIS)

    1982-01-01

    This Annex deals with some examples of technologically modified exposures to natural radiation. Radiation exposures due to coal-fired power plants, geothermal energy production, exploitation of phosphate rock, aircraft travel, and consumer products are discussed. The present state of knowledge does not allow an accurate estimate of the collective effective dose equivalent from technologically modified exposures to natural radiation to be made. This annex has an extensive bibliography with at least 200 references.

  4. CAD-based radiation protection and shielding in space

    International Nuclear Information System (INIS)

    Appleby, M.H.

    1991-01-01

    In the not-too-distant future, astronauts will begin living and working on space station Freedom (SSF), eventually establishing a permanent presence in space. Beyond Freedom, the National Aeronautics and Space Administration (NASA) has set its sights on returning to and eventually establishing outposts on the moon and Mars. Without appropriate methods of identifying protection deficiencies, spacecraft designers often overestimate or defer shielding solutions in both cases burdening the program. To avoid possible penalties such as increased mass, complexity, and cost, radiation analysis should be conducted as part of the preliminary design process. An innovative radiation assessment system combining computer-aided design (CAD) capabilities with established NASA transport codes has been developed permitting fast, accurate analysis of spacecraft. The use of this automated analytical tool the Boeing Radiation Exposure Model (Brem) is discussed in this paper, relative to spacecraft design and the optimization of radiation shielding. Results obtained from recently completed radiation analysis of space station Freedom are also discussed

  5. A Monte Carlo transport code study of the space radiation environment using FLUKA and ROOT

    CERN Document Server

    Wilson, T; Carminati, F; Brun, R; Ferrari, A; Sala, P; Empl, A; MacGibbon, J

    2001-01-01

    We report on the progress of a current study aimed at developing a state-of-the-art Monte-Carlo computer simulation of the space radiation environment using advanced computer software techniques recently available at CERN, the European Laboratory for Particle Physics in Geneva, Switzerland. By taking the next-generation computer software appearing at CERN and adapting it to known problems in the implementation of space exploration strategies, this research is identifying changes necessary to bring these two advanced technologies together. The radiation transport tool being developed is tailored to the problem of taking measured space radiation fluxes impinging on the geometry of any particular spacecraft or planetary habitat and simulating the evolution of that flux through an accurate model of the spacecraft material. The simulation uses the latest known results in low-energy and high-energy physics. The output is a prediction of the detailed nature of the radiation environment experienced in space as well a...

  6. Status Report of Simulated Space Radiation Environment Facility

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Phil Hyun; Nho, Young Chang; Jeun, Joon Pyo; Choi, Jae Hak; Lim, Youn Mook; Jung, Chan Hee; Jeon, Young Kyu

    2007-11-15

    The technology for performance testing and improvement of materials which are durable at space environment is a military related technology and veiled and securely regulated in advanced countries such as US and Russia. This core technology cannot be easily transferred to other country too. Therefore, this technology is the most fundamental and necessary research area for the successful establishment of space environment system. Since the task for evaluating the effects of space materials and components by space radiation plays important role in satellite lifetime extension and running failure percentage decrease, it is necessary to establish simulated space radiation facility and systematic testing procedure. This report has dealt with the status of the technology to enable the simulation of space environment effects, including the effect of space radiation on space materials. This information such as the fundamental knowledge of space environment and research status of various countries as to the simulation of space environment effects of space materials will be useful for the research on radiation hardiness of the materials. Furthermore, it will be helpful for developer of space material on deriving a better choice of materials, reducing the design cycle time, and improving safety.

  7. Naturally occurring and radiation-induced tumors in SPF mice, and genetic influence in radiation leukemogenesis

    International Nuclear Information System (INIS)

    Kasuga, T.

    1979-01-01

    The data obtained so far in this study point to a strong genetic influence not only on the types and incidence of naturally occurring and radiation-induced tumors but also on radiation leukemogenesis. (Auth.)

  8. Space radiation interaction mechanisms in materials

    Science.gov (United States)

    Wilson, J. W.

    1983-01-01

    Models of charged-particle impact under conditions typical of the space environment are reported, with a focus on impact excitation and nuclear reactions, especially for heavy ions. Impact excitation is studied by using a global model for electronic excitation based on formal relations through the classical dielectric function to derive an approximation related to the local plasma (electron density distribution) within the atoms and molecules; and corrections to the model resulting from the nonfluid nature of this plasma are discussed. Nuclear reactions are studied by reducing quantum-mechanical treatment of this general N-body problem to an equivalent two-body problem that is solvable, and by comparing the results with experimental data. The equations for heavy-charged-particle transport are derived and solution techniques demonstrated. Finally, these methods of analysis are applied to study the change in the electrical properties of a GaAs semiconductor for photovoltaic applications; proton damage to GaAs crystals is found to arise from stable replacement defects and to be nonannealable, in contrast to electron-induced damage.

  9. Space Radiation Effects in Inflatable and Composite Habitat Materials

    Science.gov (United States)

    Waller, Jess; Rojdev, Kristina

    2015-01-01

    This Year 2 project provides much needed risk reduction data to assess solar particle event (SPE) and galactic cosmic ray (GCR) space radiation damage in existing and emerging materials used in manned low-earth orbit, lunar, interplanetary, and Martian surface missions. More specifically, long duration (up to 50 years) space radiation damage is quantified for materials used in inflatable structures (1st priority), and habitable composite structures and space suits materials (2nd priority). The data collected has relevance for nonmetallic materials (polymers and composites) used in NASA missions where long duration reliability is needed in continuous or intermittent radiation fluxes.

  10. Epistemological limitation for attributing health effects to natural radiation exposure

    International Nuclear Information System (INIS)

    González, Abel J.

    2010-01-01

    The attribution of health effects to prolonged radiation exposure situations, such as those experienced in nature, is a challenging problem. The paper describes the epistemological limitations for such attribution it demonstrate that in most natural exposure situations, the theory of radiation-related sciences is not capable to provide the scientific evidence that health effects actually occur (or do not occur) and, therefore, that radiation effects are attributable to natural exposure situations and imputable to nature. Radiation exposure at high levels is known to provoke health effects as tissue reactions. If individuals experience these effects they can be attributed to the specific exposure with a high degree of confidence under the following conditions: the dose incurred have been higher that the relevant dose-threshold for the specific effect; and an unequivocal pathological diagnosis is attainable ensuring that possible competing causes have been eliminated. Only under these conditions, the occurrence of the effect may be properly attested and attributed to the exposure. However, even high levels of natural radiation exposure are lower than relevant dose-thresholds for tissue reactions and, therefore, natural radiation exposure is generally unable to cause these type of effects. One exception to this general rule could be situations of high levels of natural radiation exposure that might be sufficient to induce opacities in the lens of the eyes (which could be considered a tissue-reaction type of effect)

  11. Natural background radiation and population dose in China

    Energy Technology Data Exchange (ETDEWEB)

    Guangzhi, C. (Ministry of Public Health, Beijing, BJ (China)); Ziqiang, P.; Zhenyum, H.; Yin, Y.; Mingqiang, G.

    On the basis of analyzing the data for the natural background radiation level in China, the typical values for indoor and outdoor terrestrial gamma radiation and effective dose equivalents from radon and thoron daughters are recommended. The annual effective dose equivalent from natural radiation to the inhabitant is estimated to be 2.3 mSv, in which 0.54 mSv is from terrestrial gamma radiation and about 0,8 mSv is from radon and its short-lived daughters. 55 Refs.

  12. Cosmic microwave background radiation in an inhomogeneous spherical space

    International Nuclear Information System (INIS)

    Aurich, R; Lustig, S; Kramer, P

    2011-01-01

    We analyse the cosmic microwave background (CMB) radiation in spherical three-spaces with nontrivial topology. The focus is on an inhomogeneous space which possesses observer-dependent CMB properties. The suppression of the CMB anisotropies on large angular scales is analysed with respect to the position of the CMB observer. The equivalence of a lens space to a Platonic cubic space is shown and used for the harmonic analysis. We give the transformation of the CMB multipole radiation amplitude as a function of the position of the observer. General sum rules are obtained in terms of the squares of the expansion coefficients for invariant polynomials on the three-sphere.

  13. Study of integrated circuits in natural space environment

    International Nuclear Information System (INIS)

    Karoui, S.

    1993-11-01

    In this thesis we study one of the critical phenomena induced by the radiation of integrated circuits in the natural space environment: the so-called upset phenomenon. This phenomenon, caused by a heavy-ion strike on circuit sensitive areas, result in the modification of the information stored in a memory element. Upsets may then perturb the functioning of satellite-borne complex processors with serious consequences on the control of equipments operating in space. As commonly used processes or design hardening techniques cannot guarantee a total immunity against upsets, provisional methods are generally adopted to select the less sensitive circuits among components to be used in a space application. These methods consist in the simulation of the irradiated environment by means of particle accelerators, to get experimental figures about the upset sensitivity of the considered circuit, and the use of these measures to estimate the in orbit circuit vulnerability. To implement such experiments on different processor types, we have designed and developed a dedicated test system, the FUTE 16 tester. This tester has been used in several test experiments where irradiated environment was simulated by means of particle accelerators. The activity of the target circuit during the irradiation could have a great influence on the measured upset sensitivity. Generally used test sequences so-called ''register test'', consist on the initialization of accessible registers with known data, and the observation of their content after a given delay to detect errors due to upsets. The main goal of this thesis is to compare in orbit error rate estimations obtained with register tests, to those obtained with ''application like'' test sequences. Both kinds of test sequences have been used during heavy-ion test experiments performed on commercially available CISC and RISC processors. The results obtained clearly show that using ''register tests'' may lead to wrong decisions in the selections

  14. Galactic cosmic ray simulation at the NASA Space Radiation Laboratory

    Science.gov (United States)

    Norbury, John W.; Schimmerling, Walter; Slaba, Tony C.; Azzam, Edouard I.; Badavi, Francis F.; Baiocco, Giorgio; Benton, Eric; Bindi, Veronica; Blakely, Eleanor A.; Blattnig, Steve R.; Boothman, David A.; Borak, Thomas B.; Britten, Richard A.; Curtis, Stan; Dingfelder, Michael; Durante, Marco; Dynan, William S.; Eisch, Amelia J.; Elgart, S. Robin; Goodhead, Dudley T.; Guida, Peter M.; Heilbronn, Lawrence H.; Hellweg, Christine E.; Huff, Janice L.; Kronenberg, Amy; La Tessa, Chiara; Lowenstein, Derek I.; Miller, Jack; Morita, Takashi; Narici, Livio; Nelson, Gregory A.; Norman, Ryan B.; Ottolenghi, Andrea; Patel, Zarana S.; Reitz, Guenther; Rusek, Adam; Schreurs, Ann-Sofie; Scott-Carnell, Lisa A.; Semones, Edward; Shay, Jerry W.; Shurshakov, Vyacheslav A.; Sihver, Lembit; Simonsen, Lisa C.; Story, Michael D.; Turker, Mitchell S.; Uchihori, Yukio; Williams, Jacqueline; Zeitlin, Cary J.

    2017-01-01

    Most accelerator-based space radiation experiments have been performed with single ion beams at fixed energies. However, the space radiation environment consists of a wide variety of ion species with a continuous range of energies. Due to recent developments in beam switching technology implemented at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), it is now possible to rapidly switch ion species and energies, allowing for the possibility to more realistically simulate the actual radiation environment found in space. The present paper discusses a variety of issues related to implementation of galactic cosmic ray (GCR) simulation at NSRL, especially for experiments in radiobiology. Advantages and disadvantages of different approaches to developing a GCR simulator are presented. In addition, issues common to both GCR simulation and single beam experiments are compared to issues unique to GCR simulation studies. A set of conclusions is presented as well as a discussion of the technical implementation of GCR simulation. PMID:26948012

  15. Radiation Hard Space Wire Gigabit Ethernet Compatible Transponder, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — High-bandwidth, Radiation Hardening, low-power, low-EMI, easily reconfigurable and upgradeable transponder-based interconnects between processor nodes, subsystems,...

  16. Spectral Analysis in High Radiation Space Backgrounds with Robust Fitting

    Science.gov (United States)

    Lasche, G. P.; Coldwell, R. L.; Nobel, L. A.; Rester, A. C.; Trombka, J. I.

    1997-01-01

    Spectral analysis software is tested for its ability to fit spectra from space. The approach, which emphasizes the background shape function, is uniquely suited to the identification of weak-strength nuclides in high-radiation background environments.

  17. Optical Real-Time Space Radiation Monitor, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Real-time dosimetry is needed to provide immediate feedback, so astronauts can minimize their exposure to ionizing radiation during periods of high solar activity....

  18. Nanodosimetry-based quality factors for radiation protection in space

    International Nuclear Information System (INIS)

    Schulte, Reinhard W.; Wroe, Andrew J.; Bashkirov, Vladimir A.; Garty, Guy Y.; Breskin, Amos; Chechik, Rachel; Shchemelinin, Sergei; Gargioni, Elisabetta; Grosswendt, Bernd; Rosenfeld, Anatoly B.

    2008-01-01

    Evaluation and monitoring of the cancer risk from space radiation exposure is a crucial requirement for the success of long-term space missions. One important task in the risk calculation is to properly weigh the various components of space radiation dose according to their assumed contribution to the cancer risk relative to the risk associated with radiation of low ionization density. Currently, quality factors of radiation both on the ground and in space are defined by national and international commissions based on existing radiobiological data and presumed knowledge of the ionization density distribution of the radiation field at a given point of interest. This approach makes the determination of the average quality factor of a given radiation field a rather complex task. In this contribution, we investigate the possibility to define quality factors of space radiation exposure based on nanodosimetric data. The underlying formalism of the determination of quality factors on the basis of nanodosimetric data is described, and quality factors for protons and ions (helium and carbon) of different energies based on simulated nanodosimetric data are presented. The value and limitations of this approach are discussed. (orig.)

  19. Radiation Transport Tools for Space Applications: A Review

    Science.gov (United States)

    Jun, Insoo; Evans, Robin; Cherng, Michael; Kang, Shawn

    2008-01-01

    This slide presentation contains a brief discussion of nuclear transport codes widely used in the space radiation community for shielding and scientific analyses. Seven radiation transport codes that are addressed. The two general methods (i.e., Monte Carlo Method, and the Deterministic Method) are briefly reviewed.

  20. Natural radiation and radioactivity in education

    International Nuclear Information System (INIS)

    Sakanoue, Masanobu

    1999-01-01

    To understand radiation and radioactivity, it is important to recall the history of their investigation. At first, the works made by Elster and Geitel with a leaf electroscope about 100 years age are introduced. Then the variations of environmental radiation level are shown by the results obtained with a large volume NaI(Tl) detector on my car travelling all over Japan and the data with a pocket dosimeter during my tours in Europe. Among environmental radioactivity, radon and tritium are specially remarked from the historical and educational points of view, with various methods for their measurements. (author)

  1. Natural radiation and radioactivity in education

    Energy Technology Data Exchange (ETDEWEB)

    Sakanoue, Masanobu [Kanazawa Univ., Takarazuka, Hyogo (Japan)

    1999-09-01

    To understand radiation and radioactivity, it is important to recall the history of their investigation. At first, the works made by Elster and Geitel with a leaf electroscope about 100 years age are introduced. Then the variations of environmental radiation level are shown by the results obtained with a large volume NaI(Tl) detector on my car travelling all over Japan and the data with a pocket dosimeter during my tours in Europe. Among environmental radioactivity, radon and tritium are specially remarked from the historical and educational points of view, with various methods for their measurements. (author)

  2. Protection against natural radiation: Optimisation and decision exercises

    International Nuclear Information System (INIS)

    O'Riordan, M.C.

    1984-02-01

    Six easy exercises are presented in which cost-benefit analysis is used to optimise protection against natural radiation or to decide whether protection is appropriate. The exercises are illustrative only and do not commit the Board. (author)

  3. Radiation - Risk and protection in manned space flight

    Energy Technology Data Exchange (ETDEWEB)

    Petrov, V.M.; Kovalev, E.E.; Sakovich, V.A.

    1981-09-01

    Radiation hazard for cosmonauts and necessary protective measures are considered. The radiation is either permanent, such as in the inner terrestrial radiation belts, or temporary, such as in the fluctuating outer belts, from solar flares, or from cosmic ray showers. An effective level of 33 rem is offered as a justified risk dose, based on U.S.S.R. and international safety standards. Estimated radiation levels are provided for a one year spaceflight, noting that exposures to 50 rem doses should be more than one month apart. Increased orbital inclination, lengthy flight duration, and higher orbits all lead to increased radiation risks, and shielding with aluminum to 5 g/sq cm is recommended, along with a radiation shelter for long term workers on space stations. The calculated permissible dose rates are designed to bring the probabilities of death due to tumors caused by radiation in line with hazards faced in other occupations, such as test pilots.

  4. Acceptability of risk from radiation: Application to human space flight

    International Nuclear Information System (INIS)

    1997-01-01

    This one of NASA's sponsored activities of the NCRP. In 1983, NASA asked NCRP to examine radiation risks in space and to make recommendations about career radiation limits for astronauts (with cancer considered as the principal risk). In conjunction with that effort, NCRP was asked to convene this symposium; objective is to examine the technical, strategic, and philosophical issues pertaining to acceptable risk and radiation in space. Nine papers are included together with panel discussions and a summary. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database

  5. Acceptability of risk from radiation: Application to human space flight

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-30

    This one of NASA`s sponsored activities of the NCRP. In 1983, NASA asked NCRP to examine radiation risks in space and to make recommendations about career radiation limits for astronauts (with cancer considered as the principal risk). In conjunction with that effort, NCRP was asked to convene this symposium; objective is to examine the technical, strategic, and philosophical issues pertaining to acceptable risk and radiation in space. Nine papers are included together with panel discussions and a summary. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  6. Current Status of Radiation Processing of Natural Polymers in India

    International Nuclear Information System (INIS)

    Ramnani, S.P.

    2010-01-01

    Radiation processing is being used on commercial basis in India since 1974 with the operation of ISOMED plant for radiation sterilization of medical products and Electron beam machine (ILU-6) in 1986. Since then many new products and processes have been investigated and some of them have culminated into useful applications. Many Indian industries produce and process natural polymers for local consumption and export. India exports about 120,000 tons of polysaccharides every year. Natural polysaccharides like guar gum, gum acacia, gum tora, agar, psylium husk etc are treated with gamma radiation mainly for controlling microbial contamination and sterilization. Radiation processing has also been used to reduce molecular weight of the polysaccharides in some applications. Recently, a few new applications have emerged where natural polysaccharides are used as additives and which play important role in controlling basic radiation chemistry reactions to produce useful products. Developed at BARC, radiation processed wound dressings, superabsorbent materials and low molecular weight chitosan are the products which have been used and could find potential applications in health care and agriculture sector. Radiation processed hydrogel wound dressings containing natural polysaccharides have already been commercialized. Some of the applications recently developed at BARC using natural polymers are briefly described below

  7. Space weather effects measured in atmospheric radiation on aircraft

    Science.gov (United States)

    Tobiska, W. K.; Bouwer, D.; Bailey, J. J.; Didkovsky, L. V.; Judge, K.; Wieman, S. R.; Atwell, W.; Gersey, B.; Wilkins, R.; Rice, D.; Schunk, R. W.; Bell, L. D.; Mertens, C. J.; Xu, X.; Wiltberger, M. J.; Wiley, S.; Teets, E.; Shea, M. A.; Smart, D. F.; Jones, J. B. L.; Crowley, G.; Azeem, S. I.; Halford, A. J.

    2016-12-01

    Space weather's effects upon the near-Earth environment are due to dynamic changes in the energy transfer processes from the Sun's photons, particles, and fields. Of the domains that are affected by space weather, the coupling between the solar and galactic high-energy particles, the magnetosphere, and atmospheric regions can significantly affect humans and our technology as a result of radiation exposure. Since 2013 Space Environment Technologies (SET) has been conducting observations of the atmospheric radiation environment at aviation altitudes using a small fleet of six instruments. The objective of this work is to improve radiation risk management in air traffic operations. Under the auspices of the Automated Radiation Measurements for Aerospace Safety (ARMAS) and Upper-atmospheric Space and Earth Weather eXperiment (USEWX) projects our team is making dose rate measurements on multiple aircraft flying global routes. Over 174 ARMAS and USEWX flights have successfully demonstrated the operation of a micro dosimeter on commercial aviation altitude aircraft that captures the radiation environment resulting from Galactic Cosmic Rays (GCRs), Solar Energetic Protons (SEPs), and outer radiation belt energetic electrons. The real-time radiation exposure is measured as an absorbed dose rate in silicon and then computed as an ambient dose equivalent rate for reporting dose relevant to radiative-sensitive organs and tissue in units of microsieverts per hour. ARMAS total ionizing absorbed dose is captured on the aircraft, downlinked in real-time, processed on the ground into ambient dose equivalent rates, compared with NASA's Langley Research Center (LaRC) most recent Nowcast of Atmospheric Ionizing Radiation System (NAIRAS) global radiation climatology model runs, and then made available to end users. Dose rates from flight altitudes up to 56,700 ft. are shown for flights across the planet under a variety of space weather conditions. We discuss several space weather

  8. Radiological Protection Experience with natural sources of radiation

    International Nuclear Information System (INIS)

    Quindos, L. S.; Fernandez, P. L.; Vinuela, J.; Arteche, J.; Sainz, G.; Gomez, J.; Matarranz

    2003-01-01

    During the last twenty five years the research Radon Group of the Medical Physics Unit of the University of Cantabria has been involved in projects concerning the measurement of natural radiation, in special that coming from radon gas. At this moment we have available for this field a lot of information in different formats, as paper, video and CD, interesting not only for public in general but also for professionals interested in the evaluation of doses coming from natural sources of radiation. (Author)

  9. Combined injury syndrome in space-related radiation environments

    Science.gov (United States)

    Dons, R. F.; Fohlmeister, U.

    The risk of combined injury (CI) to space travelers is a function of exposure to anomalously large surges of a broad spectrum of particulate and photon radiations, conventional trauma (T), and effects of weightlessness including decreased intravascular fluid volume, and myocardial deconditioning. CI may occur even at relatively low doses of radiation which can synergistically enhance morbidity and mortality from T. Without effective countermeasures, prolonged residence in space is expected to predispose most individuals to bone fractures as a result of calcium loss in the microgravity environment. Immune dysfunction may occur from residence in space independent of radiation exposure. Thus, wound healing would be compromised if infection were to occur. Survival of the space traveler with CI would be significantly compromised if there were delays in wound closure or in the application of simple supportive medical or surgical therapies. Particulate radiation has the potential for causing greater gastrointestinal injury than photon radiation, but bone healing should not be compromised at the expected doses of either type of radiation in space.

  10. The radiation protection problems of high altitude and space flight

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1993-01-01

    This paper considers the radiation environment in aircraft at high altitudes and spacecraft in low earth orbit and in deep space and the factors that influence the dose equivalents. Altitude, latitude and solar cycle are the major influences for flights below the radiation belts. In deep space, solar cycle and the occurrence of solar particle events are the factors of influence. The major radiation effects of concern are cancer and infertility in males. In high altitude aircraft the radiation consists mainly of protons and neutrons, with neutrons contributing about half the equivalent dose. The average dose rate at altitudes of transcontinental flights that approach the polar regions are greater by a factor of about 2.5 than on routes at low latitudes. Current estimates of does to air crews suggest they are well within the ICRP (1990) recommended dose limits for radiation workers

  11. The radiation protection problems of high altitude and space flight

    Energy Technology Data Exchange (ETDEWEB)

    Fry, R.J.M.

    1993-04-01

    This paper considers the radiation environment in aircraft at high altitudes and spacecraft in low earth orbit and in deep space and the factors that influence the dose equivalents. Altitude, latitude and solar cycle are the major influences for flights below the radiation belts. In deep space, solar cycle and the occurrence of solar particle events are the factors of influence. The major radiation effects of concern are cancer and infertility in males. In high altitude aircraft the radiation consists mainly of protons and neutrons, with neutrons contributing about half the equivalent dose. The average dose rate at altitudes of transcontinental flights that approach the polar regions are greater by a factor of about 2.5 than on routes at low latitudes. Current estimates of does to air crews suggest they are well within the ICRP (1990) recommended dose limits for radiation workers.

  12. The radiation protection problems of high altitude and space flight

    Energy Technology Data Exchange (ETDEWEB)

    Fry, R.J.M.

    1993-01-01

    This paper considers the radiation environment in aircraft at high altitudes and spacecraft in low earth orbit and in deep space and the factors that influence the dose equivalents. Altitude, latitude and solar cycle are the major influences for flights below the radiation belts. In deep space, solar cycle and the occurrence of solar particle events are the factors of influence. The major radiation effects of concern are cancer and infertility in males. In high altitude aircraft the radiation consists mainly of protons and neutrons, with neutrons contributing about half the equivalent dose. The average dose rate at altitudes of transcontinental flights that approach the polar regions are greater by a factor of about 2.5 than on routes at low latitudes. Current estimates of does to air crews suggest they are well within the ICRP (1990) recommended dose limits for radiation workers.

  13. Canadian space agency discipline working group for space dosimetry and radiation science

    International Nuclear Information System (INIS)

    Waker, Anthony; Waller, Edward; Lewis, Brent; Bennett, Leslie; Conroy, Thomas

    2008-01-01

    Full text: One of the great technical challenges in the human and robotic exploration of space is the deleterious effect of radiation on humans and physical systems. The magnitude of this challenge is broadly understood in terms of the sources of radiation, however, a great deal remains to be done in the development of instrumentation, suitable for the space environment, which can provide real-time monitoring of the complex radiation fields encountered in space and a quantitative measure of potential biological risk. In order to meet these research requirements collaboration is needed between experimental nuclear instrumentation scientists, theoretical scientists working on numerical modeling techniques and radiation biologists. Under the auspices of the Canadian Space Agency such a collaborative body has been established as one of a number of Discipline Working Groups. Members of the Space Dosimetry and Radiation Science working group form a collaborative network across Canada including universities, government laboratories and the industrial sector. Three central activities form the core of the Space Dosimetry and Radiation Science DWG. An instrument sub-group is engaged in the development of instruments capable of gamma ray, energetic charged particle and neutron dosimetry including the ability to provide dosimetric information in real-time. A second sub-group is focused on computer modeling of space radiation fields in order to assess the performance of conceptual designs of detectors and dosimeters or the impact of radiation on cellular and sub-cellular biological targets and a third sub-group is engaged in the study of the biological effects of space radiation and the potential of biomarkers as a method of assessing radiation impact on humans. Many working group members are active in more than one sub-group facilitating communication throughout the whole network. A summary progress-report will be given of the activities of the Discipline Working Group and the

  14. Solid State Radiation Dosimeters for Space and Medical Applications

    Science.gov (United States)

    Buehler, Martin G. (Editor)

    1996-01-01

    This report describes the development of two radiation monitors (RADMON's) for use in detecting total radiation dose and high-energy particles. These radiation detectors are chip-size devices fabricated in 1.2 micrometer CMOS and have flown in space on both experimental and commercial spacecraft. They have been used to characterize protons and electrons in the Earth's radiation belts, particles from the Sun, and protons used for medical therapy. Having proven useful in a variety of applications, the detector is now being readied for commercialization.

  15. Natural Resources at Kennedy Space Center

    Science.gov (United States)

    Phillips, Lynne

    2015-01-01

    Informative presentation on the purpose and need for an Ecological Program at the Kennedy Space Center. Includes the federal laws mandating the program followed by a description of many of the long term monitoring projects. Projects include wildlife surveying by observation as well as interactive surveys to collect basic animal data for analysis of trends in habitat use and ecosystem health. The program is designed for a broad range in audience from elementary to college level.

  16. Recent measurements for hadrontherapy and space radiation: nuclear physics

    Science.gov (United States)

    Miller, J.

    2001-01-01

    The particles and energies commonly used for hadron therapy overlap the low end of the charge and energy range of greatest interest for space radiation applications, Z=1-26 and approximately 100-1000 MeV/nucleon. It has been known for some time that the nuclear interactions of the incident ions must be taken into account both in treatment planning and in understanding and addressing the effects of galactic cosmic ray ions on humans in space. Until relatively recently, most of the studies of nuclear fragmentation and transport in matter were driven by the interests of the nuclear physics and later, the hadron therapy communities. However, the experimental and theoretical methods and the accelerator facilities developed for use in heavy ion nuclear physics are directly applicable to radiotherapy and space radiation studies. I will briefly review relevant data taken recently at various accelerators, and discuss the implications of the measurements for radiotherapy, radiobiology and space radiation research.

  17. Applications of Radiative Heating for Space Exploration

    Science.gov (United States)

    Brandis, Aaron

    2017-01-01

    Vehicles entering planetary atmospheres at high speeds (6 - 12 kms) experience intense heating by flows with temperatures of the order 10 000K. The flow around the vehicle experiences significant dissociation and ionization and is characterized by thermal and chemical non-equilibrium near the shock front, relaxing toward equilibrium. Emission from the plasma is intense enough to impart a significant heat flux on the entering spacecraft, making it necessary to predict the magnitude of radiative heating. Shock tubes represent a unique method capable of characterizing these processes in a flight-similar environment. The Electric Arc Shock tube (EAST) facility is one of the only facilities in its class, able to produce hypersonic flows at speeds up to Mach 50. This talk will review the characterization of radiation measured in EAST with simulations by the codes DPLR and NEQAIR, and in particular, focus on the impact these analyses have on recent missions to explore the solar system.

  18. PAMELA Space Mission: The Transition Radiation Detector

    Science.gov (United States)

    Ambriola, M.; Bellotti, R.; Cafagna, F.; Circella, M.; De Marzo, C.; Giglietto, N.; Marangelli, B.; Mirizzi, N.; Romita, M.; Spinelli, P.

    2003-07-01

    PAMELA telescope is a satellite-b orne magnetic spectrometer built to fulfill the primary scientific objectives of detecting antiparticles (antiprotons and positrons) in the cosmic rays, and to measure spectra of particles in cosmic rays. The PAMELA telescope is currently under integration and is composed of: a silicon tracker housed in a permanent magnet, a time of flight and an anticoincidence system both made of plastic scintillators, a silicon imaging calorimeter, a neutron detector and a Transition Radiation Detector (TRD). The TRD detector is composed of 9 sensitive layers of straw tubes working in proportional mode for a total of 1024 channels. Each layer is interleaved with a radiator plane made of carbon fibers. The TRD detector characteristics will be described along with its performance studied exposing the detector to particle beams of electrons, pions, muons and protons of different momenta at both CERN-PS and CERN-SPS facilities.

  19. Exposure of the Spanish population to radiation from natural sources

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Talavera, M.; Suarez, E.; Matarranz, J.L.; Salas, R.; Ramos, L. [Consejo de Seguridad Nuclear. Justo Dorado, Madrid (Spain)

    2006-07-01

    We have assessed the exposure of the Spanish population to natural radiation sources. The annual average effective dose is estimated to be 2.38 mSv, taking into account contributions from cosmic radiation (13.8%), terrestrial gamma radiation (39%), radon and thoron inhalation (34%) and ingestion (13.2%). Cosmic radiation doses were calculated from town altitude data. Terrestrial gamma ray exposure outdoors was derived from the M.A.R.N.A. (natural gamma radiation map of Spain). Indoor gamma ray exposure was calculated by multiplying the corresponding outdoor value conversion factor, which was obtained by a linear least-squares fit of experimental measurements. Radon doses were estimated from national surveys carried out throughout the country. To assess doses by ingestion of water and foodstuffs we considered the results from a detailed study on consumption habits by age and geographical area in Spain, promoted by C.S.N., and average radioactivity values from UNSCEAR. (authors)

  20. Radiation energy devaluation in diffusion combusting flows of natural gas

    International Nuclear Information System (INIS)

    Makhanlall, Deodat; Munda, Josiah L.; Jiang, Peixue

    2013-01-01

    Abstract: CFD (Computational fluid dynamics) is used to evaluate the thermodynamic second-law effects of thermal radiation in turbulent diffusion natural gas flames. Radiative heat transfer processes in gas and at solid walls are identified as important causes of energy devaluation in the combusting flows. The thermodynamic role of thermal radiation cannot be neglected when compared to that of heat conduction and convection, mass diffusion, chemical reactions, and viscous dissipation. An energy devaluation number is also defined, with which the optimum fuel–air equivalence for combusting flows can be determined. The optimum fuel–air equivalence ratio for a natural gas flame is determined to be 0.7. The CFD model is validated against experimental measurements. - Highlights: • Thermodynamic effects of thermal radiation in combusting flows analyzed. • General equation for second-law analyses of combusting flows extended. • Optimum fuel–air equivalence ratio determined for natural gas flame

  1. Radiation Protection Studies of International Space Station Extravehicular Activity Space Suits

    Science.gov (United States)

    Cucinotta, Francis A. (Editor); Shavers, Mark R. (Editor); Saganti, Premkumar B. (Editor); Miller, Jack (Editor)

    2003-01-01

    This publication describes recent investigations that evaluate radiation shielding characteristics of NASA's and the Russian Space Agency's space suits. The introduction describes the suits and presents goals of several experiments performed with them. The first chapter provides background information about the dynamic radiation environment experienced at ISS and summarized radiation health and protection requirements for activities in low Earth orbit. Supporting studies report the development and application of a computer model of the EMU space suit and the difficulty of shielding EVA crewmembers from high-energy reentrant electrons, a previously unevaluated component of the space radiation environment. Chapters 2 through 6 describe experiments that evaluate the space suits' radiation shielding characteristics. Chapter 7 describes a study of the potential radiological health impact on EVA crewmembers of two virtually unexamined environmental sources of high-energy electrons-reentrant trapped electrons and atmospheric albedo or "splash" electrons. The radiological consequences of those sources have not been evaluated previously and, under closer scrutiny. A detailed computational model of the shielding distribution provided by components of the NASA astronauts' EMU is being developed for exposure evaluation studies. The model is introduced in Chapters 8 and 9 and used in Chapter 10 to investigate how trapped particle anisotropy impacts female organ doses during EVA. Chapter 11 presents a review of issues related to estimating skin cancer risk form space radiation. The final chapter contains conclusions about the protective qualities of the suit brought to light form these studies, as well as recommendations for future operational radiation protection.

  2. Development of radiation-curable resin based on natural rubber

    International Nuclear Information System (INIS)

    Dahlan Mohd; Abdul Ghani Harun

    1993-01-01

    A new radiation curable resin based on natural rubber has been developed. The resin was based on the reaction between low molecular weight epoxidised natural rubber and acrylic acid. When formulated with reactive monomers and photoinitiator, it solidified upon irradiation with UV light. The resin may find applications in coating for cellulosic-based substrates and pressure-sensitive adhesive

  3. Adaptation of radiation shielding code to space environment

    International Nuclear Information System (INIS)

    Okuno, Koichi; Hara, Akihisa

    1992-01-01

    Recently, the trend to the development of space has heightened. To the development of space, many problems are related, and as one of them, there is the protection from cosmic ray. The cosmic ray is the radiation having ultrahigh energy, and there was not the radiation shielding design code that copes with cosmic ray so far. Therefore, the high energy radiation shielding design code for accelerators was improved so as to cope with the peculiarity that cosmic ray possesses. Moreover, the calculation of the radiation dose equivalent rate in the moon base to which the countermeasures against cosmic ray were taken was simulated by using the improved code. As the important countermeasures for the safety protection from radiation, the covering with regolith is carried out, and the effect of regolith was confirmed by using the improved code. Galactic cosmic ray, solar flare particles, radiation belt, the adaptation of the radiation shielding code HERMES to space environment, the improvement of the three-dimensional hadron cascade code HETCKFA-2 and the electromagnetic cascade code EGS 4-KFA, and the cosmic ray simulation are reported. (K.I.)

  4. Modification of radiation damage by naturally occurring substances

    International Nuclear Information System (INIS)

    Prasad, K.N.

    1984-01-01

    The major objectives of studying the modification of radiation sensitivity have been (1) to identify a compound that will produce a differential protection or sensitization of the effect of irradiation on normal and tumor tissue, and (2) to understand more about the mechanisms of radiation damage. In spite of massive research on this particular problem since World War II, the first objective remains elusive. During this period, numerous radioprotective and radiosensitizing agents have been identified. These agents have served as important biologic tools for increasing our understanding of radiation injuries. Most of these substances are synthetic compounds and are very toxic to humans. In addition, very few of the compounds provide differential modifications of the effect of radiation on tumor and normal cells. This chapter presents objectives for identifying naturally occurring substances that modify the effect of x-radiation on mammalian cells and discusses the role of physiologic substances in modifying radiation injuries on mammalian normal and tumor cells

  5. Development of space foods using radiation technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju-Woon; Byun, Myung-Woo; Kim, Jae-Hun; Song, Beom-Suk; Choi, Jong-IL; Park, Jin-Kyu; Park, Jae-Nam; Han, In-Jun

    2008-07-15

    Four Korean food items (Kimchi, ready-to-eat fermented vegetable; Ramen, ready-to-cook noodles; Nutrition bar, ready-to-eat raw grain bar; Sujeonggwa, cinnamon beverage) have been developed as space foods by the application of high-dose gamma irradiation. All Korean space foods were certificated for use in space flight conditions during 30 days by the Russian Institute of Biomedical Problems. Establishment of research protocols on muscle atrophy mechanism using two-dimensional electrophoresis and various blotting analyses are conducted. And two bio-active molecules that potentially play an preventive role of muscle atrophy are uncovered. Integrative protocols linking between the effect of bio-active molecules and treadmill exercise for muscle atrophy inhibition are established. Reduction in body temperature and heartbeat rate were monitored after HIT injection to mice was conducted. Development of Korean astronaut preferred flavoring for space food was conducted to reduced atherogenic index (AI) than butter fat. The spread added honey and pineapple essence was preferred spreadability and overall flavor by sensory evaluation. Flavor was affected by irradiation source ({gamma}-ray or electron beam) or irradiation dosage (10, 20, 30, 40 and 50 kGy) using electronic nose system an space foods using gamma irradiation pH of porridge was mostly stable and pH increased. Most of TBARS value was generally low, and there wasn't any significant difference. Consistency, viscosity, and firmness was higher in round rice porridge and half rice porridge than in rice powder porridge, and increase in added water amount led to decrease of all textural properties.

  6. Development of space foods using radiation technology

    International Nuclear Information System (INIS)

    Lee, Ju-Woon; Byun, Myung-Woo; Kim, Jae-Hun; Song, Beom-Suk; Choi, Jong-IL; Park, Jin-Kyu; Park, Jae-Nam; Han, In-Jun

    2008-07-01

    Four Korean food items (Kimchi, ready-to-eat fermented vegetable; Ramen, ready-to-cook noodles; Nutrition bar, ready-to-eat raw grain bar; Sujeonggwa, cinnamon beverage) have been developed as space foods by the application of high-dose gamma irradiation. All Korean space foods were certificated for use in space flight conditions during 30 days by the Russian Institute of Biomedical Problems. Establishment of research protocols on muscle atrophy mechanism using two-dimensional electrophoresis and various blotting analyses are conducted. And two bio-active molecules that potentially play an preventive role of muscle atrophy are uncovered. Integrative protocols linking between the effect of bio-active molecules and treadmill exercise for muscle atrophy inhibition are established. Reduction in body temperature and heartbeat rate were monitored after HIT injection to mice was conducted. Development of Korean astronaut preferred flavoring for space food was conducted to reduced atherogenic index (AI) than butter fat. The spread added honey and pineapple essence was preferred spreadability and overall flavor by sensory evaluation. Flavor was affected by irradiation source (γ-ray or electron beam) or irradiation dosage (10, 20, 30, 40 and 50 kGy) using electronic nose system an space foods using gamma irradiation pH of porridge was mostly stable and pH increased. Most of TBARS value was generally low, and there wasn't any significant difference. Consistency, viscosity, and firmness was higher in round rice porridge and half rice porridge than in rice powder porridge, and increase in added water amount led to decrease of all textural properties

  7. Conformal nature of the Hawking radiation

    International Nuclear Information System (INIS)

    Materassi, M.

    2000-01-01

    String theory usually represents quantum black holes as systems whose statistical mechanics reproduces Hawking's thermodynamics in a very satisfactory way. Complicated brane theoretical models are worked out, as quantum versions of Supergravity solutions. These models are then assumed to be in thermal equilibrium: this is a little cheating, because one is looking for an explanation of the seeming thermodynamical nature of black holes, so they cannot be assumed to be finite temperature systems! In the model presented here, the black body spectrum arises with no statistical hypothesis as an approximation of the unitary evolution of microscopic black holes, which are always described by a 1+1 conformal field theory, characterized by some Virasoro algebra. At the end, one can state that the Hawking-thermodynamics of the system is a by-product of the algebraic Virasoro-symmetric nature of the event horizon. This is the central result of the present work. (author)

  8. Some comments on space flight and radiation limits

    International Nuclear Information System (INIS)

    Thornton, W.E.

    1997-01-01

    Setting limits on human exposure to space-related radiation involves two very different processes - the appropriate hard science, and certain emotional aspects and expectations of the groups involved. These groups include the general public and their elected politicians, the astronauts and flight crews, and NASA managers, each group with different expectations and concerns. Public and political views of human space flight and human radiation exposures are often poorly informed and are often based on emotional reactions to current events which may be distorted by 'experts' and the media. Career astronauts' and cosmonauts' views are much more realistic about the risks involved and there is a willingness on their part to accept increased necessary risks. However, there is a concern on their part about career-threatening dose limits, the potential for overexposures, and the health effects from all sources of radiation. There is special concern over radiation from medical studies. This last concern continues to raise the question of 'voluntary' participation in studies involving radiation exposure. There is greatly diversity in spaceflight crews and their expectations; and 'official' Astronaut Office positions will reflect strong management direction. NASA management has its own priorities and concerns and this fact will be reflected in their crucial influence on radiation limits. NASA, and especially spaceflight crews, might be best served by exposure limits which address all sources of spaceflight radiation and all potential effects from such exposure. radiation and all potential effects from such exposure

  9. PRELIMINARY DESIGN OF CRYOGENIC HYDROGEN RADIATION SHIELD FOR HUMAN SPACE FLIGHT

    Data.gov (United States)

    National Aeronautics and Space Administration — Hydrogen is the most mass-efficient radiation shielding material for protection against the space radiation environment. The concept of Cryogenic Hydrogen Radiation...

  10. Space Radiation and Exploration - Information for the Augustine Committee Review

    Science.gov (United States)

    Cucinotta, Francis; Semones, Edward; Kim, Myung-Hee; Jackson, Lori

    2009-01-01

    Space radiation presents significant health risks including mortality for Exploration missions: a) Galactic cosmic ray (GCR) heavy ions are distinct from radiation that occurs on Earth leading to different biological impacts. b) Large uncertainties in GCR risk projections impact ability to design and assess mitigation approaches and select crew. c) Solar Proton Events (SPEs) require new operational and shielding approaches and new biological data on risks. Risk estimates are changing as new scientific knowledge is gained: a) Research on biological effects of space radiation show qualitative and quantitative differences with X- or gamma-rays. b) Expert recommendations and regulatory policy are changing. c) New knowledge leads to changes in estimates for the number of days in space to stay below Permissible Exposure Limits (PELS).

  11. Review of Nuclear Physics Experiments for Space Radiation

    Science.gov (United States)

    Norbury, John W.; Miller, Jack; Adamczyk, Anne M.; Heilbronn, Lawrence H.; Townsend, Lawrence W.; Blattnig, Steve R.; Norman, Ryan B.; Guetersloh, Stephen B.; Zeitlin, Cary J.

    2011-01-01

    Human space flight requires protecting astronauts from the harmful effects of space radiation. The availability of measured nuclear cross section data needed for these studies is reviewed in the present paper. The energy range of interest for radiation protection is approximately 100 MeV/n to 10 GeV/n. The majority of data are for projectile fragmentation partial and total cross sections, including both charge changing and isotopic cross sections. The cross section data are organized into categories which include charge changing, elemental, isotopic for total, single and double differential with respect to momentum, energy and angle. Gaps in the data relevant to space radiation protection are discussed and recommendations for future experiments are made.

  12. Effects of space-relevant radiation on pre-osteoblasts

    International Nuclear Information System (INIS)

    Hu, Yueyuan

    2014-01-01

    Until now limited research has been conducted to address the mechanisms leading ionizing radiation exposure induced bone loss. This is relevant for cancer radiotherapy and human spaceflight. Exposure to radiation can result in elevated bone fracture risk in patients receiving cancer radiotherapy. In human spaceflight, astronauts are exposed to space radiation which is a very complex mixture consisting primarily of high-energy charged particles. Osteoblasts are of mesenchymal origin and responsible for creating and maintaining skeletal architecture; these cells produce extracellular matrix proteins and regulators of matrix mineralization during initial bone formation and later bone remodeling. The aim of this work was to investigate the effects of ionizing radiation on pre-osteoblasts including cellular survival, cell cycle regulation and differentiation modification. Experiments with the pre-osteoblast cell line OCT-1 and the mesenchymal stem cell line C3H10T1/2 showed that radiation cell killing depends on dose and linear energy transfer (LET) and is most effective at an LET of ∝150 keV/μm. High-LET radiation has a much more pronounced ability to induce cell cycle arrest in the G2/M phase. After both X-rays and heavy ions exposure, expression of the cell cycle regulator CDKN1A was significantly up-regulated in a dose-dependent manner. The findings suggest that cell cycle regulation is more sensitive to high-LET radiation than cell survival, which is not solely regulated through elevated CDKN1A expression. Radiation exposure enhances osteoblastic differentiation and maturation, and mediates Runx2 and TGF-β1 expression during early differentiation of pre-osteoblasts. Osteogenic differentiation did not alter cellular radiosensitivity, DNA repair of radiation-induced damages and the effects of radiation on proliferation. Further experiments are needed to elucidate possible synergistic effects of microgravity and radiation on osteoblast differentiation. This may

  13. Effects of space-relevant radiation on pre-osteoblasts

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yueyuan

    2014-02-12

    Until now limited research has been conducted to address the mechanisms leading ionizing radiation exposure induced bone loss. This is relevant for cancer radiotherapy and human spaceflight. Exposure to radiation can result in elevated bone fracture risk in patients receiving cancer radiotherapy. In human spaceflight, astronauts are exposed to space radiation which is a very complex mixture consisting primarily of high-energy charged particles. Osteoblasts are of mesenchymal origin and responsible for creating and maintaining skeletal architecture; these cells produce extracellular matrix proteins and regulators of matrix mineralization during initial bone formation and later bone remodeling. The aim of this work was to investigate the effects of ionizing radiation on pre-osteoblasts including cellular survival, cell cycle regulation and differentiation modification. Experiments with the pre-osteoblast cell line OCT-1 and the mesenchymal stem cell line C3H10T1/2 showed that radiation cell killing depends on dose and linear energy transfer (LET) and is most effective at an LET of ∝150 keV/μm. High-LET radiation has a much more pronounced ability to induce cell cycle arrest in the G2/M phase. After both X-rays and heavy ions exposure, expression of the cell cycle regulator CDKN1A was significantly up-regulated in a dose-dependent manner. The findings suggest that cell cycle regulation is more sensitive to high-LET radiation than cell survival, which is not solely regulated through elevated CDKN1A expression. Radiation exposure enhances osteoblastic differentiation and maturation, and mediates Runx2 and TGF-β1 expression during early differentiation of pre-osteoblasts. Osteogenic differentiation did not alter cellular radiosensitivity, DNA repair of radiation-induced damages and the effects of radiation on proliferation. Further experiments are needed to elucidate possible synergistic effects of microgravity and radiation on osteoblast differentiation. This may

  14. Natural background radiation and population dose distribution in India

    International Nuclear Information System (INIS)

    Nambi, K.S.V.; Bapat, V.N.; David, M.; Sundaram, V.K.; Sunta, C.M.; Soman, S.D.

    1986-01-01

    A country-wide survey of the outdoor natural background gamma radiation levels has been made using mailed thermoluminescent dosimeters (TLDs). The salient features of the results are: (1) The air-kerma levels and the population doses in various states follow log-normal and normal distributions respectively. (2) The national average value for the air dose (air-kerma) is 775 ± 370 (1σ)μGy/y. (3) The lowest air-kerma recorded is 0.23 mGy/y at Minicoy (Laccadive Islands) and the highest is 26.73 mGy/y at Chavra (monazite areas, Kerala). (4) There are significant temporal variation s (even as high as ± 40 per cent) of the background radiation level at many locations and at least in 10 locations where radon/thoron measurements are available, these could be associated with the seasonal variations in radon/thoron levels. (5) The mail control TLDs indicate a country-wide average value of 785 ± 225 μGy/y for the air-kerma which can be considered to provide a truly national average value for the natural background radiation level in India. (6) The mean natural radiation per caput for the country works out to be 690 ± 200 (1σ) Sv/y. (7) The natural radiation per caput seems to be maximum for Andhra Pradesh (1065 ± 325 μSv/y) and minimum for Maharashtra (370 ± 80 μSv/y). (8) The population dose from the external natural background radiation is estimated to be half a million person-Sievert. (9) Assuming 1 CRP risk factor, it can be estimated that just one out of the 43 cancer deaths occurring on an average per 100,000 population in India, can be attributed to the external natural background radiation. (author). 18 refs., 13 tabs., 9 figs

  15. Radiation processing of natural polymers: The IAEA contribution

    International Nuclear Information System (INIS)

    Haji-Saeid, Mohammad; Safrany, Agnes; Sampa, Maria Helena de O.; Ramamoorthy, Natesan

    2010-01-01

    Radiation processing offers a clean and additive-free method for preparation of value-added novel materials based on renewable, non-toxic, and biodegradable natural polymers. Crosslinked natural polymers can be used as hydrogel wound dressings, face cleaning cosmetic masks, adsorbents of toxins, and non-bedsore mats; while low molecular weight products show antibiotic, antioxidant, and plant-growth promoting properties. Recognizing the potential benefits that radiation technology can offer for processing of natural polymers into useful products, the IAEA implemented a coordinated research project (CRP) on 'Development of Radiation-processed products of Natural Polymers for application in Agriculture, Healthcare, Industry and Environment'. This CRP was launched at the end of 2007 with participation of 16 MS to help connecting radiation technology and end-users to derive enhanced benefits from these new value-added products of radiation-processed natural materials. In this paper the results of activities in participating MS related to this work will be presented.

  16. Radiation processing of natural polymers: The IAEA contribution

    Science.gov (United States)

    Haji-Saeid, Mohammad; Safrany, Agnes; Sampa, Maria Helena de O.; Ramamoorthy, Natesan

    2010-03-01

    Radiation processing offers a clean and additive-free method for preparation of value-added novel materials based on renewable, non-toxic, and biodegradable natural polymers. Crosslinked natural polymers can be used as hydrogel wound dressings, face cleaning cosmetic masks, adsorbents of toxins, and non-bedsore mats; while low molecular weight products show antibiotic, antioxidant, and plant-growth promoting properties. Recognizing the potential benefits that radiation technology can offer for processing of natural polymers into useful products, the IAEA implemented a coordinated research project (CRP) on "Development of Radiation-processed products of Natural Polymers for application in Agriculture, Healthcare, Industry and Environment". This CRP was launched at the end of 2007 with participation of 16 MS to help connecting radiation technology and end-users to derive enhanced benefits from these new value-added products of radiation-processed natural materials. In this paper the results of activities in participating MS related to this work will be presented.

  17. Radiation processing of natural polymers: The IAEA contribution

    Energy Technology Data Exchange (ETDEWEB)

    Haji-Saeid, Mohammad [Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Wagramer Strasse 5, A-1400 Vienna (Austria); Safrany, Agnes, E-mail: A.Safrany@iaea.or [Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Wagramer Strasse 5, A-1400 Vienna (Austria); Sampa, Maria Helena de O.; Ramamoorthy, Natesan [Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Wagramer Strasse 5, A-1400 Vienna (Austria)

    2010-03-15

    Radiation processing offers a clean and additive-free method for preparation of value-added novel materials based on renewable, non-toxic, and biodegradable natural polymers. Crosslinked natural polymers can be used as hydrogel wound dressings, face cleaning cosmetic masks, adsorbents of toxins, and non-bedsore mats; while low molecular weight products show antibiotic, antioxidant, and plant-growth promoting properties. Recognizing the potential benefits that radiation technology can offer for processing of natural polymers into useful products, the IAEA implemented a coordinated research project (CRP) on 'Development of Radiation-processed products of Natural Polymers for application in Agriculture, Healthcare, Industry and Environment'. This CRP was launched at the end of 2007 with participation of 16 MS to help connecting radiation technology and end-users to derive enhanced benefits from these new value-added products of radiation-processed natural materials. In this paper the results of activities in participating MS related to this work will be presented.

  18. Occupational exposure to natural radiation in Brazil

    International Nuclear Information System (INIS)

    Melo, D.R.

    2002-01-01

    The mining, milling and processing of uranium and thorium bearing minerals may result in radiation doses to workers. A preliminary survey pilot program, that included six mines in Brazil (two coal mines, one niobium mine, one nickel mine, one gold mine and one phosphate mine), was launched in order to determine the need to control the radioactive exposure of the mine-workers. Our survey consisted of the collection and analysis of urine samples, complemented by feces and air samples. The concentrations of uranium, thorium and polonium were measured in these samples and compared to background data from family members of the workers living in the same dwelling and from residents from the general population of Rio de Janeiro. The results from the coal mines indicated that the inhalation of radon progeny may be a source of occupational exposure. The workers from the nickel, gold and phosphate mines that were visited do not require a program to control internal radiological doses. The niobium mine results showed that in some areas of the industry exposure to thorium and uranium might occur. (author)

  19. Space Weather Effects in the Earth's Radiation Belts

    Science.gov (United States)

    Baker, D. N.; Erickson, P. J.; Fennell, J. F.; Foster, J. C.; Jaynes, A. N.; Verronen, P. T.

    2018-02-01

    The first major scientific discovery of the Space Age was that the Earth is enshrouded in toroids, or belts, of very high-energy magnetically trapped charged particles. Early observations of the radiation environment clearly indicated that the Van Allen belts could be delineated into an inner zone dominated by high-energy protons and an outer zone dominated by high-energy electrons. The energy distribution, spatial extent and particle species makeup of the Van Allen belts has been subsequently explored by several space missions. Recent observations by the NASA dual-spacecraft Van Allen Probes mission have revealed many novel properties of the radiation belts, especially for electrons at highly relativistic and ultra-relativistic kinetic energies. In this review we summarize the space weather impacts of the radiation belts. We demonstrate that many remarkable features of energetic particle changes are driven by strong solar and solar wind forcings. Recent comprehensive data show broadly and in many ways how high energy particles are accelerated, transported, and lost in the magnetosphere due to interplanetary shock wave interactions, coronal mass ejection impacts, and high-speed solar wind streams. We also discuss how radiation belt particles are intimately tied to other parts of the geospace system through atmosphere, ionosphere, and plasmasphere coupling. The new data have in many ways rewritten the textbooks about the radiation belts as a key space weather threat to human technological systems.

  20. Controlling criteria for radiation exposure of astronauts and space workers

    International Nuclear Information System (INIS)

    Katoh, Kazuaki

    1989-01-01

    Space workers likely to suffer from radiation exposure in the outer space are currently limited to the U.S. and Soviet Union, and only a small amount of data and information is available concerning the techniques and criteria for control of radiation exposure in this field. Criteria used in the Soviet Union are described first. The criteria (TRS-75), called the Radiation Safety Criteria for Space Navigation, are tentative ones set up in 1975. They are based on risk assessment. The standard radiation levels are established based on unit flight time: 50rem for 1 month, 80rem for 3 months, 110rem for 6 months and 150rem for 12 months. These are largely different from the emergency exposure limit of 100mSv (10rem) specified in a Japanese law, and the standard annual exposure value of 50mSv (5rem) for workers in nuclear power plants at normal times. For the U.S., J.A. Angelo, Jr., presented a paper titled 'Radiation Protection Issues and Techniques concerning Extended Manned Space Missions' at an IAEA meeting held in 1988. Though the criteria shown in the paper are not formal ones at the national level, similar criteria are expected to be adopted by the nation in the near future. The exposure limits recommended in the paper include a depth dose of 1-4Sv for the whole life span of a worker. (Nogami, K.)

  1. BioSentinel: Developing a Space Radiation Biosensor

    Science.gov (United States)

    Santa Maria, Sergio R.

    2015-01-01

    BioSentinel is an autonomous fully self-contained science mission that will conduct the first study of the biological response to space radiation outside low Earth orbit (LEO) in over 40 years. The 4-unit (4U) BioSentinel biosensor system, is housed within a 6-Unit (6U) spacecraft, and uses yeast cells in multiple independent microfluidic cards to detect and measure DNA damage that occurs in response to ambient space radiation. Cell growth and metabolic activity will be measured using a 3-color LED detection system and a metabolic indicator dye with a dedicated thermal control system per fluidic card.

  2. High-Performance, Radiation-Hardened Electronics for Space Environments

    Science.gov (United States)

    Keys, Andrew S.; Watson, Michael D.; Frazier, Donald O.; Adams, James H.; Johnson, Michael A.; Kolawa, Elizabeth A.

    2007-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project endeavors to advance the current state-of-the-art in high-performance, radiation-hardened electronics and processors, ensuring successful performance of space systems required to operate within extreme radiation and temperature environments. Because RHESE is a project within the Exploration Technology Development Program (ETDP), RHESE's primary customers will be the human and robotic missions being developed by NASA's Exploration Systems Mission Directorate (ESMD) in partial fulfillment of the Vision for Space Exploration. Benefits are also anticipated for NASA's science missions to planetary and deep-space destinations. As a technology development effort, RHESE provides a broad-scoped, full spectrum of approaches to environmentally harden space electronics, including new materials, advanced design processes, reconfigurable hardware techniques, and software modeling of the radiation environment. The RHESE sub-project tasks are: SelfReconfigurable Electronics for Extreme Environments, Radiation Effects Predictive Modeling, Radiation Hardened Memory, Single Event Effects (SEE) Immune Reconfigurable Field Programmable Gate Array (FPGA) (SIRF), Radiation Hardening by Software, Radiation Hardened High Performance Processors (HPP), Reconfigurable Computing, Low Temperature Tolerant MEMS by Design, and Silicon-Germanium (SiGe) Integrated Electronics for Extreme Environments. These nine sub-project tasks are managed by technical leads as located across five different NASA field centers, including Ames Research Center, Goddard Space Flight Center, the Jet Propulsion Laboratory, Langley Research Center, and Marshall Space Flight Center. The overall RHESE integrated project management responsibility resides with NASA's Marshall Space Flight Center (MSFC). Initial technology development emphasis within RHESE focuses on the hardening of Field Programmable Gate Arrays (FPGA)s and Field Programmable Analog

  3. Measurement of natural background radiation intensity on a train.

    Science.gov (United States)

    Chen, Yen-Fu; Lin, Jeng-Wei; Sheu, Rong-Jiun; Lin, Uei-Tyng; Jiang, Shiang-Huei

    2011-03-01

    This work aims to measure different components of natural background radiation on a train. A radiation measurement system consisting of four types of radiation detectors, namely, a Berkeley Lab cosmic-ray detector, moderated (3)He detector, high-pressure ionisation chamber and NaI(Tl) spectrometer, associated with a global positioning system unit was established for this purpose. For the commissioning of the system, a test measurement on a train along the railway around the northern Taiwan coast from Hsinchu to Hualien with a distance of ∼ 275 km was carried out. No significant variation of the intensities of the different components of natural background radiation was observed, except when the train went underground or in the tunnels. The average external dose rate received by the crew of the train was estimated to be 62 nSv h(-1).

  4. Measurement of natural background radiation intensity on a train

    International Nuclear Information System (INIS)

    Chen, Y. F.; Lin, J. W.; Sheu, R. J.; Lin, U. T.; Jiang, S. H.

    2011-01-01

    This work aims to measure different components of natural background radiation on a train. A radiation measurement system consisting of four types of radiation detectors, namely, a Berkeley Lab cosmic-ray detector, moderated 3He detector, high pressure ionisation chamber and NaI(Tl) spectrometer, associated with a global positioning system unit was established for this purpose. For the commissioning of the system, a test measurement on a train along the railway around the northern Taiwan coast from Hsinchu to Hualien with a distance of ∼275 km was carried out. No significant variation of the intensities of the different components of natural background radiation was observed, except when the train went underground or in the tunnels. The average external dose rate received by the crew of the train was estimated to be 62 nSv h -1 . (authors)

  5. Lightweight space radiator with leakage control by internal electrostatic fields

    International Nuclear Information System (INIS)

    Kim, H.; Bankoff, S.G.; Miksis, M.J.

    1991-01-01

    An electrostatic liquid film space radiator is proposed. This will employ an internal electrostatic field to prevent leakage of the liquid-metal coolant out of a puncture. This overcomes the major disadvantage of membrane radiators, which is their vulnerability to micrometeorite impacts. Calculations show that leaks of liquid lithium at 700 degree K can easily be stopped from punctures which are several mm in diameter, with very large safety factors. The basic idea lends itself to a variety of radiator concepts, both rotating and non-rotating. Some typical film thickness and pressure calculations in the presence of an electric field are shown

  6. Gamma radiation in ceramic capacitors: a study for space missions

    Science.gov (United States)

    dos Santos Ferreira, Eduardo; Sarango Souza, Juliana

    2017-10-01

    We studied the real time effects of the gamma radiation in ceramic capacitors, in order to evaluate the effects of cosmic radiation on these devices. Space missions have electronic circuits with various types of devices, many studies have been done on semiconductor devices exposed to gamma radiation, but almost no studies for passive components, in particular ceramic capacitors. Commercially sold ceramic capacitors were exposed to gamma radiation, and the capacitance was measured before and after exposure. The results clearly show that the capacitance decreases with exposure to gamma radiation. We confirmed this observation in a real time capacitance measurement, obtained using a data logging system developed by us using the open source Arduino platform.

  7. Electromagnetic radiation in a semi-compact space

    Science.gov (United States)

    Iso, Satoshi; Kitazawa, Noriaki; Yokoo, Sumito

    2018-02-01

    In this note, we investigate the electromagnetic radiation emitted from a revolving point charge in a compact space. If the point charge is circulating with an angular frequency ω0 on the (x , y)-plane at z = 0 with boundary conditions, x ∼ x + 2 πR and y ∼ y + 2 πR, it emits radiation into the z-direction of z ∈ [ - ∞ , + ∞ ]. We find that the radiation shows discontinuities as a function of ω0 R at which a new propagating mode with a different Fourier component appears. For a small radius limit ω0 R ≪ 1, all the Fourier modes except the zero mode on (x , y)-plane are killed, but an effect of squeezing the electric field totally enhances the radiation. In the large volume limit ω0 R → ∞, the energy flux of the radiation reduces to the expected Larmor formula.

  8. Natural and anthropogeneous radiation in the Erzgebirge: Risk factor radon

    International Nuclear Information System (INIS)

    Jacobi, W.

    1992-01-01

    The geological formations in the saxoinian-thuringian low mountain range contain rocks with a relatively high share of uranium ( 238 U) and its follow-up product radium ( 226 Ra). Independent of mining this results in increased radiation levels to which the local population has always been exposed. Natural radiation levels may, of course, vary strongly from one location to the next and therefore human exposure varies accordingly. (orig.) [de

  9. ISS and Space Shuttle Radiation Measurements at Solar Minimum

    Science.gov (United States)

    Gaza, Ramona; Welton, Andrew; Dunegan, Audrey; Lee, Kerry

    2011-01-01

    A summary of 2008-2011 ISS and Space Shuttle radiation dosimetry results for inside vehicle radiation monitoring in low-Earth orbit will be presented. Results include new data from ISS Expedition 22-25/20A radiation area monitors (RAM) and Shuttle Missions STS127-STS133 passive radiation dosimeters (PRD). ISS 20A radiation measurement locations included three Node 2 crew quarters locations at NOD2S5_CQ, NOD2P5_CQ and CQ-3 (Deck), as well as ESA Columbus, and JAXA Kibo locations. ISS 20A and STS127-STS133 missions were flown at 51.6 inclination with an altitude range of 330-350 km. The passive radiation results will be presented in terms of measured daily dose obtained using luminescence detectors (i.e., Al2O3:C, LiF:Mg,Ti and CaF2:Tm). In addition, preliminary results from the DOSIS 2 Project, in collaboration with the German Space Agency (DLR) will be presented. SRAG s participation to the DOSIS 2 exposure on ISS (11/16/2009-05/26/2010) involved passive radiation measurements at 10 different shielding locations inside the ESA Columbus Module.

  10. Study on biological response to space radiation and its countermeasure

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong Il; Lee, Ju Woon; Kim, Dong Ho; Kim, Jae Hun; Song, Beom Suk; Kim, Jae Kyung; Park, Jong Heum; Kim, Jin Kyu [KAERI, Daejeon (Korea, Republic of)

    2011-12-15

    The purpose is to develop the core technologies for the advanced life supporting system based on radiation technology by 2015 and to be a member of G7 in the space technology research field. And it is the final aim that contribution for establishment of the self-supporting technology and national strength by 2020. To simulate the space environment of microgravity and expose to space radiation, denervation model was established in Gamma Phytotron. The changes in microflora population in animal model was shown. The effect of simulated microgravity and long-term exposure to irradiation was investigated. In the experiment of MARS 500, crews for expedition to Mars had been served by Korean space foods (Bulgogi, Bibimbap, Seaweed soup, Mulberry beverage, Kimchi, Sujeonggwa) for 120 days, then their immunity will be examined and compared with it on the ground.

  11. Study on biological response to space radiation and its countermeasure

    International Nuclear Information System (INIS)

    Choi, Jong Il; Lee, Ju Woon; Kim, Dong Ho; Kim, Jae Hun; Song, Beom Suk; Kim, Jae Kyung; Park, Jong Heum; Kim, Jin Kyu

    2011-12-01

    The purpose is to develop the core technologies for the advanced life supporting system based on radiation technology by 2015 and to be a member of G7 in the space technology research field. And it is the final aim that contribution for establishment of the self-supporting technology and national strength by 2020. To simulate the space environment of microgravity and expose to space radiation, denervation model was established in Gamma Phytotron. The changes in microflora population in animal model was shown. The effect of simulated microgravity and long-term exposure to irradiation was investigated. In the experiment of MARS 500, crews for expedition to Mars had been served by Korean space foods (Bulgogi, Bibimbap, Seaweed soup, Mulberry beverage, Kimchi, Sujeonggwa) for 120 days, then their immunity will be examined and compared with it on the ground

  12. Synergistic effects of space radiation and microgravity (miRNA WT and ced-1 mutant)

    Data.gov (United States)

    National Aeronautics and Space Administration — Space radiations and microgravity both could cause DNA damage in cells but the effects of microgravity on DNA damage response to space radiations are still...

  13. Synergistic effects of space radiation and microgravity (miRNA WT and dys-mutant)

    Data.gov (United States)

    National Aeronautics and Space Administration — Space radiations and microgravity both could cause DNA damage in cells but the effects of microgravity on DNA damage response to space radiations are still...

  14. Using the FLUKA Monte Carlo Code to Simulate the Interactions of Ionizing Radiation with Matter to Assist and Aid Our Understanding of Ground Based Accelerator Testing, Space Hardware Design, and Secondary Space Radiation Environments

    Science.gov (United States)

    Reddell, Brandon

    2015-01-01

    Designing hardware to operate in the space radiation environment is a very difficult and costly activity. Ground based particle accelerators can be used to test for exposure to the radiation environment, one species at a time, however, the actual space environment cannot be duplicated because of the range of energies and isotropic nature of space radiation. The FLUKA Monte Carlo code is an integrated physics package based at CERN that has been under development for the last 40+ years and includes the most up-to-date fundamental physics theory and particle physics data. This work presents an overview of FLUKA and how it has been used in conjunction with ground based radiation testing for NASA and improve our understanding of secondary particle environments resulting from the interaction of space radiation with matter.

  15. Thermal annealing of natural, radiation-damaged pyrochlore

    Energy Technology Data Exchange (ETDEWEB)

    Zietlow, Peter; Beirau, Tobias; Mihailova, Boriana; Groat, Lee A.; Chudy, Thomas; Shelyug, Anna; Navrotsky, Alexandra; Ewing, Rodney C.; Schlüter, Jochen; Škoda, Radek; Bismayer, Ulrich

    2017-01-01

    Abstract

    Radiation damage in minerals is caused by the α-decay of incorporated radionuclides, such as U and Th and their decay products. The effect of thermal annealing (400–1000 K) on radiation-damaged pyrochlores has been investigated by Raman scattering, X-ray powder diffraction (XRD), and combined differential scanning calorimetry/thermogravimetry (DSC/TG). The analysis of three natural radiation-damaged pyrochlore samples from Miass/Russia [6.4 wt% Th, 23.1·10

  16. The space as a natural laboratory of Electrotechnics

    Directory of Open Access Journals (Sweden)

    P. K. Marhavilas

    2008-01-01

    Full Text Available Electricity is a general term for a variety of phenomena resulting from the presence and flow of charge, and “Electro-technics” is the study or the science of practical and industrial applications of electricity. On the other side, the space is mainly characterized by the interaction of energetic charged particles with electric and magnetic fields, which justifies the claim «the space composes a natural laboratory of electrotechnics». This paper reviews present understanding of the dy-namics of the solar-terrestrial environment, and its impacts on the human activity, and explain processes, which establish the space as a natural laboratory of electrotechnics.

  17. Micronuclei frequency in albino rats exposed to high natural radiation

    International Nuclear Information System (INIS)

    Aneesh, D.; Godwin Wesley, S.

    2013-01-01

    Genotoxicity and DNA damage endpoints are used to evaluate results in the context of cell survival. Genotoxicity in mammalian cells is monitored mostly by using cytokinesis-block micronucleus (CBMN) assay. The score of micronuclei (MN) in peripheral blood lymphocytes can be used as a biomarker and also as a bio-dosimeter of radiation exposure. In the present study the effect of natural radiation on albino rats has been investigated, to find out if there is any increase in MN frequency in peripheral blood lymphocytes. Animals at the age of 2-3 weeks were exposed to natural radiation, at the dose of 10.38 μGyh -1 for a period of 6 months. A parallel control set was also maintained (0.12 μGy h -1 '). Blood samples were collected from both test (exposed to natural radiation) and control rats. Lymphocyte culture was done following 'microculture techniques' for 72 h. Cytochalasin B, at a concentration of 6.0 μg/ml, was added to the lymphocyte cultures at 44 h to block cytokinesis. The frequency of MN was evaluated by scoring a total of 1000 binucleated (BN) cells from one slide. The frequency of MN among the rats exposed to natural radiation was found to be 1.83±0.05 per 1000 BN cells and in the control it was 1.82±0.07 per 1000 BN cells. No statistically significant difference in the MN frequencies of exposed and control groups (p>0.05) was seen. The lower MN frequency in natural radiation exposed rats could be an indication of adaptive response. (author)

  18. NASA Space Radiation Risk Project: Overview and Recent Results

    Science.gov (United States)

    Blattnig, Steve R.; Chappell, Lori J.; George, Kerry A.; Hada, Megumi; Hu, Shaowen; Kidane, Yared H.; Kim, Myung-Hee Y.; Kovyrshina, Tatiana; Norman, Ryan B.; Nounu, Hatem N.; hide

    2015-01-01

    The NASA Space Radiation Risk project is responsible for integrating new experimental and computational results into models to predict risk of cancer and acute radiation syndrome (ARS) for use in mission planning and systems design, as well as current space operations. The project has several parallel efforts focused on proving NASA's radiation risk projection capability in both the near and long term. This presentation will give an overview, with select results from these efforts including the following topics: verification, validation, and streamlining the transition of models to use in decision making; relative biological effectiveness and dose rate effect estimation using a combination of stochastic track structure simulations, DNA damage model calculations and experimental data; ARS model improvements; pathway analysis from gene expression data sets; solar particle event probabilistic exposure calculation including correlated uncertainties for use in design optimization.

  19. Natural Radiation in byproducts of the production of phosphoric acid

    International Nuclear Information System (INIS)

    Silveira, Marcilei A. Guazzelli da; Cardoso, L.L.; Medina, N.H.

    2014-01-01

    Natural radiation is the largest source of radiation exposure to which man is subject. It is formed basically by cosmic radiation and the radionuclides present in the Earth crust, as 40 K and the elements of the decay series of 232 Th and 238 U. Phosphate ores, which constitutes the raw material for the production of phosphoric acid, have a high rate of natural radiation from the decay series of 232 Th and 238 U. Phosphogypsum, which is naturally radioactivity, is a by-product of the production of phosphoric acid by the wet method. For each ton of phosphoric acid it is produced about 4.5 tons of phosphogypsum. This work presents the analysis of samples collected in all stages of the manufacturing process of phosphoric acid, which generates the phosphogypsum. Gamma-ray spectrometry was used to measure the concentration of the elements of the decay series of 232 Th and 238 U. All analyzed samples showed a high concentration of radionuclides, promoting the need for further steps in the process in order to reduce the presence of such radionuclides in the phosphogypsum. The results indicate the radionuclide 238 U has higher contribution in some samples of the intermediate stages of the process. All samples exceeded the international average range of human exposure to terrestrial gamma radiation, which is 0.3 to 1.0 mSv/year. (author)

  20. Management of radiation injuries by natural herbs and neutraceuticals

    International Nuclear Information System (INIS)

    Goyal, P.K.

    2013-01-01

    In the era of expanding nuclear energy program all over world, the role of radiation biology has acquired greater relevance and significance in addressing the health and environment issues. In view of constant human exposure to background radiation both naturally and man made e.g nuclear power plants and weapons testing, consumer products, medical X-ray, uranium mining and milling etc., the radiobiological research has been devoted to induction of cancer and evaluation of genetic effects. In the present time, nuclear terrorism and weapon related effects are raising much alarm and concern to public health. Obviously, radiation biology research has great potential in diagnosis, therapy and establishing standards for assessment risk from radiation exposure. The development of effective medical countermeasures to protect, mitigate, and treat normal tissue injury needs urgent investigation for basic molecular mechanisms and developing appropriate ready to-use kits using relevant cellular, animal model and clinical trails for practical purposes. Since the use of synthetic compounds is associated with the inherent toxicity, attention in recent years has been directed towards developing radiation countermeasure agents from the natural sources and/or nature-identical molecules. The rich biodiversity available in the Indian subcontinent has yielded several new drugs that find application in the modern medicine and there is a like hood of discovering many more, Over the last few years, interest in evaluating oriental medicinal herbs and edible phyto products for the use in anti-radiation strategies is encouraging and emerging as an acceptable approach for preventing the radiation induced lesions in many countries. Several Indian medicinal plants (Emblica officinalis, Rosemarinus officinalis, Trigonella foenum-graecum, Alstonia scholaris, Tinospora cordifolia, Phyllanthus niruri, Svzvgiumcumini, Aegle marmelos etc) and antioxidant vitamins (C and E) have been tested in this

  1. Some technologically enhanced exposures to natural radiation environment in India

    International Nuclear Information System (INIS)

    Lalit, B.Y.; Shukla, V.K.; Ramachandran, T.V.; Mishra, U.C.

    1982-01-01

    A summary of results of gamma spectrometric measurements of natural radioactivity in a number of coal and flyash samples from thermal power plants and phosphatic fertilizer samples collected from various fertilizer plants in India are presented. These constitute the sources of technologically enhanced exposures to natural radiation. A brief description of sampling and measurement procedures is given. The radiation doses to the population from coal burning for electricity generation have been calculated using the method outlined in UNSCEAR report of 1979 with corrections for local population density. The external radiation dose to the farmers has been calculated on the basis of usage of phosphatic fertilizers for rice, wheat, millets and sugarcane crops for the normal agricultural practices

  2. Nature and magnitude of the problem of spent radiation sources

    International Nuclear Information System (INIS)

    1991-09-01

    Various types of sealed radiation sources are widely used in industry, medicine and research. Virtually all countries have some sealed sources. The activity in the sources varies from kilobecquerels in consumer products to hundreds of pentabecquerels in facilities for food irradiation. Loss or misuse of sealed sources can give rise to accidents resulting in radiation exposure of workers and members of the general public, and can also give rise to extensive contamination of land, equipment and buildings. In extreme cases the exposure can be lethal. Problems of safety relating to spent radiation sources have been under consideration within the Agency for some years. The first objective of the project has been to prepare a comprehensive report reviewing the nature and background of the problem, also giving an overview of existing practices for the management of spent radiation sources. This report is the fulfilment of this first objective. The safe management of spent radiation sources cannot be studied in isolation from their normal use, so it has been necessary to include some details which are relevant to the use of radiation sources in general, although that area is outside the scope of this report. The report is limited to radiation sources made up of radioactive material. The Agency is implementing a comprehensive action plan for assistance to Member States, especially the developing countries, in all aspects of the safe management of spent radiation sources. The Agency is further seeking to establish regional or global solutions to the problems of long-term storage of spent radiation sources, as well as finding routes for the disposal of sources when it is not feasible to set up safe national solutions. The cost of remedial actions after an accident with radiation sources can be very high indeed: millions of dollars. If the Agency can help to prevent even one such single accident, the cost of its whole programme in this field would be more than covered. Refs

  3. Natural sources of radiation exposure and the teaching of radioecology

    International Nuclear Information System (INIS)

    Anjos, R M; Veiga, R; Carvalho, C; Sanches, N; Estellita, L; Macario, K; Zanuto, P; Queiroz, E

    2008-01-01

    We have developed an experimental activity that introduces concepts of the natural ionizing radiation and its interaction with our contemporary environment that can be used with students from secondary to college level. The experiment is based on the use of traditional and cheap portable Geiger–Müller detectors as survey meters for in situ measurements

  4. Human genetic studies in areas of high natural radiation

    International Nuclear Information System (INIS)

    Freire-Maia, A.; Krieger, H.

    1978-01-01

    Data have been obtained by a genetic-epidemiological survey of a population living in the State of Espirito Santo (Brazil), and subjected to mean levels of natural radiation, per locality, ranging from 7 to 133 μrad/hr. Multiple regression models have been applied to the data, and the results showed no detectable effect of natural radiation on the sex ratio at birth, on the occurrence of congenital anomalies, and on the numbers of pregnancy terminations, stillbirths, livebirths, and post-infant mortality in the children, as well as fecundity and fertility of the couples (these observations contradict some data from the literature, based on official records and without analyses of the concomitant effects of other variables). However, nonsignificant results cannot be considered as disproving harmful effects of natural radiation on mortality and morbidity. These results may simply mean that other causes of mortality and morbidity are so important, under the conditions of the study, that the contribution of low-level, chronic natural radiation is made negligible. (author)

  5. Towards Space Exploration of Moon, Mars Neos: Radiation Biological Basis

    Science.gov (United States)

    Hellweg, Christine; Baumstark-Khan, Christa; Berger, Thomas; Reitz, Guenther

    2016-07-01

    Radiation has emerged as the most critical issue to be resolved for long-term missions both orbital and interplanetary. Astronauts are constantly exposed to galactic cosmic radiation (GCR) of various energies with a low dose rate. Primarily late tissue sequels like genetic alterations, cancer and non-cancer effects, i.e. cataracts and degenerative diseases of e.g. the central nervous system or the cardiovascular system, are the potential risks. Cataracts were observed to occur earlier and more often in astronauts exposed to higher proportions of galactic ions (Cucinotta et al., 2001). Predictions of cancer risk and acceptable radiation exposure in space are subject to many uncertainties including the relative biological effectiveness (RBE) of space radiation especially heavy ions, dose-rate effects and possible interaction with microgravity and other spaceflight environmental factors. The initial cellular response to radiation exposure paves the way to late sequelae and starts with damage to the DNA which complexity depends on the linear energy transfer (LET) of the radiation. Repair of such complex DNA damage is more challenging and requires more time than the repair of simple DNA double strand breaks (DSB) which can be visualized by immunofluorescence staining of the phosphorylated histone 2AX (γH2AX) and might explain the observed prolonged cell cycle arrests induced by high-LET in comparison to low-LET irradiation. Unrepaired or mis-repaired DNA DSB are proposed to be responsible for cell death, mutations, chromosomal aberrations and oncogenic cell transformation. Cell killing and mutation induction are most efficient in an LET range of 90-200 keV/µm. Also the activation of transcription factors such as Nuclear Factor κB (NF-κB) and gene expression shaping the cellular radiation response depend on the LET with a peak RBE between 90 and 300 keV/µm. Such LET-RBE relationships were observed for cataract and cancer induction by heavy ions in laboratory animals

  6. Biological effects of space radiation and development of effective countermeasures

    Science.gov (United States)

    Kennedy, Ann R.

    2014-04-01

    As part of a program to assess the adverse biological effects expected from astronauts' exposure to space radiation, numerous different biological effects relating to astronauts' health have been evaluated. There has been major focus recently on the assessment of risks related to exposure to solar particle event (SPE) radiation. The effects related to various types of space radiation exposure that have been evaluated are: gene expression changes (primarily associated with programmed cell death and extracellular matrix (ECM) remodeling), oxidative stress, gastrointestinal tract bacterial translocation and immune system activation, peripheral hematopoietic cell counts, emesis, blood coagulation, skin, behavior/fatigue (including social exploration, submaximal exercise treadmill and spontaneous locomotor activity), heart functions, alterations in biological endpoints related to astronauts' vision problems (lumbar puncture/intracranial pressure, ocular ultrasound and histopathology studies), and survival, as well as long-term effects such as cancer and cataract development. A number of different countermeasures have been identified that can potentially mitigate or prevent the adverse biological effects resulting from exposure to space radiation.

  7. Persistence of Space Radiation Induced Cytogenetic Damage in the Blood Lymphocytes of Astronauts

    Science.gov (United States)

    George, Kerry

    Cytogenetic damage in astronaut's peripheral blood lymphocytes is a useful in vivo marker of space radiation induced damage. Moreover, if radiation induced chromosome translocations persist in peripheral blood lymphocytes for many years, as has been assumed, they could potentially be used to measure retrospective doses or prolonged low dose rate exposures. However, as more data becomes available, evidence suggests that the yield of translocations may decline with time after irradiation, at least for space radiation exposures. We present our latest follow-up measurements of chromosome aberrations in astronauts' blood lymphocytes assessed by FISH painting and collected at various times beginning directly after return from space to several years after flight. For most individuals the analysis of individual time-courses for translocations revealed a temporal decline of yields with different half-lives. Since the level of stable aberrations depends on the interplay between natural loss of circulating T-lymphocytes and replenishment from the stem or progenitor cells, the differences in the rates of decay could be explained by inter-individual variation in lymphocyte turn over. Biodosimetry estimates derived from cytogenetic analysis of samples collected a few days after return to earth lie within the range expected from physical dosimetry. However, a temporal decline in yields may indicate complications with the use of stable aberrations for retrospective dose reconstruction, and the differences in the decay time may reflect individual variability in risk from space radiation exposure. In addition, limited data on multiple flights show a lack of correlation between time in space and translocation yields. Data from one crewmember who has participated in two separate long-duration space missions and has been followed up for over 10 years provide limited information on the effect of repeat flights and show a possible adaptive response to space radiation exposure.

  8. NASA Self-Assessment of Space Radiation Research

    Science.gov (United States)

    Cucinotta, Francis A.

    2010-01-01

    Space exploration involves unavoidable exposures to high-energy galactic cosmic rays whose penetration power and associated secondary radiation makes radiation shielding ineffective and cost prohibitive. NASA recognizing the possible health dangers from cosmic rays notified the U.S. Congress as early as 1959 of the need for a dedicated heavy ion accelerator to study the largely unknown biological effects of galactic cosmic rays on astronauts. Information and scientific tools to study radiation health effects expanded over the new decades as NASA exploration programs to the moon and preparations for Mars exploration were carried out. In the 1970 s through the early 1990 s a more than 3-fold increase over earlier estimates of fatal cancer risks from gamma-rays, and new knowledge of the biological dangers of high LET radiation were obtained. Other research has increased concern for degenerative risks to the central nervous system and other tissues at lower doses compared to earlier estimates. In 1996 a review by the National Academy of Sciences Space Science Board re-iterated the need for a dedicated ground-based accelerator facility capable of providing up to 2000 research hours per year to reduce uncertainties in risks projections and develop effective mitigation measures. In 1998 NASA appropriated funds for construction of a dedicated research facility and the NASA Space Radiation Laboratory (NSRL) opened for research in October of 2003. This year marks the 8th year of NSRL research were about 1000 research hours per year have been utilized. In anticipation of the approaching ten year milestone, funded investigators and selected others are invited to participate in a critical self-assessment of NSRL research progress towards NASA s goals in space radiation research. A Blue and Red Team Assessment format has been integrated into meeting posters and special plenary sessions to allow for a critical debate on the progress of the research and major gaps areas. Blue

  9. Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects

    Science.gov (United States)

    Kennedy, Ann

    The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and observed that a mixture of antioxidants (AOX), containing L-selenomethionine, N-acetyl cysteine (NAC), ascorbic acid, vitamin E succinate, and alpha-lipoic acid, is highly effective at reducing space radiation induced oxidative stress in both in vivo and in vitro systems, space radiation induced cytotoxicity and malignant transformation in vitro [1-7]. In studies designed to determine whether the AOX formulation could affect radiation induced mortality [8], it was observed that the AOX dietary supplement increased the 30-day survival of ICR male mice following exposure to a potentially lethal dose (8 Gy) of X-rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 hours following exposure to doses of 1 Gy and 8 Gy. Antioxidant treatment also resulted in increased bone marrow cell counts following irradiation, and prevented peripheral lymphopenia following 1 Gy irradiation. Supplementation with antioxidants in irradiated animals resulted in several gene expression changes: the antioxidant treatment was associated with increased Bcl-2, and decreased Bax, caspase-9 and TGF-β1 mRNA expression in the bone marrow following irradiation. These results suggest that modulation of apoptosis may be mechanistically involved in hematopoietic system radioprotection by antioxidants. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow following sub-lethal or potentially lethal irradiation. Taken together

  10. Radiation protection at workplaces with increased natural radiation exposure in Greece: recording, monitoring and protection measures

    International Nuclear Information System (INIS)

    Potiriadis, C.; Koukoliou, V.

    2002-01-01

    Greek Atomic Energy Commission (GAEC) is the regulatory, advisory and competent authority on radiation protection matters. It is the authority responsible for the introduction of Radiation Protection regulations and monitoring of their implementation. In 1997, within the frame of its responsibilities the Board of the GAEC appointed a task group of experts to revise and bring the present Radiation Protection Regulations into line with the Basic Safety Standards (BSS) 96/29/Euratom Directive and the 97/43/Euratom Directive (on health protection of individuals against the dangers of ionising radiation in relation to medical exposure). Concerning the Title 7. of the new European BSS Directive, which refers to the Radiation Protection at work places with increased levels of natural radiation exposure, the Radiation Protection Regulations provides that the authority responsible for recording, monitoring and introducing protection measures at these places is the GAEC. Practices where effective doses to the workers due to increased natural radiation levels, may exceed 1mSv/y, have to be specified and authorised by the GAEC. The identification procedure is ongoing

  11. Effects of the ionizing radiation in natural food colours

    International Nuclear Information System (INIS)

    Cosentino, Helio Morrone

    2005-01-01

    The world's fast growing population and its consequent increase in demand for food has driven mankind into improving technologies which ensure a safer supply of such commodities. Both food radiation processing and its constituents are highlighted as a feasible alternative technique capable of meeting food safety standards. Natural dyes are extensively employed in the food industry thanks to their colour enhancing properties on food products. This paper has aimed at studying the effects of ionizing radiation on three natural dyes: carminic acid and its derivatives (cochineal dyes), bixine and its salts (annatto dyes) and curcumin (turmeric dyes), used in the food and cosmetic industries within dilutions and doses those goods might eventually be processed in. It also envisages clarifying the compatibility of the irradiation technique with the keeping of such relevant sensorial attribute which is the product colour. Spectrophotometry and capillary electrophoresis were the analytic methods employed. All in all, a colour decrease proportional to the increase on the applied gamma radiation (1 to 32 kGy) has been observed. The annatto dyes have proven moderately stable whereas turmeric has shown to be highly sensitive to radiation. Those results shall be taken into account as far as the need to alter the formulae additive amount in the product is concerned whenever undergoing radiation processing. (author)

  12. Radiation processing of natural polymers using low energy electron beam

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    2004-01-01

    Radiation processing is widely used in Japan and the economic scale of radiation application amounted to about 71 b$ (ratio relative to GDP: 1.7%) in total. It consisted of 60 b$ (85%) in industry, 10 b$ (14%) in medicine and 1 b$ (1%) in agriculture. Irradiation using gamma-ray from 60 Co and electron beam is commercially used for the sterilization and modification of materials. Utilization of natural polymers by radiation has been investigated for recycling the natural resources and reducing the environmental pollution. Polysaccharides such as chitosan, sodium alginate, carrageenan, cellulose, pectin were easily degraded by irradiation and induced various kinds of biological activities, i.e. anti-bacterial activity, elicitor activity, plant growth promotion, suppression of environmental stress on plants. Radiation degraded chitosan was effective to enhance the growth of plants in tissue culture. Low energy electron beam (EB) irradiation has a variety of applications and good safety. A self-shielded low energy electron accelerator system needs an initial investment much lower than a 60 Co facility. It was demonstrated that the liquid sample irradiation system using low energy EB was effective not only for the preparation of degraded polysaccharides but also for radiation vulcanization of natural rubber latex (RVNRL). Some carbohydrate derivatives, carboxymethylcellulose (CMC), carboxymethyl-starch and carboxymethyl-chitin/chitosan, can be crosslinked under certain radiation condition and produced the biodegradable hydrogel for medical and agricultural use. Treatment of soybean seeds by low energy EB enhanced the growth and the number of rhizobia on the root. (author)

  13. Preparation of highly stabilised natural rubber latex for radiation vulcanisation

    International Nuclear Information System (INIS)

    Kulatunge, S.S.; Nadarajah, M.; Kalyani, N.M.V.; Chandralal, H.N.K.K.; Devendra, R.

    1996-01-01

    There is a bright future for radiation vulcanised natural rubber latex (RVNRL) but there are problems in manufacturing it as the centrifuged latex to be used for radiation has to be kept for at least a month or sometimes even three to six months before adding the sensitisers and even then the latex sometimes coagulates on adding the sensitisers. This paper describes a process by which the latex can be stabilised by addition of an anionic soap before centrifuging so that it has a high mechanical stability and hence can be used even within one week of the manufacture of the centrifuged latex

  14. Radiation vulcanization of natural rubber latex with low energy accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Haque, Emdadul; Makuuchi, Keizo; Ikeda, Kenichi; Yoshii, Fumio; Kume Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Mitomo, Hiroshi [Gunma Univ., Faculty of Engineering, Department of Biological and Chemical Engineering, Kiryu, Gunma (Japan)

    2001-03-01

    The radiation vulcanization of natural rubber latex (RVNRL) with the recently installed electron beam (EB) pilot plant at Takasaki Radiation Chemistry Research Establishment, Takasaki, Japan has been discussed. The accelerating voltage and beam current of the plant are 250 kV and 10 mA respectively. The plant has a reaction vessel with the capacity of 18 liters latex to irradiate at a time. In order to obtain a suitable setting of experimental for RVNRL under EB of the plant the parameters such as irradiation time, defoamer concentration, volume of latex, beam current etc. are being optimized by varying the individual parameter at a constant set of the other variables. (author)

  15. Fifth International Symposium on the Natural Radiation Environment

    International Nuclear Information System (INIS)

    Porstendoerfer, J.; Swedjemark, G.A.; Baeverstam, U.; Lowder, W.M.; Miller, K.M.; Fisenne, I.M.

    1993-01-01

    The fifth International Symposium on the Natural Radiation Environment organized a series of tutorial sessions. One of the five major fields concerned with the radon issue. The tutorials dealt with important issues of the radon problem and covered the following aspects: Cosmic and Terrestrial Gamma Radiation Measurement, Properties and Behaviour of Radon and Thoron and Their Decay Products in the Air, Radon and Radon Daughters Metrology: Basic Aspects Long Lived Radionuclides in the Environment, in Food and in Human Beings, Design and Analysis of Radon Surveys with Epidemiological Utility

  16. A space weather index for the radiation field at aviation altitudes

    Directory of Open Access Journals (Sweden)

    Meier Matthias M.

    2014-04-01

    Full Text Available The additional dose contribution to the radiation exposure at aviation altitudes during Solar Particle Events (SPEs has been a matter of concern for many years. After the Halloween storms in 2003 several airlines began to implement mitigation measures such as rerouting and lowering flight altitudes in response to alerts on the NOAA S-scale regarding solar radiation storms. These alerts are based on the integral proton flux above 10 MeV measured aboard the corresponding GOES-satellite which is operated outside the Earth’s atmosphere in a geosynchronous orbit. This integral proton flux has, however, been proved to be an insufficient parameter to apply to the radiation field at aviation altitudes without an accompanying analysis of the shape of the energy spectrum. Consequently, false alarms and corresponding disproportionate reactions ensued. Since mitigating measures can be quite cost-intensive, there has been a demand for appropriate space weather information among responsible airline managers for about a decade. Against this background, we propose the introduction of a new Space Weather index D, based on dose rates at aviation altitudes produced by solar protons during solar radiation storms, as the relevant parameter for the assessment of corresponding radiation exposure. The Space Weather index D is a natural number given by a graduated table of ranges of dose rates in ascending order which is derived by an equation depending on the dose rate of solar protons.

  17. Radiation Synthesis of Superabsorbent Polymers Based on Natural Polymers

    International Nuclear Information System (INIS)

    Sen, Murat; Hayrabolulu, Hande

    2010-01-01

    The objectives of proposed research contract were first synthesize superabsorbent polymers based on natural polymers to be used as disposable diapers and soil conditioning materials in agriculture, horticulture and other super adsorbent using industries. We have planned to use the natural polymers; locust beam gum, tara gum, guar gum and sodium alginate on the preparation of natural superabsorbent polymers(SAP). The aqueous solution of natural polymers and their blends with trace amount of monomer and cross-linking agents will be irradiated in paste like conditions by gamma rays for the preparation of cross-linked superabsorbent systems. The water absorption and deswellling capacity of prepared super adsorbents and retention capacity, absorbency under load, suction power, swelling pressure and pet-rewet properties will be determined. Use of these materials instead of synthetic super absorbents will be examined by comparing the performance of finished products. The experimental studies achieved in the second year of project mainly on the effect of radiation on the chemistry of sodium alginate polymers in different irradiation conditions and structure-property relationship particularly with respect to radiation induced changes on the molecular weight of natural polymers and preliminary studies on the synthesis of natural-synthetic hydride super adsorbent polymers were given in details

  18. Supersymmetry with Radiatively-Driven Naturalness: Implications for WIMP and Axion Searches

    Directory of Open Access Journals (Sweden)

    Kyu Jung Bae

    2015-05-01

    Full Text Available By insisting on naturalness in both the electroweak and quantum chromodynamics (QCD sectors of the minimal supersymmetric standard model (MSSM, the portrait for dark matter production is seriously modified from the usual weakly interacting massive particle (WIMP miracle picture. In supersymmetry (SUSY models with radiatively-driven naturalness (radiative natural SUSY or radiative natural SUSY (RNS which include a Dine–Fischler–Srednicki–Zhitnitsky (DFSZ-like solution to the strong charge-conjugation-parity (CP and SUSY \\(\\mu\\ problems, dark matter is expected to be an admixture of both axions and higgsino-like WIMPs. The WIMP/axion abundance calculation requires simultaneous solution of a set of coupled Boltzmann equations which describe quasi-stable axinos and saxions. In most of parameter space, axions make up the dominant contribution of dark matter although regions of WIMP dominance also occur. We show the allowed range of Peccei-Quinn (PQ scale \\(f_a\\ and compare to the values expected to be probed by the axion dark matter search experiment (ADMX axion detector in the near future. We also show WIMP detection rates, which are suppressed from usual expectations, because now WIMPs comprise only a fraction of the total dark matter. Nonetheless, ton-scale noble liquid detectors should be able to probe the entirety of RNS parameter space. Indirect WIMP detection rates are less propitious since they are reduced by the square of the depleted WIMP abundance.

  19. Radiation reaction in curved space-time:. local method

    Science.gov (United States)

    Gal'Tsov, Dmitri; Spirin, Pavel; Staub, Simona

    Although consensus seems to exist about the validity of equations accounting for radiation reaction in curved space-time, their previous derivations were criticized recently as not fully satisfactory: some ambiguities were noticed in the procedure of integration of the field momentum over the tube surrounding the world-line. To avoid these problems we suggest a purely local derivation dealing with the field quantities defined only on the world-line. We consider point particle interacting with scalar, vector (electromagnetic) and linearized gravitational fields in the (generally non-vacuum) curved space-time. To properly renormalize the self-action in the gravitational case, we use a manifestly reparameterization-invariant formulation of the theory. Scalar and vector divergences are shown to cancel for a certain ratio of the corresponding charges. We also report on a modest progress in extending the results for the gravitational radiation reaction to the case of non-vacuum background.

  20. Anatomical models for space radiation applications: an overview.

    Science.gov (United States)

    Atwell, W

    1994-10-01

    Extremely detailed computerized anatomical male (CAM) and female (CAF) models that have been developed for use in space radiation analyses are discussed and reviewed. Recognizing that the level of detail may currently be inadequate for certain radiological applications, one of the purposes of this paper is to elicit specific model improvements or requirements from the scientific user-community. Methods and rationale are presented which describe the approach used in the Space Shuttle program to extrapolate dosimetry measurements (skin doses) to realistic astronaut body organ doses. Several mission scenarios are presented which demonstrate the utility of the anatomical models for obtaining specific body organ exposure estimates and can be used for establishing cancer morbidity and mortality risk assessments. These exposure estimates are based on the trapped Van Allen belt and galactic cosmic radiation environment models and data from the major historical solar particle events.

  1. SOA based intensive support system for space radiation data

    International Nuclear Information System (INIS)

    Goranova, M.; Shishedjiev, B.; Genova, S.; Semkova, J.

    2013-01-01

    Modern data intensive science involves heterogeneous and structured data sets in sophisticated data formats. Scientists need access to distributed computing and data sources and support for remote access to expensive, multinational specialized instruments. Scientists need effective software for data analysis, querying, accessing and visualization. The interaction between computer science and science and engineering becomes essential for the automation of data manipulation. The key solution uses the Service-oriented Architecture (SOA) in the field of science and Grid computing. The goal of this paper is managing the scientific data received by the Lyulin-5 particle telescope used in MATROSHKA-R experiment performed at the International Space Station (ISS). The dynamics of radiation characteristics and their dependency on the time and the orbital parameters have been established. The experiment helps the accurate estimation of the impact of space radiation on human health in long-duration manned missions

  2. Nature as Children's Space: A Systematic Review

    Science.gov (United States)

    Adams, Sabirah; Savahl, Shazly

    2017-01-01

    The emerging interest in "spaces of childhood" over the past two decades can be identified across numerous disciplines. A substantial body of research has indicated that children's active engagement within the natural environment is associated with a range of cognitive, physical, affective, and moral developmental benefits. Although…

  3. Radiation protection with respect for nature, views from Japan

    International Nuclear Information System (INIS)

    Fujimoto, K.

    2002-01-01

    My new proposal was summarised below for the protection of environment based on the understanding that we can exist on earth only in the balance of nature. We must follow the providence of nature and attain the golden mean in nature. For justification and optimisation, any concrete idea has not been provided, but one of the approaches was shown in the present paper. We have to abandon anthropocentrism and change our sense of value and moral standards with the respect for nature. For practice, the dose limit at the boundary of facilities could be derived from the regional difference of dose rates in the world as an acceptable level to nature. The dose rate would be around 1 mGy per year. Release limit for radionuclides could be defined separately to natural and artificial nuclides. For natural radionuclides, normal ambient concentration can be used for the limit. For artificial radionuclides, the limit might be based on the derived dose rate taking into account the accumulation. For intervention, an analogical approach to natural disasters could be applied. When the situation is easy to recover, then it should be restored. In case it is not easy, then the damage should be confined not to spread outside. For potential exposure, two approaches are suggested for prevention and mitigation. Renewal system is proposed for prevention and decentralization for mitigation. A rigid number for the dose limit is shown in the present paper, as well as renewal or relocation for the radiation protection for environment. However, it is not necessary to take them as they are. For the practical application, definitely it requires some modification. Therefore, present suggestions should be taken as some hint for the establishment of radiation protection system for environment. Especially the suggested dose limit of 1 mGy per year should be taken as the lowest limit for the acceptable level to nature. (author)

  4. Space Radiation Analysis for the Mark III Spacesuit

    Science.gov (United States)

    Atwell, Bill; Boeder, Paul; Ross, Amy

    2013-01-01

    NASA has continued the development of space systems by applying and integrating improved technologies that include safety issues, lightweight materials, and electronics. One such area is extravehicular (EVA) spacesuit development with the most recent Mark III spacesuit. In this paper the Mark III spacesuit is discussed in detail that includes the various components that comprise the spacesuit, materials and their chemical composition that make up the spacesuit, and a discussion of the 3-D CAD model of the Mark III spacesuit. In addition, the male (CAM) and female (CAF) computerized anatomical models are also discussed in detail. We combined the spacesuit and the human models, that is, we developed a method of incorporating the human models in the Mark III spacesuit and performed a ray-tracing technique to determine the space radiation shielding distributions for all of the critical body organs. These body organ shielding distributions include the BFO (Blood-Forming Organs), skin, eye, lungs, stomach, and colon, to name a few, for both the male and female. Using models of the trapped (Van Allen) proton and electron environments, radiation exposures were computed for a typical low earth orbit (LEO) EVA mission scenario including the geostationary (GEO) high electron environment. A radiation exposure assessment of these mission scenarios is made to determine whether or not the crew radiation exposure limits are satisfied, and if not, the additional shielding material that would be required to satisfy the crew limits.

  5. Comparison of space flight and heavy ion radiation induced genomic/epigenomic mutations in rice (Oryza sativa)

    Science.gov (United States)

    Shi, Jinming; Lu, Weihong; Sun, Yeqing

    2014-04-01

    Rice seeds, after space flight and low dose heavy ion radiation treatment were cultured on ground. Leaves of the mature plants were obtained for examination of genomic/epigenomic mutations by using amplified fragment length polymorphism (AFLP) and methylation sensitive amplification polymorphism (MSAP) method, respectively. The mutation sites were identified by fragment recovery and sequencing. The heritability of the mutations was detected in the next generation. Results showed that both space flight and low dose heavy ion radiation can induce significant alterations on rice genome and epigenome (P < 0.05). For both genetic and epigenetic assays, while there was no significant difference in mutation rates and their ability to be inherited to the next generation, the site of mutations differed between the space flight and radiation treated groups. More than 50% of the mutation sites were shared by two radiation treated groups, radiated with different LET value and dose, while only about 20% of the mutation sites were shared by space flight group and radiation treated group. Moreover, in space flight group, we found that DNA methylation changes were more prone to occur on CNG sequence than CG sequence. Sequencing results proved that both space flight and heavy ion radiation induced mutations were widely spread on rice genome including coding region and repeated region. Our study described and compared the characters of space flight and low dose heavy ion radiation induced genomic/epigenomic mutations. Our data revealed the mechanisms of application of space environment for mutagenesis and crop breeding. Furthermore, this work implicated that the nature of mutations induced under space flight conditions may involve factors beyond ion radiation.

  6. Space Station Validation of Advanced Radiation-Shielding Polymeric Materials, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In Subtopic X11.01, NASA has identified the need to develop advanced radiation-shielding materials and systems to protect humans from the hazards of space radiation...

  7. Space Station Validation of Advanced Radiation-Shielding Polymeric Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In Subtopic X11.01, NASA has identified the need to develop advanced radiation-shielding materials and systems to protect humans from the hazards of space radiation...

  8. Space Station Validation of Advanced Radiation-Shielding Polymeric Materials, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — In Subtopic X11-01, NASA has identified the need to develop advanced radiation-shielding materials and systems to protect humans from the hazards of space radiation...

  9. NASA Strategy to Safely Live and Work in the Space Radiation Environment

    Science.gov (United States)

    Cucinotta, Francis; Wu, Honglu; Corbin, Barbara; Sulzman, Frank; Kreneck, Sam

    2007-01-01

    This viewgraph document reviews the radiation environment that is a significant potential hazard to NASA's goals for space exploration, of living and working in space. NASA has initiated a Peer reviewed research program that is charged with arriving at an understanding of the space radiation problem. To this end NASA Space Radiation Laboratory (NSRL) was constructed to simulate the harsh cosmic and solar radiation found in space. Another piece of the work was to develop a risk modeling tool that integrates the results from research efforts into models of human risk to reduce uncertainties in predicting risk of carcinogenesis, central nervous system damage, degenerative tissue disease, and acute radiation effects acute radiation effects.

  10. Mitigating radiation damage of single photon detectors for space applications

    Energy Technology Data Exchange (ETDEWEB)

    Anisimova, Elena; Higgins, Brendon L.; Bourgoin, Jean-Philippe [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); Cranmer, Miles [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); Choi, Eric [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); Magellan Aerospace, Ottawa, ON (Canada); Hudson, Danya; Piche, Louis P.; Scott, Alan [Honeywell Aerospace (formerly COM DEV Ltd.), Ottawa, ON (Canada); Makarov, Vadim [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); University of Waterloo, Department of Electrical and Computer Engineering, Waterloo, ON (Canada); Jennewein, Thomas [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); Canadian Institute for Advanced Research, Quantum Information Science Program, Toronto, ON (Canada)

    2017-12-15

    Single-photon detectors in space must retain useful performance characteristics despite being bombarded with sub-atomic particles. Mitigating the effects of this space radiation is vital to enabling new space applications which require high-fidelity single-photon detection. To this end, we conducted proton radiation tests of various models of avalanche photodiodes (APDs) and one model of photomultiplier tube potentially suitable for satellite-based quantum communications. The samples were irradiated with 106 MeV protons at doses approximately equivalent to lifetimes of 0.6, 6, 12 and 24 months in a low-Earth polar orbit. Although most detection properties were preserved, including efficiency, timing jitter and afterpulsing probability, all APD samples demonstrated significant increases in dark count rate (DCR) due to radiation-induced damage, many orders of magnitude higher than the 200 counts per second (cps) required for ground-to-satellite quantum communications. We then successfully demonstrated the mitigation of this DCR degradation through the use of deep cooling, to as low as -86 C. This achieved DCR below the required 200 cps over the 24 months orbit duration. DCR was further reduced by thermal annealing at temperatures of +50 to +100 C. (orig.)

  11. Contribution from natural and man-made background radiations to Indian population

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Eappen, K.P.; Shaikh, A.N.; Mayya, Y.S.; Puranik, V.D.

    2005-01-01

    Living organisms are exposed to ionizing radiation existed naturally. Sources of ionizing radiation are cosmic ray, which comes from outer space, terrestrial radionuclides which occurs in the earth's crust, in building materials and in air, water and food and in human body itself. The annual effective dose at sea level from cosmic rays is 240 μSv. It can also vary as a result of human activities and practices. Component of the sources of exposures to Indian population has been assessed based on the data generated. Total contribution to the natural sources to the Indian population works out to be 2.3 mSv/y as against the global value of 2.4 mSv/y. Estimated contribution to the background radiation from actual practices such as mining of heavy metals (U and Th), coal fired power plants, mining of phosphate rocks and its use as fertilizers, production of natural gas, production of gas mantles and luminescent dial and air travel works out be 1.24 x 10 -3 mSv/y. Nuclear weapon tests contributes about 0.008 mSv/y and the exposure due to nuclear power production contributes about 5.0 x 10 -5 mSv/y to the background radiation. Brief review and comparison of the dose rates arising from natural and man-made sources to the Indian population is given. (author)

  12. Comparison of Space Radiation Calculations from Deterministic and Monte Carlo Transport Codes

    Science.gov (United States)

    Adams, J. H.; Lin, Z. W.; Nasser, A. F.; Randeniya, S.; Tripathi, r. K.; Watts, J. W.; Yepes, P.

    2010-01-01

    The presentation outline includes motivation, radiation transport codes being considered, space radiation cases being considered, results for slab geometry, results from spherical geometry, and summary. ///////// main physics in radiation transport codes hzetrn uprop fluka geant4, slab geometry, spe, gcr,

  13. Evaluation of natural radiation exposure of the French population

    International Nuclear Information System (INIS)

    Billon, S.; Morin, A.; Baysson, H.; Gambard, J.P.; Rannou, A.; Tirmarche, M.; Laurier, D.; Caer, S.

    2004-01-01

    Exposure of the French population to ionising radiation is mainly due to natural radiation (i.e. exposure through: inhalation of radon decay products, external radiation of terrestrial and cosmic origin and water and food ingestion). In an epidemiological context, it is necessary to estimate as precisely as possible the population exposure, in order to study its influence on health indicators. In this aim, indicators of population exposure should be created taking into account results of environmental measurements by controlling the different factors that may influence these measurements (dwelling characteristics, seasonal variations, population density). The distribution of these exposures should also be studied at different geographical levels (department, job area). This work updates the estimation of the French population exposure to natural radiation. Radon exposure indicators have been based on concentrations measured in dwellings, corrected on season and dwelling characteristics (departmental range: 19-297 Bq/m 3 ). Indicators of terrestrial gamma ray exposure have been based on measured indoor and outdoor dose rates adjusted on dwelling characteristics (22-95 nSv/h). Cosmic ray exposure has been evaluated from altitude and weighted by population density (0.27-0.38 mSv/yr). Due to these three components, the effective annual dose was estimated to be at 2.2 mSv. (author)

  14. Status of the European Atlas of Natural Radiation

    International Nuclear Information System (INIS)

    Bossew, P.; Tollefsen, T.; Cinelli, G.; De Cort, M.; Gruber, V.

    2015-01-01

    According to the EURATOM (European Atomic Energy Community) Treaty, one of the missions of the Joint Research Centre (JRC) of the European Commission (EC) is to collect, process, evaluate and present data on environmental radioactivity. In 2006, the JRC started the 'European Atlas of Natural Radiation' project, in order to give an overview of the geographic distribution of sources of, and exposures to, natural radiation. As a first task, a map of indoor radon concentration was created, because in most cases this is the most important contribution to exposure, and since it could be expected that data collection would take quite some time, because radon (Rn) surveys are very differently advanced between European countries. The authors show the latest status of this map. A technically more ambitious map proved the one of the geo-genic Rn potential (RP), due to heterogeneity of data sources across Europe and the need to develop models to estimate a harmonised quantity which adequately measures or classifies the RP. Further maps currently in the making include those of secondary cosmic radiation, of terrestrial gamma radiation and of the concentrations of the elements U, Th and K that are its source. In this article, the authors show the progress of some of these maps. (authors)

  15. Radiation Processing of Natural Polymers for Industrial Applications

    International Nuclear Information System (INIS)

    Hegazy, E.A.

    2008-01-01

    Radiation induced degradation technology is a new and promising application of ionizing radiation to develop viscose, pulp, paper, food preservation, pharmaceutical production, and natural bioactive agents industries. Controlling the degree of degradation, uniform molecular weight distribution, saving achieved in the chemicals (used in conventional methods) on a cost basis, and environmentally friendly process are the beneficial effects of using radiation technology in these industries. However, for some development countries such technology is not economic. Therefore, a great effort should be done to reduce the cost required for such technologies. One of the principle factors for reducing the cost is achieving the degradation at low irradiation doses. The addition of some additives such as potassium per-sulfate (KPS), ammonium per-sulfate (APS), or H 2 O 2 to natural polymers (carboxy-methylcellulose (CMC), chitosan, carrageenan and Na-alginate) during irradiation process accelerates their degradation. The highest degradation rate of polysaccharides obtained when APS was used. The end product of irradiated CMC, chitosan, carrageenan and Na-alginate may be used as food additive or benefited in agricultural purposes. On the other hand, radiation crosslinking of PAAm or PNIPAAm is affected by the presence of natural polymer like CMC-Na and carrageenan due to their degradability which could be controlled according to its concentration in the bulk medium and irradiation dose. Accordingly, the gel content, thermo-sensitivity (LCST) and swelling properties of PNIPAAm based natural polymers could be controlled. The swelling of the prepared copolymer hydrogels was investigated for its possible use in personal care articles particularly diapers or as carriers for drug delivery systems. The prepared crosslinked copolymers possessed high and fast swelling properties in simulated urine media and the swelling ratios of CMC-Na /PAAm gels in urine are acceptable for diaper

  16. Radiation vulcanized natural rubber latex is not cytotoxic

    International Nuclear Information System (INIS)

    Nakamura, Akitada; Ikarashi, Y.; Tsuchiya, T.; Kaniwa, M.

    1990-01-01

    It has been reported that urethritis and/or urethral strictures caused by urinary catheters relates to cytotoxicities of their materials, and that natural rubber latex (NRL) materials often show the strong cytotoxicities. This paper reports the cytotoxicity testing method using chinese hamster V79 cultured cells, clarifies that the toxicities of NRLs vulcanized by the conventional processes are due mainly to the contents of zinc dialkyldithiocarbamates in the materials, and that the cytotoxicity of radiation vulcanized NRL (RVNRL) is very weak. (author)

  17. How Space Radiation Risk from Galactic Cosmic Rays at the International Space Station Relates to Nuclear Cross Sections

    Science.gov (United States)

    Lin, Zi-Wei; Adams, J. H., Jr.

    2005-01-01

    Space radiation risk to astronauts is a major obstacle for long term human space explorations. Space radiation transport codes have thus been developed to evaluate radiation effects at the International Space Station (ISS) and in missions to the Moon or Mars. We study how nuclear fragmentation processes in such radiation transport affect predictions on the radiation risk from galactic cosmic rays. Taking into account effects of the geomagnetic field on the cosmic ray spectra, we investigate the effects of fragmentation cross sections at different energies on the radiation risk (represented by dose-equivalent) from galactic cosmic rays behind typical spacecraft materials. These results tell us how the radiation risk at the ISS is related to nuclear cross sections at different energies, and consequently how to most efficiently reduce the physical uncertainty in our predictions on the radiation risk at the ISS.

  18. Development of measuring technique of accumulated natural radiation

    Energy Technology Data Exchange (ETDEWEB)

    Imai, Masahiko; Kitahara, Akiharu; Inokoshi, Yukio; Tanizaki, Yoshiyuki [Tokyo Metropolitan Isotope Research Center (Japan); Kamijo, Tomohiro

    1993-02-01

    Three volcanic ash layers in Tama Hill were used to measure accumulated natural radiation and to estimate eruption ages. TLD elements were buried in the volcanic ash layers for a certain period and TL measurements were performed. Then the annual doses of {gamma}-rays and cosmic rays in the layers were determined. The concentrations of K, {sup 232}U and {sup 238}Th in the volcanic ashes were determined by activation analysis. On the basis of the data, the annual doses of {beta}-rays were calculated. As a total annual dose of natural radiation, the sum of the annual doses of {gamma}-ray, cosmic ray and {beta}-ray was calculated. Quartz grains were picked up from the volcanic ash samples and divided to some parts. Each part of the grains was irradiated with {sup 60}Co {gamma}-rays. Artificial irradiations were performed to more than five different doses. Then, ESR spectrum and TL of each part of grains were measured. The signal intensity increased linearly with dose. The accumulated doses of natural radiation were obtained by extrapolating the least-square-fitting line. The age was estimated by dividing accumulated dose with total annual dose. There was no significant difference in the results between ESR method and TL method. The obtained ages were near the values estimated by fission track method. We must improve measuring methods of ESR and TL, and purification method of sample in order to estimate the ages more accurately. (author).

  19. Validity of the Aluminum Equivalent Approximation in Space Radiation Shielding

    Science.gov (United States)

    Badavi, Francis F.; Adams, Daniel O.; Wilson, John W.

    2009-01-01

    The origin of the aluminum equivalent shield approximation in space radiation analysis can be traced back to its roots in the early years of the NASA space programs (Mercury, Gemini and Apollo) wherein the primary radiobiological concern was the intense sources of ionizing radiation causing short term effects which was thought to jeopardize the safety of the crew and hence the mission. Herein, it is shown that the aluminum equivalent shield approximation, although reasonably well suited for that time period and to the application for which it was developed, is of questionable usefulness to the radiobiological concerns of routine space operations of the 21 st century which will include long stays onboard the International Space Station (ISS) and perhaps the moon. This is especially true for a risk based protection system, as appears imminent for deep space exploration where the long-term effects of Galactic Cosmic Ray (GCR) exposure is of primary concern. The present analysis demonstrates that sufficiently large errors in the interior particle environment of a spacecraft result from the use of the aluminum equivalent approximation, and such approximations should be avoided in future astronaut risk estimates. In this study, the aluminum equivalent approximation is evaluated as a means for estimating the particle environment within a spacecraft structure induced by the GCR radiation field. For comparison, the two extremes of the GCR environment, the 1977 solar minimum and the 2001 solar maximum, are considered. These environments are coupled to the Langley Research Center (LaRC) deterministic ionized particle transport code High charge (Z) and Energy TRaNsport (HZETRN), which propagates the GCR spectra for elements with charges (Z) in the range I aluminum equivalent approximation for a good polymeric shield material such as genetic polyethylene (PE). The shield thickness is represented by a 25 g/cm spherical shell. Although one could imagine the progression to greater

  20. Cytogenetic examination of cosmonauts for space radiation exposure estimation

    Science.gov (United States)

    Snigiryova, G. P.; Novitskaya, N. N.; Fedorenko, B. S.

    2012-08-01

    PurposeTo evaluate radiation induced chromosome aberration frequency in peripheral blood lymphocytes of cosmonauts who participated in flights on Mir Orbital Station and ISS (International Space Station). Materials and methodsCytogenetic examination which has been performed in the period 1992-2008 included the analysis of chromosome aberrations using conventional Giemsa staining method in 202 blood samples from 48 cosmonauts who participated in flights on Mir Orbital Station and ISS. ResultsSpace flights led to an increase of chromosome aberration frequency. Frequency of dicentrics plus centric rings (Dic+Rc) depend on the space flight duration and accumulated dose value. After the change of space stations (from Mir Orbital Station to ISS) the radiation load of cosmonauts based on data of cytogenetic examination decreased. Extravehicular activity also adds to chromosome aberration frequency in cosmonauts' blood lymphocytes. Average doses after the first flight, estimated by the frequency of Dic+Rc, were 227 and 113 mGy Eq for long-term flights (LTF) and 107 and 53 mGy Eq for short-term flights (STF). ConclusionCytogenetic examination of cosmonauts can be applied to assess equivalent doses.

  1. Mechanical stratigraphic controls on natural fracture spacing and penetration

    Science.gov (United States)

    McGinnis, Ronald N.; Ferrill, David A.; Morris, Alan P.; Smart, Kevin J.; Lehrmann, Daniel

    2017-02-01

    Fine-grained low permeability sedimentary rocks, such as shale and mudrock, have drawn attention as unconventional hydrocarbon reservoirs. Fracturing - both natural and induced - is extremely important for increasing permeability in otherwise low-permeability rock. We analyze natural extension fracture networks within a complete measured outcrop section of the Ernst Member of the Boquillas Formation in Big Bend National Park, west Texas. Results of bed-center, dip-parallel scanline surveys demonstrate nearly identical fracture strikes and slight variation in dip between mudrock, chalk, and limestone beds. Fracture spacing tends to increase proportional to bed thickness in limestone and chalk beds; however, dramatic differences in fracture spacing are observed in mudrock. A direct relationship is observed between fracture spacing/thickness ratio and rock competence. Vertical fracture penetrations measured from the middle of chalk and limestone beds generally extend to and often beyond bed boundaries into the vertically adjacent mudrock beds. In contrast, fractures in the mudrock beds rarely penetrate beyond the bed boundaries into the adjacent carbonate beds. Consequently, natural bed-perpendicular fracture connectivity through the mechanically layered sequence generally is poor. Fracture connectivity strongly influences permeability architecture, and fracture prediction should consider thin bed-scale control on fracture heights and the strong lithologic control on fracture spacing.

  2. BioSentinel: Biosensors for Deep-Space Radiation Study

    Science.gov (United States)

    Lokugamage, Melissa P.; Santa Maria, Sergio R.; Marina, Diana B.; Bhattacharya, Sharmila

    2016-01-01

    The BioSentinel mission will be deployed on NASA's Exploration Mission 1 (EM-1) in 2018. We will use the budding yeast, Saccharomyces cerevisiae, as a biosensor to study the effect of deep-space radiation on living cells. The BioSentinel mission will be the first investigation of a biological response to space radiation outside Low Earth Orbit (LEO) in over 40 years. Radiation can cause damage such as double stand breaks (DSBs) on DNA. The yeast cell was chosen for this mission because it is genetically controllable, shares homology with human cells in its DNA repair pathways, and can be stored in a desiccated state for long durations. Three yeast strains will be stored dry in multiple microfluidic cards: a wild type control strain, a mutant defective strain that cannot repair DSBs, and a biosensor strain that can only grow if it gets DSB-and-repair events occurring near a specific gene. Growth and metabolic activity of each strain will be measured by a 3-color LED optical detection system. Parallel experiments will be done on the International Space Station and on Earth so that we can compare the results to that of deep space. One of our main objectives is to characterize the microfluidic card activation sequence before the mission. To increase the sensitivity of yeast cells as biosensors, desiccated yeast in each card will be resuspended in a rehydration buffer. After several weeks, the rehydration buffer will be exchanged with a growth medium in order to measure yeast growth and metabolic activity. We are currently working on a time-course experiment to better understand the effects of the rehydration buffer on the response to ionizing radiation. We will resuspend the dried yeast in our rehydration medium over a period of time; then each week, we will measure the viability and ionizing radiation sensitivity of different yeast strains taken from this rehydration buffer. The data obtained in this study will be useful in finalizing the card activation sequence for

  3. Monitoring Space Radiation Hazards with the Responsive Environmental Assessment Commercially Hosted (REACH) Project

    Science.gov (United States)

    Mazur, J. E.; Guild, T. B.; Crain, W.; Crain, S.; Holker, D.; Quintana, S.; O'Brien, T. P., III; Kelly, M. A.; Barnes, R. J.; Sotirelis, T.

    2017-12-01

    The Responsive Environmental Assessment Commercial Hosting (REACH) project uses radiation dosimeters on a commercial satellite constellation in low Earth orbit to provide unprecedented spatial and time sampling of space weather radiation hazards. The spatial and time scales of natural space radiation environments coupled with constraints for the hosting accommodation drove the instrumentation requirements and the plan for the final orbital constellation. The project has delivered a total of thirty two radiation dosimeter instruments for launch with each instrument containing two dosimeters with different passive shielding and electronic thresholds to address proton-induced single-event effects, vehicle charging, and total ionizing dose. There are two REACH instruments currently operating with four more planned for launch by the time of the 2017 meeting. Our aim is to field a long-lived system of highly-capable radiation detectors to monitor the hazards of single-event effects, total ionizing dose, and spacecraft charging with maximized spatial coverage and with minimal time latency. We combined a robust detection technology with a commercial satellite hosting to produce a new demonstration for satellite situational awareness and for other engineering and science applications.

  4. Space and motion in nature and Scripture: Galileo, Descartes, Newton.

    Science.gov (United States)

    Janiak, Andrew

    2015-06-01

    In the Scholium to the Definitions in Principia mathematica, Newton departs from his main task of discussing space, time and motion by suddenly mentioning the proper method for interpreting Scripture. This is surprising, and it has long been ignored by scholars. In this paper, I argue that the Scripture passage in the Scholium is actually far from incidental: it reflects Newton's substantive concern, one evident in correspondence and manuscripts from the 1680s, that any general understanding of space, time and motion must enable readers to recognize the veracity of Biblical claims about natural phenomena, including the motion of the earth. This substantive concern sheds new light on an aspect of Newton's project in the Scholium. It also underscores Newton's originality in dealing with the famous problem of reconciling theological and philosophical conceptions of nature in the seventeenth century. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Research on Paramecium aurelia sensitivity factors to natural ionizing radiations

    International Nuclear Information System (INIS)

    Croute, F.; Soleilhavoup, J.P.; Gros, N.; Planel, H.

    1976-01-01

    Previous results have demonstrated that the proliferative activity of Paramecium aurelia is linked to the level of natural ionizing radiations since this activity is decreased under radiation protection (lead cell) and increased under chronic exposure to very low dose of 60 Co gamma rays. The results of this investigation indicate that cell sensitivity in spite of variations in natural irradiation levels can be isolated; they are called 'radioresistant' in opposition to 'radiosensitive' cells which present the other response. These characters are being retained for 9 months after the strains have been isolated. On the other hand, in the case of radiosensitive strains, it has been demonstrated that autogamy affected the cell response to background irradiation; no response at all occured on the very day when autogamy took place, but it reached a maximum level 8 days approximately after autogamy. Moreover, it has been proved that the catalase activity of Paramecium aurelia is higher than those already studied in other cell varieties. This great amount of catalase, which seems to vary with the age of cultures after autogamy, could act on Paramecium sensitivity to very low radiation doses [fr

  6. High level natural radiation areas with special regard to Ramsar

    International Nuclear Information System (INIS)

    Sohrabi, M.

    1993-01-01

    The studies of high level natural radiation areas (HLNRAs) around the world are of great importance for determination of risks due to long-term low-level whole body exposures of public. Many areas of the world possess HLNRAs the number of which depends on the criteria defined. Detailed radiological studies have been carried out in some HLNRAs the results of which have been reported at least in three international conferences. Among the HLNRAs, Ramsar has so far the highest level of natural radiation in some areas where radiological studies have been of concern. A program was established for Ramsar and its HLNRAs to study indoor and outdoor gamma exposures and external and internal doses of the inhabitants, 226 Ra content of public water supplies and hot springs, of food stuffs, etc., 222 Rn levels measured in 473 rooms of near 350 houses, 16 schools and 89 rooms and many locations of old and new Ramsar Hotels in different seasons, cytogenetic effects on inhabitants of Talesh Mahalleh, the highest radiation area, compared to that of a control area and radiological parameters of a house with a high potential for internal and external exposures of the inhabitants. It was concluded that the epidemiological studies in a number of countries did not show any evidence of increased health detriment in HLNRAs compared to control groups. In this paper, the conclusions drawn from studies in some HLNRAs around the world in particular Ramsar are discussed. (author). 20 refs, 2 figs, 1 tab

  7. Protein space: a natural method for realizing the nature of protein universe.

    Science.gov (United States)

    Yu, Chenglong; Deng, Mo; Cheng, Shiu-Yuen; Yau, Shek-Chung; He, Rong L; Yau, Stephen S-T

    2013-02-07

    Current methods cannot tell us what the nature of the protein universe is concretely. They are based on different models of amino acid substitution and multiple sequence alignment which is an NP-hard problem and requires manual intervention. Protein structural analysis also gives a direction for mapping the protein universe. Unfortunately, now only a minuscule fraction of proteins' 3-dimensional structures are known. Furthermore, the phylogenetic tree representations are not unique for any existing tree construction methods. Here we develop a novel method to realize the nature of protein universe. We show the protein universe can be realized as a protein space in 60-dimensional Euclidean space using a distance based on a normalized distribution of amino acids. Every protein is in one-to-one correspondence with a point in protein space, where proteins with similar properties stay close together. Thus the distance between two points in protein space represents the biological distance of the corresponding two proteins. We also propose a natural graphical representation for inferring phylogenies. The representation is natural and unique based on the biological distances of proteins in protein space. This will solve the fundamental question of how proteins are distributed in the protein universe. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. SPACE RADIATION ENVIRONMENT MONITORED BY KITSAT-1 AND KITSAT-2

    Directory of Open Access Journals (Sweden)

    Y. H. Shin

    1996-06-01

    Full Text Available The results of space radiation experiments carried out on board the first two Korean technology demonstration microsatellites are presented in this paper. The first satellite, KITSAT-1, launched in August 1992, carries a radiation monitoring payload called cosmic ray experiment(CRE for characterizing the low-earth orbit(LEO radiation environment. The CRE consists of two sub-systems: the cosmic particle experiment (CPE and the total dose experiment(TDE. In addition, single event upset(SEUrates of the program memory and the RAM disk are also monitored. The second satellite, KITSAT-2, launched in September 1993, carries a newly developed 32-bit on-board computer(OBC, KASCOM(KAIST satellite computer in addition to OBC186. SEUs ocurred in the KASCOM, as well as in the program memory and RAM disk memory, have been monitored since the beginning of the satellite operation. These two satellites, which are very similar in structures but different in orbits, provide a unique opportunity to study the effects of the radiation environment characterized by the orbit.

  9. The Effects of Radiation on Imagery Sensors in Space

    Science.gov (United States)

    Mathis, Dylan

    2007-01-01

    Recent experience using high definition video on the International Space Station reveals camera pixel degradation due to particle radiation to be a much more significant problem with high definition cameras than with standard definition video. Although it may at first appear that increased pixel density on the imager is the logical explanation for this, the ISS implementations of high definition suggest a more complex causal and mediating factor mix. The degree of damage seems to vary from one type of camera to another, and this variation prompts a reconsideration of the possible factors in pixel loss, such as imager size, number of pixels, pixel aperture ratio, imager type (CCD or CMOS), method of error correction/concealment, and the method of compression used for recording or transmission. The problem of imager pixel loss due to particle radiation is not limited to out-of-atmosphere applications. Since particle radiation increases with altitude, it is not surprising to find anecdotal evidence that video cameras subject to many hours of airline travel show an increased incidence of pixel loss. This is even evident in some standard definition video applications, and pixel loss due to particle radiation only stands to become a more salient issue considering the continued diffusion of high definition video cameras in the marketplace.

  10. Radiation safety standards: space hazards vs. terrestrial hazards

    International Nuclear Information System (INIS)

    Sinclair, W.K.

    1983-01-01

    Policies regarding the setting of standards for radiation exposure for astronauts and other workers in space are discussed. The first recommendations for dose limitation and the underlying philosophy of these recommendations, which were put out in 1970, are examined, and consequences for the standards if the same philosophy of allowing a doubling in overall cancer risk for males aged 30-35 over a 20-year period were applied to more recent risk estimates are calculated, leading to values about a factor of 4 below the 1970 recommendation. Standards set since 1930 for terrestrial occupational exposures, which lead to a maximum lifetime risk of about 2.3 percent, are then considered, and the space and terrestrial exposure risks for fatal cancers at maximum lifetime dose are compared with industrial accidental death rates. Attention is also given to the question of the potential effects of HZE particles in space and to the possibility that HZE particle effects, rather than radiation carcinogenesis, might be the limiting factor. 17 references

  11. Population doses from naturally occurring radiation in Norway

    International Nuclear Information System (INIS)

    Stranden, E.

    The main purpose of this work was to study the radiological consequences of the introduction of building materials with high concentrations of radioactivity and to analyse the impact of a reduction of the ventilation rates in houses on the population dose from inhalation of natural airborne radioactivity. The general problems of radioactivity in building materials are discussed. Measurements of radioactivity in building materials from different parts of the country are reported, together with theoretical calculations of the gamma doses in houses. These calculations are compared with experimental results and earlier measurements of the indoor gamma radiation in Norway. Measurements of the outdoor gamma radiation in different parts of Norway are presented. These results are used together with earlier measurements of the gamma radiation inside houses to calculate the average, and variations of population dose from this radiation. An experimental study on the radon concentrations inside different types of dwellings, and a discussion of the respiratory dose received by the inhalation of radon daughters is presented. Some factors that may have influence upon the radon concentrations are also discussed. A method for measurement of radon and thoron daughters in air is discussed. The possible radiological effects of an increased radon concentration in houses are discussed. (Auth.)

  12. Photoluminescence in large fluence radiation irradiated space silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Hisamatsu, Tadashi; Kawasaki, Osamu; Matsuda, Sumio [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan). Tsukuba Space Center; Tsukamoto, Kazuyoshi

    1997-03-01

    Photoluminescence spectroscopy measurements were carried out for silicon 50{mu}m BSFR space solar cells irradiated with 1MeV electrons with a fluence exceeding 1 x 10{sup 16} e/cm{sup 2} and 10MeV protons with a fluence exceeding 1 x 10{sup 13} p/cm{sup 2}. The results were compared with the previous result performed in a relative low fluence region, and the radiation-induced defects which cause anomalous degradation of the cell performance in such large fluence regions were discussed. As far as we know, this is the first report which presents the PL measurement results at 4.2K of the large fluence radiation irradiated silicon solar cells. (author)

  13. The transition radiation detector of the PAMELA space mission

    Science.gov (United States)

    Ambriola, M.; Bellotti, R.; Cafagna, F.; Circella, M.; de Marzo, C.; Giglietto, N.; Marangelli, B.; Mirizzi, N.; Romita, M.; Spinelli, P.

    2004-04-01

    PAMELA space mission objective is to flight a satellite-borne magnetic spectrometer built to fulfill the primary scientific goals of detecting antiparticles (antiprotons and positrons) and to measure spectra of particles in cosmic rays. The PAMELA telescope is composed of: a silicon tracker housed in a permanent magnet, a time-of-flight and an anticoincidence system both made of plastic scintillators, a silicon imaging calorimeter, a neutron detector and a Transition Radiation Detector (TRD). The TRD is composed of nine sensitive layers of straw tubes working in proportional mode for a total of 1024 channels. Each layer is interleaved with a radiator plane made of carbon fibers. The TRD characteristics will be described along with its performances studied at both CERN-PS and CERN-SPS facilities, using electrons, pions, muons and protons of different momenta.

  14. The transition radiation detector of the PAMELA space mission

    International Nuclear Information System (INIS)

    Ambriola, M.; Bellotti, R.; Cafagna, F.; Circella, M.; De Marzo, C.; Giglietto, N.; Marangelli, B.; Mirizzi, N.; Romita, M.; Spinelli, P.

    2004-01-01

    PAMELA space mission objective is to flight a satellite-borne magnetic spectrometer built to fulfill the primary scientific goals of detecting antiparticles (antiprotons and positrons) and to measure spectra of particles in cosmic rays. The PAMELA telescope is composed of: a silicon tracker housed in a permanent magnet, a time-of-flight and an anticoincidence system both made of plastic scintillators, a silicon imaging calorimeter, a neutron detector and a Transition Radiation Detector (TRD). The TRD is composed of nine sensitive layers of straw tubes working in proportional mode for a total of 1024 channels. Each layer is interleaved with a radiator plane made of carbon fibers. The TRD characteristics will be described along with its performances studied at both CERN-PS and CERN-SPS facilities, using electrons, pions, muons and protons of different momenta

  15. Next Generation Radiation Hard IMM Space Solar Cells

    Directory of Open Access Journals (Sweden)

    Sharps P.

    2017-01-01

    Full Text Available High efficiency space solar cells based on the GaInP2/InGaAs/Ge triple junction lattice matched device with 1 sun, AM0 efficiencies of approximately 30% are commercially available from several companies. Multiple approaches have been suggested for significantly surpassing the 30% efficiency level, but achieving this in a commercially viable cell has not been easy. We review those approaches, pointing out the advantages and challenges of each. SolAero has been focused on developing the inverted metamorphic multi-junction (IMM solar cell, and has recently demonstrated a radiation hard version. We present the most recent performance data, including the response to particle radiation. The IMM cell can be used in a number of rigid or flexible configurations, and considerable effort has been focused on cell packaging and panel integration. The IMM device is ready to start qualification to the ECSS and AIAA standards.

  16. Radiation resistance of solar cells for space application, 1

    International Nuclear Information System (INIS)

    Mitsui, Hiroshi; Tanaka, Ryuichi; Sunaga, Hiromi

    1989-07-01

    A 50-μm thick ultrathin silicon solar cell and a 280-μm thick high performance AlGaAs/GaAs solar cell with high radiation resistance have been recently developed by National Space Development Agency of Japan (NASDA). In order to study the radiation resistance of these cells, a joint research was carried out between Japan Atomic Energy Research Institute (JAERI) and NASDA from 1984 through 1987. In this research, the irradiation method of electron beams, the effects of the irradiation conditions on the deterioration of solar cells by electron beams, and the annealing effects of the radiation damage in solar cells were investigated. This paper is the first one of a series of reports of the joint research. In this paper, the space radiation environment which artificial satellites will encounter, the solar cells used, and the experimental methods are described. In addition to these, the results of the study on the irradiation procedure of electron beams are reported. In the study of the irradiation method of electron beams, three methods, that is, the fixed irradiation method, the moving irradiation method, and the spot irradiation method were examined. In the fixed irradiation method and moving one, stationary solar cells and solar cells moving by conveyer were irradiated by scanning electron beams, respectively. On the other hand, in the spot irradiation method, stationary solar cells were irradiated by non-scanning steady electron beams. It was concluded that the fixed irradiation method was the most proper method. In addition to this, in this study, some pieces of information were obtained with respect to the changes in the electrical characteristics of solar cells caused by the irradiation of electron beams. (author) 52 refs

  17. Radiation dose assessments for materials with elevated natural radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Markkanen, M.

    1995-11-01

    The report provides practical information needed for evaluating the radiation dose to the general public and workers caused by materials containing elevated levels of natural radionuclides. The report presents criteria, exposure scenarios and calculations used to assess dose with respect to the safety requirements set for construction materials in accordance with the Finnish Radiation Act. A method for calculating external gamma exposure from building materials is presented in detail. The results for most typical cases are given as specific dose rates in table form to enable doses to be assessed without computer calculation. A number of such dose assessments is presented, as is the corresponding computer code. Practical investigation levels for the radioactivity of materials are defined. (23 refs.).

  18. Extractable protein content of radiation vulcanized natural rubber latex films

    International Nuclear Information System (INIS)

    Ma'zam Md Said; Wan Manshol Wan Zin

    1996-01-01

    The effects of processing conditions on extractable protein content of coagulant dipped radiation vulcanized natural rubber latex films have been investigated. Drying of wet-gel of radiation vulcanized latex films even at a relatively low temperature of 70 degree C resulted in increases of extractable protein content of the films. The extractable protein content is dependent upon both the temperature and time of drying of wet-gel deposit. Wet-gel leaching of film alone is not adequate to reduce the extractable protein content of films to low levels. Combination of wet-gel leaching, post-leaching, a dip in corn starch slurry, followed by drying at a low temperature of 70 degree C reduces the extractable protein content of films to very low levels

  19. Prospects of using natural antioxidants in radiation processed food

    International Nuclear Information System (INIS)

    Kanatt, S.R.; Chander, Ramesh; Sharma, Arun

    2006-01-01

    Full text: Microbial contamination of food is a serious concern both for food producer and consumer. Radiation processing of food is one of the most effective technologies that can extend the shelf-life and eliminate pathogenic bacteria in food. However, wide acceptability of radiation processed food products will depend upon quality parameters such as oxidative changes, color stability and organoleptic attributes. Any food processing technique is known to accelerate lipid peroxidation and radiation processing is no exception. Irradiation does not adversely affect the overall nutritive value of food and the oxidative changes induced by irradiation are similar to those observed using conventional food processing methods. Combination of various processing conditions such as storage and cooking, results in accelerated oxidative deterioration. The growing demand for convenience foods and the evolving markets for pre cooked food, call for techniques to prevent lipid oxidation in prepared stored food. Products of lipid peroxidation adversely affect the color, flavor and texture of the food. It is therefore necessary to control these changes for better product development. Methods commonly employed by the food industry include the use of antioxidants. Presently, most of the antioxidants used are synthetic but consumer concern has become a driving force for exploring the use of natural antioxidants. The increase interest in substitution of synthetic antioxidants with natural antioxidants has fostered research on screening of plant materials in order to identify new compounds. We have investigated the antioxidant potential of several plant extracts, herbs and waste generated by the food industry, such as potato peel, banana peel, mango peel, mint, cinnamon extracts and chitosan. Mint extract was found to have the maximum antioxidant activity as tested by several in vitro antioxidant assays. The antioxidant activity of mint extract was comparable to that of BHT the commonly

  20. Nature of Medical Malpractice Claims Against Radiation Oncologists.

    Science.gov (United States)

    Marshall, Deborah; Tringale, Kathryn; Connor, Michael; Punglia, Rinaa; Recht, Abram; Hattangadi-Gluth, Jona

    2017-05-01

    To examine characteristics of medical malpractice claims involving radiation oncologists closed during a 10-year period. Malpractice claims filed against radiation oncologists from 2003 to 2012 collected by a nationwide liability insurance trade association were analyzed. Outcomes included the nature of claims and indemnity payments, including associated presenting diagnoses, procedures, alleged medical errors, and injury severity. We compared the likelihood of a claim resulting in payment in relation to injury severity categories (death as referent) using binomial logistic regression. There were 362 closed claims involving radiation oncology, 102 (28%) of which were paid, resulting in $38 million in indemnity payments. The most common alleged errors included "improper performance" (38% of closed claims, 18% were paid; 29% [$11 million] of total indemnity), "errors in diagnosis" (25% of closed claims, 46% were paid; 44% [$17 million] of total indemnity), and "no medical misadventure" (14% of closed claims, 8% were paid; less than 1% [$148,000] of total indemnity). Another physician was named in 32% of claims, and consent issues/breach of contract were cited in 18%. Claims for injury resulting in death represented 39% of closed claims and 25% of total indemnity. "Improper performance" was the primary alleged error associated with injury resulting in death. Compared with claims involving death, major temporary injury (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.29-5.85, P=.009), significant permanent injury (OR 3.1, 95% CI 1.48-6.46, P=.003), and major permanent injury (OR 5.5, 95% CI 1.89-16.15, P=.002) had a higher likelihood of a claim resulting in indemnity payment. Improper performance was the most common alleged malpractice error. Claims involving significant or major injury were more likely to be paid than those involving death. Insights into the nature of liability claims against radiation oncologists may help direct efforts to improve quality of care

  1. A new system for the measurement of the space radiation

    International Nuclear Information System (INIS)

    Pazmandi, T.; Apathy, I.; Deme, S.; Beaujean, R.

    2000-01-01

    Radiation from space mainly consists of charged heavy particles (protons and heavier particles). Due to this fact, the effective dose significantly differs from the physical dose. Current measuring equipment is not fully suitable to measure both of the quantities simultaneously. A combined device for measurement of the mentioned values consists of an on-board thermoluminescence dosimeter reader and a three-axis silicon detector linear energy transfer spectrometer. This paper deals with the main characteristic of the new system. This system can be, applied for dosimetry of air crew as well. (authors)

  2. A new system for measurement of the space radiation

    International Nuclear Information System (INIS)

    Pazmandi, T.; Apathy, I.; Deme, S.; Beaujean, R.

    2001-01-01

    The space radiation mainly consists of heavy charged particles (protons and heavier particles). Due to this fact its effective dose significantly differs from the physical dose. The recently used measuring equipment is not fully suitable to measure both quantities simultaneously. The combined device for measurement of mentioned values consists of an on board thermoluminescent dosimeter reader and a three axis silicon telescope as a linear energy transfer spectrometer. The paper deals with the main characteristics of the new system. This system can be applied for dosimetry of air-crew as well. (authors)

  3. The Los Alamos dynamic radiation environment assimilation model (DREAM) for space weather specification and forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Reeves, Geoffrey D [Los Alamos National Laboratory; Friedel, Reiner H W [Los Alamos National Laboratory; Chen, Yue [Los Alamos National Laboratory; Koller, Josef [Los Alamos National Laboratory; Henderson, Michael G [Los Alamos National Laboratory

    2008-01-01

    The Dynamic Radiation Environment Assimilation Model (DREAM) was developed at Los Alamos National Laboratory to assess, quantify, and predict the hazards from the natural space environment and the anthropogenic environment produced by high altitude nuclear explosions (HANE). DREAM was initially developed as a basic research activity to understand and predict the dynamics of the Earth's Van Allen radiation belts. It uses Kalman filter techniques to assimilate data from space environment instruments with a physics-based model of the radiation belts. DREAM can assimilate data from a variety of types of instruments and data with various levels of resolution and fidelity by assigning appropriate uncertainties to the observations. Data from any spacecraft orbit can be assimilated but DREAM was designed to function with as few as two spacecraft inputs: one from geosynchronous orbit and one from GPS orbit. With those inputs, DREAM can be used to predict the environment at any satellite in any orbit whether space environment data are available in those orbits or not. Even with very limited data input and relatively simple physics models, DREAM specifies the space environment in the radiation belts to a high level of accuracy. DREAM has been extensively tested and evaluated as we transition from research to operations. We report here on one set of test results in which we predict the environment in a highly-elliptical polar orbit. We also discuss long-duration reanalysis for spacecraft design, using DREAM for real-time operations, and prospects for 1-week forecasts of the radiation belt environment.

  4. Genetic susceptibility: radiation effects relevant to space travel.

    Science.gov (United States)

    Peng, Yuanlin; Nagasawa, Hatsumi; Warner, Christy; Bedford, Joel S

    2012-11-01

    Genetic variation in the capacity to repair radiation damage is an important factor influencing both cellular and tissue radiosensitivity variation among individuals as well as dose rate effects associated with such damage. This paper consists of two parts. The first part reviews some of the available data relating to genetic components governing such variability among individuals in susceptibility to radiation damage relevant for radiation protection and discusses the possibility and extent to which these may also apply for space radiations. The second part focuses on the importance of dose rate effects and genetic-based variations that influence them. Very few dose rate effect studies have been carried out for the kinds of radiations encountered in space. The authors present here new data on the production of chromosomal aberrations in noncycling low passage human ATM+/+ or ATM+/- cells following irradiations with protons (50 MeV or 1 GeV), 1 GeV(-1) n iron ions and gamma rays, where doses were delivered at a high dose rate of 700 mGy(-1) min, or a lower dose rate of 5 mGy min(-1). Dose responses were essentially linear over the dose ranges tested and not significantly different for the two cell strains. Values of the dose rate effectiveness factor (DREF) were expressed as the ratio of the slopes of the dose-response curves for the high versus the lower (5 mGy min(-1)) dose rate exposures. The authors refer to this as the DREF5. For the gamma ray standard, DREF5 values of approximately two were observed. Similar dose rate effects were seen for both energies of protons (DREF5 ≈ 2.2 in both cases). For 1 GeV(-1) n iron ions [linear energy transfer (LET) ≈ 150 keV μ(-1)], the DREF5 was not 1 as might have been expected on the basis of LET alone but was approximately 1.3. From these results and conditions, the authors estimate that the relative biological effectiveness for 1 GeV(-1) n iron ions for high and low dose rates, respectively, were about 10 and 15

  5. Radiation Physics for Space and High Altitude Air Travel

    Science.gov (United States)

    Cucinotta, F. A.; Wilson, J. W.; Goldhagen, P.; Saganti, P.; Shavers, M. R.; McKay, Gordon A. (Technical Monitor)

    2000-01-01

    Galactic cosmic rays (GCR) are of extra-solar origin consisting of high-energy hydrogen, helium, and heavy ions. The GCR are modified by physical processes as they traverse through the solar system, spacecraft shielding, atmospheres, and tissues producing copious amounts of secondary radiation including fragmentation products, neutrons, mesons, and muons. We discuss physical models and measurements relevant for estimating biological risks in space and high-altitude air travel. Ambient and internal spacecraft computational models for the International Space Station and a Mars mission are discussed. Risk assessment is traditionally based on linear addition of components. We discuss alternative models that include stochastic treatments of columnar damage by heavy ion tracks and multi-cellular damage following nuclear fragmentation in tissue.

  6. Space experiment "Cellular Responses to Radiation in Space (CELLRAD)": Hardware and biological system tests

    Science.gov (United States)

    Hellweg, Christine E.; Dilruba, Shahana; Adrian, Astrid; Feles, Sebastian; Schmitz, Claudia; Berger, Thomas; Przybyla, Bartos; Briganti, Luca; Franz, Markus; Segerer, Jürgen; Spitta, Luis F.; Henschenmacher, Bernd; Konda, Bikash; Diegeler, Sebastian; Baumstark-Khan, Christa; Panitz, Corinna; Reitz, Günther

    2015-11-01

    One factor contributing to the high uncertainty in radiation risk assessment for long-term space missions is the insufficient knowledge about possible interactions of radiation with other spaceflight environmental factors. Such factors, e.g. microgravity, have to be considered as possibly additive or even synergistic factors in cancerogenesis. Regarding the effects of microgravity on signal transduction, it cannot be excluded that microgravity alters the cellular response to cosmic radiation, which comprises a complex network of signaling pathways. The purpose of the experiment ;Cellular Responses to Radiation in Space; (CELLRAD, formerly CERASP) is to study the effects of combined exposure to microgravity, radiation and general space flight conditions on mammalian cells, in particular Human Embryonic Kidney (HEK) cells that are stably transfected with different plasmids allowing monitoring of proliferation and the Nuclear Factor κB (NF-κB) pathway by means of fluorescent proteins. The cells will be seeded on ground in multiwell plate units (MPUs), transported to the ISS, and irradiated by an artificial radiation source after an adaptation period at 0 × g and 1 × g. After different incubation periods, the cells will be fixed by pumping a formaldehyde solution into the MPUs. Ground control samples will be treated in the same way. For implementation of CELLRAD in the Biolab on the International Space Station (ISS), tests of the hardware and the biological systems were performed. The sequence of different steps in MPU fabrication (cutting, drilling, cleaning, growth surface coating, and sterilization) was optimized in order to reach full biocompatibility. Different coatings of the foil used as growth surface revealed that coating with 0.1 mg/ml poly-D-lysine supports cell attachment better than collagen type I. The tests of prototype hardware (Science Model) proved its full functionality for automated medium change, irradiation and fixation of cells. Exposure of

  7. The NASA Space Radiation Laboratory at Brookhaven National Laboratory: Preparation and delivery of ion beams for space radiation research

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Kevin; Ahrens, Leif; Hung Chiang, I; Gardner, Christopher; Gassner, David; Hammons, Lee; Harvey, Margaret; Kling, Nicholas; Morris, John; Pile, Phillip; Rusek, Adam; Sivertz, Mike, E-mail: sivertz@bnl.gov; Steski, Dannie; Tsoupas, Nick; Zeno, Keith

    2010-06-21

    The NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL) was commissioned in October 2002 and became operational in July 2003. The NSRL was constructed in collaboration with NASA for the purpose of performing space radiation research as part of the NASA space program. The NSRL can accept a wide variety of ions from BNL's Collider Accelerator Department (CAD) Booster accelerator. These ion beams are extracted from the accelerator with kinetic energies ranging from 0.05 to 3 GeV/nucleon. Many different beam conditions have been produced for experiments at NSRL. The facilities at BNL and the design of the NSRL facility permit a wide variety of beams to be produced with a great degree of flexibility in the delivery of ion beams to experiments. In this report we will describe the facility and its performance over the eight experimental run periods that have taken place since it became operational. We will also describe the current and future capabilities of the NSRL.

  8. Radiation shielding properties of some natural rocks in upper Egypt

    International Nuclear Information System (INIS)

    Abbady, A.; Ahmed, N.K.; Saied, M.H.; Uosif, M.A.; El-kamel, A.H.

    1999-01-01

    To support the use of some natural rocks in Upper Egypt as suitable radiation materials, the attenuation of gamma - ray through destructive and nondestructive samples of alabaster, marble and limestone have been tested in the energy range from 356 keV to 1173 keV. The attenuation coefficients of the nondestructive samples are found higher than the values of the destructive samples. The half - layer values for attenuation, and the concentration of uranium and thorium in the samples were calculated and discussed

  9. Genetic damage from low-level and natural background radiation

    International Nuclear Information System (INIS)

    Oftedal, P.

    1988-01-01

    Relevant predictions that have been made of possible low level biological effects on man are reviewed, and the estimate of genetic damage is discussed. It is concluded that in spite of a number of attempts, no clear-cut case of effects in human populations of radiation at natural levels has been demonstrated. The stability of genetic material is dynamic, with damage, repair and selection running as continuous processes. Genetic materials are well protected and are conservative in the extreme, not least because evolution by genetic adaptation is an expensive process: Substitution of one allele A 1 by another A 2 means the death of the whole A 1 population

  10. Space radiation risks for astronauts on multiple International Space Station missions.

    Directory of Open Access Journals (Sweden)

    Francis A Cucinotta

    Full Text Available Mortality and morbidity risks from space radiation exposure are an important concern for astronauts participating in International Space Station (ISS missions. NASA's radiation limits set a 3% cancer fatality probability as the upper bound of acceptable risk and considers uncertainties in risk predictions using the upper 95% confidence level (CL of the assessment. In addition to risk limitation, an important question arises as to the likelihood of a causal association between a crew-members' radiation exposure in the past and a diagnosis of cancer. For the first time, we report on predictions of age and sex specific cancer risks, expected years of life-loss for specific diseases, and probability of causation (PC at different post-mission times for participants in 1-year or multiple ISS missions. Risk projections with uncertainty estimates are within NASA acceptable radiation standards for mission lengths of 1-year or less for likely crew demographics. However, for solar minimum conditions upper 95% CL exceed 3% risk of exposure induced death (REID by 18 months or 24 months for females and males, respectively. Median PC and upper 95%-confidence intervals are found to exceed 50% for several cancers for participation in two or more ISS missions of 18 months or longer total duration near solar minimum, or for longer ISS missions at other phases of the solar cycle. However, current risk models only consider estimates of quantitative differences between high and low linear energy transfer (LET radiation. We also make predictions of risk and uncertainties that would result from an increase in tumor lethality for highly ionizing radiation reported in animal studies, and the additional risks from circulatory diseases. These additional concerns could further reduce the maximum duration of ISS missions within acceptable risk levels, and will require new knowledge to properly evaluate.

  11. Space radiation risks for astronauts on multiple International Space Station missions.

    Science.gov (United States)

    Cucinotta, Francis A

    2014-01-01

    Mortality and morbidity risks from space radiation exposure are an important concern for astronauts participating in International Space Station (ISS) missions. NASA's radiation limits set a 3% cancer fatality probability as the upper bound of acceptable risk and considers uncertainties in risk predictions using the upper 95% confidence level (CL) of the assessment. In addition to risk limitation, an important question arises as to the likelihood of a causal association between a crew-members' radiation exposure in the past and a diagnosis of cancer. For the first time, we report on predictions of age and sex specific cancer risks, expected years of life-loss for specific diseases, and probability of causation (PC) at different post-mission times for participants in 1-year or multiple ISS missions. Risk projections with uncertainty estimates are within NASA acceptable radiation standards for mission lengths of 1-year or less for likely crew demographics. However, for solar minimum conditions upper 95% CL exceed 3% risk of exposure induced death (REID) by 18 months or 24 months for females and males, respectively. Median PC and upper 95%-confidence intervals are found to exceed 50% for several cancers for participation in two or more ISS missions of 18 months or longer total duration near solar minimum, or for longer ISS missions at other phases of the solar cycle. However, current risk models only consider estimates of quantitative differences between high and low linear energy transfer (LET) radiation. We also make predictions of risk and uncertainties that would result from an increase in tumor lethality for highly ionizing radiation reported in animal studies, and the additional risks from circulatory diseases. These additional concerns could further reduce the maximum duration of ISS missions within acceptable risk levels, and will require new knowledge to properly evaluate.

  12. Spaceflight Radiation Health program at the Lyndon B. Johnson Space Center

    International Nuclear Information System (INIS)

    Johnson, A.S.; Badhwar, G.D.; Golightly, M.J.; Hardy, A.C.; Konradi, A.; Yang, T.C.

    1993-12-01

    The Johnson Space Center leads the research and development activities that address the health effects of space radiation exposure to astronaut crews. Increased knowledge of the composition of the environment and of the biological effects of space radiation is required to assess health risks to astronaut crews. The activities at the Johnson Space Center range from quantification of astronaut exposures to fundamental research into the biological effects resulting from exposure to high energy particle radiation. The Spaceflight Radiation Health Program seeks to balance the requirements for operational flexibility with the requirement to minimize crew radiation exposures. The components of the space radiation environment are characterized. Current and future radiation monitoring instrumentation is described. Radiation health risk activities are described for current Shuttle operations and for research development program activities to shape future analysis of health risk

  13. Hawking radiation from black holes in de Sitter spaces

    International Nuclear Information System (INIS)

    Jiang Qingquan

    2007-01-01

    Recently, Hawking radiation has been treated, by Robinson and Wilczek (2005 Phys. Rev. Lett. 95 011303), as a compensating flux of the energy-momentum tensor required to cancel a gravitational anomaly at the event horizon (EH) of a Schwarzschild-type black hole. In this paper, motivated by this work, Hawking radiation from the event horizon (EH) and the de Sitter cosmological horizon (CH) of black holes in de Sitter spaces, specifically including the purely de Sitter black hole and the static, spherically symmetric Schwarzschild-de Sitter black hole as well as the rotating Kerr-de Sitter black hole, have been studied by anomalies. The results show that the gauge-current and energy-momentum tensor fluxes, required to restore gauge invariance and general coordinate covariance at the EH and the CH, are precisely equal to those of Hawking radiation from the EH and the CH, respectively. It should be noted that gauge and gravitational anomalies taking place at the CH arise from the fact that the effective field theory is formulated inside the CH to integrate out the classically irrelevant outgoing modes at the CH, which are different from those at the black hole horizon

  14. Space radiation absorbed dose distribution in a human phantom

    Science.gov (United States)

    Badhwar, G. D.; Atwell, W.; Badavi, F. F.; Yang, T. C.; Cleghorn, T. F.

    2002-01-01

    The radiation risk to astronauts has always been based on measurements using passive thermoluminescent dosimeters (TLDs). The skin dose is converted to dose equivalent using an average radiation quality factor based on model calculations. The radiological risk estimates, however, are based on organ and tissue doses. This paper describes results from the first space flight (STS-91, 51.65 degrees inclination and approximately 380 km altitude) of a fully instrumented Alderson Rando phantom torso (with head) to relate the skin dose to organ doses. Spatial distributions of absorbed dose in 34 1-inch-thick sections measured using TLDs are described. There is about a 30% change in dose as one moves from the front to the back of the phantom body. Small active dosimeters were developed specifically to provide time-resolved measurements of absorbed dose rates and quality factors at five organ locations (brain, thyroid, heart/lung, stomach and colon) inside the phantom. Using these dosimeters, it was possible to separate the trapped-proton and the galactic cosmic radiation components of the doses. A tissue-equivalent proportional counter (TEPC) and a charged-particle directional spectrometer (CPDS) were flown next to the phantom torso to provide data on the incident internal radiation environment. Accurate models of the shielding distributions at the site of the TEPC, the CPDS and a scalable Computerized Anatomical Male (CAM) model of the phantom torso were developed. These measurements provided a comprehensive data set to map the dose distribution inside a human phantom, and to assess the accuracy and validity of radiation transport models throughout the human body. The results show that for the conditions in the International Space Station (ISS) orbit during periods near the solar minimum, the ratio of the blood-forming organ dose rate to the skin absorbed dose rate is about 80%, and the ratio of the dose equivalents is almost one. The results show that the GCR model dose

  15. Quantum Signature of Analog Hawking Radiation in Momentum Space.

    Science.gov (United States)

    Boiron, D; Fabbri, A; Larré, P-É; Pavloff, N; Westbrook, C I; Ziń, P

    2015-07-10

    We consider a sonic analog of a black hole realized in the one-dimensional flow of a Bose-Einstein condensate. Our theoretical analysis demonstrates that one- and two-body momentum distributions accessible by present-day experimental techniques provide clear direct evidence (i) of the occurrence of a sonic horizon, (ii) of the associated acoustic Hawking radiation, and (iii) of the quantum nature of the Hawking process. The signature of the quantum behavior persists even at temperatures larger than the chemical potential.

  16. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    International Nuclear Information System (INIS)

    Hendry, Jolyon H; Sohrabi, Mehdi; Burkart, Werner; Simon, Steven L; Wojcik, Andrzej; Cardis, Elisabeth; Laurier, Dominique; Tirmarche, Margot; Hayata, Isamu

    2009-01-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222 Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case-control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case-control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

  17. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    Energy Technology Data Exchange (ETDEWEB)

    Hendry, Jolyon H; Sohrabi, Mehdi; Burkart, Werner [Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna (Austria); Simon, Steven L [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD (United States); Wojcik, Andrzej [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Cardis, Elisabeth [Centre for Research in Environmental Epidemiology (CREAL), Municipal Institute of Medical Research (IMIM-Hospital del Mar) and CIBER Epidemiologia y Salud Publica - CIBERESP, Barcelona (Spain); Laurier, Dominique; Tirmarche, Margot [Radiobiology and Epidemiology Department, Radiological and Human Health Division, Institute for Radiological Protection and Nuclear Safety, Fontenay-aux-Roses (France); Hayata, Isamu [National Institute of Radiological Sciences, Chiba (Japan)], E-mail: jhendry2002uk@yahoo.com

    2009-06-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of {sup 222}Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case-control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case-control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

  18. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    Science.gov (United States)

    Hendry, Jolyon H; Simon, Steven L; Wojcik, Andrzej; Sohrabi, Mehdi; Burkart, Werner; Cardis, Elisabeth; Laurier, Dominique; Tirmarche, Margot; Hayata, Isamu

    2014-01-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case–control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case–control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors. PMID:19454802

  19. Human Research Program Space Radiation Standing Review Panel (SRP)

    Science.gov (United States)

    Woloschak, Gayle; Steinberg-Wright, S.; Coleman, Norman; Grdina, David; Hill, Colin; Iliakis, George; Metting, Noelle; Meyers, Christina

    2010-01-01

    The Space Radiation Standing Review Panel (SRP) met at the NASA Johnson Space Center (JSC) on December 9-11, 2009 to discuss the areas of current and future research targeted by the Space Radiation Program Element (SRPE) of the Human Research Program (HRP). Using evidence-based knowledge as a background for identified risks to astronaut health and performance, NASA had identified gaps in knowledge to address those risks. Ongoing and proposed tasks were presented to address the gaps. The charge to the Space Radiation SRP was to review the gaps, evaluate whether the tasks addressed these gaps and to make recommendations to NASA s HRP Science Management Office regarding the SRP's review. The SRP was requested to evaluate the practicality of the proposed efforts in light of the demands placed on the HRP. Several presentations were made to the SRP during the site visit and the SRP spent sufficient time to address the SRP charge. The SRP made a final debriefing to the HRP Program Scientist, Dr. John B. Charles, on December 11, 2009. The SRP noted that current SRPE strategy is properly science-based and views this as the best assurance of the likelihood that answers to the questions posed as gaps in knowledge can be found, that the uncertainty in risk estimates can be reduced, and that a solid, cost-effective approach to risk reduction solutions is being developed. The current approach of the SRPE, based on the use of carefully focused research solicitations, requiring thorough peer-review and approaches demonstrated to be on the path to answering the NASA strategic questions, addressed to a broad extramural community of qualified scientists, optimally positioned to take advantage of serendipitous discoveries and to leverage scientific advances made elsewhere, is sound and appropriate. The SRP viewed with concern statements by HRP implying that the only science legitimately deserving support should be "applied" or, in some instances that the very term "research" might be

  20. Dating method of Jomon pottery by utilizing natural radiation

    Energy Technology Data Exchange (ETDEWEB)

    Imai, Masahiko; Inokoshi, Yukio; Kitahara, Akiharu; Tanizaki, Yoshiyuki [Tokyo Metropolitan Isotope Research Center (Japan); Kamijo, Tomohiro

    1997-03-01

    ESR (Electron Spin Resonance) dating method using the signal induced by natural radiation was applied for the dating of Japanese prehistoric Pottery in TAMA Hill. About 100 mg of quartz was obtained from the shred of Pottery and ESR signal of Al center was observed. The obtained age of the pottery was older than that obtained from the charcoal excavated from the same site of the pottery by {sup 14}C method. The depth dependence of natural radiation ({gamma}-ray and cosmic ray) was measured by TLD (Thermoluminescence Dosimetry). At the depth less than 80 cm, the annual dose was somewhat more by the effect of cosmic ray than those at the depth more than 80 cm. Another dating method to measure the ESR signal of the quartz in the volcanic ash layer of Jomon period was examined. The obtained signal was too big to indicate Jomon age. Although the error is somewhat large, ESR dating method is concluded to be applicable for prehistoric pottery. (author)

  1. Evolution of organic molecules under Mars-like UV radiation conditions in space and laboratory

    Science.gov (United States)

    Rouquette, L.; Stalport, F.; Cottin, H.; Coll, P.; Szopa, C.; Saiagh, K.; Poch, O.; Khalaf, D.; Chaput, D.; Grira, K.; Dequaire, T.

    2017-09-01

    The detection and identification of organic molecules at Mars are of prime importance, as some of these molecules are life precursors and components. While in situ planetary missions are searching for them, it is essential to understand how organic molecules evolve and are preserved at the surface of Mars. Indeed the harsh conditions of the environment of Mars such as ultraviolet (UV) radiation or oxidative processes could explain the low abundance and diversity of organic molecules detected by now [1]. In order to get a better understanding of the evolution of organic matter at the surface of Mars, we exposed organic molecules under a Mars-like UV radiation environment. Similar organic samples were exposed to the Sun radiation, outside the International Space Station (ISS), and under a UV lamp (martian pressure and temperature conditions) in the laboratory. In both experiments, organic molecules tend to photodegrade under Mars-like UV radiation. Minerals, depending on their nature, can protect or accelerate the degradation of organic molecules. For some molecules, new products, possibly photoresistant, seem to be produced. Finally, experimenting in space allow us to get close to in situ conditions and to validate our laboratory experiment while the laboratory experiment is essential to study the evolution of a large amount and diversity of organic molecules.

  2. Postoperative residual pleural spaces: characteristics and natural history.

    Science.gov (United States)

    Misthos, Panagiotis; Kokotsakis, John; Konstantinou, Marios; Skottis, Ion; Lioulias, Achilles

    2007-01-01

    This study was conducted in order to re-define the incidence and natural history of postresectional residual pleural spaces (PRS). From 1997 to 2005, 966 patients who were subjected to less than entire lung resections, were followed and any cases of PRS were recorded. The records of these patients were retrospectively analyzed for age, gender, type of resection, side, apical or basal location, size, PRS wall thickness, empyema as well as for bronchopleural fistula occurence, management, and outcome. Postresectional residual pleural spaces outcome was correlated with space characteristics. A total of 92 cases (9.5%) of PRS were documented which developed frequently ( p 70 years ( p < 0.001), air leak ( p < 0.001), empyema ( p < 0.001), and thickened pleura ( p < 0.001). Good prognosis of PRS was strongly correlated with male gender, apical location, right side, normal pleura thickness, and small size. Postresectional residual pleural spaces of small size without any associated complications should not prolong hospitalization time.

  3. A New Active Space Radiation Instruments for the International Space Station, A-DREAMS

    Science.gov (United States)

    Uchihori, Yukio; Kodaira, Satoshi; Kitamura, Hisashi; Kobayashi, Shingo

    For future space experiments in the International Space Station (ISS) or other satellites, radiation detectors, A-DREAMS (Active Dosimeter for Radiation Environment and Astronautic Monitoring in Space), using single or multiple silicon semi-conductor detectors have been developed. The first version of the detectors were produced and calibrated with particle accelerators. National Institute of Radiological Sciences has a medical heavy ion accelerator (HIMAC) for cancer therapy and a cyclotron accelerator. The detector was irradiated with high energy heavy ions and protons in HIMAC and the cyclotron and calibrated the energy resolution and linearity for deposited energies of these particles. We are planned to be going to use the new instrument in an international project, the new MATROSHKA experiment which is directed by members in the Institute of Bio-Medical Problem (IBMP) in Russia and German Space Center (DLR) in Germany. In the project, the dose distribution in human torso phantom will be investigated for several months in the ISS. For the project, a new type of the instruments is under development in NIRS and the current situation will be reported in this paper.

  4. Regional environmental documentation of natural radiation in Sweden

    International Nuclear Information System (INIS)

    Wilson, C.

    1982-01-01

    In 1979, when the problem of high radon daughter levels in Swedish houses became widely published, the need for information on variations in the natural radiation environment became very apparent. The radon problem was at first attributed to radon emanation from alum shale based aerated concrete, but it was soon obvious that ground with an abnormally high uranium content constitutes an even greater risk for high radon daughter levels in houses. The geological Survey of Sweden was commissioned to produce a documentation in map form for all areas and rock types with gamma ray levels exceeding 30 μR/h, with the intention of delimiting risk areas for high soil gas radon contents. The maps, known as GEO-radiation maps, are produced at scale of 1:50 000. They are based primarily upon radiometric surveys, ground measurements of gammaradiation and geological mapping. To date some 450 map sheets have been published covering approximately 55% of the country. The maps provide primary information to local planning, health and building authorities as to variations in the natural radiation environment. Within the so-called risk areas marked on the maps, local authorities are recommended to investigate the soil gas radon content prior to any new development. Geological environments known, in Sweden, to be associated with radon daughter problems in dwellings are alum shale, a Cambrian, uranium-rich black shale, uranium-rich granites and uranium-rich pegmatites. Both alum shale and uranium-rich granites constitute extensive areas of bedrock. More recently it has been established that high soil-gas radon concentrations are also associated with glacial eskers. (Author)

  5. Positron annihilation lifetime study of radiation-damaged natural zircons

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, J. [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra (Australia); Gaugliardo, P. [Centre for Antimatter-Matter Studies, School of Physics, University of Western Australia (Australia); Farnan, I.; Zhang, M. [Department of Earth Sciences, University of Cambridge (United Kingdom); Vance, E.R.; Davis, J.; Karatchevtseva, I.; Knott, R.B. [Australian Nuclear Science and Technology Organisation (Australia); Mudie, S. [The Australian Synchrotron, Victoria (Australia); Buckman, S.J. [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra (Australia); Institute for Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Sullivan, J.P., E-mail: james.sullivan@anu.edu.au [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra (Australia)

    2016-04-01

    Zircons are a well-known candidate waste form for actinides and their radiation damage behaviour has been widely studied by a range of techniques. In this study, well-characterised natural single crystal zircons have been studied using Positron Annihilation Lifetime Spectroscopy (PALS). In some, but not all, of the crystals that had incurred at least half of the alpha-event damage of ∼10{sup 19} α/g required to render them structurally amorphous, PALS spectra displayed long lifetimes corresponding to voids of ∼0.5 nm in diameter. The long lifetimes corresponded to expectations from published Small-Angle X-ray Scattering data on similar samples. However, the non-observation by PALS of such voids in some of the heavily damaged samples may reflect large size variations among the voids such that no singular size can be distinguished or. Characterisation of a range of samples was also performed using scanning electron microscopy, optical absorption spectroscopy, Raman scattering and X-ray scattering/diffraction, with the degree of alpha damage being inferred mainly from the Raman technique and X-ray diffraction. The observed void diameters and intensities of the long lifetime components were changed somewhat by annealing at 700 °C; annealing at 1200 °C removed the voids entirely. The voids themselves may derive from He gas bubbles or voids created by the inclusion of small quantities of organic and hydrous matter, notwithstanding the observation that no voidage was evidenced by PALS in two samples containing hydrous and organic matter. - Highlights: • Study of a range of naturally occurring zircons damaged by alpha radiation. • Characterised using a range of techniques, including PALS spectroscopy. • Effects on hydrous material appear important, rather than direct radiation damage. • Annealing is shown to remove the observed voids.

  6. Radiation education by means of the measurement of natural environmental radiation in Tono region, Gifu prefecture

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Haruo; Yoshida, Yasuo [Plasma Research Committee of Toki, Gifu (Japan); Uda, Tatsuhiko; Obayashi, Haruo

    1999-09-01

    The Tono region is placed in the south-east of Gifu prefecture. In this region, there is a plan of construction of the Research and Education Park. As the center facility of the park, the National Institute for Fusion Science (NIFS) has started their research activities. The Plasma Research Committee of Toki-city has been organized by the board of education of Toki-city for about 20 years. The committee is mainly composed of science teachers of elementary school, junior high school and high school in the area. The committee has measured continuously the natural environmental background radiations in cooperation with NIFS. Its activities started before constructing the NIFS laboratory buildings. Now, the new measuring points in Tajimi-city and Mizunami-city are added to the points in Toki-city area, therefore, some teachers join as the new members of the committee. In this conference, we present. (1) Plasma Research Committee of Toki-city; its history, organization and activities. (2) Obtained data of the natural environmental radiation in Toki-city. (3) Example lecture taken in natural radiation, its results and the farther issues. (author)

  7. Radiation education by means of the measurement of natural environmental radiation in Tono region, Gifu prefecture

    International Nuclear Information System (INIS)

    Maruyama, Haruo; Yoshida, Yasuo; Uda, Tatsuhiko; Obayashi, Haruo

    1999-01-01

    The Tono region is placed in the south-east of Gifu prefecture. In this region, there is a plan of construction of the Research and Education Park. As the center facility of the park, the National Institute for Fusion Science (NIFS) has started their research activities. The Plasma Research Committee of Toki-city has been organized by the board of education of Toki-city for about 20 years. The committee is mainly composed of science teachers of elementary school, junior high school and high school in the area. The committee has measured continuously the natural environmental background radiations in cooperation with NIFS. Its activities started before constructing the NIFS laboratory buildings. Now, the new measuring points in Tajimi-city and Mizunami-city are added to the points in Toki-city area, therefore, some teachers join as the new members of the committee. In this conference, we present. (1) Plasma Research Committee of Toki-city; its history, organization and activities. (2) Obtained data of the natural environmental radiation in Toki-city. (3) Example lecture taken in natural radiation, its results and the farther issues. (author)

  8. On the role of natural radiation background in the initial development of plants

    International Nuclear Information System (INIS)

    Kuzin, A.M.; Vagabova, M.Eh.; Primak-Mirolyubov, V.N.

    1977-01-01

    To obtain data on plant development under strictly controlled decreased natural radiation conditions, the experiment with radish seeds was conducted in a special chamber having a decreased natural radiation background. It has been shown that the development of seedlings in the course of the first 4-5 days in significantly delayed, and it normalizes when radiation sources, imitating the natural radiation background, are placed inside the chamber

  9. Fall 2015 NASA Internship, and Space Radiation Health Project

    Science.gov (United States)

    Patience, Luke

    2015-01-01

    This fall, I was fortunate enough to have been able to participate in an internship at NASA's Lyndon B. Johnson Space Center. I was placed into the Human Health & Performance Directorate, where I was specifically tasked to work with Dr. Zarana Patel, researching the impacts of cosmic level radiation on human cells. Using different laboratory techniques, we were able to examine the cells to see if any damage had been done due to radiation exposure, and if so, how much damage was done. Cell culture samples were exposed at different doses, and fixed at different time points so that we could accumulate a large pool of quantifiable data. After examining quantifiable results relative to the impacts of space radiation on the human body at the cellular and chromosomal level, researchers can defer to different areas of the space program that have to do with astronaut safety, and research and development (extravehicular mobility unit construction, vehicle design and construction, etc.). This experience has been very eye-opening, and I was able to learn quite a bit. I learned some new laboratory techniques, and I did my best to try and learn new ways to balance such a hectic work and school schedule. I also learned some very intimate thing about working at NASA; I learned that far more people want to watch you succeed, rather than watch you fail, and I also learned that this is a place that is alive with innovators and explorers - people who have a sole purpose of exploring space for the betterment of humanity, and not for any other reason. It's truly inspiring. All of these experiences during my internship have impacted me in a really profound way, so much that my educational and career goals are completely different than when I started. I started out as a biotechnology major, and I discovered recently toward the end of the internship, that I don't want to work in a lab, nor was I as enthralled by biological life sciences as a believed myself to be. Taking that all into

  10. Neurobehavioral Effects of Space Radiation on Psychomotor Vigilance Tests

    Science.gov (United States)

    Hienz, Robert; Davis, Catherine; Weed, Michael; Guida, Peter; Gooden, Virginia; Brady, Joseph; Roma, Peter

    Neurobehavioral Effects of Space Radiation on Psychomotor Vigilance Tests INTRODUCTION Risk assessment of the biological consequences of living in the space radiation environment represents one of the highest priority areas of NASA radiation research. Of critical importance is the need for a risk assessment of damage to the central nervous system (CNS) leading to functional cognitive/behavioral changes during long-term space missions, and the development of effective shielding or biological countermeasures to such risks. The present research focuses on the use of an animal model that employs neurobehavioral tests identical or homologous to those currently in use in human models of risk assessment by U.S. agencies such as the Depart-ment of Defense and Federal Aviation and Federal Railroad Administrations for monitoring performance and estimating accident risks associated with such variables as fatigue and/or alcohol or drug abuse. As a first approximation for establishing human risk assessments due to exposure to space radiation, the present work provides animal performance data obtained with the rPVT (rat Psychomotor Vigilance Test), an animal analog of the human PVT that is currently employed for human risk assessments via quantification of sustained attention (e.g., 'vigilance' or 'readiness to perform' tasks). Ground-based studies indicate that radiation can induce neurobehavioral changes in rodents, including impaired performance on motor tasks and deficits in spatial learning and memory. The present study is testing the hypothesis that radiation exposure impairs motor function, performance accuracy, vigilance, motivation, and memory in adult male rats. METHODS The psychomotor vigilance test (PVT) was originally developed as a human cognitive neurobe-havioral assay for tracking the temporally dynamic changes in sustained attention, and has also been used to track changes in circadian rhythm. In humans the test requires responding to a small, bright

  11. Nature of Medical Malpractice Claims Against Radiation Oncologists

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Deborah; Tringale, Kathryn [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Connor, Michael [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); University of California Irvine School of Medicine, Irvine, California (United States); Punglia, Rinaa [Department of Radiation Oncology, Brigham and Women' s Hospital, Harvard Medical School, Boston, Massachusetts (United States); Recht, Abram [Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts (United States); Hattangadi-Gluth, Jona, E-mail: jhattangadi@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States)

    2017-05-01

    Purpose: To examine characteristics of medical malpractice claims involving radiation oncologists closed during a 10-year period. Methods and Materials: Malpractice claims filed against radiation oncologists from 2003 to 2012 collected by a nationwide liability insurance trade association were analyzed. Outcomes included the nature of claims and indemnity payments, including associated presenting diagnoses, procedures, alleged medical errors, and injury severity. We compared the likelihood of a claim resulting in payment in relation to injury severity categories (death as referent) using binomial logistic regression. Results: There were 362 closed claims involving radiation oncology, 102 (28%) of which were paid, resulting in $38 million in indemnity payments. The most common alleged errors included “improper performance” (38% of closed claims, 18% were paid; 29% [$11 million] of total indemnity), “errors in diagnosis” (25% of closed claims, 46% were paid; 44% [$17 million] of total indemnity), and “no medical misadventure” (14% of closed claims, 8% were paid; less than 1% [$148,000] of total indemnity). Another physician was named in 32% of claims, and consent issues/breach of contract were cited in 18%. Claims for injury resulting in death represented 39% of closed claims and 25% of total indemnity. “Improper performance” was the primary alleged error associated with injury resulting in death. Compared with claims involving death, major temporary injury (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.29-5.85, P=.009), significant permanent injury (OR 3.1, 95% CI 1.48-6.46, P=.003), and major permanent injury (OR 5.5, 95% CI 1.89-16.15, P=.002) had a higher likelihood of a claim resulting in indemnity payment. Conclusions: Improper performance was the most common alleged malpractice error. Claims involving significant or major injury were more likely to be paid than those involving death. Insights into the nature of liability claims against

  12. Nature of Medical Malpractice Claims Against Radiation Oncologists

    International Nuclear Information System (INIS)

    Marshall, Deborah; Tringale, Kathryn; Connor, Michael; Punglia, Rinaa; Recht, Abram; Hattangadi-Gluth, Jona

    2017-01-01

    Purpose: To examine characteristics of medical malpractice claims involving radiation oncologists closed during a 10-year period. Methods and Materials: Malpractice claims filed against radiation oncologists from 2003 to 2012 collected by a nationwide liability insurance trade association were analyzed. Outcomes included the nature of claims and indemnity payments, including associated presenting diagnoses, procedures, alleged medical errors, and injury severity. We compared the likelihood of a claim resulting in payment in relation to injury severity categories (death as referent) using binomial logistic regression. Results: There were 362 closed claims involving radiation oncology, 102 (28%) of which were paid, resulting in $38 million in indemnity payments. The most common alleged errors included “improper performance” (38% of closed claims, 18% were paid; 29% [$11 million] of total indemnity), “errors in diagnosis” (25% of closed claims, 46% were paid; 44% [$17 million] of total indemnity), and “no medical misadventure” (14% of closed claims, 8% were paid; less than 1% [$148,000] of total indemnity). Another physician was named in 32% of claims, and consent issues/breach of contract were cited in 18%. Claims for injury resulting in death represented 39% of closed claims and 25% of total indemnity. “Improper performance” was the primary alleged error associated with injury resulting in death. Compared with claims involving death, major temporary injury (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.29-5.85, P=.009), significant permanent injury (OR 3.1, 95% CI 1.48-6.46, P=.003), and major permanent injury (OR 5.5, 95% CI 1.89-16.15, P=.002) had a higher likelihood of a claim resulting in indemnity payment. Conclusions: Improper performance was the most common alleged malpractice error. Claims involving significant or major injury were more likely to be paid than those involving death. Insights into the nature of liability claims against

  13. World high background natural radiation areas: Need to protect public from radiation exposure

    International Nuclear Information System (INIS)

    Sohrabi, Mehdi

    2013-01-01

    Highlights of findings on radiological measurements, radiobiological and epidemiological studies in some main world high background natural radiation (HBNR) areas such as in Brazil, China, India and Iran are presented and discussed with special regard to remediation of radiation exposure of inhabitants in such areas. The current radiation protection philosophy and recommendations applied to workers and public from operation of radiation and nuclear applications are based on the linear non-threshold (LNT) model. The inhabitants of HBNR and radon prone areas receive relatively high radiation doses. Therefore, according to the LNT concept, the inhabitants in HBNR areas and in particular those in Ramsar are considered at risk and their exposure should be regulated. The HBNR areas in the world have different conditions in terms of dose and population. In particular, the inhabitants in HBNR areas of Ramsar receive very high internal and external exposures. This author believes that the public in such areas should be protected and proposes a plan to remedy high exposure of the inhabitants of the HBNR areas of Ramsar, while maintaining these areas as they stand to establish a national environmental radioactivity park which can be provisionally called “Ramsar Research Natural Radioactivity Park” (RRNRP). The major HBNR areas, the public exposure and the need to remedy exposures of inhabitants are reviewed and discussed. - Highlights: ► Highlights of findings on studies in HBNR areas are reviewed and discussed. ► The need to protect HBNR area inhabitants and remedy public exposure is emphasized. ► A collective approach is proposed to remedy exposure of Ramsar HBNR area inhabitants. ► Relocation of HBNR area inhabitants and establishing a park at the location is proposed. ► The advantages and disadvantages of the methods are discussed and recommendations are made

  14. Treatment of the radiation-contaminated plant wastes by bacteria (using the space agriculture)

    International Nuclear Information System (INIS)

    Yamashita, Masamichi

    2012-01-01

    The use of the hyperthermophilic aerobic-composting bacteria system in the space agriculture is proposed for the countermeasure of radiation-contaminated plants in the Fukushima radiation accident. (M.H.)

  15. Predictions of space radiation fatality risk for exploration missions.

    Science.gov (United States)

    Cucinotta, Francis A; To, Khiet; Cacao, Eliedonna

    2017-05-01

    In this paper we describe revisions to the NASA Space Cancer Risk (NSCR) model focusing on updates to probability distribution functions (PDF) representing the uncertainties in the radiation quality factor (QF) model parameters and the dose and dose-rate reduction effectiveness factor (DDREF). We integrate recent heavy ion data on liver, colorectal, intestinal, lung, and Harderian gland tumors with other data from fission neutron experiments into the model analysis. In an earlier work we introduced distinct QFs for leukemia and solid cancer risk predictions, and here we consider liver cancer risks separately because of the higher RBE's reported in mouse experiments compared to other tumors types, and distinct risk factors for liver cancer for astronauts compared to the U.S. The revised model is used to make predictions of fatal cancer and circulatory disease risks for 1-year deep space and International Space Station (ISS) missions, and a 940 day Mars mission. We analyzed the contribution of the various model parameter uncertainties to the overall uncertainty, which shows that the uncertainties in relative biological effectiveness (RBE) factors at high LET due to statistical uncertainties and differences across tissue types and mouse strains are the dominant uncertainty. NASA's exposure limits are approached or exceeded for each mission scenario considered. Two main conclusions are made: 1) Reducing the current estimate of about a 3-fold uncertainty to a 2-fold or lower uncertainty will require much more expansive animal carcinogenesis studies in order to reduce statistical uncertainties and understand tissue, sex and genetic variations. 2) Alternative model assumptions such as non-targeted effects, increased tumor lethality and decreased latency at high LET, and non-cancer mortality risks from circulatory diseases could significantly increase risk estimates to several times higher than the NASA limits. Copyright © 2017 The Committee on Space Research (COSPAR

  16. Performances of Kevlar and Polyethylene as radiation shielding on-board the International Space Station in high latitude radiation environment.

    Science.gov (United States)

    Narici, Livio; Casolino, Marco; Di Fino, Luca; Larosa, Marianna; Picozza, Piergiorgio; Rizzo, Alessandro; Zaconte, Veronica

    2017-05-10

    Passive radiation shielding is a mandatory element in the design of an integrated solution to mitigate the effects of radiation during long deep space voyages for human exploration. Understanding and exploiting the characteristics of materials suitable for radiation shielding in space flights is, therefore, of primary importance. We present here the results of the first space-test on Kevlar and Polyethylene radiation shielding capabilities including direct measurements of the background baseline (no shield). Measurements are performed on-board of the International Space Station (Columbus modulus) during the ALTEA-shield ESA sponsored program. For the first time the shielding capability of such materials has been tested in a radiation environment similar to the deep-space one, thanks to the feature of the ALTEA system, which allows to select only high latitude orbital tracts of the International Space Station. Polyethylene is widely used for radiation shielding in space and therefore it is an excellent benchmark material to be used in comparative investigations. In this work we show that Kevlar has radiation shielding performances comparable to the Polyethylene ones, reaching a dose rate reduction of 32 ± 2% and a dose equivalent rate reduction of 55 ± 4% (for a shield of 10 g/cm 2 ).

  17. Radiation Doses to Hanford Workers from Natural Potassium-40

    International Nuclear Information System (INIS)

    Strom, Daniel J.; Lynch, Timothy P.; Weier, Dennis R.

    2009-01-01

    The chemical element potassium is an essential mineral in people and is subject to homeostatic regulation. Natural potassium comprises three isotopes, 39K, 40K, and 41K. Potassium-40 is radioactive, with a half life of 1.248 billion years. In most transitions, it emits a ?- particle with a maximum energy of 0.560 MeV, and sometimes a gamma photon of 1.461 MeV. Because it is ubiquitous, 40K produces radiation dose to all human beings. This report contains the results of new measurements of 40K in 248 adult females and 2,037 adult males performed at the Department of Energy Hanford Site in 2006 and 2007. Potassium concentrations diminish with age, are generally lower in women than in men, and decrease with body mass index (BMI). The average annual effective dose from 40K in the body is 0.149 mSv y?1 for men and 0.123 mSv y?1 women respectively. Averaged over both men and women, the average effective dose per year is 0.136 mSv y?1. Calculated effective doses range from 0.069 to 0.243 mSv y?1 for adult males, and 0.067 to 0.203 mSv y?1 for adult females, a roughly three-fold variation for each gender. The need for dosimetric phantoms with a greater variety of BMI values should be investigated. From our data, it cannot be determined whether the potassium concentration in muscle in people with large BMI values differs from that in people with small BMI values. Similarly, it would be important to know the potassium concentration in other soft tissues, since much of the radiation dose is due to beta radiation, in which the source and target tissues are the same. These uncertainties should be evaluated to determine their consequences for dosimetry

  18. Development of a multifunctional particle spectrometer for space radiation imaging

    International Nuclear Information System (INIS)

    Maddox, Erik; Palacios, Alex; Lampridis, Dimitris; Kraft, Stefan; Owens, Alan; Tomuta, Dana; Ostendorf, Reint

    2008-01-01

    For future exploration of the solar system, the European Space Agency (ESA) is planning missions to Mercury (BepiColombo), the Sun (SolarOrbiter) and to the moons of Jupiter and Saturn. The expected intensity of radiation during such missions is hazardous for the scientific instruments and the satellite. To extend the lifetime of the satellite and its payload a multifunctional particle spectrometer (MPS) is being developed. The basic function of the MPS is to send an alarm signal to the satellite control system during periods of high radiation. In addition the MPS is a scientific instrument that will unfold the composition of the different contributing particles on-line by the dE/dx versus E method. The energy spectrum and angular distribution of the particles will be recorded as well. This article describes the main requirements and the base line design for the MPS. A readout scheme consisting of a 32 channel ASIC from IDEAS is proposed and the signal filtering algorithm will run on a digital signal processor based on FPGA technology. Results are shown from prototype calibration studies with a proton beam

  19. CERN@school: a new app displays natural radiation data

    CERN Multimedia

    Julio Rosenfeld

    2012-01-01

    A student from the Simon Langton Grammar School for Boys in Kent (UK) has developed an app that displays data recorded by Medipix chips. Created for Android-based devices, the app is a new way for students to visualize the natural radiation in their local area.   James Hurst shows off the Medipix chips at his school's stand at the UK's Royal Society Summer Science Exhibition. James Hurst, 17, developed the app in the framework of the CERN@school project that Becky Parker, a former participant in CERN’s High School Teachers (HST) programme, set up in 2008. “The app is able to display pre-recorded data in both graphic and numeric formats,” explains James. “I am already envisaging further developments, which might include producing the iOS version and eventually a live data-taking system.” CLEAR (Comprehensive Langton Evaluation and Analysis of Radiation), as it is named, will soon be available free from the Android Market toget...

  20. Effect of Gamma radiation on microbial population of natural casings

    International Nuclear Information System (INIS)

    Trigo, M.J.; Fraqueza, M.J.

    1998-01-01

    The high microbial load of fresh and dry natural casings increases the risk of meat product contamination with pathogenic microorganims, agents of foodborn diseases. The aim of this work is to evaluate the killing effect of gamma radiation on the resident microbial population of pork and beef casings, to improve their hygiene and safety. Portions of fresh pork (small intestine and colon) and dry beef casings were irradiated in a Cobalt 60 source with absorbed doses of 1, 2, 5 and 10 kGy. The D 10 values of total aerobic microorganisms in the pork casings were 1.65 kGy for colon and 1.54 kGy for small intestine. The D 10 value found in beef dry casings (small intestine) was 10.17 kGy. Radurization with 5 kGy was able to reduce, at least, 6 logs the coliform bacteria in pork casings. The killing effect over faecal Streptococci was 4 logs for pork fresh casings and 2 logs for beef dry casings. Gamma radiation with 5 kGy proved to be a convenient method to reduce substantially the microbial population of pork fresh casings. Otherwise, the microbial population of beef dry casings still resisted to 10 kGy

  1. Thermal annealing of natural, radiation-damaged pyrochlore

    Energy Technology Data Exchange (ETDEWEB)

    Zietlow, Peter; Mihailova, Boriana [Hamburg Univ. (Germany). Dept. of Earth Sciences; Beirau, Tobias [Hamburg Univ. (Germany). Dept. of Earth Sciences; Stanford Univ., CA (United States). Dept. of Geological Sciences; and others

    2017-03-01

    Radiation damage in minerals is caused by the α-decay of incorporated radionuclides, such as U and Th and their decay products. The effect of thermal annealing (400-1000 K) on radiation-damaged pyrochlores has been investigated by Raman scattering, X-ray powder diffraction (XRD), and combined differential scanning calorimetry/thermogravimetry (DSC/TG). The analysis of three natural radiation-damaged pyrochlore samples from Miass/Russia [6.4 wt% Th, 23.1.10{sup 18} α-decay events per gram (dpg)], Panda Hill/Tanzania (1.6 wt% Th, 1.6.10{sup 18} dpg), and Blue River/Canada (10.5 wt% U, 115.4.10{sup 18} dpg), are compared with a crystalline reference pyrochlore from Schelingen (Germany). The type of structural recovery depends on the initial degree of radiation damage (Panda Hill 28%, Blue River 85% and Miass 100% according to XRD), as the recrystallization temperature increases with increasing degree of amorphization. Raman spectra indicate reordering on the local scale during annealing-induced recrystallization. As Raman modes around 800 cm{sup -1} are sensitive to radiation damage (M. T. Vandenborre, E. Husson, Comparison of the force field in various pyrochlore families. I. The A{sub 2}B{sub 2}O{sub 7} oxides. J. Solid State Chem. 1983, 50, 362, S. Moll, G. Sattonnay, L. Thome, J. Jagielski, C. Decorse, P. Simon, I. Monnet, W. J. Weber, Irradiation damage in Gd{sub 2}Ti{sub 2}O{sub 7} single crystals: Ballistic versus ionization processes. Phys. Rev. 2011, 84, 64115.), the degree of local order was deduced from the ratio of the integrated intensities of the sum of the Raman bands between 605 and 680 cm{sup -1} divided by the sum of the integrated intensities of the bands between 810 and 860 cm{sup -1}. The most radiation damaged pyrochlore (Miass) shows an abrupt recovery of both, its short- (Raman) and long-range order (X-ray) between 800 and 850 K, while the weakly damaged pyrochlore (Panda Hill) begins to recover at considerably lower temperatures (near 500 K

  2. IEEE Nuclear and Space Radiation Effects Conference: Notes on the Early Conferences

    Science.gov (United States)

    Pellish, Jonathan A.; Galloway, Kenneth F.

    2013-01-01

    This paper gathers the remembrances of several key contributors who participated in the earliest Institute of Electrical and Electronics Engineers (IEEE) Nuclear and Space Radiation Effects Conferences (NSREC).

  3. GERMcode: A Stochastic Model for Space Radiation Risk Assessment

    Science.gov (United States)

    Kim, Myung-Hee Y.; Ponomarev, Artem L.; Cucinotta, Francis A.

    2012-01-01

    A new computer model, the GCR Event-based Risk Model code (GERMcode), was developed to describe biophysical events from high-energy protons and high charge and energy (HZE) particles that have been studied at the NASA Space Radiation Laboratory (NSRL) for the purpose of simulating space radiation biological effects. In the GERMcode, the biophysical description of the passage of HZE particles in tissue and shielding materials is made with a stochastic approach that includes both particle track structure and nuclear interactions. The GERMcode accounts for the major nuclear interaction processes of importance for describing heavy ion beams, including nuclear fragmentation, elastic scattering, and knockout-cascade processes by using the quantum multiple scattering fragmentation (QMSFRG) model. The QMSFRG model has been shown to be in excellent agreement with available experimental data for nuclear fragmentation cross sections. For NSRL applications, the GERMcode evaluates a set of biophysical properties, such as the Poisson distribution of particles or delta-ray hits for a given cellular area and particle dose, the radial dose on tissue, and the frequency distribution of energy deposition in a DNA volume. By utilizing the ProE/Fishbowl ray-tracing analysis, the GERMcode will be used as a bi-directional radiation transport model for future spacecraft shielding analysis in support of Mars mission risk assessments. Recent radiobiological experiments suggest the need for new approaches to risk assessment that include time-dependent biological events due to the signaling times for activation and relaxation of biological processes in cells and tissue. Thus, the tracking of the temporal and spatial distribution of events in tissue is a major goal of the GERMcode in support of the simulation of biological processes important in GCR risk assessments. In order to validate our approach, basic radiobiological responses such as cell survival curves, mutation, chromosomal

  4. Personalized Cancer Risk Assessments for Space Radiation Exposures

    Directory of Open Access Journals (Sweden)

    Michael M. Weil

    2016-02-01

    Full Text Available Individuals differ in their susceptibility to radiogenic cancers and there is evidence that this inter-individual susceptibility extends to HZE ion-induced carcinogenesis. Three components of individual risk: sex, age at exposure and prior tobacco use, are already incorporated into the NASA cancer risk model used to determine safe days in space for US astronauts. Here we examine other risk factors that could potentially be included in risk calculations. These include personal and family medical history, the presence of pre-malignant cells that could undergo malignant transformation as a consequence of radiation exposure, the results from phenotypic assays of radiosensitivity, heritable genetic polymorphisms associated with radiosensitivity, and post-flight monitoring. Inclusion of these additional risk or risk reduction factors has the potential to personalize risk estimates for individual astronauts and could influence the determination of safe days in space. We consider how this type of assessment could be used and explore how the provisions of the federal Genetic Information Nondiscrimination Act could impact the collection, dissemination and use of this information by NASA.

  5. Radiation Modification of Some Natural Polymers and Their Potential Applications

    International Nuclear Information System (INIS)

    Refaee, A.M.E.A.

    2012-01-01

    In recent years, antioxidants received remarkable attention due to the ability to preserve foodstuffs by retarding deterioration, rancidity and/or discoloration caused by oxidation of fats and oils in foods. In addition, they have the ability to protect against detrimental change of oxidizable nutrients and extend shelf life of foods. Nowadays, polysaccharides have been demonstrated to scavenge free radicals in vitro and to be used as antioxidants for the prevention of oxidative damage in foods. The antioxidant activity of polysaccharides depends upon several structural parameters, such as the molecular weight, amount, type and position of functional groups. For these applications, specific molecular weights are required. Thus, modification and preparation of low molecular weight fractions or oligosaccharides from chitosan, Na-alginate and carrageenan using ionizing radiation will be carried out and their antioxidant properties will be determined. The molecular weights and structure changes upon the radiation degradation process of these natural polymers in solid and solution form will be investigated using GPC, FT-IR, UV-Vis spectrophotometers. In an attempt to improve the functionality and water solubility of chitosan, chemical modifications will be done to introduce hydrophilic groups and enhance its antioxidant activity. Radical mediated lipid peroxidation inhibition, scavenging effect on DPPH radicals, reducing power and the ferrous ion chelating activity assays will be used to evaluate the antioxidant activity of oligosaccharides. Effectiveness of irradiated chitosan derivatives in reducing the lipid peroxidation in minced chicken will be investigated for improving the oxidative deterioration of minced chicken during refrigerated storage. On the other hand, there is a strong need for new plant growth media with increased water and nutrient holding capacity. Hydrogels have the ability to absorb large quantities of water. Among of these hydrogels polyacrylamide

  6. Radiation Hardened Nanobridge based Non-volatile Memory for Space Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This NASA Phase I SBIR program would develop and demonstrate radiation hardened nanobridge based non-volatile memory (NVM) for space applications. Specifically, we...

  7. Lightweight, Damage-Tolerant Radiator for In-Space Power and Propulsion

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear-electric propulsion promises numerous advantages over other in-space propulsion technologies. However, one serious limitation is the mass of the radiator...

  8. Predictions of space radiation fatality risk for exploration missions

    Science.gov (United States)

    Cucinotta, Francis A.; To, Khiet; Cacao, Eliedonna

    2017-05-01

    In this paper we describe revisions to the NASA Space Cancer Risk (NSCR) model focusing on updates to probability distribution functions (PDF) representing the uncertainties in the radiation quality factor (QF) model parameters and the dose and dose-rate reduction effectiveness factor (DDREF). We integrate recent heavy ion data on liver, colorectal, intestinal, lung, and Harderian gland tumors with other data from fission neutron experiments into the model analysis. In an earlier work we introduced distinct QFs for leukemia and solid cancer risk predictions, and here we consider liver cancer risks separately because of the higher RBE's reported in mouse experiments compared to other tumors types, and distinct risk factors for liver cancer for astronauts compared to the U.S. population. The revised model is used to make predictions of fatal cancer and circulatory disease risks for 1-year deep space and International Space Station (ISS) missions, and a 940 day Mars mission. We analyzed the contribution of the various model parameter uncertainties to the overall uncertainty, which shows that the uncertainties in relative biological effectiveness (RBE) factors at high LET due to statistical uncertainties and differences across tissue types and mouse strains are the dominant uncertainty. NASA's exposure limits are approached or exceeded for each mission scenario considered. Two main conclusions are made: 1) Reducing the current estimate of about a 3-fold uncertainty to a 2-fold or lower uncertainty will require much more expansive animal carcinogenesis studies in order to reduce statistical uncertainties and understand tissue, sex and genetic variations. 2) Alternative model assumptions such as non-targeted effects, increased tumor lethality and decreased latency at high LET, and non-cancer mortality risks from circulatory diseases could significantly increase risk estimates to several times higher than the NASA limits.

  9. 1987 Annual Conference on Nuclear and Space Radiation Effects, Snowmass Village, CO, July 28-31, 1987, Proceedings

    Science.gov (United States)

    1987-01-01

    Various papers on nuclear and space radiation effects are presented. The general topics addressed include: basic mechanisms of radiation effects, single-event phenomena, temperature and field effects, modeling and characterization of radiation effects, IC radiation effects and hardening, and EMP/SGEMP/IEMP phenomena. Also considered are: dosimetry/energy-dependent effects, sensors in and for radiation environments, spacecraft charging and space radiation effects, radiation effects and devices, radiation effects on isolation technologies, and hardness assurance and testing techniques.

  10. Particle Radiation Sources, Propagation and Interactions in Deep Space, at Earth, the Moon, Mars, and Beyond: Examples of Radiation Interactions and Effects

    Science.gov (United States)

    Schwadron, Nathan A.; Cooper, John F.; Desai, Mihir; Downs, Cooper; Gorby, Matt; Jordan, Andrew P.; Joyce, Colin J.; Kozarev, Kamen; Linker, Jon A.; Mikíc, Zoran; Riley, Pete; Spence, Harlan E.; Török, Tibor; Townsend, Lawrence W.; Wilson, Jody K.; Zeitlin, Cary

    2017-11-01

    Particle radiation has significant effects for astronauts, satellites and planetary bodies throughout the Solar System. Acute space radiation hazards pose risks to human and robotic exploration. This radiation also naturally weathers the exposed surface regolith of the Moon, the two moons of Mars, and other airless bodies, and contributes to chemical evolution of planetary atmospheres at Earth, Mars, Venus, Titan, and Pluto. We provide a select review of recent areas of research covering the origin of SEPs from coronal mass ejections low in the corona, propagation of events through the solar system during the anomalously weak solar cycle 24 and important examples of radiation interactions for Earth, other planets and airless bodies such as the Moon.

  11. Coupled radiative gasdynamic interaction and non-equilibrium dissociation for large-scale returned space vehicles

    International Nuclear Information System (INIS)

    Surzhikov, S.

    2012-01-01

    Graphical abstract: It has been shown that different coupled vibrational dissociation models, being applied for solving coupled radiative gasdynamic problems for large size space vehicles, exert noticeable effect on radiative heating of its surface at orbital entry on high altitudes (h ⩾ 70 km). This influence decreases with decreasing the space vehicles sizes. Figure shows translational (solid lines) and vibrational (dashed lines) temperatures in shock layer with (circle markers) and without (triangles markers) radiative-gasdynamic interaction for one trajectory point of entering space vehicle. Highlights: ► Nonequilibrium dissociation processes exert effect on radiation heating of space vehicles (SV). ► The radiation gas dynamic interaction enhances this influence. ► This influence increases with increasing the SV sizes. - Abstract: Radiative aerothermodynamics of large-scale space vehicles is considered for Earth orbital entry at zero angle of attack. Brief description of used radiative gasdynamic model of physically and chemically nonequilibrium, viscous, heat conductive and radiative gas of complex chemical composition is presented. Radiation gasdynamic (RadGD) interaction in high temperature shock layer is studied by means of numerical experiment. It is shown that radiation–gasdynamic coupling for orbital space vehicles of large size is important for high altitude part of entering trajectory. It is demonstrated that the use of different models of coupled vibrational dissociation (CVD) in conditions of RadGD interaction gives rise temperature variation in shock layer and, as a result, leads to significant variation of radiative heating of space vehicle.

  12. Managing the natural disasters from space technology inputs

    Science.gov (United States)

    Jayaraman, V.; Chandrasekhar, M. G.; Rao, U. R.

    1997-01-01

    Natural disasters, whether of meteorological origin such as Cyclones, Floods, Tornadoes and Droughts or of having geological nature such as earthquakes and volcanoes, are well known for their devastating impacts on human life, economy and environment. With tropical climate and unstable land forms, coupled with high population density, poverty, illiteracy and lack of infrastructure development, developing countries are more vulnerable to suffer from the damaging potential of such disasters. Though it is almost impossible to completely neutralise the damage due to these disasters, it is, however possible to (i) minimise the potential risks by developing disaster early warning strategies (ii) prepare developmental plans to provide resilience to such disasters, (iii) mobilize resources including communication and telemedicinal services and (iv) to help in rehabilitation and post-disaster reconstruction. Space borne platforms have demonstrated their capability in efficient disaster management. While communication satellites help in disaster warning, relief mobilisation and telemedicinal support, Earth observation satellites provide the basic support in pre-disaster preparedness programmes, in-disaster response and monitoring activities, and post-disaster reconstruction. The paper examines the information requirements for disaster risk management, assess developing country capabilities for building the necessary decision support systems, and evaluate the role of satellite remote sensing. It describes several examples of initiatives from developing countries in their attempt to evolve a suitable strategy for disaster preparedness and operational framework for the disaster management Using remote sensing data in conjunction with other collateral information. It concludes with suggestions and recommendations to establish a worldwide network of necessary space and ground segments towards strengthening the technological capabilities for disaster management and mitigation.

  13. Meeting the Grand Challenge of Protecting Astronaut's Health: Electrostatic Active Space Radiation Shielding for Deep Space Missions

    Data.gov (United States)

    National Aeronautics and Space Administration — This study will seek to test and validate an electrostatic gossamer structure to provide radiation shielding. It will provide guidelines for energy requirements,...

  14. Anti-radiation vaccine: Immunologically-based Prophylaxis of Acute Toxic Radiation Syndromes Associated with Long-term Space Flight

    Science.gov (United States)

    Popov, Dmitri; Maliev, Vecheslav; Jones, Jeffrey; Casey, Rachael C.

    2007-01-01

    Protecting crew from ionizing radiation is a key life sciences problem for long-duration space missions. The three major sources/types of radiation are found in space: galactic cosmic rays, trapped Van Allen belt radiation, and solar particle events. All present varying degrees of hazard to crews; however, exposure to high doses of any of these types of radiation ultimately induce both acute and long-term biological effects. High doses of space radiation can lead to the development of toxicity associated with the acute radiation syndrome (ARS) which could have significant mission impact, and even render the crew incapable of performing flight duties. The creation of efficient radiation protection technologies is considered an important target in space radiobiology, immunology, biochemistry and pharmacology. Two major mechanisms of cellular, organelle, and molecular destruction as a result of radiation exposure have been identified: 1) damage induced directly by incident radiation on the macromolecules they encounter and 2) radiolysis of water and generation of secondary free radicals and reactive oxygen species (ROS), which induce chemical bond breakage, molecular substitutions, and damage to biological molecules and membranes. Free-radical scavengers and antioxidants, which neutralize the damaging activities of ROS, are effective in reducing the impact of small to moderate doses of radiation. In the case of high doses of radiation, antioxidants alone may be inadequate as a radioprotective therapy. However, it remains a valuable component of a more holistic strategy of prophylaxis and therapy. High doses of radiation directly damage biological molecules and modify chemical bond, resulting in the main pathological processes that drive the development of acute radiation syndromes (ARS). Which of two types of radiation-induced cellular lethality that ultimately develops, apoptosis or necrosis, depends on the spectrum of incident radiation, dose, dose rate, and

  15. Space and energy: relationships among architects from nature

    Directory of Open Access Journals (Sweden)

    Silvia Titotto

    2015-07-01

    Full Text Available This research reflects on the possibility of architecture eco-sustainable development from the point of view of energy, space and environmental heritage, based on the constructive process of some species of social wasps (Hymenoptera and termites (Isoptera. It aimed at understanding via computational modelling and physical prototipation how their spacial design is developed by the “architect-insects” while they build their nests in nature as a way of preserving their bio-cultural heritage besides exploring other possibilites of eco-sustainable technological innovation within low energy consumption. The present work has been made to complement and converge the researches made both in the biomimicry area and the energy field by presenting how one can adapt the solutions in the built space of wasp nests and termite mounds that can be used in many ways at human constructions. Departing from some remarkable work done by entomologists, biologists and engineers, it was possible to get to structural details and how these tiny creatures build their dwellings little by little while they work as a united civilization. After getting to these details, strenghts and weaknesses were reported and one searched similar architectural human solutions for topics such as the crafting work on the surface of the buildings, the ventilation system created by the termites and the improvement of living spaces. By following the life of these little creatures and seeing how they can behave similarly to a human society up to an extent, one notes that one might learn and find architectural solutions by better understanding wasps and termites form-function challenges.

  16. Fifth international symposium on the natural radiation environment (NRE - V). Book of abstracts

    International Nuclear Information System (INIS)

    1991-01-01

    Most of the 219 contributions Are on radon (to a much lesser extent: thoron) and its daughter products in dwellings and in the environment; on corresponding measuring instruments and - methods; on measurements done; and on radiation doses to professional workers and to the public. The section heading give a fairly good account of the subject matters treated. Measurement Techniques and Metrology (Nrs 1-33); Exposure to Natural Radiation in Non-Domestic Environments (34-56); Natural Radionuclides and Transfer Pathways (57-107); Radioactivity and Radiation in the Human Environment (108-183); Health Effects of Natural Radiation (184-205); Industrially Modified Levels of Radiation Exposure (206-219). (Quittner)

  17. Comparative proteomic analysis of rice after seed ground simulated radiation and spaceflight explains the radiation effects of space environment

    Science.gov (United States)

    Wang, Wei; Shi, Jinming; Liang, Shujian; Lei, Huang; Shenyi, Zhang; Sun, Yeqing

    In previous work, we compared the proteomic profiles of rice plants growing after seed space-flights with ground controls by two-dimensional difference gel electrophoresis (2-D DIGE) and found that the protein expression profiles were changed after seed space environment exposures. Spaceflight represents a complex environmental condition in which several interacting factors such as cosmic radiation, microgravity and space magnetic fields are involved. Rice seed is in the process of dormant of plant development, showing high resistance against stresses, so the highly ionizing radiation (HZE) in space is considered as main factor causing biological effects to seeds. To further investigate the radiation effects of space environment, we performed on-ground simulated HZE particle radiation and compared between the proteomes of seed irra-diated plants and seed spaceflight (20th recoverable satellite) plants from the same rice variety. Space ionization shows low-dose but high energy particle effects, for searching the particle effects, ground radiations with the same low-dose (2mGy) but different liner energy transfer (LET) values (13.3KeV/µm-C, 30KeV/µm-C, 31KeV/µm-Ne, 62.2KeV/µm-C, 500Kev/µm-Fe) were performed; using 2-D DIGE coupled with clustering and principle component analysis (PCA) for data process and comparison, we found that the holistic protein expression patterns of plants irradiated by LET-62.2KeV/µm carbon particles were most similar to spaceflight. In addition, although space environment presents a low-dose radiation (0.177 mGy/day on the satellite), the equivalent simulated radiation dose effects should still be evaluated: radiations of LET-62.2KeV/µm carbon particles with different cumulative doses (2mGy, 20mGy, 200mGy, 2000mGy) were further carried out and resulted that the 2mGy radiation still shared most similar proteomic profiles with spaceflight, confirming the low-dose effects of space radiation. Therefore, in the protein expression level

  18. Natural and man-made environmental background radiation exposure levels: a review

    International Nuclear Information System (INIS)

    Puranik, V.D.; Ramachandran, T.V.

    2005-01-01

    All living organisms are continuously exposed to ionizing radiation, which always existed naturally. Important sources are cosmic rays which comes from outer space and from the surface of the sun, terrestrial radionuclides which occurs in the earth's crust, in building materials and in air, water and foods and in the human body itself. Some of the exposures are fairly constant and uniform for all individuals everywhere, for example, the dose from ingestion of potassium-40 in food. Other exposures vary depending on location. Cosmic rays, for example are, more intense at higher altitudes, and the concentrations of uranium and thorium in soils are elevated in localized areas. Exposures can also vary as a result of human activities and practices. In particular, the building materials of houses and the design and ventilation systems strongly influences the indoor levels of the radioactive gas radon and its decay products, which contributes significantly to doses through inhalation. Component of the sources of exposures to Indian population has been assessed based on the data generated. Total estimated contribution to the natural sources to the Indian population works out to 2.3 mSv/y as against the global value of 2.4 mSv/y. Estimated modified source which includes mining of heavy metals, coal fired power plants, mining of phosphate rocks and its use as fertilizers, production of natural gas, production of gas mantles and luminescent dial and air travel contribution to the background radiation to the Indian population works out to be 1.2 x 10 -3 mSv/y; while atmospheric weapon tests contributes about 0.045 mSv/y, medical exposure contributes about 0.048 mSv/y and exposure due to nuclear power production contributes about 5.0 x 10 -5 mSv/y to the background radiation. Brief review and comparison of the dose rates arising from natural and other man made sources to the Indian population is given. (author)

  19. What Reliability Engineers Should Know about Space Radiation Effects

    Science.gov (United States)

    DiBari, Rebecca

    2013-01-01

    Space radiation in space systems present unique failure modes and considerations for reliability engineers. Radiation effects is not a one size fits all field. Threat conditions that must be addressed for a given mission depend on the mission orbital profile, the technologies of parts used in critical functions and on application considerations, such as supply voltages, temperature, duty cycle, and redundancy. In general, the threats that must be addressed are of two types-the cumulative degradation mechanisms of total ionizing dose (TID) and displacement damage (DD). and the prompt responses of components to ionizing particles (protons and heavy ions) falling under the heading of single-event effects. Generally degradation mechanisms behave like wear-out mechanisms on any active components in a system: Total Ionizing Dose (TID) and Displacement Damage: (1) TID affects all active devices over time. Devices can fail either because of parametric shifts that prevent the device from fulfilling its application or due to device failures where the device stops functioning altogether. Since this failure mode varies from part to part and lot to lot, lot qualification testing with sufficient statistics is vital. Displacement damage failures are caused by the displacement of semiconductor atoms from their lattice positions. As with TID, failures can be either parametric or catastrophic, although parametric degradation is more common for displacement damage. Lot testing is critical not just to assure proper device fi.mctionality throughout the mission. It can also suggest remediation strategies when a device fails. This paper will look at these effects on a variety of devices in a variety of applications. This paper will look at these effects on a variety of devices in a variety of applications. (2) On the NEAR mission a functional failure was traced to a PIN diode failure caused by TID induced high leakage currents. NEAR was able to recover from the failure by reversing the

  20. The effect of space radiation of the nervous system

    Science.gov (United States)

    Gauger, Grant E.; Tobias, Cornelius A.; Yang, Tracy; Whitney, Monroe

    The long-term effects of irradiation by accelerated heavy ions on the structure and function of the nervous system have not been studied extensively. Although the adult brain is relatively resistant to low LET radiation, cellular studies indicate that individual heavy ions can produce serious membrane lesions and multiple chromatin breaks. Capillary hemorrhages may follow high LET particle irradiation of the developing brain as high RBE effects. Evidence has been accumulating that the glial system and blood-brain barrier (BBB) are relatively sensitive to injury by ionizing radiation. While DNA repair is active in neural systems, it may be assumed that a significant portion of this molecular process is misrepair. Since the expression of cell lethality usually requires cell division, and nerve cells have an extremely low rate of division, it is possible that some of the characteristic changes of premature aging may represent a delayed effect of chromatin misrepair in brain. Altered microcirculation, decreased local metabolism, entanglement and reduction in synaptic density, premature loss of neurons, myelin degeneration, and glial proliferation are late signs of such injuries. HZE particles are very efficient in producing carcinogenic cell transformation, reaching a peak for iron particles. The promotion of viral transformation is also efficient up to an energy transfer of approximately 300 keV/micron. The RBE for carcinogenesis in nerve tissues remains unknown. On the basis of available information concerning HZE particle flux in interplanetary space, only general estimates of the magnitude of the effects of long-term spaceflight on some nervous system parameters may be constructed.

  1. Radiation Doses to Hanford Workers from Natural Potassium-40

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Daniel J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lynch, Timothy P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weier, Dennis R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2009-02-01

    The chemical element potassium is an essential mineral in people and is subject to homeostatic regulation. Natural potassium comprises three isotopes, 39K, 40K, and 41K. Potassium-40 is radioactive, with a half life of 1.248 billion years. In most transitions, it emits a β particle with a maximum energy of 0.560 MeV, and sometimes a gamma photon of 1.461 MeV. Because it is ubiquitous, 40K produces radiation dose to all human beings. This report contains the results of new measurements of 40K in 248 adult females and 2,037 adult males performed at the Department of Energy Hanford Site in 2006 and 2007. Potassium concentrations diminish with age, are generally lower in women than in men, and decrease with body mass index (BMI). The average annual effective dose from 40K in the body is 0.149 mSv y-1 for men and 0.123 mSv y-1 women respectively. Averaged over both men and women, the average effective dose per year is 0.136 mSv y-1. Calculated effective doses range from 0.069 to 0.243 mSv y-1 for adult males, and 0.067 to 0.203 mSv y-1 for adult females, a roughly three-fold variation for each gender. The need for dosimetric phantoms with a greater variety of BMI values should be investigated. From our data, it cannot be determined whether the potassium concentration in muscle in people with large BMI values differs from that in people with small BMI values. Similarly, it would be important to know the potassium concentration in other soft tissues, since much of the radiation dose is due to beta radiation, in which the source and target tissues are the same. These uncertainties should be evaluated to determine their consequences for dosimetry.

  2. Space charge dosimeters for extremely low power measurements of radiation in shipping containers

    Science.gov (United States)

    Britton, Jr; Charles, L [Alcoa, TN; Buckner, Mark A [Oak Ridge, TN; Hanson, Gregory R [Clinton, TN; Bryan, William L [Knoxville, TN

    2011-04-26

    Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes in situ polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

  3. The Discrete Nature of the Coherent Synchrotron Radiation

    Science.gov (United States)

    Tammaro, Stefano; Pirali, Olivier; Roy, P.; Lampin, Jean François; Ducourneau, Gaël; Cuisset, Arnaud; Hindle, Francis; Mouret, Gaël

    2015-06-01

    Frequency Combs (FC) have radically changed the landscape of frequency metrology and high-resolution spectroscopy investigations extending tremendously the achievable resolution while increasing signal to noise ratio. Initially developed in the visible and near-IR spectral regions, the use of FC has been expanded to mid-IR, extreme ultra-violet and X-ray. Significant effort is presently dedicated to the generation of FC at THz frequencies. One solution based on converting a stabilized optical frequency comb using a photoconductive terahertz emitter, remains hampered by the low available THz power. Another approach is based on active mode locked THz quantum-cascade-lasers providing intense FC over a relatively limited spectral extension. Alternatively, we show that dense powerful THz FC is generated over one decade of frequency by coherent synchrotron radiation (CSR). In this mode, the entire ring behaves in a similar fashion to a THz resonator wherein electron bunches emit powerful THz pulses quasi-synchronously. The observed FC has been fully characterized and is demonstrated to be offset free. Based on these recorded specifications and a complete review of existing THz frequency comb, a special attention will be paid onto similarities and differences between them. Udem, Th., Holzwarth, H., Hänsch, T. W., Optical frequency metrology. Nature 416, 233-237 (2002) Schliesser, A., Picqué, N., Hänsch, T. W., Mid-infrared frequency combs. Nature Photon. 6, 440 (2012) Zinkstok, R. Th., Witte, S., Ubachs, W., Hogervorst, W., Eikema, K. S. E., Frequency comb laser spectroscopy in the vacuum-ultraviolet region. Physical Review A 73, 061801 (2006) Cavaletto, S. M. et al. Broadband high-resolution X-ray frequency combs. Nature Photon. 8, 520-523 (2014) Tani, M., Matsuura, S., Sakai, K., Nakashima, S. I., Emission characteristics of photoconductive antennas based on low-temperature-grown GaAs and semi-insulating GaAs. Applied Optics 36, 7853-7859 (1997) Burghoff, D. et al

  4. Natural and anthropogenic radiation exposure of humans in Germany; Natuerliche und zivilisatorische Strahlenexposition des Menschen in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Koelzer, Winfried

    2016-12-15

    The contribution on natural and anthropogenic radiation exposure in Germany covers the following issues: (1) natural radiation exposure: external radiation exposure - cosmic and terrestric radiation, internal radiation exposure - primordial and cosmogenic radionuclides; radiation exposure due to sola neutrinos and geo-neutrinos. (2) Anthropogenic radiation exposure: radiation exposure in medicine, radioactivity in industrial products, radiation exposure during flights, radiation exposure due to nuclear facilities, radiation exposure due to fossil energy carriers in power generation, radiation exposure due to nuclear explosions, radiation exposure due to nuclear accidents. (3) Occupational radiation exposure in Germany: radiation monitoring with personal dosimeters in medicine and industry, dose surveillance of the aviation personal, working places with increases radiation exposure by natural radiation sources.

  5. [The model of radiation shielding of the service module of the International space station].

    Science.gov (United States)

    Kolomenskiĭ, A V; Kuznetsov, V G; Laĭko, Iu A; Bengin, V V; Shurshakov, V A

    2001-01-01

    Compared and contrasted were models of radiation shielding of habitable compartments of the basal Mir module that had been used to calculate crew absorbed doses from space radiation. Developed was a model of the ISS Service module radiation shielding. It was stated that there is a good agreement between experimental shielding function and the one calculated from this model.

  6. Issues in space radiation shielding for lunar base

    International Nuclear Information System (INIS)

    Oishi, Koji

    1995-01-01

    Precise estimation of production of secondary neutrons from space radiation particles in the thick shield is very important to define dose rate inside the lunar base. NASA has developed one-dimensional baryon transport code BRYNTRN, which requires only a very small fraction of computer resources. However, for neutrons, backward production and scattering are not modeled in BRYNTRN. Comparisons of the calculated secondary particle spectra in lunar concrete and regolith at the depth of 10, 50, 100, and 200 g/cm 2 between BRYNTRN and Monte-Carlo calculation code system HETC-MCNP were performed. From the comparison, large underestimation of the calculated result of BRYNTRN in the lower neutron energy region, En<10 MeV, were observed. Verification of nuclear data used in MCNP calculation for low energy neutrons were performed, and good agreement between experiment and calculation was obtained. It is concluded that careful consideration for the lower energy neutrons will be required by using BRYNTRN transport code system. (author)

  7. Calibration and application of medical particle accelerators to space radiation experiments

    International Nuclear Information System (INIS)

    Ryu, Kwangsun; Park, Miyoung; Chae, Jangsoo; Yoon, Sangpil; Shin, Dongho

    2012-01-01

    In this paper, we introduce radioisotope facilities and medical particle accelerators that can be applied to space radiation experiments and the experimental conditions required by the space radiation experiments. Space radiation experiments on the ground are critical in determining the lifetimes of satellites and in choosing or preparing the appropriate electrical parts to assure the designated mission lifetime. Before the completion of building the 100-MeV proton linear accelerator in Gyeongju, or even after the completion, the currently existing proton accelerators for medical purposes could suggest an alternative plan. We have performed experiments to calibrate medical proton beam accelerators to investigate whether the beam conditions are suitable for applications to space radiation experiments. Based on the calibration results, we propose reference beam operation conditions for space radiation experiments.

  8. Ionizing Radiation Environment on the International Space Station: Performance vs. Expectations for Avionics and Material

    Science.gov (United States)

    Koontz, Steven L.; Boeder, Paul A.; Pankop, Courtney; Reddell, Brandon

    2005-01-01

    The role of structural shielding mass in the design, verification, and in-flight performance of International Space Station (ISS), in both the natural and induced orbital ionizing radiation (IR) environments, is reported. Detailed consideration of the effects of both the natural and induced ionizing radiation environment during ISS design, development, and flight operations has produced a safe, efficient manned space platform that is largely immune to deleterious effects of the LEO ionizing radiation environment. The assumption of a small shielding mass for purposes of design and verification has been shown to be a valid worst-case approximation approach to design for reliability, though predicted dependences of single event effect (SEE) effects on latitude, longitude, SEP events, and spacecraft structural shielding mass are not observed. The Figure of Merit (FOM) method over predicts the rate for median shielding masses of about 10g/cm(exp 2) by only a factor of 3, while the Scott Effective Flux Approach (SEFA) method overestimated by about one order of magnitude as expected. The Integral Rectangular Parallelepiped (IRPP), SEFA, and FOM methods for estimating on-orbit (Single Event Upsets) SEU rates all utilize some version of the CREME-96 treatment of energetic particle interaction with structural shielding, which has been shown to underestimate the production of secondary particles in heavily shielded manned spacecraft. The need for more work directed to development of a practical understanding of secondary particle production in massive structural shielding for SEE design and verification is indicated. In contrast, total dose estimates using CAD based shielding mass distributions functions and the Shieldose Code provided a reasonable accurate estimate of accumulated dose in Grays internal to the ISS pressurized elements, albeit as a result of using worst-on-worst case assumptions (500 km altitude x 2) that compensate for ignoring both GCR and secondary particle

  9. A phase-space beam position monitor for synchrotron radiation

    International Nuclear Information System (INIS)

    Samadi, Nazanin; Bassey, Bassey; Martinson, Mercedes; Belev, George; Dallin, Les; Jong, Mark de; Chapman, Dean

    2015-01-01

    A system has been developed to measure the vertical position and angle of the electron beam at a single location from a synchrotron source. The system uses a monochromator tuned to the absorption edge of a contrast material and has a sensitivity comparable with other beam position monitors. The stability of the photon beam position on synchrotron beamlines is critical for most if not all synchrotron radiation experiments. The position of the beam at the experiment or optical element location is set by the position and angle of the electron beam source as it traverses the magnetic field of the bend-magnet or insertion device. Thus an ideal photon beam monitor would be able to simultaneously measure the photon beam’s position and angle, and thus infer the electron beam’s position in phase space. X-ray diffraction is commonly used to prepare monochromatic beams on X-ray beamlines usually in the form of a double-crystal monochromator. Diffraction couples the photon wavelength or energy to the incident angle on the lattice planes within the crystal. The beam from such a monochromator will contain a spread of energies due to the vertical divergence of the photon beam from the source. This range of energies can easily cover the absorption edge of a filter element such as iodine at 33.17 keV. A vertical profile measurement of the photon beam footprint with and without the filter can be used to determine the vertical centroid position and angle of the photon beam. In the measurements described here an imaging detector is used to measure these vertical profiles with an iodine filter that horizontally covers part of the monochromatic beam. The goal was to investigate the use of a combined monochromator, filter and detector as a phase-space beam position monitor. The system was tested for sensitivity to position and angle under a number of synchrotron operating conditions, such as normal operations and special operating modes where the photon beam is intentionally altered

  10. Natural radiation source fabricated from commercially available instant coffee

    International Nuclear Information System (INIS)

    Kawano, Takao; Ando, Yoshiaki; Izumi, Yuuichi

    2015-01-01

    Commercially available instant coffee, Nescafe Excella, contained the radionuclide 40 K. From the instant coffee, sixteen coffee-block radiation sources were successfully fabricated with sufficiently low production dependences. The coffee-block radiation sources were examined their suitability for a radiation protection course. Although a part of radiation counts(cpm) obtained with 1 minute measurement were largely deviated, those determined by 5 minute measurements and five times of 1 minute measurement were less deviated, enabling better comprehension of the three cardinal principles of radiation protection. (author)

  11. International Space Station Instmments Collect Imagery of Natural Disasters

    Science.gov (United States)

    Evans, C. A.; Stefanov, W. L.

    2013-01-01

    A new focus for utilization of the International Space Station (ISS) is conducting basic and applied research that directly benefits Earth's citizenry. In the Earth Sciences, one such activity is collecting remotely sensed imagery of disaster areas and making those data immediately available through the USGS Hazards Data Distribution System, especially in response to activations of the International Charter for Space and Major Disasters (known informally as the "International Disaster Charter", or IDC). The ISS, together with other NASA orbital sensor assets, responds to IDC activations following notification by the USGS. Most of the activations are due to natural hazard events, including large floods, impacts of tropical systems, major fires, and volcanic eruptions and earthquakes. Through the ISS Program Science Office, we coordinate with ISS instrument teams for image acquisition using several imaging systems. As of 1 August 2013, we have successfully contributed imagery data in support of 14 Disaster Charter Activations, including regions in both Haiti and the east coast of the US impacted by Hurricane Sandy; flooding events in Russia, Mozambique, India, Germany and western Africa; and forest fires in Algeria and Ecuador. ISS-based sensors contributing data include the Hyperspectral Imager for the Coastal Ocean (HICO), the ISERV (ISS SERVIR Environmental Research and Visualization System) Pathfinder camera mounted in the US Window Observational Research Facility (WORF), the ISS Agricultural Camera (ISSAC), formerly operating from the WORF, and high resolution handheld camera photography collected by crew members (Crew Earth Observations). When orbital parameters and operations support data collection, ISS-based imagery adds to the resources available to disaster response teams and contributes to the publicdomain record of these events for later analyses.

  12. International Space Station Instruments Collect Imagery of Natural Disasters

    Science.gov (United States)

    Evans, C. A.; Stefanov, W. L.

    2013-12-01

    A new focus for the International Space Station (ISS) is conducting basic and applied research that directly benefits Earth's citizenry. In the Earth Sciences, one such activity is collecting remotely sensed imagery of disaster areas and making those data immediately available through the USGS Hazards Data Distribution System, especially in response to activations of the International Charter for Space and Major Disasters (known informally as the 'International Disaster Charter', or IDC). The ISS, together with other NASA orbital sensor assets, responds to IDC activations following notification by the USGS. Most of the activations are due to natural hazard events, including large floods, impacts of tropical systems, major fires, and volcanic eruptions and earthquakes. Through the ISS Program Science Office, we coordinate with ISS instrument teams for image acquisition using several imaging systems. As of 1 August 2013, we have successfully contributed imagery data in support of 14 Disaster Charter Activations, including regions in both Haiti and the east coast of the US impacted by Hurricane Sandy; flooding events in Russia, Mozambique, India, Germany and western Africa; and forest fires in Algeria and Ecuador. ISS-based sensors contributing data include the Hyperspectral Imager for the Coastal Ocean (HICO), the ISERV (ISS SERVIR Environmental Research and Visualization System) Pathfinder camera mounted in the US Window Observational Research Facility (WORF), the ISS Agricultural Camera (ISSAC), formerly operating from the WORF, and high resolution handheld camera photography collected by crew members (Crew Earth Observations). When orbital parameters and operations support data collection, ISS-based imagery adds to the resources available to disaster response teams and contributes to the public-domain record of these events for later analyses.

  13. Technologically enhanced natural radiation (TENR II). Proceedings of an international symposium

    International Nuclear Information System (INIS)

    2002-02-01

    Natural radiation is ubiquitous. In recent decades, there has been a developing interest in fully documenting exposure of human beings to radiation of natural origin. Radiation experts have recognized that natural sources of radiation can cause exposure of members of the general public and workers to levels that warrant consideration of whether controls should be applied. The second International Symposium on Technologically Enhanced Natural Radiation (TENR II) was held in Rio de Janeiro from 12 to 17 September 1999. The objective of the symposium was to provide a forum for the international exchange of information on the scientific and technical aspects of those components of exposure to natural radiation that warrant consideration. These components were examined under the headings: the technological enhancement of natural radiation in mining and non-nuclear industries; radon indoors and outdoors; mobility and transfer of natural radionuclides; natural radiation and health effects; analytical techniques and methodologies; the remediation of contaminated sites; and regulatory and legal aspects. The symposium found that exposures to natural sources of radiation should be considered from the point of view of their amenability to control. This approach is reflected in the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) and the associated IAEA documents on occupational exposure and rehabilitation of contaminated lands. The concepts of exclusion and intervention are particularly relevant to the amenability to control of natural sources of radiation. Indeed, the BSS specify that any exposure whose magnitude is essentially unamenable to control through the requirements of the BSS is out of the scope of the BSS. The BSS further indicate that protective or remedial actions shall be undertaken whenever they are justified in terms of the benefit to be obtained. Following their deliberations, the

  14. Natural radiation - a perspective to radiological risk factors of nuclear energy production

    DEFF Research Database (Denmark)

    Mustonen, R.; Christensen, T.; Stranden, E.

    1992-01-01

    Radiation doses from natural radiation and from man-made modifications on natural radiation, and different natural radiological environments in the Nordic countries are summarized and used as a perspective for the radiological consequences of nuclear energy production. The significance of different...... radiation sources can be judged against the total collective effective dose equivalent from natural radiation in the Nordic countries, 92 000 manSv per year. The collective dose from nuclear energy production during normal operation is estimated to 20 manSv per year and from non-nuclear energy production...... of radionuclides from a final repository of spent nuclear fuel to the consequences of natural radionuclides in different environments. The danger index of natural radiological environments will not be significantly increased by future releases of nuclear fuel radionuclides....

  15. Optical power and energy radiated by natural lightning

    Science.gov (United States)

    Quick, Mason G.; Krider, E. Philip

    2013-02-01

    Calibrated measurements of the visible and near-infrared radiation produced by both negative and positive cloud-to-ground (CG) lightning strokes have been made at distances of 5 to 32 km in southern Arizona (AZ) and the central Great Plains using a photodiode sensor with a flat spectral response between 0.4 and 1.0 µm. Time-correlated video images (60 fps) of the channel development provided information about the types of strokes that were detected and reports from the U.S. National Lightning Detection Network indicated their locations, polarities, and estimates of their peak current. In our sample of negative strokes that were suitable for analysis, there were 23 first (or only) strokes (FS), 19 subsequent strokes that created new ground contacts (NGC), and 101 subsequent strokes that re-illuminated a preexisting channel (PEC). We also analyzed 10 positive strokes (in nine flashes), and 73 of the larger impulses that were radiated by intracloud discharges (CPs). Assuming that these events can be approximated as isotropic sources and that the effects of atmospheric extinction are negligible, the peak optical power (Po), total optical energy (Eo), and characteristic widths of the sources (tcw = Eo/Po) have been computed. Median values of Po for negative FS, NGC, and PEC strokes were 1.8 × 1010 W, 1.1 × 1010 W, and 4.4 × 109 W, respectively. Median values of Eo were 3.6 × 106 J, 3.5 × 106 J, and 1.2 × 106 J, respectively. The median characteristic widths of negative FS, NGC, and PEC strokes were 229 µs, 244 µs, and 283 µs, respectively. Positive CG strokes produced a median Po, Eo, and tcw of 1.9 × 1010 W, 9.3 × 106 J, and 497 µs, respectively. Estimates of the space-and-time-average power per unit length (ℓo) in the lower portion of negative FS, NGC, and PEC channels had medians of 2.8 × 106 W/m, 3.2 × 106 W/m, and 1.4 × 106 W/m, respectively, and the median ℓo for four positive strokes was 8.8 × 106 W/m. Median values for the estimated peak

  16. Natural radiation dose estimates from soils;Estimativas das doses de radiacao natural proveniente de solos

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, M.A.G.R.; Moreira, H. [Fundacao Educacional Inaciana Pe Saboia de Medeiros (FEI), Sao Jose dos Campos, SP (Brazil). Centro Universitario; Medina, N.H. [Universidade de Sao Paulo (IFUSP), SP (Brazil). Inst. de Fisica

    2009-07-01

    In this work the natural radiation from soils of southeastern Brazil has been studied. Soil samples from Interlagos, Sao Paulo; parks and Billings dam, in Sao Bernardo do Campo city; Santos, Sao Vicente and Sao Sebastiao beaches, Sao Paulo and sands from Ilha Grande beaches, Rio de Janeiro, were analyzed. The results show that the main contribution to the effective dose is due to elements of the {sup 232}Th decay chain, with a smaller contribution from the radionuclide {sup 40}K and the elements of the series of {sup 238}U. The obtained values found in the studied regions, are around the average international dose due to external exposure to gamma rays (0.48 mSv/yr), except in Praia Preta, Ilha Grande, where the effective dose exceeds the average value. (author)

  17. Embedding Nature of Science in Teaching About Astronomy and Space

    Science.gov (United States)

    Buaraphan, Khajornsak

    2012-06-01

    Science teachers need an adequate understanding of nature of science (NOS) and the ability to embed NOS in their teaching. This collective case study aims to explore in-service science teachers' conceptions of NOS and the embeddedness of NOS in their teaching about astronomy and space. Three science teachers participated in this study. All participants attended the NOS workshop based on an explicit-reflective approach. They were asked to respond to the Myths of Science Questionnaire on three different occasions, i.e., at the beginning and the end of the NOS workshop and a semester after the workshop. Classroom observation, interviews after teaching, and a collection of related documents were also employed to collect data. The data were analyzed using a constant comparative method. The results revealed two important assertions. First, science teachers' conceptions of NOS are stable and resistant to change. However, an explicit-reflective approach employed in the NOS workshop, to some extent, promoted science teachers' understanding and reasoning about NOS. Second, science teachers' conceptions of NOS are not directly related to their classroom practices. With different degrees of NOS understanding, all participants taught NOS implicitly and missed most of the opportunities to address aspects of NOS embedded in the topics they taught. The implications of these findings are also discussed.

  18. Characterizing the Radiation Survivability of Space Solar Cell Technologies for Heliospheric Missions

    Science.gov (United States)

    Lee, J. H.; Walker, D.; Mann, C. J.; Yue, Y.; Nocerino, J. C.; Smith, B. S.; Mulligan, T.

    2016-12-01

    Space solar cells are responsible for powering the majority of heliospheric space missions. This paper will discuss methods for characterizing space solar cell technologies for on-orbit operations that rely on a series of laboratory tests that include measuring the solar cells' beginning of life performance under simulated (e.g. AM0 or air mass zero) sunlight over different operating temperatures and observing their end of life performance following exposure to laboratory-generated charged particle radiation (protons and electrons). The Aerospace Corporation operates a proton implanter as well as electron gun facilities and collaborates with external radiation effects facilities to expose space solar cells or other space technologies to representative space radiation environments (i.e. heliosphere or magnetosphere of Earth or other planets), with goals of characterizing how the technologies perform over an anticipated space mission timeline and, through the application of precision diagnostic capabilities, understanding what part of the solar cell is impacted by varying space radiation environments. More recently, Aerospace has been hosting solar cell flight tests on its previously-flown CubeSat avionics bus, providing opportunities to compare the laboratory tests to on-orbit observations. We hope through discussion of the lessons learned and methods we use to characterize how solar cells perform after space radiation exposure that similar methodology could be adopted by others to improve the state of knowledge on the survivability of other space technologies required for future space missions.

  19. Multiple chromosome aberrations among newborns from high level natural radiation area and normal level natural radiation area of south west coast of Kerala

    International Nuclear Information System (INIS)

    Soren, D.C.; Ramachandran, E.N.; Karuppasamy, C.V.; Cheriyan, V.D.; Anil Kumar, V.; Koya, P.K.M.; Seshadri, M.

    2010-01-01

    Cord blood samples were collected in heparin vials and microculture techniques employed to obtain good metaphase chromosome spreads. In cytogenetic studies on newborns cells with multiple aberrations were recorded in 57 from a total of 27285 newborns (1266972 cells). Of these 17294 newborns (964140 cells) were from High Level Natural Radiation Area (HLNRA) and 9991 newborns (302832 cells) from Normal Level Natural Radiation Area (NLNRA). Cells with multiple aberrations were observed in 38 and 19 newborns from High and Normal Level Natural Radiation Area respectively. On an average one cell with multiple aberrations was observed among 479 newborns. Cells with multiple aberrations were observed in newborns from HLNRA as well as NLNRA in both males and females. Gender difference of newborns, maternal age group and background radiation levels did not seem to have any influence in the occurrence of Multiple chromosome aberrations

  20. Mapping the exposure of the Brazilian population to natural background radiation - cosmic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Rochedo, Elaine R.R., E-mail: elaine@ird.gov.br [Instituto de Radioprotecao e Dosimetria (lRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Salles, Krause C.S.; Prado, Nadya M.C., E-mail: krausesalles@yahoo.com.br, E-mail: nadya@ime.ib.br [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    The main objective of this work is to statically and graphically describe the exposure of the Brazilian population to natural background radiation. in this stage, doses due to cosmic rays is being assessed based on sea level dose rates, corrected by latitude and altitude, according to the model recommended by UNSCEAR. In this work, the doses were estimated for ali Brazilian municipalities with more than 100.000 inhabitants. The 253 municipalities selected for this study include about 52% of the Brazilian population. Average dose rate was estimated to be about 50 n Sv/h with a variation coefficient of 31%. The estimated doses have shown a strong influence of altitude on dose rates, with a correlation coefficient of 0,998 for ao exponential fit. This result confirms previous studies that show a large effect of the altitude 00 exposure from cosmic radiation. Considering the same occupation and shielding conditions used by UNSCEAR as global averages, average annual dose was estimated to be 0,37 (0,24 - 0,76) mSv/y, very close to UNSCEAR worldwide average of 0,38 (0,3 - 1,0) mSv/y. (author)

  1. Mapping the exposure of the Brazilian population to natural background radiation - cosmic radiation

    International Nuclear Information System (INIS)

    Rochedo, Elaine R.R.; Salles, Krause C.S.; Prado, Nadya M.C.

    2013-01-01

    The main objective of this work is to statically and graphically describe the exposure of the Brazilian population to natural background radiation. in this stage, doses due to cosmic rays is being assessed based on sea level dose rates, corrected by latitude and altitude, according to the model recommended by UNSCEAR. In this work, the doses were estimated for ali Brazilian municipalities with more than 100.000 inhabitants. The 253 municipalities selected for this study include about 52% of the Brazilian population. Average dose rate was estimated to be about 50 n Sv/h with a variation coefficient of 31%. The estimated doses have shown a strong influence of altitude on dose rates, with a correlation coefficient of 0,998 for ao exponential fit. This result confirms previous studies that show a large effect of the altitude 00 exposure from cosmic radiation. Considering the same occupation and shielding conditions used by UNSCEAR as global averages, average annual dose was estimated to be 0,37 (0,24 - 0,76) mSv/y, very close to UNSCEAR worldwide average of 0,38 (0,3 - 1,0) mSv/y. (author)

  2. The space experiment CERASP: Definition of a space-suited radiation source and growth conditions for human cells

    Science.gov (United States)

    Hellweg, Christine E.; Baumstark-Khan, Christa; Spitta, Luis; Thelen, Melanie; Arenz, Andrea; Franz, Markus; Schulze-Varnholt, Dirk; Berger, Thomas; Reitz, Günther

    The combined action of ionizing radiation and microgravity will continue to influence future space missions, with special risks for astronauts on the Moon surface or for long duration missions to Mars. It has been estimated that on a 3-year mission to Mars about 3% of the bodies' cell nuclei would have been hit by one iron ion with the consequence that nuclear DNA will be heavily damaged. There is increasing evidence that basic cellular functions are sensitive not only to radiation but also to microgravity. DNA repair studies in space on bacteria, yeast cells and human fibroblasts, which were irradiated before, flight, gave contradictory results: from inhibition of repair by microgravity to enhancement, whereas others did not detect any influence of microgravity on repair. The space experiment CERASP (CEllular Responses to RAdiation in SPace) to be performed at the International Space Station (ISS) is aimed to supply basic information on the cellular response in microgravity to radiation applied during flight. It makes use of a recombinant human cell line as reporter for cellular signal transduction modulation by genotoxic environmental conditions. The main biological endpoints under investigation will be gene activation based on enhanced green fluorescent protein (EGFP, originally isolated from the bioluminescent jellyfish Aequorea victoria) expression controlled by a DNA damage-dependent promoter element which reflects the activity of the nuclear factor kappa B (NF- κB) pathway. The NF- κB family of proteins plays a major role in the inflammatory and immune response, cell proliferation and differentiation, anti-apoptosis and tumorgenesis. For radiation exposure during space flight a radiation source has been constructed as damage accumulation by cosmic radiation will certainly be insufficient for analysis. The space experiment specific hardware consists of a specially designed radiation source made up of the β-emitter promethium-147, combined with a

  3. Estimation of natural radiation background level and population dose in China

    International Nuclear Information System (INIS)

    Pan Ziqiang

    1992-01-01

    The authors describe in general the natural radiation background level in China, and based on available data present an estimated annual effective dose equivalent of the population to natural radiation that is some 2.3 mSv, of which about 0.54 mSv is from original γ radiation and about 0.8 mSv from radon and its short-lived daughters

  4. Progress in R and D radiation processing of natural polymers in the Philippines

    International Nuclear Information System (INIS)

    Dela Rosa, A.; Abad, L.; Relleve, L.; Aranilla, C.; Cabalfin, E.; Bisnar, C.

    2007-01-01

    Radiation technology has emerged as an environment-friendly, commercially viable technology with broad applications that can essentially contribute to achieve the goal of sustainable development. Natural polymers are good raw materials since they are biodegradable, readily available in large quantity and at low cost. Radiation processing of natural polymers is a potential area to widen the prospect of industrial scale application of radiation technology in the Philippines. (author)

  5. Savings on natural gas consumption by doubling thermal efficiencies of balanced-flue space heaters

    Energy Technology Data Exchange (ETDEWEB)

    Juanico, Luis E. [Conicet, and Centro Atomico Bariloche e Instituto Balseiro, Av. Bustillo 9500, 8400 Bariloche, Rio Negro (Argentina); Gonzalez, Alejandro D. [Grupo de Estudios Ambientales, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (Inibioma-Conicet), 8400 Bariloche, Rio Negro (Argentina)

    2008-07-01

    Natural gas is a relatively clean fossil fuel for space heating. However, when it is not used efficiently high consumption can become an environmental problem. In Argentina, individual balanced-flue space heaters are the most extensively used in temperate and cold regions. This furnace is a simple device with a burner set into a metal chamber, separated from the indoor ambient by an enclosing cabinet, and both inlet and outgas chimneys are connected to the outdoor ambient. In previous studies, we measured the performance of these commercial devices, and found very low thermal efficiency (in the range of 39-63% depending on the chimney configuration). The extensive use of these devices is possible due to the availability of unlimited amount of subsidised natural gas to households and businesses. In the present work, we developed a prototype with simple and low cost modifications made on commercial models, and measured the improvements on the thermal efficiency. Findings showed better infrared radiation, enhanced indoor air convection, and passive chimney flow regulation leading to thermal efficiency in the range of 75-85%. These values represent an improvement of 100% when compared to marketed models, and hence, the specific cost of the heater per unit of useful heating power delivered was actually reduced. Considering the large market presence of these furnaces in both residential and business sectors in Argentina, the potential benefits related to gas consumption and environmental emissions are very significant. (author)

  6. Book of abstracts of the international conference on high levels of natural radiation held in Ramsar, Islamic Republic of Iran, 3-7 Nov 1990

    International Nuclear Information System (INIS)

    Sohrabi, M.; Borhan Azad, S.; Katouzi, M.

    1990-01-01

    Papers presented in international conference on high levels of natural radiation was in the following subjects: A review of world natural radiation, environmental transfer pathway,technologically enhanced natural radiation environment,radon in the environment,radium determination in water,cytogenetic studies in high natural radiation areas,epidemiological studies in high natural radiation areas and radiation measurements methods

  7. Is natural background or radiation from nuclear power plants leukemogenic?

    International Nuclear Information System (INIS)

    Cronkite, E.P.

    1989-01-01

    The objective in this review is to provide some facts about normal hemopoietic cell proliferation relevant to leukemogenesis, physical, chemical, and biological facts about radiation effects with the hope that each person will be able to decide for themselves whether background radiation or emissions from nuclear power plants and facilities significantly add to the spontaneous leukemia incidence. 23 refs., 1 tab

  8. Organization and operation of the Sixth International Symposium on the Natural Radiation Environment (NRE VI)

    International Nuclear Information System (INIS)

    Hopke, P.K.

    1996-01-01

    An important source of human exposure to radiation is the natural world including cosmic rays, cosmogenic radionuclides, natural terrestrial radionuclides, and radon isotopes and its decay products. Considerable effort is being expended on a worldwide basis to characterize the exposure to the natural radiation environment and determine the important pathways for the exposure to result in the dose to tissue that leads to injury and disease. The problem of background exposure to naturally occurring radioactivity has been the subject of research since the initial discovery of the radioactivity of uranium and thorium. However, with the advent of artificial sources of radiation with both benefits and harm the nature and magnitude of the natural radiation environment and the effects on various populations are important in the development of overall public health strategies as ALARA principles are applied to the situation

  9. Radiation Exposure and Mortality from Cardiovascular Disease and Cancer in Early NASA Astronauts: Space for Exploration

    Science.gov (United States)

    Elgart, S. R.; Little, M. P.; Campbell, L. J.; Milder, C. M.; Shavers, M. R.; Huff, J. L.; Patel, Z. S.

    2018-01-01

    Of the many possible health challenges posed during extended exploratory missions to space, the effects of space radiation on cardiovascular disease and cancer are of particular concern. There are unique challenges to estimating those radiation risks; care and appropriate and rigorous methodology should be applied when considering small cohorts such as the NASA astronaut population. The objective of this work was to establish whether there is evidence for excess cardiovascular disease or cancer mortality in an early NASA astronaut cohort and determine if a correlation exists between space radiation exposure and mortality.

  10. RESULTS OF THE NASA SPACE RADIATION LABORATORY BEAM STUDIES PROGRAM AT BNL.

    Energy Technology Data Exchange (ETDEWEB)

    BROWN,K.A.AHRENS,L.BEUTTENMULLER,R.H.ET AL.

    2004-07-05

    The NASA Space Radiation Laboratory (NSRL) was constructed in collaboration with NASA for the purpose of performing radiation effect studies for the NASA space program. The NSRL makes use of heavy ions in the range of 0.05 to 3 GeV/n slow extracted from BNL's AGS Booster. The purpose of the NSRL Beam Studies Program is to develop a clear understanding of the beams delivered to the facility, to fully characterize those beams, and to develop new capabilities in the interest of understanding the radiation environment in space. In this report we will describe the first results from this program.

  11. Radiation doses at high altitudes and during space flights

    Czech Academy of Sciences Publication Activity Database

    Spurný, František

    2001-01-01

    Roč. 61, 3-6 (2001), s. 301-307 ISSN 0969-806X Grant - others:EC project(XX) FIGM-CT2000-00068 Keywords : cosmic radiation * air crew * radiation protection Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 0.819, year: 2001

  12. RADIATION ENVIRONMENT AT AVIATION ALTITUDES AND IN SPACE

    Czech Academy of Sciences Publication Activity Database

    Sihver, L.; Ploc, Ondřej; Puchalska, M.; Ambrožová, Iva; Kubančák, Ján; Kyselová, Dagmar; Shurshakov, V.

    2015-01-01

    Roč. 164, č. 4 (2015), s. 477-483 ISSN 0144-8420 Institutional support: RVO:61389005 Keywords : cosmic radiation * radiation field * on-board spacecraft Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.894, year: 2015

  13. Radiation Hard Space Wire Gigabit Ethernet Compatible Transponder, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Current and future programs of near-Earth and deep space exploration performed by NASA and Department of Defense require the development of reconfigurable,...

  14. Squares of the natural numbers in radiation protection

    International Nuclear Information System (INIS)

    Parker, H.M.

    1977-01-01

    An informal history of radiation protection is given. The following topics are included: the discovery of x rays and their effects, the formation of the International Committee on X-ray and Radium Protection, the Manhattan Project and its plutonium aspects, dose limits and their origin, the increase in antinuclear writings, the publication of reports on radiation levels and effects, the role of the EPA in medical radiation, and the Oklo phenomenon. Recommendations for NCRP and ICRP actions are given. The publication also contains brief biographies of Lauriston S. Taylor and Herbert M. Parker

  15. Monitoring of increased natural occuring radiation exposure; Arbeitsplatzueberwachung bei erhoehter natuerlicher Strahlenexposition

    Energy Technology Data Exchange (ETDEWEB)

    Guhr, Andreas [ALTRAC Radon-Messtechnik, Berlin (Germany); Leissring, Nick [Bergtechnisches Ingenieurbuero GEOPRAX, Chemnitz (Germany)

    2015-07-01

    The radiation exposure due to natural occurring sources is a special challenge for the health and safety protection at workplaces. The monitoring of the radon exposure of employees in mines, radon-spa and in water works is regulated by prescription of radiation protection. The relevant compounds of the radiation exposure are the inhalation of radon and radon daughter products; terrestrial irradiation; ingestion of radioactive contaminated materials and the inhalation of contaminated dust. The monitoring of the radiation workers is realized essentially by measurements by radiation safety officer of the performing company, by an external engineering firm as well as by control measurements of experts of local authorities. The experiences in the practice have shown that in the field of operational radiation protection only a combination of personal- and operational dosimetry is suitable to avoid health hazards by work in fields with increased natural occurring radiation exposures.

  16. Studies on the multistage nature of radiation carcinogenesis

    International Nuclear Information System (INIS)

    Fry, R.J.M.; Ley, R.D.; Grube, D.; Staffeldt, E.

    1980-01-01

    With low dose levels of ionizing or ultraviolet radiation, the number of initiation events exceeds the number of tumors that grow to a detectable size. Ionizing radiation, which is a complete carcinogen, appears to be a more effective initiator than an enhancer or promoter. However, the initiation and promotion aspects of ionizing radiation have been studied in very few organ systems. In the case of UVR, with or without photosensitizers such as psoralens, the requirement of a relatively large number of exposures for carcinogenesis suggests that the expression of the initiated cells as frank tumors requires a number of events spread out over the time of the development of the tumor. Both ionizing and ultraviolet radiation are, perhaps, underutilized as tools for probing the mechanism of both initiation and promotion

  17. Are biological effects of space radiation really altered under the microgravity environment?

    Science.gov (United States)

    Yatagai, Fumio; Ishioka, Noriaki

    2014-10-01

    Two major factors of space environment are space radiation and microgravity. It is generally considered that a high level of ionizing radiation (IR) in space has an influence on living organisms including humans; therefore, the possible alteration of space-radiation influences by the microgravity environment is of great concern. In fact, examination of such a possibility has been extensively conducted since the early days of space experiments, suggesting a possible synergistic effect of radiation and microgravity in some experiments but a negative observation in others. Because these complicated results remain not well understood, we propose a solution to this problem. Gene expression analysis is one of the solutions to the problem. In fact, gene expression may be changed by microgravity, and further modification may be possible through IR. This result could reveal an interactive effect of both factors on the cellular responses, which could in turn reveal whether the human-health abnormalities expected under the microgravity environment can be altered by space radiation. We believe that this is a new aspect in the study of the interactive effect of radiation and microgravity. However, further improvements in space experimental technologies are required for future studies.

  18. NASA GeneLab Project: Bridging Space Radiation Omics with Ground Studies.

    Science.gov (United States)

    Beheshti, Afshin; Miller, Jack; Kidane, Yared; Berrios, Daniel; Gebre, Samrawit G; Costes, Sylvain V

    2018-04-13

    Accurate assessment of risks of long-term space missions is critical for human space exploration. It is essential to have a detailed understanding of the biological effects on humans living and working in deep space. Ionizing radiation from galactic cosmic rays (GCR) is a major health risk factor for astronauts on extended missions outside the protective effects of the Earth's magnetic field. Currently, there are gaps in our knowledge of the health risks associated with chronic low-dose, low-dose-rate ionizing radiation, specifically ions associated with high (H) atomic number (Z) and energy (E). The NASA GeneLab project ( https://genelab.nasa.gov/ ) aims to provide a detailed library of omics datasets associated with biological samples exposed to HZE. The GeneLab Data System (GLDS) includes datasets from both spaceflight and ground-based studies, a majority of which involve exposure to ionizing radiation. In addition to detailed information on radiation exposure for ground-based studies, GeneLab is adding detailed, curated dosimetry information for spaceflight experiments. GeneLab is the first comprehensive omics database for space-related research from which an investigator can generate hypotheses to direct future experiments, utilizing both ground and space biological radiation data. The GLDS is continually expanding as omics-related data are generated by the space life sciences community. Here we provide a brief summary of the space radiation-related data available at GeneLab.

  19. Deterministic and stochastic methods of calculation of polarization characteristics of radiation in natural environment

    Science.gov (United States)

    Strelkov, S. A.; Sushkevich, T. A.; Maksakova, S. V.

    2017-11-01

    We are talking about russian achievements of the world level in the theory of radiation transfer, taking into account its polarization in natural media and the current scientific potential developing in Russia, which adequately provides the methodological basis for theoretically-calculated research of radiation processes and radiation fields in natural media using supercomputers and mass parallelism. A new version of the matrix transfer operator is proposed for solving problems of polarized radiation transfer in heterogeneous media by the method of influence functions, when deterministic and stochastic methods can be combined.

  20. High-Resolution and Analytical TEM Investigation of Space Radiation Processing Effects in Primitive Solar System Materials and Airless Planetary Surface Environments

    Science.gov (United States)

    Christoffersen, R.; Rahman, Z.; Keller, L. P.; Dukes, C.; Baragiola, R.

    2012-01-01

    Energetic ions present in the diverse plasma conditions in space play a significant role in the formation and modification of solid phases found in environments ranging from the interstellar medium (ISM) to the surfaces of airless bodies such as asteroids and the Moon. These effects are often referred to as space radiation processing, a term that encompasses changes induced in natural space-exposed materials that may be only structural, such as in radiation-induced amorphization, or may involve ion-induced nanoscale to microscale chemical changes, as occurs in preferential sputtering and ion-beam mixing. Ion sputtering in general may also be responsible for partial or complete erosion of space exposed materials, in some instances possibly bringing about the complete destruction of free-floating solid grains in the ISM or in circumstellar nebular dust clouds. We report here on two examples of the application of high-resolution and analytical transmission electron microscopy (TEM) to problems in space radiation processing. The first problem concerns the role of space radiation processing in controlling the overall fate of Fe sulfides as hosts for sulfur in the ISM. The second problem concerns the known, but as yet poorly quantified, role of space radiation processing in lunar space weathering.

  1. 13th Workshop on Radiation Monitoring for the International Space Station - Final Program

    International Nuclear Information System (INIS)

    2008-01-01

    The Workshop on Radiation Monitoring for the International Space Station (WRMISS) has been held annually since 1996. The major purpose of WRMISS is to provide a forum for discussion of technical issues concerning radiation dosimetry aboard the International Space Station. This includes discussion of new results, improved instrumentation, detector calibration, and radiation environment and transport models. The goal of WRMISS is to enhance international efforts to provide the best information on the space radiation environment in low-Earth orbit and on the exposure of astronauts and cosmonauts in order to optimize the radiation safety of the ISS crew. During the 13 th Annual WRMISS, held in the Institute of Nuclear Physics (Krakow, Poland) on 8-10 September 2008, participants presented 47 lectures

  2. Natural radioactive phon

    International Nuclear Information System (INIS)

    Birjukovs, V.; Birjukov, P.

    2004-01-01

    The natural radiating phon is determined by radioactive isotopes of elements which time of half-decay is commensurable in due course existence of the Earth, dispersing in rocks, ground, water and air, and also space radiation. (authors)

  3. Low-Power Large-Area Radiation Detector for Space Science Measurements

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this task is to develop a low-power, large-area detectors from SiC, taking advantage of very low thermal noise characteristics and high radiation...

  4. LGM2605 as a mitigator of space radiation-induced vascular damage, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — LignaMed, LLC is a drug development company with a fast track strategy to approval of LGM2605, an oral small molecule for use as a radiation mitigating agent that...

  5. Innovative, Lightweight Thoraeus RubberTM for MMOD and Space Radiation Shielding, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NanoSonic offers an innovative manufacturing process to yield ultra-lightweight radiation shielding nanocomposites by exploiting the concept of the Thoraeus filter...

  6. High Resolution, Radiation Tolerant Focal Plane Array for Lunar And Deep Space Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Aerius Photonics and its partners propose the development of a high resolution, radiation hardened 3-D FLASH Focal Plane Array (FPA), with performance expected to be...

  7. Multifunctional Carbon Nanotube/Polyethylene Complex Composites for Space Radiation Shielding, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Polyethylene (PE), due to its high hydrogen content relative to its weight, has been identified by NASA as a promising radiation shielding material against galactic...

  8. Awareness for natural radiation potential zones in Archean Terrain of Chhattisgarh State

    International Nuclear Information System (INIS)

    Diwan, H.D.; Pande, S.K.

    2015-01-01

    In the environment, the natural radiations emitted by rocks and soils containing radioactive minerals, largely affected the human being in various aspects. The Chhattisgarh region characterized by the mineral of natural radiations with their relative distribution found in Granitic rocks of Archean age. Adjacent to Cratonic margins, exposures of outer fringes became suitable sites for radiation spread. It constituting towards the emission of radiation by the intrinsic content of minerals present in the host rock i.e. the terrestrial sources of radiation. The Archean terrain covers the surrounding areas of oval cup shaped sedimentary basin and it lies in the S.O.I. toposheet no. 64 G. H.I.K.L. To locate the marked potential zone for natural radiation, the investigation nearby aquatic component of main river and tributaries of Mahanadi river system is important. The presence of Granitic/ Pegmatite rocks at the boundaries of shield areas became promising areas for radiation generating mineral components. Occurrence in the potential zones expressed as lense shaped deposits or strips in dimension of IX1/2 with few hundred long belt. Presence of weathering of Uraninite minerals content remain yellow orange coloured impressions on the surface. In urban areas the background radiation in form of ionic radiation by the residential dwelling units accredates radiations. It needs awareness for Natural Radiation of under zones (NRPZ) in the region. To ensure the effective awareness programme, the area under consideration of natural radiation should take care of socially sustainable activities and spatio-temporal spread to motivate and implement various safety provisions. The model experiments can be sued from R and D point of view, also to alert the people to provide 'Safety, health and welfare of society'. (author)

  9. Review of NASA approach to space radiation risk assessments for Mars exploration.

    Science.gov (United States)

    Cucinotta, Francis A

    2015-02-01

    Long duration space missions present unique radiation protection challenges due to the complexity of the space radiation environment, which includes high charge and energy particles and other highly ionizing radiation such as neutrons. Based on a recommendation by the National Council on Radiation Protection and Measurements, a 3% lifetime risk of exposure-induced death for cancer has been used as a basis for risk limitation by the National Aeronautics and Space Administration (NASA) for low-Earth orbit missions. NASA has developed a risk-based approach to radiation exposure limits that accounts for individual factors (age, gender, and smoking history) and assesses the uncertainties in risk estimates. New radiation quality factors with associated probability distribution functions to represent the quality factor's uncertainty have been developed based on track structure models and recent radiobiology data for high charge and energy particles. The current radiation dose limits are reviewed for spaceflight and the various qualitative and quantitative uncertainties that impact the risk of exposure-induced death estimates using the NASA Space Cancer Risk (NSCR) model. NSCR estimates of the number of "safe days" in deep space to be within exposure limits and risk estimates for a Mars exploration mission are described.

  10. Estimation of Radiation Limit from a Huygens' Box under Non-Free-Space Conditions

    DEFF Research Database (Denmark)

    Franek, Ondrej; Sørensen, Morten; Bonev, Ivan Bonev

    2013-01-01

    The recently studied Huygens' box method has difficulties when radiation of an electronic module is to be determined under non-free-space conditions, i.e. with an enclosure. We propose an estimate on radiation limit under such conditions based only on the Huygens' box data from free...

  11. A pilot investigation of natural radiation in Danish houses

    International Nuclear Information System (INIS)

    Soerensen, A.; Boetter-Jensen, L.; Majborn, B.; Nielsen, S.P.

    1985-04-01

    As a prelude to a nationwide survey a pilot study was carried out to establish techniques and procedures for the measurement of indoor radiation in Denmark. A passive cup dosemeter was designed containing CR39 track detectors and TLD's to measure radon and external radiation, respectively. The adequate performance of the dosemeter was verified in a radon intercalibration in 1984 carried out at the National Radiological Protection Board, UK. A total of 82 dwellings were selected covering most regions of the country. The dwellings were monitored in two three-month periods, one in winter and the other in summer. The average dose rate in air from external radiation was 0.09 μGy h -1 . In the winter the average radon concentrations were 88 Bq m -3 and 24 Bq m -3 for single-family houses and flats, respectively; and in the summer the corresponding values were 52 Bq m -3 and 19 Bq m -3 . (author)

  12. ESA SSA Space Radiation Expert Service Centre: the Importance of Community Feedback

    Science.gov (United States)

    Crosby, Norma; Dierckxsens, Mark; Kruglanski, Michel; De Donder, Erwin; Calders, Stijn; Messios, Neophytos; Glover, Alexi

    2017-04-01

    End-users in a wide range of sectors both in space and on the ground are affected by space weather. In the frame of its Space Situational Awareness (SSA) programme (http://swe.ssa.esa.int/) the European Space Agency (ESA) is establishing a Space Weather (SWE) Service Network to support end-users in three ways: mitigate the effects of space weather on their systems, reduce costs, and improve reliability. Almost 40 expert groups from institutes and organisations across Europe contribute to this Network organised in five Expert Service Centres (ESCs) - Solar Weather, Heliospheric Weather, Space Radiation, Ionospheric Weather, Geomagnetic Conditions. To understand the end-user needs, the ESCs are supported by the SSCC (SSA Space Weather Coordination Centre) that offers first line support to the end-users. Here we present the mission of the Space Radiation ESC (R-ESC) (http://swe.ssa.esa.int/space-radiation) and the space domain services it supports. Furthermore, we describe how the R-ESC project complements past and ongoing projects both on national level as well as international (e.g. EU projects), emphasizing the importance of inter-disciplinary communication between different communities ranging from scientists, engineers to end-users. Such collaboration is needed if basic science is to be used most efficiently for the development of products and tools that provide end-users with what they actually need. Additionally, feedback from the various communities (projects) is also essential when defining future projects.

  13. Estimation of effective dose to public from external exposure to natural background radiation in saudi arabia

    International Nuclear Information System (INIS)

    Khalid, A. A.

    2003-01-01

    The effective dose values in sixteen cities in Saudi Arabia due to external exposure to natural radiation were evaluated. These doses are based on natural background components including external exposure to terrestrial radiation and cosmic rays. The importance of evaluating the effective dose to the public due to external exposure to natural background radiation lies in its epidemiological and dosimetric importance and in forming a basis for the assessment of the level of radioactive contamination or pollution in the environment in the future. The exposure to terrestrial radiation was measured using thermoluminescent dosimeters (TLD). The exposure from cosmic radiation was determined using empirical correlation. The values evaluated for the total annual effective dose in all cities were within the world average values. The highest total annual effective dose measured in Al-Khamis city was 802 μSv/y, as compared to 305 μSv/y in Dammam city, which was considered the lowest value

  14. NASA GeneLab Project: Bridging Space Radiation Omics with Ground Studies

    Science.gov (United States)

    Beheshti, Afshin; Miller, Jack; Kidane, Yared H.; Berrios, Daniel; Gebre, Samrawit G.; Costes, Sylvain V.

    2018-01-01

    Accurate assessment of risk factors for long-term space missions is critical for human space exploration: therefore it is essential to have a detailed understanding of the biological effects on humans living and working in deep space. Ionizing radiation from Galactic Cosmic Rays (GCR) is one of the major risk factors factor that will impact health of astronauts on extended missions outside the protective effects of the Earth's magnetic field. Currently there are gaps in our knowledge of the health risks associated with chronic low dose, low dose rate ionizing radiation, specifically ions associated with high (H) atomic number (Z) and energy (E). The GeneLab project (genelab.nasa.gov) aims to provide a detailed library of Omics datasets associated with biological samples exposed to HZE. The GeneLab Data System (GLDS) currently includes datasets from both spaceflight and ground-based studies, a majority of which involve exposure to ionizing radiation. In addition to detailed information for ground-based studies, we are in the process of adding detailed, curated dosimetry information for spaceflight missions. GeneLab is the first comprehensive Omics database for space related research from which an investigator can generate hypotheses to direct future experiments utilizing both ground and space biological radiation data. In addition to previously acquired data, the GLDS is continually expanding as Omics related data are generated by the space life sciences community. Here we provide a brief summary of space radiation related data available at GeneLab.

  15. Natural Microbial UV Radiation Filters - Mycosporine-like Amino Acids

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Temina, M.; Tolstikov, A. G.; Dembitsky, V. M.

    2004-01-01

    Roč. 49, č. 4 (2004), s. 339-352 ISSN 0015-5632 Institutional research plan: CEZ:AV0Z5020903 Keywords : uv radiation * maas * ultraviolet-b Subject RIV: EE - Microbiology, Virology Impact factor: 1.034, year: 2004

  16. The natural horn as an efficient sound radiating system ...

    African Journals Online (AJOL)

    Results obtained showed that the locally made horn are efficient sound radiating systems and are therefore excellent for sound production in local musical renditions. These findings, in addition to the portability and low cost of the horns qualify them to be highly recommended for use in music making and for other purposes ...

  17. Limitations on space flight due to cosmic radiations.

    Science.gov (United States)

    CURTIS, H J

    1961-02-03

    These conclusions (10) may be summarized as follows: 1) Flight below the Van Allen belts seems reasonably safe without radiation shielding. 2) It is probably impractical to shield a rocket sufficiently to permit a man to remain in the inner Van Allen belt for more than about an hour, but it should be possible for him to go through it without serious harm. 3) Shielding for the outer Van Allen belt is possible but would have to be quite heavy if a stay of more than a few hours were contemplated. 4) The primary cosmic radiation is not intense enough to deliver a serious radiation dose, even for exposures of a few weeks, and the heavy cosmic ray primaries do not seem to present an unusual hazard.

  18. Proceedings. Protection of the natural environment. International symposium on ionising radiation

    International Nuclear Information System (INIS)

    Amiro, B.; Johansson, Gunnar; Larsson, Carl-Magnus; Luening, M.

    1996-01-01

    The symposium was organised jointly by the Swedish Radiation Protection Institute and the Atomic Energy Control Board of Canada. The programme was organised around six major topics: Biological effects of ionising radiation; Ecological effects of ionising radiation; Behaviour and transport of radionuclides in the natural environment; Criteria for environmental protection; Assessment methodology; and Social and economic aspects. All 86 contributions (excluding the opening addresses) have been separately indexed

  19. The Los Alamos.confEic Radiation Environment Assimilation Model (DREAM) for Space Weather Specification and Forecasting

    Science.gov (United States)

    Reeves, G.; Freidel, R.; Chen, Y.; Koller, J.; Henderson, M.

    The Dynamic Radiation Environment Assimilation Model (DREAM) was developed at Los Alamos.confEnal Laboratory to assess, quantify, and predict the hazards from the natural space environment and the anthropogenic environment produced by high altitude nuclear explosions (HANE). DREAM was initially developed as a basic research activity to understand and predict the dynamics of the Earth's Van Allen radiation belts. It uses Kalman filter techniques to assimilate data from space environment instruments with a physics-based model of the radiation belts. DREAM can assimilate data from a variety of types of instruments and data with various levels of resolution and fidelity by assigning appropriate uncertainties to the observations. Data from any spacecraft orbit can be assimilated but DREAM was designed to function with as few as two spacecraft inputs: one from geosynchronous orbit and one from GPS orbit. With those inputs, DREAM can be used to predict the environment at any satellite in any orbit whether space environment data are available in those orbits or not. Even with very limited data input and relatively simple physics models, DREAM specifies the space environment in the radiation belts to a high level of accuracy. DREAM has been extensively tested and evaluated as we transition from research to operations. We report here on one set of test results in which we predict the environment in a highly-elliptical polar orbit. We also discuss long-duration reanalysis for spacecraft design, using DREAM for real-time operations, and prospects for 1-week forecasts of the radiation belt environment.

  20. Measurement of the natural radiation of the Belgian territory

    International Nuclear Information System (INIS)

    Gillard, J.; Flemal, J.M.; Deworm, J.P.; Slegers, W.

    1989-01-01

    A measurement campaign of natural occuring radionuclides was set up on the Belgian territory in order to assess the doses received by the Belgian population. The results of the measurements are published together with a map of natural occuring radionuclides and exposure rates. (L.D.C.)

  1. Space-type radiation induces multimodal responses in the mouse gut microbiome and metabolome.

    Science.gov (United States)

    Casero, David; Gill, Kirandeep; Sridharan, Vijayalakshmi; Koturbash, Igor; Nelson, Gregory; Hauer-Jensen, Martin; Boerma, Marjan; Braun, Jonathan; Cheema, Amrita K

    2017-08-18

    Space travel is associated with continuous low dose rate exposure to high linear energy transfer (LET) radiation. Pathophysiological manifestations after low dose radiation exposure are strongly influenced by non-cytocidal radiation effects, including changes in the microbiome and host gene expression. Although the importance of the gut microbiome in the maintenance of human health is well established, little is known about the role of radiation in altering the microbiome during deep-space travel. Using a mouse model for exposure to high LET radiation, we observed substantial changes in the composition and functional potential of the gut microbiome. These were accompanied by changes in the abundance of multiple metabolites, which were related to the enzymatic activity of the predicted metagenome by means of metabolic network modeling. There was a complex dynamic in microbial and metabolic composition at different radiation doses, suggestive of transient, dose-dependent interactions between microbial ecology and signals from the host's cellular damage repair processes. The observed radiation-induced changes in microbiota diversity and composition were analyzed at the functional level. A constitutive change in activity was found for several pathways dominated by microbiome-specific enzymatic reactions like carbohydrate digestion and absorption and lipopolysaccharide biosynthesis, while the activity in other radiation-responsive pathways like phosphatidylinositol signaling could be linked to dose-dependent changes in the abundance of specific taxa. The implication of microbiome-mediated pathophysiology after low dose ionizing radiation may be an unappreciated biologic hazard of space travel and deserves experimental validation. This study provides a conceptual and analytical basis of further investigations to increase our understanding of the chronic effects of space radiation on human health, and points to potential new targets for intervention in adverse radiation

  2. IR Thermography of International Space Station Radiator Panels

    Science.gov (United States)

    Koshti, Ajay; Winfree, WIlliam; Morton, Richard; Howell, Patricia

    2010-01-01

    Several non-flight qualification test radiators were inspected using flash thermography. Flash thermography data analysis used raw and second derivative images to detect anomalies (Echotherm and Mosaic). Simple contrast evolutions were plotted for the detected anomalies to help in anomaly characterization. Many out-of-family indications were noted. Some out-of-family indications were classified as cold spot indications and are due to additional adhesive or adhesive layer behind the facesheet. Some out-of-family indications were classified as hot spot indications and are due to void, unbond or lack of adhesive behind the facesheet. The IR inspection helped in assessing expected manufacturing quality of the radiators.

  3. Space Station Radiator Test Hosted by NASA Lewis at Plum Brook Station

    Science.gov (United States)

    Speth, Randall C.

    1998-01-01

    In April of 1997, the NASA Lewis Research Center hosted the testing of the photovoltaic thermal radiator that is to be launched in 1999 as part of flight 4A of the International Space Station. The tests were conducted by Lockheed Martin Vought Systems of Dallas, who built the radiator. This radiator, and three more like it, will be used to cool the electronic system and power storage batteries for the space station's solar power system. Three of the four units will also be used early on to cool the service module.

  4. Comparative influence of dose rate and radiation nature, on lethality after big mammals irradiation

    International Nuclear Information System (INIS)

    Destombe, C.; Le Fleche, Ph.; Grasseau, A.; Reynal, A.

    1997-01-01

    For the same dose and the 30 days lethality as biological criterion, the dose rate influence is more important than the radiation nature on the results of an big mammals total body irradiation. (authors)

  5. Radiation effects. Engineering handbook (methods of improving the radiation tolerance of electronics in space vehicles). Final report

    International Nuclear Information System (INIS)

    Holmes-siedle, A.; Freeman, R.

    1978-04-01

    Space radiation effects in electronic subsystems are discussed. Useful data from a wide range of sources are presented and methods which have been newly developed to provide engineering solutions to the problem of degradation of devices in space are described. The new developments include a simple model for analyzing space-charge buildup in MOS devices, a ranking scheme for CMOS - LSI circuits and improved dose transmission curves and tradeoff curves for spacecraft life against shield weight. A complete analysis of a piece of spacecraft equipment is given. Recommendations for future progress in hardness engineering are made

  6. Combined effect of natural convection and non-gray gas radiation ...

    Indian Academy of Sciences (India)

    The present paper reports numerical results of combined effects of non-gray gas radiation and natural convection between two vertical plates with partial heating at walls. The plates are symmetrical and made of two equal zones alternately isotherm and insulated. The idea is to predict that thermal radiation will attenuate the ...

  7. Characteristic of the radiation field in low earth orbit and in deep space

    International Nuclear Information System (INIS)

    Reitz, Guenther

    2008-01-01

    The radiation exposure in space by cosmic radiation can be reduced through careful mission planning and constructive measures as example the provision of a radiation shelter, but it cannot be completely avoided. The reason for that are the extreme high energies of particles in this field and the herewith connected high penetration depth in matter. For missions outside the magnetosphere ionizing radiation is recognized as the key factor through its impact on crew health and performance. In absence of sporadic solar particle events the radiation exposure in Low Earth orbit (LEO) inside Spacecraft is determined by the galactic cosmic radiation (protons and heavier ions) and by the protons inside the South Atlantic Anomaly (SAA), an area where the radiation belt comes closer to the earth surface due to a displacement of the magnetic dipole axes from the Earth's center. In addition there is an albedo source of neutrons produced as interaction products of the primary galactic particles with the atoms of the earth atmosphere. Outside the spacecraft the dose is dominated by the electrons of the horns of the radiation belt located at about 60 latitude in Polar Regions. The radiation field has spatial and temporal variations in dependence of the Earth magnetic field and the solar cycle. The complexity of the radiation field inside a spacecraft is further increased through the interaction of the high energy components with the spacecraft shielding material and with the body of the astronauts. In interplanetary missions the radiation belt will be crossed in a couple of minutes and therefore its contribution to their radiation exposure is quite small, but subsequently the protection by the Earth magnetic field is lost, leaving only shielding measures as exposure reduction means. The report intends to describe the radiation field in space, the interaction of the particles with the magnetic field and shielding material and give some numbers on the radiation exposure in low earth

  8. A novel DC Magnetron sputtering facility for space research and synchrotron radiation optics

    DEFF Research Database (Denmark)

    Hussain, A.M.; Christensen, Finn Erland; Pareschi, G.

    1998-01-01

    A new DC magnetron sputtering facility has been build up at the Danish Space Research Institute (DSRI), specially designed to enable uniform coatings of large area curved optics, such as Wolter-I mirror optics used in space telescopes and curved optics used in synchrotron radiation facilities...

  9. Acute effects of exposure to space radiation on CNS function and cognitive performance

    Science.gov (United States)

    On exploratory class missions, such as a mission to Mars, astronauts will be exposed to types and doses of radiation (cosmic rays) that are not experienced in low earth orbit where the Space Shuttle and International Space Station operate. Exposure to cosmic rays produces changes in neuronal functi...

  10. Sex differences in operant responding and survivability following exposure to space radiation

    Science.gov (United States)

    On exploratory class missions, such as a mission to Mars, astronauts will be exposed to types and doses of radiation (galactic cosmic rays [GCR]) which are not experienced in low earth orbit where the space shuttle and International Space Station operate. Despite the fact that the crew on such a mi...

  11. Natural environmental radioactivity with particular regard to radon gas and cosmic radiation

    International Nuclear Information System (INIS)

    Lowder, W.M.

    1993-01-01

    A paper given at the previous workshop described the growth of our knowledge of the nature and sources of human exposure to naturally-occurring radiation and radionuclides, and summarized assessments of the individual components of this exposure. Here, some recent developments relevant to the earlier conclusions are described, and a closer look is taken at the increasingly important human exposure contribution of cosmic radiation, especially at aircraft altitudes. (author). 21 refs, 1 tab

  12. BIOREGENERATIVE LIFE SUPPORT SYSTEMS IN THE SPACE (BLSS: THE EFFECTS OF RADIATION ON PLANTS

    Directory of Open Access Journals (Sweden)

    Carmen Arena

    2012-06-01

    Full Text Available The growth of plants in Space is a fundamental issue for Space exploration. Plants play an important role in the Bioregenerative Life Support Systems (BLSS to sustain human permanence in extraterrestrial environments. Under this perspective, plants are basic elements for oxygen and fresh food production as well as air regeneration and psychological support to the crew. The potentiality of plant survival and reproduction in space is limited by the same factors that act on the earth (e.g. light, temperature and relative humidity and by additional factors such as altered gravity and ionizing radiation. This paper analyzes plant responses to space radiation which is recognized as a powerful mutagen for photosynthetic organisms thus being responsible for morpho-structural, physiological and genetic alterations. Until now, many studies have evidenced how the response to ionizing radiation is influenced by several factors associated both to plant characteristics (e.g. cultivar, species, developmental stage, tissue structure and/or radiation features (e.g. dose, quality and exposure time. The photosynthetic machinery is particularly sensitive to ionizing radiation. The severity of the damages induced by ionizing radiation on plant cell and tissues may depend on the capability of plants to adopt protection mechanisms and/or repair strategies. In this paper a selection of results from studies on the effect of ionizing radiations on plants at anatomical and eco-physiological level is reported and some aspects related to radioresistance are explored.

  13. Limitations in predicting the space radiation health risk for exploration astronauts.

    Science.gov (United States)

    Chancellor, Jeffery C; Blue, Rebecca S; Cengel, Keith A; Auñón-Chancellor, Serena M; Rubins, Kathleen H; Katzgraber, Helmut G; Kennedy, Ann R

    2018-01-01

    Despite years of research, understanding of the space radiation environment and the risk it poses to long-duration astronauts remains limited. There is a disparity between research results and observed empirical effects seen in human astronaut crews, likely due to the numerous factors that limit terrestrial simulation of the complex space environment and extrapolation of human clinical consequences from varied animal models. Given the intended future of human spaceflight, with efforts now to rapidly expand capabilities for human missions to the moon and Mars, there is a pressing need to improve upon the understanding of the space radiation risk, predict likely clinical outcomes of interplanetary radiation exposure, and develop appropriate and effective mitigation strategies for future missions. To achieve this goal, the space radiation and aerospace community must recognize the historical limitations of radiation research and how such limitations could be addressed in future research endeavors. We have sought to highlight the numerous factors that limit understanding of the risk of space radiation for human crews and to identify ways in which these limitations could be addressed for improved understanding and appropriate risk posture regarding future human spaceflight.

  14. The BIOMAT facility at FAIR: a new tool for ground-based research in space radiation biophysics

    Science.gov (United States)

    Durante, Marco

    The BIOMAT facility at FAIR: a new tool for ground-based research in space radiation biophysics M.Durante The FAIR accelerator complex at GSI (placeCityDarmstadt, country-regionGermany) will be a unique facility, where heavy ions with energies up to about 45 A GeV can be used for radiation biology experiments. The study of these very high charge and energy (HZE) particles is not only interesting for understanding the mechanisms of radiation action in living system, but also for radiation protection purposes. For space radiobiology, it is generally acknowledged that accelerator-based experiments are preferable to expensive and poorly reproducible flight tests, which are also presently unable to simulate the space radiation field beyond Earth's geomagnetic field. For these very reason, NASA has started the Space Radiation Health Program, building the 34 M NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory (NY), and funding several research groups for studying biological effects of heavy ions with mass up to 56 (iron) and energy up to metricconverterProductID1 A1 A GeV. FAIR offers a number of unique opportunities in this frame. First, the beamtime available at NSRL is not sufficient to accommodate many non-US research groups, while the research needs are becoming urgent: uncertainty should be reduced to ±50% and effective countermeasures (physical and medical) developed by 2025 if a mission to Mars has to be performed within the first half of the XXI century. FAIR can be used to test a higher energy range (1- metricconverterProductID35 A35 A GeV), which has a low flux in space but is particularly penetrating and consequently impossible to shield. Finally, the raster scanning system used at GSI offers unique opportunities for biological experiments requiring precise exposures of parts of tissue or animal targets. The group of Biophysics at GSI has along experience in the field of space radiation protection, which naturally stems from heavy

  15. Gamma radiation in space and in the atmosphere

    International Nuclear Information System (INIS)

    Rocchia, R.

    1966-01-01

    We have shown that the γ radiation existing in the atmosphere is caused mainly by the Bremsstrahlung of the electrons of the electromagnetic cascades (∼ 50 per cent of the measured radiation), by the 511 keV radiation produced by the annihilation of positrons created in cascades (8 per cent of the measured intensity) and by the Compton γ degradation of this line (30 per cent of the measured intensity). The rest, slightly over 10 per cent, must be attributed to secondary causes such as the nuclear de-excitation γ to the internal Bremsstrahlung of charged particles created in nuclear stars, and to charged particles crossing our detector, since the latter was not fitted with a device for rejecting these particles. Experiments carried out in rockets at Colomb-Bechar confirm these results and have made it possible to detect and measure a primary γ radiation having an intensity of ∼ 2 γ cm 2 s -1 above 100 keV. The primary spectrum obeys an approximate E -2 law. (author) [fr

  16. Space Electronics Operating at High Temperatures and Radiation Levels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective is to produce high efficiency DC/DC power modules in a small low profile package that can tolerate extreme environment conditions. The primary effort...

  17. Real Time Space Radiation Effects in Electronic Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — The effects that solar particle events can have on operational electronic systems is a significant concern for all missions, but especially for those beyond Low...

  18. A Medipix-Based Small Personal Space Radiation Dosimeter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR effort will take the first step in improving the existing Medipix dosimeter technology in terms of advancing the technique now used to couple the actual...

  19. Space Electronics Operating at High Temperatures and Radiation Levels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposal represents a radical revolution in Power Management & Distribution (PMAD) that addresses many of the challenges for NASA missions that will operate...

  20. Real Time Space Radiation Effects in Electronic Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The ability to predict the occurrence and magnitude of solar particle events (coronal mass ejections and solar flares) has been elusive so exposure of astronauts and...

  1. Limitation of population's irradiation by natural sources of ionizing radiation

    International Nuclear Information System (INIS)

    Krisyuk, Eh.M.

    1989-01-01

    Review of works devoted to evaluating the human irradiation doses at the expense of the main sources of ionizing radiation, is given. It is shown that the human irradiation doses at the expense of DDP can be reduced 10 times and more. However to realize such measures it is necessary to study the efficiency and determine the cost of various protective activities as well as to develop the criteria of their realization necessity

  2. Radiation tolerant passive and active optical fiber products for use in space environments

    Science.gov (United States)

    Hill, Mark; Hankey, Judith; Gray, Rebecca

    2017-11-01

    This paper reports the radiation performance results of several new product types designed for high radiation environments. The products tested include radiation hardened highly birefringent (HiBi) passive products for polarised applications and radiation tolerant active erbium doped fiber products for amplifiers. Radiation hardened, short beatlength HiBi fiber products have been developed for high accuracy polarisation maintaining (PM) gyros and sensors at both 1310nm and 1550nm operation in the space environment. The fibers have been tested up to 5kGy (500krad) - levels which could be expected in extreme, extra-terrestrial space environments. Results show a consistently low Radiation Induced Attenuation (RIA) of fibers are intended for use in multichannel amplifiers in optical intersatellite communications. The structure of the fibers have been designed to deliver an accelerated recovery of radiation damage through photo-annealing using only the residual energy already available in an amplifier using a 980nm pumping regime. These products have been tested up to 200Gy (20krad) - levels which can be expected in Earth orbit environments over a 20-30 mission lifetime. Results show up to 100% recovery under continuous use for dose rates of 0.11rad/hr. It has also been demonstrated through analysis of the optical spectral output that this effect reverses the gain tilt, or spectral narrowing, induced by radiation damage through the C and L band. These combined fiber characteristics allow performance stability of the amplifier over the lifetime of the space mission.

  3. Van Allen Probes Mission Space Academy: Educating middle school students about Earth's mysterious radiation belts

    Science.gov (United States)

    Butler, L.; Turney, D.; Matiella Novak, A.; Smith, D.; Simon, M.

    2013-12-01

    How's the weather in space? Why on Earth did NASA send two satellites above Earth to study radiation belts and space weather? To learn the answer to questions about NASA's Van Allen Probes mission, 450 students and their teachers from Maryland middle schools attended Space Academy events highlighting the Van Allen Probes mission. Sponsored by the Applied Physics Laboratory (APL) and Discovery Education, the events are held at the APL campus in Laurel, MD. Space Academies take students and teachers on behind-the-scenes exploration of how spacecraft are built, what they are designed to study, and introduces them to the many professionals that work together to create some of NASA's most exciting projects. Moderated by a public relations representative in the format of an official NASA press conference, the daylong event includes a student press conference with students as reporters and mission experts as panelists. Lunch with mission team members gives students a chance to ask more questions. After lunch, students don souvenir clean room suits, enjoy interactive science demonstrations, and tour APL facilities where the Van Allen Probes were built and tested before launch. Students may even have an opportunity to peek inside a clean room to view spacecraft being assembled. Prior to the event, teachers are provided with classroom activities, lesson plans, and videos developed by APL and Discovery Education to help prepare students for the featured mission. The activities are aligned to National Science Education Standards and appropriate for use in the classroom. Following their visit, student journalists are encouraged to write a short article about their field trip; selections are posted on the Space Academy web site. Designed to engage, inspire, and influence attitudes about space science and STEM careers, Space Academies provide an opportunity to attract underserved populations and emphasize that space science is for everyone. Exposing students to a diverse group of

  4. Parylene-based active micro space radiator with thermal contact switch

    Science.gov (United States)

    Ueno, Ai; Suzuki, Yuji

    2014-03-01

    Thermal management is crucial for highly functional spacecrafts exposed to large fluctuations of internal heat dissipation and/or thermal boundary conditions. Since thermal radiation is the only means for heat removal, effective control of radiation is required for advanced space missions. In the present study, a MEMS (Micro Electro Mechanical Systems) active radiator using the contact resistance change has been proposed. Unlike previous bulky thermal louvers/shutters, higher fill factor can be accomplished with an array of electrostatically driven micro diaphragms suspended with polymer tethers. With an early prototype developed with parylene MEMS technologies, radiation heat flux enhancement up to 42% has been achieved.

  5. The Nasa space radiation school, an excellent training in radiobiology and space radiation protection; La NASA space radiation summer school, une formation d'excellence en radiobiologie et radioprotection spatiale

    Energy Technology Data Exchange (ETDEWEB)

    Vogin, G. [Centre Alexis-Vautrin, 54 - Nancy (France)

    2009-10-15

    The astronauts have to spend more time in space and the colonization of the moon and Mars are in the cross hairs of international agencies. The cosmic radiation from which we are protected on ground by atmosphere and by the terrestrial magnetosphere (.4 mSv/year according to Who) become really threatening since 20 km altitude, delivering an average radiation dose of a therapeutic kind to astronauts with peaks related to solar events. It is composed in majority of hadrons: protons (85%) and heavy ions (13%), but also photons (2%) of high energy (GeV/n)). the incurred risks are multiple: early ones(cataract, central nervous system damages, whole body irradiation) but especially delayed ones (carcinogenesis). The astronauts radiation protection turns poor and the rate of death risk by cancer returning from a mission on Mars has been estimated at 5%. The Nasa created in 2004 a summer school aiming to awareness young researchers to the space radiobiology specificities. Areas concerned as follow: radioinduced DNA damage and repair, cell cycle, apoptosis, bystander effect, genome instability, neuro degeneration, delayed effects and carcinogenesis in relation with radiation exposure. (N.C.)

  6. Radiation Environment in EARTH-MOON Space: Results from Radom Experiment Onboard CHANDRAYAAN-1

    Science.gov (United States)

    Vadawale, S. V.; Goswami, J. N.; Dachev, T. P.; Tomov, B. T.; Girish, V.

    2011-07-01

    The radiation monitor (RADOM) payload is a miniature dosimeter spectrometer onboard Chandrayaan-1 mission for monitoring the local radiation environment in near-Earth space and in lunar space. RADOM measured the total absorbed dose and spectrum of the deposited energy from high-energy particles in near-Earth space, en-route and in lunar orbit. RADOM was the first experiment to be switched on soon after the launch of Chandrayaan-1 and was operational till the end of the mission. This article summarizes the observations carried out by RADOM during the entire life time of the Chandrayaan-1 mission and some of the salient results.

  7. Radiation resistance of thin-film solar cells for space photovoltaic power

    Science.gov (United States)

    Woodyard, James R.; Landis, Geoffrey A.

    1991-01-01

    Copper indium diselenide, cadmium telluride, and amorphous silicon alloy solar cells have achieved noteworthy performance and are currently being studied for space power applications. Cadmium sulfide cells had been the subject of much effort but are no longer considered for space applications. A review is presented of what is known about the radiation degradation of thin film solar cells in space. Experimental cadmium telluride and amorphous silicon alloy cells are reviewed. Damage mechanisms and radiation induced defect generation and passivation in the amorphous silicon alloy cell are discussed in detail due to the greater amount of experimental data available.

  8. Fiber Optic Cable Assemblies for Space Flight 2: Thermal and Radiation Effects

    Science.gov (United States)

    Ott, Melanie N.

    1998-01-01

    Goddard Space Flight Center is conducting a search for space flight worthy fiber optic cable assemblies that will benefit all projects at all of the NASA centers. This paper is number two in a series of papers being issued as a result of this task to define and qualify space grade fiber optic cable assemblies. Though to qualify and use a fiber optic cable in space requires treatment of the cable assembly as a system, it is very important to understand the design and behavior of its parts. This paper addresses that need, providing information on cable components shrinkage testing and radiation testing results from recent experiments at Goddard Space Flight Center.

  9. Electric energy saving using natural illumination, in educational spaces; Ahorro de energia electrica utilizando iluminacion natural, en espacios educativos

    Energy Technology Data Exchange (ETDEWEB)

    Alpuche, Maria G; Marincic, Irene; Ochoa, Jose M [Programa de Arquitectura, Universidad de Sonora (Mexico)

    2008-07-15

    In this article the natural illumination in a space pertaining to the building of Architecture of the University of Sonora, in the city of Hermosillo is analyzed, Located towards the Northeast facade. This same space is repeated in the South facade, and paradoxically the space has the same dimensions and the same luminance design. Also the simulation of natural illumination by means of the Ecotec program is realized, and the levels of natural illumination in educational spaces, corresponding to the facilities of the University of Sonora are analyzed, where most of the year there is a completely clear sky. [Spanish] En este articulo se analiza la iluminacion natural en un espacio correspondiente al edificio de Arquitectura de la Universidad de sonora, en la ciudad de Hermosillo, Ubicado hacia la fachada Noreste. Este mismo espacio se repite en la fachada Sur, y el espacio tienen las mismas dimensiones y paradojicamente, el mismo diseno luminico. Tambien se realiza la simulacion de iluminacion natural mediante el programa Ecotec, y se analizan los niveles de iluminacion natural en espacios educativos, correspondientes a las instalaciones de la Universidad de Sonora, donde la mayor parte del ano se cuenta con un cielo completamente despejado.

  10. Radiation in Space and Its Control of Equilibrium Temperatures in the Solar System

    Science.gov (United States)

    Juhasz, Albert J.

    2004-01-01

    The problem of determining equilibrium temperatures for reradiating surfaces in space vacuum was analyzed and the resulting mathematical relationships were incorporated in a code to determine space sink temperatures in the solar system. A brief treatment of planetary atmospheres is also included. Temperature values obtained with the code are in good agreement with available spacecraft telemetry and meteorological measurements for Venus and Earth. The code has been used in the design of space power system radiators for future interplanetary missions.

  11. Development of Countermeasure and Application technologies to Space Radiation

    International Nuclear Information System (INIS)

    Lee, Ju Woon; Byun, Myung Woo; Kim, Jae Hun

    2009-02-01

    Basic studies to evaluate the microbial activity changes by irradiation, and identify the composting microorganisms using the hyperthermal composter were conducted. And establishment of research protocols on muscle atrophy mechanism using two-dimensional electrophoresis and various blotting analyses are conducted. And two bio-active molecules that potentially play an preventive role of muscle atrophy are uncovered. Integrative protocols linking between the effect of bio-active molecules and treadmill exercise for muscle atrophy inhibition are established. And, successful induction of hibernation-like animation (reduction in body temperature and heartbeat rate) were monitored after HIT injection to mice. The space Bibimbap was developed by a combination treatment of 0.4% baking powder, soaking for 45 min, cooking, freezing, and packaging. It could be consumed easily after rehydration for 10 with 70 .deg. C water, which can be supplied from the International Space Station. And Bulgogi steak developed by combination treatment of packaging, freezing, antioxidant, charcoal and irradiation is a ready-to-eat type and has long shelf-life at the room temperature. Four foods items (Kimchi, Ramen, Saengshik bar, Sujeonggwa) were certified for the use in space flight conditions of 30 days by IBMP to be supplied to the first Korean astronaut, So-Yeon Lee, who accomplished space missions (sensory comparison test) at the International Space Station in 2008. To participate in the nutritional and physiological evaluation of Korean space foods in the MARS-500 project and evaluation of growth change in radio-durable micro organisms and plant seeds by space flight using BION-M1 satellite, a series of meeting were held in Russia and Korea

  12. Development of Countermeasure and Application technologies to Space Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Woon; Byun, Myung Woo; Kim, Jae Hun

    2009-02-15

    Basic studies to evaluate the microbial activity changes by irradiation, and identify the composting microorganisms using the hyperthermal composter were conducted. And establishment of research protocols on muscle atrophy mechanism using two-dimensional electrophoresis and various blotting analyses are conducted. And two bio-active molecules that potentially play an preventive role of muscle atrophy are uncovered. Integrative protocols linking between the effect of bio-active molecules and treadmill exercise for muscle atrophy inhibition are established. And, successful induction of hibernation-like animation (reduction in body temperature and heartbeat rate) were monitored after HIT injection to mice. The space Bibimbap was developed by a combination treatment of 0.4% baking powder, soaking for 45 min, cooking, freezing, and packaging. It could be consumed easily after rehydration for 10 with 70 .deg. C water, which can be supplied from the International Space Station. And Bulgogi steak developed by combination treatment of packaging, freezing, antioxidant, charcoal and irradiation is a ready-to-eat type and has long shelf-life at the room temperature. Four foods items (Kimchi, Ramen, Saengshik bar, Sujeonggwa) were certified for the use in space flight conditions of 30 days by IBMP to be supplied to the first Korean astronaut, So-Yeon Lee, who accomplished space missions (sensory comparison test) at the International Space Station in 2008. To participate in the nutritional and physiological evaluation of Korean space foods in the MARS-500 project and evaluation of growth change in radio-durable micro organisms and plant seeds by space flight using BION-M1 satellite, a series of meeting were held in Russia and Korea

  13. Web-based description of the space radiation environment using the Bethe-Bloch model

    Science.gov (United States)

    Cazzola, Emanuele; Calders, Stijn; Lapenta, Giovanni

    2016-01-01

    Space weather is a rapidly growing area of research not only in scientific and engineering applications but also in physics education and in the interest of the public. We focus especially on space radiation and its impact on space exploration. The topic is highly interdisciplinary, bringing together fundamental concepts of nuclear physics with aspects of radiation protection and space science. We give a new approach to presenting the topic by developing a web-based application that combines some of the fundamental concepts from these two fields into a single tool that can be used in the context of advanced secondary or undergraduate university education. We present DREADCode, an outreach or teaching tool to rapidly assess the current conditions of the radiation field in space. DREADCode uses the available data feeds from a number of ongoing space missions (ACE, GOES-13, GOES-15) to produce a first order approximation of the radiation dose an astronaut would receive during a mission of exploration in deep space (i.e. far from the Earth’s shielding magnetic field and from the radiation belts). DREADCode is based on an easy-to-use GUI interface available online from the European Space Weather Portal (www.spaceweather.eu/dreadcode). The core of the radiation transport computation to produce the radiation dose from the observed fluence of radiation observed by the spacecraft fleet considered is based on a relatively simple approximation: the Bethe-Bloch equation. DREADCode also assumes a simplified geometry and material configuration for the shields used to compute the dose. The approach is approximate and sacrifices some important physics on the altar of rapid execution time, which allows a real-time operation scenario. There is no intention here to produce an operational tool for use in space science and engineering. Rather, we present an educational tool at undergraduate level that uses modern web-based and programming methods to learn some of the most important

  14. Web-based description of the space radiation environment using the Bethe–Bloch model

    International Nuclear Information System (INIS)

    Cazzola, Emanuele; Lapenta, Giovanni; Calders, Stijn

    2016-01-01

    Space weather is a rapidly growing area of research not only in scientific and engineering applications but also in physics education and in the interest of the public. We focus especially on space radiation and its impact on space exploration. The topic is highly interdisciplinary, bringing together fundamental concepts of nuclear physics with aspects of radiation protection and space science. We give a new approach to presenting the topic by developing a web-based application that combines some of the fundamental concepts from these two fields into a single tool that can be used in the context of advanced secondary or undergraduate university education. We present DREADCode, an outreach or teaching tool to rapidly assess the current conditions of the radiation field in space. DREADCode uses the available data feeds from a number of ongoing space missions (ACE, GOES-13, GOES-15) to produce a first order approximation of the radiation dose an astronaut would receive during a mission of exploration in deep space (i.e. far from the Earth’s shielding magnetic field and from the radiation belts). DREADCode is based on an easy-to-use GUI interface available online from the European Space Weather Portal (www.spaceweather.eu/dreadcode). The core of the radiation transport computation to produce the radiation dose from the observed fluence of radiation observed by the spacecraft fleet considered is based on a relatively simple approximation: the Bethe–Bloch equation. DREADCode also assumes a simplified geometry and material configuration for the shields used to compute the dose. The approach is approximate and sacrifices some important physics on the altar of rapid execution time, which allows a real-time operation scenario. There is no intention here to produce an operational tool for use in space science and engineering. Rather, we present an educational tool at undergraduate level that uses modern web-based and programming methods to learn some of the most

  15. Representing Mental Spaces and Dynamics of Natural Language Semantics

    Directory of Open Access Journals (Sweden)

    Ramin Golshaie

    2011-01-01

    Full Text Available

    Building systems with the robustness of human reasoning capabilities requires inspirations from cognitive science.  The primary objective of this study is to investigate the possibility of representing some basic principles of cognitive semantics’ Mental Spaces Theory such as domain construction, reality status of domains and their elements, and mental attitudes in a knowledge representation framework for the purpose of developing cognitively plausible knowledge representation systems. The model used as the basis of representation is the extended version of conventional semantic networks, namely Multi-Layered Extended Semantic Networks (MultiNet. The data used in this study have been selected from English expressions and have been represented in MWR, MultiNet’s knowledge representation software. Results obtained from analysis of represented data and their comparison to principles of mental spaces theory shows that theoretical constructs of mental spaces theory such as domain construction, reality status of domains and their elements, and mental attitudes can be formally represented in the MultiNet framework.

  16. Experimental Studies of Carbon Nanotube Materials for Space Radiators

    Science.gov (United States)

    SanSoucie, MIchael P.; Rogers, Jan R.; Craven, Paul D.; Hyers, Robert W.

    2012-01-01

    Game ]changing propulsion systems are often enabled by novel designs using advanced materials. Radiator performance dictates power output for nuclear electric propulsion (NEP) systems. Carbon nanotubes (CNT) and carbon fiber materials have the potential to offer significant improvements in thermal conductivity and mass properties. A test apparatus was developed to test advanced radiator designs. This test apparatus uses a resistance heater inside a graphite tube. Metallic tubes can be slipped over the graphite tube to simulate a heat pipe. Several sub ]scale test articles were fabricated using CNT cloth and pitch ]based carbon fibers, which were bonded to a metallic tube using an active braze material. The test articles were heated up to 600 C and an infrared (IR) camera captured the results. The test apparatus and experimental results are presented here.

  17. Utilization of natural polysaccharides by radiation in Korea

    International Nuclear Information System (INIS)

    Lee, Young Keun; Young Chang Nho

    2001-01-01

    Radiation can induce a chemical reaction to modify polymer under even solid conditions or in low temperatures. Radiation crosslinking can be easily adjusted and is easily reproducible by controlling the radiation dose. The finished product contains no residues of substances required to initiate the chemical crosslinking which can restrict the application possibilities. In these studies, hydrogels from a mixture of chitosan and polyvinyl alcohol (PVA)/Poly-N-vinylpyrrolidone (PVP) were made by 'freezing and thawing', or gamma-ray irradiation or two steps of 'freezing and thawing' and gamma-ray irradiation for wound dressing. Mechanical properties such as gelation, water absorptivity, and gel strength were examined to evaluate the hydrogels for wound dressing. The composition of PVA:PVP was 60:40, PVA/PVP: chitosan ratio was in the range 9:1 - 7:3, and the solid concentration of PVA/PVP/chitosan solution was 15wt%. Gamma irradiation doses of 25, 35,50, 60 and 70kGy were exposed to a mixture of PVA/PVP/chitosan to evaluate the effect of irradiation dose on the mechanical properties of hydrogels. Water-soluble chitosan was used in this experiment. The gelation of hydrogels was higher when two steps of 'freezing and thawing' and irradiation were used than when only 'freezing and thawing' was utilized. Gel content was influenced slightly by PVA/PVP: chitosan composition and irradiation dose, but swelling was influenced greatly by them. The swelling percent was much increased as the composition of chitosan in PVA/PVP/chitosan increased. (author)

  18. Urbanization effects on natural radiation in anomalous areas

    International Nuclear Information System (INIS)

    Affonseca, M.S. de.

    1993-10-01

    The urbanization effects and their possible causes on the environmental gamma radiation levels, in an anomalous area, were studied. The field work was accomplished in Guarapari, located in the seacoast of the Brazilian state of Espirito Santo, which is rich in monazite sands, with thorium and uranium contents. The results show clearly that there was a reduction in the levels of external exposition in the streets and squares of Guarapari. It was ascertained that the reduction was due to the materials used in the urbanization. (L.C.J.A.)

  19. Enhanced natural radiation exposure enhanced by human activity: the largest contributor to the Chinese population dose

    International Nuclear Information System (INIS)

    Pan Ziqiang; Liu Yanyang

    2011-01-01

    For the radiation exposure caused by human activities, the enhanced natural radiation exposure is the largest contributor to Chinese population dose. This problem has attracted social attention in recent years. Efforts have been made in several fields, such as radon indoors and in workplace, environmental problems associated with NORMs, occupational radiation hazards of non-uranium mine, and radiation dose evaluation for energy chain, but there are still many problems to be solved. In order to protect the health of workers and the public, while ensuring industrial production and economic development, it is also necessary to continue to strengthen research in all aspects above mentioned, and gradually promote the control of natural radiation exposure enhanced by human activities. (authors)

  20. Initial Efforts in Characterizing Radiation and Plasma Effects on Space Assets: Bridging the Space Environment, Engineering and User Community

    Science.gov (United States)

    Zheng, Y.; Ganushkina, N. Y.; Guild, T. B.; Jiggens, P.; Jun, I.; Mazur, J. E.; Meier, M. M.; Minow, J. I.; Pitchford, D. A.; O'Brien, T. P., III; Shprits, Y.; Tobiska, W. K.; Xapsos, M.; Rastaetter, L.; Jordanova, V. K.; Kellerman, A. C.; Fok, M. C. H.

    2017-12-01

    The Community Coordinated Modeling Center (CCMC) has been leading the community-wide model validation projects for many years. Such effort has been broadened and extended via the newly-launched International Forum for Space Weather Modeling Capabilities Assessment (https://ccmc.gsfc.nasa.gov/assessment/), Its objective is to track space weather models' progress and performance over time, which is critically needed in space weather operations. The Radiation and Plasma Effects Working Team is working on one of the many focused evaluation topics and deals with five different subtopics: Surface Charging from 10s eV to 40 keV electrons, Internal Charging due to energetic electrons from hundreds keV to several MeVs. Single Event Effects from solar energetic particles (SEPs) and galactic cosmic rays (GCRs) (several MeV to TeVs), Total Dose due to accumulation of doses from electrons (>100 KeV) and protons (> 1 MeV) in a broad energy range, and Radiation Effects from SEPs and GCRs at aviation altitudes. A unique aspect of the Radiation and Plasma Effects focus area is that it bridges the space environments, engineering and user community. This presentation will summarize the working team's progress in metrics discussion/definition and the CCMC web interface/tools to facilitate the validation efforts. As an example, tools in the areas of surface charging/internal charging will be demoed.

  1. Radiation processing of natural rubber and its applications

    International Nuclear Information System (INIS)

    Dahlan Hj. Mohd

    2007-01-01

    Research in natural rubber (NR) is still offering good and exciting opportunities especially in making NR into superior products and as a source for new chemicals by modification of its structure. As in the case of liquid epoxidised natural rubber acrylic (LENRA), it has been shown that it has the ability to induce the interfacial interaction between NR and polyolefin i.e. High-density polyethylene (HDPE) as demonstrated by Transmission Electron Microscopy (TEM) and small angle neutron scattering (SANS) techniques. For NR/HDPE blend, without deuteration technique, SANS was also to induce some scattering data leading to fruitful information on the interfacial interaction between the blend compositions. (author)

  2. Proceedings of the Takasaki symposium on radiation processing of natural polymers

    International Nuclear Information System (INIS)

    Kume, Tamikazu; Maekawa, Yasunari

    2001-03-01

    This Takasaki symposium was held as enlargement of the Takasaki workshop on bilateral cooperations for radiation processing of natural polymers in 1999. The attendants were increased from 61 to 80 due to the expansion from five bilateral cooperation countries last year to further 3 Asian countries. At the symposium, the enhancement effects of plant growth and antifungal activity by radiation-degraded carbohydrates, hydrogels as a wound dressing material, and production of an protein free natural rubber grove were of major concern. Many domestic and foreign attendants were especially interested in novel functionality of radiation treated natural polymers and exchanged their opinions actively. Furthermore, since outstanding researchers in this field were invited from the Asian countries, we could also exchange the opinions about the present situation of the research activities interregional cooperation of the radiation processing in Asia. The 27 of the presented papers are indexed individually. (J.P.N.)

  3. Effective Dose Equivalent To The Cypriot Population Due To Natural Radiation

    International Nuclear Information System (INIS)

    Christofides, S.

    1994-01-01

    A study was initiated by the Biomedical Research Foundation, two years ago, to estimate the various natural radiation components that contribute to the Effective Dose Equivalent (EDE) to the Cypriot population. The present study has shown that the contribution due to cosmic radiation is estimated to be less than 270 microSiverts per annum, while that due to airborne Rn-222 concentration in Cypriot houses is estimated to be less then 330 microSieverts per annum. The contribution due to terrestrial gamma radiations, which is currently under investigation, is so far estimated to be around 108 microSieverts per annum. Therefore the EDE to the Cypriot population due to natural radiation is likely to be around 700 microSieverts per annum, not taking into account the internal exposure due to other naturally occuring radionuclides. (author)

  4. Assessment of natural background radiation in one of the highest regions of Ecuador

    Science.gov (United States)

    Pérez, Mario; Chávez, Estefanía; Echeverría, Magdy; Córdova, Rafael; Recalde, Celso

    2018-05-01

    Natural background radiation was measured in the province of Chimborazo (Ecuador) with the following reference coordinates 1°40'00''S 78°39'00''W, where the furthest point to the center of the planet is located. Natural background radiation measurements were performed at 130 randomly selected sites using a Geiger Müller GCA-07W portable detector; these measurements were run at 6 m away from buildings or walls and 1 m above the ground. The global average natural background radiation established by UNSCEAR is 2.4 mSv y-1. In the study area measurements ranged from 0.57 mSv y-1 to 3.09 mSv y-1 with a mean value of 1.57 mSv y-1, the maximum value was recorded in the north of the study area at 5073 metres above sea level (m.a.s.l.), and the minimum value was recorded in the southwestern area at 297 m.a.s.l. An isodose map was plotted to represent the equivalent dose rate due to natural background radiation. An analysis of variance (ANOVA) between the data of the high and low regions of the study area showed a significant difference (p < α), in addition a linear correlation coefficient of 0.92 was obtained, supporting the hypothesis that in high altitude zones extraterrestrial radiation contributes significantly to natural background radiation.

  5. Annual Conference on Nuclear and Space Radiation Effects, Gatlinburg, TN, July 18-21, 1983, Proceedings

    Science.gov (United States)

    1983-01-01

    Topics discussed include radiation effects in devices; the basic mechanisms of radiation effects in structures and materials; radiation effects in integrated circuits; spacecraft charging and space radiation effects; hardness assurance for devices and systems; and radiation transport, energy deposition and charge collection. Papers are presented on the mechanisms of small instabilities in irradiated MOS transistors, on the radiation effects on oxynitride gate dielectrics, on the discharge characteristics of a simulated solar cell array, and on latchup in CMOS devices from heavy ions. Attention is also given to proton upsets in orbit, to the modeling of single-event upset in bipolar integrated circuits, to high-resolution studies of the electrical breakdown of soil, and to a finite-difference solution of Maxwell's equations in generalized nonorthogonal coordinates.

  6. Annual Conference on Nuclear and Space Radiation Effects, Gatlinburg, TN, July 18-21, 1983, Proceedings

    Science.gov (United States)

    1983-12-01

    Topics discussed include radiation effects in devices; the basic mechanisms of radiation effects in structures and materials; radiation effects in integrated circuits; spacecraft charging and space radiation effects; hardness assurance for devices and systems; and radiation transport, energy deposition and charge collection. Papers are presented on the mechanisms of small instabilities in irradiated MOS transistors, on the radiation effects on oxynitride gate dielectrics, on the discharge characteristics of a simulated solar cell array, and on latchup in CMOS devices from heavy ions. Attention is also given to proton upsets in orbit, to the modeling of single-event upset in bipolar integrated circuits, to high-resolution studies of the electrical breakdown of soil, and to a finite-difference solution of Maxwell's equations in generalized nonorthogonal coordinates. For individual items see A84-20677 to A84-20743

  7. 1988 IEEE Annual Conference on Nuclear and Space Radiation Effects, 25th, Portland, OR, July 12-15, 1988, Proceedings

    Science.gov (United States)

    Coakley, Peter G. (Editor)

    1988-01-01

    The effects of nuclear and space radiation on the performance of electronic devices are discussed in reviews and reports of recent investigations. Topics addressed include the basic mechanisms of radiation effects, dosimetry and energy-dependent effects, sensors in and for radiation environments, EMP/SGEMP/IEMP phenomena, radiation effects on isolation technologies, and spacecraft charging and space radiation effects. Consideration is given to device radiation effects and hardening, hardness assurance and testing techniques, IC radiation effects and hardening, and single-event phenomena.

  8. Instrument and spacecraft faults associated with nuclear radiation in space

    Science.gov (United States)

    Trainos, J. H.

    1994-01-01

    A review is given which surveys the variety of faults and failures which have occurred in space due both to the effects of single, energetic nuclear particles, as well as effects due to the accumulated ionizing dose or the fluence of nuclear particles. The review covers a variety of problems with sensors, electronics, instruments and spacecraft from several countries.

  9. Exposure of space electronics and materials to ionizing radiation

    DEFF Research Database (Denmark)

    Korsbech, Uffe C C

    1996-01-01

    Describes the methods and sources available for irradiation of space instruments developed at the Department of Automation. Methods for calculations and measurements of fluences and doses are also described. The sources are gamma-rays from iridium-192 and cobalt-60, 30 MeV protons, 10 MeV electrons...

  10. Measurement of the natural radiation environment and its dependence on various parameters in Austria and assessment of the natural external and internal radiation dose of various population groups

    International Nuclear Information System (INIS)

    Pohl, E.

    1978-06-01

    The natural mean values of natural radionuclides in the air and external gamma radiation were determined from measurements carried out in various parts of Austria and the mean values were used as a basis for the determination of body and organ doses. Moreover frequency distributions of several specific organ doses within various population groups were investigated. Measurements of natural air activity were carried out indoors and outdoors as well as gamma radiation at the following sites - Salzburg Town, Badgastein, Gastein Valley and Mallnitz and several other places at a line crossing the Alps from South to North (Corinthia, Schwarzach, Forstau, Hallein, Kuchl, Grodig and Voggenberg - Bergheim) and in 15 different mines in the Counties of Salzburg and Upper Austria. The methods of calculation of the radiation burden due to inhalation is published in the Proceedings of the Symposium on Biological and Environmental Effects of Low Level Radiation, IAEA, Chicago 1976, Vol. II pages 305-315. It can be concluded from the work that great local differences of some components occur even within relatively small areas. The radioactivity in the air shows great temporal differences at one and the same site. In addition radiation doses had to be calculated separately for various organs and tissues due to the inhomogeneous distribution of doses within the body. Also the estimation had to be made for a variety of individuals depending on sex, age, weight and various physiological states of activity. The highest doses to tissues from inhalation of natural radioactivity are the basal cells of the sigmental epithelium and subsigmental bronchi 4th - 9th generation in the lung model of Weibel. 46% of the population investigated received more than 0.5 rem per year, 25% more than 1.5 rem per year and 1.3% more than 3 rem per year. The different air activities in the living and working rooms are due to differences in the building materials and in the construction of houses

  11. Radiation-induced paramagnetic species in natural calcite speleothems

    International Nuclear Information System (INIS)

    Rossi, A.M.; Poupeau, G.

    1989-01-01

    The ESR natural spectrum of humic-free speleothem calcite single crytals in the region of g = 2.0000 is a composite of lines from 4 radiogenic species, in addition to Mn ++ lines. Laboratory irradiation causes appearrance of three more species. Use of isotropic F species (g = 2.0003) for dating is possible if specific cautions are followed. (author) [pt

  12. Space Radiation Measurement on the Polar Route onboard the Korean Commercial Flights

    Directory of Open Access Journals (Sweden)

    Junga Hwang

    2010-03-01

    Full Text Available This study was performed by the policy research project of Ministry of Land, Transport and Maritime Affairs, which title is “Developing safety standards and management of space radiation on the polar route”. In this research, total six experiments were performed using Korean commercial flights (B747. Three of those are on the polar route and the other three are on the north pacific route. Space radiation exposure measured on the polar route is the average 84.7 uSv. The simulation result using CARI-6M program gives 84.9 uSv, which is very similar to measured value. For the departure flight using the north pacific route, the measured space radiation is the average 74.4 uSv. It seems that is not so different to use the polar route or not for the return flight because the higher latitude effect causing the increase of space radiation is compensated by the shortened flight time effect causing decreasing space radiation exposure.

  13. Effect of radiation dose on the properties of natural rubber nanocomposite

    International Nuclear Information System (INIS)

    Khalid, M.; Ismail, A.F.; Ratnam, C.T.; Faridah, Y.; Rashmi, W.; Al Khatib, M.F.

    2010-01-01

    Effect of radiation dose and carbon nanotubes (CNT) on the mechanical properties of standard Malaysian rubber (SMR) was investigated in this study. SMR nanocomposites containing 1-7 phr CNT were prepared using the solvent casting method and the nanocomposites were radiated at doses of 50-200 kGy. The change in mechanical properties, especially, tensile strength (Ts), elongation at break (Eb), hardness and tensile modulus at 100% elongation (M 100 ) were studied as a function of radiation dose. The structure and morphology of reinforced natural rubber was investigated by FESEM, TEM and AFM in order to gain further evidence on the radiation-induced crosslinking. It was found that the Ts, M 100 and the hardness of the SMR/CNT nanocomposites significantly increased with radiation dose; the elongation at break exhibited an increase up to 100 kGy, and a downward trend thereafter. Results on gel fraction further confirmed the crosslinking of SMR/CNT nanocomposites upon radiation.

  14. ENSO impact on surface radiative fluxes as observed from space

    Science.gov (United States)

    Pinker, R. T.; Grodsky, S. A.; Zhang, B.; Busalacchi, A.; Chen, W.

    2017-10-01

    We investigate the impact of El Niño-Southern Oscillation (ENSO) on surface radiative fluxes over the tropical Pacific using satellite observations and fluxes derived from selected atmospheric reanalyses. Agreement between the two in this region is important because reanalysis information is frequently used to assess surface energy budget sensitivity to ENSO. We found that during the traditional ENSO, the maximum variance of anomalous incoming solar radiation is located just west of the dateline and coincides with the area of the largest anomalous SST gradient. It can reach up to 60 W/m2 and lags behind the Niño3 index by about a month, suggesting a response to anomalous SST gradient. The magnitude of longwave anomaly is only half that large and varies in phase with the SST anomaly. Similar anomalies were derived from outputs: from the European Centre for Medium-Weather Forecasts Reanalysis Interim (ERA-I), from the Modern Era Retrospective Analysis version 2 (MERRA-2), from the NCEP/NCAR Reanalysis 1 (R1), and from the Japanese JRA55 reanalysis. Among the four reanalyses used, results from ERA-I are the closest to observations. We have also investigated the surface wind divergence/convergence and found that the main factor limiting eastward excursions of convection is the surface wind convergence. Due to the wind divergence pattern normally present over the eastern cold tongue, anomalous convection extends into the eastern equatorial Pacific only during the strongest warm events. Our analysis also considers the El Niño Modoki events, for which the radiation flux patterns are shifted westward following the SST pattern.

  15. A novel radiation hard pixel design for space applications

    Science.gov (United States)

    Aurora, A. M.; Marochkin, V. V.; Tuuva, T.

    2017-11-01

    We have developed a novel radiation hard photon detector concept based on Modified Internal Gate Field Effect Transistor (MIGFET) wherein a buried Modified Internal Gate (MIG) is implanted underneath a channel of a FET. In between the MIG and the channel of the FET there is depleted semiconductor material forming a potential barrier between charges in the channel and similar type signal charges located in the MIG. The signal charges in the MIG have a measurable effect on the conductance of the channel. In this paper a radiation hard double MIGFET pixel is investigated comprising two MIGFETs. By transferring the signal charges between the two MIGs Non-Destructive Correlated Double Sampling Readout (NDCDSR) is enabled. The radiation hardness of the proposed double MIGFET structure stems from the fact that interface related issues can be considerably mitigated. The reason for this is, first of all, that interface generated dark noise can be completely avoided and secondly, that interface generated 1/f noise can be considerably reduced due to a deep buried channel readout configuration. Electrical parameters of the double MIGFET pixel have been evaluated by 3D TCAD simulation study. Simulation results show the absence of interface generated dark noise, significantly reduced interface generated 1/f noise, well performing NDCDSR operation, and blooming protection due to an inherent vertical anti-blooming structure. In addition, the backside illuminated thick fully depleted pixel design results in low crosstalk due to lack of diffusion and good quantum efficiency from visible to Near Infra-Red (NIR) light. These facts result in excellent Signal-to-Noise Ratio (SNR) and very low crosstalk enabling thus excellent image quality. The simulation demonstrates the charge to current conversion gain for source current read-out to be 1.4 nA/e.

  16. Annual Conference on Nuclear and Space Radiation Effects, 16th, Santa Cruz, Calif., July 17-20, 1979, Proceedings

    Science.gov (United States)

    Bombardt, J.

    1979-01-01

    Papers are presented on the following topics: radiation effects in bipolar microcircuits; basic radiation mechanisms in materials and devices; energy deposition and dosimetry; and system responses from SGEMP, IEMP, and EMP. Also considered are basic processes in SGEMP and IEMP, radiation effects in MOS microcircuits, and space radiation effects and spacecraft charging.

  17. Technology transfer on radiation processing of natural polymer in Japan

    International Nuclear Information System (INIS)

    Yoshii, Fumio

    2007-01-01

    Carboxymethyl cellulose (CMC) crosslinked at paste-like condition forms hydrogel. The hydrogel was applied as a coolant to keep flesh of vegetables and fish at low temperature. Shochu (Japanese liquor of 25% alcohol content) residue produced by fermentation of rice and sweet potato was rapidly converted to animal feed by water absorption of CMC dry gel. Poly(lactic acid) crosslinked by irradiation in the presence of triallyl isocyanurate, TAIC was soaked in plasticizer to give softness. A maximum of 60 wt% plasticizer was incorporated in PLA resin and flexible PLA sheet was obtained. Growth of flowers was accelerated when sprayed with radiation degraded alginate shipment schedule of the flowers was advanced to one week. (author)

  18. Extractable protein of radiation vulcanized natural rubber latex

    Energy Technology Data Exchange (ETDEWEB)

    Soebianto, Y.S. [Center for Research and Development of Isotopes and Radiation Technology, BATAN, Jakarta (Indonesia); Upul, R.M. [Rubber Research Institute of Sri Lanka, Ratmalana (Sri Lanka); Makuuchi, K.; Yoshii, F.; Kume, T. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2000-03-01

    A new method to reduce the protein level in the latex products by irradiation is reported. Water soluble protein (WSP) solution (10%) was added into radiation vulcanized NR latex (RVNRL) as much as 3 phr in three different processes: added to RVNRL, added to re-centrifuged RVNRL, and added to RVNRL followed by centrifugation. The protein content was determined by enhanced BCA method, and identified by SDS-PAGE analysis. Addition of WSP followed by centrifugation reduces EP up to the minimum protein detection, and shortens the leaching time to 20-30 min. SDS-PAGE analysis confirms the reduction of soluble protein in the serum phase, and disappearance of protein bands in the rubber extract. Protein-WSP interaction produces water soluble complex, and removed by centrifugation. The molecular weight of WSP dictates the efficiency of protein removal. (author)

  19. Radiation pressure dynamics in planetary exospheres - a natural framework

    International Nuclear Information System (INIS)

    Bishop, J.; Chamberlain, J.W.

    1989-01-01

    Exospheric theory is reformulated to provide for the analysis of dynamical underpinning of exospheric features. The formulation is based on the parabolic-cylindrical separability of the Hamiltonian that describes particle motions in the combined fields of planetary gravity and solar radiation pressure. An approximate solution for trajectory evolution in terms of orbital elements is derived and the role of the exopause in the tail phenomenon is discussed. Also, an expression is obtained for the bound constituent atom densities at outer planetocoronal positions along the planet-sun axis for the case of an evaporative, uniform exobase. This expression is used to estimate midnight density enhancements as a function of radial distance for the terrestrial planets. 19 refs

  20. Extractable protein of radiation vulcanized natural rubber latex

    International Nuclear Information System (INIS)

    Soebianto, Y.S.; Upul, R.M.; Makuuchi, K.; Yoshii, F.; Kume, T.

    2000-01-01

    A new method to reduce the protein level in the latex products by irradiation is reported. Water soluble protein (WSP) solution (10%) was added into radiation vulcanized NR latex (RVNRL) as much as 3 phr in three different processes: added to RVNRL, added to re-centrifuged RVNRL, and added to RVNRL followed by centrifugation. The protein content was determined by enhanced BCA method, and identified by SDS-PAGE analysis. Addition of WSP followed by centrifugation reduces EP up to the minimum protein detection, and shortens the leaching time to 20-30 min. SDS-PAGE analysis confirms the reduction of soluble protein in the serum phase, and disappearance of protein bands in the rubber extract. Protein-WSP interaction produces water soluble complex, and removed by centrifugation. The molecular weight of WSP dictates the efficiency of protein removal. (author)

  1. Improving Agricultural Productivity with Radiation Processed Natural Polymers

    International Nuclear Information System (INIS)

    Henriques, Sasha

    2013-01-01

    Full text: Through the power of irradiation to break and create chemical bonds, the natural polymer cassava starch is used to make super water absorbents (SWA), 1kg of which can absorb and hold 200 litres of water and release it slowly over time. Placed in the soil near plants’ roots, SWA can be used where there is little rain or frequent drought. After 9 months the crystals, which resemble sugar crystals, completely disintegrate, leaving no residue. (author)

  2. Human genetics studies in areas of high natural radiation, 7

    International Nuclear Information System (INIS)

    Freire-Maia, A.

    1975-01-01

    Two methods to estimate the inbreeding load, employed in our analysis, are reviewed. Besides the total population, a sample constituted of individuals with no alien ancestral is also analysed. The measurements by genetic load models show any clear effect of natural radioactivity (especially for abortions, pre-natal mortality, anomalies, and abnormalities in general). The results on stillbirths and post-natal and total mortalities are discussed and it is concluded that uncontrolled concomitant variables (if not chance alone) cause the differences [pt

  3. Radiation vulcanised natural rubber latex (RVNRL) market and challenges

    International Nuclear Information System (INIS)

    Wan Manshol Wan Zin; Najib Mohamad Zakey; Chai Chee Keong

    2000-01-01

    RVNRL has the required properties and proven useful for the manufacturing of examination gloves, balloons and finger cots at industrial scale. To date only RVNRL finger cots are available in the market. Problems and challenges for the market of other products are identified. Further success in the on going research activities will be the reference for more applications of RVNRL in the relevant industry to produce natural rubber latex products of more competitive values

  4. Thermally optimum spacing of vertical, natural convection cooled, parallel plates

    Science.gov (United States)

    Bar-Cohen, A.; Rohsenow, W. M.

    Vertical two-dimensional channels formed by parallel plates or fins are a frequently encountered configuration in natural convection cooling in air of electronic equipment. In connection with the complexity of heat dissipation in vertical parallel plate arrays, little theoretical effort is devoted to thermal optimization of the relevant packaging configurations. The present investigation is concerned with the establishment of an analytical structure for analyses of such arrays, giving attention to useful relations for heat distribution patterns. The limiting relations for fully-developed laminar flow, in a symmetric isothermal or isoflux channel as well as in a channel with an insulated wall, are derived by use of a straightforward integral formulation.

  5. Optimum space shuttle launch times relative to natural environment

    Science.gov (United States)

    King, R. L.

    1977-01-01

    Three sets of meteorological criteria were analyzed to determine the probabilities of favorable launch and landing conditions. Probabilities were computed for every 3 hours on a yearly basis using 14 years of weather data. These temporal probability distributions, applicable to the three sets of weather criteria encompassing benign, moderate and severe weather conditions, were computed for both Kennedy Space Center (KSC) and Edwards Air Force Base. In addition, conditional probabilities were computed for unfavorable weather conditions occurring after a delay which may or may not be due to weather conditions. Also, for KSC, the probabilities of favorable landing conditions at various times after favorable launch conditions have prevailed have been computed so that mission probabilities may be more accurately computed for those time periods when persistence strongly correlates weather conditions. Moreover, the probabilities and conditional probabilities of the occurrence of both favorable and unfavorable events for each individual criterion were computed to indicate the significance of each weather element to the overall result.

  6. Designed Natural Spaces: Informal Gardens Are Perceived to Be More Restorative than Formal Gardens.

    Science.gov (United States)

    Twedt, Elyssa; Rainey, Reuben M; Proffitt, Dennis R

    2016-01-01

    Experimental research shows that there are perceived and actual benefits to spending time in natural spaces compared to urban spaces, such as reduced cognitive fatigue, improved mood, and reduced stress. Whereas past research has focused primarily on distinguishing between distinct categories of spaces (i.e., nature vs. urban), less is known about variability in perceived restorative potential of environments within a particular category of outdoor spaces, such as gardens. Conceptually, gardens are often considered to be restorative spaces and to contain an abundance of natural elements, though there is great variability in how gardens are designed that might impact their restorative potential. One common practice for classifying gardens is along a spectrum ranging from "formal or geometric" to "informal or naturalistic," which often corresponds to the degree to which built or natural elements are present, respectively. In the current study, we tested whether participants use design informality as a cue to predict perceived restorative potential of different gardens. Participants viewed a set of gardens and rated each on design informality, perceived restorative potential, naturalness, and visual appeal. Participants perceived informal gardens to have greater restorative potential than formal gardens. In addition, gardens that were more visually appealing and more natural-looking were perceived to have greater restorative potential than less visually appealing and less natural gardens. These perceptions and precedents are highly relevant for the design of gardens and other similar green spaces intended to provide relief from stress and to foster cognitive restoration.

  7. Proceedings of the FNCA 2006 workshop on application of electron accelerator. Radiation processing of natural polymer

    International Nuclear Information System (INIS)

    Tamada, Masao; Kume, Tamikazu

    2007-08-01

    This workshop was co-sponsored by the Ministry of Education, Culture, Sports, Science and Technology, Japan and the Ministry of Science, Technology and Innovation, Malaysia and jointly organized by the Japan Atomic Energy Agency and the Malaysian Nuclear Agency. The main objectives of the workshop were to discuss the commercial status of radiation processing of natural polymer in the participating countries and to prepare the work plan for the Forum for Nuclear Cooperation in Asia (FNCA) activities on radiation processing of natural polymer. The workshop was attended by experts on radiation processing from China, Indonesia, Japan, Korea, Malaysia, Philippines, Thailand and Vietnam. The radiation processing of natural polymer is divided into radiation crosslinking and degradation of polysaccharides. The radiation crosslinking of polysaccharides is mainly used to prepare hydrogel for healthcare and environment. Several hydrogels were commercialized in Korea, Japan and Malaysia, respectively. Hydrogels containing chitosan and carrageenan are currently in trial in China, Indonesia, Philippines and Vietnam. Cassava hydrogel is developing in Thailand. Radiation degraded chitosan is actually used in Vietnam and China in agriculture and aquaculture, respectively. Indonesia, Philippines and Thailand are trying in laboratory and pilot scale as plant growth promoter. All manuscripts submitted by every speaker were included in the proceedings. (author)

  8. MESTRN: A Deterministic Meson-Muon Transport Code for Space Radiation

    Science.gov (United States)

    Blattnig, Steve R.; Norbury, John W.; Norman, Ryan B.; Wilson, John W.; Singleterry, Robert C., Jr.; Tripathi, Ram K.

    2004-01-01

    A safe and efficient exploration of space requires an understanding of space radiations, so that human life and sensitive equipment can be protected. On the way to these sensitive sites, the radiation fields are modified in both quality and quantity. Many of these modifications are thought to be due to the production of pions and muons in the interactions between the radiation and intervening matter. A method used to predict the effects of the presence of these particles on the transport of radiation through materials is developed. This method was then used to develop software, which was used to calculate the fluxes of pions and muons after the transport of a cosmic ray spectrum through aluminum and water. Software descriptions are given in the appendices.

  9. Public evaluation of open space in Illinois: citizen support for natural area acquisition.

    Science.gov (United States)

    Backlund, Erik A; Stewart, William P; McDonald, Cary; Miller, Craig

    2004-11-01

    Numerous studies have indicated a broad-based support for open space preservation and protection. Research also has characterized the public values and rationale that underlie the widespread support for open space. In recognition of the widespread public support for open space, various levels of government have implemented programs to provide public access to open space. There are many different types of open space, ranging from golf courses, ball parks, wildlife areas, and prairies, to name a few. This paper addresses questions related to the types of open space that should be prioritized by planners and natural resource managers. The results of this study are based on a stratified random sample of 5000 households in Illinois that were sent a questionnaire related to their support for various types of open space. Through a comparatively simple action grid analysis, the open space types that should be prioritized for public access include forest areas, stream corridors, wildlife habitat, and lakes/ponds. These were the open space types rated of the highest importance, yet were also the open space types rated the lowest in respondent satisfaction. This kind of analysis does not require the technical expertise of other options for land-use prioritizations (e.g., conjoint analysis, contingent valuation), yet provides important policy directives for planners. Although open space funds often allow for purchase of developed sites such as golf courses, ball parks, and community parks, this study indicates that undeveloped (or nature-based) open space lands are most needed in Illinois.

  10. AlGaN UV LED and Photodiodes Radiation Hardness and Space Qualifications and Their Applications in Space Science and High Energy Density Physics

    Energy Technology Data Exchange (ETDEWEB)

    Sun, K. X.

    2011-05-31

    This presentation provides an overview of robust, radiation hard AlGaN optoelectronic devices and their applications in space exploration & high energy density physics. Particularly, deep UV LED and deep UV photodiodes are discussed with regard to their applications, radiation hardness and space qualification. AC charge management of UV LED satellite payload instruments, which were to be launched in late 2012, is covered.

  11. A Review of NASA's Radiation-Hardened Electronics for Space Environments Project

    Science.gov (United States)

    Keys, Andrew S.; Adams, James H.; Patrick, Marshall C.; Johnson, Michael A.; Cressler, John D.

    2008-01-01

    NASA's Radiation Hardened Electronics for Space Exploration (RHESE) project develops the advanced technologies required to produce radiation hardened electronics, processors, and devices in support of the requirements of NASA's Constellation program. Over the past year, multiple advancements have been made within each of the RHESE technology development tasks that will facilitate the success of the Constellation program elements. This paper provides a brief review of these advancements, discusses their application to Constellation projects, and addresses the plans for the coming year.

  12. Radiation Modification of Natural Polysaccharides for Application in Agriculture

    International Nuclear Information System (INIS)

    AbdEl-Rehim, Hassan A.; Hegazy, El-Sayed A.; El-Barbary, Ahmed M.

    2010-01-01

    Controlling the degradation process of natural polymer like chitosan by gamma ray from a 60 Co source at different doses in, powder form, and in presence of additives was investigated. The efficiency of these methods were verified by viscometric and GPC analysis through determination the average molecular weights of degraded natural polymers. The chemical-irradiation degradation method was much more appropriate from economical point of view. Characterization of degraded polymer by FTIR spectroscopy, UV-Vis spectroscopy, XRD, ESR and TGA analysis were done. The degraded sodium alginate with different doses were used for wheat plant. It was observed that spraying treated plants with alginate solutions improved plant growth and increasing its yields. Significant changes in amino acids content of the plants was observed as a result of treating them with irradiated alginate solutions. Irradiated Na alginate induced changes in plant DNA, which may be appear as increase in growth and yield characters. The degraded natural polymer chitosans were also tested as growth promoters for some plants like Zea maize and bean plant . It was found that the degraded chitosan has a great effect on the productivity and properties of these plants. Antiviral activity of irradiated alginate against plant infection by tobacco mosaic virus was investigated. It is clear that the relatively high Molecular weigh alginate inhibits and reduces the plant infection . The effects of chitosan oligomers on gray mould caused by Botrytis cinerea in tomato plants was investigated. It was found that degraded chitosan controlled the gray mould disease caused by B. cinerea compared with control. (author)

  13. Probability of Causation for Space Radiation Carcinogenesis Following International Space Station, Near Earth Asteroid, and Mars Missions

    Science.gov (United States)

    Cucinotta, Francis A.; Kim, Myung-Hee Y.; Chappell, Lori J.

    2012-01-01

    Cancer risk is an important concern for International Space Station (ISS) missions and future exploration missions. An important question concerns the likelihood of a causal association between a crew members radiation exposure and the occurrence of cancer. The probability of causation (PC), also denoted as attributable risk, is used to make such an estimate. This report summarizes the NASA model of space radiation cancer risks and uncertainties, including improvements to represent uncertainties in tissue-specific cancer incidence models for never-smokers and the U.S. average population. We report on tissue-specific cancer incidence estimates and PC for different post-mission times for ISS and exploration missions. An important conclusion from our analysis is that the NASA policy to limit the risk of exposure-induced death to 3% at the 95% confidence level largely ensures that estimates of the PC for most cancer types would not reach a level of significance. Reducing uncertainties through radiobiological research remains the most efficient method to extend mission length and establish effective mitigators for cancer risks. Efforts to establish biomarkers of space radiation-induced tumors and to estimate PC for rarer tumor types are briefly discussed.

  14. Nature's Way of Making Audacious Space Projects Viable

    Science.gov (United States)

    Metzger, Philip T.

    2011-01-01

    Building a starship within the next 100 years is an audacious goal. To be successful, we need sustained funding that may be difficult to maintain in the face of economic challenges that are poised to arise during these next 100 years. Our species' civilization has only recently reached the classification as (approximately) Type-I on the Kardashev scale; that is, we have spread out from one small locality to become a global species mastering the energy and resources of an entire planet. In the process we discovered the profound truth that the two-dimensional surface of our world is not flat, but has positive curvature and is closed so that its area and resources are finite. It should come as no surprise to a Type I civilization when its planet's resources dWindle; how could they not? Yet we have gone year by year, government by government, making little investment for the time when civilization becomes violent in the unwelcome contractions that must follow, when we are forced too late into the inevitable choice: to remain and diminish on an unhappy world; or to expand into the only dimension remaining perpendicularly outward from the surface into space. Then some day we may become a Type-II civilization, mastering the resources of an entire solar system. Our species cannot continue as we have on this planet for another 100 years. Doubtless it falls on us today, the very time we intended to start building a starship, to make the late choice. We wished this century to be filled with enlightenment and adventure; it could be an age of desperation and war. What a time to begin an audacious project in space! How will we maintain consistent funding for the next 100 years? Fortunately, saving a civilization, mastering a solar system, and doing other great things like building starships amount to mostly the same set of tasks. Recognizing what we must be about during the next 100 years will make it possible to do them all.

  15. Extractable protein of radiation vulcanized natural rubber latex

    International Nuclear Information System (INIS)

    Soebianto, Y.S.; Ratnayake, U.M.; Makuuchi, Keizo; Yoshii, Fumio; Kume, Tamikazu

    2000-01-01

    Protein remained in the latex products are reported to cause serious allergy. A new method to reduce the protein level in the latex products by irradiation is reported. Water soluble protein (WSP) solution (10%) was added into radiation vulcanized NR latex (RVNRL) in three different processes. The amount of WSP was 3 phr. It was only added to RVNRL (standard), added to re-centrifuged RVNRL (pre-centrifugation), and added to RVNRL followed by centrifugation (post-centrifugation). The protein content was determined by enhanced BCA method, and identified by SDS-PAGE. Extractable protein (EP) from the rubber has been reduced up to the minimum protein detection by combining WSP addition and centrifugation. Short leaching time (20-30 min.) can be achieved after the combine treatment, and SDS-PAGE confirms the reduction of soluble protein in the serum phase, and disappearance of protein bands in the rubber extract. Protein-WSP interaction produces water soluble complex, and removed by centrifugation. The efficiency of protein removal by WSP depends on its molecular weight of WSP which relates to its water solubility. (author)

  16. Cost evaluation of radiation vulcanization of natural rubber latex

    International Nuclear Information System (INIS)

    Makuuchi, K.

    2003-01-01

    Cost of radiation vulcanized NR latex was evaluated. The plant would be built in an existing dipping factory in an industrial area in a Southeast Asian country. One thousands dry tons of NR latex are vulcanized with a low energy electron accelerator. The electron accelerator is a self-shielding low energy type. The maximum accelerating voltage is 300 kV and the output power is 10 kW. The total construction cost of the plant is $400,000 including electron accelerator and other equipments. Costs of raw materials and utilities are $1.165 and $0.023 per one kg of product, respectively. The fixed costs of the plant consist of labor costs, labor overhead, maintenance, plant overhead, depreciation, and bank interest. It is $0.190/kg of product. The company overhead for operation including company management, R and D and insurance is $0.044/kg of product. Thus, the total production cost is estimated to be $1.422/kg of product. (author)

  17. Calibration of TEPC for CubeSat Experiment to Measure Space Radiation

    Directory of Open Access Journals (Sweden)

    Uk-Won Nam

    2015-06-01

    Full Text Available A newly designed Tissue Equivalent Proportional Counter (TEPC has been developed for the CubeSat mission, SIGMA (Scientific cubesat with Instruments for Global Magnetic field and rAdiation to investigate space radiation. In order to test the performance of the TEPC, we have performed heavy ion beam experiments with the Heavy Ion Medical Accelerator in Chiba (HIMAC, Japan. In space, human cells can be exposed to complex radiation sources, such as X-ray, Gamma ray, energetic electrons, protons, neutrons and heavy charged particles in a huge range of energies. These generate much a larger range of Linear Energy Transfer (LET than on the ground and cause unexpected effects on human cells. In order to measure a large range of LET, from 0.3 to 1,000 keV/μm, we developed a compact TEPC which measures ionized particles produced by collisions between radiation sources and tissue equivalent materials in the detector. By measuring LET spectra, we can easily derive the equivalent dose from the complicated space radiation field. In this HIMAC experiment, we successfully obtained the linearity response for the TEPC with Fe 500 MeV/u and C 290 MeV/u beams and demonstrated the performance of the active radiation detector.

  18. Of Modeling the Radiation Hazards Along Trajectory Space Vehicles Various Purpose

    Science.gov (United States)

    Grichshenko, Valentina

    2016-07-01

    The paper discusses the results of the simulation of radiation hazard along trajectory low-orbit spacecraft for various purposes, geostationary and navigation satellites. Developed criteria of reliability of memory cells in Space, including influence of cosmic rays (CR), differences of geophysical and geomagnetic situation on SV orbit are discussed. Numerical value of vertical geomagnetic stiffness, of CR flux and assessment of correlation failures of memory cells along low-orbit spacecrafts trajectory are presented. Obtained results are used to forecasting the radiation situation along SV orbit, reliability of memory cells in the Space and to optimize nominal equipment kit and payload of Kazakhstan SV.

  19. Estimating the Global Agricultural Impact of Solar Radiation Management using Volcanic Eruptions as Natural Experiments

    Science.gov (United States)

    Proctor, J.; Hsiang, S. M.; Burney, J. A.; Burke, M.; Schlenker, W.

    2017-12-01

    Solar radiation management (SRM) is increasingly considered an option for managing global temperatures, yet the economic impacts of ameliorating climatic changes by scattering sunlight back to space remain largely unknown. Though SRM may increase crop yields by reducing heat stress, its impacts from concomitant changes in available sunlight have never been empirically estimated. Here we use the volcanic eruptions that inspired modern SRM proposals as natural experiments to provide the first estimates of how the stratospheric sulfate aerosols (SS) created by the eruptions of El Chichon and Pinatubo altered the quantity and quality of global sunlight, how those changes in sunlight impacted global crop yields, and the total effect that SS may have on yields in an SRM scenario when the climatic and sunlight effects are jointly considered. We find that the sunlight-mediated impact of SS on yields is negative for both C4 (maize) and C3 (soy, rice, wheat) crops. Applying our yield model to a geoengineering scenario using SS-based SRM from 2050-2069, we find that SRM damages due to scattering sunlight are roughly equal in magnitude to SRM benefits from cooling. This suggests that SRM - if deployed using SS similar to those emitted by the volcanic eruptions it seeks to mimic - would attenuate little of the damages from climate change to global agriculture on net. Our approach could be extended to study SRM impacts on other global systems, such as human health or ecosystem function.

  20. p53-dependent adaptive responses in human cells exposed to space radiations.

    Science.gov (United States)

    Takahashi, Akihisa; Su, Xiaoming; Suzuki, Hiromi; Omori, Katsunori; Seki, Masaya; Hashizume, Toko; Shimazu, Toru; Ishioka, Noriaki; Iwasaki, Toshiyasu; Ohnishi, Takeo

    2010-11-15

    It has been reported that priming irradiation or conditioning irradiation with a low dose of X-rays in the range of 0.02-0.1 Gy induces a p53-dependent adaptive response in mammalian cells. The aim of the present study was to clarify the effect of space radiations on the adaptive response. Two human lymphoblastoid cell lines were used; one cell line bears a wild-type p53 (wtp53) gene, and another cell line bears a mutated p53 (mp53) gene. The cells were frozen during transportation on the space shuttle and while in orbit in the International Space Station freezer for 133 days between November 15, 2008 and March 29, 2009. After the frozen samples were returned to Earth, the cells were cultured for 6 h and then exposed to a challenging X-ray-irradiation (2 Gy). Cellular sensitivity, apoptosis, and chromosome aberrations were scored using dye-exclusion assays, Hoechst33342 staining assays, and chromosomal banding techniques, respectively. In cells exposed to space radiations, adaptive responses such as the induction of radioresistance and the depression of radiation-induced apoptosis and chromosome aberrations were observed in wtp53 cells but not in mp53 cells. These results have confirmed the hypothesis that p53-dependent adaptive responses are apparently induced by space radiations within a specific range of low doses. The cells exhibited this effect owing to space radiations exposure, even though the doses in space were very low. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Molecular pathway activation in cancer and tissue following space radiation exposure

    Science.gov (United States)

    Kovyrshina, Tatiana A.

    Space radiation exposure is an important safety concern for astronauts, especially since one of the risks is carcinogenesis. This thesis explores the link between lung, colorectal, and breast cancer and iron particles and gamma radiation on a molecular level. We obtained DNA microarrays for each condition from the Gene Expression Omnibus (GEO), a public functional genomics data repository, cleaned up the data, and analysed overexpression and underexpression of pathway analysis. Our results show that pathways which participate in DNA replication appear to be overexpressed in cancer cells and cells exposed to ionizing radiation.

  2. A COTS-based single board radiation-hardened computer for space applications

    International Nuclear Information System (INIS)

    Stewart, S.; Hillman, R.; Layton, P.; Krawzsenek, D.

    1999-01-01

    There is great community interest in the ability to use COTS (Commercial-Off-The-Shelf) technology in radiation environments. Space Electronics, Inc. has developed a high performance COTS-based radiation hardened computer. COTS approaches were selected for both hardware and software. Through parts testing, selection and packaging, all requirements have been met without parts or process development. Reliability, total ionizing dose and single event performance are attractive. The characteristics, performance and radiation resistance of the single board computer will be presented. (authors)

  3. The space-time outside a source of gravitational radiation: the axially symmetric null fluid

    Energy Technology Data Exchange (ETDEWEB)

    Herrera, L. [Universidad Central de Venezuela, Escuela de Fisica, Facultad de Ciencias, Caracas (Venezuela, Bolivarian Republic of); Universidad de Salamanca, Instituto Universitario de Fisica Fundamental y Matematicas, Salamanca (Spain); Di Prisco, A. [Universidad Central de Venezuela, Escuela de Fisica, Facultad de Ciencias, Caracas (Venezuela, Bolivarian Republic of); Ospino, J. [Universidad de Salamanca, Departamento de Matematica Aplicada and Instituto Universitario de Fisica Fundamental y Matematicas, Salamanca (Spain)

    2016-11-15

    We carry out a study of the exterior of an axially and reflection symmetric source of gravitational radiation. The exterior of such a source is filled with a null fluid produced by the dissipative processes inherent to the emission of gravitational radiation, thereby representing a generalization of the Vaidya metric for axially and reflection symmetric space-times. The role of the vorticity, and its relationship with the presence of gravitational radiation is put in evidence. The spherically symmetric case (Vaidya) is, asymptotically, recovered within the context of the 1 + 3 formalism. (orig.)

  4. Investigation of space radiation effects in polymeric film-forming materials

    Science.gov (United States)

    Giori, C.; Yamauchi, T.; Jarke, F.

    1975-01-01

    The literature search in the field of ultraviolet radiation effects that was conducted during the previous program, Contract No. NAS1-12549, has been expanded to include the effects of charged particle radiation and high energy electromagnetic radiation. The literature from 1958 to 1969 was searched manually, while the literature from 1969 to present was searched by using a computerized keyword system. The information generated from this search was utilized for the design of an experimental program aimed at the development of materials with improved resistance to the vacuum-radiation environment of space. Preliminary irradiation experiments were performed which indicate that the approaches and criteria employed are very promising and may provide a solution to the challenging problem of polymer stability to combined ultraviolet/high energy radiation.

  5. Geographically determined dependencies in the value of the constant natural radiation gamma-background

    International Nuclear Information System (INIS)

    Miloslavov, V.

    2001-01-01

    The problem of the assessment of the influence of natural gamma background changes on the population is discussed. It is considered that the populations in different geographic regions have adapted by evolution mechanisms to the respective unchanged (without human activities) radiation background. The background limits for each area form the 'radiation comfortable zone' which varies very much for the different geographic areas. Leaving the 'comfortable zone' leads to a triggering of adaptive mechanisms in the population including the natural selection in order to reach an equilibrium. Thus, the radiation impact exceeding the 'comfortable zone' is expected to cause harm for a part of the population which is preliminarily burden or uncapable to adapt. From this point of view the increased morbidity due to radiation factor in those cases remains hidden. As a conclusion it is pointed out that the proposed increase of the annual dose for the population might result with harmful consequences for the whole human population

  6. Space radiation-induced bystander effect: kinetics of biologic responses, mechanisms, and significance of secondary radiations

    International Nuclear Information System (INIS)

    Gonon, Geraldine

    2011-01-01

    Widespread evidence indicates that exposure of cell cultures to a particles results in significant biological changes in both the irradiated and non-irradiated bystander cells in the population. The induction of non-targeted biological responses in cell cultures exposed to low fluences of high charge (Z) and high energy (E) particles is relevant to estimates of the health risks of space radiation and to radiotherapy. Here, we investigated the mechanisms underlying the induction of stressful effects in confluent normal human fibroblast cultures exposed to low fluences of 1000 MeV/u iron ions (linear energy transfer (LET) 151 keV/μm), 600 MeV/u silicon ions (LET 50 keV/μm) or 290 MeV/u carbon ions (LET 13 keV/μm). We compared the results with those obtained in cell cultures exposed, in parallel, to low fluences of 0.92 MeV/u a particles (LET 109 keV/μm). Induction of DNA damage, changes in gene expression, protein carbonylation and lipid peroxidation during 24 h after exposure of confluent cultures to mean doses as low as 0.2 cGy of iron or silicon ions strongly supported the propagation of stressful effects from irradiated to bystander cells. At a mean dose of 0.2 cGy, only 1 and 3 % of the cells would be targeted through the nucleus by an iron or silicon ion, respectively. Within 24 h post-irradiation, immunoblot analyses revealed significant increases in the levels of phospho-TP53 (serine 15), p21Waf1 (also known as CDKN1A), HDM2, phospho-ERK1/2, protein carbonylation and lipid peroxidation. The magnitude of the responses suggested participation of non-targeted cells in the response. Furthermore, when the irradiated cell populations were subcultured in fresh medium shortly after irradiation, greater than expected increases in the levels of these markers were also observed during 24 h. Together, the results imply a rapidly propagated and persistent bystander effect. In situ analyses in confluent cultures showed 53BP1 foci formation, a marker of DNA damage, in

  7. OLTARIS: An Efficient Web-Based Tool for Analyzing Materials Exposed to Space Radiation

    Science.gov (United States)

    Slaba, Tony; McMullen, Amelia M.; Thibeault, Sheila A.; Sandridge, Chris A.; Clowdsley, Martha S.; Blatting, Steve R.

    2011-01-01

    The near-Earth space radiation environment includes energetic galactic cosmic rays (GCR), high intensity proton and electron belts, and the potential for solar particle events (SPE). These sources may penetrate shielding materials and deposit significant energy in sensitive electronic devices on board spacecraft and satellites. Material and design optimization methods may be used to reduce the exposure and extend the operational lifetime of individual components and systems. Since laboratory experiments are expensive and may not cover the range of particles and energies relevant for space applications, such optimization may be done computationally with efficient algorithms that include the various constraints placed on the component, system, or mission. In the present work, the web-based tool OLTARIS (On-Line Tool for the Assessment of Radiation in Space) is presented, and the applicability of the tool for rapidly analyzing exposure levels within either complicated shielding geometries or user-defined material slabs exposed to space radiation is demonstrated. An example approach for material optimization is also presented. Slabs of various advanced multifunctional materials are defined and exposed to several space radiation environments. The materials and thicknesses defining each layer in the slab are then systematically adjusted to arrive at an optimal slab configuration.

  8. Radiation Measurements Performed with Active Detectors Relevant for Human Space Exploration.

    Science.gov (United States)

    Narici, Livio; Berger, Thomas; Matthiä, Daniel; Reitz, Günther

    2015-01-01

    A reliable radiation risk assessment in space is a mandatory step for the development of countermeasures and long-duration mission planning in human spaceflight. Research in radiobiology provides information about possible risks linked to radiation. In addition, for a meaningful risk evaluation, the radiation exposure has to be assessed to a sufficient level of accuracy. Consequently, both the radiation models predicting the risks and the measurements used to validate such models must have an equivalent precision. Corresponding measurements can be performed both with passive and active devices. The former is easier to handle, cheaper, lighter, and smaller but they measure neither the time dependence of the radiation environment nor some of the details useful for a comprehensive radiation risk assessment. Active detectors provide most of these details and have been extensively used in the International Space Station. To easily access such an amount of data, a single point access is becoming essential. This review presents an ongoing work on the development of a tool that allows obtaining information about all relevant measurements performed with active detectors providing reliable inputs for radiation model validation.

  9. A metabolomics guided exploration of marine natural product chemical space.

    Science.gov (United States)

    Floros, Dimitrios J; Jensen, Paul R; Dorrestein, Pieter C; Koyama, Nobuhiro

    2016-09-01

    Natural products from culture collections have enormous impact in advancing discovery programs for metabolites of biotechnological importance. These discovery efforts rely on the metabolomic characterization of strain collections. Many emerging approaches compare metabolomic profiles of such collections, but few enable the analysis and prioritization of thousands of samples from diverse organisms while delivering chemistry specific read outs. In this work we utilize untargeted LC-MS/MS based metabolomics together with molecular networking to. This approach annotated 76 molecular families (a spectral match rate of 28 %), including clinically and biotechnologically important molecules such as valinomycin, actinomycin D, and desferrioxamine E. Targeting a molecular family produced primarily by one microorganism led to the isolation and structure elucidation of two new molecules designated maridric acids A and B. Molecular networking guided exploration of large culture collections allows for rapid dereplication of know molecules and can highlight producers of uniques metabolites. These methods, together with large culture collections and growing databases, allow for data driven strain prioritization with a focus on novel chemistries.

  10. Radiation hardening of optical fibers and fiber sensors for space applications: recent advances

    Science.gov (United States)

    Girard, S.; Ouerdane, Y.; Pinsard, E.; Laurent, A.; Ladaci, A.; Robin, T.; Cadier, B.; Mescia, L.; Boukenter, A.

    2017-11-01

    In these ICSO proceedings, we review recent advances from our group concerning the radiation hardening of optical fiber and fiber-based sensors for space applications and compare their benefits to state-of-the-art results. We focus on the various approaches we developed to enhance the radiation tolerance of two classes of optical fibers doped with rare-earths: the erbium (Er)-doped ones and the ytterbium/erbium (Er/Yb)-doped ones. As a first approach, we work at the component level, optimizing the fiber structure and composition to reduce their intrinsically high radiation sensitivities. For the Erbium-doped fibers, this has been achieved using a new structure for the fiber that is called Hole-Assisted Carbon Coated (HACC) optical fibers whereas for the Er/Ybdoped optical fibers, their hardening was successfully achieved adding to the fiber, the Cerium element, that prevents the formation of the radiation-induced point defects responsible for the radiation induced attenuation in the infrared part of the spectrum. These fibers are used as part of more complex systems like amplifiers (Erbium-doped Fiber Amplifier, EDFA or Yb-EDFA) or source (Erbium-doped Fiber Source, EDFS or Yb- EDFS), we discuss the impact of using radiation-hardened fibers on the system radiation vulnerability and demonstrate the resistance of these systems to radiation constraints associated with today and future space missions. Finally, we will discuss another radiation hardening approach build in our group and based on a hardening-by-system strategy in which the amplifier is optimized during its elaboration for its future mission considering the radiation effects and not in-lab.

  11. TLD survey of natural radiation environment along the south-west coast of India

    International Nuclear Information System (INIS)

    Sunta, C.M.; David, M.; Subbaratnam, T.

    1980-01-01

    An extensive population and house dosimetry programme using thermoluminescence dosimetry was carried out in the areas of high level natural background radiation (due to monazite deposits) in Kerala during 1968-70. Further surveys were carried out in the areas not covered under the above-mentioned programme and the results are presented. The radiation exposure from external sources only is measured. (M.G.B.)

  12. Radiation damage in natural and synthetic halite. Progress report January 1992 - February 1993

    International Nuclear Information System (INIS)

    Garcia Celma, A.

    1993-12-01

    This report complements the information presented in the report of December 1992 regarding the research performed at the ECN on radiation damage in salt. It consists of two parts. The first part regards the amount of stored energy which can be developed by gamma-irradiation on different types of halite and considers both the effect of low dose rates in developing radiation damage, and the possible saturation level of radiation damage in natural halite. The second part presents a model to simulate radiation damage development which incorporates some extensions in the Jain-Lidiard model. Due to malfunction of the Small Angle Neutron Scattering installation, neither the previously reported results nor the newly obtained can be trusted and therefore are not reported here. These results regard the shape, size and size distribution of radiation damage defects. (orig.)

  13. Space radiation evaluation of 16Mbit DRAMs for mass memory applications

    International Nuclear Information System (INIS)

    Calvel, P.; Lamothe, P.; Barillot, C.; Ecoffet, R.; Duzellier, S.; Stassinopoulos, E.G.

    1994-01-01

    In the frame of Mass Memory Applications for space missions, 16 Mbit DRAM from IBM and TEXAS INSTRUMENTS have been evaluated to space radiation, by the CECIL heavy ions testing coordination group. This paper presents heavy ions, protons and total dose data results for 16 Mbit DRAMs from IBM and TEXAS INSTRUMENTS, including a 'built-in ECC' DRAM. Single Event Phenomena rate are calculated for low earth orbits

  14. Influence of emulsion nature on radiation response of β-carotene in an aqueous medium

    International Nuclear Information System (INIS)

    Bhushan, B.; Tobback, P.; Snauwaert, F.; Maes, E.

    1978-01-01

    The radiation response of β-carotene was followed in lipid solvents and in aqueous preparations. The nature of the solvent was found to have a marked influence on the response of β-carotene to γ-radiation. In aqueous emulsions radiation destruction of β-carotene was far less than that observed in solutions. Oil in water (O/W) emulsions of petroleum ether offered maximum protection to β-carotene against radiation damage. This observation was attributed to the multiphase nature of the emulsion since a transparent aqueous preparation was observed to offer no protection upon irradiation. Solubility of crystalline β-carotene in water was found to increase with the emulsifier concentration. Irradiation revealed that the extent of β-carotene destruction was dose dependent and increased with the solubility of β-carotene in water. In the presence of a free radical scavenger DPPH β-carotene exhibited varied radiation response depending upon the nature of solvents used. Thus, in transparent aqueous preparations the protection afforded by added DPPH to β-carotene was almost complete, while its influence was insignificant in O/W emulsions. The significance of these observations in radiation processing of foods is discussed. (author)

  15. Improved Understanding of Space Radiation Effects on Exploration Electronics by Advanced Modeling of Nanoscale Devices and Novel Materials, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Future NASA space exploration missions will use nanometer-scale electronic technologies which call for a shift in how radiation effects in such devices and materials...

  16. Performances of ionizing radiation detectors required as part of a space weather service system

    Science.gov (United States)

    Cyamukungu, Mathias; Benck, Sylvie

    2012-07-01

    The selection of space radiation monitoring instruments is an essential phase in the planning of a space science mission, specifically when the data are acquired for use in the frame of a space weather service. Customer requirements for space weather services have been expressed by users and collected in reference documents like the ESA's "SSA Space Weather Segment Customer Requirement Document", among others. A review of these requirements and their implications for measurements at LEO, HEO, GTO, MEO and GEO will be presented enriched with thoroughly derived priority ranks associated with each measurable parameter. Then, the authors will describe a Global Performance Index (GPI) on various orbits for more than a dozen of currently developed or existing instruments, to conclude on an optimal selection of instruments that would be suitable to acquire the highest quality data usable for space weather applications.

  17. Space situational awareness satellites and ground based radiation counting and imaging detector technology

    Energy Technology Data Exchange (ETDEWEB)

    Jansen, Frank, E-mail: frank.jansen@dlr.de [DLR Institute of Space Systems, Robert-Hooke-Str. 7, 28359 Bremen (Germany); Behrens, Joerg [DLR Institute of Space Systems, Robert-Hooke-Str. 7, 28359 Bremen (Germany); Pospisil, Stanislav [Czech Technical University, IEAP, 12800 Prague 2, Horska 3a/22 (Czech Republic); Kudela, Karel [Slovak Academy of Sciences, IEP, 04001 Kosice, Watsonova 47 (Slovakia)

    2011-05-15

    We review the current status from the scientific and technological point of view of solar energetic particles, solar and galactic cosmic ray measurements as well as high energy UV-, X- and gamma-ray imaging of the Sun. These particles and electromagnetic data are an important tool for space situational awareness (SSA) aspects like space weather storm predictions to avoid failures in space, air and ground based technological systems. Real time data acquisition, position and energy sensitive imaging are demanded by the international space weather forecast services. We present how newly developed, highly miniaturized radiation detectors can find application in space in view of future SSA related satellites as a novel space application due to their counting and imaging capabilities.

  18. Annual Conference on Nuclear and Space Radiation Effects, 21st, Colorado Springs, CO, July 23-25, 1984, Proceedings

    Science.gov (United States)

    Winokur, P. S. (Editor)

    1984-01-01

    Radiation effects on electronic systems and devices (particularly spacecraft systems) are examined with attention given to such topics as radiation transport, energy deposition, and charge collection; single-event phenomena; basic mechanisms of radiation effects in structures and materials; and EMP phenomena. Also considered are radiation effects in integrated circuits, spacecraft charging and space radiation effects, hardness assurance for devices and systems, and SGEMP/IEMP phenomena.

  19. Natural antioxidants for protection and radiation effects treatment

    International Nuclear Information System (INIS)

    Kafafi, Y.A.

    2010-01-01

    Since many degenerative human diseases have been recognized as being a consequence of free radical damage, there have been many studies undertaken on how to delay or prevent the onset of these diseases. The most likely and practical way to fight against degenerative diseases is to improve body antioxidant status which could be achieved by higher consumption of vegetables and fruits. Foods from plant origin usually contain natural antioxidants that can scavenge free radicals. It is clear that vitamin C and antioxidant capacity are not directly related and thus that vitamin C is not the only antioxidant in juices with high content of vitamin C. Antioxidant capacity may also arise from phenolics / flavonoids found in plants. Three major antioxidant nutrients are vitamin C, vitamin E and beta carotene. Intake of these nutrients has an inverse relationship with degenerative disease risk. In an elderly study, it was found that high consumption of flavonoids correlated with low risk of coronary heart disease. Some evidence showed that flavonoids could protect membrane lipid from oxidation. A major source of flavonoids are vegetables and fruits. (author)

  20. Radioactivity levels in Indian coal and some technologically enhanced exposure to natural radiation environment of India

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Mishra, U.C.

    1988-01-01

    The summary of results of gamma-spectrometric measurements of natural radioactivity levels in coal from mines, coal, fly-ash, slag and soil samples from thermal power plants in India are presented. These constitute the sources of technologic ally enhanced exposures to natural radiation. Brief description of sampling and measurement procedure is given. Radiation dose to the population from coal fired power plants for electricity generation have been calculated using the model developed by UNSCEAR and ORNL reports with correction for local population density. (author). 13 refs., 7 tabs., 8 figs

  1. Space radiation dose analysis for solar flare of August 1989

    International Nuclear Information System (INIS)

    Nealy, J.E.; Simonsen, L.C.; Sauer, H.H.; Wilson, J.W.; Townsend, L.W.

    1990-12-01

    Potential dose and dose rate levels to astronauts in deep space are predicted for the solar flare event which occurred during the week of August 13, 1989. The Geostationary Operational Environmental Satellite (GOES-7) monitored the temporal development and energy characteristics of the protons emitted during this event. From these data, differential fluence as a function of energy was obtained in order to analyze the flare using the Langley baryon transport code, BRYNTRN, which describes the interactions of incident protons in matter. Dose equivalent estimates for the skin, ocular lens, and vital organs for 0.5 to 20 g/sq cm of aluminum shielding were predicted. For relatively light shielding (less than 2 g/sq cm), the skin and ocular lens 30-day exposure limits are exceeded within several hours of flare onset. The vital organ (5 cm depth) dose equivalent is exceeded only for the thinnest shield (0.5 g/sq cm). Dose rates (rem/hr) for the skin, ocular lens, and vital organs are also computed

  2. Modern state of the application of ionizing radiation for protection of environment. 1. Ionizing radiation sources. Purification of natural and drinking water (review)

    International Nuclear Information System (INIS)

    Pikaev, AK.

    2000-01-01

    Review of modern state of the application of ionizing radiations for protection of environment and natural and drinking water purification is presented. Building of installations with electron accelerators with summarized power of beam ∼0.6 MW signifies that application of ionizing radiation for ecological needs increase. It is pointed out that extensible application of electron accelerators is explained by their safety and efficiency as compared with gamma-sources. New information about ionizing radiation sources, radiation-chemical purification of polluted natural and drinking water, mechanisms of processes taking place during treatment by ionizing radiations are generalized [ru

  3. Concepts and challenges in cancer risk prediction for the space radiation environment

    Science.gov (United States)

    Barcellos-Hoff, Mary Helen; Blakely, Eleanor A.; Burma, Sandeep; Fornace, Albert J.; Gerson, Stanton; Hlatky, Lynn; Kirsch, David G.; Luderer, Ulrike; Shay, Jerry; Wang, Ya; Weil, Michael M.

    2015-07-01

    Cancer is an important long-term risk for astronauts exposed to protons and high-energy charged particles during travel and residence on asteroids, the moon, and other planets. NASA's Biomedical Critical Path Roadmap defines the carcinogenic risks of radiation exposure as one of four type I risks. A type I risk represents a demonstrated, serious problem with no countermeasure concepts, and may be a potential "show-stopper" for long duration spaceflight. Estimating the carcinogenic risks for humans who will be exposed to heavy ions during deep space exploration has very large uncertainties at present. There are no human data that address risk from extended exposure to complex radiation fields. The overarching goal in this area to improve risk modeling is to provide biological insight and mechanistic analysis of radiation quality effects on carcinogenesis. Understanding mechanisms will provide routes to modeling and predicting risk and designing countermeasures. This white paper reviews broad issues related to experimental models and concepts in space radiation carcinogenesis as well as the current state of the field to place into context recent findings and concepts derived from the NASA Space Radiation Program.

  4. 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.

  5. 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.

  6. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  7. Radiation monitoring of soil cover of natural uranium in the Issyk-Kul province

    International Nuclear Information System (INIS)

    Djenbaev, B.M.; Toktoeva, T.E.; Kaldibaev, B.K.; Zholbolduev, B.T.

    2015-01-01

    This article presents the current state in the radioecological soil Issyk-Kul province of natural uranium. Found that the background radiation - exposure dose and artificial radionuclides in the soil of the coastal zone of the lake as a whole at the level of the background and the acceptance of lower standards except for natural technogenic and some natural areas. Radioecological this province is mild natural and industrial uranium province.We have previously established 10 experimental plots around Issyk-Kul and the measurement showed that the power of natural background radiation in the gamma radiation of the coastal lake zone is an average of 17 to 25 mR/h in some areas up to 40 mR/h. As the distance from the lake to the side slopes of its level in some places rises to 40 mR/h, especially in some mountainous areas, canyons, which are based on the rocks, granites and their fragments are small, red sand, with a slightly increased radioactivity. For small areas with high natural background radiation can be attributed to the beaches of the coastal zone v. Jenish, v. Ak-Terek, located on the southern shore of Issyk-Kul Lake. The radioactivity of 30 - 60 mR/h, and in areas with a high content of iron in the sand inclusions level exposure dose increases up to 400 mR/h. Small areas of the coastal zone of Issyk-Kul Lake, mostly mud deposits with characteristic brilliance giving high radiation background. These areas include: the beach v.Tosor - 40-50 mR/h, 10 km west of the coast v.Kaji-Sai - 32-40 mR/h, the shore around with. Toru-Aigyr - 30 mR/h, the coast around v.Tamchi - 40-50 mR/h. In general, cities in the Issyk-Kul basin Kara-Kol, Cholpon-Ata and Balykchy radiation situation quite well, the average exposure dose of gamma radiation does not exceed 20 - 22 mR/h, but in some places the use of crushed granite, as filler and construction material, the level of background radiation increases to 40-50 mR/h This indicates that these natural resources, without first

  8. Proceedings of the 3rd international workshop on radiation effects on semiconductor devices for space application

    International Nuclear Information System (INIS)

    1998-10-01

    This publication is the collection of the paper presented at the title workshop. The main purpose of the workshop is to bring the chance for exchange of information between scientists and engineers who work in the field of research and development of semiconductor devices used in strong radiation environment in space. The 27 of the presented papers are indexed individually. (J.P.N.)

  9. Animal studies of life shortening and cancer risk from space radiation

    Science.gov (United States)

    Wood, D. H.; Yochmowitz, M. G.; Hardy, K. A.; Salmon, Y. L.

    The U. S. Air Force study of the delayed effects of single, total body exposures to simulated space radiation in rhesus monkeys is now in its 21st year. Observations on 301 irradiated and 57 age-matched control animals indicate that life expectancy loss from exposure to protons in the energy range encountered in the Van Allen belts and solar proton events can be expressed as a logarithmic function of the dose. The primary causes of life shortening are cancer and endometriosis (an abnormal proliferation of the lining of the uterus in females). Life shortening estimates permit comparison of the risk associated with space radiation exposures to be compared with that of other occupational and environmental hazards, thereby facilitating risk/benefit decisions in the planning and operational phases of manned space missions. Calculations of the relative risk of fatal cancers in the irradiated subjects reveal that the total body surface dose required to double the risk of death from cancer over a 20-year post exposure period varies with the linear energy transfer (LET) of the radiation. The ability to determine the integrated dose and LET spectrum in space radiation exposures of human is, therefore, critical to the assessment of life-time cancer risk.

  10. Comparison of the ionizing radiation effects on cochineal, annatto and turmeric natural dyes

    International Nuclear Information System (INIS)

    Cosentino, Helio M.; Takinami, Patricia Y.I.; Mastro, Nelida L. del

    2016-01-01

    As studies on radiation stability of food dyes are scarce, commercially important natural food grade dyes were evaluated in terms of their sensitivity against gamma ionizing radiation. Cochineal, annatto and turmeric dyes with suitable concentrations were subjected to increasing doses up to 32 kGy and analyzed by spectrophotometry and capillary electrophoresis. The results showed different pattern of absorbance versus absorbed dose for the three systems. Carmine, the glucosidal coloring matter from the scale insect Coccus cacti L., Homoptera (cochineal) remained almost unaffected by radiation up to doses of about 32 kGy (absorbance at 494 nm). Meanwhile, at that dose, a plant-derived product annatto or urucum (Bixa orellana L.) tincture presented a nearly 58% reduction in color intensity. Tincture of curcumin (diferuloylmethane) the active ingredient in the eastern spice turmeric (Curcuma longa) showed to be highly sensitive to radiation when diluted. These data shall be taken in account whenever food products containing these food colors were going to undergo radiation processing. - Highlights: • Comparison of radiosensitivity of food colors was performed. • Carmine showed the highest resistance to radiation. • Annatto and turmeric behaved sensitive to radiation when diluted. • Turmeric was the most affected by ionizing radiation.

  11. Exploring innovative radiation shielding approaches in space: A material and design study for a wearable radiation protection spacesuit.

    Science.gov (United States)

    Vuolo, M; Baiocco, G; Barbieri, S; Bocchini, L; Giraudo, M; Gheysens, T; Lobascio, C; Ottolenghi, A

    2017-11-01

    We present a design study for a wearable radiation-shielding spacesuit, designed to protect astronauts' most radiosensitive organs. The suit could be used in an emergency, to perform necessary interventions outside a radiation shelter in the space habitat in case of a Solar Proton Event (SPE). A wearable shielding system of the kind we propose has the potential to prevent the onset of acute radiation effects in this scenario. In this work, selection of materials for the spacesuit elements is performed based on the results of dedicated GRAS/Geant4 1-dimensional Monte Carlo simulations, and after a trade-off analysis between shielding performance and availability of resources in the space habitat. Water is the first choice material, but also organic compounds compatible with a human space habitat are considered (such as fatty acids, gels and liquid organic wastes). Different designs and material combinations are proposed for the spacesuits. To quantify shielding performance we use GRAS/Geant4 simulations of an anthropomorphic phantom in an average SPE environment, with and without the spacesuit, and we compare results for the dose to Blood Forming Organs (BFO) in Gy-Eq, i.e. physical absorbed dose multiplied by the proton Relative Biological Effectiveness (RBE) for non-cancer effects. In case of SPE occurrence for Intra-Vehicular Activities (IVA) outside a radiation shelter, dose reductions to BFO in the range of 44-57% are demonstrated to be achievable with the spacesuit designs made only of water elements, or of multi-layer protection elements (with a thin layer of a high density material covering the water filled volume). Suit elements have a thickness in the range 2-6 cm and the total mass for the garment sums up to 35-43 kg depending on model and material combination. Dose reduction is converted into time gain, i.e. the increase of time interval between the occurrence of a SPE and the moment the dose limit to the BFO for acute effects is reached. Wearing a

  12. Space Radiation Heart Disease Risk Estimates for Lunar and Mars Missions

    Science.gov (United States)

    Cucinotta, Francis A.; Chappell, Lori; Kim, Myung-Hee

    2010-01-01

    The NASA Space Radiation Program performs research on the risks of late effects from space radiation for cancer, neurological disorders, cataracts, and heart disease. For mortality risks, an aggregate over all risks should be considered as well as projection of the life loss per radiation induced death. We report on a triple detriment life-table approach to combine cancer and heart disease risks. Epidemiology results show extensive heterogeneity between populations for distinct components of the overall heart disease risks including hypertension, ischaemic heart disease, stroke, and cerebrovascular diseases. We report on an update to our previous heart disease estimates for Heart disease (ICD9 390-429) and Stroke (ICD9 430-438), and other sub-groups using recent meta-analysis results for various exposed radiation cohorts to low LET radiation. Results for multiplicative and additive risk transfer models are considered using baseline rates for US males and female. Uncertainty analysis indicated heart mortality risks as low as zero, assuming a threshold dose for deterministic effects, and projections approaching one-third of the overall cancer risk. Medan life-loss per death estimates were significantly less than that of solid cancer and leukemias. Critical research questions to improve risks estimates for heart disease are distinctions in mechanisms at high doses (>2 Gy) and low to moderate doses (<2 Gy), and data and basic understanding of radiation doserate and quality effects, and individual sensitivity.

  13. CFD-simulation of radiator for air cooling of microprocessors in a limitided space

    Directory of Open Access Journals (Sweden)

    Trofimov V. E.

    2016-12-01

    Full Text Available One of the final stages of microprocessors development is heat test. This procedure is performed on a special stand, the main element of which is the switching PCB with one or more mounted microprocessor sockets, chipsets, interfaces, jumpers and other components which provide various modes of microprocessor operation. The temperature of microprocessor housing is typically changed using thermoelectric module. The cold surface of the module with controlled temperature is in direct thermal contact with the microprocessor housing designed for cooler installation. On the hot surface of the module a radiator is mounted. The radiator dissipates the cumulative heat flow from both the microprocessor and the module. High density PCB layout, the requirement of free access to the jumpers and interfaces, and the presence of numerous sensors limit the space for radiator mounting and require the use of an extremely compact radiator, especially in air cooling conditions. One of the possible solutions for this problem may reduce the area of the radiator heat-transfer surfaces due to a sharp growth of the heat transfer coefficient without increasing the air flow rate. To ensure a sharp growth of heat transfer coefficient on the heat-transfer surface one should make in the surface one or more dead-end cavities into which the impact air jets would flow. CFD simulation of this type of radiator has been conducted. The heat-aerodynamic characteristics and design recommendations for removing heat from microprocessors in a limited space have been determined.

  14. Radiation shielding aspects for long manned mission to space: Criteria, survey study, and preliminary model

    OpenAIRE

    Sztejnberg Manuel; Xiao Shanjie; Satvat Nader; Limón Felisa; Hopkins John; Jevremović Tatjana

    2006-01-01

    The prospect of manned space missions outside Earth's orbit is limited by the travel time and shielding against cosmic radiation. The chemical rockets currently used in the space program have no hope of propelling a manned vehicle to a far away location such as Mars due to the enormous mass of fuel that would be required. The specific energy available from nuclear fuel is a factor of 106 higher than chemical fuel; it is therefore obvious that nuclear power production in space is a must. On th...

  15. The Effect of Topography on the Exposure of Airless Bodies to Space Radiation: Phobos Case Study

    Science.gov (United States)

    Stubbs, T. J.; Wang, Y.; Guo, J.; Schwadron, N.; Cooper, J. F.; Wimmer-Schweingruber, R. F.; Spence, H. E.; Jordan, A.; Sturner, S. J.; Glenar, D. A.; Wilson, J. K.

    2017-12-01

    The surfaces of airless bodies, such as the Moon and Phobos (innermost Martian moon), are directly exposed to the surrounding space environment, including energetic particle radiation from both the ever-present flux of galactic cosmic rays (GCRs) and episodic bursts of solar energetic particles (SEPs). Characterizing this radiation exposure is critical to our understanding of the evolution of these bodies from space weathering processes, such as radiation damage of regolith, radiolysis of organics and volatiles, and dielectric breakdown. Similarly, this also has important implications for the long-term radiation exposure of future astronauts and equipment on the surface. In this study, the focus is the influence of Phobian topography on the direct exposure of Phobos to space radiation. For a given point on its surface, this exposure depends on: (i) the solid angle subtended by the sky, (ii) the solid angle of the sky blocked by Mars, and (iii) the energy and angular distributions of ambient energetic particle populations. The sky solid angle, determined using the elevation of the local horizon calculated from a digital elevation model (DEM), can be significantly reduced around topographic lows, such as crater floors, or increased near highs like crater rims. The DEM used in this study was produced using images from the Mars Express High Resolution Stereo Camera (HRSC), and has the highest available spatial resolution ( 100m). The proximity of Phobos to Mars means the Martian disk appears large in the Phobian sky, but this only effects the moon's near side due its tidally locked orbit. Only isotropic distributions of energetic particles are initially considered, which is typically a reasonable assumption for GCRs and sometimes for SEPs. Observations of the radiation environments on Mars by Curiosity's Radiation Assessment Detector (RAD), and the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) onboard the Lunar Reconnaissance Orbiter (LRO) at the Moon

  16. Annual Conference on Nuclear and Space Radiation Effects, 19th, Las Vegas, NV, July 20-22, 1982, Proceedings

    Science.gov (United States)

    Long, D. M.

    1982-01-01

    The results of research concerning the effects of nuclear and space radiation are presented. Topics discussed include the basic mechanisms of nuclear and space radiation effects, radiation effects in devices, and radiation effects in microcircuits, including studies of radiation-induced paramagnetic defects in MOS structures, silicon solar cell damage from electrical overstress, radiation-induced charge dynamics in dielectrics, and the enhanced radiation effects on submicron narrow-channel NMOS. Also examined are topics in SGEMP/IEMP phenomena, hardness assurance and testing, energy deposition, desometry, and radiation transport, and single event phenomena. Among others, studies are presented concerning the limits to hardening electronic boxes to IEMP coupling, transient radiation screening of silicon devices using backside laser irradiation, the damage equivalence of electrons, protons, and gamma rays in MOS devices, and the single event upset sensitivity of low power Schottky devices.

  17. Annual Conference on Nuclear and Space Radiation Effects, 19th, Las Vegas, NV, July 20-22, 1982, Proceedings

    Science.gov (United States)

    Long, D. M.

    1982-12-01

    The results of research concerning the effects of nuclear and space radiation are presented. Topics discussed include the basic mechanisms of nuclear and space radiation effects, radiation effects in devices, and radiation effects in microcircuits, including studies of radiation-induced paramagnetic defects in MOS structures, silicon solar cell damage from electrical overstress, radiation-induced charge dynamics in dielectrics, and the enhanced radiation effects on submicron narrow-channel NMOS. Also examined are topics in SGEMP/IEMP phenomena, hardness assurance and testing, energy deposition, desometry, and radiation transport, and single event phenomena. Among others, studies are presented concerning the limits to hardening electronic boxes to IEMP coupling, transient radiation screening of silicon devices using backside laser irradiation, the damage equivalence of electrons, protons, and gamma rays in MOS devices, and the single event upset sensitivity of low power Schottky devices.

  18. Effects of autogamy in Paramecium tetraurelia on catalase activity and on radiosensitivity to natural ionizing radiations

    International Nuclear Information System (INIS)

    Croute, F.; Dupouy, D.; Charley, J.P.; Soleilhavoup, J.P.; Planel, H.

    1980-01-01

    Catalase activity of Paramecium tetraurelia decreased during autogamy and recovered to normal 5 days later. Autogamy also caused changes in the ciliate's sensitivity sensitivity to natural ionizing radiations - the decrease in cell growth rate previously described in shielded cultures did not occur when autogamous cells were used. Maximum effect of shielding was observed in 11-day-old postautogamous cells. The role of the catalase in the mechanism of natural irradiation effect is discussed

  19. Study on preparation of new antioxidants for radiation vulcanized natural rubber latex product. Antioxidant from keratin

    International Nuclear Information System (INIS)

    Nguyen Quoc Hien; Nguyen Van Toan; Vo Tan Thien; Le Hai

    2000-01-01

    The thermo-oxidative aging resistance of radiation vulcanization of natural rubber latex (RVNRL) products should be adequately by using suitable antioxidants or new kind of effective antioxidant. This work presents the results of preparation of natural antioxidant from hair keratin. Characteristics and effectiveness of resultant antioxidant are also presented. The results obtained indicates that antioxidant made from hair keratin is safe and effective for rubber products from RVNRL. (author)

  20. Radiation transport modeling and assessment to better predict radiation exposure, dose, and toxicological effects to human organs on long duration space flights

    Science.gov (United States)

    Denkins, P.; Badhwar, G.; Obot, V.; Wilson, B.; Jejelewo, O.

    2001-01-01

    NASA is very interested in improving its ability to monitor and forecast the radiation levels that pose a health risk to space-walking astronauts as they construct the International Space Station and astronauts that will participate in long-term and deep-space missions. Human exploratory missions to the moon and Mars within the next quarter century, will expose crews to transient radiation from solar particle events which include high-energy galactic cosmic rays and high-energy protons. Because the radiation levels in space are high and solar activity is presently unpredictable, adequate shielding is needed to minimize the deleterious health effects of exposure to radiation. Today, numerous models have been developed and used to predict radiation exposure. Such a model is the Space Environment Information Systems (SPENVIS) modeling program, developed by the Belgian Institute for Space Aeronautics. SPENVIS, which has been assessed to be an excellent tool in characterizing the radiation environment for microelectronics and investigating orbital debris, is being evaluated for its usefulness with determining the dose and dose-equivalent for human exposure. Thus far. the calculations for dose-depth relations under varying shielding conditions have been in agreement with calculations done using HZETRN and PDOSE, which are well-known and widely used models for characterizing the environments for human exploratory missions. There is disagreement when assessing the impact of secondary radiation particles since SPENVIS does a crude estimation of the secondary radiation particles when calculating LET versus Flux. SPENVIS was used to model dose-depth relations for the blood-forming organs. Radiation sickness and cancer are life-threatening consequences resulting from radiation exposure. In space. exposure to radiation generally includes all of the critical organs. Biological and toxicological impacts have been included for discussion along with alternative risk mitigation