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Sample records for dose gamma radiation

  1. Gamma Radiation Doses In Sweden

    International Nuclear Information System (INIS)

    Almgren, Sara; Isaksson, Mats; Barregaard, Lars

    2008-01-01

    Gamma dose rate measurements were performed in one urban and one rural area using thermoluminescence dosimeters (TLD) worn by 46 participants and placed in their dwellings. The personal effective dose rates were 0.096±0.019(1 SD) and 0.092±0.016(1 SD)μSv/h in the urban and rural area, respectively. The corresponding dose rates in the dwellings were 0.11±0.042(1 SD) and 0.091±0.026(1 SD)μSv/h. However, the differences between the areas were not significant. The values were higher in buildings made of concrete than of wood and higher in apartments than in detached houses. Also, 222 Rn measurements were performed in each dwelling, which showed no correlation with the gamma dose rates in the dwellings

  2. Low doses of gamma radiation in soybean

    International Nuclear Information System (INIS)

    Franco, José G.; Franco, Suely S.H.; Villavicencio, Anna L.C.; Arthur, Valter; Arthur, Paula B.; Franco, Caio H.

    2017-01-01

    The degree of radiosensitivity depends mostly on the species, the stage of the embryo at irradiation, the doses employed and the criteria used to measure the effect. One of the most common criteria to evaluate radiosensitivity in seeds is to measure the average plant production. Dry soya seeds were exposed to low doses of gamma radiation from source of Cobalt-60, type Gammecell-220, at 0.210 kGy dose rate. In order to study stimulation effects of radiation on germination, plant growth and production. A treatment with four radiation doses was applied as follows: 0 (control); 12.5; 25.0 and 50.0 Gy. Seed germination and harvested of number of seeds and total production were assessed to identify occurrence of stimulation. Soya seeds number and plants were handled as for usual seed production in Brazil. The low doses of gamma radiation in the seeds that stimulate the production were the doses of 12.5 and 50.0 Gy. The results show that the use of low doses of gamma radiation can stimulate germination and plant production. (author)

  3. Low doses of gamma radiation in soybean

    Energy Technology Data Exchange (ETDEWEB)

    Franco, José G.; Franco, Suely S.H.; Villavicencio, Anna L.C., E-mail: zegilmar60@gmail.com, E-mail: gilmita@uol.com.br, E-mail: villavic@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); Arthur, Valter; Arthur, Paula B., E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Franco, Caio H. [Universidade Federal de São Paulo (UNIFESP), SP (Brazil). Departamento de Microbiologia, Imunologia e Parasitologia

    2017-07-01

    The degree of radiosensitivity depends mostly on the species, the stage of the embryo at irradiation, the doses employed and the criteria used to measure the effect. One of the most common criteria to evaluate radiosensitivity in seeds is to measure the average plant production. Dry soya seeds were exposed to low doses of gamma radiation from source of Cobalt-60, type Gammecell-220, at 0.210 kGy dose rate. In order to study stimulation effects of radiation on germination, plant growth and production. A treatment with four radiation doses was applied as follows: 0 (control); 12.5; 25.0 and 50.0 Gy. Seed germination and harvested of number of seeds and total production were assessed to identify occurrence of stimulation. Soya seeds number and plants were handled as for usual seed production in Brazil. The low doses of gamma radiation in the seeds that stimulate the production were the doses of 12.5 and 50.0 Gy. The results show that the use of low doses of gamma radiation can stimulate germination and plant production. (author)

  4. Measurement of gamma radiation doses in nuclear power plant environment

    International Nuclear Information System (INIS)

    Bochvar, I.A.; Keirim-Markus, I.B.; Sergeeva, N.A.

    1976-01-01

    Considered are the problems of measuring gamma radiation dose values and the dose distribution in the nuclear power plant area with the aim of estimating the extent of their effect on the population. Presented are the dosimeters applied, their distribution throughout the controlled area, time of measurement. The distribution of gamma radiation doses over the controlled area and the dose alteration with the increase of the distance from the release source are shown. The results of measurements are investigated. The conclusion is made that operating nuclear power plants do not cause any increase in the gamma radiation dose over the area. Recommendations for clarifying the techniques for using dose-meters and decreasing measurement errors are given [ru

  5. Studying and measuring the gamma radiation doses in Homs city

    International Nuclear Information System (INIS)

    Sofaan, A. H.

    2001-01-01

    The gamma radiation dose was measured in Homs city by using many portable dosimeters (electronic dosimeter and Geiger-Muller). The measurements were carried out in the indoor and outdoor buildings, for different time period, through one year (1999-2000). High purity germanium detector with low back ground radiation (HpGe) was used to determine radiation element contained in some building and the surrounding soil. The statistical analysis laws were applied to make sure that the measured dose distribution around average value is normal distribution. The measurement indicates that the gamma indoor dose varies from 312μSv/y to 511μSv/y, with the average annual dose of 385μSv/y. However the gamma outdoor dose rate varies from 307μSv/y to 366μSv/y with an average annual dose 385μSv/y. The annual outdoor gamma radiation dose is about %16 lower than the outdoor dose in Homs City. These measurements have indicated that environmental gamma doses in Homs City are relatively low. This is because that most of the soils and rocks in the area are limestone. (author)

  6. Dose Rate of Environmental Gamma Radiation in Java Island

    International Nuclear Information System (INIS)

    Gatot Suhariyono; Buchori; Dadong Iskandar

    2007-01-01

    The dose rate Monitoring of environmental gamma radiation at some locations in Java Island in the year 2005 / 2006 has been carried out. The dose rate measurement of gamma radiation is carried out by using the peripheral of Portable Gamma of Ray Spectrometer with detector of NaI(Tl), Merck Exploranium, Model GR-130- MINISPEC, while to determine its geographic position is used by the GPS (Global Positioning System), made in German corporation of GPS III Plus type. The division of measurement region was conducted by dividing Java Island become 66 parts with same distance, except in Jepara area that will built PLTN (Nuclear Energy Power), distance between measurement points is more closed. The results of dose rate measurement are in 66 locations in Java Island the range of (19.24 ± 4.05) nSv/hour until (150.78 ± 12.26) nSv/hour with mean (51.93 ± 36.53) nSv/h. The lowest dose rate was in location of Garut, while highest dose rate was in Ujung Lemah Abang, Jepara location. The data can be used for base line data of dose rate of environmental gamma radiation in Indonesia, specially in Java Island. The mean level of gamma radiation in Java monitoring area (0.46 mSv / year) was still lower than worldwide average effective dose rate of terrestrial gamma rays 0.5 mSv / year (report of UNSCEAR, 2000). (author)

  7. Low doses effects and gamma radiations low dose rates

    International Nuclear Information System (INIS)

    Averbeck, D.

    1999-01-01

    This expose wishes for bringing some definitions and base facts relative to the problematics of low doses effects and low dose rates effects. It shows some already used methods and some actual experimental approaches by focusing on the effects of ionizing radiations with a low linear energy transfer. (N.C.)

  8. In vitro cell culture lethal dose submitted to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Carolina S.; Rogero, Sizue O.; Rogero, Jose Roberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: carolina_sm@hotmail.com; Ikeda, Tamiko I.; Cruz, Aurea S. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil)

    2009-07-01

    The present study was designed to evaluate the in vitro effect of gamma radiation in cell culture of mouse connective tissue exposed to different doses of gamma radiation and under several conditions. The cell viability was analyzed by neutral red uptake methodology. This assay was developed for establish a methodology to be used in the future in the study of resveratrol radioprotection. Resveratrol (3,4',5- trihydroxystilbene), a phenolic phytoalexin that occurs naturally in some spermatophytes, such as grapevines, in response to injury as fungal infections and exposure to ultraviolet light. In the wines this compound is found at high levels and is considered one of the highest antioxidant constituents. The intense antioxidant potential of resveratrol provides many pharmacological activities including cardioprotection, chemoprevention and anti-tumor effects. Our results demonstrated that {sup 60}Co gamma radiation lethal dose (LD50) on NCTC clone 929 cells was about 340Gy. (author)

  9. In vitro cell culture lethal dose submitted to gamma radiation

    International Nuclear Information System (INIS)

    Moreno, Carolina S.; Rogero, Sizue O.; Rogero, Jose Roberto; Ikeda, Tamiko I.; Cruz, Aurea S.

    2009-01-01

    The present study was designed to evaluate the in vitro effect of gamma radiation in cell culture of mouse connective tissue exposed to different doses of gamma radiation and under several conditions. The cell viability was analyzed by neutral red uptake methodology. This assay was developed for establish a methodology to be used in the future in the study of resveratrol radioprotection. Resveratrol (3,4',5- trihydroxystilbene), a phenolic phytoalexin that occurs naturally in some spermatophytes, such as grapevines, in response to injury as fungal infections and exposure to ultraviolet light. In the wines this compound is found at high levels and is considered one of the highest antioxidant constituents. The intense antioxidant potential of resveratrol provides many pharmacological activities including cardioprotection, chemoprevention and anti-tumor effects. Our results demonstrated that 60 Co gamma radiation lethal dose (LD50) on NCTC clone 929 cells was about 340Gy. (author)

  10. Determination of dose factors for external gamma radiation in dwellings

    International Nuclear Information System (INIS)

    Maduar, M.F.; Hiromoto, G.

    2000-01-01

    A significant contribution to the global population exposure to ionizing radiation arises from natural sources, especially from radionuclides present in terrestrial crust. Human activities can eventually increase that exposure to significant levels, from the point of view of radiological protection. The presence of natural radionuclides in building materials may lead to an increment of both external and internal radiation exposure of the population. External exposure in dwellings arises from gamma-emitter radionuclides existing in the walls, floor and ceiling of their rooms. Mathematical models can be used to predict external dose rates inside the room, known the radionuclide concentration activities in dwelling constituents. This paper presents a methodology for theoretical evaluation of external gamma doses due to radionuclides present in the walls of an hypothetical standard room. The room is modeled as three pairs of rectangular sheets with finite thickness. Assessment of doses was performed through the application of photon transport model, taking in account self-absorption and radiation buildup. As the external dose due to a particular radionuclide is proportional to its activity concentration, results are presented as dose factors, defined as a ratio of absorbed dose (nGy.h -1 ) to the activity concentration (Bq.kg -1 ), for each radionuclide. The radionuclides were assumed to be uniformly distributed in the building materials. Calculations were performed for concrete walls and results are presented for 40 K, 226 Ra, and 232 Th, taking in account, for dose calculations, all gamma emitters from 226 Ra and 232 Th decay chains. Sensitivity of the model was estimated by varying four of its input parameters within a reasonable range of applicability, while leaving all other parameters at fixed selected values. The parameters studied and respective ranges of variation were: for thickness, 5 to 60 cm; for density, 0.5 to 4 g.cm -3 ; for the room length, 1.5 to 10 m

  11. Terrestrial Gamma Radiation Dose Rate of West Sarawak

    Science.gov (United States)

    Izham, A.; Ramli, A. T.; Saridan Wan Hassan, W. M.; Idris, H. N.; Basri, N. A.

    2017-10-01

    A study of terrestrial gamma radiation (TGR) dose rate was conducted in west of Sarawak, covering Kuching, Samarahan, Serian, Sri Aman, and Betong divisions to construct a baseline TGR dose rate level data of the areas. The total area covered was 20,259.2 km2, where in-situ measurements of TGR dose rate were taken using NaI(Tl) scintillation detector Ludlum 19 micro R meter NaI(Tl) approximately 1 meter above ground level. Twenty-nine soil samples were taken across the 5 divisions covering 26 pairings of 9 geological formations and 7 soil types. A hyperpure Germanium detector was then used to find the samples' 238U, 232Th, and 40K radionuclides concentrations producing a correction factor Cf = 0.544. A total of239 measured data were corrected with Cf resulting in a mean Dm of 47 ± 1 nGy h-1, with a range between 5 nGy h-1 - 103 nGy h-1. A multiple regression analysis was conducted between geological means and soil types means against the corrected TGR dose rate Dm, generating Dg,s= 0.847Dg+ 0.637Ds- 22.313 prediction model with a normalized Beta equation of Dg,s= 0.605Dg+ 0.395Ds. The model has an 84.6% acceptance of Whitney- Mann test null hypothesis when tested against the corrected TGR dose rates.

  12. Modeling gamma radiation dose in dwellings due to building materials.

    Science.gov (United States)

    de Jong, Peter; van Dijk, Willem

    2008-01-01

    A model is presented that calculates the absorbed dose rate in air of gamma radiation emitted by building materials in a rectangular body construction. The basis for these calculations is formed by a fixed set of specific absorbed dose rates (the dose rate per Bq kg(-1) 238U, 232Th, and 40K), as determined for a standard geometry with the dimensions 4 x 5 x 2.8 m3. Using the computer codes Marmer and MicroShield, correction factors are assessed that quantify the influence of several room and material related parameters on the specific absorbed dose rates. The investigated parameters are the position in the construction; the thickness, density, and dimensions of the construction parts; the contribution from the outer leave; the presence of doors and windows; the attenuation by internal partition walls; the contribution from building materials present in adjacent rooms; and the effect of non-equilibrium due to 222Rn exhalation. To verify the precision, the proposed method is applied to three Dutch reference dwellings, i.e., a row house, a coupled house, and a gallery apartment. The averaged difference with MCNP calculations is found to be 4%.

  13. The annual terrestrial gamma radiation dose to the population of the urban Christchurch area

    International Nuclear Information System (INIS)

    Chapman, R.H.

    1983-01-01

    Natural terrestrial gamma radiation dose rates were measured with a high pressure ionization chamber at 70 indoor (195 site measurements) and 58 outdoor locations in the metropolitan Christchurch area. Based on these site measurements, the average gonad dose rate to the population from natural terrestrial gamma radiation was estimated to be 273+-56 microgray per annum. (auth)

  14. Biological responses to low dose rate gamma radiation

    International Nuclear Information System (INIS)

    Magae, Junji; Ogata, Hiromitsu

    2003-01-01

    Linear non-threshold (LNT) theory is a basic theory for radioprotection. While LNT dose not consider irradiation time or dose-rate, biological responses to radiation are complex processes dependent on irradiation time as well as total dose. Moreover, experimental and epidemiological studies that can evaluate LNT at low dose/low dose-rate are not sufficiently accumulated. Here we analyzed quantitative relationship among dose, dose-rate and irradiation time using chromosomal breakage and proliferation inhibition of human cells as indicators of biological responses. We also acquired quantitative data at low doses that can evaluate adaptability of LNT with statistically sufficient accuracy. Our results demonstrate that biological responses at low dose-rate are remarkably affected by exposure time, and they are dependent on dose-rate rather than total dose in long-term irradiation. We also found that change of biological responses at low dose was not linearly correlated to dose. These results suggest that it is necessary for us to create a new model which sufficiently includes dose-rate effect and correctly fits of actual experimental and epidemiological results to evaluate risk of radiation at low dose/low dose-rate. (author)

  15. The effect of Low-dose Gamma Radiation on the Bio-chemical ...

    African Journals Online (AJOL)

    Low-dose gamma radiation has been applied to intravenous fluids to enhance the sterility assurance levels. This study was undertaken to determine the stability of gamma irradiated 2.5 % dextrose, 2.5 % dextrose in saline, Ringers lactate and Gastrointestinal replacement fluid at doses of 0, 2, 4, 6, 8, 10 and 20 kGy.

  16. Exposure of luminous marine bacteria to low-dose gamma-radiation.

    Science.gov (United States)

    Kudryasheva, N S; Petrova, A S; Dementyev, D V; Bondar, A A

    2017-04-01

    The study addresses biological effects of low-dose gamma-radiation. Radioactive 137 Cs-containing particles were used as model sources of gamma-radiation. Luminous marine bacterium Photobacterium phosphoreum was used as a bioassay with the bioluminescent intensity as the physiological parameter tested. To investigate the sensitivity of the bacteria to the low-dose gamma-radiation exposure (≤250 mGy), the irradiation conditions were varied as follows: bioluminescence intensity was measured at 5, 10, and 20°С for 175, 100, and 47 h, respectively, at different dose rates (up to 4100 μGy/h). There was no noticeable effect of gamma-radiation at 5 and 10°С, while the 20°С exposure revealed authentic bioluminescence inhibition. The 20°С results of gamma-radiation exposure were compared to those for low-dose alpha- and beta-radiation exposures studied previously under comparable experimental conditions. In contrast to ionizing radiation of alpha and beta types, gamma-emission did not initiate bacterial bioluminescence activation (adaptive response). As with alpha- and beta-radiation, gamma-emission did not demonstrate monotonic dose-effect dependencies; the bioluminescence inhibition efficiency was found to be related to the exposure time, while no dose rate dependence was found. The sequence analysis of 16S ribosomal RNA gene did not reveal a mutagenic effect of low-dose gamma radiation. The exposure time that caused 50% bioluminescence inhibition was suggested as a test parameter for radiotoxicity evaluation under conditions of chronic low-dose gamma irradiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    International Nuclear Information System (INIS)

    Jahn, W.; Piesch, E.

    1975-01-01

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

  18. Ionizing radiation population doses at Sao Paulo city, Brazil: open-pit gamma dose measurement

    International Nuclear Information System (INIS)

    Oliveira, Raimundo Enoch Rodrigues

    2001-01-01

    The effects of ionizing radiation to the human beings are well known for high and intermediate doses. As far as low level) radiation doses are concerned, there is no consensus. In order to get a better understanding of such effects it is necessary to assess the low doses with better accuracy. In this work, it was made an estimate of the annual ambient dose equivalent (H * (10)) to which the people are exposed in the city of Sao Paulo. Until now there are no data about it available in the literature. For the purpose of this evaluation, a map with various routes covering the largest and more representative area of the city was designed. The choice of points for data collection was made taking into account mainly the occupancy of the region. A portable gamma spectrometry system was used. It furnishes the rate of H * (10) and the measured gamma spectrum (in the range from 50 to 1670 keV) in the place of interest. The measurements were performed in a short time interval, since the gamma radiation arrives from a great extent of soil. Each measurement was done 1 m above the soil during 300 s. The rates of H * (10) varied from 33.1 to 152.3 nSv.h -1 , net values, obtained after subtraction of the cosmic rays contribution. The standard deviation was 22 n Sv.h -1 for an average for the city of Sao Paulo of 96.1(24) nSv.h -1 . In addition, average values of H * (10) rates for the city Health Divisions were calculated. Those values are not statistically equivalent and the whole set of data could not be treated as one, as the statistical Student test indicated a non homogeneity of the group of data. Hence it is necessary the accomplishment of a more detailed survey in order to verify the origin of the discrepancy. The mean value of H * (10) rate obtained for the city of Sao Paulo as converted to effective dose. in order to be compared with other places results It could be noticed that the annual average of effective dose for the city of Sao Paulo, 0.522(13) mSv, is superior to

  19. Gamma radiation dose from radionuclides in Kong Kong soil

    International Nuclear Information System (INIS)

    Leung, K.C.

    1990-01-01

    Calculations have been made of the γ dose rate at one metre above ground from the results of measurements of radionuclide concentrations in soil at various locations in Hong Kong and prior to the Chernobyl accident. The average dose rate is found to be 0.076 μGy h -1 , or 0.67 mGy year -1 . The contribution from fallout nuclides to the annual dose is shown to be small, at about 0.4% of the total. The calculated dose rate in this work is about 80% higher than the world average given by the United Nations Scientific Committee on the Effects of Atomic Radiation, in Ionizing Radiation: Sources and Biological Effects, Annex B (Exposure to natural radiation sources). A United Nations Publication, 1982. (author)

  20. Effect of gamma radiation dose and sensitizer on the physical properties of irradiated natural rubber latex

    International Nuclear Information System (INIS)

    Komgrit, R.; Thawat, C.; B, Tripob; Wirach, T.

    2009-07-01

    Full text: The vulcanization of natural rubber latex can be induced by gamma radiation, which enhances cross-linking within the rubber matrix. The purpose of this research is to investigate the effect of gamma radiation dose and sensitizers on the physical properties of irradiated natural rubber. Three sensitizers n-butyl acrylate (n-B A), tetrachloroethylene (C 2 Cl 4 ) and trichloromethane (CHCl 3 ) were mixed with natural rubber latex before irradiation with gamma ray dose varied from 14 to 22 kGy. Results showed that the mixture of three sensitizers with specific ratios effectively induced the cross-linking of natural rubber latex. The cross-linking ratio and improved physical properties increased with increasing gamma dose. Therefore, the mixture ratios of n-B A, C 2 Cl 4 and CHCl 3 have shown to be a critical parameter in the vulcanization of natural rubber latex by gamma radiation

  1. Measurement of gamma radiation doses at the RA reactor by thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Prokic, M.

    1974-01-01

    This paper presents the procedures and gamma radiation doses measured at the exit from the horizontal experimental channel HK-5, vertical experimental channel VK-5 and in the thermal column of the RA reactor in Vinca. Measurement of gamma radiation dose in the mixed intense gamma and neutron radiation field was done by two types of thermoluminescent dosemeters, LiF (TLD-700) and CaF 2 (TLD-08). Gamma dose in the VK-5 was measured in the air and on the bottle filled with tissue-equivalent solution. Increase of the dose on the surface of the bottle was 2.3 compared to the gamma dose value in the air. Correction for the influence of neutrons having different energies was done by using the known sensitivity values of both TL dosemeter types for thermal, intermediate and fast neutrons. Results showed that the TLD-700 dosemeter contains 5 time more Li-6 isotopes (0.035%) than the declared value causing increased neutron sensitivity of this dosemeter. This paper includes numerical sensitivity data for neutrons of different energies for both types of TL dosemeters. Neutron sensitivity values for TLD-700 are related to LiF with 0.035% of Li-6 isotope. Result of measurement have also shown that the CaF 2 :Mn (TLD-08) thermoluminescent dosemeter is more suitable for gamma radiation dose measurements in mixed n-gamma fields with intensive neutron fluxes due to lower neutron sensitivity compared to TLD-700 [sr

  2. Dose Response Model of Biological Reaction to Low Dose Rate Gamma Radiation

    International Nuclear Information System (INIS)

    Magae, J.; Furikawa, C.; Hoshi, Y.; Kawakami, Y.; Ogata, H.

    2004-01-01

    It is necessary to use reproducible and stable indicators to evaluate biological responses to long term irradiation at low dose-rate. They should be simple and quantitative enough to produce the results statistically accurate, because we have to analyze the subtle changes of biological responses around background level at low dose. For these purposes we chose micronucleus formation of U2OS, a human osteosarcoma cell line, as indicators of biological responses. Cells were exposed to gamma ray in irradiation rom bearing 50,000 Ci 60Co. After irradiation, they were cultured for 24 h in the presence of cytochalasin B to block cytokinesis, and cytoplasm and nucleus were stained with DAPI and prospidium iodide, respectively. the number of binuclear cells bearing micronuclei was counted under a fluorescence microscope. Dose rate in the irradiation room was measured with PLD. Dose response of PLD is linear between 1 mGy to 10 Gy, and standard deviation of triplicate count was several percent of mean value. We fitted statistically dose response curves to the data, and they were plotted on the coordinate of linearly scale response and dose. The results followed to the straight line passing through the origin of the coordinate axes between 0.1-5 Gy, and dose and does rate effectiveness factor (DDREF) was less than 2 when cells were irradiated for 1-10 min. Difference of the percent binuclear cells bearing micronucleus between irradiated cells and control cells was not statistically significant at the dose above 0.1 Gy when 5,000 binuclear cells were analyzed. In contrast, dose response curves never followed LNT, when cells were irradiated for 7 to 124 days. Difference of the percent binuclear cells bearing micronucleus between irradiated cells and control cells was not statistically significant at the dose below 6 Gy, when cells were continuously irradiated for 124 days. These results suggest that dose response curve of biological reaction is remarkably affected by exposure

  3. Dose rate effect on material aging due to radiation. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Shin-ichi (Radiation Center of Osaka Prefecture, Sakai (Japan)); Hayakawa, Chikara; Takeya, Chikashi

    1982-12-01

    Although many reports have been presented on the radiation aging of the organic materials for electric cables, those have been based on the experiments carried out at high dose rate near 1 x 10/sup 6/ rad/h, assuming that aging effect depends on only radiation dose. Therefore, to investigate the aging behaviour in low dose rate range is an important subject to predict their practical life time. In this report, the results of having investigated the aging behaviour of six types of materials are described, (polyethylene for general insulation purpose, chemically cross-linked polyethylene, fire-retardant chemically cross-linked polyethylene, fire-retardant ethylene-propylene rubber, fire-retardant chloro-sulfonated polyethylene for sheaths, and fire-retardant, low hydrochloric acid, special heat-resistant vinyl for insulation purpose or chloroclean). They were irradiated with /sup 60/Co ..gamma..-ray at the dose from 5 x 10/sup 3/ to 1 x 10/sup 6/ rad/h, and their deterioration was tested for the items of elongation, tensile strength, resistivity, dielectric tangent and gel fraction. The aging mechanism and dose rate effect were also considered. The dose rate effect appeared or did not appear depending on the types of materials and also their properties. The materials that showed the dose rate effect included the typical ones whose characteristics degraded with the decreasing dose rate, and the peculiar ones whose deterioration of characteristics did not appear constantly. Aging mechanism may vary in the case of high dose rate and low dose rate. Also, if the life time at respective dose rate in relatively higher dose rate region is clarified, the life time in low dose rate region may possibly be predicted.

  4. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Cantinha, Rebeca S.; Nakano, Eliana; Silva, Luanna R.S.

    2009-01-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of 60 Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD 50 obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  5. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Cantinha, Rebeca S.; Nakano, Eliana [Instituto Butantan, Sao Paulo, SP (Brazil). Lab. de Parasitologia], e-mail: rebecanuclear@gmail.com, e-mail: eliananakano@butantan.gov.br; Borrely, Sueli I. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes], e-mail: sborrely@ipen.br; Amaral, Ademir; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia (GERAR)], e-mail: amaral@ufpe.br; Silva, Luanna R.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia], e-mail: amdemelo@hotmail.com, e-mail: luannaribeiro_lua@hotmail.com

    2009-07-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of {sup 60}Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD{sub 50} obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  6. Isodose mapping of terrestrial gamma radiation dose rate of Selangor state, Kuala Lumpur and Putrajaya, Malaysia

    International Nuclear Information System (INIS)

    Sanusi, M.S.M.; Ramli, A.T.; Gabdo, H.T.; Garba, N.N.; Heryanshah, A.; Wagiran, H.; Said, M.N.

    2014-01-01

    A terrestrial gamma radiation survey for the state of Selangor, Kuala Lumpur and Putrajaya was conducted to obtain baseline data for environmental radiological health practices. Based on soil type, geological background and information from airborne survey maps, 95 survey points statistically representing the study area were determined. The measured doses varied according to geological background and soil types. They ranged from 17 nGy h −1 to 500 nGy h −1 . The mean terrestrial gamma dose rate in air above the ground was 182 ± 81 nGy h −1 . This is two times higher than the average dose rate of terrestrial gamma radiation in Malaysia which is 92 nGy h −1 (UNSCEAR 2000). An isodose map was produced to represent exposure rate from natural sources of terrestrial gamma radiation. - Highlights: • A methodology is presented to reduce terrestrial gamma dose rate field survey. • Geological background of acid intrusive of granitic type has the highest dose rates. • The mean dose rate is 2 times higher than the world average. • Isodose map of terrestrial gamma radiation for Selangor, Kuala Lumpur and Putrajaya was produced

  7. Calibration curve to establish the exposure dose at Co60 gamma radiation

    International Nuclear Information System (INIS)

    Guerrero C, C.; Brena V, M.

    2000-01-01

    The biological dosimetry is an adequate method for the dose determination in cases of overexposure to ionizing radiation or doubt of the dose obtained by physical methods. It is based in the aberrations analysis produced in the chromosomes. The behavior of leisure in chromosomes is of dose-response type and it has been generated curves in distinct laboratories. Next is presented the curve for gamma radiation produced in the National Institute of Nuclear Research (ININ) laboratory. (Author)

  8. Dose-dependent hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to sublethal doses of gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Song, You, E-mail: you.song@niva.no [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway); Salbu, Brit; Teien, Hans-Christian; Heier, Lene Sørlie [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Rosseland, Bjørn Olav [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian University of Life Sciences (NMBU), Department of Ecology and Natural Resource Management, P.O. Box 5003, N-1432 Ås (Norway); Tollefsen, Knut Erik [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway)

    2014-11-15

    Highlights: • First study on early stress responses in salmon exposed to low-dose gamma radiation. • Dramatic dose-dependent transcriptional responses characterized. • Multiple modes of action proposed for gamma radiation. - Abstract: Due to the production of free radicals, gamma radiation may pose a hazard to living organisms. The high-dose radiation effects have been extensively studied, whereas the ecotoxicity data on low-dose gamma radiation is still limited. The present study was therefore performed using Atlantic salmon (Salmo salar) to characterize effects of low-dose (15, 70 and 280 mGy) gamma radiation after short-term (48 h) exposure. Global transcriptional changes were studied using a combination of high-density oligonucleotide microarrays and quantitative real-time reverse transcription polymerase chain reaction (qPCR). Differentially expressed genes (DEGs; in this article the phrase gene expression is taken as a synonym of gene transcription, although it is acknowledged that gene expression can also be regulated, e.g., at protein stability and translational level) were determined and linked to their biological meanings predicted using both Gene Ontology (GO) and mammalian ortholog-based functional analyses. The plasma glucose level was also measured as a general stress biomarker at the organism level. Results from the microarray analysis revealed a dose-dependent pattern of global transcriptional responses, with 222, 495 and 909 DEGs regulated by 15, 70 and 280 mGy gamma radiation, respectively. Among these DEGs, only 34 were commonly regulated by all radiation doses, whereas the majority of differences were dose-specific. No GO functions were identified at low or medium doses, but repression of DEGs associated with GO functions such as DNA replication, cell cycle regulation and response to reactive oxygen species (ROS) were observed after 280 mGy gamma exposure. Ortholog-based toxicity pathway analysis further showed that 15 mGy radiation

  9. Effects of low dose gamma radiation on the early growth of red pepper and the resistance to subsquent high dose of radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. S.; Baek, M. H.; Kim, D. H.; Lee, Y. K. [KAERI, Taejon (Korea, Republic of); Lee, Y. B. [Chungnam National Univ., Taejon (Korea, Republic of)

    2001-05-01

    Red pepper (capsicum annuum L. cv. Jokwang and cv. Johong) seeds were irradiated with the dose of 0{approx}50 Gy to investigated the effect of the low dose gamma radiation on the early growth and resistance to subsequent high dose of radiation. The effect of the low dose gamma radiation on the early growth and resistance to subsequenct high dose of radiation were enhanced in Johong cultivar but not in Jokwang cultivar. Germination rate and early growth of Johong cultivar were noticeably increased at 4 Gy-, 8 Gy- and 20 Gy irradiation group. Resistance to subsequent high dose of radiation of Johong cultivar were increased at almost all of the low dose irradiation group. Especially it was highest at 4 Gy irradiation group. The carotenoid contents and enzyme activity on the resistance to subsequent high dose of radiation of Johong cultivar were increased at the 4 Gy and 8 Gy irradiation group.

  10. An energy-independent dose rate meter for beta and gamma radiation

    International Nuclear Information System (INIS)

    Heinzelmann, M.; Keller, M.

    1986-01-01

    An easy to handle dose rate meter has been developed at the Juelich Nuclear Research Centre with a small probe for the energy-independent determination of the dose rate in mixed radiation fields. The dose rate meter contains a small ionisation chamber with a volume of 15.5 cm 3 . The window of the ionisation chamber consists of an aluminised plastic foil of 7 mg.cm -2 . The dose rate meter is suitable for determining the dose rate in skin. With a supplementary depth dose cap, the dose rate can be determined in tissue at a depth of 1 cm. The dose rate meter is energy-independent within +-20% for 147 Pm, 204 Tl and 90 Sr/ 90 Y beta radiation and for gamma radiation in the energy range above 35 keV. (author)

  11. A study on the effect of low doses gamma radiation on mushroom spawn

    International Nuclear Information System (INIS)

    Ajlouni, Said

    1993-03-01

    Mushroom spawn (Hybrid-521) was irradiated at room temperature using low doses of gamma radiation (50-600 rad). The spawn was then planted at two stages; first, after 24 hours of irradiation, and second after storage for three weeks at refrigeration temperature. Results of this study showed that the applied doses of gamma radiation did not have any stimulatory effect on mushroom growth or productivity. It was also noticed that mushroom production rate decreased when irradiated spawn was stored for three weeks prior to planting, as compared with spawn planted 24 hours after irradiation. (author). 18 refs., 2 figs., 2 tabs

  12. Effect of low-doses gamma radiation on physico-chemical properties of cereal starches

    International Nuclear Information System (INIS)

    Gambus, H.; Juszczak, L.; Achremowicz, B.

    1995-01-01

    Wheat starch of Emika variety was treated with 3 and 5 kGy doses of gamma radiation, rye starch of Dankowskie Zlote variety and triticale starch of Dagro variety - with 3 kGy doses. Radiation of this starch caused an increase of reduction ability and water solubility at 60 and 80 o C. However with the increased radiation doses a significant decrease of maximum viscosity and of the viscosity of starch pastes being cooled to 50% was observed. Mild radiopolimerization also decreased the degree of retrogradation of wheat and rye starch pastes stored at above 0 o C. (author)

  13. Sterilization and lethal gamma radiation doses on adults and eggs of Sitotroga Cerealella (OLIVIER)

    International Nuclear Information System (INIS)

    Wiendl, F.M.; Bovi, O.A.; Arthur, V.

    1975-04-01

    The influence of lethal doses of radiation from a cobalt 60 gamma source on eggs, adults and fertitility of Sitotroga Cerealella (Olivier) is described. Eggs irradiated with a dose of 14 Krad still showed viability of 16.1%. On longevity doses up to 70 Krad were usually non lethal but some variation could be observed related to the larval diet. Females fertilized by males irradiated with a dose of 70 Krad produced 36% fertile eggs. When the females were irradiated with the same dose, their fertility dropped to 2.2% and when both sexes were irradiated with a 60 Krad dose, the fertility was 28.8%

  14. Evaluation of mathematical methods for predicting optimum dose of gamma radiation in sugarcane (Saccharum sp.)

    International Nuclear Information System (INIS)

    Wu, K.K.; Siddiqui, S.H.; Heinz, D.J.; Ladd, S.L.

    1978-01-01

    Two mathematical methods - the reversed logarithmic method and the regression method - were used to compare the predicted and the observed optimum gamma radiation dose (OD 50 ) in vegetative propagules of sugarcane. The reversed logarithmic method, usually used in sexually propagated crops, showed the largest difference between the predicted and observed optimum dose. The regression method resulted in a better prediction of the observed values and is suggested as a better method for the prediction of optimum dose for vegetatively propagated crops. (author)

  15. Level of terrestrial gamma radiation and doses to population in Jiangsu province

    International Nuclear Information System (INIS)

    1985-01-01

    In this paper the results of investigation of terrestrial gamma radiation level in Jiangsu Province are reported and the population doses due to this radiation are estimated. The sketch map of the geographical distribution of the terrestrial gamma radiation level is given. In this investigation FD-71 portable scintillation counters and RSS-111 high pressure ionization chambers were used. The results showed that the terrestrial gamma absorbed dose rates in air for indoors and outdoors were 10.7 x 10 -8 Gy/h and 6.5 x 10 -8 Gy/h (weighted values) respectively. The indoors-to-outdoors ratio was 1.65. The total (indoor plus outdoor) annual effective dose equivalent from terrestrial gamma radiation, averaged over the population in this province, was 6.0 x 10 -4 Sv. The collective annual effective dose equivalent was 3.6 x 10 4 man.Sv. Therefore, the absorbed dose to population in Jiangsu Province is in the range of the normal background

  16. Effect of different doses of gamma radiation on shelf life of mango (Mangifera indica L.) fruits cv. Dashehari

    International Nuclear Information System (INIS)

    Baghel, B.S.; Gupta, N.; Tiwari, R.

    2005-01-01

    The mango fruits cv. Dashehari irradiated with different doses of gamma radiation for extending their shelf life and for stabilizing the market demand, revealed that irradiation of mango fruits with 200 Gy gamma radiation increase the post harvest life of 93.75 percent mango fruits by 12 days over control (46.66 percent) and proved superior to maintain the considerable physico-chemical composition of mango fruits as compared to control and higher doses of gamma radiation. (author)

  17. Geological influence on terrestrial gamma radiation dose rate in the Malaysian State of Johore

    International Nuclear Information System (INIS)

    Ramli, A.T.; Hussein, A.W.M.A.; Lee, M.H.

    2001-01-01

    Measurements of environmental terrestrial gamma radiation dose-rate (TGRD) have been made in Johore, Malaysia. The focus is on determining a relationship between geological type and TGRD levels. Data were compared using the one way analysis of variance (ANOVA), in some instances revealing significant differences between TGRD measurements and the underlying geological structure

  18. Gamma-irradiated onions as a biological indicator of radiation dose

    International Nuclear Information System (INIS)

    Vaijapurkar, S.G.; Agarwal, Deepshikha; Chaudhuri, S.K.; Ram Senwar, Kana; Bhatnagar, P.K.

    2001-01-01

    Post-irradiation identification and dose estimation are required to assess the radiation-induced effects on living things in any nuclear emergency. In this study, radiation-induced morphological/cytological changes i.e., number of root formation and its length, shooting length, reduction in mitotic index, micronuclei formation and chromosomal aberrations in the root tip cells of gamma-irradiated onions at lower doses (50-2000 cGy) are reported. The capabilities of this biological species to store the radiation-induced information are also studied

  19. The influence of geology on terrestrial gamma radiation dose rate in Pahang state, Malaysia

    International Nuclear Information System (INIS)

    Gabdo, H.T.; Ramli, A.T.; Sanusi, M.S.; Garba, N.N.; Saleh, M.A.

    2015-01-01

    Terrestrial gamma radiation dose (TGRD) rate measurements have been made in Pahang state, Malaysia. Significant variations were found between TGRD measurements and the underlying geological formations. In some cases revealing significant elevations of TGRD. The acid-intrusive geological formation has the highest mean TGRD measurement of 367 nGy/h -1 . This is more than six times the world average value of 59 nGy/h -1 , while the quaternary geological formation has the lowest mean gamma radiation dose rate of 99 nGy h -1 . The annual effective dose equivalent outdoor to the population was 0.216 mSv. The lifetime equivalent dose and relative lifetime cancer risks for an individual living in Pahang state were 81 mSv and 4.7 x 10 -3 respectively. These values are more than two times the world average of 34 mSv and 1.95 x 10 -3 respectively. (author)

  20. Terrestrial gamma radiation dose rates and radiological mapping of Terengganu state, Malaysia

    International Nuclear Information System (INIS)

    Garba, N.N.

    2015-01-01

    Measurement of terrestrial gamma radiation dose (TGRD) rates in Terengganu state, Malaysia was carried out from 145 different locations using NaI[Tl] micro roentgen survey meter. The measured TGRD rates ranged from 35 to 340 nGy h -1 with mean value of 150 nGy h -1 . The annual effective dose to population was found to be 0.92 mSv y -1 . The data obtained were used in constructing the gamma isodose map using ArcGis 9.3 which shows the distribution of TGRD rates across the state. (author)

  1. Responses of rat R-1 cells to low dose rate gamma radiation and multiple daily dose fractions

    International Nuclear Information System (INIS)

    Kal, H.B.; Bijman, J.Th.

    1981-01-01

    Multifraction irradiation may offer the same therapeutic gain as continuous irradiation. Therefore, a comparison of the efficacy of low dose rate irradiation and multifraction irradiation was the main objective of the experiments to be described. Both regimens were tested on rat rhabdomyosarcoma (R-1) cells in vitro and in vivo. Exponentially growing R-1 cells were treated in vitro by a multifraction irradiation procedure with dose fractions of 2 Gy gamma radiation and time intervals of 1 to 3 h. The dose rate was 1.3 Gy.min -1 . The results indicate that multifractionation of the total dose is more effective with respect to cell inactivation than continuous irradiation. (Auth.)

  2. Effect of sublethal doses of gamma radiation on DNA super helicity and survival of human fibroblasts

    International Nuclear Information System (INIS)

    Koceva-Chyla, A.

    1992-01-01

    Effect of sublethal doses of gamma radiation on cell survival and DNA super helicity in human fibroblasts was studied. Cell survival was estimated on the basis the basis of clonal growth of irradiated fibroblasts in monolayer culture in vitro. The nucleoid sedimentation technique was used to study ionizing radiation-induced DNA damage in vivo as well as to examine DNA super helicity. Increased concentrations of ethidium bromine (EB) were used to titrate the DNA super coiling response in non-irradiated cells. This response consisted of a relaxation phase (1-5 μg/ml EB) and rewinding phase (5-20 μg/ml EB). Observed biphasic dependence of sedimentation distance of nucleoid on the concentration of EB suggests the dye altered the amount of DNA super coiling in situ. The degree of DNA super coiling and thus the sedimentation rate of nucleoid in absence of EB was very sensitive to strand break induced in DNA by the doses of gamma radiation employed in the cell survival assay. Doses of 2-8 Gy of gamma radiation induced a dose -dependent reduction in the sedimentation of nucleoid. Loss of negative DNA super coiling was initially rapid (about 30% after the dose of 2 Gy) and then proceeded at a slower rate (about 35% and 48% after the doses of 4 Gy and 8 Gy respectively), indicating a significant relaxation of nucleoid structure at the doses of gamma radiation greater than 4 Gy, at which also significant decrease in fibroblasts survival occurred. Significant loss of negative DNA super coiling within the range of doses of gamma radiation resulting in significant decrease of cell survival suggests that destabilizing effect of radiation on DNA tertiary- and quaternary structures (extensive DNA breaks and relaxation of nucleonic super helicity) disturb normal functions and replications of genomic DNA, in consequence leading to a reproductive death of cells. Considering the sensitivity and simplicity of the method, the nucleoid sedimentation technique might be also a useful tool

  3. The analogy research study on gamma radiation dose rate of radioisotopes 131Ba and 131I

    International Nuclear Information System (INIS)

    Hu Youhua; Feng Guangwen

    2013-01-01

    Analogy is a inference method ,according some properties of a class of things to inferring the similar things should also have the similar properties. The analogy of same radionuclides is widely used in radioisotope logging environment impact assessment so far. This paper is to provide fFor future providing a theoretical calculation method and analogy method between different radionuclides in radioisotope logging environment impact assessment. In this paper, using the latest decay scheme, through theoretical modeling, the aim is the the establishment of 131 Ba and 131 I radioisotopes gamma radiation dose rate calculation method, and try to carry out analogy research on gamma radiation dose rate of different radioisotopes with the same activity. The results show that the analogy of different radionuclides is feasible, which provides the new method reference for carrying out such radiation environmental impact assessment in future. (authors)

  4. External gamma radiation dose studies in the proposed uranium mining areas of Andhra Pradesh, India

    International Nuclear Information System (INIS)

    Reddy, P.; Reddy, K.; Reddy, C.; Reddy, K.

    2006-01-01

    Natural radiation sources contribute the largest component to the total effective dose received by the human population. Among these sources, natural background gamma radiation shares a noteworthy amount. The present study aims at the establishment of baseline environmental gamma radiation data in the environs of proposed uranium mining areas of Andhra Pradesh, India. To this end, a systematic study has been undertaken using Thermoluminescence (T.L.) dosimeters and G.M. (Geiger - Muller) tube based survey meter. These levels are estimated both indoors and outdoors in the study area covering about 23 villages surrounding the proposed mining sites. The estimated external gamma radiation levels (air kerma) varied from 0.605 to 4.39 mGy.y -1 . The mean indoor to outdoor radiation level ratio is found to be 1.1 ± 0.1. The estimated mean equivalent doses due to external background radiation in the villages of the study area range from 1.03 to 2.83 mSv.y -1 with a mean of 2.34 ± 0.39 mSv.y -1 . (authors)

  5. Using RADFET for the real-time measurement of gamma radiation dose rate

    Science.gov (United States)

    Andjelković, Marko S.; Ristić, Goran S.; Jakšić, Aleksandar B.

    2015-02-01

    RADFETs (RADiation sensitive Field Effect Transistors) are integrating ionizing radiation dosimeters operating on the principle of conversion of radiation-induced threshold voltage shift into absorbed dose. However, one of the major drawbacks of RADFETs is the inability to provide the information on the dose rate in real-time using the conventional absorbed dose measurement technique. The real-time monitoring of dose rate and absorbed dose can be achieved with the current mode dosimeters such as PN and PIN diodes/photodiodes, but these dosimeters have some limitations as absorbed dose meters and hence they are often not a suitable replacement for RADFETs. In that sense, this paper investigates the possibility of using the RADFET as a real-time dose rate meter so that it could be applied for simultaneous online measurement of the dose rate and absorbed dose. A RADFET sample, manufactured by Tyndall National Institute, Cork, Ireland, was tested as a dose rate meter under gamma irradiation from a Co-60 source. The RADFET was configured as a PN junction, such that the drain, gate and source terminals were grounded, while the radiation-induced current was measured at the bulk terminal, whereby the bulk was successively biased with 0 , 10 , 20  and 30 V. In zero-bias mode the radiation-induced current was unstable, but in the biased mode the current response was stable for the investigated dose rates from 0.65  to 32.1 Gy h-1 and up to the total absorbed dose of 25 Gy. The current increased with the dose rate in accordance with the power law, whereas the sensitivity of the current read-out was linear with respect to the applied bias voltage. Comparison with previously analyzed PIN photodiodes has shown that the investigated RADFET is competitive with PIN photodiodes as a gamma radiation dose rate meter and therefore has the potential to be employed for the real-time monitoring of the dose rate and absorbed dose.

  6. Using RADFET for the real-time measurement of gamma radiation dose rate

    International Nuclear Information System (INIS)

    Andjelković, Marko S; Ristić, Goran S; Jakšić, Aleksandar B

    2015-01-01

    RADFETs (RADiation sensitive Field Effect Transistors) are integrating ionizing radiation dosimeters operating on the principle of conversion of radiation-induced threshold voltage shift into absorbed dose. However, one of the major drawbacks of RADFETs is the inability to provide the information on the dose rate in real-time using the conventional absorbed dose measurement technique. The real-time monitoring of dose rate and absorbed dose can be achieved with the current mode dosimeters such as PN and PIN diodes/photodiodes, but these dosimeters have some limitations as absorbed dose meters and hence they are often not a suitable replacement for RADFETs. In that sense, this paper investigates the possibility of using the RADFET as a real-time dose rate meter so that it could be applied for simultaneous online measurement of the dose rate and absorbed dose. A RADFET sample, manufactured by Tyndall National Institute, Cork, Ireland, was tested as a dose rate meter under gamma irradiation from a Co-60 source. The RADFET was configured as a PN junction, such that the drain, gate and source terminals were grounded, while the radiation-induced current was measured at the bulk terminal, whereby the bulk was successively biased with 0 , 10 , 20  and 30 V. In zero-bias mode the radiation-induced current was unstable, but in the biased mode the current response was stable for the investigated dose rates from 0.65  to 32.1 Gy h −1 and up to the total absorbed dose of 25 Gy. The current increased with the dose rate in accordance with the power law, whereas the sensitivity of the current read-out was linear with respect to the applied bias voltage. Comparison with previously analyzed PIN photodiodes has shown that the investigated RADFET is competitive with PIN photodiodes as a gamma radiation dose rate meter and therefore has the potential to be employed for the real-time monitoring of the dose rate and absorbed dose. (paper)

  7. Effect of low-dose gamma-radiation upon hatchability and weight of chickens

    International Nuclear Information System (INIS)

    Vilic, M.; Kraljevic, P.; Simpraga, M.; Miljanic, S.

    2006-01-01

    Full text of publication follows: Although any dose of ionizing radiation has generally been recognized to be detrimental to living being, low dose ionizing radiation seems to invoke primary stimulative effects. Stimulatory effects of low dose ionizing radiation include many aspects such as growth, fecundity and longevity stimulation, accelerated development, enhance biological responses for immune systems, enzymatic repair, physiological functions, and the removal of cellular damage, including prevention and removal of cancers and other diseases. Low dose ionizing radiation might also cause changes in the concentration of some biochemical parameters in blood plasma of chickens such as changes in the concentration of total proteins, glucose and cholesterol. The objective of this study was to determine the effect of low doses of gamma irradiation before incubation and on the seventh day of incubation on hatchability of eggs and body weight of chickens. This study includes three independent experiments. In the first experiment, six-hundred eggs produced by a commercial flock of Avian-line 34, were irradiated by a dose of 0.15 Gy gamma radiation (60 Co) before incubation. In the second experiments also involving six-hundred-line 34 eggs were irradiated by dose of 0.15 Gy gamma radiation on the seventh day of incubation. In the third experiment three-hundred eggs produced by a commercial flock of Ross 308 were irradiated by dose 0.30 Gy gamma irradiation before incubation. Along with the chickens which were hatched from irradiated eggs, there was a control group of chickens hatched from nonirradiated eggs. All other conditions were the same for both groups. Hatchability was calculated in terms of all eggs divided with fertile eggs which hatched. The individual weights of the chickens were determined on the first and on the forty second day. Growth data were analyzed statistically by t-test. Irradiation of chicken eggs and embryos at rates o f 0.15 Gy increases

  8. Estimate on external effective doses received by the Iranian population from environmental gamma radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Roozitalab, J.; Reza deevband, M.; Rastkhah, N. [National Radiation Protection Dept. Atomic Energy Organization (Iran, Islamic Republic of); Sohrabi, M. [Intenatinal atomic Energy Agency, Vienna (Austria)

    2006-07-01

    Concentration of natural radioactive materials, especially available U 238, Ra 226, Th 232, and K 40 in construction materials and soil, as well as absorb dose from cosmic rays, is the most important source of the people for effective doses from the environment radiation. In order to evaluate external effective dose, it has been carried out more than 1000 measurements in 36 cities by sensitive dosimeters to environmental gamma radiation for indoor and outdoor conditions in residential areas; which its results show that range of gamma exposure for inside of buildings in Iran is 8.7-20.5 {mu}R/h, and outdoor environments of different cities is 7.9-20.6 {mu}R/h, which their mean value are 14.33 and 12.62 {mu}R/h respectively. Meanwhile, it has been estimated that beam-absorbing ratio between indoor and outdoor in measured environments is 1.55, except contribution of cosmic rays. This studies show that average effective dose for each Iranian person from environmental gamma is 96.9 n Sv/h, and annually effective dose for every person is 0.848 mSv. (authors)

  9. Estimate on external effective doses received by the Iranian population from environmental gamma radiation sources

    International Nuclear Information System (INIS)

    Roozitalab, J.; Reza deevband, M.; Rastkhah, N.; Sohrabi, M.

    2006-01-01

    Concentration of natural radioactive materials, especially available U 238, Ra 226, Th 232, and K 40 in construction materials and soil, as well as absorb dose from cosmic rays, is the most important source of the people for effective doses from the environment radiation. In order to evaluate external effective dose, it has been carried out more than 1000 measurements in 36 cities by sensitive dosimeters to environmental gamma radiation for indoor and outdoor conditions in residential areas; which its results show that range of gamma exposure for inside of buildings in Iran is 8.7-20.5 μR/h, and outdoor environments of different cities is 7.9-20.6 μR/h, which their mean value are 14.33 and 12.62 μR/h respectively. Meanwhile, it has been estimated that beam-absorbing ratio between indoor and outdoor in measured environments is 1.55, except contribution of cosmic rays. This studies show that average effective dose for each Iranian person from environmental gamma is 96.9 n Sv/h, and annually effective dose for every person is 0.848 mSv. (authors)

  10. Natural gamma-ray spectrometry as a tool for radiation dose and radon hazard modelling

    International Nuclear Information System (INIS)

    Verdoya, M.; Chiozzi, P.; De Felice, P.; Pasquale, V.; Bochiolo, M.; Genovesi, I.

    2009-01-01

    We reviewed the calibration procedures of gamma-ray spectrometry with particular emphasis to factors that affect accuracy, detection limits and background radiation in field measurements for dosimetric and radon potential mapping. Gamma-ray spectra were acquired in western Liguria (Italy). The energy windows investigated are centred on the photopeaks of 214 Bi (1.76 MeV), 208 Tl (2.62 MeV) and 40 K (1.46 MeV). The inferred absorbed dose rate and the radon flux are estimated to be lower than 60 nGy h -1 and 22 Bq m -2 h -1 , respectively.

  11. Effect of low dose gamma-radiation upon Newcastle disease virus antibody level in chicken

    International Nuclear Information System (INIS)

    Vilic, M.; Gottstein, Z.; Ciglar Grozdanic, I.; Matanovic, K.; Miljanic, S.; Mazija, H.; Kraljevic, P.

    2009-01-01

    The specific antibody response against Newcastle disease virus in the blood serum of chickens hatched from eggs exposed to low dose gamma-radiation was studied. Materials and methods: Two groups of eggs of commercial meat chicken lines were irradiated with the dose of 0.30 Gy 60 Co gamma-rays before incubation and on the 19 th day of incubation, respectively. The same number of eggs unexposed to gamma-radiation served as controls. After hatching the group of chicken hatched from eggs irradiated on the 19 th day of incubation was not vaccinated while the group of chicken hatched from eggs irradiated before incubation was vaccinated on the 14 day. Specific serum anti-Newcastle disease virus antibodies were quantified by the hemagglutination inhibition assay with 4 HA units of Newcastle disease virus La Sota strain. Result: Specific antibody titres against Newcastle disease virus in the blood serum of chickens hatched from eggs irradiated before incubation and vaccinated on the 14 th day significantly increased on the 28 th day. Specific antibody titre against Newcastle disease virus in the blood serum of chickens hatched from eggs irradiated on the 19 th day of incubation and non-vaccinated was significantly higher on the 1 st and 14 th day. Conclusion: Acute irradiation of heavy breeding chicken eggs with the dose of 0.30 Gy 60 Co gamma-rays before incubation and on the 19 th day of incubation could have a stimulative effect on humoral immunity in chickens.

  12. Determining lethal dose of gamma radiation on different stages of Tribolium Cosmonauts H b s t

    International Nuclear Information System (INIS)

    Zolfagharieh, H.R.; Majd, F.; Torshyzie, M.; Babaie, M.

    1992-10-01

    Pest infestation causes great losses to stored grain through out the world. This is specially true in developing countries where the technology is less advanced, and climatic conditions are extremely favourable for the development of pests. Irradiation is on approved method of direct control for stored-product insect in wheat and wheat flour in many countries, and in dictation are that it will soon be approved for all grain, grain products and other dry food commodities. Radiation doses required to kill or sterilized the most important storage pests in all stages are known. However irradiation is very effective in preventing insect development and in producing sterility. A detailed analysis of the radiosensitivity of stored-product insects shows the different groups of pests have very different sensitivities and quarantine doses can be tailored to kill or sterilize the species of quarantine concern. The effect of irradiation on insects are many, and varied, depending primarily on the species, stage, age and physical factors. The aim is to survey the effect of gamma radiation on stored pest, which can categorized under following classes: 1-The effect of gamma radiation on different stages grow of tribolium castaneum (H B S T); 2-Determination of lethal doses.; 3-The study of gamma radiation on products. In summary these information indicated that fairly low dosages of gamma radiation could be used on commodities such as bulk grain in which some infestation by insect stages of irradiation would be required on products such package foods where hundred percent mortality must be obtain. (author)

  13. Low doses effects and gamma radiations low dose rates; Les effets des faibles doses et des faibles debits de doses de rayons gamma

    Energy Technology Data Exchange (ETDEWEB)

    Averbeck, D [Institut Curie, CNRS UMR 2027, 75 - Paris (France)

    1999-07-01

    This expose wishes for bringing some definitions and base facts relative to the problematics of low doses effects and low dose rates effects. It shows some already used methods and some actual experimental approaches by focusing on the effects of ionizing radiations with a low linear energy transfer. (N.C.)

  14. Dose Response for Monokaryon mycelium of Pleurotus pulmonarius After Acute Gamma Radiation

    International Nuclear Information System (INIS)

    Wan Safina Wan Abdul Razak; Azhar Mohamad; Nie, H.J.

    2016-01-01

    Pleurotus pulmonarius is locally known as Grey oyster. The species is popular and widely cultivated throughout the world mostly in Asia Europe as their simple and low cost production technology and higher biological efficiency. Mutation induction is an alternative ways for improving available commercial strain for better quality traits. Dose response is important in evaluating effects of mutagenesis via acute gamma radiation. Monokaryon mycelium of Pleurotus pulmonarius was exposed to acute gamma radiation ranged from 0 Gy, 0.1 kGy, 0.2 kGy, 0.3 kGy, 0.4 kGy, 0.5 kGy, 0.6 kGy, 0.7 kGy, 0.8 kGy, 0.9 kGy, 1.0 kGy, 1.5 Gy, 2.0 kGy, 3.0 kGy and 4.0 kGy at dose rate 0.013 kGy/ min. growth performance was measured at 2 days interval to get the LD_5_0. Increasing of the irradiation dose found to decrease the growth performance of the monokaryon mycelium. LD_5_0 was revealed at 1.56 kGy for mono karyon mycelium. Discoveries of the works are important for the improvement of Pleurotus species via acute gamma radiation and benefiting to growers and mushroom industries. (author)

  15. Alkaline and Acid Phosphatase Activity in Blood Plasma of Chickens Irradiated by Low dose Gamma Radiation

    International Nuclear Information System (INIS)

    Petar, K.; Marinko, V.; Saveta, M.; Miljenko, S.

    2004-01-01

    In our previous paper (Kraljevic et, al, 2000; Kraljevic et al 2002) we showed that the growth of the chickens hatched from eggs irradiated with 0.15 Gy gamma-rays before incubation was significantly higher than in controls during the fattening period (1-42 days). The concentration of total protein, glucose and cholesterol in the blood plasma of the same chickens was also significantly changed. In this paper an attempt was made to determine the effect of irradiation of eggs by low dose ionizing radiation before incubation upon activity of alkaline and acid phosphatase in the blood plasma of chickens hatched from irradiated eggs. The eggs of heavy breeding chickens were irradiated by dose of 0.15 Gy gamma radiation (60 Co) before incubation. Along with the chickens which were hatched from irradiated eggs, there was a control group of chickens hatched from nonirradiated eggs. All other conditions were the same for both groups. After hatching, blood samples were taken from the wing vein on days 1, 3, 5, 6, 10, 20, 30 and 42. The activity of both enzymes was determined spectrophotometrically by using Boehring Mannheim GmbH optimized kits. the activity of alkaline phosphatase in blood plasma was decreased on days 42, and the activity of acid phosphatase in the blood plasma of the same chickens was increased on day 42. Obtained results confirm our early obtained results that low dose of gamma radiation has effects upon metabolic processes in the chickens hatched from eggs irradiated before incubation. (Author)

  16. Effect of dose and dose rate of gamma radiation on catalytic activity of catalase

    International Nuclear Information System (INIS)

    Vaclav Cuba; Tereza Pavelkova; Viliam Mucka

    2010-01-01

    Catalytic activity of gamma irradiated catalase from bovine liver was studied for hydrogen peroxide decomposition at constant temperature and pressure. The measurement was performed at temperatures 27, 32, 37, 42 and 47 deg C. Solutions containing 1 and 0.01 g dm -3 of catalase in phosphate buffer were used for the study. Repeatability of both sample preparation and kinetics measurement was experimentally verified. Rate constants of the reaction were determined for all temperatures and the activation energy was evaluated from Arrhenius plot. Gamma irradiation was performed using 60 Co radionuclide source Gammacell 220 at two different dose rates 5.5 and 70 Gy h -1 , with doses ranging from 10 to 1000 Gy. The observed reaction of irradiated and non-irradiated catalase with hydrogen peroxide is of the first order. Irradiation significantly decreases catalytic activity of catalase, but the activation energy does not depend markedly on the dose. The effect of irradiation is more significant at higher dose rate. (author)

  17. Verification by the FISH translocation assay of historic doses to Mayak workers from external gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Sotnik, Natalia V.; Azizova, Tamara V. [Southern Urals Biophysics Institute (SUBI), Ozyorsk, Chelyabinsk Region (Russian Federation); Darroudi, Firouz [Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands); College of North Atlantic, Department of Health Science, Centre for Human Safety and Environmental Research, Doha (Qatar); Ainsbury, Elizabeth A.; Moquet, Jayne E.; Lloyd, David C.; Hone, Pat A.; Edwards, Alan A. [Public Health England, Chilton, Oxfordshire (United Kingdom); Fomina, Janna [Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands)

    2015-11-15

    The aim of this study was to apply the fluorescence in situ hybridization (FISH) translocation assay in combination with chromosome painting of peripheral blood lymphocytes for retrospective biological dosimetry of Mayak nuclear power plant workers exposed chronically to external gamma radiation. These data were compared with physical dose estimates based on monitoring with badge dosimeters throughout each person's working life. Chromosome translocation yields for 94 workers of the Mayak production association were measured in three laboratories: Southern Urals Biophysics Institute, Leiden University Medical Center and the former Health Protection Agency of the UK (hereinafter Public Health England). The results of the study demonstrated that the FISH-based translocation assay in workers with prolonged (chronic) occupational gamma-ray exposure was a reliable biological dosimeter even many years after radiation exposure. Cytogenetic estimates of red bone marrow doses from external gamma rays were reasonably consistent with dose measurements based on film badge readings successfully validated in dosimetry system ''Doses-2005'' by FISH, within the bounds of the associated uncertainties. (orig.)

  18. Non-linear dose response of a few plant taxa to acute gamma radiation

    International Nuclear Information System (INIS)

    George, J.T.; Patel, B.B.; Pius, J.; Narula, B.; Shankhadarwar, S.; Rane, V.A.; Venu-Babu, P.; Eapen, S.; Singhal, R.K.

    2014-01-01

    Micronuclei induction serves as an essential biomarker of radiation stress in a living system, and the simplicity of its detection technique has made it a widely used indicator of radiation damage. The present study was conducted to reveal the cytological dose-response of a few plant taxa, viz., Allium cepa var. aggregatum Linn., Allium sativum Linn., Chlorophytum comosum (Thunb.) Jacques and Eichhornia crassipes (Mart.) Solms, to low LET gamma radiation with special emphasis on the pattern of micronuclei induced across low and high dose regimes. A tri-phasic non-linear dose-response pattern was observed in the four taxa studied, characterized by a low dose linear segment, a plateau and a high dose linear segment. Despite a similar response trend, the critical doses where the phase transitions occurred varied amongst the plant taxa, giving an indication to their relative radiosensitivities. E. crassipes and A. sativum, with their lower critical doses for slope modifications of phase transitions, were concluded as being more radiosensitive as compared to C. comosum and A. cepa, which had relatively higher critical doses. (author)

  19. Supplementary comparison CCRI(I)-S2 of standards for absorbed dose to water in 60Co gamma radiation at radiation processing dose levels

    DEFF Research Database (Denmark)

    Burns, D. T.; Allisy-Roberts, P. J.; Desrosiers, M. F.

    2011-01-01

    Eight national standards for absorbed dose to water in 60Co gamma radiation at the dose levels used in radiation processing have been compared over the range from 1 kGy to 30 kGy using the alanine dosimeters of the NIST and the NPL as the transfer dosimeters. The comparison was organized...... by the Bureau International des Poids et Mesures, who also participated at the lowest dose level using their radiotherapy-level standard for the same quantity. The national standards are in general agreement within the standard uncertainties, which are in the range from 1 to 2 parts in 102. Evidence of a dose...

  20. Lethal dose of gamma radiation for eggs of Corcyra cephalonica (Stainton, 1865) (Lepidoptera: Pyralidae), rice moth

    International Nuclear Information System (INIS)

    Aguilar, J.A.D.; Arthur, V.

    1994-01-01

    The aim of this experiment was to observe the effects of gamma radiation on rice moth Corcyra cephalonica (STAINTON, 1865) eggs. The doses utilized in this experiment were 0; 25; 50; 75; 100; 125; 150; 175; 200 Gy. The experiment was carried out in a climatic room at 25 ± 2 0 C and 70 ± 10% R.H. It was observed that lethal dose LD50 and LD100 for eggs from adults reared by artificial diet were 16 and 75 Gy, respectively. (author). 14 refs, 1 fig, 1 tab

  1. Effect of superlarge dose of gamma radiation on the rat cerebral cortex (ultrastructural aspects)

    International Nuclear Information System (INIS)

    Abdrakhmanov, A.A.; AN Kazakhskoj SSR, Alma-Ata

    1988-01-01

    Puberal Wistar line mall rats (180-210 g) were subjected to single whole-body gamma irradiation with 150 Gy dose and 75 Gy/min dose rate. Electron-microscopic investigation into dynamics of sensory-motor cortex ultrastructural changes during 24 hours after irradiation is conducted. Along with destructive changes compensator-reduction processes are developed in brain tissue at this period. Already during the first hours after irradiation the neutron ultrastructure change dynamics has been determined, alongside with direct radiation effect, by indirect effects juries of neuroglia and microcirculatory channel

  2. Effect of superlarge dose of gamma radiation on the rat cerebral cortex (ultrastructural aspects)

    Energy Technology Data Exchange (ETDEWEB)

    Abdrakhmanov, A A

    1988-06-01

    Puberal Wistar line mall rats (180-210 g) were subjected to single whole-body gamma irradiation with 150 Gy dose and 75 Gy/min dose rate. Electron-microscopic investigation into dynamics of sensory-motor cortex ultrastructural changes during 24 hours after irradiation is conducted. Along with destructive changes compensator-reduction processes are developed in brain tissue at this period. Already during the first hours after irradiation the neutron ultrastructure change dynamics has been determined, alongside with direct radiation effect, by indirect effects juries of neuroglia and microcirculatory channel.

  3. Gene expression in Catla catla (Hamilton) subjected to acute and protracted doses of gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Anbumani, S., E-mail: aquatox1982@gmail.com; Mohankumar, Mary N., E-mail: marynmk@gmail.com

    2016-09-15

    Highlights: • Gamma radiation induced up- and down- regulation of cell cycle genes. • Protracted dose-rate induced gene up-regulation to facilitate cell survival. • bcl-2 gene facilitates repair at protracted dose and cell death at acute exposures. • gadd45α, cdk1 and bcl-2 genes work in concert to promote ‘repair’ and ‘death’ circuitries in fish blood cells. - Abstract: Studies on transcriptional modulation after gamma radiation exposure in fish are limited. Cell cycle perturbations and expression of apoptotic genes were investigated in the fish, Catla catla after acute and protracted exposures to gamma radiation over a 90 day period. Significant changes in gene expression were observed between day 1 and 90 post-exposure. Gamma radiation induced a significant down-regulation of target genes gadd45α, cdk1 and bcl-2 from day 1 to day 3 after protracted exposure, whereas it persists till day 6 upon acute exposure. From day 12 onwards, Gadd45α, cdk1 and bcl-2 genes were up-regulated following protracted exposure, indicating DNA repair, cell-cycle arrest and apoptosis. There exists a linear correlation between these genes (gadd45α – r = 0.85, p = 0.0073; cdk1 – r = 0.86, p = 0.0053; bcl-2 – r = 0.89, p = 0.0026) at protracted exposures. This is the first report on the dual role of bcl-2 gene in fish exposed to acute and protracted radiation and correlation among the aforementioned genes that work in concert to promote ‘repair’ and ‘death’ circuitries in fish blood cells.

  4. Gene expression in Catla catla (Hamilton) subjected to acute and protracted doses of gamma radiation

    International Nuclear Information System (INIS)

    Anbumani, S.; Mohankumar, Mary N.

    2016-01-01

    Highlights: • Gamma radiation induced up- and down- regulation of cell cycle genes. • Protracted dose-rate induced gene up-regulation to facilitate cell survival. • bcl-2 gene facilitates repair at protracted dose and cell death at acute exposures. • gadd45α, cdk1 and bcl-2 genes work in concert to promote ‘repair’ and ‘death’ circuitries in fish blood cells. - Abstract: Studies on transcriptional modulation after gamma radiation exposure in fish are limited. Cell cycle perturbations and expression of apoptotic genes were investigated in the fish, Catla catla after acute and protracted exposures to gamma radiation over a 90 day period. Significant changes in gene expression were observed between day 1 and 90 post-exposure. Gamma radiation induced a significant down-regulation of target genes gadd45α, cdk1 and bcl-2 from day 1 to day 3 after protracted exposure, whereas it persists till day 6 upon acute exposure. From day 12 onwards, Gadd45α, cdk1 and bcl-2 genes were up-regulated following protracted exposure, indicating DNA repair, cell-cycle arrest and apoptosis. There exists a linear correlation between these genes (gadd45α – r = 0.85, p = 0.0073; cdk1 – r = 0.86, p = 0.0053; bcl-2 – r = 0.89, p = 0.0026) at protracted exposures. This is the first report on the dual role of bcl-2 gene in fish exposed to acute and protracted radiation and correlation among the aforementioned genes that work in concert to promote ‘repair’ and ‘death’ circuitries in fish blood cells.

  5. Real time monitoring automation of dose rate absorbed in air due to environmental gamma radiation

    International Nuclear Information System (INIS)

    Dominguez Ley, Orlando; Capote Ferrera, Eduardo; Carrazana Gonzalez, Jorge A.; Manzano de Armas, Jose F.; Alonso Abad, Dolores; Prendes Alonso, Miguel; Tomas Zerquera, Juan; Caveda Ramos, Celia A.; Kalber, Olof; Fabelo Bonet, Orlando; Montalvan Estrada, Adelmo; Cartas Aguila, Hector; Leyva Fernandez, Julio C.

    2005-01-01

    The Center of Radiation Protection and Hygiene (CPHR) as the head institution of the National Radiological Environmental Surveillance Network (RNVRA) has strengthened its detection and response capacity for a radiological emergency situation. The measurements of gamma dose rate at the main point of the RNVRA are obtained in real time and the CPHR receives the data coming from those points in a short time. To achieve the operability of the RNVRA it was necessary to complete the existent monitoring facilities using 4 automatic gamma probes, implementing in this way a real time measurement system. The software, GenitronProbe for obtaining the data automatically from the probe, Data Mail , for sending the data via e-mail, and Gamma Red , for receiving and processing the data in the head institution ,were developed

  6. Determination of the sterilizing gamma radiation dose of 60Co to ACANTHOSCELIDES OBTECTUS imagos (col. bruchidae)

    International Nuclear Information System (INIS)

    Arthur, V.; Wiendl, F.M.; Sgrillo, R.B.; Campanhola, C.

    1980-01-01

    This paper relates the results of experiments dealing with irradiation of adults of Acanthoscelides obtectus (Say, 1831). The insects were irradiated with doses of 0 (control), 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 20 krad gamma radiation of a 60 Co source. After irradiation, the adults were kept for observation on beans (Phaseolus vulgaris) var. Jalo, in a controlled environmen t chamber at 30 +- 1 0 C and 70 +- 5% relative humidity. Continuous weighing at weekly intervals was done 22 times, showing, by weight loss in percent, that the sterilizing dose for adults was 10,65 krad. It could also be observed that losses of less than 0,5% occured at 9 krad. For a possible employment on commercial scale, the ideal radiation dose for bean desinfestation would be 10 krad, after which no weight loss occurrence. (Author) [pt

  7. Terrestrial gamma radiation dose rate in Ryukyu Islands, subtropical region of Japan

    International Nuclear Information System (INIS)

    Furukawa, M.; Shiroma, M.; Motomura, D.; Fujioka, S.; Kawakami, T.; Yasuda, Y.; Arakawa, K.; Fukahori, K.; Jyunicho, M.; Ishikawa, S.; Ohomoto, T.; Kina, S.; Shiroma, Y.; Masuda, N.; Hiraoka, H.; Shingaki, R.; Akata, N.; Zhuo, W.; Tokonami, S.

    2015-01-01

    In order to explain the distribution of natural radiation level in the Asia, in situ measurements of dose rate in air due to terrestrial gamma radiation have been conducted in a total of 21 islands that belong to Ryukyu Islands (Ryukyu Archipelago), subtropical rejoin of southwest Japan. Car-borne surveys have also been carried out in Okinawa-jima, the biggest island of the archipelago. Based on the results for these measurements, arithmetic mean, the maximum and the minimum of the dose rates at 1 m in height from the unpaved soil ground in the archipelago were estimated to be 47, 165 and 8 nGy h -1 , respectively. A comparative study of car-borne data obtained prior to and subsequent to the 2011 Fukushima nuclear accident, as for Okinawa-jima, indicated that the nuclear accident has no impact on the environmental radiation at the present time. (authors)

  8. Influence of dose on particle size of colloidal silver nanoparticles synthesized by gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Naghavi, Kazem, E-mail: Kazem.naghavi@gmail.co [Universiti Putra Malaysia, Physics Department, 43400 UPM SERDANG, Selangor (Malaysia); Saion, Elias [Universiti Putra Malaysia, Physics Department, 43400 UPM SERDANG, Selangor (Malaysia); Rezaee, Khadijeh [Department of Nuclear Engineering, Faculty of Modern Sciences and Technologies, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Yunus, Wan Mahmood Mat [Universiti Putra Malaysia, Physics Department, 43400 UPM SERDANG, Selangor (Malaysia)

    2010-12-15

    Colloidal silver nanoparticles were synthesized by {gamma}-irradiation-induced reduction method of an aqueous solution containing silver nitrate as a precursor in various concentrations between 7.40x10{sup -4} and 1.84x10{sup -3} M, polyvinyl pyrrolidone for capping colloidal nanoparticles, isopropanol as radical scavenger of hydroxyl radicals and deionised water as a solvent. The irradiations were carried out in a {sup 60}Co {gamma} source chamber at doses up to 70 kGy. The optical absorption spectra were measured using UV-vis spectrophotometer and used to study the particle distribution and electronic structure of silver nanoparticles. As the radiation dose increases from 10 to 70 kGy, the absorption intensity increases with increasing dose. The absorption peak {lambda}{sub max} blue shifted from 410 to 403 nm correspond to the increase of absorption conduction electron energy from 3.02 to 3.08 eV, indicating the particle size decreases with increasing dose. The particle size was determined by photon cross correlation spectroscopy and the results showed that the particle diameter decreases exponentially with the increase of dose. The transmission electron microscopy images were taken at doses of 20 and 60 kGy and the results confirmed that as the dose increases the diameter of colloidal silver nanoparticle decreases and the particle distribution increases.

  9. Effect of sub-sterilizing doses of gamma radiation on Spodoptera frugiperda (Smith) pupae

    International Nuclear Information System (INIS)

    Duarte Aguilar, J.A.; Arthur, Valter

    1998-01-01

    Studies were undertaken to verify the effects of sub-sterilizing doses of gamma radiations on pupae of Spodoptera frugiperda (Smith) and transfer of genetic heredity on the first and second generations. Statistical analysis showed difference in the ageing effect of gamma radiations on the larval phase and larval viability ranged between 72 and 94 percent, when irradiated (50 Gy) males or females were crossed with non-irradiated adults. With doses of 100, 125, 150 and 175 Gy the crossing of irradiated males x non irradiated females the larval viability was between 64 and 94 per cent in F-1 and F-2 generations. The duration and other life parameters of the pupae and adults did not differ from the controls. The egg laying ability was not affected by doses up to 150 Gy on both the sexes. If irradiated females with doses of 175 and 200 Gy were crossed with non-irradiated males, the egg laying was inhibited when males were irradiated with one of these doses, the offspring females did not lay eggs or laid non-fertile eggs. (author)

  10. Novel Concrete Chemistry Achieved with Low Dose Gamma Radiation Curing and Resistance to Neutron Activation

    Science.gov (United States)

    Burnham, Steven Robert

    As much as 50% of ageing-related problems with concrete structures can be attributed to con-struction deficiencies at the time of placement. The most influential time affecting longevity of concrete structures is the curing phase, or commonly the initial 28 days following its placement. A novel advanced atomistic analysis of novel concrete chemistry is presented in this dissertation with the objective to improve concrete structural properties and its longevity. Based on experiments and computational models, this novel concrete chemistry is discussed in two cases: (a) concrete chemistry changes when exposed to low-dose gamma radiation in its early curing stage, thus improving its strength in a shorter period of time then curing for the conventional 28 days; (b) concrete chemistry is controlled by its atomistic components to assure strength is not reduced but that its activation due to long-term exposure to neutron flux in nuclear power plants is negligible. High dose gamma radiation is well documented as a degradation mechanism that decreases concrete's compressive strength; however, the effects of low-dose gamma radiation on the initial curing phase of concrete, having never been studied before, proved its compressive strength increases. Using a 137 Cs source, concrete samples were subjected to gamma radiation during the initial curing phase for seven, 14, and 28 days. The compressive strength after seven days is improved for gamma cured concrete by 24% and after 14 days by 76%. Concrete shows no improvement in compressive strength after 28 days of exposure to gamma radiation, showing that there is a threshold effect. Scanning Electron Microscopy is used to examine the microstructure of low-dose gamma radiation where no damage to its microstructure is found, showing no difference between gamma cured and conventionally cured concrete. Molecular dynamics modeling based on the MOPAC package is used to study how gamma radiation during the curing stage improves

  11. EPR response of sucrose and microcrystalline cellulose to measure high doses of gamma radiation

    International Nuclear Information System (INIS)

    Torijano, E.; Cruz, L.; Gutierrez, G.; Azorin, J.; Aguirre, F.; Cruz Z, E.

    2015-10-01

    Solid dosimeters of sucrose and microcrystalline cellulose (Avicel Ph-102) were prepared, following the same process, in order to compare their EPR response against that of the l-alanine dosimeters considered as reference. All lots of dosimeters were irradiated with gamma radiation in Gamma beam irradiator with 8 kGy/h of the Nuclear Sciences Institute of UNAM. Doses ranged from 1 to 10 kGy respectively. We found that both the response of sucrose as microcrystalline cellulose were linear; however, the response intensity was, on average, twenty times more for sucrose. Comparing this against the EPR response of l-alanine in the range of doses, it was found that the response to sucrose is a third part; and microcrystalline cellulose is a sixtieth, approximately. The results agree with those found in the literature for sucrose, leaving open the possibility of investigating other dosage ranges for cellulose. (Author)

  12. Effects of low-dose gamma and neutron radiation on genotoxicity and cytotoxicity of reticulocytes in a mouse model

    International Nuclear Information System (INIS)

    Phan, N.; McFarlane, N.M.; Lemon, J.; Boreham, D.R.

    2008-01-01

    Using a successful new automation of micronucleated reticulocyte (MN-RET) scoring, the effects of low-dose (< 1.0 Gy) gamma and neutron radiation on genotoxicity and cytotoxicity of reticulocytes (RET) in a mouse model were investigated. Gamma and neutron irradiation induced significant (p<0.001) increases in the levels of %MN-RET and decreases in the levels of %RET (p<0.001) as the dose level increased. Increasing dose levels showed that gamma radiation induced significantly (p<0.05) more %MN-RET and more %RET than neutron radiation. The results suggest that neutron irradiation may be more cytotoxic (less %RET) than gamma irradiation; however, gamma irradiation may be producing cells with more chromosomal aberrations (more %MN-RET) than neutron irradiation. (author)

  13. Effects of low-dose gamma and neutron radiation on genotoxicity and cytotoxicity of reticulocytes in a mouse model

    Energy Technology Data Exchange (ETDEWEB)

    Phan, N.; McFarlane, N.M.; Lemon, J.; Boreham, D.R. [McMaster Univ., Medical Physics and Applied Radiation Sciences Unit, Hamilton, Ontario (Canada)

    2008-07-01

    Using a successful new automation of micronucleated reticulocyte (MN-RET) scoring, the effects of low-dose (< 1.0 Gy) gamma and neutron radiation on genotoxicity and cytotoxicity of reticulocytes (RET) in a mouse model were investigated. Gamma and neutron irradiation induced significant (p<0.001) increases in the levels of %MN-RET and decreases in the levels of %RET (p<0.001) as the dose level increased. Increasing dose levels showed that gamma radiation induced significantly (p<0.05) more %MN-RET and more %RET than neutron radiation. The results suggest that neutron irradiation may be more cytotoxic (less %RET) than gamma irradiation; however, gamma irradiation may be producing cells with more chromosomal aberrations (more %MN-RET) than neutron irradiation. (author)

  14. Effect of low-dose gamma radiation on HIV replication in human peripheral blood mononuclear cells

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y. [British Columbia Centre for Excellence in HIV/AIDS, British Columbia (Canada); Conway, B. [British Columbia Centre for Excellence in HIV/AIDS, British Columbia (Canada)]|[British Columbia Centre for Excellence in HIV/AIDS, British Columbia (Canada). Dept. of Medicine; Montaner, J.S.G. [British Columbia Centre for Excellence in HIV/AIDS, British Columbia (Canada)]|[British Columbia Centre for Excellence in HIV/AIDS, British Columbia (Canada). Dept. of Medicine]|[Canadian HIV Trials Network, Vancouver (Canada); O`Shaughnessy, M.V. [British Columbia Centre for Excellence in HIV/AIDS, British Columbia (Canada)]|[British Columbia Centre for Excellence in HIV/AIDS, British Columbia (Canada). Faculty of Medicine]|[Canadian HIV Trials Network, Vancouver (Canada); Greenstock, C.L. [AECL Research, Chalk River, Ontario (Canada). Radiation Biology and Health Physics Branch

    1996-08-01

    Recent studies have demonstrated that UV light and x-irradiation enhance human immunodeficiency virus (HIV) gene expression. There are few published data on related effects of {gamma}-radiation. This may be of clinical relevance, as radiotherapy has been used extensively for the treatment of acquired immunodeficiency syndrome associated conditions. We have studied the effects of {gamma}-radiation on HIV replication in mono-nuclear cells (MC). These cells were obtained from five seronegative healthy donors, exposed to 0-200 cGy {gamma}-radiation, stimulated with phytohemagglutinin-P (PHA-P) for 24 h, infected with a laboratory strain of HIV (HTLV-IIIB, multiplicity of infection = 0.001), then carried in culture for 14 days. Overall, when considering p24 antigen levels on days 7 and 11 in cultures established from cells exposed to 50 cGy, the maximal levels were significantly higher than those measured in the parallel control cultures taken as a whole (P < 0.05), with viral replication enhanced as much as 1000-fold in one case. No significant cytotoxicity was observed following exposure to doses up to 50 cGy. The mechanism of the observed effect remains unknown but may relate to direct gene activation and/or free radical generation, leading to such activation. To date, there is no evidence that viral stimulation occurs following therapeutic radiation in a clinical setting. (author).

  15. Effect of Low Dose Gamma Radiation on Some Biochemical Indicators in the Blood Plasma of Chickens

    International Nuclear Information System (INIS)

    Kraljevic, P.; Simpraga, M.; Vilic, M.; Miljanic, S.

    2001-01-01

    Full text: An attempt was made to determine the effect of irradiation of eggs by low dose ionising radiation before incubation on concentration of total protein, glucose and cholesterol in the blood plasma of chickens hatched from irradiated eggs. The eggs of heavy breeding chickens were irradiated by dose of 0.15 Gy gamma radiation ( 60 Co) before incubation. Along with the chickens which were hatched from irradiated eggs, there was the control group of chickens hatched from nonirradiated eggs. All other conditions were the same for the both groups. After hatching, blood samples were taken from the wing vein on days 1, 3, 5, 7, 10, 20, 30 and 42. The concentration of all three parameters was determined spectrophotometrically using Boehringer Mannheim GmbH optimized kits. The concentration of total protein was significantly decreased in the blood plasma of chickens hatched from irradiated eggs on days 3, 7 and 30 and increased only on day 5. The concentration of glucose in the blood plasma was increased in the same chickens on days 1 and 30. The concentration of the cholesterol was decreased in the same chickens on day 7, and increased on day 10. Obtained results indicate that low-dose of gamma radiation has effects on some metabolic processes in the chickens hatched from eggs irradiated before incubation. (author)

  16. Effect of low doses of gamma radiation on alfalfa (Lucerne) yield

    Energy Technology Data Exchange (ETDEWEB)

    Al-Odat, M; Khalifa, Kh [Atomic Energy Commission, Damascus (Syrian Arab Republic). Dept. of Radiation Agriculture

    1994-11-01

    Presowing seed irradiation has been reported frequently as a useful application of radiation in agriculture to stimulate growth and increase the yield of field and horticulture crops. Lucerne seeds of previous season (local variety) were irradiated by gamma rays Cs sup 1 sup 3 sup 7 source using doses of 5, 10, 15, 20, 30, and 40 Gy at dose rate of 9.2 Gy/min. Then were planted after 7 days from irradiation with unirradiated control in complete randomized block design and 5 replicates for three seasons (1986, 1987, 1988), the field experiment was carried out at ACSAD research station in Der-Ezzor. Also pot experiments were carried out to study the effect of low doses gamma irradiation on seed germination and growth of shoot and root systems of seedlings. The following observation were made on plants grown in the field:- fresh weight and dry weight of shoot system, - seed yield at the end of the experiment. The results show that there is a positive effect of seed irradiation on percentage of germination and root systems of seedling compared with the control. the highest increase in dry weight of shoot and root systems was at doses of 10 and 15 Gy. specially when sowing was 10 days after irradiation. Gamma irradiation doses of 10 and 15 Gy led to significant increases in fresh and dry weight at shoot system in the three seasons. The increases were 17.5% and 14.6% for the doses of 10 and 15 Gy respectively. A considerable increase in seed yield obtained at doses from 10 to 40 Gy, and the seed yield varied from 13.3% to 17.9% Compared with the control. (author). 20 refs., 18 tabs.

  17. Environmental gamma-ray dose measurements with thermoluminescence dosemeters (TLD) and environmental radiation characteristics

    International Nuclear Information System (INIS)

    Kanematsu, Seiko

    1999-01-01

    It is important to evaluate environmental gamma-ray exposure both at work and home in order to assess people's collective dosages. Environmental gamma radiation was measured for air-absorbed dose with a thermoluminescence dosemeter at various points in the workplace and Ningyotoge, and workplace radiation characteristics were analyzed. From the results, the public dose due to gamma rays generated artificially was assessed to be sufficiently lower than the annual limit. For indoor environments of the workplace, the maximum dosage rate among measured values was 97 nGy/h and the minimum value was 70 nGy/h, the average over one year was 83 nGy/h. The average annual outdoor dosage for a year was 82 nGy/ h. In Ningyotoge, the maximum was 103 nGy/h, minimum 60 nGy/h, and average 88 nGy/h. These values depend on the nature of the soil and weather factors, showing higher values in the summer than in the winter in the workplace. There was no significant difference in the dosage rate in houses and the workplace. (author)

  18. Low rate doses effects of gamma radiation on glycoproteins of transmembrane junctions in fibroblasts

    International Nuclear Information System (INIS)

    Bringas, J.E.; Caceres, J.L.

    1996-01-01

    Glycoproteins of trans-membrane junctions are molecules that help to bind cells with the extracellular matrix. Integrins are the most important trans-membrane molecules among others. The damage of gamma radiation on those proteins could be an important early event that causes membrane abnormalities which may lead to cell malfunction and cancer induced by radiation due to cell dissociation. Randomized blocks with 3 repetitions of mouse embryo fibroblast cultures, were irradiated with Cobalt-60 gamma rays, during 20 days. Biological damage to glycoproteins and integrins was evaluated by cellular growth and fibroblast proliferative capacity. Integrins damage was studied by isolation by column immunoaffinity chromatography migrated on SDS-Page under reducing and non reducing conditions, and inhibition of integrins extracellular matrix adhesion by monoclonal antibodies effect. The dose/rate (0.05 Gy/day-0.2 Gy/day) of gamma given to cells did not show damage evidence on glycoproteins and integrins. If damage happened, it was repaired by cells very soon, was delayed by continuous cellular division or by glycoproteins characteristic of being multiple extracellular ligatures. Bio effects became more evident with an irradiation time greater than 20 days or a high dose/rate. (authors). 6 refs

  19. Quantification of micronuclei in blood lymphocytes of patients exposed to gamma radiation for dose absorbed assessment

    International Nuclear Information System (INIS)

    Barbosa, Isvania Maria Serafim da Silva

    2003-02-01

    Dose assessment in an important step to evaluate biological effects as a result of individual exposure to ionizing radiation. The use of cytogenetic dosimetry based on the quantification of micronuclei in lymphocytes is very important to complement physical dosimetry, since the measurement of absorbed dose cannot be always performed. In this research, the quantification of micronuclei was carried out in order to evaluate absorbed dose as a result of radiotherapy with 60 Co, using peripheral blood samples from 5 patients with cervical uterine cancer. For this purpose, an aliquot of whole blood from the individual patients was added in culture medium RPMI 1640 supplemented with fetal calf serum and phytohaemagglutinin. The culture was incubated for 44 hours. Henceforth, cytochalasin B was added to block the dividing lymphocytes in cytokinesis. The culture was returned to the incubator for further of 28 hours. Thus, cells were harvested, processed and analyzed. Values obtained considering micronuclei frequency after pelvis irradiation with absorption of 0,08 Gy and 1,8 Gy were, respectively, 0,0021 and 0,052. These results are in agreement with some recent researches that provided some standard values related to micronuclei frequency induced by gamma radiation exposure in different exposed areas for the human body. The results presented in this report emphasizes biological dosimetry as an important tool for dose assessment of either total or partial-body exposure to ionizing radiation, mainly in retrospective dose investigation. (author)

  20. Effect of low doses of gamma radiation of Co-60 (radio-hormesis) in tomato seeds

    International Nuclear Information System (INIS)

    Wiendl, Toni Andreas

    2010-01-01

    Tomato seeds of the Gladiador hybrid were exposed to gamma radiation of Co-60 with the following doses: 0; 2,5; 5; 7,5; 10; 12,5; 15 e 20 Gy. Analysis were performed on germination, seedlings height to cotyledon, seedling total height, seedling fresh and dry weight, plant height, stalk diameter at the root beginning, fresh and dry weight of the 5 th leaf, number of green fruits with diameter higher than 3 cm, number of green, half ripen and ripen fruits, total number of fruits, Brix and pH of fruits, average fruit weight and fruit total production. A variety of stimulation effects were observed on the different plant developing stages. The greatest stimulus for production was observed in the 10 Gy dose. The highest seedling average height and plant average height were observed for the 7,5 Gy dose. The biggest number of green fruits with diameter higher than 3 cm occurred for the 12,5 and 15 Gy treatments. Irradiation also stimulated a higher total number of fruits in all doses, having advantage the 10 Gy dose which produced 88% more fruits than control as well as 86% more weight production. The fruits pH acidified significantly in a dose of 12,5 Gy and higher. Production increased in all treatments comparing to control and the highest stimulus for production observed was for the 10, 12,5 and 15 Gy. The use of low gamma radiation doses of Co-60 applied as pre-sowing treatment in the seeds, efficiently stimulated the development of plants and the tomato production. (author)

  1. Gene expression profiles following high-dose exposure to gamma radiation in salmonella enterica serovar typhimurium

    International Nuclear Information System (INIS)

    Lim, Sang Yong; Jung, Sun Wook; Joe, Min Ho; Kim, Dong Ho

    2008-01-01

    Microarrays can measure the expression of thousands of genes to identify the changes in expression between different biological states. To survey the change of whole Salmonella genes after a relatively high dose of gamma radiation (1 kGy), transcriptome dynamics were examined in the cells by using DNA microarrays. At least 75 genes were induced and 89 genes were reduced two-fold or more after irradiation. Several genes located in pSLT plasmid, cyo operon, and Gifsy prophage were induced along with many genes encoding uncharacterized proteins.While, the expression of genes involved in the virulence of Salmonella as well as metabolic functions were decreased. Although the radiation response as a whole could not be illustrated by using DNA microarrays, the data suggest that the response to high dose of irradiation might be more complex than the SOS response

  2. Gene expression profiles following high-dose exposure to gamma radiation in salmonella enterica serovar typhimurium

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang Yong; Jung, Sun Wook; Joe, Min Ho; Kim, Dong Ho [Radiation Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2008-08-15

    Microarrays can measure the expression of thousands of genes to identify the changes in expression between different biological states. To survey the change of whole Salmonella genes after a relatively high dose of gamma radiation (1 kGy), transcriptome dynamics were examined in the cells by using DNA microarrays. At least 75 genes were induced and 89 genes were reduced two-fold or more after irradiation. Several genes located in pSLT plasmid, cyo operon, and Gifsy prophage were induced along with many genes encoding uncharacterized proteins.While, the expression of genes involved in the virulence of Salmonella as well as metabolic functions were decreased. Although the radiation response as a whole could not be illustrated by using DNA microarrays, the data suggest that the response to high dose of irradiation might be more complex than the SOS response.

  3. Protective and Therapeutic Role of Low Dose Gamma Radiation on Streptozotocin Induced Diabetes in Rats

    International Nuclear Information System (INIS)

    Mansour, H.H.; Hafez, H.F.; Shouman, S.A.

    2011-01-01

    Diabetes mellitus is a multi-factorial disease which is characterized by vascular and renal complication. This study was initiated to investigate the protective and the therapeutic effect of low dose of gamma radiation (LDR) on diabetic complications. A total of 30 adult male rats were divided into 5 groups: Group I: served as control and injected intraperitoneally with 0.2 ml of 0.1 mol/l citrate buffer (ph 4.5), group II: rats became diabetic via intraperitoneal injection with 60 mg/kg streptozotocin (STZ) dissolved in 0.2 ml of 0.1 mol/l citrate buffer (ph 4.5), group III irradiated rats (IRR): submitted to fractionated dose of whole body gamma rays; 0.25 Gy for 2 consecutive days (whole dose 0.5 Gy), group IV diabetic irradiated rats (STZ + IRR): rats became diabetic as group II then four weeks after diabetes induction (day 28), rats were submitted to 2 fractions of whole body gamma rays as in group III, and group V irradiated diabetic rats (IRR + STZ): rats were injected intraperitoneally with 0.2 ml of 0.1 mol/l citrate buffer then submitted to whole body gamma rays; 0.25 Gy for 2 consecutive days then one hour after the last IRR dose, rats were made diabetic as group II. In pre and post-irradiation of STZ rats, significant changes were observed in serum lipid profiles, hepatic and cardiac serum enzymes. Significant decrease in hepatic and cardiac malondialdehyde (MDA) and total nitrate/nitrite (NO(x)) levels, and significant increase in superoxide dismutase (SOD) and glutathione (GSH) levels were observed as compared to diabetic group. The study suggests that LDR may provide useful protective and therapeutic option in the reversal of oxidative stress induced in diabetic rats

  4. Adjustment of gamma radiation doses for sterilization of Egyptian surgical sutures

    International Nuclear Information System (INIS)

    Tawfik, Z.S.; Helmy, M.M.; Roushdy, H.M.

    1984-01-01

    The adjustment of gamma radiation doses for sterilization of catguts under local manufacturing conditions has been performed. Average total initial counts for aerobic and anaerobic bacteria per item were relatively low, in the range of 1000 counts for aerobic and 10 counts for anaerobic bacteria. The microfiora (aerobic bacteria) of the studied sutures were isolated and identified to be: Bacillus sp.; Micrococcus varians, Micrococcus roseus, and Staphylococcus. Each purified and identified isolate was exposed to gamma radiation both in liquid media (broth) and in the preservative in which the sutures were supplied by the company. The LD values of the most resistant microorganisms in both case of liquid media and preservative, were obtained to be around 5 KGy. Deliberately contaminated sterile sutures with each isolate and with mixture of isolates were studied. The sterilizing dose was obtained to be 20KGy for most heavily contaminated items (10 10 counts) irradiated both in saline and in preservative. This sterilizing dose was found to be dependent of the initial viable counts. This value was considered to be a safe value for radiosterilization of the studied sutures preserved in isopropyl alcohol, glycerin, and water (90:3.5:16)

  5. Electrical resistance behavior with gamma radiation dose in bulk carbon nanostrutured samples

    International Nuclear Information System (INIS)

    Lage, J.; Leyva, A.; Pinnera, I.; Desdin, L. F.; Abreu, Y.; Cruz, C. M.; Leyva, D.; Toledo, C.

    2013-01-01

    The aim of this paper is to study the effects of 60 Co gamma radiation on the electrical resistance and V-I characteristic of bulk carbon nano structured samples obtained by electric arc discharge in water method. Images of pristine samples obtained with scanning electron, and the results in graphical form of the electrical characterization of irradiated samples are presented in the text. It was observed that the electrical resistance vs. dose behavior shows an initial increment reaching the maximum at approximately 135 kGy, followed by a drop of the resistance values. These behaviors are associated with the progressive generation of radiation induced defects in the sample, whose number increases to reach saturation at 135 kGy. From this dose, defects could lead to cross-links between different nano structures present in the sample conducting to a gradually drop in electrical resistance. The measured V-I curves show that, increasing exposure to the 60 Co gamma radiation, the electrical properties of the studied samples transit from a semiconductor towards a predominantly metallic behavior. These results were compared with those obtained for a sample of graphite powder irradiated under the same conditions. (Author)

  6. Set of programs for determining exposure and dose rates from selected sources of gamma radiation

    International Nuclear Information System (INIS)

    Hep, J.; Kralovcova, E.; Smutny, V.; Valenta, V.

    1982-01-01

    The programs are described for the determination of exposure and dose rate of gamma radiation from point, surface, linear and volume sources with and without shielding. The computation is conducted using the classical method taking into consideration the buildup factor. For the computation of the buildup factor in heterogeneous shielding the Broder and Kitazuma formulas are used. Kitazuma's alpha coefficients were calculated recurrently using a new semi-empirical method. Taylor's approximation was used for the calculation of the buildup factor in a single layer

  7. Gamma Radiation Dose from Radionuclides in Soil Samples of Udagamandalam (Ooty) in India

    International Nuclear Information System (INIS)

    Selvasekarapandian, S.; Muguntha Manikandan, N.; Sivakumar, R.; Balasubramanian, S.; Venkatesan, T.; Meenakshisundram, V.; Ragunath, V.M.; Gajendran, V.

    1999-01-01

    The systematic study of background radiation and the distribution of radionuclides in the environment of Udagamandalam in Nilgiri District of Tamil Nadu has been made. Gamma spectrometric analysis of the soil samples of this area has been carried out. The measured gamma dose in air is in the range 31.6 nGy.h -1 - 221.1 nGy.h -1 with a mean value 121.8 nGy.h -1 . The average activities of the 232 Th series, 238 U series and 40 K in soil samples are 114.6 ± 52.5 Bq.kg -1 , 43.2 ± 23.2 Bq.kg -1 and 274.6 ± 86.7 Bq.kg -1 respectively. (author)

  8. Crystal growth and thermoluminescence response of NaZr2(PO4)3 at high gamma radiation doses

    International Nuclear Information System (INIS)

    Ordóñez-Regil, E.; Contreras-Ramírez, A.; Fernández-Valverde, S.M.; González-Martínez, P.R.; Carrasco-Ábrego, H.

    2013-01-01

    Graphical abstract: -- Highlights: •NaZr 2 (PO 4 ) 3 exposed to gamma doses of 10, 30 and 50 MGy. •Gamma radiation produced growth of the crystal size of the NZP. •Morphology changes were reversible by heating. •Linear relationship between the thermoluminescence and the applied gamma dose. •This property could be useful for high-level gamma dosimetry. -- Abstract: This work describes the synthesis and characterization of NaZr 2 (PO 4 ) 3 . The stability of this material under high doses of gamma radiation was investigated in the range of 10–50 MGy. Samples of unaltered and gamma irradiated NaZr 2 (PO 4 ) 3 were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and thermoluminescence. The results showed that while functional groups were not affected by the gamma irradiation, morphology changes were observed with increasing doses of gamma irradiation. The morphology of the non-irradiated compound is agglomerated flakes; however, irradiation at 10 MGy splits the flakes inducing the formation of well-defined cubes. Gamma irradiation induced the crystal size of the NaZr 2 (PO 4 ) 3 to grow. The heat treatment (973 K) of samples irradiated at 50 MGy resulted in the recovery of the original morphology. Furthermore, the thermoluminescence analysis of the irradiated compound is reported

  9. Gynogenesis with high doses of gamma radiation in tomatoes -Lycopersicum esculentum Mill. (L.)

    International Nuclear Information System (INIS)

    Dryanovska, O.A.

    1983-01-01

    The behaviour of male chromatin at the germination of gamma irradiated pollen from the stigma to the embrio sac in tomatoes was investigated in connection with the induced gynogenesis and the transfer of genetic information from one species to another. Two male-sterile longistil varieties of Deva and Hera were used as mothers, while mixed pollen from cultivated varieties and Lycopersicum peruvianum (L.) was irradiated at doses of 1, 5, 10 and 200 Kr with a dose rate of up to 1500 R/min. The experiment was carried out in 6 replications, with between 3 and 15 flowers for each variant and variety. The irradiated male chromatin of L. peruvianum remains in the pollen tube that has grown close to the embryo sac and stimulates the development of the embryo and endosperm. The absense of anthocyanin and the normal diploid chromosome count were the two markers for characterizing the plants obtained at high doses of gamma radiation as secondarily diploidized gynogenetic diplo-haploids during embryogenesis. It is assumed that the highly damaged male chromatin and the cytoplasm of the pollen tube retain their stimulating function under the influence of the high doses. A decisive role may be placed by certain fragments with genes from the male chromatin. The mitochondria which retain their respirative capacity and are promptly restored even after irradiation may have a stimmulating influence at the induced haploidy. The secondary diploidization normalizes the development of the organism of haploid origin and makes it possible to overcome the poor viability and the higher sterility. The genes responsible for the synthesis of anthocyanin in the irradiated male chromatin are restroyed by the high radiation doses, and this is the reason for the absence of anthocyanin in the diplo-haploid plants

  10. Assessment of absorbed dose rate from terrestrial gamma radiation in Red Sea State

    International Nuclear Information System (INIS)

    Abdalrahman, H. E. K.

    2012-09-01

    This study is primarily conducted to contribute in the overall strategic objective of producing Sudan radiation map which will include natural radiation levels and the resultant absorbed dose rate in air. The part covered by this study is the Red Sea State. Soil samples were collected from locations lie between latitudes 17.03 ° and the 20.18 ° N and longitudes 36.06 ° E during September 2007. Activity concentrations of the primordial radionuclides, 226 Ra, 232 Th, and 40 K in the samples were measured using gamma-ray spectrometry equipped with Nal (Tl) detector. Absorbed dose rates in air a height of 1 from the ground level and the corresponding annual effective doses were calculated from the measured activities using Dose Rate Conversion Factors (DRCFs). On the average, the activity concentrations were 19.22±13.13 Bq kg -1 ( 232 Th), 17.91±15.44 Bq kg -1 ( 226 Ra) and (507.13±161.67) Bq kg -1 for 40 K. The obtained results were found to be within the global values reported in the UNSCEAR publication for normal background areas with the exception of the samples taken from Arbaat area. The absorbed dose rate in air as calculated using UNSCEAR conversion factor averaged 40.93 n Gy h -1 which corresponds to annual effective dose of 50.23 μSvy -1 . The major contribution to the total absorbed dose rate comes from 40 K, which amounts to 53.36%. Using Geographical Information System (GIS), predication maps for activity concentrations levels of the measured radionuclides in the Red Sea state was prepared to show their respective spatial distributions. Similarly, GIS predictive map was produced for annual effective dose.(Author)

  11. Effect of low doses of gamma radiation on barley's (Hordeum Vulgare L.) susceptibility to cochliobolus sativus

    International Nuclear Information System (INIS)

    Jawher, M.; Arabi, I. E.

    1998-03-01

    Two barley genotypes (Tadmor, W12291), and one promising line selected in AECS (76) were exposed to 60 cobalt gamma radiation. The doses used were: 0, 10, 15, 20, 30, 40 and 50 Gy. Susceptibility assessments were scored using a rating scale extending from 1 (highly resistant) to 5 (very susceptible) according to the percentage of infected area at subcrown interodes. In general, doses of 10, 15, 20 and 30 Gy increased the resistance to the pathogen Cochliobolus sativus by 56.29%, 58.29%, 54.57% and 49.71% respectively. The genotypes did not response similarly to the irradiation. The best response was obtained with c.v Tadmor. (author)

  12. Effects of low doses of gamma radiation on DNA synthesis in the developing rat brain

    International Nuclear Information System (INIS)

    Cerda, H.

    1983-01-01

    Rats of one or ten days of age were irradiated with low doses of gamma radiation, and synthesis of DNA was examined by the incorporation of 3 H-thymidine in the cerebellum and the rest of the brain in vivo. DNA synthesis was depressed in both parts of the brain but the effects were larger in cerebellum. A minimum was found about 10 hours after irradiation in the older rats and later (18 h) in the younger ones. The dose response in 10 day-old rats, was biphasic and showed that cerebellum was more affected. Autoradiographs showed that fewer cells entered the cycle and those synthesizing showed a depressed rate of synthesis. These findings are discussed in relation to induction of cell death. (Auth.)

  13. Dosimetric evaluation of lithium carbonate (Li2CO3) as a dosemeter for gamma-radiation dose measurements.

    Science.gov (United States)

    Popoca, R; Ureña-Núñez, F

    2009-06-01

    This work reports the possibility of using lithium carbonate as a dosimetric material for gamma-radiation measurements. Carboxi-radical ions, CO(2)(-) and CO(3)(-), arise from the gamma irradiation of Li(2)CO(3), and these radical ions can be quantified by electron paramagnetic resonance (EPR) spectrometry. The EPR-signal response of gamma-irradiated lithium carbonate has been investigated to determine some dosimetric characteristics such as: peak-to-peak signal intensity versus gamma dose received, zero-dose response, signal fading, signal repeatability, batch homogeneity, dose rate effect and stability at different environmental conditions. Using the conventional peak-to-peak method of stable ion radicals, it is concluded that lithium carbonate could be used as a gamma dosemeter in the range of 3-100 Gy.

  14. Dependence of malformation upon gestational age and exposed dose of gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung-Ho; Lee, Jong-Hwan; Oh, Heon; Kim, Se-Ra [Chonnam National Univ., Kwangju (Korea, Republic of). Coll. of Veterinary Medicine; Lee, Cha-Soo; Jo, Sung-Kee; Kim, Tae-Hwan; Lee, Yun-Sil

    2001-09-01

    In order to evaluate the importance of gestational age and the dose-incidence relationship by gamma radiation, pregnant ICR mice at gestational days from 2.5 to 15.5 days post-coitus (p.c.) were exposed to a single dose of 2.0 Gy and also at day 11.5 after conception, which was the most sensitive stage for the induction of major congenital malformations. The animals were sacrificed on day 18 of gestation and the fetuses were examined for mortality, growth retardation, changes in head size and other morphological abnormalities. The only demonstrable effect of irradiation during the pre-implantation period was an increase in prenatal mortality. Resorptions were maximal on exposure at day 2.5 after conception. The pre-implantation irradiated embryos which survived did not show any major fetal abnormalities. A small head, growth retardation, a cleft palate, dilatation of the cerebral ventricle, a renal pelvis, and abnormalities of the extremities and tail after exposure were prominent during the organogenesis period, especially on day 11.5 of gestation. As for the dose-incidence relationship, the incidence of a small head, growth-retarded fetuses, a cleft palate, dilatation of cerebral ventricle and abnormalities of the extremities in live fetuses rose as the radiation dose increased. The result indicated that the late period of organogenesis in the development of the brain, skull and extremities of a mouse was a particularly sensitive phase. The threshold doses of radiation that induced a cleft palate and dilatation of the cerebral ventricle, and abnormal extremities were between 1.0 and 2.0 Gy, and between 0.5 and 1.0 Gy, respectively. (author)

  15. Dependence of malformation upon gestational age and exposed dose of gamma radiation

    International Nuclear Information System (INIS)

    Kim, Sung-Ho; Lee, Jong-Hwan; Oh, Heon; Kim, Se-Ra; Lee, Cha-Soo; Jo, Sung-Kee; Kim, Tae-Hwan; Lee, Yun-Sil

    2001-01-01

    In order to evaluate the importance of gestational age and the dose-incidence relationship by gamma radiation, pregnant ICR mice at gestational days from 2.5 to 15.5 days post-coitus (p.c.) were exposed to a single dose of 2.0 Gy and also at day 11.5 after conception, which was the most sensitive stage for the induction of major congenital malformations. The animals were sacrificed on day 18 of gestation and the fetuses were examined for mortality, growth retardation, changes in head size and other morphological abnormalities. The only demonstrable effect of irradiation during the pre-implantation period was an increase in prenatal mortality. Resorptions were maximal on exposure at day 2.5 after conception. The pre-implantation irradiated embryos which survived did not show any major fetal abnormalities. A small head, growth retardation, a cleft palate, dilatation of the cerebral ventricle, a renal pelvis, and abnormalities of the extremities and tail after exposure were prominent during the organogenesis period, especially on day 11.5 of gestation. As for the dose-incidence relationship, the incidence of a small head, growth-retarded fetuses, a cleft palate, dilatation of cerebral ventricle and abnormalities of the extremities in live fetuses rose as the radiation dose increased. The result indicated that the late period of organogenesis in the development of the brain, skull and extremities of a mouse was a particularly sensitive phase. The threshold doses of radiation that induced a cleft palate and dilatation of the cerebral ventricle, and abnormal extremities were between 1.0 and 2.0 Gy, and between 0.5 and 1.0 Gy, respectively. (author)

  16. Degradation of polylactic acid (Pla) at different doses of gamma radiation

    International Nuclear Information System (INIS)

    Castillo R, Y.

    2015-01-01

    The excessive use of polymers such as polyethylene (PET), polystyrene (Ps) and recently the polylactic acid (Pla) that take more than 20 years to degrade, have caused great pollution in the environment. In this study the effects of gamma radiation in the Pla to different doses were studied, in order to reduce the degradation time of this polymer. The changes in physico-chemical structure of Pla during radiation were studied by thermo-gravimetric/Mass analysis; differential scanning calorimetry; scanning electron microscopy; X-ray dispersive analysis; infrared spectroscopy; X-ray diffraction and mechanical tests of hardness, elasticity and deformation. With scanning electron microscopy, the morphology of the Pla surface unirradiated was observed, in which an apparently smooth surface was observed, after changes that had the Pla when irradiated also was observed, where the effects of radiation were observed in form of scratch, agglomeration and small fractures. By X-ray dispersive analysis was determined and verified the elemental chemical composition of the Pla; as expected the tests showed only carbon, oxygen and hydrogen. With thermo-gravimetric/Mass analysis the decomposition temperatures of Pla were determined, identifying that the degradation compounds are CO, CO 2 and CH 4 . With infrared spectrometry the major peaks of Pla were observed before and after being irradiated with increasing of radiation dose the intensity of the bands decreased. Also by X-ray diffraction was observed that the polymer is an amorphous material. The mechanical tests indicate that the values of each of the tests decrease significantly with increasing the radiation dose. (Author)

  17. Environmental radiation monitoring: mobile gamma dose rate measurements along Mumbai-Hyderabad rail route and Hyderabad city roads

    International Nuclear Information System (INIS)

    Divkar, J.K.; Padmanabhan, N.; Chaudhury, Probal; Pradeepkumar, K.S.; Pujari, R.N.; Dogra, Santosh; Sharma, D.N.; Rajagopalan, S.; Srivastava, G.K.

    2005-01-01

    Environmental Radiation monitoring based on gamma dose rate logging on a mobile platform integrated with real time position from a Global Positioning System is an effective tool to acquire dose rate profile and generate radiological map of any geographical region. The microcontroller based dose rate data acquisition system capable of storing the acquired data and transferring to an attached laptop/PC and providing a graphical illustration of relative variations in gamma background can also be used for quick assessment of environmental radiological impact assessment. This paper describes the methodology and results of the environmental gamma dose rate monitoring surveys carried out: (i) on Mumbai-Hyderabad rail route with the systems installed in the trains guard's room and (ii) Hyderabad city roads with systems installed in a monitoring van. The results indicate significant difference in the gamma background measured along the rail route between Mumbai-Hyderabad and in the radiological map generated after the Hyderabad city survey. (author)

  18. Characterization of aqueous rose bengal dye solution for the measurement of low doses of gamma radiation

    International Nuclear Information System (INIS)

    Hasan Mahmood Khan; Khan, A.A.

    2010-01-01

    Aqueous solution of rose bengal dye has been studied spectrophotometrically as a gamma-ray dosimeter for the measurement of low doses of radiation. The useful dose range was found to be from 50 to 1000 Gy when the measurements were made at 549 nm. The effects of temperature and light conditions on the stability of response during post-irradiation storage were also investigated. When stored in dark at room temperature, the dosimetric solutions showed a stable response up to 22 days. The storage of irradiated solutions in diffused sunlight showed a stable response only up to 6 days. When exposed to direct sunlight, very prominent and fast bleaching of dye solution occurred. At low storage temperature (ca. 11 deg C), dosimetric response was found to be stable up to 22 days while at higher temperature (ca. 30 deg C), the response of dosimetric solution was stable only up to 6 days. The rose bengal aqueous solution showed promising characteristics as a low dose radiation dosimeter when stored at lower temperatures (<25 deg C) in dark. (author)

  19. Low doses of gamma radiation in the management of postharvest Lasiodiplodia theobromae in mangos

    Directory of Open Access Journals (Sweden)

    Alice Maria Gonçalves Santos

    2015-09-01

    Full Text Available The postharvest life of mango is limited by the development of pathogens, especially fungi that cause rot, among which stands out the Lasiodiplodia theobromae. Several control methods have been employed to minimize the damages caused by this fungus, chemical control can leave residues to man and nature; physical control by the use of gamma radiation in combination with modified atmosphere and cold storage. The use of gamma radiation helps to reduce the severity of the pathogen assist in the ripening process of fruits, even at low doses (0.25, 0.35 and 0.45 kGy chemical properties such as pH, soluble solids, acid ascorbic, titratable acidity and also the quality parameters of the pulp showed no damage that are ideal for trade and consumption of mangoes. This treatment can be extended for use in the management of diseases such as natural infections for penducular rot complex that has as one of L. theobroma pathogens involved.

  20. Adaptive response of yeast cultures (Saccharomyces Cerevisiae) exposed to low dose of gamma radiation

    International Nuclear Information System (INIS)

    Kulcsar, Agnes; Savu, D.; Petcu, I.; Gherasim, Raluca

    2003-01-01

    The present study was planned as follows: (i) setting up of standard experimental conditions for investigation of radio-induced adaptive response in lower Eucaryotes; (ii) developing of procedures for synchronizing Saccharomyces cerevisiae X 310 D cell cultures and cell cycle stages monitoring; (iii) investigation of gamma (Co-60) and UV irradiation effects on the viability of synchronized and non-synchronized cell cultures of Saccharomyces cerevisiae; the effects were correlated with the cell density and cell cycle stage; (iv) study of the adaptive response induced by irradiation and setting up of the experimental conditions for which this response is optimized. The irradiations were performed by using a Co-60 with doses of 10 2 - 10 4 Gy and dose rates ranging from 2.2 x 10 2 Gy/h to 8.7 x 10 3 Gy/h. The study of radioinduced adaptive response was performed by applying a pre-irradiation treatment of 100-500 Gy, followed by challenge doses of 2-4 kGy delivered at different time intervals, ranging from 1 h to 4 h. The survival rate of synchronized and non-synchronized cultures as a function of exposure dose shows an exponential decay shape. No difference in viability of the cells occurred between synchronized and non-synchronized cultures. The pre-irradiation of cells with 100 and 200 Gy were most efficient to induce an adaptive response for the yeast cells. In this stage of work we proved the occurrence of the adaptive response in the case of synchronized yeast cultures exposed to gamma radiation. The results will be used in the future to investigate the dependence of this response on the cell cycle and the possibility to induce such a response by a low level electromagnetic field. (authors)

  1. Determination of gamma radiation lethal dose (LD50) and resveratrol cytotoxicity level in tumor cells line

    International Nuclear Information System (INIS)

    Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R.; Cruz, Aurea S.

    2011-01-01

    Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD 50 ) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC 50% in NCI-H292 cells was 192μM and in RD cells was 128μM; and RD cells gamma radiation LD 50 was 435Gy. (author)

  2. Assessment of terrestrial gamma radiation dose rate (TGRD) of Kelantan State, Malaysia. Relationship between the geological formation and soil type to radiation dose rate

    International Nuclear Information System (INIS)

    Garba, N.N.; Gabdo, H.T.; Federal College of Education, Yola

    2014-01-01

    Terrestrial gamma radiation dose rates (TGRD) of Kelantan State were measured in situ using a portable [NaI(TI)] micro roentgen (μR) survey meter. The TGRD rates ranged between 44 and 500 nGy h -1 with a mean value of 209 ± 8 nGy h -1 . The distribution of these measurements in various districts of the state shows the statistically the influence of geology and soil types on the dose rate values. The data obtained could be used in formulating safety standard and radiological guidelines. (author)

  3. Petrography, Gamma Radiation Measurements and Dose Rate, Northeastern Um Ara Area, South Eastern Desert, Egypt

    International Nuclear Information System (INIS)

    Moghazy, N.M.

    2016-01-01

    The northern part of Um Ara alkali feldspar micro granite has subjected to extensive post-magmatic metasomatic reworking resulting in development of amazonitized and albitized zones, reflecting K- and Na metasomatism leading to gross enrichment in U and Th towards the more evolved phases (e.g., albitized zones). Spectrometric survey data indicate that eU in Dokhan volcanics has the range of 2 to 42 ppm with an average value of 10 ppm and in monzogranites. It varies from 3 to 13 ppm with an average of 7 ppm while in alkali feldspar microgranites eU contents vary from 3 to 282 ppm with an average value of 30 ppm. The (eTh) contents in Dokhan volcanics ranges from 5-51 ppm with an average 18 ppm, in monzogranites their content was in the range of 11 to 47 ppm with an average value of 27 ppm where it ranges from 14 to 83 ppm with an average 46 ppm in alkali feldspar granite. The enhanced uranium content in altered zones was attributed to disseminated and fracture filling uranophane, autonite, in addition to other U and Th bearing minerals (such as columbite, zircon, monazite, xenotime and fluorite). Gamma-radiation dose rate and annual effective dose equivalents in mSv/y, Radium equivalent activity, external (H e x) and internal hazard index (H i n) and gamma activity index (Iγ) for all investigated samples were calculated to assess the potential radiation hazard for people living in dwellings made of the studied granites. Alkali feldspar granite activities would suggest that caution must be taken when using granites as building materials because they have radioactivity above the proposed acceptable level.

  4. Influence of low dose {gamma} radiation on the dormancy, growth and physiological activity of seed potato (solanum tuberosum L.)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. S.; Lee, Y. K.; Lee, H. Y.; Baek, M. H.; Yoo, Z. C. [KAERI, Taejon (Korea, Republic of)

    2002-05-01

    To observe the stimulating effect of low dose {gamma} radiation on the dormancy breaking and growth of potato with different storage duration and conditions, potato were irradiated with the dose of 1 {approx} 16 Gy. Though varied with storage duration and conditions, sprouting rate of potato stored at 5 .deg. C in the dark was promoted at the 8 and 16 Gy irradiation group compared to 20 .deg. C in the light. The field growth of potato stored at 5 .deg. C in the dark was highly increased at the 2, 4, 8 Gy irradiation group. The CAT activity of potato was increased by about 20% at 1,8 and 16 Gy irradiation group. POD activity was also increased by 7 {approx} 16% at 1, 8 and 16 Gy irradiation group compared to the control. Fv/Fm was not changed by the low dose {gamma} radiation. However, the effective quantum yield of PSII was slightly increased by about 12% at 1 and 16 Gy irradiation group. Seedling irradiated with low dose {gamma} radiation showed the lower excitation pressure on PSII (1- {sub q}P), while NPQ was greatly increased by 45% at 4 Gy irradiation group. These results clearly showed the positive effect of low dose {gamma} radiation on the seedling growth of potato via increasing photoprotective capacities of photosynthetic apparatus.

  5. Effects of low dose gamma-ray radiation on the seed germination and physiological activity of vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. S.; Baek, M. H.; Lee, Y. G. [KAERI, Taejon (Korea, Republic of); Jung, K. H. [Kyunghee Univ., Yongin (Korea, Republic of)

    2000-10-01

    To determine the effect of low dose gamma-ray radiation on the germination rate and physiology of germinative seeds of Chinese cabbage(Brassica campestris L. cv. Hanyoreum) and radish(Raphanus sativus L. cv. Chungsukoungzoung). The germination rate of irradiation group was higher than that of the control. Especially it was highest at the early stage of induction. The germination rate of Chinese cabbage increased at 4 Gy-, 10 Gy- and 50 Gy irradiation group and that of radish increased at 2 Gy-, 6 Gy- and 10 Gy irradiation group. The seedling height of Chinese cabbage and radish increased positively in low dose irradiation group. The seedling height of Chinese cabbage was noticeably higher at 4 Gy and 10 Gy irradiation group and that of radish at 6 Gy irradiation group. The protein contents of seeds irradiated with low dose gamma-ray radiation was increased compared to that of the control especially at the early stage of induction. The enzyme activity of seeds irradiated with low dose of gamma-ray radiation was increased at 4 Gy and 10 Gy irradiation group. These results suggest that the germination and physiological activity of old seeds could be stimulated promisingly by the low dose gamma-ray radiation.

  6. Detection unit for measuring dose rate and/or dose of gamma radiation

    International Nuclear Information System (INIS)

    Viererbl, L.

    1987-01-01

    A detection unit is designed consisting of a scintillation detector of the NaI(Tl) type on which there is a correction filter. The filter is an aluminium case in which are placed alternately side by side lead and iron absorption layers. The sensitivity of the detector with this filter is constant for gamma energy within the range 50 to 1300 keV. (M.D.). 2 figs

  7. Simulation studies to determine the gamma radiation dose due to natural radioactivity in construction materials in dwellings

    International Nuclear Information System (INIS)

    Shetty, P.G.; Chougaonkar, M.P.; Mayya, Y.S.; Puranik, V.D.

    2008-01-01

    Gamma radiation dose is imparted to the living due to the natural radionuclides present in the environmental materials, including the building materials used for construction of dwellings. The radionuclides responsible for natural radiation dose are the primordial radionuclides of 232 Th, 238 U series and the 40 K. These nuclides together with their daughters give rise to external gamma ray dose as well as the inhalation doses arising from the short-lived radon/thoron gases and their progenies that are exhaled from the walls of the construction materials. The radioactivity inside a room and the radiation dose caused by it mainly depends on the concentration of the above mentioned radionuclides in the building materials and type/properties like thickness, density etc. of the material used for construction. A computational model for a standard house (without windows and door) has been designed using Monte Carlo N-particle code (MCNP). The code works on probability theory. The present paper discusses the individual contribution of doses from 40 K, uranium and thorium series. Further variation in the gamma doses due to different building materials and densities are also discussed. (author)

  8. Gamma radiation in apartments

    International Nuclear Information System (INIS)

    Grindborg, J.-E.

    1983-05-01

    This investigation forms the basis for the description of methods for the detection of gamma radiation. The aim is to control that the dose limit will not exceed 50 μR/h in a room where people reside. The distribution of dose rates in different rooms has been calculated and the results have been compared with experimental data. Various instruments have been calibrated and their specifications are discussed. (G.B.)

  9. Mechanism of action for anti-radiation vaccine in reducing the biological impact of high-dose gamma irradiation

    Science.gov (United States)

    Maliev, Vladislav; Popov, Dmitri; Jones, Jeffrey A.; Casey, Rachael C.

    Ionizing radiation is a major health risk of long-term space travel, the biological consequences of which include genetic and oxidative damage. In this study, we propose an original mechanism by which high doses of ionizing radiation induce acute toxicity. We identified biological components that appear in the lymphatic vessels shortly after high-dose gamma irradiation. These radiation-induced toxins, which we have named specific radiation determinants (SRD), were generated in the irradiated tissues and then circulated throughout the body via the lymph circulation and bloodstream. Depending on the type of SRD elicited, different syndromes of acute radiation sickness (ARS) were expressed. The SRDs were developed into a vaccine used to confer active immunity against acute radiation toxicity in immunologically naïve animals. Animals that were pretreated with SRDs exhibited resistance to lethal doses of gamma radiation, as measured by increased survival times and survival rates. In comparison, untreated animals that were exposed to similar large doses of gamma radiation developed acute radiation sickness and died within days. This phenomenon was observed in a number of mammalian species. Initial analysis of the biochemical characteristics indicated that the SRDs were large molecular weight (200-250 kDa) molecules that were comprised of a mixture of protein, lipid, carbohydrate, and mineral. Further analysis is required to further identify the SRD molecules and the biological mechanism by which they mediate the toxicity associated with acute radiation sickness. By doing so, we may develop an effective specific immunoprophylaxis as a countermeasure against the acute effects of ionizing radiation.

  10. Effects of gamma radiation in a wide range of doses on the morphological characteristics of Lemna minor L

    International Nuclear Information System (INIS)

    Rasskazova, M.M.; Berestina, A.V.

    2011-01-01

    The effects of gamma radiation on the morphological parameters of Lemna minor L. were studied. As the sensitive parameters were invited to use chlorosis and necrosis. Significant differences between samples begin to show after 14 days of observation. The presence of effect, irrespective of the dose in the range 0,1-30 Gy, shows the efficiency of a sufficiently small dose (0,1 Gy) was revealed.

  11. Activation of the JET vacuum vessel: a comparison of calculated with measured gamma-radiation fluxes and dose rates

    International Nuclear Information System (INIS)

    Jarvis, O.N.; Sadler, G.; Avery, A.; Verschuur, K.A.

    1988-01-01

    The gamma-radiation dose-rates inside the JET vacuum vessel due to induced radioactivity were measured at intervals throughout the 1986 period of operation, and the decay gamma energy spectrum was measured during the subsequent lengthy shutdown. The dose-rates were found to be in good agreement with values calculated using the neutron yield records compiled from the time-resolved neutron yield monitor responses for individual discharges. This result provides strong support for the reliability of the neutron yield monitor calibration. (author)

  12. Immediate Dose Assessment for Radiation Accident in Laboratory Containing Gamma Source and/or Neutron Source

    International Nuclear Information System (INIS)

    Ahmed, E.M.

    2012-01-01

    One of the most important safety requirements for any place containing radiation sources is an accurate and fast way to assess the dose rate in both normal and accidental case. In normal case, the source is completely protected inside its surrounded shields in case of non use. In some cases this source may stuck outside its shield. In this case the walls of the place act as a shield. Many studies were carried for obtaining the most appropriate materials that may be used as shielding depending on their efficiency and also their cost. As concrete- with different densities- is the most available constructive material, this study presented a theoretical model using MCNP-4B code, based on Monte Carlo method to estimate the dose rate distribution in a laboratory with concrete walls in case of source stuck accident. The study dealt with Cs-137 as gamma source and Am-Be-241 as neutron source. Two different densities of concrete and also different thicknesses of walls were studied. The used model was verified by comparing the results with a practical study concerning with the effect of adding carbon powder to the concrete. The results showed good agreement

  13. Evaluation of the radiation doses to uranium mine employees exposed to external gamma radiation

    International Nuclear Information System (INIS)

    Young, J.G.; Wilson, O.J.

    1983-02-01

    Factors to convert a personal monitor badge reading to an effective dose equivalent are given for several exposure geometries encountered in uranium mines. Factors are also given that relate a free air absorbed dose measurement to an effective dose equivalent. In addition, factors are reported which can be used to estimate the dose equivalent to the testes, ovaries and active bone marrow

  14. Mechanism of Action for Anti-radiation Vaccine in Reducing the Biological Impact of High-dose Gamma Irradiation

    Science.gov (United States)

    Maliev, Vladislav; Popov, Dmitri; Jones, Jeffrey A.; Casey, Rachael C.

    2007-01-01

    Ionizing radiation is a major health risk of long-term space travel, the biological consequences of which include genetic and oxidative damage. In this study, we propose an original mechanism by which high doses of ionizing radiation induce acute toxicity. We identified biological components that appear in the lymphatic vessels shortly after gamma irradiation. These radiation-induced toxins, which we have named specific radiation determinants (SRD), were generated in the irradiated tissues and then collected and circulated throughout the body via the lymph circulation and bloodstream. Depending on the type of SRD elicited, different syndromes of acute radiation sickness (ARS) were expressed. The SRDs were developed into a vaccine used to confer active immunity against acute radiation toxicity in immunologically naive animals. Animals that were pretreated with SRDs exhibited resistance to lethal doses of gamma radiation, as measured by increased survival times and survival rates. In comparison, untreated animals that were exposed to similar large doses of gamma radiation developed acute radiation sickness and died within days. This phenomenon was observed in a number of mammalian species. Initial analysis of the biochemical characteristics indicated that the SRDs were large molecular weight (200-250 kDa) molecules that were comprised of a mixture of protein, lipid, carbohydrate, and mineral. Further analysis is required to further identify the SRD molecules and the biological mechanism by which the mediate the toxicity associated with acute radiation sickness. By doing so, we may develop an effective specific immunoprophylaxis as a countermeasure against the acute effects of ionizing radiation.

  15. Survey of the gamma dose rate and locations with extremely abnormal radiation

    International Nuclear Information System (INIS)

    Sansoni, B.; Matthes, W.

    1985-01-01

    The goals pursued by the investigation on hand were: (a) to get a survey of natural radioactivity in the Fichtelgebirge; (b) to find and describe locally restricted areas of high natural radioactivity (abnormal radiation, hot spots); this will be a starting point (c) for the assessment of possible increased radiation exposure and of the state of health of a restricted number of persons. Furthermore, there are also (d) underground data for the eventual stipulation of maximum permissible values for natural radioactivity. (e) The situation in the Fichtelgebirge shall be compared with that of the monazite sand-stone areas in India. The highest gamma dose rates measured in locally restricted areas were: (1) granite road pavement: 24 μR/h; (2) granite quarries (35 μR/h); (3) caves below granite rock (40 to 70 μR/h); (4) slag brick pavement on market place and main street of Marktredwitz (53.4 μR/h) (part of which removed already); (5) uranium abnormalities on a farmer's field (80-100 μR/h) (0.6 m below the surface: 1.500 μR/h); this may be considered a uranium deposit with a content in uranium of up to 0.3%; (6) over 100 μR/h in front of an uranium ore mine in the uranium prospection drift (rest of the drift in the granite no more than 29.3+-3.3 μR/h). The resulting maximum conceivable radiation exposure is assessed. The question whether there is a necessity for setting tolerance limit values for natural radioactivity is raised again; the magnitude in comparison with limit values for artificial radioactivity in radioactive controlled areas is pointed out. (orig./HP) [de

  16. Combined effects of gamma radiation doses and sodium nitrite content on the lipid oxidation and color of mortadella.

    Science.gov (United States)

    Dutra, Monalisa Pereira; Cardoso, Giselle Pereira; Fontes, Paulo Rogério; Silva, Douglas Roberto Guimarães; Pereira, Marcio Tadeu; Ramos, Alcinéia de Lemos Souza; Ramos, Eduardo Mendes

    2017-12-15

    The effects of different doses of gamma radiation (0-20kGy) on the color and lipid oxidation of mortadella prepared with increasing nitrite levels (0-300ppm) were evaluated using a central composite rotatable design. Higher radiation doses increased the redox potential, promoted the lipid oxidation and elevating the hue color of the mortadellas. Nevertheless, higher addition of sodium nitrite elevated the residual nitrite content, reduced the lipid oxidation and promoted the increase of redness and the reduce of hue color of the mortadellas, regardless of the radiation dose applied. Nitrite addition had a greater effect than irradiation on the quality parameters evaluated, and even at low levels (∼75ppm), its use decreased the deleterious effects of irradiation at doses as high as 20kGy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Histochemical changes of capillaries in rat brain cortex after irradiation with supralethal doses of gamma radiation

    International Nuclear Information System (INIS)

    Kamarad, V.; Dosoudilova, M.

    1987-01-01

    Changes were studied in the activities of alkaline phosphatase, ATP-splitting enzyme, thiaminepyrophosphatase, acetylcholinesterase, and of butyrylcholinesterase in the capillary sheet of the rat brain cortex of the laterobasal section of a parietal lobe following irradiation with 150 and 300 Gy. The animals were exposed to local irradiation of the head with gamma radiation using 60 Co at a dose rate of 6.9 Gy per min. The material was removed at the intervals of 30 and 60 mins after irradiation. All the studied enzymes, except the ATP-splitting enzyme, showed identical reaction to irradiation. At both intervals, the reaction after irradiation with 300 Gy was lower when compared to that after irradiation with 150 Gy. 30 mins after irradiation with 150 Gy an increased enzyme activity was shown followed by a marked decrease in the activity 60 mins after irradiation, compared with findings obtained from control animals. No similar time dependence was observed after irradiation with 300 Gy. The ATP-splitting enzyme showed a significant decrease in the activity 30 mins after irradiation with 150 Gy. On the other hand, 60 mins after irradiation with 150 Gy and at both time intervals after irradiation with 300 Gy, the activity was higher than that in control animals. (author). 6 figs., 14 refs

  18. Terrestrial gamma radiation dose study to determine the baseline for environmental radiological health practices in Melaka state, Malaysia

    International Nuclear Information System (INIS)

    Ramli, Ahmad Termizi; Sahrone, Sallehudin; Wagiran, Husin

    2005-01-01

    Environmental terrestrial gamma radiation dose rates were measured throughout Melaka, Malaysia, over a period of two years, with the objective of establishing baseline data on the background radiation level. Results obtained are shown in tabular, graphic and cartographic form. The values of terrestrial gamma radiation dose rate vary significantly over different soil types and for different underlying geological characteristics present in the study area. The values ranged from 54 ± 5 to 378 ± 38 nGy h -1 . The highest terrestrial gamma dose rates were measured over soil types of granitic origin and in areas with underlying geological characteristics of an acid intrusive (undifferentiated) type. An isodose map of terrestrial gamma dose rate in Melaka was drawn by using the GIS application 'Arc View'. This was based on data collected using a NaI(Tl) scintillation detector survey meter. The measurements were taken at 542 locations. Three small 'hot spots' were found where the dose rates were more than 350 nGy h -1 . The mean dose rates in the main population areas in the mukims (parishes) of Bukit Katil, Sungai Udang, Batu Berendam, Bukit Baru and Bandar Melaka were 154 ± 15, 161 ± 16, 160 ± 16, 175 ± 18 and 176 ± 18 nGy h -1 , respectively. The population-weighted mean dose rate throughout Melaka state is 172 ± 17 nGy h -1 . This is lower than the geographical mean dose rate of 183 ± 54 nGy h -1 . The lower value arises from the fact that most of the population lives in the central area of the state where the lithology is dominated by sedimentary rocks consisting of shale, mudstone, phyllite, slate, hornfels, sandstone and schist of Devonian origin which have lower associated dose rates. The mean annual effective dose to the population from outdoor terrestrial gamma radiation was estimated to be 0.21 mSv. This value is higher than the world average of 0.07 mSv

  19. Aspartame tablets-gamma dose response and usability for routine radiation processing dosimetry using spectrophotometry

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, S.H. [Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)]. E-mail: shs_barc@yahoo.com; Mukherjee, T. [Radiation Safety Systems Division, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

    2007-02-15

    Aspartame tablets were studied for gamma dose response, using spectrophotometric read-out method. The optimum concentration for ferrous ions was 2x10{sup -4}moldm{sup -3} and xylenol orange with 2.5x10{sup -1}moldm{sup -3} of sulphuric acid for the optimum acidity in FX solution. Wavelength of maximum absorbance is 548nm. Post-irradiation stability is appreciable i.e. for not less than one month. Dose response is non-linear with third order polynomial fit, in the dose range of 1000-10000Gy. This system of aspartame was further used for carrying out relative percentage dose profile measurement in Gamma Cell-220. Results obtained were inter-compared with that of a glutamine dosimeter, which showed that maximum difference between the values of aspartame and glutamine systems is within +/-10%.

  20. Aspartame tablets-gamma dose response and usability for routine radiation processing dosimetry using spectrophotometry

    International Nuclear Information System (INIS)

    Shinde, S.H.; Mukherjee, T.

    2007-01-01

    Aspartame tablets were studied for gamma dose response, using spectrophotometric read-out method. The optimum concentration for ferrous ions was 2x10 -4 moldm -3 and xylenol orange with 2.5x10 -1 moldm -3 of sulphuric acid for the optimum acidity in FX solution. Wavelength of maximum absorbance is 548nm. Post-irradiation stability is appreciable i.e. for not less than one month. Dose response is non-linear with third order polynomial fit, in the dose range of 1000-10000Gy. This system of aspartame was further used for carrying out relative percentage dose profile measurement in Gamma Cell-220. Results obtained were inter-compared with that of a glutamine dosimeter, which showed that maximum difference between the values of aspartame and glutamine systems is within +/-10%

  1. Dosimetric and Clinical Analysis of Spatial Distribution of the Radiation Dose in Gamma Knife Radiosurgery for Vestibular Schwannoma

    International Nuclear Information System (INIS)

    Massager, Nicolas; Lonneville, Sarah; Delbrouck, Carine; Benmebarek, Nadir; Desmedt, Françoise; Devriendt, Daniel

    2011-01-01

    Objectives: We investigated variations in the distribution of radiation dose inside (dose inhomogeneity) and outside (dose falloff) the target volume during Gamma Knife (GK) irradiation of vestibular schwannoma (VS). We analyzed the relationship between some parameters of dose distribution and the clinical and radiological outcome of patients. Methods and Materials: Data from dose plans of 203 patients treated for a vestibular schwannoma by GK C using same prescription dose (12 Gy at the 50% isodose) were collected. Four different dosimetric indexes were defined and calculated retrospectively in all plannings on the basis of dose–volume histograms: Paddick conformity index (PI), gradient index (GI), homogeneity index (HI), and unit isocenter (UI). The different measures related to distribution of the radiation dose were compared with hearing and tumor outcome of 203 patients with clinical and radiological follow-up of minimum 2 years. Results: Mean, median, SD, and ranges of the four indexes of dose distribution analyzed were calculated; large variations were found between dose plans. We found a high correlation between the target volume and PI, GI, and UI. No significant association was found between the indexes of dose distribution calculated in this study and tumor control, tumor volume shrinkage, hearing worsening, loss of functional hearing, or complete hearing loss at last follow-up. Conclusions: Parameters of distribution of the radiation dose during GK radiosurgery for VS can be highly variable between dose plans. The tumor and hearing outcome of patients treated is not significantly related to these global indexes of dose distribution inside and around target volume. In GK radiosurgery for VS, the outcome seems more to be influenced by local radiation dose delivered to specific structures or volumes than by global dose gradients.

  2. Effects of sublethal doses of gamma radiation on the developing rat brain

    International Nuclear Information System (INIS)

    Cerda, H.; Carlsson, J.; Larsson, B.; Saefwenberg, J.O.

    1975-01-01

    Newborn rats were irradiated with 60 Co gamma rays. Doses of 0, 80 or 160 rads were given to the whole body. The whole body and brain weights, DNA and RNA contents of the brain and 3 H-thymidine or 3 H-uridine incorporated by the brain were measured at 5, 10 or 15 days after birth. A dose of 160 rads produced clear alterations in the brain but no clear effects could be detected when 80 rads were given. (author)

  3. Influence of Exposure to Fractionated Dose of Gamma Radiation and Antioxidants Supplementation to Mice on program cell death induction

    International Nuclear Information System (INIS)

    Hanafi, A.

    2010-01-01

    The previous studies reported that the tumor suppressor protein (P53) is not functioning correctly in most human cancers, and that it plays a crucial role in the prevention of tumor development. This study was designed to evaluate if exposure to fractionated dose of gamma radiation impair function of P53 by the administration of antioxidants. Group of control mice was used. Another groups treated with 3 mg/mouse/day of Antox drug which contains the three main antioxidant vitamins (A, C, and E) together with trace element selenium for 15 days. Another group subjected to 1 Gy of gamma radiation 5 times every other day either alone or combined with the Antox drug supplementation. Hepatic and renal functions were evaluated. Antioxidant markers (MDA and GSH) levels, histopathological changes and P53 expression were recorded in liver and kidney tissues. Animals treated with Antox showed some increase in liver transaminases, non significant changes in total protein and albumin levels, a non significant change in kidney function profiles, a non significant increase in MDA and a significant increase in GSH levels in liver and kidney tissues. However, the exposure of mice to fractionated dose of gamma radiation led to a significant increase in kidney function profiles, AST and ALT activity, a significant decrease in total protein and albumin level, a significant increase in MDA levels and a significant decrease in GSH levels in liver and kidney were observed. Exposure of experimental animals post treatment with Antox drug to fractionated dose of gamma radiation revealed a significant amelioration in liver and kidney function profiles, a highly significant decrease in MDA levels and a significant increase in GSH level in comparison with irradiated group. Histopathological changes in liver and kidney recorded the same alterations observed with the biochemical parameters. P53 expression negatively expressed in normal liver and kidney tissues. However, the exposure of mice to

  4. Chronic action of gamma-radiation on growing cell population of the yeast Saccharomyces cerevisiae at various dose rates

    International Nuclear Information System (INIS)

    Zyuzikov, N.A.; Petin, V.G.

    1996-01-01

    Experimental data on the processes of division and death of haploid and diploid yeast Saccharomyces cerevisiae of wild type and of their radiosensitive mutants exposed under optimal for reproduction conditions to chronic gamma-radiation at various dose rates are presented. It is shown that the dependence of the integral division/death process in time was exponential for all the studied strains. With dose rate increasing, the duration of the lag period and the probability of cell inactivation increased, while the multiplication rate decreased. These processes, for equal dose rates, were more expressed for the radiosensitive mutants

  5. Influence of high-dose gamma radiation and particle size on antioxidant properties of Maize ( Zea mays L.) flour

    International Nuclear Information System (INIS)

    Nawaz, Haq; Shad, Muhammad Aslam; Rehman, Tanzila; Ramzan, Ayesha

    2016-01-01

    Influence of high-dose gamma radiation and particle size on antioxidant properties of maize (Zea mays L.) flour was studied using response surface methodology. A central composite design based on three levels of each of particle size, in terms of mesh number (40, 60 and 80 meshes), and gamma radiation dose (25, 50 and 75 kGy) was constructed. A statistically significant dose-dependent decrease (p<0.05) in antioxidant properties of gamma irradiated flour was observed. However, an increase in the mesh number (decrease in particle size of flour) resulted in an increase in antioxidant properties. The optimum level of radiation dose to achieve maximum value of responses was found to be 50 kGy for Trolox equivalent total antioxidant activity (TETAOA), 25 kGy for iron chelating ability (ICA), 25 kGy for reducing power (RP) and 75 kGy for linoleic acid reduction capacity (LARC). However, the optimum level of mesh number to achieve desired levels of TETAOA, ICA, RP and LARC was found to be 80 meshes. (author)

  6. Influence of high-dose gamma radiation and particle size on antioxidant properties of Maize ( Zea mays L.) flour

    Energy Technology Data Exchange (ETDEWEB)

    Nawaz, Haq; Shad, Muhammad Aslam; Rehman, Tanzila; Ramzan, Ayesha, E-mail: haqnawaz@bzu.edu.pk [Bahauddin Zakariya University, Multan (Pakistan)

    2016-10-15

    Influence of high-dose gamma radiation and particle size on antioxidant properties of maize (Zea mays L.) flour was studied using response surface methodology. A central composite design based on three levels of each of particle size, in terms of mesh number (40, 60 and 80 meshes), and gamma radiation dose (25, 50 and 75 kGy) was constructed. A statistically significant dose-dependent decrease (p<0.05) in antioxidant properties of gamma irradiated flour was observed. However, an increase in the mesh number (decrease in particle size of flour) resulted in an increase in antioxidant properties. The optimum level of radiation dose to achieve maximum value of responses was found to be 50 kGy for Trolox equivalent total antioxidant activity (TETAOA), 25 kGy for iron chelating ability (ICA), 25 kGy for reducing power (RP) and 75 kGy for linoleic acid reduction capacity (LARC). However, the optimum level of mesh number to achieve desired levels of TETAOA, ICA, RP and LARC was found to be 80 meshes. (author)

  7. Adaptive response to ionizing radiation induced by low doses of gamma rays in human cell lines

    International Nuclear Information System (INIS)

    Seong, Jinsil; Chang, Ok Suh; Gwi, Eon Kim

    1995-01-01

    Purpose: The aim of this study was to investigate whether the adaptive response could be induced in human lymphoblastoid cell lines and human tumor cell lines. The time necessary for the expression of the adaptive response was also investigated. Materials and Methods: Three lymphoblastoid cell lines from ataxia telangiectasia (AT) homozygote (GM 1526), AT heterozygote (GM 3382), and normal individual (3402p) and two hepatoma cell lines, Hep G2 and Hep 3B, were used in this study. Experiments were carried out by delivering 0.01 Gy followed by 0.5 Gy of gamma radiation to the exponentially growing cells. The time necessary for the expression of the adaptive response was determined by varying the time interval between the two doses from 1 to 72 h. In some experiments, 3-aminobenzamide, a potent inhibitor of poly (ADP-ribose) polymerase, was added immediately after the 0.5 Gy exposure. The cultures were fixed 30 min (for the G 2 chromatid) and 6 h (for the S chromatid) after the 0.5 Gy exposure. Metaphase chromosome assay was carried out to score chromatid breaks as an end point. Results: A prior exposure to 0.01 Gy of gamma rays significantly reduced the number of chromatid breaks induced by subsequent higher doses (0.5 Gy) in all the tested cell lines. The magnitude of the adaptive response was similar among the cell lines despite their different radiosensitivities. In the G 2 chromatids, the adaptive response was observed both at short-time intervals, as early as 1 h, and at long-time intervals. In the S chromatids, however, the adaptive response was shown only at long-time intervals. When 3-aminobenzamide was added after the 0.5 Gy, the adaptive responses were abolished in all the experimental groups. Conclusion: The adaptive response was observed in human lymphoblastoid cell lines and hepatoma cell lines. The magnitude of the adaptive response did not seem to be related to the radiosensitivity of the cells. The elimination of the adaptive response with 3

  8. Effects of low dose gamma- and UV-radiation on sea urchin eggs and spermatozoa

    International Nuclear Information System (INIS)

    Czihak, G.K.

    1991-01-01

    The paper outlines the results of a study of the effects of low dose gamma-and UV-irradiation on sea urchin eggs and spermatozoa with particular reference to the effects on the stages of the mitotic cycle and individual susceptibility. (UK)

  9. Gamma dosimetry of high doses

    International Nuclear Information System (INIS)

    Martinez C, T.; Galvan G, A.; Canizal, G.

    1991-01-01

    The gamma dosimetry of high doses is problematic in almost all the classic dosemeters either based on the thermoluminescence, electric, chemical properties, etc., because they are saturated to very high dose and they are no longer useful. This work carries out an investigation in the interval of high doses. The solid system of heptahydrate ferrous sulfate, can be used as solid dosemeter of routine for high doses of radiation. The proposed method is simple, cheap and it doesn't require sophisticated spectrophotometers or spectrometers but expensive and not common in some laboratories

  10. Effect of low doses of gamma radiation on barley tolerance grown under saline conditions

    International Nuclear Information System (INIS)

    Charbaji, T.; Khalifa, Kh; Al-Ain, F.

    2003-01-01

    A field experiment was conducted at Al-Hijanah, an area located at about 35 km south east of Damascus. Seeds of two barley varieties [White Arabi (WA) and Pakistani 30163 (PK) were irradiated with 2 doses 0 and 15 Gy of gamma irradiation. Then, they were shown on salty soil (17.6-18,9 m mos/cm) and irrigated with salty water (5.12-5.75 m mos/cm). A dose of 15 Gy of gamma irradiation was shown to positively affect the percent germination of PK but had no similar effect on WA. The results were obtained at 3 different growth stages: first, the heading stage, 15 Gy dose increased shoots dry weight, Mg ++ , P content and percent of WA, whereas N percent of PK was decreased. When the seeds were irradiated by the same dose. K + content in WA was significantly higher than that in PK. Second, physiological maturity stage, the same dose (15 Gy) increased shoot dry, but affected negatively K + and Na + contents in PK variety. As for WA variety, Mg ++ and P contents were increased, whereas Na + and Cl - were slightly decreased. Third, harvest stage, gamma irradiation had a positive effect on total yield, grain yield, nitrogen yield and harvest index of PK variety. A positive effect was produced on straw yield, 1000-grain weight, and nitrogen yield of WA variety. (author)

  11. Effect of low dose {gamma} radiation on the dormancy breaking and physiological activity of 'Dejima' seed potato

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. S.; Kim, D. H.; Baek, M. H.; Lee, Y. K. [KAERI, Taejon (Korea, Republic of); Lee, Y. B. [Chungnam National Univ., Taejon (Korea, Republic of)

    2001-05-01

    To observe the stimulating effects of low dose {gamma}-radiation on the dormancy breaking and physiological activity, potato (Solanum tuberosum L. cv. Dejima) were irradiated at the dose of 0.5 {approx} 30 Gy. Low dose {gamma}-radiation had promoting effects on the srouting rate the optimum dose of 1 Gy and 2 Gy and on the sprout length at the optimum dose of 2 Gy and 4 Gy. In case of number of sprouts, there were increased in all of the low dose irradiation groups and period storages, which showed very significant promoting effects at 4,8,16 Gy of 15 DAP. The field growth of 45 DAP were increased at all of the low dose irradiation group, which particularly were very significant promoting effect at 4 Gy irradiation group. Irradiation didn't have significant effects on the antioxidant enzyme activity of potato plantlet, but the peroxidase activity of 45 DAP plantlet increased at 4 Gy irradiation group.

  12. The ferrous ammonium sulfate solid system, as dosemeter for processes at low temperatures and high doses of gamma radiation

    International Nuclear Information System (INIS)

    Juarez C, J.M.; Ramos B, S.; Negron M, A.

    2005-01-01

    This paper presents the results obtained from a study of the radiation induced oxidation of crystalline ferrous ammonium sulfate with gamma rays at 295 K, 263 K and 77 K and dose from 0 to 300 kGy. The radiation induced decomposition of ferrous ammonium sulfate has been studied by the dissolution of the irradiated salt in 0,8 N sulfuric acid. The main product is Fe 3+ and molar concentration of ferric ion was determined spectrophotometrically in the UV region at 304 nm. The optical density values showed a linear dependence with dose, indicating that the data obtained might be used to create a calibrating curve. Color in irradiated salt changes from blue to green, yellow and orange according to the absorbed dose. The accuracy and the reproducibility of the system were tested. In addition, some other characteristics make possible the use of this system as a dosimeter, similar to Fricke chemical dosemeter, at low temperatures and high dose. (Author)

  13. Influence of radiation-dose pattern from inhaled beta--gamma-emitting radionuclides on canine peripheral lymphocytes

    International Nuclear Information System (INIS)

    Jones, R.K.; Boecker, B.B.; Pickrell, J.A.; Hobbs, C.H.; McClellan, R.O.

    1976-01-01

    As part of studies assess the biological hazards associated with inhaled radionuclides, periodic hematologic evaluations were performed on beagle dogs given a single nose-only exposure to aerosols of beta--gamma-emitting isotopes. The physical form and specific radionuclides selected produced radiation-dose patterns representative of those which might be encountered in the event of human accidental exposures. Dogs received graded lung burdens of either 90 Y, 91 Y, 144 Ce, or 90 Sr, each in fused clay. Differences in the effective half-lives of these radionuclides resulted in a spectrum of cumulative radiation doses to lung delivered at a variety of dose rates. Since the form in which the radionuclides were inhaled was relatively insoluble, the lung and intrathoracic tissues represented the primary recipient of the dose. Regardless of the effective half-life of radionuclide retention, a dose-related depression of peripheral lymphocytes was observed at various times after inhalation exposure. The time at which maximum depression and subsequent recovery occurred, however, was most directly related to the effective half-life of the radionuclide. Of special interest was the persistence of lymphopenia through 2 1 / 2 years after exposure to 144 Ce and 90 Sr in fused clay where, other than tracheobronchial lymph nodes, the lymphoid tissue received very little radiation dose. The possible mechanisms responsible for lymphocyte depression from these various radiation-dose patterns are discussed

  14. New model for assessing dose and dose rate sensitivity of Gamma ray radiation loss in polarization maintaining optical fibers

    International Nuclear Information System (INIS)

    Zhang Hongchen; Liu Hai; Qiao Wenqiang; Xue Huijie; He Shiyu

    2012-01-01

    Highlights: ► Building a new phenomenological theory model to investigate the relation about the irradiation induced loss with irradiation dose and dose rate. ► The Gamma ray irradiation induced loss of the “Capsule” type and “Panda” type polarization maintaining optical fibers at 1310 nm wavelength are investigated. ► The anti irradiation performance of the “Panda” type polarization maintaining optical fiber is better than that of the “Capsule” type polarization maintaining optical fiber, the reason is that the stress region doped by GeO 2 . - Abstract: The Gamma ray irradiation induced loss of the “Capsule” type and “Panda” type polarization maintaining optical fibers at 1310 nm wavelength are investigated. A phenomenological theory model is introduced and the influence of irradiation dose and dose rate on the irradiation induced loss is discussed. The phenomenological theoretical results are consistent with the experimental results of the irradiation induced loss for the two types of polarization maintaining optical fibers. The anti irradiation performance of the “Panda” type polarization maintaining optical fiber is better than that of the “Capsule” type polarization maintaining optical fiber, the reason is that the stress region dope with GeO 2 . Meanwhile, both of the polarization maintaining optical fiber irradiation induced loss increase with increasing the irradiation dose. In the case of same dose, the high dose rate Gamma ray irradiation induced optical fiber losses are higher than that of the low dose rate.

  15. Role of Immunomodulators in Tumor Regression in Mice Exposed to Fractionated Low Dose of Gamma Radiation

    International Nuclear Information System (INIS)

    Rokaya Elsayed Maaroaf Elsayed

    2015-01-01

    Immunotherapy is one of the most promising approaches of cancer treatment. The present study was designed to examine the role of irradiated tumor cell lysate vaccine, IFNα-2b and low dose of gamma irradiation as immunomodulators either alone or combined in tumor regression. Ehrlich ascite carcinoma (EAC) cells and 9 groups of female mice were used. Mice were immunized intramuscularly by tumor cell lysate vaccine one time/week for 3 weeks in the right thigh of mice. After two weeks from last immunization, all mice were challenged with normal viable EAC cells at count of 2.5 ×10 6 /mouse in the opposite left thigh for Ehrlich carcinoma (EC) production. Mice were subcutaneously injected with 10.000 units of IFNα-2b 3 times/week for 4 weeks and others were exposed to fractionated dose of γ- radiation (0.5 Gy/day x 4, day after day). Tumor size, serum tumor markers (TNF-α and CEA), tumor DNA fragmentation and Caspase-3 were evaluated. Oxidative stress (MDA and NO) markers and antioxidants (GSH, GPX and SOD) were determined in spleen and tumor tissues. Histopathological examinations, apoptosis and necrosis in spleen and tumor tissues were also examined. The results revealed significant inhibition in tumor size throughout the observation period either for treatments with vaccine or IFNα-2b either alone or combined with γ-irradiation. DNA fragmentation and Caspase-3 enzyme activities were significantly elevated in immunized mice as compared with EC group along with diminished tumor size while, tumor markers were significantly decreased. MDA and NO were significantly increased in tumor tissue.while, tumor GSH content, GPX and SOD activities were significantly decreased. Combined treatments of female mice bearing EC with IFN-α-2b, tumor cell lysate vaccine and low dose of γ-radiation cause a highly significant decrease in serum TNF-α and CEA levels, increase in Cas-3 activity, no DNA fragmentation, significant increase in MDA, decrease in SOD activity and decreased

  16. Interaction of gamma radiation and temperature on the determination of the sterilizing dose of some stored products pests

    International Nuclear Information System (INIS)

    Barbosa, A.P.

    1976-08-01

    The influence of temperature on sterilizing dosages of gamma radiation was studied for Sitophilus zeamais Mots. in corn, Sitophilus oryzae (L.) in rice, Araecerus fasciculatus (DeGeer) in coffee, and Zabrotes subfasciatus (Boh.) in beans. It was found that temperature has a significant influence on the amount of radiation required to sterilize these species. The highest radiation dosages were required at those temperature most nearly optimum for insect development. The minimum radiation doses required for complete sterility of each species at the indicated temperatures were as follows: Sitophilus zeamais Mots. in corn, 8 krad at 24 0 C; Sitophilus oryzae (L.) in rice, 9 krad at 24 0 C; Araecerus fasciculatus (DeGeer) in coffee, 6 krad at 30 0 C; Zabrotes subfasciatus (Boh.) in beans, 9 krad at 24 - 27 0 C. At either higher or lower temperature smaller radiation dosages were required. (author) [pt

  17. Sensory evaluation of Regina freestone peaches treated with low doses of gamma radiation

    International Nuclear Information System (INIS)

    O'Mahony, M.; Wong, S.Y.; Odbert, N.

    1985-01-01

    Sensory appraisal of low post-harvest gamma irradiation dosing (65-75 Krad) of a single batch of peaches revealed significant differences in aroma and in taste components not associated with sweetness, but only slight differences in firmness and appearance. A panel of practiced judges evaluated irradiated and non-irradiated peaches using a technique of minimal cross-sensory inference. The significant differences in aroma and taste also were detected by untrained judges

  18. Simultaneos determination of absorbed doses due to beta and gamma radiations with CaSO4: Dy produced at Ipen

    International Nuclear Information System (INIS)

    Campos, L.L.; Rosa, L.A.R. da.

    1988-07-01

    Due to the Goiania radiological accident, it was necessary to develop urgently a dosimeter in order to evaluate, simultaneously, beta and gamma absorbed doses, due to 137 Cs radiations. Therefore, the Dosimetric Material Production Laboratory of IPEN developed a simple, practical, light and low cost badge using small thickness (0,20mm) thermoluminescent CaSO 4 : Dy pellets produced by the same laboratory. This pellets are adequate for beta radiation detection. These dosimeters were worn by some IPEN technicians who worked in Goiania city, and were used to evaluate the external and internal contaminations presented by the accident victims interned at the Hospital Naval Marcilio Dias. (author) [pt

  19. Effects of differents gamma radiation doses absorbed for postharvest tomato fruits

    International Nuclear Information System (INIS)

    Silva Abreu, Toneypson da; Jesus, Edgar F.O. de; Soares, Antonio G.

    1997-01-01

    Postharvest tomato fuits Santa Cruz were submitted to prestorage gamma irradiation treatment with different doses range zero (unirradiated fruits) to 1000 Gy. The aim of this study is to evaluate the postharvest quality parameters: Hunter colour values for light transmittance analysis, pH, total titratable acidity, total soluble solids, maximum firmness and maturity stage. The fruits were stored under (25±1) 0 C with (93±3) relative humidity. The results obtained from the different irradiated treatments showed 600 Gy as the best dose to increase the shelf-life of tomato fruits and to decay its ripening. (author). 5 refs., 12 figs., 1 tab

  20. Effects of varying doses of gamma radiation on locally adapted Tradescantia clone 02 (BNL) (Brookhaven National Laboratory)

    International Nuclear Information System (INIS)

    Dimaano, Maritess M.; Imperial V, Maria Angelica Liza

    1999-03-01

    This study determined the effects of gamma radiation on the meiotic cells of Tradescantia bracteata clone 02 (BNL). The flower buds collected were exposed through dosages ranging from 1 Gy to 5 Gy using gamma cell 220 machine (AECL) in a central axis position (c/a) and grown in Peralta's solution for three days. Out of the twenty buds designated for each dosages, ten buds were treated with 0.05% colchicine solution. The occurrence of micronuclei among the irradiated pollen mother cells suggested a linear relation with the quantity of radiation dose. The occurrence of MN among cells increased linearly from 1 Gy until it reached 3 Gy and 4 Gy. Beyond this maximum dose, cells were less responsive to the dose caused by inhibition of cell division, as demonstrated in the buds exposed to 5 Gy. This result was validated through the kruskal-Wallis test, where the computed h value was 3.44 (critical region of X 2 0 . 05 = 9.49) Experimental results also showed chromosomal breaks, sticky chromosomes, and anaphase bridges in the pollen mother cells of irradiated buds. A significant numbers of cells were also found to have micronuclei, which may vary from 1 to 6 per pollen mother cell, and this showed no relationship with radiation dose. (Author)

  1. Effect of Low Doses of Gamma Radiation and Nitrogen Fertilization on Growth and Yield of Wheat (Triticum aestivum L.)

    International Nuclear Information System (INIS)

    Moussa, H.R.; Khodary, S.E.A.

    2006-01-01

    An experiment was conducted to study the effect of gamma radiation at the rates of 0.0, 5, 10 and 20 Gy on growth characteristics and total yield of wheat fertilized with 40,80 and 100 kg ha of urea as a source of nitrogen. The application of 100 kg N ha -1 produced 8170 kg ha 1 of grain and 10477 kg ha of straw yield. The nitrogen fertilization increased significantly plant height, 1000-grain weight grain and straw yield. Nitrogen at 100 kg ha -1 produced 8170 kg ha -1 of grain and 10477 kg ha -1 of straw yield. Also, the radiation dose (20 Gy) produced 4895 kg ha -1 of grain and 9150 kg ha 1 of straw yield. The interaction of both radiation dose (20 Gy) and nitrogen fertilization (100 kg ha -1 ) increased significantly the spike length, 1000-grain weight and consequently the total grain and straw yield. It can be concluded from the present study that pretreatment of wheat grain by gamma radiation dose (20 Gy) before.planting and using nitrogen fertilization (100 kg ha -1 ) may be considered as promising useful in increasing the efficiency of wheat productivity, which is very important crop in Egypt

  2. Effects of acute sublethal gamma radiation exposure on aggressive behavior in male mice: A dose-response study

    International Nuclear Information System (INIS)

    Maier, D.M.; Landauer, M.R.

    1989-01-01

    The resident-intruder paradigm was used to assess the effects of gamma radiation (0, 3, 5, 7 Gray [Gy] cobalt-60) on aggressive offensive behavior in resident male mice over a 3-month period. The defensive behavior of nonirradiated intruder mice was also monitored. A dose of 3 Gy had no effect on either the residents' offensive behavior or the defensive behavior of the intruders paired with them. Doses of 5 and 7 Gy produced decreases in offensive behavior of irradiated residents during the second week postirradiation. The nonirradiated intruders paired with these animals displayed decreases in defensive behavior during this time period, indicating a sensitivity to changes in the residents' behavior. After the third week postirradiation, offensive and defensive behavior did not differ significantly between irradiated mice and sham-irradiated controls. This study suggests that sublethal doses of radiation can temporarily suppress aggressive behavior but have no apparent permanent effect on that behavior

  3. Tl response of KMgF3 :Lu+PTFE depending on the dose of gamma radiation of 60Co

    International Nuclear Information System (INIS)

    Lopez, A.; Gonzalez, P.R.; Furetta, C.; Azorin, J; Rivera, T.; Sepulveda, F.

    2002-01-01

    Due to the great interest in Tl dosimetry for measuring the levels of radiation doses, as environmental as in the different medical radiation applications in different laboratories of the World it is continued in the searching of new Tl materials with optimum dosimetric characteristics and low cost. In this work the obtained results when irradiating Tl dosemeters of KMgF 3 :Lu + PTFE with gamma radiation of 60 Co are presented. Such results showed that this material presents linearity of response depending on the dose between 0.016 to 100 Gy. Although it is continued with the characterization tests it is able to say that this Tl new material can be used for dosimetric aims. (Author)

  4. Effect of dose fractionation of 60Co gamma radiation on longevity and reproduction of Sitophilus granarius (L., 1785) (Col., Curculionidae) in wheat

    International Nuclear Information System (INIS)

    Arthur, V.; Walder, J.M.M.; Wiendl, F.M.; Domarco, R.E.; Haddad, S.S.

    1987-01-01

    The effects of fractionated doses of gamma radiation in different interval of time on longevity and reproductivity of Sitophilus granarius (L., 1785) are studied. Gamma radiation was provided at dose rate of 1.56 kGy/hour by a Cobalt 60 source (Gammabeam-650). The insects were divided in two sets: one was irradiated at acute doses and the other in fractionated doses, with interval of 48 hours. Both sets received doses of 0,40, 50, 60, 70, 80, 90 and 100Gy. Mortality and and emergency were determined weekly. (M.A.C.) [pt

  5. Fourth IRMF comparison of calibrations of portable gamma-ray dose- rate monitors 2001-2002 Ionising radiation

    CERN Document Server

    Lewis, V E

    2002-01-01

    The Ionising Radiations Metrology Forum (IRMF) organised a fourth comparison of calibrations of gamma-ray dose-rate monitors in which fifteen establishments in the UK participated. The exercise involved the circulation of three gamma-ray monitors for calibration in the fields produced using sup 1 sup 3 sup 7 Cs, sup 2 sup 4 sup 1 Am and sup 6 sup 0 Co. The instruments used were an Electra with MC 20 probe, a Mini-Instruments Mini-rad 1000 and a Siemens electronic personal dosemeter Mk 2 (EPD). The responses relative to 'true' dose equivalent rate were calculated by the individual participants and submitted to the for analysis along with details of the facilities and fields employed. Details of the estimated uncertainties were also reported. The results are compared and demonstrate generally satisfactory agreement between the participating establishments. However, the participants' treatment of uncertainties needs improvement and demonstrates a need for guidance in this area.

  6. Survey of Gamma Dose and Radon Exhalation Rate from Soil Surface of High Background Natural Radiation Areas in Ramsar, Iran

    Directory of Open Access Journals (Sweden)

    Rouhollah Dehghani

    2013-09-01

    Full Text Available Background: Radon is a radioactive gas and the second leading cause of death due to lung cancer after smoking. Ramsar is known for having the highest levels of natural background radiation on earth. Materials and Methods: In this research study, 50 stations of high radioactivity areas of Ramsar were selected in warm season of the year. Then gamma dose and radon exhalation rate were measured.Results: Results showed that gamma dose and radon exhalation rate were in the range of 51-7100 nSv/hr and 9-15370 mBq/m2s, respectively.Conclusion: Compare to the worldwide average 16 mBq/m2s, estimated average annual effective of Radon exhalation rate in the study area is too high.

  7. Values of dose and individual of a individual thermoluminescent dosimeter submitted to x and gamma radiations

    International Nuclear Information System (INIS)

    Moraes, Cassiana Viccari de; Pela, Carlos Alberto

    2001-01-01

    The individual monitoring provides information for the control of exposures, and estimates the dose received by individuals. This is an essential tool in personal dosimetry. It's based on a radiation protection concept, allowing an individual exposure control, besides guaranteeing that the dose restrictions will not be exceeded. Usually, the dose monitoring is performed by using an individual dosemeter placed on a representative position of the most exposed point on the thoracic surface. The dosemeter, which is analyzed in the present work, is made of three CaSO 4 -Dy thermoluminescent detectors, plastic filters, copper and copper-lead, mounted in an acrylic support. The dose received by on each detector, which forms the dosemeter, is related according to their energetic curve dependence. The dose amount is calculated from these curves by using an algorithm, and it was taken in to consideration the detector calibration and thermoluminescent responses, due to the x and g radiation exposure. That algorithm has the capacity to determine the energies that were irradiated the detector. Therefore, to aid the service in the moment of evaluate the dose received by the individual and where it is coming from. The algorithm has provided individual dose value H x , defined as operational quantity for photons adopted in the Brazilian Metric System. The algorithm can determine two dose values and such values have been analyzed according to the kind of irradiated energy on the dosimeter and it has shown that both values are within established limits by Instituto de Radioprotecao e Dosimetria (IRD). (author)

  8. Estimation of the committed radiation dose resulting from gamma radionuclides ingested with food

    International Nuclear Information System (INIS)

    Piotr Godyn; Agnieszka Dolhanczuk-Srodka; Zbigniew Ziembik; Ewa Moliszewska

    2014-01-01

    The objective of the study was to estimate the value of the radiation dose absorbed in consequence of consumption of popular food products for individual age groups. Potatoes, corn and sugar beet were selected for the study. Edible parts of these plants were collected in experimental fields of the KWS Lochow Polska Sp. z o.o. seeding company in Kondratowice (Poland). On the basis of the obtained study results, it can be stated that in consequence of consumption of the selected food products, people may receive increased doses from both natural and artificial radioactive isotopes. The doses calculated for several age groups do not show any health hazards in consequence of consumption of the tested food. One of the determined radionuclides was 137 Cs; however, its presence in the absorbed dose is lower than the doses from natural radioactive isotopes, in particular 40 K. (author)

  9. Genotoxic effects of high dose rate X-ray and low dose rate gamma radiation in ApcMin/+ mice.

    Science.gov (United States)

    Graupner, Anne; Eide, Dag M; Brede, Dag A; Ellender, Michele; Lindbo Hansen, Elisabeth; Oughton, Deborah H; Bouffler, Simon D; Brunborg, Gunnar; Olsen, Ann Karin

    2017-10-01

    Risk estimates for radiation-induced cancer in humans are based on epidemiological data largely drawn from the Japanese atomic bomb survivor studies, which received an acute high dose rate (HDR) ionising radiation. Limited knowledge exists about the effects of chronic low dose rate (LDR) exposure, particularly with respect to the application of the dose and dose rate effectiveness factor. As part of a study to investigate the development of colon cancer following chronic LDR vs. acute HDR radiation, this study presents the results of genotoxic effects in blood of exposed mice. CBAB6 F1 Apc +/+ (wild type) and Apc Min/+ mice were chronically exposed to estimated whole body absorbed doses of 1.7 or 3.2 Gy 60 Co-γ-rays at a LDR (2.2 mGy h -1 ) or acutely exposed to 2.6 Gy HDR X-rays (1.3 Gy min -1 ). Genotoxic endpoints assessed in blood included chromosomal damage (flow cytometry based micronuclei (MN) assay), mutation analyses (Pig-a gene mutation assay), and levels of DNA lesions (Comet assay, single-strand breaks (ssb), alkali labile sites (als), oxidized DNA bases). Ionising radiation (ca. 3 Gy) induced genotoxic effects dependent on the dose rate. Chromosomal aberrations (MN assay) increased 3- and 10-fold after chronic LDR and acute HDR, respectively. Phenotypic mutation frequencies as well as DNA lesions (ssb/als) were modulated after acute HDR but not after chronic LDR. The Apc Min/+ genotype did not influence the outcome in any of the investigated endpoints. The results herein will add to the scant data available on genotoxic effects following chronic LDR of ionising radiation. Environ. Mol. Mutagen. 58:560-569, 2017. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.

  10. Dose Distribution of Gamma Irradiators

    International Nuclear Information System (INIS)

    Park, Seung Woo; Shin, Sang Hun; Son, Ki Hong; Lee, Chang Yeol; Kim, Kum Bae; Jung, Hai Jo; Ji, Young Hoon

    2010-01-01

    Gamma irradiator using Cs-137 have been widely utilized to the irradiation of cell, blood, and animal, and the dose measurement and education. The Gamma cell 3000 Elan (Nordion International, Kanata, Ontario, Canada) irradiator was installed in 2003 with Cs-137 and dose rate of 3.2 Gy/min. And the BioBeam 8000 (Gamma-Service Medical GmbH, Leipzig, Germany) irradiator was installed in 2008 with Cs-137 and dose rate of 3.5 Gy/min. Our purpose was to evaluate the practical dosimetric problems associated with inhomogeneous dose distribution within the irradiated volume in open air state using glass dosimeter and Gafchromic EBT film dosimeter for routine Gamma irradiator dosimetry applications at the KIRAMS and the measurements were compared with each other. In addition, an user guideline for useful utilization of the device based on practical dosimetry will be prepared. The measurement results of uniformity of delivered dose within the device showed variation more than 14% between middle point and the lowest position at central axis. Therefore, to maintain dose variation within 10%, the criteria of useful dose distribution, for research radiation effects, the irradiated specimen located at central axis of the container should be placed within 30 mm from top and bottom surface, respectively. In addition, for measurements using the film, the variations of dose distribution were more then 50% for the case of less than 10 second irradiation, mostly within 20% for the case of more than 20 second irradiation, respectively. Therefore, the irradiation experiments using the BioBeam 8000 irradiator are recommended to be used for specimen required at least more than 20 second irradiation time.

  11. Characterizing dose response relationships: Chronic gamma radiation in Lemna minor induces oxidative stress and altered polyploidy level.

    Science.gov (United States)

    Van Hoeck, Arne; Horemans, Nele; Van Hees, May; Nauts, Robin; Knapen, Dries; Vandenhove, Hildegarde; Blust, Ronny

    2015-12-01

    The biological effects and interactions of different radiation types in plants are still far from understood. Among different radiation types, external gamma radiation treatments have been mostly studied to assess the biological impact of radiation toxicity in organisms. Upon exposure of plants to gamma radiation, ionisation events can cause, either directly or indirectly, severe biological damage to DNA and other biomolecules. However, the biological responses and oxidative stress related mechanisms under chronic radiation conditions are poorly understood in plant systems. In the following study, it was questioned if the Lemna minor growth inhibition test is a suitable approach to also assess the radiotoxicity of this freshwater plant. Therefore, L. minor plants were continuously exposed for seven days to 12 different dose rate levels covering almost six orders of magnitude starting from 80 μGy h(-1) up to 1.5 Gy h(-1). Subsequently, growth, antioxidative defence system and genomic responses of L. minor plants were evaluated. Although L. minor plants could survive the exposure treatment at environmental relevant exposure conditions, higher dose rate levels induced dose dependent growth inhibitions starting from approximately 27 mGy h(-1). A ten-percentage growth inhibition of frond area Effective Dose Rate (EDR10) was estimated at 95 ± 7 mGy h(-1), followed by 153 ± 13 mGy h(-1) and 169 ± 12 mGy h(-1) on fresh weight and frond number, respectively. Up to a dose rate of approximately 5 mGy h(-1), antioxidative enzymes and metabolites remained unaffected in plants. A significant change in catalase enzyme activity was found at 27 mGy h(-1) which was accompanied with significant increases of other antioxidative enzyme activities and shifts in ascorbate and glutathione content at higher dose rate levels, indicating an increase in oxidative stress in plants. Recent plant research hypothesized that environmental genotoxic stress conditions

  12. Determination of gamma radiation dose for destruction of Salmonella spp. in chicken flesh

    International Nuclear Information System (INIS)

    Santos, Andreia Ferreira dos

    1997-01-01

    The aim of this study was to determinate: 1) the radio sensibility of Salmonella typhimurium ATCC 14028 in soy trypticase broth; 2) the radio sensibility of Salmonella typhimurium ATCC 14028 in chicken thigh and; 3) to recommend a radiation dose which can be non hazardous for human consumption

  13. Indoor gamma radiation dose levels in West Bengal using passive dosimeters

    International Nuclear Information System (INIS)

    Shetty, P.G.; Sahu, S.K.; Swarnkar, M.; Takale, R.A.; Pandit, G.G.

    2016-01-01

    Geography of West Bengal, a state in eastern India, is diverse, of high peaks of Himalaya in the northern extremes to coastal regions down south, with regions such as plateau and Ganges delta intervening in between. West Bengal is only state in India where Himalayas are in the north and Sea is at the south, with both plains and plateaus covering the remaining region. West Bengal is divided into three main divisions known as the Jalpaiguri division, Burdwan division and the Presidency division. It shows the district map of West Bengal. The result of preliminary indoor gamma radiation monitoring carried out in different districts of West Bengal is given in this paper

  14. Low gamma radiation dose effect on germination and initial growing of black beans (Phaseolus vulgaris L.) seeds

    International Nuclear Information System (INIS)

    Jesus, Edgar F.O. de; Silva, Anderson de O. Melo; Marsico, Eliane T.

    2005-01-01

    In this work we analyze the effect of low gamma irradiation doses and low concentrations of sodium alginate on the germination and growing of black beans seeds. The seeds were obtained from an organic farmer at Nova Friburgo, Rio de Janeiro State. The seeds were submitted to radiation doses between 0 and 150 Gy with a Cobalt 60 source in a Gammacell Excel 220 Nordion Irradiator with a dose rate of 70 Gy/min. After germination the seeds were left to grow three weeks on a hydroponics system. The system used was the water culture with nutritive solution that was supplemented with the nutritional needs for plant grows. We also tested the influence of the sodium alginate on the plant grows. A 4% solution of sodium alginate in distilled water was irradiated with 120 kGy gamma ray dose. Concentrations of sodium alginate irradiated and non-irradiated varying from 50 to 500 μg/g were used in the hydroponics' solution. After three weeks the mass and the height of the plant were measured. Statistic analyses of he result with the SAS program show that there was no significant difference between the height and mass of seeds submitted different doses, but irradiated solution of sodium alginate with concentration of 400 and 500 μg/g present a significant difference on plant grow. (author)

  15. New routes of preparation of polyaniline films and dosimetric characterization for high-doses gamma radiation

    International Nuclear Information System (INIS)

    Pacheco, Ana Paula Lima

    2003-08-01

    This work presents a new conducting polymeric material based on polyaniline thin films that will be used in the confection of dosimetric devices. On preparation of the films a homogeneous and viscous solution of poly (acrylic acid) and MnO 2 is deposited on PMMA surface, which after dried, is immersed in an acid aniline solution. The films formed present low resistivity (6.10 2 Ωm), good mechanical resistance and adherence on the electrodes. The films were characterized by infrared spectroscopy, conductivity measurements and manganese elemental analyses. The resistance variations show linear correlation (r 2 = 0,9928) with gamma irradiation dose in the range of 1000 to 6000 Gy, with medium error less than 5% and sensitivity response. The dosimetric devices present as advantage real time measurements, low cost, use in calibration of industrial radioactive sources. Moreover, this composite could in future replace Fricke dosimeter and its applications. A calibration curve is showed for PANI dosimeter, here proposed, to use at high gamma doses. (author)

  16. Dose-rate and humidity effects upon the gamma-radiation response of nylon-based radiachromic film dosimeters

    International Nuclear Information System (INIS)

    Gehringer, P.; Eschweiler, H.; Proksch, E.

    1979-10-01

    At dose-rates typical for 60 Co gamma irradiation sources, the radiation response of hexahydroxyethyl pararosaniline cyanide/ 50μm nylon radiachromic films is dependent upon dose-rate as well as upon the moisture content of the films, or the relative humidity of the surrounding atmosphere, respectively. Under equilibrium moisture conditions, the response measured at 606 nm 24 hours after end of irradiation shows its highest dose-rate dependence at about 32 % r.h. A decrease in dose-rate from 2.8 to 0.039 Gy.s -1 results in a decrease in response by 17%. At higher humidities, the sensitivity of the film as well as the rate dependence decreases and at 86% r.h. no discernible dose-rate effect could be found. At lower humidities than 32% a flat maximum in response follows. At nominal 0% r.h. a second absorption band at 412 nm appears which is converted completely to an additional 606 nm absorption by exposure to a humid atmosphere. After that procedure the resultant response is somewhat lower than but shows almost the same dose-rate dependence as at 32% r.h. or else to eliminate the dose-rate effect by an extrapolation procedure based on the fact that the rate dependence vanishes at zero dose. (author)

  17. Influence of dose on particle size of colloidal silver nanoparticles synthesized by gamma radiation

    International Nuclear Information System (INIS)

    Naghavi, Kazem; Saion, Elias; Rezaee, Khadijeh; Yunus, Wan Mahmood Mat

    2010-01-01

    Colloidal silver nanoparticles were synthesized by γ-irradiation-induced reduction method of an aqueous solution containing silver nitrate as a precursor in various concentrations between 7.40x10 -4 and 1.84x10 -3 M, polyvinyl pyrrolidone for capping colloidal nanoparticles, isopropanol as radical scavenger of hydroxyl radicals and deionised water as a solvent. The irradiations were carried out in a 60 Co γ source chamber at doses up to 70 kGy. The optical absorption spectra were measured using UV-vis spectrophotometer and used to study the particle distribution and electronic structure of silver nanoparticles. As the radiation dose increases from 10 to 70 kGy, the absorption intensity increases with increasing dose. The absorption peak λ max blue shifted from 410 to 403 nm correspond to the increase of absorption conduction electron energy from 3.02 to 3.08 eV, indicating the particle size decreases with increasing dose. The particle size was determined by photon cross correlation spectroscopy and the results showed that the particle diameter decreases exponentially with the increase of dose. The transmission electron microscopy images were taken at doses of 20 and 60 kGy and the results confirmed that as the dose increases the diameter of colloidal silver nanoparticle decreases and the particle distribution increases.

  18. Immunobiological, biochemical and physico-chemical characteristics of Brucella lipopolysaccharide subjected to various doses of gamma radiation

    International Nuclear Information System (INIS)

    Dranovskaya, E.A.; Shibaeva, I.V.

    1975-01-01

    A comparative study is presented of toxicity, serological activity, some biochemical and physico-chemical properties of the highly toxic Brucella lipopolysaccharide (LPS) and of preparations obtained as a result of gamma irradiation in doses of 1, 3, and 10 mrad on the antigen. The toxicity of LPS was found to decrease with increasing radiation dose. Irradiation with a dose of 3 mrad produced a marked decrease in the toxicity of the antigen without essentially changing its serological properties. The process of LPS detoxication under the effect of irradiation was accompanied by changes in certain biochemical and physico-chemical indices suggestive of a modification of the primary structure of the LPS molecule and of an impairment especially of its polysaccharide side chains. (author)

  19. Immunobiological, biochemical, and physico-chemical characteristics of Brucella lipopolysaccharide subjected to various doses of gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dranovskaya, E A; Shibaeva, I V [Akademiya Meditsinskikh Nauk SSSR, Moscow. Inst. Ehpidemiologii i Mikrobiologii; Khabakpasheva, N A; Rostovtseva, N A [Institut Vaktsin i Syvorotok, Moscow (USSR)

    1975-01-01

    A comparative study is presented of toxicity, serological activity, some biochemical and physico-chemical properties of the highly toxic Brucella lipopolysaccharide (LPS) and of preparations obtained as a result of gamma irradiation in doses of 1, 3, and 10 mrad on the antigen. The toxicity of LPS was found to decrease with increasing radiation dose. Irradiation with a dose of 3 mrad produced a marked decrease in the toxicity of the antigen without essentially changing its serological properties. The process of LPS detoxication under the effect of irradiation was accompanied by changes in certain biochemical and physico-chemical indices suggestive of a modification of the primary structure of the LPS molecule and of an impairment especially of its polysaccharide side chains.

  20. Dose Rate Effect on Grafting by Gamma Radiation of DMAEMA onto Flexible PVC

    International Nuclear Information System (INIS)

    Panzarini, L.C.G.A.; Araujo, F.D.C.; Martinello, V.C.; Somesari, E.; Manzoli, J.E.; Silveira, C.; Paes, H.A.; Moura, E.

    2009-01-01

    Intravenous tubing, blood bags and catheters stays in contact with blood and body fluids. They are normally made by flexible PVC. The contact of PVC with this fluid is not possible for long periods and there is the necessity of addition of non-thrombogenic substances into blood. This work shows the radiation grafting process to produce copolymer PVC-g-DMAEMA, a new material that allows a future grafting of Heparin on it, and will have the perspective of avoiding undesirable substances additions to blood or body fluid contact. In this preliminary work, only radiation dose rate effect on grafting was studied

  1. Characterizing dose response relationships: Chronic gamma radiation in Lemna minor induces oxidative stress and altered polyploidy level

    International Nuclear Information System (INIS)

    Van Hoeck, Arne; Horemans, Nele; Van Hees, May; Nauts, Robin; Knapen, Dries; Vandenhove, Hildegarde; Blust, Ronny

    2015-01-01

    The biological effects and interactions of different radiation types in plants are still far from understood. Among different radiation types, external gamma radiation treatments have been mostly studied to assess the biological impact of radiation toxicity in organisms. Upon exposure of plants to gamma radiation, ionisation events can cause, either directly or indirectly, severe biological damage to DNA and other biomolecules. However, the biological responses and oxidative stress related mechanisms under chronic radiation conditions are poorly understood in plant systems. In the following study, it was questioned if the Lemna minor growth inhibition test is a suitable approach to also assess the radiotoxicity of this freshwater plant. Therefore, L. minor plants were continuously exposed for seven days to 12 different dose rate levels covering almost six orders of magnitude starting from 80 μGy h"−"1 up to 1.5 Gy h"−"1. Subsequently, growth, antioxidative defence system and genomic responses of L. minor plants were evaluated. Although L. minor plants could survive the exposure treatment at environmental relevant exposure conditions, higher dose rate levels induced dose dependent growth inhibitions starting from approximately 27 mGy h"−"1. A ten-percentage growth inhibition of frond area Effective Dose Rate (EDR_1_0) was estimated at 95 ± 7 mGy h"−"1, followed by 153 ± 13 mGy h"−"1 and 169 ± 12 mGy h"−"1 on fresh weight and frond number, respectively. Up to a dose rate of approximately 5 mGy h"−"1, antioxidative enzymes and metabolites remained unaffected in plants. A significant change in catalase enzyme activity was found at 27 mGy h"−"1 which was accompanied with significant increases of other antioxidative enzyme activities and shifts in ascorbate and glutathione content at higher dose rate levels, indicating an increase in oxidative stress in plants. Recent plant research hypothesized that environmental genotoxic

  2. Effect of Low Dose Gamma Radiation Upon the Concentration of Calcium and Inorganic Phosphorus in the Blood Plasma of Chickens

    International Nuclear Information System (INIS)

    Kraljevic, P.; Vilic, M.; Miljanic, S.; Simpraga, M.

    2003-01-01

    In our previous paper it has been showed that the irradiation of chickens eggs before incubation by low dose gamma irradiation effects upon growth of the chickens hatched from irradiated eggs as well as upon activity of ALT and AST, and on the concentration of total proteins, glucose and cholesterol in the blood plasma of those chickens. Therefore in this paper an attempt was made to determine the effects of irradiation of eggs by low dose of ionizing radiation on the 19th day of incubation upon the concentration of calcium (Ca) and inorganic phosphorus (P) in the blood plasma of chickens hatched from irradiated eggs. The eggs of heavy breeding chickens (Gent, line COBB 500) were irradiated by a dose of 0.15 Gy gamma radiation (6 0C o source) on the 19th day of incubation. Along with the chickens, which were hatched from irradiated eggs, there was a control group of chickens hatched from nonirradiated eggs. All other conditions were the same for both groups. After hatching, blood samples were taken on day 1, 3, 5, 7, 10, 20, 30 and 42. The concentration of Ca was determined calorimetrically using Randox optimized kits, while the concentration of P was determined by Herbos dijagnostika Sisak (Croatia) optimized kits. The concentration of Ca in the blood plasma of chickens hatched from irradiated eggs was significantly increased on the first day, while it was decreased on the day 42. The concentration of P was decreased on the first day in blood plasma of chickens hatched from irradiated eggs. The fact that the concentration of both minerals in blood plasma of chickens hatched from irradiated eggs was significantly changed on the first day proves that the irradiation of eggs by low dose of ionizing radiation on the nineteenth day of incubation had an effect on metabolism of both minerals in those chickens. (author)

  3. Concentration of total proteins in blood plasma of chickens hatched from irradiated eggs with low dose gamma radiation

    International Nuclear Information System (INIS)

    Vilic, M.; Kraljevic, P.; Miljanic, S.; Simpraga, M.

    2005-01-01

    It is known that low-dose ionising radiation may have stimulating effects on chickens. Low doses may also cause changes in the concentration of blood plasma total proteins, glucose and cholesterol in chickens. This study investigates the effects of low dose gamma-radiation on the concentration of total proteins in the blood plasma of chickens hatched from eggs irradiated with a dose of 0.15 Gy on incubation days 7 and 19. Results were compared with the control group (chickens hatched from non-irradiated eggs). After hatching, all other conditions were the same for both groups. Blood samples were drawn from the heart, and later from the wing vein on days 1, 3, 5, 7,10, 20, 30 and 42. The concentration of total proteins was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. The concentration of total proteins in blood plasma in chickens hatched from eggs irradiated with 0.15 Gy on incubation day 7 showed a statistically significant decrease on the sampling day 3 (P less than 0.05) and 7 (P less than 0.01). The concentration of total proteins in blood plasma in chickens hatched from eggs irradiated with 0.15 Gy on incubation day 19 showed a statistically significant increase only on sampling day 1 (P less than 0.05). These results suggest that exposure of eggs to 0.15 Gy of gamma-radiation on the 7th and 19th day of incubation could produce different effects on the protein metabolism in chickens.(author)

  4. Radiation doses to Finns

    International Nuclear Information System (INIS)

    Rantalainen, L.

    1996-01-01

    The estimated annual radiation doses to Finns have been reduced in the recent years without any change in the actual radiation environment. This is because the radiation types have been changed. The risk factors will probably be changed again in the future, because recent studies show discrepancies in the neutron dosimetry concerning the city of Hiroshima. Neutron dosimetry discrepancy has been found between the predicted and estimated neutron radiation. The prediction of neutron radiation is calculated by Monte Carlo simulations, which have also been used when designing recommendations for the limits of radiation doses (ICRP60). Estimation of the neutron radiation is made on the basis of measured neutron activation of materials in the city. The estimated neutron dose beyond 1 km is two to ten, or more, times as high as the predicted dose. This discrepancy is important, because the most relevant distances with respect to radiation risk evaluation are between 1 and 2 km. Because of this discrepancy, the present radiation risk factors for gamma and neutron radiation, which rely on the Monte Carlo calculations, are false, too. The recommendations of ICRP60 have been adopted in a few countries, including Finland, and they affect the planned common limits of the EU. It is questionable whether happiness is increased by adopting false limits, even if they are common. (orig.) (2 figs., 1 tab.)

  5. Crystal growth and thermoluminescence response of NaZr{sub 2}(PO{sub 4}){sub 3} at high gamma radiation doses

    Energy Technology Data Exchange (ETDEWEB)

    Ordóñez-Regil, E., E-mail: eduardo.ordonez@inin.gob.mx [Depto. de Química, Gerencia de Ciencias Básicas, Instituto Nacional de Investigaciones Nucleares, AP 18-1027, CP 11801 México D.F. (Mexico); Contreras-Ramírez, A., E-mail: aida.contreras@inin.gob.mx [Depto. de Química, Gerencia de Ciencias Básicas, Instituto Nacional de Investigaciones Nucleares, AP 18-1027, CP 11801 México D.F. (Mexico); Depto. de Tecnología de Materiales, Gerencia de Ciencias Aplicadas, Instituto Nacional de Investigaciones Nucleares, AP 18-1027, CP 11801 México D.F. (Mexico); Facultad de Ciencias, Universidad Autónoma del Estado de México, Unidad Académica el Cerrillo, Piedras Blancas, AP 2-139, CP 50000 Toluca Estado de México (Mexico); Fernández-Valverde, S.M., E-mail: suilma.fernandez@inin.gob.mx [Depto. de Química, Gerencia de Ciencias Básicas, Instituto Nacional de Investigaciones Nucleares, AP 18-1027, CP 11801 México D.F. (Mexico); González-Martínez, P.R., E-mail: pedro.gonzalez@inin.gob.mx [Depto. de Física, Gerencia de Ciencias Básicas, Instituto Nacional de Investigaciones Nucleares, AP 18-1027, CP 11801 México D.F. (Mexico); Carrasco-Ábrego, H., E-mail: hector.carrasco@inin.gob.mx [Depto. Aceleradores, Gerencia de Ciencias Ambientales, Instituto Nacional de Investigaciones Nucleares, AP 18-1027, CP 11801 México D.F. (Mexico)

    2013-11-15

    Graphical abstract: -- Highlights: •NaZr{sub 2}(PO{sub 4}){sub 3} exposed to gamma doses of 10, 30 and 50 MGy. •Gamma radiation produced growth of the crystal size of the NZP. •Morphology changes were reversible by heating. •Linear relationship between the thermoluminescence and the applied gamma dose. •This property could be useful for high-level gamma dosimetry. -- Abstract: This work describes the synthesis and characterization of NaZr{sub 2}(PO{sub 4}){sub 3}. The stability of this material under high doses of gamma radiation was investigated in the range of 10–50 MGy. Samples of unaltered and gamma irradiated NaZr{sub 2}(PO{sub 4}){sub 3} were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and thermoluminescence. The results showed that while functional groups were not affected by the gamma irradiation, morphology changes were observed with increasing doses of gamma irradiation. The morphology of the non-irradiated compound is agglomerated flakes; however, irradiation at 10 MGy splits the flakes inducing the formation of well-defined cubes. Gamma irradiation induced the crystal size of the NaZr{sub 2}(PO{sub 4}){sub 3} to grow. The heat treatment (973 K) of samples irradiated at 50 MGy resulted in the recovery of the original morphology. Furthermore, the thermoluminescence analysis of the irradiated compound is reported.

  6. Radiation-induced bystander effects in the Atlantic salmon (salmo salar L.) following mixed exposure to copper and aluminum combined with low-dose gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mothersill, Carmel; Seymour, Colin B. [McMaster University, Medical Physics and Applied Radiation Sciences Department, Hamilton, ON (Canada); Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, Aas (Norway); Smith, Richard W. [McMaster University, Medical Physics and Applied Radiation Sciences Department, Hamilton, ON (Canada); Heier, Lene Soerlie; Teien, Hans-Christian; Land, Ole Christian; Oughton, Deborah; Salbu, Brit [Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, Aas (Norway)

    2014-03-15

    Very little is known about the combined effects of low doses of heavy metals and radiation. However, such ''multiple stressor'' exposure is the reality in the environment. In the work reported in this paper, fish were exposed to cobalt 60 gamma irradiation with or without copper or aluminum in the water. Doses of radiation ranged from 4 to 75 mGy delivered over 48 or 6 h. Copper doses ranged from 10 to 80 μg/L for the same time period. The aluminum dose was 250 μg/L. Gills and skin were removed from the fish after exposure and explanted in tissue culture flasks for investigation of bystander effects of the exposures using a stress signal reporter assay, which has been demonstrated to be a sensitive indicator of homeostatic perturbations in cells. The results show complex synergistic interactions of radiation and copper. Gills on the whole produce more toxic bystander signals than skin, but the additivity scores show highly variable results which depend on dose and time of exposure. The impacts of low doses of copper and low doses of radiation are greater than additive, medium levels of copper alone have a similar level of effect of bystander signal toxicity to the low dose. The addition of radiation stress, however, produces clear protective effects in the reporters treated with skin-derived medium. Gill-derived medium from the same fish did not show protective effects. Radiation exposure in the presence of 80 μg/L led to highly variable results, which due to animal variation were not significantly different from the effect of copper alone. The results are stressor type, stressor concentration and time dependent. Clearly co-exposure to radiation and heavy metals does not always lead to simple additive effects. (orig.)

  7. Natural terrestrial radiation exposure in Hong Kong. A survey on environmental gamma absorbed dose rate in air

    International Nuclear Information System (INIS)

    Wong, M.C.; Poon, H.T.; Chan, Y.K.; So, C.K.

    2000-01-01

    Hong Kong is a metropolitan city located on the southern coast of China with a population of some six million. About 90% of the population is concentrated in heavily built-up residential and commercial areas, which accounts for less than 50% of the total area in the territory. Hong Kong Observatory, 134A Nathan Road, Kowloon, Hong Kong, China. In order to understand the spatial variations in the environmental radiation levels in Hong Kong, the Hong Kong Observatory (HKO) in early 1999 conducted a study of the environmental gamma absorbed dose rate in air. The study combined data collected by the HKO radiation monitoring network (RMN) and data from a comprehensive territory-wide radiological survey conducted in January and February 1999. The RMN of ten stations each equipped with a Reuter-Stokes Model RSS-1013 HPIC has been in operation since 1987 to continuously monitor the environmental radiation levels over the territory as part of the emergency monitoring programme for response to nuclear accidents at a nearby nuclear power station. The terrestrial component of the environmental radiation field was estimated by subtracting from the measurements the cosmic contribution, which is determined to be about 39 nGy/h from measurements conducted over two large fresh water reservoirs. The RMN data with the long history was analysed to derive the seasonal variations in the environmental radiation levels. On average the environmental gamma absorbed dose rate in air in January and February is 1.03 times of the annual figure. This seasonal correction was applied to the results of the year 1999 survey. As the radiation field in the heavily built-up areas is enhanced by contribution from buildings, in the territory-wide survey measurements were made both in the open field and built-up areas. The territory of Hong Kong was divided into 42 grid boxes of 5 km x 5 km for open field and 61 grid boxes of 2.5 km x 2.5 km for built-up areas according to the population and land use. A

  8. Effects of low dose {gamma} radiation on early growth and physiological activities of radish (raphanus sativus L.) and the reduction of ultraviolet-B stress

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. S.; Lee, Y. K.; Lee, H. Y.; Baek, M. H.; Yoo, J. C. [KAERI, Taejon (Korea, Republic of)

    2002-10-01

    The effect of low dose {gamma} radiation on early growth and photosynthesis in radish plant was studied. The seedling height of radish was stimulated in plants grown from seeds irradiated with the low dose of 10 Gy. The O{sub 2} evolution in the 10 Gy irradiation group was 1.2 times greater than in the control. The catalase and peroxidase activity of radish leaves grown from seeds irradiated with {gamma} radiation were increased at 10 Gy irradiation group as the superoxide dismutase activity of leaves was. To investigate the effect of low dose {gamma} radiation on response to UV-B stress, UV-B was given at the intensity of 1 W{center_dot} m{sup -2} to the detached leaves. Pmax was decreased with increasing illumination time by 76% in the control, while decreased by 75% in the 10 Gy irradiation group. The photochemical yield of PSII, estimated as Fv/Fm, was decreased with increasing illumination time by 75% after 4 hours while Fv/Fm in the 10 Gy irradiation group was decreased by 69% of inhibition, indicating that the low dose {gamma} radiation retarded the deteriorative effect of UV-B on PSII. The initial fluorescence (Fo) was slightly increased with increasing illumination time, while the maximal fluorescence (Fm) was decreased. These results showed the positive effect of low dose {gamma} radiation on the seedling growth and the reduction of the deteriorative effect of UV-B stress on photosynthesis in radish plant.

  9. Determination of effective dose in anisotropic gamma radiation fields: application of dosimeters calibrated in terms of Hp(10)

    International Nuclear Information System (INIS)

    Chumak, V. V.; Bakhanova, E. V.

    2003-01-01

    In this presentation authors deals with determination of effective dose in anisotropic gamma radiation fields. It was conclude that: - Straightforward application of Hp(10) as surrogate for E may not work under certain conditions; - Partial data on behavior of E and Hp(10) for different dosimeters allow to estimate E/Hp(10) conversion coefficients for any particular composite source; - In practical situations, anisotropy of workplace fields may be measured by six- collimator device assessing contribution to a dose from six orthogonal directions; - Reasonably conservative conversion coefficients may be assessed for given energy spectrum and degree of anisotropy of workplace fields; - For strongly anisotropic fields multiple dosimetry approach gives the best estimate of E comparing to plain Hp(10) readouts or integral conversion coefficients

  10. Determination of gamma radiation dose as a post-harvest treatment in mangos infested with the South American fruit fly

    International Nuclear Information System (INIS)

    Alama, D.

    1999-01-01

    Efforts are being made to determine a gamma radiation dose for mortality of third-instar larvae of Anastrepha fraterculus which infest mangos of the Haden variety of 400 g weight. Four radiation treatments were tested: 0.4 kGy, 0.6 kGy, 0.8 kGy and 1.0 kGy. Using as a criterium for mortality the interruption of the biological cycle between larva and pupa, the following results were achieved: 49.61%, 63.33%, 74.86% and 90.72%. The percentages obtained have been corrected using the Abbot formula. When the criterium was based on no adult emergence, 100% mortality was achieved for the four treatments. (author)

  11. Gamma Low-Dose-Rate Ionizing Radiation Stimulates Adaptive Functional and Molecular Response in Human Aortic Endothelial Cells in a Threshold-, Dose-, and Dose Rate-Dependent Manner.

    Science.gov (United States)

    Vieira Dias, Juliana; Gloaguen, Celine; Kereselidze, Dimitri; Manens, Line; Tack, Karine; Ebrahimian, Teni G

    2018-01-01

    A central question in radiation protection research is whether low-dose and low-dose-rate (LDR) exposures to ionizing radiation play a role in progression of cardiovascular disease. The response of endothelial cells to different LDR exposures may help estimate risk of cardiovascular disease by providing the biological mechanism involved. We investigated the effect of chronic LDR radiation on functional and molecular responses of human aorta endothelial cells (HAoECs). Human aorta endothelial cells were continuously irradiated at LDR (6 mGy/h) for 15 days and analyzed at time points when the cumulative dose reached 0.05, 0.5, 1.0, and 2.0 Gy. The same doses were administered acutely at high-dose rate (HDR; 1 Gy/min). The threshold for the loss of angiogenic capacity for both LDR and HDR radiations was between 0.5 and 1.0 Gy. At 2.0 Gy, angiogenic capacity returned to normal only for HAoEC exposed to LDR radiation, associated with increased expression of antioxidant and anti-inflammatory genes. Pre-LDR, but not pre-HDR, radiation, followed by a single acute 2.0 Gy challenge dose sustained the expression of antioxidant and anti-inflammatory genes and stimulated angiogenesis. Our results suggest that dose rate is important in cellular response and that a radioadaptive response is involved for a 2.0 Gy dose at LDR.

  12. Gamma Low-Dose-Rate Ionizing Radiation Stimulates Adaptive Functional and Molecular Response in Human Aortic Endothelial Cells in a Threshold-, Dose-, and Dose Rate–Dependent Manner

    Science.gov (United States)

    Vieira Dias, Juliana; Gloaguen, Celine; Kereselidze, Dimitri; Manens, Line; Tack, Karine; Ebrahimian, Teni G

    2018-01-01

    A central question in radiation protection research is whether low-dose and low-dose-rate (LDR) exposures to ionizing radiation play a role in progression of cardiovascular disease. The response of endothelial cells to different LDR exposures may help estimate risk of cardiovascular disease by providing the biological mechanism involved. We investigated the effect of chronic LDR radiation on functional and molecular responses of human aorta endothelial cells (HAoECs). Human aorta endothelial cells were continuously irradiated at LDR (6 mGy/h) for 15 days and analyzed at time points when the cumulative dose reached 0.05, 0.5, 1.0, and 2.0 Gy. The same doses were administered acutely at high-dose rate (HDR; 1 Gy/min). The threshold for the loss of angiogenic capacity for both LDR and HDR radiations was between 0.5 and 1.0 Gy. At 2.0 Gy, angiogenic capacity returned to normal only for HAoEC exposed to LDR radiation, associated with increased expression of antioxidant and anti-inflammatory genes. Pre-LDR, but not pre-HDR, radiation, followed by a single acute 2.0 Gy challenge dose sustained the expression of antioxidant and anti-inflammatory genes and stimulated angiogenesis. Our results suggest that dose rate is important in cellular response and that a radioadaptive response is involved for a 2.0 Gy dose at LDR. PMID:29531508

  13. Effect of Fractionated Low Doses of Gamma Radiation on Some Haematological and Immunological Parameters in Albino Rat

    International Nuclear Information System (INIS)

    Bahgat, M.M.; Abdel-Khalek, L.G.

    2003-01-01

    This study was performed on 30 mature male albino rats to evaluate the direct effect of fractionated low doses (0.5 Gy twice weekly) gamma radiation and delayed effect (one month post-irradiation) on some haematological and immunological parameters. The rats were divided into three equal groups, Control and two whole body gamma-irradiated groups the irradiated groups were subjected to total doses of 4 and 8 Grays over a period of one and two months, respectively. The blood samples and peritoneal macrophages were taken twice from each irradiated rats at the end of their irradiation period and after one month post irradiation. Activated peritoneal macrophages in all groups showed significant decrease as compared to control group denoting that irradiation may cause receptor alteration and/or decrease in the phagocytic power of macrophages lasting for a longer time. Throughout the whole experiment there was wide variation in platelet count with no significant or minimal changes in other blood elements. Moreover, in the post irradiation group after two months irradiation, all the haematological parameters tested, except the Hct, were increased as compared to the control group. These results pointed to that the bone marrow and lymphoid organs of the animals can tolerate fractionated low dose irradiation through rapid recovery and/or compensatory stimulation. The presence of many target cells in the post irradiated group increases the red blood cell fragility

  14. Influence of high doses gamma radiation on group of meadow plants and water organisms

    International Nuclear Information System (INIS)

    Wlodek, St.; Wasilewski, A.; Indeka, L.; Kobuszewska, B.; Krzysztofik, B.; Ossowska-Cypryk, K.; Slomczynski, T.

    1979-01-01

    The plot of 100 square meters area has been irradiated for 526 days by gamma radiation which simulated the external radiation of the local fall-out. This field experiment has been performed in specially preserved conditions. The organisms of land and water complexes present in this area have received the total of 50 000 R in the center and 600 R on periphery. It has been shown that: changes in the quantitative and qualitative composition of bacteria and soil and water fungi were generally little: among the physiological groups the greatest disfunctions have been observed for the bacteria of the nitric cycle; Lemna minor appeared to be the most radiosensitive water plant which perished completely in the zone around the center of the plot what in turn resulted in secondary changes in the composition of water microflora and micro- and macrofauna; the growth of 14 species of meadow plants present around the center of the plot has been reduced about 25% of biomass in comparison with the control plots; on the other hand, the stimulation of growth of meadow plants, mostly weeds, has been observed on the periphery of the plot. (author)

  15. Influence of high doses gamma radiation on group of meadow plants and water organisms

    Energy Technology Data Exchange (ETDEWEB)

    Wlodek, St; Wasilewski, A; Indeka, L; Kobuszewska, B; Krzysztofik, B; Ossowska-Cypryk, K; Slomczynski, T

    1979-01-01

    The plot of 100 square meters area has been irradiated for 526 days by gamma radiation which simulated the external radiation of the local fall-out. This field experiment has been performed in specially preserved conditions. The organisms of land and water complexes present in this area have received the total of 50 000 R in the center and 600 R on periphery. It has been shown that: changes in the quantitative and qualitative composition of bacteria and soil and water fungi were generally little: among the physiological groups the greatest disfunctions have been observed for the bacteria of the nitric cycle; Lemna minor appeared to be the most radiosensitive water plant which perished completely in the zone around the center of the plot what in turn resulted in secondary changes in the composition of water microflora and micro- and macrofauna; the growth of 14 species of meadow plants present around the center of the plot has been reduced about 25% of biomass in comparison with the control plots; on the other hand, the stimulation of growth of meadow plants, mostly weeds, has been observed on the periphery of the plot.

  16. Effect of high doses of gamma radiation on thermophysical properties of ZrO2 nanofluids in aqueous base

    International Nuclear Information System (INIS)

    Pinho, Priscila G.M.; Rocha, Marcelo S.

    2017-01-01

    This work conducts a general theoretical and experimental study of the physical properties associated with the heat transfer capacity of ZrO 2 nanofluids in aqueous base and the effects of gamma on such properties, with a view to the possibility of applying as heat transfer fluid in future generations of nuclear reactor systems. The effects of concentrations and temperature, before and after the action of ionizing radiation were carried out. Theoretical models, parameters of influence and experimental results available in specialized literature were reviewed. Experimental study of physical properties of nanofluids samples in various concentrations (0.001% vol. 0.01% vol. 0.1% vol.), without the action of gamma radiation was also conducted. The physical properties investigated are the thermal conductivity, electrical conductivity, pH, density, and viscosity. Nanofluid samples were irradiated in the Multipurpose Radiator of IPEN under the doses 1 MGy, 2 MGy, and 3 MGy. Analysis using techniques of samples visualization before and after irradiation using scanning electron microscope (SEM) was adopted. The trials will be held to display the verification of the change in distribution of nanoparticles after irradiation of samples. This test aims to check for changes in the structure of the nanoparticles. It is expected with the results from this research project, a contribution to the advancement of knowledge of nanofluids applications in high heat transfer systems. (author)

  17. Effect of high doses of gamma radiation on thermophysical properties of ZrO{sub 2} nanofluids in aqueous base

    Energy Technology Data Exchange (ETDEWEB)

    Pinho, Priscila G.M.; Rocha, Marcelo S., E-mail: pri.pgm@gmail.com, E-mail: msrocha@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    This work conducts a general theoretical and experimental study of the physical properties associated with the heat transfer capacity of ZrO{sub 2} nanofluids in aqueous base and the effects of gamma on such properties, with a view to the possibility of applying as heat transfer fluid in future generations of nuclear reactor systems. The effects of concentrations and temperature, before and after the action of ionizing radiation were carried out. Theoretical models, parameters of influence and experimental results available in specialized literature were reviewed. Experimental study of physical properties of nanofluids samples in various concentrations (0.001% vol. 0.01% vol. 0.1% vol.), without the action of gamma radiation was also conducted. The physical properties investigated are the thermal conductivity, electrical conductivity, pH, density, and viscosity. Nanofluid samples were irradiated in the Multipurpose Radiator of IPEN under the doses 1 MGy, 2 MGy, and 3 MGy. Analysis using techniques of samples visualization before and after irradiation using scanning electron microscope (SEM) was adopted. The trials will be held to display the verification of the change in distribution of nanoparticles after irradiation of samples. This test aims to check for changes in the structure of the nanoparticles. It is expected with the results from this research project, a contribution to the advancement of knowledge of nanofluids applications in high heat transfer systems. (author)

  18. Effect of low-dose gamma radiation on HIV replication in human peripheral blood mononuclear cells

    International Nuclear Information System (INIS)

    Xu, Y.; Conway, B.; O'Shaughnessy, M.V.; Greenstock, C.L.

    1996-01-01

    Recent studies have demonstrated that UV light and x-irradiation enhance human immunodeficiency virus (HIV) gene expression. There are few published data on related effects of γ-radiation. This may be of clinical relevance, as radiotherapy has been used extensively for the treatment of acquired immunodeficiency syndrome associated conditions. We have studied the effects of γ-radiation on HIV replication in mono-nuclear cells (MC). These cells were obtained from five seronegative healthy donors, exposed to 0-200 cGy γ-radiation, stimulated with phytohemagglutinin-P (PHA-P) for 24 h, infected with a laboratory strain of HIV (HTLV-IIIB, multiplicity of infection = 0.001), then carried in culture for 14 days. Overall, when considering p24 antigen levels on days 7 and 11 in cultures established from cells exposed to 50 cGy, the maximal levels were significantly higher than those measured in the parallel control cultures taken as a whole (P < 0.05), with viral replication enhanced as much as 1000-fold in one case. No significant cytotoxicity was observed following exposure to doses up to 50 cGy. The mechanism of the observed effect remains unknown but may relate to direct gene activation and/or free radical generation, leading to such activation. To date, there is no evidence that viral stimulation occurs following therapeutic radiation in a clinical setting. (author)

  19. Gamma radiation-induced Impairment of hippocampal neurogenesis, comparison of single and fractionated dose regimens

    International Nuclear Information System (INIS)

    Khoshbin khoshnazar, A. R; Jahanshahi, M; Azami, N. S

    2012-01-01

    Radiation therapy of the brain is associated with many consequences, including cognitive disorders. Pathogenesis of radiation induced cognitive disorder is not clear, but reduction of neurogenesis in hippocampus may be an underlying reason. 24 adult male rats entered to study. Radiation absorbed dose to midbrain was 10 Gy, delivered by routine cobalt radiotherapy machine which its output was measured 115.24 cGy/min. The rats were divided in four groups of sixes, including groups of control, single fraction 10 Gy, fractionated 10 Gy and finally anaesthesia sham group. Number of pyramidal nerve cells was counted in two regions of hippocampus formation (CA1 and CA3). The radiation could reduce the number of cells in two regions of hippocampus significantly (p=0.000). It seems fractionated 10 Gy irradiation to more efficient than single fraction, while role of anaesthesia drug should be cautiously assessed. Moreover the rate of neurogenesis reduction was determined the same in these regions of hippocampus meaning the same radiosensitivity of cells

  20. Dose and dose rate extrapolation factors for malignant and non-malignant health endpoints after exposure to gamma and neutron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Van; Little, Mark P. [National Cancer Institute, Radiation Epidemiology Branch, Rockville, MD (United States)

    2017-11-15

    Murine experiments were conducted at the JANUS reactor in Argonne National Laboratory from 1970 to 1992 to study the effect of acute and protracted radiation dose from gamma rays and fission neutron whole body exposure. The present study reports the reanalysis of the JANUS data on 36,718 mice, of which 16,973 mice were irradiated with neutrons, 13,638 were irradiated with gamma rays, and 6107 were controls. Mice were mostly Mus musculus, but one experiment used Peromyscus leucopus. For both types of radiation exposure, a Cox proportional hazards model was used, using age as timescale, and stratifying on sex and experiment. The optimal model was one with linear and quadratic terms in cumulative lagged dose, with adjustments to both linear and quadratic dose terms for low-dose rate irradiation (<5 mGy/h) and with adjustments to the dose for age at exposure and sex. After gamma ray exposure there is significant non-linearity (generally with upward curvature) for all tumours, lymphoreticular, respiratory, connective tissue and gastrointestinal tumours, also for all non-tumour, other non-tumour, non-malignant pulmonary and non-malignant renal diseases (p < 0.001). Associated with this the low-dose extrapolation factor, measuring the overestimation in low-dose risk resulting from linear extrapolation is significantly elevated for lymphoreticular tumours 1.16 (95% CI 1.06, 1.31), elevated also for a number of non-malignant endpoints, specifically all non-tumour diseases, 1.63 (95% CI 1.43, 2.00), non-malignant pulmonary disease, 1.70 (95% CI 1.17, 2.76) and other non-tumour diseases, 1.47 (95% CI 1.29, 1.82). However, for a rather larger group of malignant endpoints the low-dose extrapolation factor is significantly less than 1 (implying downward curvature), with central estimates generally ranging from 0.2 to 0.8, in particular for tumours of the respiratory system, vasculature, ovary, kidney/urinary bladder and testis. For neutron exposure most endpoints, malignant and

  1. In vivo variation of micronuclei in BALB/c mice after low and high doses of gamma radiation

    International Nuclear Information System (INIS)

    Strain, D.; Allen, B.J.

    1996-01-01

    Full text: An adaptive response to ionising radiation exists if a low level or priming dose reduces the effect of a subsequent high or challenge dose. This has been demonstrated in vitro using the frequency of micronuclei formation as a measure of radiation-induced DNA damage. The objective of this project was to use the same approach with an animal model to investigate the existence of an in vivo adaptive response. The experimental design involved priming doses of 0.005 or 0.01 Gy and a challenge dose of 4 Gy administered 1, 2, 4, 8 or 16 hours after the priming dose. Ten mice at a time were housed in a perspex animal cage and irradiated using Co-60 gamma radiation. For every time point (1, 2, 4, 8 or 16 hours), there were four treatment groups of 5 mice for statistical analysis. The first group acted as a non-irradiated control (0 Gy). The second group of mice received only the priming dose (0.005 Gy), while the third group of mice received only the challenge dose (4 Gy). The fourth group of mice received both the priming and challenge doses 0.005 Gy + 4 Gy). The process was repeated for the second priming dose of 0.01 Gy. A total of 200 mice were used. The animals were sacrificed by cervical dislocation 24 hours after receiving the challenge dose. Both femora were removed and cleared of adhering muscle tissue. The bone marrow cells of five mice were collected and the nucleated cells removed using filtration through a mixed cellulose column incorporating a self-locking filter. The cell suspension was placed onto microscope slides using a cytocentrifuge, air-dried and then stained for the micronuclei. Then the slides were coded, and reticulocytes were scored for the presence or absence of micronuclei. Approximately 2500 cells were scored for each treatment point, and the number of micronuclei counted ranged from 3 to 125 in this sample size. While it appears that the adaptive response may be present in 2 of 9 groups of mice pre-exposed to 0.005 or 0.01 Gy, this

  2. Gamma radiation and chickens

    International Nuclear Information System (INIS)

    Toropilova, D.; Takac, L.; Toropila, M.; Tomko, M. M.

    2014-01-01

    In our work, we focused the effect of low doses of gamma radiation on metabolic parameters in chickens. In the first group of chickens we monitor changes of the concentration in glucose and cholesterol after whole body irradiation dose of chicken (3 Gy). In the second group of chickens we studied the combined effect of radiation and intraperitoneal application solution of zinc chloride to changes of the concentration in glucose and total cholesterol. In the tissues of organisms are found only in a very small amount of microelements however are of particular importance in a number of enzymatic catalytic and regulatory processes. Zinc is found in all cells of the body. However, it is the highest percentage of zinc contained in muscle and bone cells. Resorption takes place in the small intestine, especially in the duodenum. For both groups of chickens, we performed analyzes on the 3 rd , 7 th , 14 th , 21 st and 30 day. Results and an overview of the work can be helpful in the peaceful uses of nuclear energy and in preventing diseases from exposure to radiation, but also in the case of the consequences after nuclear accidents. (authors)

  3. Degradation of polylactic acid (Pla) at different doses of gamma radiation; Degradacion del acido polilactico (PLA) a diferentes dosis de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Castillo R, Y.

    2015-07-01

    The excessive use of polymers such as polyethylene (PET), polystyrene (Ps) and recently the polylactic acid (Pla) that take more than 20 years to degrade, have caused great pollution in the environment. In this study the effects of gamma radiation in the Pla to different doses were studied, in order to reduce the degradation time of this polymer. The changes in physico-chemical structure of Pla during radiation were studied by thermo-gravimetric/Mass analysis; differential scanning calorimetry; scanning electron microscopy; X-ray dispersive analysis; infrared spectroscopy; X-ray diffraction and mechanical tests of hardness, elasticity and deformation. With scanning electron microscopy, the morphology of the Pla surface unirradiated was observed, in which an apparently smooth surface was observed, after changes that had the Pla when irradiated also was observed, where the effects of radiation were observed in form of scratch, agglomeration and small fractures. By X-ray dispersive analysis was determined and verified the elemental chemical composition of the Pla; as expected the tests showed only carbon, oxygen and hydrogen. With thermo-gravimetric/Mass analysis the decomposition temperatures of Pla were determined, identifying that the degradation compounds are CO, CO{sub 2} and CH{sub 4}. With infrared spectrometry the major peaks of Pla were observed before and after being irradiated with increasing of radiation dose the intensity of the bands decreased. Also by X-ray diffraction was observed that the polymer is an amorphous material. The mechanical tests indicate that the values of each of the tests decrease significantly with increasing the radiation dose. (Author)

  4. Low dose UV and gamma radiation on storage rot and physicochemical changes in peaches

    International Nuclear Information System (INIS)

    Lu, J.Y.; Lukombo, S.M.; Stevens, C.; Khan, V.A.; Wilson, C.L.; Pusey, P.L.; Chaultz, E.

    1993-01-01

    Peach fruit were irradiated with 7.5 x 10(4) ergs/mm(2) of UV (254nm) or 0.1 kGy gamma rays or a combination of both, then stored at 16C for 21 days. The results showed that both UV and gamma rays reduced storage rot and delayed ripening. UV treated peaches had lower sugar concentration, total phenols, anthocyanins and lower weight loss than the gamma treated peaches. The combination of UV and gamma showed no advantage over the use of UV or gamma alone

  5. Calibration curve to establish the exposure dose at Co{sup 60} gamma radiation; Curva de calibracion para establecer dosis de exposicion a radiacion gamma de Co{sup 60}

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C; Brena V, M [Departamento de Biologia, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Mexico D.F. (Mexico)

    2000-07-01

    The biological dosimetry is an adequate method for the dose determination in cases of overexposure to ionizing radiation or doubt of the dose obtained by physical methods. It is based in the aberrations analysis produced in the chromosomes. The behavior of leisure in chromosomes is of dose-response type and it has been generated curves in distinct laboratories. Next is presented the curve for gamma radiation produced in the National Institute of Nuclear Research (ININ) laboratory. (Author)

  6. Environmental gamma dose rate monitoring along Mumbai-Pune route using environmental radiation monitor with navigational aid

    International Nuclear Information System (INIS)

    Padmanabhan, N.; Kale, M.S.; Raman, N.; Krishnamachari, G.; Harikumar, M.; Sharma, D.N.; Mehta, S.K.

    1997-01-01

    A continuous environmental radiation monitor with navigational aid (ERMNA) for mapping natural gamma radiation background on country wide scale by deployment in railway coaches, has been designed. The system makes use of Indian railway network which is one of the widest network of railways in the world covering nearly complete length and breadth of the country. The system uses an energy compensated (within ± 30%) GN detectors for measurement of environmental dose rate due to natural background, a global positioning system (GPS) for on-line acquisition of positional co-ordinates (longitude and latitude) and an 8085 based data acquisition and processing unit. This system is deployed in guard's cabin of a train. The dose rate data tagged with positional co-ordinates and collected by the system during train journey is down loaded into a Lap Top PC for storage, analysis and graphical representation. The system has been used for background monitoring between Mumbai and Pune. The dose rates recorded over a period of three months ranging from November 1996 to February 1997 along the route show no change in the values which vary from 4 μr/h to 6 μR/h along the route. It drops down to <3 μR/h within tunnels en route. (author)

  7. Ambient radiation dose to the population of the city of Sao Paulo-Brazil: indoor gamma distribution

    International Nuclear Information System (INIS)

    Otsubo, Sergio M.; Yoshimura, Elizabeth M.

    2001-01-01

    The objective of this work is to present results of indoor ambient dose equivalent rate (H * (10)) in the city of Sao Paulo. Studies show that people of industrialized cities spend indoor approximately 80% of their time, and that there are great variations of the rate of H * (10) all over the world. Values of environmental radiation are important base to epidemiological studies, or analyses of consequences and effects of radioactive or nuclear accidents and also to assist research on biological effects of low doses, a very controversial subject in the literature. There are no reports in the literature about environmental radiation in the city of Sao Paulo, showing the important of this study. Environmental radiation exists everywhere in the planet, so the human beings are exposed to it at any time or place, being indoor or outdoor. Three types of commercial indoor ambient with large flow of the population were analyzed: bank offices, shops in the neighborhood of the banks, and shopping centers. A gamma ray portable spectrometer was used, composed by a crystal of NaI (Tl). The mean value of the H * (10) rate obtained was 173,8(17) nSv/h. The results analyzed by commerce type and by the health divisions of the city are also presented. (author)

  8. Gamma radiation in dwellings

    International Nuclear Information System (INIS)

    Mjoenes, L.

    1981-08-01

    A nationwide investigation has been made into the gamma radiation in Swedish dwellings. The measurements were made with small detectors containing thermoluminescent dosimeters. The detectors were sent to the selected participants by mail. 1300 dwellings were included in the investigation. In each dwelling three measurements were made: one detector was placed in the kitchen, one in the living-room and one in the bedroom. The mean annual absorbed tissue dose in dwellings in Sweden was found to be 0.65 mGy (corresponding to an exposition rate of 12 μR/h) when the contribution from cosmic radiation had been subtracted. That represents an annual collective dose of about 4000 mansieverts to the population of Sweden. From a previous investigation we have calculate the mean value for the gamma radiation in Swedish dwellings for 1950 to be 0.4 mGy/a (8μR/h). The reason for the relatively large increase in the mean value is an increased use of building materials on stone, particularly of lightweight concrete based on alum shale, from 1940 to middle 1960s. The production of this type of lightweight concrete was discontinued in 1975 and the use of other stone-based building materials has decreased. The mean value of gamma radiation in Swedish dwellings is therefore expected to decrease slowly in the future if this tendency holds. Sweden has some 3.5 million dwellings. About 10 % of them have mean values of 1 mGy/a (19 μR/h) or more, 0.2 % have 3 mGy/a (57 μR/h) or more and a couple of hundred 5 mGy/a (95 μR/h or more. The mean value for detached houses was found to be 0.43 mGy/a (8 μR/h) and for dwellings in multi-family houses 0.80 mGy/a (15 μR/h). The investigation dwellings have also been classified according to the building materials, the year of construction and the degree of urbanization of the area. (author)

  9. Dose-effect relationships for fife shortening, tumorigenesis, and systemic injuries in mice irradiated with fission neutron or 60Co gamma radiation

    International Nuclear Information System (INIS)

    Ainsworth, E.J.; Fry, R.J.M.; Williamson, F.S.; Brennan, P.C.; Stearner, S.P.; Yang, V.V.; Crouse, D.A.; Rust, J.H.; Borak, T.B.

    1977-01-01

    The objective of this research is to provide additional data on life shortening, neoplastic and non-neoplastic diseases, and other systematic injuries necessary for the determination of dose-response relationships. The data are used to test existing predictive models and formulate new models which may assist with radiation risk assessment. Late somatic effects of fission neutrons from the JANUS reactor or from cobalt-60 gamma radiation are evaluated in young adult B6CF 1 mice that receive either a range of single doses or protracted doses at low dose rates; the protracted irradiation is administered over a 6-month period. After single doses of gamma radiation the relationship between radiation dose and percent life shortening appears linear whereas after single doses of fission spectrum neutrons a non-linear dose response is observed. These results suggest that estimates of radiation risk for fission spectrum neutrons should take into account the following: the curvilinearity of the neutron dose-response curve for life shortening, and the increased life shortening produced by neutron dose fractionation

  10. Measurement of radiocesium concentration in trees using cumulative gamma radiation dose rate detection systems - A simple presumption for radiocesium concentration in living woods using glass-badge based gamma radiation dose rate detection system

    Energy Technology Data Exchange (ETDEWEB)

    Yoshihara, T.; Hashida, S.N. [Plant Molecular Biology, Laboratory of Environmental Science, Central Research Institute of Electric Power Industry (CRIEPI), 1646 Abiko, Chiba 270-1194 (Japan); Kawachi, N.; Suzui, N.; Yin, Y.G.; Fujimaki, S. [Radiotracer Imaging Gr., Quantum Beam Science Center, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Nagao, Y.; Yamaguchi, M. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2014-07-01

    Radiocesium from the severe accident at the Fukushima Dai-ichi Nuclear Power Plant on 11 March 2011 contaminates large areas. After this, a doubt for forest products, especially of mushroom, is indelible at the areas. Pruned woody parts and litters are containing a considerable amount of radiocesium, and generates a problem at incineration and composting. These mean that more attentive survey for each subject is expected; however, the present survey system is highly laborious/expensive and/or non-effective for this purpose. On the other hand, we can see a glass-badge based gamma radiation dose rate detection system. This system always utilized to detect a personal cumulative radiation dose, and thus, it is not suitable to separate a radiation from a specific object. However, if we can separate a radiation from a specific object and relate it with the own radiocesium concentration, it would enable us to presume the specific concentration with just an easy monitoring but without a destruction of the target nature and a complicated process including sampling, pre-treatment, and detection. Here, we present the concept of the measurement and results of the trials. First, we set glass-badges (type FS, Chiyoda Technol Corp., Japan) on a part of bough (approximately 10 cm in diameter) of Japanese flowering cherry trees (Prunus x yedoensis cv. Somei-Yoshino) with four different settings: A, a direct setting without any shield; B, a setting with an aluminum shield between bough and the glass-badge; C, a setting with a lead shield between bough and the glass-badge; D, a setting with a lead shield covering the glass-badge to shut the radiation from the surrounding but from bough. The deduction between the amount of each setting should separate a specific radiation of the bough from unlimited radiation from the surrounding. Even if the hourly dose rate is not enough to count the difference, a moderate cumulative dose would clear the difference. In fact, results demonstrated a

  11. Evaluation of different doses of gamma radiation on physicochemical characteristics of peach Prunus persica (cv. Chimarrita) minimally processed

    International Nuclear Information System (INIS)

    Oliveira, Ana Claudia S.; Silva, Lucia C.A.S.; Perecin, Thalita Neme; Arthur, Valter; Harder, Marcia N.C.; Mansi, Debora N.; Canniatti-Brazaca, Solange G.

    2009-01-01

    The objective was to evaluate the effect of different doses of gamma radiation on the physico-chemical characteristics of peach Prunus persica (cv. Chimarrita) minimally processed, to increase the useful life of the fruit. The peaches were purchased at Ceasa of Campinas/SP and taken to the Laboratory of Radiobiology and Environment of CENA/USP (Piracicaba/SP), which were washed in tap water, peeled and cut into four pieces. The pieces of peach were dipped in sodium hypochlorite solution of 15 mL/L for 4 minutes and dry in a plastic support. Then it were placed in plastic containers (polypropylene). Subsequently, they were irradiated in a Cobalt-60 source, type Gammacell-220 (dose rate of 0,543 kGy/hour) with doses of: 0 (control), 1.0 and 2.0 kGy and stored at a temperature of 8 deg C. The experimental was developed entirely at random with 3 replicates for each treatment. For the statistic analysis was using the Tuckey test at 5% level of probability. Subsequently, analysis was carried out: color factors (l, a, b), pH, soluble solids (deg Brix), acidity and vitamin C. The tests were performed at 1, 3 and 6 days after irradiation. According to the results concluded that the analysis of color and acidity there was no significant difference between treatments, however, for the soluble solids (deg Brix), vitamin C and texture significant difference showing a decrease proportional to increasing doses of radiation and storage time. But the pH increased in relation to dose and during the analysis. (author)

  12. Determination of gamma radiation lethal dose (LD{sub 50}) and resveratrol cytotoxicity level in tumor cells line

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Cruz, Aurea S. [Instituto Adolfo Lutz (IAL-SP) Secao de Culturas Celulares, SP (Brazil)

    2011-07-01

    Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD{sub 50}) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC{sub 50%} in NCI-H292 cells was 192{mu}M and in RD cells was 128{mu}M; and RD cells gamma radiation LD{sub 50} was 435Gy. (author)

  13. Dose-Related Effects of Acetylsalicylic acid (ASA) on Gamma Radiation-Induced Teratogenicity in Pregnant Albino Rats

    International Nuclear Information System (INIS)

    Ibrahim, M.F.

    2013-01-01

    Reviews of acetylsalicylic acid (ASA), a widely used nonsteroidal anti- inflammatory drug, has consistently suggested a possible association between prenatal ASA ingestion and adverse effects in the pregnant mothers and their developing fetuses. The objective of the current study was to comprehensively define the effect of relatively low and high doses of ASA (25 mg/kg body wt. and 200 mg/kg body wt. respectively) on gestating rats and their possible impact on the irradiated ones. Therefore 36 pregnant rats were randomly divided into 6 equal groups. Three rat groups were daily orally gavaged from the 7th to the 18th gestational days with: distilled water (Group 1), 25 mg/kg body wt. ASA (Group 2) and 200 mg/kg body wt. ASA (Group 3). The other three groups similarly received the same previous treatments besides 2 Gy whole body gamma irradiation of each, to serve as: Group 4 (distilled water + irradiation), Group 5 (25 mg/kg body wt. ASA + irradiation) and Group 6 (200 mg/kg body wt. ASA + irradiation). All rat groups were sacrificed on the 20th day of pregnancy and the uterine contents were examined. The lower ASA dose (25 mg/kg body wt.) treated group (Group 2) displayed healthy mothers and fetuses whereas that of the higher dose (200 mg/kg body wt.) (Group 3) despite not showing significant maternal or fetal mortalities, yet the intrauterine contents presented fetal developmental disorders including stunted growth and resorption together with some head and limb anomalies including plagiocephaly, marked acampsia and acrocontracture. Meanwhile, results have unexpectedly shown a radioprotective role of the lower ASA dose (25 mg/kg. body wt.) (Group 5) to pregnant rats and their fetuses as inspected by its efficacy in retrieving the radiation induced maternal weight loss together with its noticeable ameliorating effects on the intrauterine lethality of the affected fetuses and their externally detected abnormalities in addition toits effectiveness in retaining some

  14. Adaptive Response to ionizing Radiation Induced by Low Doses of Gamma Rays in Human Lymphoblastoid Cell Lines

    International Nuclear Information System (INIS)

    Seong, Jin Sil; Suh, Chang Ok; Kim, Gwi Eon

    1994-01-01

    When cells are exposed to low doses of a mutagenic or clastogenic agents, they often become less sensitive to the effects of a higher does administered subsequently. Such adaptive responses were first described in Escherichia coli and mammalian cells to low doses of an alkylating agent. Since most of the studies have been carried out with human lymphocytes, it is urgently necessary to study this effect in different cellular systems. Its relation with inherent cellular radiosensitivity and underlying mechanism also remain to be answered. In this study, adaptive response by 1 cGy of gamma rays was investigated in three human lymphoblastoid cell lines which were derived from ataxia telangiectasia homozygote, ataxia telangiectasia heterozygote, and normal individual. Experiments were carried out by delivering 1 cGy followed by 50 cGy of gamma radiation and chromatid breaks were scored as an endpoint. The results indicate that prior exposure to 1 cGy of gamma rays reduces the number of chromatid breaks induced by subsequent higher does (50 cGy). The expression of this adaptive response was similar among three cell lines despite of their different radiosensitivity. When 3-aminobenzamide, an inhibitor of poly (ADP-ribose) polymerase, was added after 50 cGy, adaptive responses were abolished in all the tested cell lines. Therefore it is suggested that the adaptive response can be observed in human lymphoblastoid cell lines. Which was first documented through this study. The expression of adaptive response was similar among the cell lines regardless of their radiosensitivity. The elimination of the adaptive response by 3-aminobenzamide is consistent with the proposal that this adaptive response is the result of the induction of a certain chromosomal repair mechanism

  15. The effect of substerilizing doses of gamma radiation on the pupae of the carob moth Ectomyelois ceratoniae (Lepidoptera: Pyralidae)

    International Nuclear Information System (INIS)

    Dhouibi, M.H.; Abderahmane, C.T.

    2002-01-01

    We investigated various effects of gamma radiation on the carob moth, Ectomyelois ceratoniae, treated with 200-600 Gy at different pupal ages. Irradiation resulted in a decrease of adult emergence. This effect was both dose and age dependent. At 500 and 600 Gy, no pupae developed into normal adults when treated at the age of 4-5 days. Only 6% normal adults emerged when the pupae were treated at the age of 6-7 days with 500 Gy. When 8-9 d old pupae were irradiated with 500 and 600 Gy, 30% and 10% normal adults emerged, respectively. Other emerged moths exhibited various malformations, mostly wing deformities. When pupae were treated with 400 or 500 Gy, fecundity and fertility of both untreated females mated with irradiated males or irradiated females mated with untreated males were drastically reduced. When 9-10 d old pupae were irradiated with 200, 250 and 300 Gy, adult morphology, fecundity, fertility and egg hatch were slightly affected. Mating behaviour of irradiated males also was affected. Competitiveness of males irradiated with sub-sterilizing doses varied depending on irradiation dose and number of insects present in the mating cages. A significant reduction of competitiveness was observed in males treated with ≤300Gy. (author)

  16. The effect of substerilizing doses of gamma radiation on the pupae of the carob moth Ectomyelois ceratoniae (Lepidoptera: Pyralidae)

    Energy Technology Data Exchange (ETDEWEB)

    Dhouibi, M H; Abderahmane, C T [Laboratoire d' Entomologie de l' Institut National Agronomique de Tunisie, Tunis Mahrajene (Tunisia)

    2002-04-01

    We investigated various effects of gamma radiation on the carob moth, Ectomyelois ceratoniae, treated with 200-600 Gy at different pupal ages. Irradiation resulted in a decrease of adult emergence. This effect was both dose and age dependent. At 500 and 600 Gy, no pupae developed into normal adults when treated at the age of 4-5 days. Only 6% normal adults emerged when the pupae were treated at the age of 6-7 days with 500 Gy. When 8-9 d old pupae were irradiated with 500 and 600 Gy, 30% and 10% normal adults emerged, respectively. Other emerged moths exhibited various malformations, mostly wing deformities. When pupae were treated with 400 or 500 Gy, fecundity and fertility of both untreated females mated with irradiated males or irradiated females mated with untreated males were drastically reduced. When 9-10 d old pupae were irradiated with 200, 250 and 300 Gy, adult morphology, fecundity, fertility and egg hatch were slightly affected. Mating behaviour of irradiated males also was affected. Competitiveness of males irradiated with sub-sterilizing doses varied depending on irradiation dose and number of insects present in the mating cages. A significant reduction of competitiveness was observed in males treated with {<=}300Gy. (author)

  17. Evaluation of different doses of gamma radiation on conservation of the physicochemical and sensorial characteristics of previously fried potatoes

    International Nuclear Information System (INIS)

    Amaral, Frederico Scarin do; Sanches, Maria Angelica Santos Fernandes; Arthur, Valter

    2007-01-01

    The goal of this work was to study the effect of different doses of gamma radiation on the physicochemical and sensorial characteristics of previously fried potatoes, conserved under temperature of refrigeration from 7 to 10 deg C. The irradiation process aims to discharge the refrigeration that increases the cost of the product and the useful life and decreases the microbial load. The previously fried potatoes were in the commerce of Piracicaba City and led to CENA - a laboratory of Food Irradiation. The potatoes were defrosted and stored in plastic packages and irradiated. They were irradiated in a Cobalto-60 source type Gammacell-220 (dose rate of 698 Gy/hour), with doses of 2,0 kGy, 4,0 kGy and 6,0 kGy. The loss of fresh weight was analyzed as well as smell and color (factors L, a, b), after 1, 4 and 6 days of radiation. The experimental delineation used was entirely at random with six repetitions. The irradiated previously fried potatoes presented more significant variations in relation to those not irradiated in relation to their color and smell. The potatoes were darkened and there was alteration of smell (rancidity) more intense in the samples with doses of irradiation of 4,0 and 6,0 kGy. The smell alteration caused by the irradiation of 4,0 and 6,0 kGy. The smell alteration caused by the irradiation happens because of the state of rancidity of the oil used in the previous-fried process. In the sample of 2,0 kGy there was no alteration of color and smell. The colorimetric rates: L, a, b, did not present statistically - coherent results. However it was visually noted in the irradiated samples with doses of 4,0 and 6,0 kGy the loss of the characteristic coloration of the previously fried potato, predominating an opaque color (gray) because of the degradation of pigments (betacarotenoids, etc). It is also an consequence of the irradiation. By analyzing the results it was concluded that the irradiated sample with doses of 2,0 kGy was the sample that maintained

  18. Evaluation of different doses of gamma radiation on conservation of the physicochemical and sensorial characteristics of previously fried potatoes

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Frederico Scarin do; Sanches, Maria Angelica Santos Fernandes [Fundacao Educacional de Fernandopolis FEF-SP, Fernandopolis, SP (Brazil)]. E-mails: maengal@yahoo.com.br; frescarin@yahoo.com.br; Arthur, Valter [Centro de Energia Nuclear na Agricultura CENA, Piracicaba, SP (Brazil). Lab. de Irradiacao de Alimentos e Radioentomologia]. E-mail: arthur@cena.usp.br

    2007-07-01

    The goal of this work was to study the effect of different doses of gamma radiation on the physicochemical and sensorial characteristics of previously fried potatoes, conserved under temperature of refrigeration from 7 to 10 deg C. The irradiation process aims to discharge the refrigeration that increases the cost of the product and the useful life and decreases the microbial load. The previously fried potatoes were in the commerce of Piracicaba City and led to CENA - a laboratory of Food Irradiation. The potatoes were defrosted and stored in plastic packages and irradiated. They were irradiated in a Cobalto-60 source type Gammacell-220 (dose rate of 698 Gy/hour), with doses of 2,0 kGy, 4,0 kGy and 6,0 kGy. The loss of fresh weight was analyzed as well as smell and color (factors L, a, b), after 1, 4 and 6 days of radiation. The experimental delineation used was entirely at random with six repetitions. The irradiated previously fried potatoes presented more significant variations in relation to those not irradiated in relation to their color and smell. The potatoes were darkened and there was alteration of smell (rancidity) more intense in the samples with doses of irradiation of 4,0 and 6,0 kGy. The smell alteration caused by the irradiation of 4,0 and 6,0 kGy. The smell alteration caused by the irradiation happens because of the state of rancidity of the oil used in the previous-fried process. In the sample of 2,0 kGy there was no alteration of color and smell. The colorimetric rates: L, a, b, did not present statistically - coherent results. However it was visually noted in the irradiated samples with doses of 4,0 and 6,0 kGy the loss of the characteristic coloration of the previously fried potato, predominating an opaque color (gray) because of the degradation of pigments (betacarotenoids, etc). It is also an consequence of the irradiation. By analyzing the results it was concluded that the irradiated sample with doses of 2,0 kGy was the sample that maintained

  19. Gamma radiation-induced conditioned taste aversions in rats: A comparison of the protective effects of area postrema lesions with differing doses of radiation

    International Nuclear Information System (INIS)

    Ossenkopp, K.P.; Giugno, L.

    1989-01-01

    Lesions which destroy the area postrema (AP) and damage the adjacent nucleus of the solitary tract (NTS) attenuate or abolish conditioned taste aversions (CTA) induced by a variety of pharmacological agents as well as exposure to radiation. In the present experiment, 4 groups of male rats received lesions of AP and 4 groups were given sham lesions. One sham-lesioned and one AP-lesioned group were given a single pairing of 1-hr access to a novel 0.10% sodium saccharin solution followed immediately with exposure to 0, 100, 200, or 400 rad of gamma radiation, respectively. Four days later all groups were given daily two-bottle preference tests (saccharin vs. water) on 4 consecutive days. The sham-lesioned groups exposed to the radiation (100, 200, or 400 rad) developed profound aversions to the saccharin on all test days (p less than 0.001). In contrast, all of the AP-lesioned groups as well as the sham-irradiated (0 rad) sham-lesioned group exhibited strong, comparable (p greater than 0.30) preferences for saccharin. Thus, lesion of AP abolished the radiation-induced CTA at all dose levels of radiation. These results raise the possibility of pharmacological intervention at the level of AP to prevent radiation-induced CTA in cancer patients undergoing radiation therapy

  20. Environmental Gamma Radiation Measurements in Baskil District

    International Nuclear Information System (INIS)

    Canbazoglu, C.

    2008-01-01

    In this study, we have determined environmental gamma radiation dose rate in Baskil district which has very high granite content in its geographical structure. Gamma radiation dose rate measurements were achieved by portable radiation monitoring equipment based on the energy range between 40 keV and 1.3 MeV. The measurements were performed on asphalt and soil surface level and also one meter above the ground surface. The gamma dose rate was also performed inside and outside of buildings over the district. The dose rates were found to be between 8.46μR/h and 34.66 μR/h. Indoor and outdoor effective dose rate of the gamma radiation exposure has been calculated to be 523μSv/y and 196μSv/y, respectively

  1. Use of TL dosemeters for measuring doses of external gamma radiation in the vicinity of the Dukovany NPP

    International Nuclear Information System (INIS)

    Ohera, M.; Fiala, E.; Valasek, J.

    1992-01-01

    The results of measurement of the photon dose equivalent from external gamma radiation in the surroundings of the Dukovany nuclear power plant are given for 20 sites in southern Moravia over the 1984-1990 period, i.e., one year before starting up the plant and 6 years of its operation. CaSO 4 :Dy TL dosemeters were used, applying filtration with 0.5 mm Pb and 0.2 mm Pb + 0.6 mm Sn. Since 1989, the towns along the borders with Austria (Znojmo, Vranov, Mikulov) have been included, along with the Brno, Trebic, Zakrany, Ivancice and Jaromerice sites, into the national monitoring TL dosimetric network. The elevated doses at some sites come from the bedrock and are not caused by the operation of the plant. The effect of the Chernobyl accident on the dosemeter response is also evaluated. Comparison of the data prior to the Dukovany plant start-up (1984) and during the operation (1985-1990) give evidence that the operation of the power plant did not bring about any increase in the values monitored. (Z.S.). 3 tabs., 8 figs., 9 refs

  2. Homologous tracheal transplantation with grafts previously exposed to high doses of gamma radiation in dogs without immunosuppressive agents

    International Nuclear Information System (INIS)

    Yokomise, Hiroyasu; Inui, Kenji; Kure, Toshio; Wada, Hiromi; Itomi, Shigeki

    1993-01-01

    The study was designed to determine whether previous high doses irradiation of gamma radiation would contribute to tracheal transplantation with no use of immunosuppressive agents. Twenty mongrel dogs were used as experimental animals. Five rings of thoracic tracheas, which were extracted from recipients, were exposed to 20000, 50000, or 100000 cGy in each 5 dogs. Five other non-irradiated dogs served as controls. Irradiated tracheal grafts were transplanted and covered with pedicled omentum. After transplantation, no immunosuppressive agents were given to dogs. All dogs in the control group died of tracheal stenosis due to graft-host rejection within one month. All but one long-term survivor died of tracheal stenosis, as well, in both the 20000 cGy and 50000 cGy groups. In the 100000 cGy group, grafts became viable in 4 dogs, and three of these survived one year or more. In conclusion, previous irradiation with high doses of 100000 cGy allowed homologous tracheal transplantation even when no immunosuppressive agents are given. (N.K.)

  3. Development of air equivalent gamma dose monitor

    International Nuclear Information System (INIS)

    Alex, Mary; Bhattacharya, Sadhana; Karpagam, R.; Prasad, D.N.; Jakati, R.K.; Mukhopadhyay, P.K.; Patil, R.K.

    2010-01-01

    The paper describes design and development of air equivalent gamma absorbed dose monitor. The monitor has gamma sensitivity of 84 pA/R/h for 60 Co source. The characterization of the monitor has been done to get energy dependence on gamma sensitivity and response to gamma radiation field from 1 R/hr to 5000 R/hr. The gamma sensitivity in the energy range of 0.06 to 1.25MeV relative to 137 Cs nuclide was within 2.5%. The linearity of the monitor response as a function of gamma field from 10 R/h to 3.8 kR/h was within 6%. The monitor has been designed for its application in harsh environment. It has been successfully qualified to meet environmental requirements of shock. (author)

  4. Phosphorylation of histone H2AX as an indicator of received dose of gamma radiation after whole-body irradiation of rats

    Directory of Open Access Journals (Sweden)

    Radim Havelek

    2011-01-01

    Full Text Available The aim of our study was to determine whether phosphorylation of histone H2AX can be used as an indicator of received dose of gamma radiation after whole-body irradiation of rats. Wistar rats were irradiated by 1-10 Gy of gamma radiation by 60Co source. Value LD50/60 was 7.37 (4.68-8.05 Gy. Histone H2AX is phosphorylated by ATM kinase on serine 139 (γH2AX quickly after the irradiation. It forms microscopically visible foci in the site of double strand breaks of DNA. Flow-cytometric method was used for quantitative detection. This study is the first one that evaluated dose-dependency of H2AX phosphorylation in peripheral lymphocytes of rats irradiated by whole-body dose 1-10 Gy. Our data show a dose-dependent increase in γH2AX in rat peripheral blood lymphocytes 1 h after whole-body irradiation by the dose of 1-10 Gy. We proved that phosphorylation of histone H2AX is a prompt and reliable indicator of the received radiation dose suitable for rapid measurement before the number of lymphocytes in peripheral blood starts to decrease. It can be used already 1 h after the irradiation for an estimation of the received dose of radiation. Blood samples can be stored in 4 °C for 23 h without significantly affecting the result.

  5. Effects of gamma radiation in tomato seeds

    Energy Technology Data Exchange (ETDEWEB)

    Wiendl, Toni A.; Wiendl, Fritz W.; Franco, Suely S.H.; Franco, Jose G.; Althur, Valter, E-mail: tawiendl@hotmail.com, E-mail: gilmita@uol.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Arthur, Paula B., E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

    2013-07-01

    Tomato dry seeds of the hybrid 'Gladiador' F1 were exposed to low doses of gamma radiation from Co-60 source at 0,509 kGy tax rate in order to study stimulation effects of radiation on germination and plant growth. Eight treatments radiation doses were applied as follows: 0 (control); 2,5; 5,0; 7,5; 10,0; 12,5; 15,0; 20,0 Gy. Seed germination as well as green fruits number, harvested fruit number, fruit weight and total production were assessed to identify occurrence of stimulation. Tomato seeds and plants were handled as for usual tomato production in Brazil. Low doses of gamma radiation treatment in the seeds stimulate germination and substantially increase fruit number and total production up to 86% at 10 Gy dose. There are evidences that the use of low doses of gamma radiation can stimulate germination and plant production thus, showing hormetic effects. (author)

  6. Effects of gamma radiation in tomato seeds

    International Nuclear Information System (INIS)

    Wiendl, Toni A.; Wiendl, Fritz W.; Franco, Suely S.H.; Franco, Jose G.; Althur, Valter; Arthur, Paula B.

    2013-01-01

    Tomato dry seeds of the hybrid 'Gladiador' F1 were exposed to low doses of gamma radiation from Co-60 source at 0,509 kGy tax rate in order to study stimulation effects of radiation on germination and plant growth. Eight treatments radiation doses were applied as follows: 0 (control); 2,5; 5,0; 7,5; 10,0; 12,5; 15,0; 20,0 Gy. Seed germination as well as green fruits number, harvested fruit number, fruit weight and total production were assessed to identify occurrence of stimulation. Tomato seeds and plants were handled as for usual tomato production in Brazil. Low doses of gamma radiation treatment in the seeds stimulate germination and substantially increase fruit number and total production up to 86% at 10 Gy dose. There are evidences that the use of low doses of gamma radiation can stimulate germination and plant production thus, showing hormetic effects. (author)

  7. Cytogenetic effect of low dose gamma-radiation in Hordeum vulgare seedlings: non-linear dose-effect relationship.

    Science.gov (United States)

    Geras'kin, Stanislav A; Oudalova, Alla A; Kim, Jin Kyu; Dikarev, Vladimir G; Dikareva, Nina S

    2007-03-01

    The induction of chromosome aberrations in Hordeum vulgare germinated seeds was studied after ionizing irradiation with doses in the range of 10-1,000 mGy. The relationship between the frequency of aberrant cells and the absorbed dose was found to be nonlinear. A dose-independent plateau in the dose range from about 50 to 500 mGy was observed, where the level of cytogenetic damage was significantly different from the spontaneous level. The comparison of the goodness of the experimental data fitting with mathematical models of different complexity, using the most common quantitative criteria, demonstrated the advantage of a piecewise linear model over linear and polynomial models in approximating the frequency of cytogenetical disturbances. The results of the study support the hypothesis of indirect mechanisms of mutagenesis induced by low doses. Fundamental and applied implications of these findings are discussed.

  8. Effect of Low Dose Gamma Radiation Upon Phosphatase Activity in Blood Plasma of Chicken Hatched from Eggs Irradiated on the Seventh Day of Incubation

    International Nuclear Information System (INIS)

    Kraljevic, P.; Vilic, M.; Miljanic, S.; Simpraga, M.

    2008-01-01

    In our earlier studies chickens hatched from eggs irradiated with 0.15 Gy gamma rays before incubation showed a significantly higher growth than controls during the fattening period (1-42 days). The activity of aspartate-aminotransferase (AST), alanine-aminotransferase (ALT), acid phosphatase (ACP) and plasma glucose in the same chickens were also significantly higher. These results suggested that low-dose gamma-radiation stimulated certain metabolic processes in chickens hatched from eggs irradiated before incubation. Investigating the effect of low dose gamma radiation upon transferases activity in blood plasma of chickens hatched from eggs irradiated on the 7th day of incubation, i.e. in the time when organogenesis is completely finished, we found that on day 10, AST and ALT activity was significantly higher in the blood plasma of those chickens, whereas it significantly dropped for both enzymes on day 20. This time the goal of study was to determine the effect of low-dose gamma radiation on ACP and alkaline phosphatase (ALP) activity in the blood plasma of chickens hatched from eggs irradiated on the 7th day of incubation. The eggs of heavy breeding chickens (Avian, line 34) were exposed to 0.15 Gy of gamma radiation (60Co) on the seventh day of incubation. The control group included chickens hatched from non-irradiated eggs. All other conditions were the same for both groups. After hatching, blood samples were taken from the wing vein on days 1, 3, 5, 7, 10, 20, 32 and 42. The activity of both enzymes was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. ACP activity was significantly lower in the blood plasma of chickens hatched from irradiated eggs on day 3 (P<0,01), 5 (P<0,05) and 10 (P<0,05). Throughout the experimental period ALP activity did not statistically significantly change. Our results indicate that exposure of eggs to low-dose gamma radiation on the seventh day of incubation reduces ACP activity in the blood plasma

  9. Effective gamma radiation dose for rice genetic improvement by means of mutation radioinduction in Cuba

    International Nuclear Information System (INIS)

    Perez Talavera, S.; Labrada Remon, A.; Gonzalez, L.M.

    1993-01-01

    Determination of the useful radiation dosages for its employment in rice breeding in Cuban conditions was made; for this the radio sensibility of three commercial rice varieties was investigated using plant height in laboratory condition as criterion

  10. Calculating radiation exposure and dose

    International Nuclear Information System (INIS)

    Hondros, J.

    1987-01-01

    This paper discusses the methods and procedures used to calculate the radiation exposures and radiation doses to designated employees of the Olympic Dam Project. Each of the three major exposure pathways are examined. These are: gamma irradiation, radon daughter inhalation and radioactive dust inhalation. A further section presents ICRP methodology for combining individual pathway exposures to give a total dose figure. Computer programs used for calculations and data storage are also presented briefly

  11. Synthesis of Polyvinyl Pirrolidone (PVC /Κ-Carrageenan Hydrogel Prepared by Gamma Radiation Processing As a Function of Dose and PVP Concentration

    Directory of Open Access Journals (Sweden)

    Erizal Erizal

    2013-05-01

    Full Text Available The aim of this research is to prepare a biomaterial to be used in health care. A series of hydrogels based on polyvinyl pyrrolidone (PVP/κ-Carrageenan (KC has been prepared by radiation technique. PVP (5-15% were mixed with ΚC (2% and irradiated by gamma rays at the doses from 25 kGy to 35 kGy (dose rate 7 kGy/h at room temperature. The chemical change of hydrogels was characterized using Fourier Transform infra Red (FTIR. Gel fraction, water absorption and water evaporation were determined gravimetrically. Tensile strength and elongation at break was measured using Instron meter. It was found that with the increase irradiation dose and PVP concentration, the gel fraction and tensile strength of hydrogels increase. In contrast the elongation at break and water absorption of hydrogels decrease. The hydrogel of PVP/KC hydrogel produced by gamma radiation can be considered for wound dressings.

  12. Study on indoor radon concentration and gamma radiation dose rate in different rooms in some dwellings around Bharath Gold Mines Limited, Karnataka State, India

    International Nuclear Information System (INIS)

    Umesha Reddy, K.; Jayasheelan, A.; Sannappa, J.

    2012-01-01

    Indoor radon contributes significantly to the total radiation exposure caused to human beings. The indoor concentration of radon in different rooms in the same type of dwellings around Bharath Gold Mines Limited (BGML), Karnataka State (12°57' min N and 78°16' min E) were measured by using LR-115 (type-Il) Solid State Nuclear Track Detectors (SSNTDs). The maximum indoor radon concentration is observed in the bathroom and minimum in the hall. The maximum average indoor radon concentration is observed in the Champion and minimum in the BEML nagar. The indoor gamma radiation dose rate is also measured in these locations using scintillometer. The geology of this part forms predominantly Hornblende Schist, Granite gneiss, Champion gneiss, Quartzite etc. The indoor radon concentration shows good correlation with the indoor gamma radiation dose. (author)

  13. On the honeybee resistance to gamma radiation

    International Nuclear Information System (INIS)

    Courtois, G.; Lecomte, J.

    1960-01-01

    The honeybee, when irradiated by gamma radiations from a cobalt-60 source can stand a 18000 r dose without any apparent harm. Noticeable harm is observed for 90000 r. while immediate death of 100% of the individuals is obtained with a 200000 r dose. The physiological condition of the honeybee plays an important role in its resistance to gamma radiation. Reprint of a paper published in Annales de l'abeille, IV, 1959, p. 285-290 [fr

  14. Differential stimulation of antioxidant defense in various organs of mice after whole body exposure to low-dose gamma radiation

    International Nuclear Information System (INIS)

    Pathak, C.M.; Avti, P.K.; Khanduja, K.L.; Sharma, S.C.

    2007-01-01

    It has been generally considered that any dose of ionizing radiation is detrimental to the living organisms, however low the radiation dose may be. The much relied upon 'Linear-No-Threshold' (LNT) hypothesis dose not have any convincing experimental evidence regarding the damaging effects at very low-doses and low-dose rates. Generally, the deleterious biological effects have been inferred theoretically by extrapolating the known effects of high radiation dose to low-dose range. Recently, it has been reported that the living organisms do not respond to ionizing radiations in a linear manner in the low-dose range 0.01-0.50 Gy and rather restore the homeostasis both in-vivo and in-vitro by normal physiological mechanisms such as, cellular and DNA repair processes, immune reactions, antioxidant defense, adaptive responses, activation of immune functions; stimulation of growth etc. In this study, we have attempted to find: (i) the critical radiation dose range and the post irradiation period during which the antioxidant defense systems in the lungs, liver and kidneys remain stimulated; and (ii) to evaluate the degree to which these defense mechanisms remain stimulated in these organs after whole body exposure of the animal to low-dose radiation

  15. In vivo measurement by thermoluminescence of the gamma ray radiation dose to the uterus delivered during 131I therapy of Basedow's disease

    International Nuclear Information System (INIS)

    Philippon, B.; Briere, J.

    1977-01-01

    131 I is often the therapy of choice for BASEDOW's disease. The determination of radiation dose to the gonads from a therapeutic dose of 131 I is therefore of importance and the accuracy of radiation dose calculation is uncertain because of the numerous biological variables involved. The dose to the uterus was directly measured in 20 volonteers with Basedow's disease using a thermoluminescent dosimeter of lithium fluoride and calcium dysprosium sulfate, attached to a copper intrauterine contraceptive device. The dosimeters were inserted at the time of administration of 131 I and were retreived one month later. By this method, the dose to the uterus from gamma rays only was measured and a gamma ray dose equal to the dose to the uterus, was assumed to the ovaries. In vivo experimental results were compared with the values calculated using the specific absorbed fractions (PHI (r 2 - r 1 ) determined by SNYDER. In the calculations, the morphology of the patient, in particular the distance from thyroid to uterus was taken into account. The in vivo measurements have also been compared with direct in vivo measurements using phantoms. In vivo measurements indicate that the average dose to the uterus and ovaries is of the order of 1 rad per 10 mCi concentrated in the thyroid gland. These figures are below the generally accepted maximum admissible dose to the gonads of 10 rems [fr

  16. Development of tumours in dogs exposed to low doses of gamma radiation for a long time

    International Nuclear Information System (INIS)

    Yakovleva, V.I.

    1974-01-01

    150 animals were exposed to chronic (doses 21, 63 and 125 rad/year, with dose rates of 0.06, 0.17 and 0.34 rad/day, respectively) or combined γ-irradiation (chronic irradiation at 63 rad/year and acute irradiation at 58 and 126 rad/year) for a total period of 6 years. Post-mortem examination of 74 irradiated a7 animals revealed malignant neoplasms in 5 (flat-cell pulmonary carcinoma, hepatocellular liver carcinoma, skin basalioma, osteogenic costal sarcoma, and eye melanoma) and bening neoplasms also in 5 (3 leidigomas, parenchymatous thyroid struma and angiofibroma of hypodermic tissue). Of the 19 dogs in the control group, 2 had mammary tumours (cystadenoma and adenofibroma that changed to adenocarcinoma). Most of the neoplasms were seen in animals exposed to chronic irradiation with the highest dose rates as well as in those which received the highest total doses used in chronic irradiation. Acute effects were noted twice as often as chronic ones

  17. Wholesomeness studies with a full diet of irradiated dates, using the insect ephestia Cautella: 1. Disinfestation doses of gamma radiation

    International Nuclear Information System (INIS)

    Al-Hakkak, Z.S.; Ali, S.R.; Ahmed, M.S.H.; Al-Maliky, S.K.

    1983-01-01

    The study deals with the effect of feeding irradiated dates as a whole diet on some biological parameters of the fig moth ephestia cautella. Statistical analyses of the results indicated that the differences in the undermentioned parameters were insignificant when measured and compared with insects reared wholly either on irradiated or on unirradiated dry dates fruits. 1. Average numbers of larvae and pupae produced out of 400 seeded eggs after 30 days of incubation. 2. Average percentage of adult survival and their sex-ratio. 3. Mating frequency (average number of spermatophores per female) of the survived adults. 4. Average number of eggs laid per female. 5. Average percentage of eggs hatchability. 6. Mating frequency, average number of eggs per female and average percentage of egg hatchability of F1 progeny adults produced from insect parents reared on 100% diet of irradiated as well as on unirradiated dates. Therefore it could be concluded that disinfestation of date fruits by such a range of doses (50-100 krad) of gamma radiation might not have any adverse effect on the fig moth

  18. Measurements of integrated components' parameters versus irradiation doses gamma radiation (60Co) dosimetry-methodology-tests

    International Nuclear Information System (INIS)

    Fuan, J.

    1991-01-01

    This paper describes the methodology used for the irradiation of the integrated components and the measurements of their parameters, using Quality Insurance of dosimetry: - Measurement of the integrated dose using the competences of the Laboratoire Central des Industries Electriques (LCIE): - Measurement of irradiation dose versus source/component distance, using a calibrated equipment. - Use of ALANINE dosimeters, placed on the support of the irradiated components. - Assembly and polarization of components during the irradiations. Selection of the irradiator. - Measurement of the irradiated components's parameters, using the competences of the societies: - GenRad: GR130 tests equipement placed in the DEIN/SIR-CEN SACLAY. - Laboratoire Central des Industries Electriques (LCIE): GR125 tests equipment and this associated programmes test [fr

  19. Effect of low-dose (1 kGy) gamma radiation and selected phosphates on the microflora of vacuum-packaged ground pork

    International Nuclear Information System (INIS)

    Ehioba, R.M.

    1987-01-01

    The effects of low-dose (1 kGy) gamma radiation and selected phosphates on the microbiology of refrigerated, vacuum-packaged ground pork were studied. Low-dose gamma radiation reduced the numbers of naturally occurring mesophiles, psychrotrophs, and anaerobes. The effect of low-dose radiation on the populations of lactic acid bacteria was minimal. On storage of the irradiated vacuum-packaged ground pork at 5 0 C, there was a partial bacterial recovery, suggesting sublethal bacterial injury due to irradiation. When 10 7 CFU/g of meat is taken to be the level beyond which the meat would be considered spoiled, uninoculated, vacuum-packaged ground pork treated with 1 kGy (100 krad) of gamma radiation had 3.5 more days of shelf-life in terms of psychrotrophic total counts. In relation to anaerobic bacterial numbers, meat shelf-life was extended 2.5 days, while the shelf-life of meat was extended 1 day in terms of aerobic mesophilic bacteria. Irradiation prolonged shelf-life in inoculated (10 5 CFU/g) meat for 1.0-1.5 days. Addition of 0.4% sodium acid pyrophosphate (SAPP) contributed 2 additional days to inoculated, irradiated vacuum-packaged ground pork shelf-life. However, SAPP had no added effect on naturally occurring microflora. Irradiation greatly decreased the numbers of gram-negative microorganisms, resulting in predominance of the gram-positive, nonsporeforming Lactobacillus and coryneform bacteria

  20. Estimation of the radiation strength, dose equivalent and mean gamma-ray energy form p+ sup 2 sup 3 sup 8 U fission products

    CERN Document Server

    Kawakami, H

    2003-01-01

    On 100 isobars from 72 to 171 mass number, the radiation strength, dose equivalent and mean gamma-ray energy from p+ sup 2 sup 3 sup 8 U fission products at Tandem accelerator facility were estimated on the basis of data of proton induced fission mass yield by T. Tsukada. In order to control radiation, the decay curves of radiation of each mass after irradiation were estimated and illustrated. These calculation results showed 1) the peak of p+ sup 2 sup 3 sup 8 U fission products is 101 and 133 mass number. 2) gamma-ray strength of target ion source immediately after irradiation is 3.12x10 sup 1 sup 1 (Radiation/s) when it repeated 4 cycles of UC sub 2 (2.6 g/cm sup 2) target radiated by 30 MeV and 3 mu A proton for 5 days and then cooled for 2 days. It decreased to 3.85x10 sup 1 sup 0 and 6.7x10 sup 9 (Radiation/s) after one day and two weeks cooling, respectively. 3) Total dose equivalent is 3.8x10 sup 4 (mu S/h) at 1 m distance without shield. 4) There are no problems on control the following isobars, beca...

  1. Automation of the monitoring in real time of the absorbed dose rate in air due to the environmental gamma radiation in Cuba

    International Nuclear Information System (INIS)

    Dominguez L, O.; Capote F, E.; Carrazana G, J.A.; Manzano de Armas, J.F.; Alonso A, D.; Prendes A, M.; Zerquera, J.T.; Caveda R, C.A.; Kalberg, O.; Fabelo B, O.; Montalvan E, A.; Cartas A, H.; Leyva F, J.C.

    2006-01-01

    The Center of Protection and Hygiene of the Radiations (CPHR) like center rector of the National Net of Environmental Radiological Surveillance (RNVRA), it has strengthened their detection capacity and of answer before a situation of radiological emergency. The measurements of the absorbed dose rate in air due to the environmental gamma radiation in the main stations of the Net are obtained in real time and the CPHR receives the data coming from these posts at one time relatively short. To improve the operability of the RNVRA it was necessary to complete the facilities of existent monitoring using 4 automatic measurement stations with probes of gamma detection, implementing in this way a measurement system on real time. On the other hand the software were developed: GenironProbeFech, to obtain the data of the probes, DataMail for the shipment of the same ones by electronic mail and GammaRed that receives and processes the data in the rector center. (Author)

  2. The low dose gamma ionising radiation impact upon cooperativity of androgen-specific proteins.

    Science.gov (United States)

    Filchenkov, Gennady N; Popoff, Eugene H; Naumov, Alexander D

    2014-01-01

    The paper deals with effects of the ionising radiation (γ-IR, 0.5 Gy) upon serum testosterone (T), characteristics of testosterone-binding globulin (TeBG) and androgen receptor (AR) in parallel with observation of androgen (A) responsive enzyme activity - hexokinase (HK). The interdependence or relationships of T-levels with parameters of the proteins that provide androgenic regulation are consequently analyzed in post-IR dynamics. The IR-stress adjustment data reveal expediency of TeBG- and AR-cooperativity measurements for more precise assessments of endocrine A-control at appropriate emergencies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Gonad, bone marrow and effective dose to the population of more than 90 towns and cities of Iran, arising from environmental gamma radiation

    International Nuclear Information System (INIS)

    Bahreyni Toossi, M.T.; Bayani, S.H.; Abdolrahimi, A.; Yarahmadi, M.; Aghamir, A.; Jomehzadeh, A.; Hagh Parast, M.; Tamjidi, A.

    2008-01-01

    Natural radiation environment and it's biological impacts on human life has not received appreciable attention in Iran. Before 1996 only a few sporadic studies had been carried out, but no systematic study of normal back ground had been conducted. Since 1996 assessment of environmental gamma radiation dose in residential areas of Iranian towns and cities was defined as a long term goal in our center. Till now measurements of annual dose rates have been accomplished for 10 counties. As a practical method and based on the results of a pilot study, in order to attribute the final results to the whole residential area of a town five stations were selected for every town. The location of individual station was studied closely to comply with recommended conditions in the literature. RDS-110 was employed to measure gamma dose rate for one hour. Practically huge numbers of dose rate figures were recorded, they were substantially summarized to estimate average dose rate. Average annual dose rates plus conversion coefficients were employed to estimate gonad, bone marrow, equivalent and effective dose. In the vast studied area average out-door gamma dose rate is varying from 35 nSvh -1 to 205 nSvh -1 . Minimum and maximum annual bone marrow and gonad dose equivalent attributed to environmental gamma are 0.24 mSvy -1 (for both tissues) and 1.44 and 1.46 mSvy -1 respectively. Effective dose of inhabitants arising from out-door gamma is varying by 6 folds from 0.21 to 1.26 mSvy -1 . The largest and smallest population weighted dose are equal to 0.35 and 1.00 mSvy -1 . Average gonad and bone marrow doses for north Khorasan, Boshehr and Hormozgan are less than the corresponding values for normal area. On the other hand inhabitants of the studied area receive a dose higher than the world average, except those who live in Hormozgan and Boshehr. (author)

  4. gamma. radiation of ionium

    Energy Technology Data Exchange (ETDEWEB)

    Curie, I

    1948-12-08

    Following the work of Ward (Proc Cambridge Phil Soc 35 322(1939)), the ..gamma..-radiation of ionium (from an IoTh preparation) was studied with the aid of Ta and W screens, and an aluminum counter. The screen measurements confirmed Ward's findings of two radiations, of 68 keV and of about 200 keV. The number of quanta per second of each radiation was determined with the counter, which has been calibrated on certain L lines of radium. The global quanta number of L lines of ionium was also determined. The results were as follows: 0.7 quanta ..gamma.. of 68 keV for 100 ..cap alpha..-particles; 0.2 quanta ..gamma.. of 200 keV for 100 ..cap alpha..-particles; 10 quanta L for 100 ..cap alpha..-particles. These data, which show an important internal conversion, agree with the findings of Teillac (Compt Rend 227 1227 (1948)), who investigated the ..beta..-radiation of ionium. It is the radiation 68 keV which is highly converted. On the other hand, these results do no agree with the data on the fine structure of ionium found by Rosenblum, Valadares, and Vial (Compt Rend 227 1088(1948)).

  5. Gamma response study of radiation sensitive MOSFETs for their use as gamma radiation sensor

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Saurabh; Kumar, A. Vinod [Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai (India); Aggarwal, Bharti; Singh, Arvind; Topkar, Anita, E-mail: anita@barc.gov.in [Electronics Division, Bhabha Atomic Research Centre, Mumbai (India)

    2016-05-23

    Continuous monitoring of gamma dose is important in various fields like radiation therapy, space-related research, nuclear energy programs and high energy physics experiment facilities. The present work is focused on utilization of radiation-sensitive Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs) to monitor gamma radiation doses. Static characterization of these detectors was performed to check their expected current-voltage relationship. Threshold voltage and transconductance per unit gate to source voltage (K factor) were calculated from the experimental data. The detector was exposed to gamma radiation in both, with and without gate bias voltage conditions, and change in threshold voltage was monitored at different gamma doses. The experimental data was fitted to obtain equation for dependence of threshold voltage on gamma dose. More than ten times increase in sensitivity was observed in biased condition (+3 V) compared to the unbiased case.

  6. Study of gamma radiation induced damages and variation of oxygen enhancement ratio with radiation dose using Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Nairy, R.K.; Yerol Narayana; Bhat, N.N.; Anjaria, K.B.; Sreedevi, B.; Sapra, B.K.

    2014-01-01

    In the present study, an attempt has been made to quantify Oxygen Enhancement Ratio (OER) and variation of OER as a function of dose with experimental and theoretical formulations using Saccharomyces cerevisiae D7, X2180 and rad 52. The study confirms that, the variation of OER with dose depends upon type of cell and repair proficiency of cells. A theoretical model has been formulated to estimate OER values. With the help of this model, OER value for any dose can be calculated in the exponential region of the survival curve without actually extending the experiment in that dose region. (author)

  7. Effects of Low Dose Gamma Radiation on the Formation of Shikonon Derivatives in Callus Cultures of Lithospermum erythrorhizon

    International Nuclear Information System (INIS)

    Hwang, H.Y.; Lee, Y.B.; Kim, J.S.

    2003-01-01

    The effects of low dosage r-radiation on the cell growth and the formation of shikonin derivatives were investigated in callus cultures of Lithospermum erythrorhizon under different medium and light conditions. Gamma radiation significantly affected the cell growth and formation of shikonin derivatives, depending on the culture conditions. In the cell cultures grown on M09 medium, 2 Gy and 16 /Gy of r-radiation increased the calli growth and the formation of shikonin derivatives, respectively under 16 hr day light condition

  8. Quantitative dose-response of growth and development in Arabidopsis thaliana exposed to chronic gamma-radiation

    International Nuclear Information System (INIS)

    Daly, K.; Thompson, K.H.

    1975-01-01

    The response of Arabidopsis thaliana (L.) Heynh. (Cruciferae) to a gradient of chronic gamma-radiation was examined under field conditions. Plants that were initially introduced to the gamma field as dry seeds received exposures of 1.34 to 18 800R/20 hour day from the time of seed germination. Regression analysis demonstrated a significant, but non-linear, response for three variables, number of seedlings emerging, number of plants flowering, and plant volume; the response of a fourth variable, number of leaves per plant, was not related to daily exposure. LD 50 values ranged from 66R/20 hour day for plant volume to 1231R/20 hour day for seedling emergence. Flowering and plant volume were the most sensitive indicators of radiation exposure. The demonstration of a variable threshold at low levels of exposure indicates that in nature A. thaliana may be exposed to environmental radiation throughout its life-cycle without significant modification of growth or development. (author)

  9. Nonmonotonous changes of thymus nuclei lipid metabolism upon chronic gamma-radiation of rats at a dose-rate of 3 c Gy/Day

    International Nuclear Information System (INIS)

    Kulagina, T.P.; Kolomijtseva, I.K.; Moiseeva, S.A.; Kuzin, A.M.

    2000-01-01

    The dynamics of changes in the thymus nuclei lipid metabolism under chronic gamma-radiation in low doses with the dose rate of 3 cGy/day is studied. It is shown, that at the 25 cGy dose rate there takes place activation of exchange in the fatly-acid part of the phospholipid molecule with simultaneous activation of the cholesterol and fatty acids synthesis. The synthesis of cholesterol and fatty acids at 50 cGy remains activated, whereas metabolism of the fatty-acid part of the phospholipids molecule is sharply depressed. The identified changes reveal the similarity with the processes, proceeding by the apoptose induction. At the same time the dynamics of the thymocyte nuclei lipid exchange in the process of adaptation to the long radiation effect as nonmonotonous metabolic response to low dose impact is characterized for the first time [ru

  10. Radiation transport simulation in gamma irradiator systems using E G S 4 Monte Carlo code and dose mapping calculations based on point kernel technique

    International Nuclear Information System (INIS)

    Raisali, G.R.

    1992-01-01

    A series of computer codes based on point kernel technique and also Monte Carlo method have been developed. These codes perform radiation transport calculations for irradiator systems having cartesian, cylindrical and mixed geometries. The monte Carlo calculations, the computer code 'EGS4' has been applied to a radiation processing type problem. This code has been acompanied by a specific user code. The set of codes developed include: GCELLS, DOSMAPM, DOSMAPC2 which simulate the radiation transport in gamma irradiator systems having cylinderical, cartesian, and mixed geometries, respectively. The program 'DOSMAP3' based on point kernel technique, has been also developed for dose rate mapping calculations in carrier type gamma irradiators. Another computer program 'CYLDETM' as a user code for EGS4 has been also developed to simulate dose variations near the interface of heterogeneous media in gamma irradiator systems. In addition a system of computer codes 'PRODMIX' has been developed which calculates the absorbed dose in the products with different densities. validation studies of the calculated results versus experimental dosimetry has been performed and good agreement has been obtained

  11. Gonad, bone marrow and effective dose to the population of more than 90 towns and cities of Iran, arising from environmental gamma radiation

    International Nuclear Information System (INIS)

    Bahreyni Toossi, M. T.; Bayani, Sh.; Yarahmadi, M.; Aghamir, A.; Jomehzadeh, A.; Hagh Parast, M.; Tamjidi, A.

    2009-01-01

    Since 1996 the assessment of environmental gamma radiation dose in residential areas of Iranian towns and cities has been accomplished for 10 counties. As a practical method and based on the results of a pilot study, in order to attribute the final results to the whole residential area of a town five stations were selected for every town. The location of individual station was studied closely to comply with recommended conditions in the literature. Materials and Methods: RDS-110 was employed to measure gamma dose rate for one hour. Average annual dose rates plus conversion coefficients were employed to estimate gonad, bone marrow, equivalent and effective dose. Result: Minimum and maximum annual bone marrow and gonad dose equivalent attributed to environmental gamma are 0.24 mSvy -1 (for both tissues) and 1.44 and 1.46 mSvy -l , respectively. Conclusion: Average gonad and bone marrow doses for North Khorasan, Boshehr and Hormozgan provinces were less than the corresponding values for normal area.

  12. Target and peripheral dose from radiation sector motions accompanying couch repositioning of patient coordinates with the Gamma Knife® Perfexion™

    International Nuclear Information System (INIS)

    Tran, Tuan-Anh; Wu, Vincent; Malhotra, Harish; Steinman, James P.; Prasad, Dheerendra; Podgorsak, Matthew B.

    2011-01-01

    The GammaPlan ™ treatment planning system (TPS) does not fully account for shutter dose when multiple shots are required to deliver a patient’s treatment. The unaccounted exposures to the target site and its periphery are measured in this study. The collected data are compared to a similar effect from the Gamma Knife ® model 4C. A stereotactic head frame was attached to a Leksell ® 16 cm diameter spherical phantom; using a fiducial-box, CT images of the phantom were acquired and registered in the TPS. Measurements give the relationship of measured dose to the number of repositions with the patient positioning system (PPS) and to the collimator size. An absorbed dose of 10 Gy to the 50% isodose line was prescribed to the target site and all measurements were acquired with an ionization chamber. Measured dose increases with frequency of repositioning and with collimator size. As the radiation sectors transition between the beam on and beam off states, the target receives more shutter dose than the periphery. Shutter doses of 3.53±0.04 and 1.59±0.04 cGy/reposition to the target site are observed for the 16 and 8 mm collimators, respectively. The target periphery receives additional dose that varies depending on its position relative to the target. The radiation sector motions for the Gamma Knife ® Perfexion ™ result in an additional dose due to the shutter effect. The magnitude of this exposure is comparable to that measured for the model 4C

  13. Sewage sterilization through gamma radiation

    International Nuclear Information System (INIS)

    Vieira, D.V.; Teixeira, W.M.S.; Silva, F.C.A. da

    2017-01-01

    Lack of sewage treatment and adequate sanitation conditions can contribute to the proliferation of numerous parasitic and infectious diseases in addition to water degradation. Approximately fifty types of infections can be transmitted from a sick to a healthy person through different pathways involving human excreta. Untreated sewage can contaminate water, food, hands, soil, etc. Epidemics of certain diseases such as typhoid, cholera, dysenteries, etc., and countless cases of worms are responsible for high mortality rates in third world countries. In the work the different techniques of sewage treatment by disinfestation and sterilization were analyzed, highlighting the use and the advantages of the gamma radiation as well as the aspects of the radiological protection involved. The technique of sewage sterilization using gamma radiation is a method of controlling bacteria and microorganisms. It is estimated that more than 200 large irradiators are in operation worldwide, of which 5 are in Brazil, for general sterilization use. These facilities use a large amount of radioactive material, in the order of millions of Becquerel, for sterilization with high doses of radiation, which can generate lethal doses in a few minutes. These industrial facilities use Cobalt-60, being classified by the International Atomic Energy Agency - IAEA as Category 1 of high risk, and must possess a high level of radiological protection to carry out the sterilization, standing out the defense in depth. Specific legislation on radiological protection should be drafted for safe work and avoid future radiation accidents

  14. Sensory techniques for measuring differences in California navel oranges treated with doses of gamma-radiation below 0.6 Kgray

    International Nuclear Information System (INIS)

    O'Mahony, M.; Goldstein, L.R.

    1987-01-01

    Navel oranges from California were given low post harvest doses of gamma radiation: 0.32-0.37 and 0.52-0.60 KGy (32-37 and 52-60 Krad); they were compared with nonirradiated controls for visual appearance, flavor by mouth, odor, taste and taste after sweetness suppression by gymnema sylvestre. Practiced judges were used as an analytical tool, with minimum cross-sensory interference, while untrained subjects were used to determine whether changes might be distinguished by nonexperts. Differences were found in appearance, flavor, taste and odor although they were less extreme at the lower dose. Untrained judges could discriminate the juice at the higher irradiation level only

  15. Influence of the anthropogenic changes of gamma dose radiation connected connected with uranium mining upon selected plants

    International Nuclear Information System (INIS)

    Solecki, A. T.; Wislocka, M.A.

    2000-01-01

    The situation of flora in the regions with expressive anthropogenic changes in the background of gamma radiation and concentration of the radon in atmospheric air was observed. The content of heavy metals in the depth of the anomaly terrain was analyzed. The analyses of the selected radionuclides in plant ash by method in thin layer were performed. The concentration of radionuclides and situation of flora was correlated. (authors)

  16. Effect of cross-linkage by gamma radiation in heavy doses to low wear polyethylene in total hip prostheses

    International Nuclear Information System (INIS)

    Oonishi, H.

    1996-01-01

    Wear, frictional torque and creep deformity of UHMWPE sockets crosslinked by gamma radiation of 100, 500 and 1000 Mrad in combination with 28 mm alumina heads, were measured using a hip simulator (under constant load 250 kgf with lubrication of saline solution). Hardness and hydrophilic increased and creep deformity decreased as a result of gamma radiation. The initial wear (decrement of the thickness) of the socket with radiation of 0, 100, 500 and 1000 Mrad was, 150 μm, 100 μm, 70 μm and 50 μm, respectively. The time to steady-state wear at 0, 100, 5000 and 1000 Mrad was about 0.15 million, 0.15 million, 0.1 million, and 0.05 million cycles, respectively. The steady-state wear (decrement of the thickness) of the socket without and with radiation was 200 μm/million cycles and less than 20 μm/million cycles, respectively. Rotational torque was under 0.65 Nm in every case. Swing frictional torque at radiation levels of 0, 100, 500 and 1000 MRad were 1.60-2.84 Nm, 3.24-9.02 Nm, 5.23-8.78 Nm, and 2.51-6.79 Nm, respectively. (Author)

  17. Evaluation of personal dose equivalent 'HP(d)' in a external individual monitoring system for X and gamma radiation

    International Nuclear Information System (INIS)

    Santoro, C.; Antonio Filho, J.; Santos, M.A.P.

    2007-01-01

    The good of individual monitoring for external radiation is the assessment of occupational exposure from X and γ radiations in order to assure that the radiological conditions of the workplace are acceptable, safe and satisfactory. The evaluation of radiations doses for workers must not exceed dose limits specified for workers, according to national regulatory agencies. Nowadays, there are two external monitoring systems in use, both based on ICRU definitions. In the conventional system, the workers doses are evaluated in terms of Hx. The personal dosimeter is worn over chest surface and it is calibrated in function of air kerma. In the new system, the workers doses are evaluated in terms of HP(d) and the personal dosimeter is calibrated in function of phantom doses. The aim of this paper is to adapt an external dosimetry laboratory (based on photographic dosimetry) to evaluate the personal dosimeters in terms of HP(d). In this way, a simple methodology, based on linear programming, was utilized. In this adaptation, calibration curves were obtained for radiation qualities (W and N series) described by International Organization for Standardization (ISO 4037-1, 1995). These calibration curves offer a better accuracy on dose determinations and energy below 140 keV, improving the quality of service rendered the society. (author)

  18. Assessment of background gamma radiation levels using airborne gamma ray spectrometer data over uranium deposits, Cuddapah Basin, India - A comparative study of dose rates estimated by AGRS and PGRS.

    Science.gov (United States)

    Srinivas, D; Ramesh Babu, V; Patra, I; Tripathi, Shailesh; Ramayya, M S; Chaturvedi, A K

    2017-02-01

    The Atomic Minerals Directorate for Exploration and Research (AMD) has conducted high-resolution airborne gamma ray spectrometer (AGRS), magnetometer and time domain electromagnetic (TDEM) surveys for uranium exploration, along the northern margins of Cuddapah Basin. The survey area includes well known uranium deposits such as Lambapur-Peddagattu, Chitrial and Koppunuru. The AGRS data collected for uranium exploration is utilised for estimating the average absorbed rates in air due to radio-elemental (potassium in %, uranium and thorium in ppm) distribution over these known deposit areas. Further, portable gamma ray spectrometer (PGRS) was used to acquire data over two nearby locations one from Lambapur deposit, and the other from known anomalous zone and subsequently average gamma dose rates were estimated. Representative in-situ rock samples were also collected from these two areas and subjected to radio-elemental concentration analysis by gamma ray spectrometer (GRS) in the laboratory and then dose rates were estimated. Analyses of these three sets of results complement one another, thereby providing a comprehensive picture of the radiation environment over these deposits. The average absorbed area wise dose rate level is estimated to be 130 ± 47 nGy h -1 in Lambapur-Peddagattu, 186 ± 77 nGy h -1 in Chitrial and 63 ± 22 nGy h -1 in Koppunuru. The obtained average dose levels are found to be higher than the world average value of 54 nGy h -1 . The gamma absorbed dose rates in nGy h -1 were converted to annual effective dose rates in mSv y -1 as proposed by the United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR). The annual average effective dose rates for the entire surveyed area is 0.12 mSv y -1 , which is much lower than the recommended limit of 1 mSv y -1 by International Commission on Radiation protection (ICRP). It may be ascertained here that the present study establishes a reference data set (baseline) in these areas

  19. Use of low doses of cobalt 60 gamma radiation on beet (Beta vulgaris L.), carrot (Daucus carota L.) and radish (Raphanus sativus L.) seed to stimulate increase yield

    International Nuclear Information System (INIS)

    Bovi, Jose Eduardo

    2000-01-01

    The research had the aim of evaluating the effects of low doses of Cobalt-60 gamma radiation on seeds of radish (Raphanus sativus L.) cultiva Champion, cultivars Nantes Forto (european origin) and Brasilia (Rio Grande do Sul origin) carrot (Daucus carota L. var. sativus (Hoffm.) Thell), and red beet (Beta vulgaris L.) cultivar Tall Top Early Wonder before sowing, its effects on plant growth, on the yield and roots storage of two tillages: with sowing in the same day of radiation and six days after radiation seeds. The data showed that the seeds radiation did not interfered negatively on plants growth, and the species presented differences as roots production and doses on both plantation: radish with 5,0 Gy and 2,5 Gy doses respectively to the first and the second sowings, Brasilia carrot with 2,5 Gy dose to both sowings. Nantes carrot with 2,5 Gy and 5,0 Gy respectively to the first and the second sowings, and beet with 7,5 Gy and 5,0 Gy respectively to the first and the second plantations. There is not statistics difference by Tukey test (5% and 1%) and none relation between seeds radiation and loss weight on roots storage. (author)

  20. Analysis of FT-IR for dosimetric characterization of poly(vinylidene fluoride - hexafluoropropylene) irradiated with high doses of gamma radiation

    International Nuclear Information System (INIS)

    Liz, Otavio Souza Rocha; Medeiros, Adriana de Souza

    2011-01-01

    Polymeric materials when exposed to ionizing radiation undergo changes such as the crosslinking and chain oxidation. Recently, the optical absorption intensities in the ultraviolet visible region (273 nm) due to radio- induction of conjugated C=C bonds in P(VDF-TrFE) copolymers has been successfully used for high dose dosimetry purposes in gamma fields ranging from 0.1 to 200 kGy. In this context, the interest of performing a systematic investigation on another fluorinated copolymer of PVDF, the (Polyvinylidene fluoride - hexa fluoro propylene) [P(VDF- HFP)] has come to light, not only for UV-VIS range but also for the near and medium infrared ranges. In this investigation FTIR and UV-Vis spectra, acquired before and after irradiation, were used to investigate the relationship between optical absorbance and delivered gamma doses ranging from 100 to 3,000 kGy. The results indicate that the absorption band at 1729 cm-1, originated by the chain oxidation through the radioinduction of C=O bonds, presents an unambiguous behavior with the delivered gamma doses in a very large extension, ranging from 0 to 1,000 kGy. This results lead to conclude that P(VDF-HFP) copolymer shows excellent dosimetric properties which make it able to be investigated as a high dose dosimeter

  1. SGR-76 gamma radiation level indicator

    International Nuclear Information System (INIS)

    Chubinskij-Nadezhdin, I.V.

    1978-01-01

    The design of a gamma-radiation level indicator is described; the instrument is part of a mobile radiometric laboratory (MRL). The design of the instrument permits gamma-radiation dose rates recording at 0.2-200 R/hr, and signals on gamma-background levels. The instrument has two separate threshold levels of signalling actuation. The light signalling at the first level is precautionary, and the sound signalling at the second level indicates the necessity of taking a decision as to whether or not the MRL can remain in the gamma-radiation field. Halogenic counters operating in a current mode are used as detectors. The basic error in recording the dose rate amounts to +-25%. Overall dimensions of the instrument 150x280x100 mm; weight less than 2.5 kg

  2. Calculating gamma dose factors for hot particle exposures

    International Nuclear Information System (INIS)

    Murphy, P.

    1990-01-01

    For hot particle exposures to the skin, the beta component of radiation delivers the majority of the dose. However, in order to fully demonstrate regulatory compliance, licenses must ordinarily provide reasonable bases for assuming that both the gamma component of the skin dose and the whole body doses are negligible. While beta dose factors are commonly available in the literature, gamma dose factors are not. This paper describes in detail a method by which gamma skin dose factors may be calculated using the Specific Gamma-ray Constant, even if the particle is not located directly on the skin. Two common hot particle exposure geometries are considered: first, a single square centimeter of skin lying at density thickness of 7 mg/cm 2 and then at 1000 mg/cm 2 . A table provides example gamma dose factors for a number of isotopes encountered at power reactors

  3. Electrical Conductivity of Gamma Irradiated Aqueous Urea Solution and its Application for Determination of Absorbed Radiation Dose; Sife-Eldeen Dosimeter

    International Nuclear Information System (INIS)

    Sife- Eldeen, Kh.A.

    2008-01-01

    In This Study, the radiation induced electrical conductivity (RIC) of aqueous urea solutions was investigated after gamma radiolysis. It was found that the RIC depends on preirradiation urea concentration, absorbed radiation dose and storage time. At the same absorbed dose, RIC increases as preirradiation urea concentration increases. The RIC change of aqueous urea solutions reaches a maximum value at 3.5 M aqueous urea solutions. RIC of 0.133 and 3.5 M aqueous urea solutions as a function of dose, have been investigated in the range between 2.18 and 119.4 kGy. RIC of the 0.133 and 3.5 M aqueous urea solutions increased linearly with increasing dose (R 2 =0.9963, 0.9972 respectively). The calibration factors was found to be 2.1448 and 9.53 μS/kGy for sets with 0.133 and 3.5 M urea respectively .The coefficient of variation CV %, associated with RIC measurement of 3.5 M aqueous urea solution as a function of absorbed radiation dose was found to be 1.8025% and the uncertainty was found to be 3.6 % and 5.4 % for 95 % and 99 % confidence levels, respectively. The effective atomic number of 3.5 M aqueous urea solutions is 6.58, which indicates tissue equivalency of this system. The RIC values of 3.5 M aqueous urea solutions were found to be relatively stable over storage period of three weeks at 0 degree C. Accordingly, this system could be considered as a promising radiation-sensitive material for dosimetry of gamma rays in both technical and research fields

  4. Inherited sterility in Eldana saccharina Walker (Lepidoptera: Pyralidae): effect of sub-sterilizing doses of gamma radiation on mating, fecundity and fertility

    International Nuclear Information System (INIS)

    Annoh, C.E.; Adabie-Gomez, D.A. Biotechnology and Nuclear Agriculture Research Institute; Botchey, M.A.; Mensah, B.A.

    2003-01-01

    Mature pupae (6-8 days old) of Eldana saccharina were exposed to increasing sub-sterilizing doses of ionizing gamma radiation in the range of 80-180 Gy. In the parental (P) generation, emerged male and female moths were out-crossed with untreated moths of the opposite sex. Reciprocal crosses between progeny of treated and untreated moths were also made in the F1 generation. In both generations, radiation doses used did not have any significant effect on mating behaviour of adults E. saccharina. There was also no significant difference in the mean number of spermatophores (approximately 1.0 per female) transferred by males to females during copulation among treated and control crosses. Fecundity in the parental generation was reduced by 40-44% in crosses between treated males and untreated females without any clear dose dependence. In the reciprocal crosses, however, fecundity considerably decreased with the increasing dose of radiation. The dose-dependent decreased of fecundity, similar in both reciprocal crosses, was also observed in F1 generation. Increasing doses of radiation generally resulted in decreasing fertility of treated moths in both the P and F1 generations. There was, however, a remarkable difference between reciprocal crosses. While radiation induced only partial sterility of treated P males even at the highest dose (180 Gy), treated P females exhibited a high sterility at 100 Gy. In both F1 crosses, fertility was lower than in treated P males, and F1 males exhibited a higher level of inherited sterility than F1 females. The results demonstrate a potential of using inherited sterility in integrated pest management programme to suppress the pest population of E. saccharina and other related stemborer species (author)

  5. Induction of genetic instability in ρ53 in primary cultures of normal human urothelium exposed low-dose of gamma radiation

    International Nuclear Information System (INIS)

    Colucci, S.; Mothersill, C.; Seymour, C.; Harney, J.; Gamble, S.; Arrand, J.

    1997-01-01

    We have previously shown that primary explant cultures of human urothelium exposed to low doses of gamma radiation subsequently exhibit a high level of stable P53 but it was not clear from those studies whether this protein stabilisation occurred through epigenetic events or as a result of mutation. In these experiments, primary urothelium cultures from five different patients were exposed to 0.5 and 5 Gy γ- radiation from a 60 Cobalt source and allowed to grow for 7- 10 division cycles to allow development of any radiation-induced, non lethal changes in the urothelial cells. C-myc, Bcl-2, and stable P53 protein expression was found to be elevated in cultures following both radiation doses. Following 0.5 Gy exposure, the cultures also developed multiple distinct 'foci' of rapidly-dividing cells which strongly over-expressed P53. These grew on a background of morphologically normal cells. When such foci were selectively analysed for their p53 mutation status by PCR-SSCPE, there was evidence that they contained cells which had developed changes to thr p53 gene post-irradiation. These changes appeared to occur more frequently in focal cells than in cells of normal morphological appearance in the same culture. DNA sequence analysis of the p53 gene in 0.5 Gy-induced foci displayed frame shift mutations in some cases. These results may have mechanistic importance given the controversy regarding low-dose radiation effects and p53-related genomic instability. (authors)

  6. Registration of radiation doses

    International Nuclear Information System (INIS)

    2000-02-01

    In Finland the Radiation and Nuclear Safety Authority (STUK) is maintaining the register (called Dose Register) of the radiation exposure of occupationally exposed workers in order to ensure compliance with the principles of optimisation and individual protection. The guide contains a description of the Dose Register and specifies the responsibilities of the party running a radiation practice to report the relevant information to the Dose Register

  7. Radiation mutagenesis in lavender. I.Dose and emissive power as affecting the radiosensitivity of lavender seeds in gamma-ray treatment

    International Nuclear Information System (INIS)

    Tsvetkov, R.

    1977-01-01

    The radiosensitivity has been investigated of dormant seeds of the widely distributed aboriginal Hemus and Karlovo varieties and of the Soviet Stepnaya lavender variety in treatment with gamma rays using 60 Co. Doses within 1 to 100 kRad are applied at different emissive power of the emitter. Both irradiated and nonirradiated control seeds are gibberellic acid treated. The dynamics of seed sprouting is followed up. The number of survived plants and peculiarities of their growth are registered. The radiosensitivity of Lavandula vera D.C. seeds is modified by the emissive power in equal doses applied. Stepnaya variety showed highest resistance, followed by Karlovo and Hemus varieties. Doses are ascertained with a stimulating, inhibiting, semilethal and lethal effect in regard to the separate varietoes. Both stimulation and injuring prove to be of saltatory character. The radiation injuring of doses with an inhibitory, semilethal and lethal effect positively correlate with the dose of all tested emissive powers of the gamma-emitter. (author)

  8. Effects of gamma radiation in annatto seeds

    International Nuclear Information System (INIS)

    Franco, Camilo F. de Oliveira; Arthur, Valter; Arthur, Paula B.; Harder, Marcia N.C.; Filho, Jose C.; Neto, Miguel B.

    2015-01-01

    The annatto bixin has emerged as a major source of natural dyes used in the world notably by the substitution of synthetics harmful to human health and ecologic tendency in obtaining industrial products free of additives with applications in industries textiles; cosmetics; pharmaceutical and food mainly. The aim of this research was to obtain increased of germination rate and dormancy breaking on annatto seeds by gamma radiation. Annatto dry seeds were exposed to low doses of gamma radiation from source of Cobalt-60, type Gammecell-220, at 0.456 kGy/hour dose rate. In order to study stimulation effects of radiation on germination rate and dormancy breaking in the seeds. Five treatments with gamma radiation doses were applied as follows: 0 (control); 100; 125; 150 and 175 Gy. After irradiation the annatto seeds were planted as for usual seed production. According to the results obtained in this experiment we can conclude that the low doses of gamma radiation utilized on the annatto seeds did not presented significantly effect on the germination of plants. But the best dose to increase the germination of seeds was 150 Gy. (author)

  9. Effects of gamma radiation in annatto seeds

    Energy Technology Data Exchange (ETDEWEB)

    Franco, Camilo F. de Oliveira, E-mail: camilo.urucum@hotmail.com [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA/EMEPA), Joao Pessoa, PB (Brazil); Arthur, Valter; Arthur, Paula B., E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Harder, Marcia N.C., E-mail: marcia.harder@fatec.sp.gov.br [Centro Paula Souza, Curso Superior de Tecnologia em Bicombustiveis (FATEC), Piracicaba, SP (Brazil); Filho, Jose C.; Neto, Miguel B., E-mail: jorgecazefilho@yahoo.com.br [Empresa Estadual de Pesquisa Agropecuaria da Paraiba (EMEPA), Joao Pessoa, PB (Brazil)

    2015-07-01

    The annatto bixin has emerged as a major source of natural dyes used in the world notably by the substitution of synthetics harmful to human health and ecologic tendency in obtaining industrial products free of additives with applications in industries textiles; cosmetics; pharmaceutical and food mainly. The aim of this research was to obtain increased of germination rate and dormancy breaking on annatto seeds by gamma radiation. Annatto dry seeds were exposed to low doses of gamma radiation from source of Cobalt-60, type Gammecell-220, at 0.456 kGy/hour dose rate. In order to study stimulation effects of radiation on germination rate and dormancy breaking in the seeds. Five treatments with gamma radiation doses were applied as follows: 0 (control); 100; 125; 150 and 175 Gy. After irradiation the annatto seeds were planted as for usual seed production. According to the results obtained in this experiment we can conclude that the low doses of gamma radiation utilized on the annatto seeds did not presented significantly effect on the germination of plants. But the best dose to increase the germination of seeds was 150 Gy. (author)

  10. Effects of gamma radiation in soybean

    International Nuclear Information System (INIS)

    Franco, Jose Gilmar; Franco, Suely Salumita Haddad; Arthur, Valter; Arthur, Paula Bergamin; Franco, Caio Haddad

    2015-01-01

    The degree of radiosensitivity depends mostly on the species, the stage of the embryo at irradiation, the doses employed and the criteria used to measure the effect. One of the most common criteria to evaluate radiosensitivity in seeds is to measure the average plant production. Soya dry seeds were exposed to low doses of gamma radiation from source of Cobalt-60, type Gammecell-220, at 0.245 kGy dose rate. In order to study stimulation effects of radiation on germination, plant growth and production. Five treatments radiation doses were applied as follows: 0 (control); 25; 50; 75 and 100 Gy. Seed germination and harvest of number of seeds and total production were assessed to identify occurrence of stimulation. Soya seeds and plants were handled as for usual seed production in Brazil. The low doses of gamma radiation in the seeds that stimulate the production were doses of 25, 50 and 75 Gy. There are evidences that the use of low doses of gamma radiation can stimulate germination and plant production. (author)

  11. Effects of gamma radiation in soybean

    Energy Technology Data Exchange (ETDEWEB)

    Franco, Jose Gilmar; Franco, Suely Salumita Haddad; Arthur, Valter; Arthur, Paula Bergamin, E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Franco, Caio Haddad [Centro Nacional de Pesquisa em Energia e Materiais (LNBio/CNPEM), Campinas, SP (Brazil). Laboratorio Nacional de Biociencias; Villavicencio, Anna Lucia, E-mail: zegilmar60@gmail.com, E-mail: gilmita@uol.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The degree of radiosensitivity depends mostly on the species, the stage of the embryo at irradiation, the doses employed and the criteria used to measure the effect. One of the most common criteria to evaluate radiosensitivity in seeds is to measure the average plant production. Soya dry seeds were exposed to low doses of gamma radiation from source of Cobalt-60, type Gammecell-220, at 0.245 kGy dose rate. In order to study stimulation effects of radiation on germination, plant growth and production. Five treatments radiation doses were applied as follows: 0 (control); 25; 50; 75 and 100 Gy. Seed germination and harvest of number of seeds and total production were assessed to identify occurrence of stimulation. Soya seeds and plants were handled as for usual seed production in Brazil. The low doses of gamma radiation in the seeds that stimulate the production were doses of 25, 50 and 75 Gy. There are evidences that the use of low doses of gamma radiation can stimulate germination and plant production. (author)

  12. Different gamma radiation doses effects of 60 Co on buds of banana plant (Nanicao-AAA) breeded in vitro

    International Nuclear Information System (INIS)

    Alves, Gilberto Dias; Colaco, Waldeciro

    1999-01-01

    Buds from banana cv. Nanicao-AAA (3 mm x 3 mm) were aseptically cultured in a modified Murashige and Skoog (MS) basal medium supplement with bezylaminepurine and sucrose, and solidified with agar. Buds placed on sterile Petri dishes were irradiated with increasing gamma rays doses (10, 20, 30, and 40 Gy). The statistical design was completely randomized with 5 doses and 30 replications. After irradiation, buds were transferred to 10 ml of the same medium into test tubes, and allowed to grow in a controlled environment (25 deg C, 16 h illumination ) for 4 weeks. There were no significant differences (Tukey, 0,05) between doses in terms of oxidation: in around 20% for all treatments. On the other hand, a statistically significant decrease in the germination of new buds with increased doses of irradiation was observed. The treatment with 40 Gy reduced in 80% the germination of new buds by the end of the evaluated period (4 weeks), resulting in a mean production of 1,5 buds. Mean production in the control was 7,6 buds. no statistically significant differences were detected between treatments with 10, 20, and 30 Gy, with a mean production of 3 buds, less than half obtained in the control. (author)

  13. Gamma-radiation induced synthesis of silver nanoparticles in gelatin and its application for radiotherapy dose measurements

    Science.gov (United States)

    Soliman, Y. S.

    2014-09-01

    A new gel dosimeter based on a radiation-sensitive silver nitrate was formulated and investigated for its potential use in γ-radiation treatment, from 3 to 100 Gy. This gel matrix is analyzed by UV-vis spectrophotometry and X-ray diffraction (XRD). Subjecting the gel to γ-rays produces Ag nanoparticles that exhibit a plasmon resonance absorption band at 450 nm. The intensity of this band increases linearly with the increase of absorbed dose up to 100 Gy. Stability of Ag nanoparticle in the dark at 6 °C is good. The overall uncertainty (2σ) of the gel dosimeter is estimated as ~4.65% in the dose range of 5-100 Gy.

  14. EPR response of sucrose and microcrystalline cellulose to measure high doses of gamma radiation; Respuesta EPR de sacarosa y celulosa micro cristalina para medir altas dosis de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Torijano, E.; Cruz, L.; Gutierrez, G.; Azorin, J.; Aguirre, F. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico); Cruz Z, E., E-mail: eftc@xanum.uam.mx [UNAM, Instituto de Ciencias Nucleares, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2015-10-15

    Solid dosimeters of sucrose and microcrystalline cellulose (Avicel Ph-102) were prepared, following the same process, in order to compare their EPR response against that of the l-alanine dosimeters considered as reference. All lots of dosimeters were irradiated with gamma radiation in Gamma beam irradiator with 8 kGy/h of the Nuclear Sciences Institute of UNAM. Doses ranged from 1 to 10 kGy respectively. We found that both the response of sucrose as microcrystalline cellulose were linear; however, the response intensity was, on average, twenty times more for sucrose. Comparing this against the EPR response of l-alanine in the range of doses, it was found that the response to sucrose is a third part; and microcrystalline cellulose is a sixtieth, approximately. The results agree with those found in the literature for sucrose, leaving open the possibility of investigating other dosage ranges for cellulose. (Author)

  15. Cotton Leaf worm: Inherited Effects of Low Doses of Gamma Radiation on The Progeny of Irradiated Males. Vol. 4

    Energy Technology Data Exchange (ETDEWEB)

    Sallam, H A; El-Naggar, S M; Shible, M M [Plant Protection Department, Faculty of Agriculture, Al-Azhar University, Cairo, (Egypt); El-Dessouki, S A; El-Awady, S M [Biological Applications Department, Nuclear Research Center, Atomic Energy Authority, Cairo, (Egypt)

    1996-03-01

    Full grown male pupae of the cotton leaf worm, Spodoptera Littoralis (Boisd.) were gamma irradiated with low doses of 25, 50,75, and 100 Gy. The effects on reproduction, development and sex ratio were the biological aspects studied among P{sub 1}, F{sub 1}, F{sub 2}, F{sub 3} generations. Fecundity of normal females mated with F{sub 1} or F{sub 2} males was significantly reduced for all doses. The F{sub 1} males were more sterile than their irradiated parental males, while F{sub 2} males were more fertile F{sub 1} males. Irradiation of P{sub 1} males did not clearly affect neither the percentage of mated females nor the average number of spermatophores per mated females among the individuals of P{sub 1}, F{sub 1}, F{sub 2}, F{sub 3} generations. The percent of larvae surviving to the adult stage was gradually decreased by increasing dose to P{sub 1} male throughout the first three filial generation. The average larval and pupal durations were not affected among the progeny of P{sub 1} males for both males and females. The sex ratio among the progeny of irradiated males was nearly 1:1. 3 tabs.

  16. Cotton Leaf worm: Inherited Effects of Low Doses of Gamma Radiation on The Progeny of Irradiated Males. Vol. 4

    International Nuclear Information System (INIS)

    Sallam, H.A.; El-Naggar, S.M.; Shible, M.M.; El-Dessouki, S.A.; El-Awady, S.M.

    1996-01-01

    Full grown male pupae of the cotton leaf worm, Spodoptera Littoralis (Boisd.) were gamma irradiated with low doses of 25, 50,75, and 100 Gy. The effects on reproduction, development and sex ratio were the biological aspects studied among P 1 , F 1 , F 2 , F 3 generations. Fecundity of normal females mated with F 1 or F 2 males was significantly reduced for all doses. The F 1 males were more sterile than their irradiated parental males, while F 2 males were more fertile F 1 males. Irradiation of P 1 males did not clearly affect neither the percentage of mated females nor the average number of spermatophores per mated females among the individuals of P 1 , F 1 , F 2 , F 3 generations. The percent of larvae surviving to the adult stage was gradually decreased by increasing dose to P 1 male throughout the first three filial generation. The average larval and pupal durations were not affected among the progeny of P 1 males for both males and females. The sex ratio among the progeny of irradiated males was nearly 1:1. 3 tabs

  17. Response of human lymphocytes to low gamma ray doses

    International Nuclear Information System (INIS)

    Vega Carrillo, HR; Banuelos Valenzuela, R; Manzanares Acuna, E; Sanchez-Rodriguez, S.H

    2001-01-01

    Radiation and non-radiation workers lymphocytes were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp25, Hsp60, Hsp70 and Hsp90; from these, only Hsp70 protein was detected before and after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 70.5 mGy gamma-ray dose, radiation worker's lymphocytes expressed more Hsp70 protein, than non-radiation workers' lymphocytes, indicating a larger tolerance to gamma rays (gamma tolerance), due to an adaptation process developed by their labor condition (Au)

  18. High dose gamma-ray standard

    International Nuclear Information System (INIS)

    Macrin, R.; Moraru, R.

    1999-01-01

    The high gamma-ray doses produced in a gamma irradiator are used, mainly, for radiation processing, i.e. sterilization of medical products, processing of food, modifications of polymers, irradiation of electronic devices, a.s.o. The used absorbed doses depend on the application and cover the range 10 Gy to 100 MGy. The regulations in our country require that the response of the dosimetry systems, used for the irradiation of food and medical products, be calibrated and traceable to the national standards. In order to be sure that the products receive the desired absorbed dose, appropriate dosimetric measurements must be performed, including the calibration of the dosemeters and their traceability to the national standards. The high dose gamma-ray measurements are predominantly based on the use of reference radiochemical dosemeters. Among them the ferrous sulfate can be used as reference dosemeter for low doses (up to 400 Gy) but due to its characteristics it deserves to be considered a standard dosemeter and to be used for transferring the conventional absorbed dose to other chemical dosemeters used for absorbed doses up to 100 MGy. The study of the ferrous sulfate dosemeter consisted in preparing many batches of solution by different operators in quality assurance conditions and in determining for all batches the linearity, the relative intrinsic error, the repeatability and the reproducibility. The principal results are the following: the linear regression coefficient: 0.999, the relative intrinsic error: max.6 %, the repeatability (for P* = 95 %): max.3 %, the reproducibility (P* = 95%): max.5 %. (authors)

  19. Calculation of Water Levels in Spent Fuel Pool and Effective Dose Followed by the Worker Geometrically Exposed to Radiation using Gamma-ray Source

    International Nuclear Information System (INIS)

    Lee, Donghee; Park, Kwangheon; Yoon, Hyoungju

    2013-01-01

    If the total effective dose value is lower than the surface dose rate of the water, the worker is able to work in a safe environment. In the case that the level of spent fuel pool is up to 550cm, there exists the limitation for workers to access to the storage pool because the result value is about 8 times higher than surface dose rate. In the case that the level of spent fuel pool is higher than 600cm, however, it can be safe work environment because the result value is lower than surface dose rate. Therefore, in the case of ISO geometry which is the same with practical situation, when considering Gamma-ray emission from spent fuel, effective dose is much higher than surface dose rate when the level of storage pool is lower than the height of fuel, 452.8cm. On the other hand, the level of effective dose decreases rapidly when the level of storage pool is higher than the level of the fuel. This means that it is not the safe environment when the level of fuel below 140cm is lower than surface dose rate. That is why the access of workers should be limited. Whereas, in the case of the level of storage pool above 600cm which is about 140cm higher than the level of the fuel, it is the safe environment for workers because the result value becomes lower than surface dose rate As a result, the level of wet storage of spent fuel should be at least 600cm for workers to work in safe environment because lower dose than surface dose rate makes less radiation exposure

  20. Effect of low doses gamma radiation on the yield of tomato (local variety) grown in the open field (1990 and 1992)

    International Nuclear Information System (INIS)

    Al-Oudat, M.; Ayyoubi, Z.

    1994-04-01

    The stimulating effects of low doses of ionizing radiation on growth of various plants has been reported by many investigators. In 1970, the FAO/IAEA consultant group strongly recommended tomato as a test plant due to its economic importance and good adaptability to many climatic conditions. This work was carried out during the summer seasons of 1990 and 1992 in two sites in Damascus region. Samples of air dried seeds of tomato (Local variety) of previous season were irradiated by gamma-rays from a 137 Cs source using doses of 5, 10, 12.5, 15, 20, 30 and 40 Gy at dose rate of 9 Gy/min. Seeds were sown after 2 days from irradiation in complete randomized block design and replicated 4 times. The data revealed that gamma irradiation at interval doses of 5-12.5 Gy (in Khan-El-Sheeh) and 10-30 Gy (in Deir-El-Hajar) have stimulating effects on number of branches and early yield. The results of total yield as well as fruits number were significantly increased when doses of 10 and 12.5 Gy in Khan-El-Sheeh and 12.5-25 Gy in Deir-El-Hajar, were used. The percentage of increment varied from 12.6 to 18.2% in Khan-El-Sheeh and 14.3 to 30.9% in Deir-El-Hajar. In view of all above mentioned results, the use of radiation might be recommended as an easy tool for seed treatments to stimulate and increase the productivity of tomato. (author). 12 tabs

  1. Effect of the gamma radiation dose rate on psychrotrophic bacteria, thiobarbituric acid reactive substances, and sensory characteristics of mechanically deboned chicken meat.

    Science.gov (United States)

    Brito, Poliana P; Azevedo, Heliana; Cipolli, Kátia M V A B; Fukuma, Henrique T; Mourão, Gerson B; Roque, Cláudio V; Miya, Norma T; Pereira, José L

    2011-03-01

    Frozen samples of mechanically deboned chicken meat (MDCM) with skin were irradiated with gamma radiation doses of 0.0 kGy (control) and 3 kGy at 2 different radiation dose rates: 0.32 kGy/h (3 kGy) and 4.04 kGy/h (3 kGy). Batches of irradiated and control samples were evaluated during 11 d of refrigerated (2 ± 1 °C) storage for the following parameters: total psychrotrophic bacteria count, thiobarbituric acid reactive substances (TBARS), evaluation of objective color (L*, a*, and b*) and a sensory evaluation (irradiated odor, oxidized odor, pink and brown colors). No statistical difference (P > 0.05) was found amongst the TBARS values obtained for the MDCM samples irradiated with dose rates of 0.32 and 4.04 kGy/h. There was a significant increase (P radiation to mechanically deboned chicken meat will provide the food industry with information concerning the definition of the best processing conditions to maximize the sensory and food quality.

  2. A New Approach for the Determination of Dose Rate and Radioactivity for Detected Gamma Nuclides Using an Environmental Radiation Monitor Based on an NaI(Tl) Detector.

    Science.gov (United States)

    Ji, Young-Yong; Kim, Chang-Jong; Lim, Kyo-Sun; Lee, Wanno; Chang, Hyon-Sock; Chung, Kun Ho

    2017-10-01

    To expand the application of dose rate spectroscopy to the environment, the method using an environmental radiation monitor (ERM) based on a 3' × 3' NaI(Tl) detector was used to perform real-time monitoring of the dose rate and radioactivity for detected gamma nuclides in the ground around an ERM. Full-energy absorption peaks in the energy spectrum for dose rate were first identified to calculate the individual dose rates of Bi, Ac, Tl, and K distributed in the ground through interference correction because of the finite energy resolution of the NaI(Tl) detector used in an ERM. The radioactivity of the four natural radionuclides was then calculated from the in situ calibration factor-that is, the dose rate per unit curie-of the used ERM for the geometry of the ground in infinite half-space, which was theoretically estimated by Monte Carlo simulation. By an intercomparison using a portable HPGe and samples taken from the ground around an ERM, this method to calculate the dose rate and radioactivity of four nuclides using an ERM was experimentally verified and finally applied to remotely monitor them in real-time in the area in which the ERM had been installed.

  3. Environmental gamma radiation measurements in Bangladeshi houses

    International Nuclear Information System (INIS)

    Idrish Miah, M.

    2002-01-01

    The indoor gamma dose rate in air measured using TLDs in the Dhaka district is not wide ranging and follows a normal distribution with an arithmetic mean of 1.54±0.26 mGy.y -1 . The result has been compared with those found by other investigators for different locations of the world. Measurements were made on a monthly basis for a year period, and a sinusoidal variation of monthly indoor gamma radiation of the type: d = 160 + 65 cos p/6 (m -1 ), where d is the indoor dose rate (nGy.h -1 ) and m the month, was observed. This might be due to seasonally varied air exchange rates of the houses. The average annual effective dose and the collective dose equivalent for the residents were estimated to be 0.86 mSv and 172.20 man-Sv respectively based on the indoor gamma exposure. (author)

  4. Environmental gamma radiation measurements in Bangladeshi houses

    International Nuclear Information System (INIS)

    Miah, M.I.

    2004-01-01

    Indoor gamma dose rate in air measured using TLDs in the Dhaka district is not wide ranging and follows a normal distribution with an arithmetic mean of 1.54±0.26 mGy y -1 . The result has been compared with those found by other investigators for different locations of the world. Measurements were made on a monthly basis for a year period, and a sinusoidal variation of monthly indoor gamma radiation of the type: d=160+65 cos π/6 (m-1), where d is the indoor dose rate (nGy h -1 ) and m the month. This might be due to the seasonally varied air exchange rates of the houses. The average annual effective dose and the collective dose equivalent for the residents were estimated to be 0.86 mSv and 172.20 man-Sv, respectively, based on the indoor gamma exposure

  5. Environmental gamma radiation measurements in Bangladeshi houses

    Energy Technology Data Exchange (ETDEWEB)

    Miah, M.I. E-mail: idrish_physics@yahoo.com

    2004-06-01

    Indoor gamma dose rate in air measured using TLDs in the Dhaka district is not wide ranging and follows a normal distribution with an arithmetic mean of 1.54{+-}0.26 mGy y{sup -1}. The result has been compared with those found by other investigators for different locations of the world. Measurements were made on a monthly basis for a year period, and a sinusoidal variation of monthly indoor gamma radiation of the type: d=160+65 cos {pi}/6 (m-1), where d is the indoor dose rate (nGy h{sup -1}) and m the month. This might be due to the seasonally varied air exchange rates of the houses. The average annual effective dose and the collective dose equivalent for the residents were estimated to be 0.86 mSv and 172.20 man-Sv, respectively, based on the indoor gamma exposure.

  6. Low Dose Radiation Response Curves, Networks and Pathways in Human Lymphoblastoid Cells Exposed from 1 to 10 cGy of Acute Gamma Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Wyrobek, A. J.; Manohar, C. F.; Nelson, D. O.; Furtado, M. R.; Bhattacharya, M. S.; Marchetti, F.; Coleman, M.A.

    2011-04-18

    We investigated the low dose dependency of the transcriptional response of human cells to characterize the shape and biological functions associated with the dose response curve and to identify common and conserved functions of low dose expressed genes across cells and tissues. Human lymphoblastoid (HL) cells from two unrelated individuals were exposed to graded doses of radiation spanning the range of 1-10 cGy were analyzed by transcriptome profiling, qPCR and bioinformatics, in comparison to sham irradiated samples. A set of {approx}80 genes showed consistent responses in both cell lines; these genes were associated with homeostasis mechanisms (e.g., membrane signaling, molecule transport), subcellular locations (e.g., Golgi, and endoplasmic reticulum), and involved diverse signal transduction pathways. The majority of radiation-modulated genes had plateau-like responses across 1-10 cGy, some with suggestive evidence that transcription was modulated at doses below 1 cGy. MYC, FOS and TP53 were the major network nodes of the low-dose response in HL cells. Comparison our low dose expression findings in HL cells with those of prior studies in mouse brain after whole body exposure, in human keratinocyte cultures, and in endothelial cells cultures, indicates that certain components of the low dose radiation response are broadly conserved across cell types and tissues, independent of proliferation status.

  7. Gamma radiation utilization for polymers synthesis

    International Nuclear Information System (INIS)

    Santos, L.G. dos; Silva Filho, E.

    1990-01-01

    Samples of styrene monomer were irradiated with gamma rays from a sup(60)Co source, with doses in the range of zero to 32600 Gray (Gy). Viscosity analysis performed by using the method of Stokes showed an increase in the viscosity of the material. This result characterizes the occurrence of polymerization induced by the radiation. (author)

  8. Gamma radiation sterilization of Bactrocera invadens (Diptera ...

    African Journals Online (AJOL)

    The African invader fly, Bactrocera invadens, an invasive pest in Africa since 2003, causes damage and poses a threat to the mango and horticultural industry. Its control is therefore needed. Sterilization of males using gamma radiation doses (25, 50 and 75 Gy) as a means of population control was investigated. Irradiation ...

  9. Gamma and electron radiation effects on straw

    International Nuclear Information System (INIS)

    Leonhardt, J.W.; Baer, M.; Huebner, G.

    1983-01-01

    Gamma and electron radiation effects on wheat straw, oat straw, barley straw and rye straw are reported. In vitro and in vivo studies show that the digestibility of these agricultural rough materials can be increased up to 80% and more at high doses. The increase of the digestibility is connected with a depolymerisation of cellulose and hemicellulose. (author)

  10. Determination of gamma radiation dose to the destruction of Escherichia coli O157: H7 in hamburger

    International Nuclear Information System (INIS)

    Orejuela Chirinos, Rodolfo Raul

    1999-01-01

    Escherichia coli O157:H7 has been incriminated in several foodborne outbreaks due to the consumption of different kinds of foods. Among these, hamburgers are the most common. Irradiation process is an effective method for food preservation because it causes no significant change in organoleptic and nutritional food characteristics and destroys pathogens and spoilage microorganisms. Hamburgers and nutrient broth inoculated with Escherichia coli O157:H7 were submitted to gamma irradiation ( 60 Co) treatment, with doses ranging from 0,0 to 0,7 kGy in order to calculate the D 10 for this bacteria in these substrate. The D 10 for the pathogen nutrient broth ranged from 0.08 kGy to 0.10 kGy and in hamburger from 0.11 kGy to 0.21 kGy. Considering the highest D 10 value in hamburger, a dose of 0,8 kGy would not change the sensorial characteristics of the product, and would reduce the population of E. coli O157:H7 in 4 cycles logarithmic. (author)

  11. Behavior of pea saber plants (Canavalia ensiformis (L) DC)) ontenus from seeds exposed to increasing doses of gamma radiation

    International Nuclear Information System (INIS)

    Kalonji, M.A.; Mudibu wa Kabangu, J.; Tshilenge-Djim, P.; Tshivuila, T.D.; Gaza, O.C.

    2003-01-01

    The present trial has carried out in order to determine the optimal value of usable treatment for seeds exposed to the gamma radiances. Seeds of Canavalia ensiformis presenting a rate of humidity of 15% have been submitted to the increasing doses of irradiation (source Cesium 137) of 10, 20, 30, 40 and 50 Krads. After germination, plants generated from these seeds have been observed in a completely randomized blocks experimental design, including six treatments and three repetitions. Observations concerned the vegetative parameters (germination percent, height, diameter to the collar, number of ramification, surface of leaves), the generative parameters (number of pod by plant, length and width of pods, number of seeds by pod, weights of 100 seeds) and the morphological changes on distortions of plants during their vegetative development. Results permitted to determine that the optimal value of treatment is located to 10 Krads. This dose induced a high rate of seed germination, vigorous plants with a high number of ramifications. The yield parameters obtained with 10 and 20 Krads, excepted the weight of 100 seeds, have been lower than to those obtained with the control. This is the consequence of the increase of the pod dimension and the size of seeds. All treatments superior to 30 Krads have been lethal. Materials treated to 10 and 20 Krads are under observation for the second generation.

  12. Effects of film thickness on scintillation characteristics of columnar CsI:Tl films exposed to high gamma radiation doses

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, Seema; Singh, S.G.; Sen, S.; Gadkari, S.C., E-mail: gadkari@barc.gov.in

    2016-02-21

    Oriented columnar films of Tl doped CsI (CsI:Tl) of varying thicknesses from 50 µm to 1000 µm have been deposited on silica glass substrates by a thermal evaporation technique. The SEM micrographs confirmed the columnar structure of the film while the powder X-ray diffraction pattern recorded for the films revealed a preferred orientation of the grown columns along the <200> direction. Effects of high energy gamma exposure up to 1000 Gy on luminescence properties of the films were investigated. Results of radio-luminescence, photo-luminescence and scintillation studies on the films are compared with those of a CsI:Tl single crystal with similar thickness. A possible correlation between the film thicknesses and radiation damage in films has been observed. - Highlights: • CsI:Tl films of different thicknesses deposited for γ and α detection. • Pulse-height spectra found to degrade with increasing thickness. • Radiation damage is found more in films than single crystal of comparable thickness. • Detection efficiency increases for γ while it is invariant for α beyond 50 µm.

  13. Effects of film thickness on scintillation characteristics of columnar CsI:Tl films exposed to high gamma radiation doses

    International Nuclear Information System (INIS)

    Shinde, Seema; Singh, S.G.; Sen, S.; Gadkari, S.C.

    2016-01-01

    Oriented columnar films of Tl doped CsI (CsI:Tl) of varying thicknesses from 50 µm to 1000 µm have been deposited on silica glass substrates by a thermal evaporation technique. The SEM micrographs confirmed the columnar structure of the film while the powder X-ray diffraction pattern recorded for the films revealed a preferred orientation of the grown columns along the direction. Effects of high energy gamma exposure up to 1000 Gy on luminescence properties of the films were investigated. Results of radio-luminescence, photo-luminescence and scintillation studies on the films are compared with those of a CsI:Tl single crystal with similar thickness. A possible correlation between the film thicknesses and radiation damage in films has been observed. - Highlights: • CsI:Tl films of different thicknesses deposited for γ and α detection. • Pulse-height spectra found to degrade with increasing thickness. • Radiation damage is found more in films than single crystal of comparable thickness. • Detection efficiency increases for γ while it is invariant for α beyond 50 µm.

  14. Terrestrial gamma dose rate, radioactivity and radiological hazards in the rocks of an elevated radiation background in Juban District, Ad Dali' Governorate, Yemen.

    Science.gov (United States)

    Abdurabu, Wedad Ali; Ramli, Ahmad Termizi; Saleh, Muneer Aziz; Heryansyah, Arien; Alnhary, Anees; Fadhl, Shadi

    2016-03-01

    This study aims to evaluate natural radiation and radioactivity in the rock and to assess the corresponding health risk in a region of elevated background radiation in Juban District, Ad Dali' Governorate, Yemen. The mean external gamma dose rate was 374 nGy h(-1) which is approximately six times the world average. The measured results were used to compute annual effective dose equivalent, collective effective dose and excess lifetime cancer risk, which are 2.298 mSv, 61.95 man Sv y(-1) and 8.043  ×  10(-3), respectively. Rocks samples from different geological formations were analyzed for quantitative determination of (226)Ra, (232)Th and (40)K. The specific activity of the rocks samples ranges from 7  ±  1 Bq Kg(-1) to 12 513  ±  329 Bq Kg(-1) for (232)Th, from 6  ±  1 Bq kg(-1) to 3089  ±  74 Bq kg(-1) for (226)Ra and 702  ±  69 Bq kg(-1) to 2954  ±  285 Bq kg(-1) for (40)K. (232)Th is the main contributor to gamma dose rate from the rock samples. Indicators of radiological health impact, radium equivalent activity and external hazard index are 3738 Bq kg(-1) and 10.10, respectively. The mean external hazard index was ten times unity in the studied locations in Juban District, which is higher than the recommended value.

  15. SU-E-T-517: Investigation of Factors Contributing to Extracranial Radiation Doses From Leksell Gamma Knife

    Energy Technology Data Exchange (ETDEWEB)

    Kon, D [The University of Tokyo Graduate school of Medicine, Tokyo, JP (Japan); Kameda Medical Centre, Chiba, JP (Japan); Nakano, M [The University of Tokyo Graduate school of Medicine, Tokyo, JP (Japan); Nawa, K; Haga, A; Nakagawa, K [University of Tokyo Hospital, Tokyo, JP (Japan)

    2015-06-15

    Purpose The purpose of this study is to investigate dominant factors for doses to extracranial sites in treatment with Leksell Gamma Knife (LGK). Methods Monte Carlo simulation was implemented using EGS5 version 1.4.401. The simulation was divided into two major steps for the purpose of efficiency. As the first step, phase-space files were obtained at a scoring plane located just below patient-side surface of the collimator helmet of LGK. Scored particles were classified into three groups, primary, leakage and scatter, using their history information until their arrival to the scoring plane. Then classification was used at the following second step simulation to investigate which type of particle is dominant in the deposited energy at extra-cranial sites. In the second stage, a cylindrical phantom with a semisphere shaped head was modeled such that the geometrical center of the phantom’s head corresponds to the unit center point (UCP) of LGK. Scoring regions were arranged at 10 cm intervals from the UCP to 70 cm away on the central axis of the phantom. Energy deposition from each type of particles and location of interaction were recorded. Results The dominant factor of deposited energy depended on the collimator size. In the case of smaller collimator size, leakage was dominant. However, contribution of leakage was relatively small in the case of larger collimator size. The contribution of internal scatter varied with the distance from the UCP. In the proximal areas, internal scatter was dominant, whereas in the distal areas, particles interacting with machine components became dominant factor. Conclusion The Result of this study indicates that the dominant factor to dose to an extracranial site can vary with the distance from UCP and with collimator size. This means that the variation of this contribution must be considered for modeling of the extracranial dose especially in the distal area. This work was partly supported by the JSPS Core-to-Core Program (No

  16. Radiation dose in vertebroplasty

    International Nuclear Information System (INIS)

    Mehdizade, A.; Lovblad, K.O.; Wilhelm, K.E.; Somon, T.; Wetzel, S.G.; Kelekis, A.D.; Yilmaz, H.; Abdo, G.; Martin, J.B.; Viera, J.M.; Ruefenacht, D.A.

    2004-01-01

    We wished to measure the absorbed radiation dose during fluoroscopically controlled vertebroplasty and to assess the possibility of deterministic radiation effects to the operator. The dose was measured in 11 consecutive procedures using thermoluminescent ring dosimeters on the hand of the operator and electronic dosimeters inside and outside of the operator's lead apron. We found doses of 0.022-3.256 mGy outside and 0.01-0.47 mGy inside the lead apron. Doses on the hand were higher, 0.5-8.5 mGy. This preliminary study indicates greater exposure to the operator's hands than expected from traditional apron measurements. (orig.)

  17. Intercomparison exercise on external gamma dose rate under field conditions at the laboratory of natural radiation (Saelices el Chico, Spain)

    International Nuclear Information System (INIS)

    Gutierrez-Villanueva, J. L.; Sainz-Fernandez, C.; Fuente-Merino, I.; Saez-Vergara, J. C.; Correa-Garce, E.; Quindos-Poncela, L. S.

    2013-01-01

    The last nuclear accident in Fukushima nuclear power plant has increased the necessity for measuring radiation in the environment. Therefore, radiation monitors providing results traceable throughout the country become essential and it is very important to test them under the same environmental conditions. The first intercomparison of natural radioactivity under field conditions was held in Saelices el Chico (Salamanca, Spain) in May 2011, including an exercise on environmental dose rate. This article presents the results achieved by 19 instruments belonging to 12 institutions from 7 different countries. The tested detectors are proportional counters, ionisation chambers, Geiger-Mueller and scintillators measuring dose rate in three stations with reference values from 110 to 1800 nGy h -1 All the results were given in terms of air kerma (nGy h -1 ) and the measurements show agreement within 25 % in all the sites. Evaluation criteria based on accuracy and statistical uncertainty were also carried out and 25 % of participants passed the test in all sites. (authors)

  18. Residual water treatment for gamma radiation

    International Nuclear Information System (INIS)

    Mendez, L.

    1990-01-01

    The treatment of residual water by means of gamma radiation for its use in agricultural irrigation is evaluated. Measurements of physical, chemical, biological and microbiological contamination indicators were performed. For that, samples from the treatment center of residual water of San Juan de Miraflores were irradiated up to a 52.5 kGy dose. The study concludes that gamma radiation is effective to remove parasites and bacteria, but not for removal of the organic and inorganic matter. (author). 15 refs., 3 tabs., 4 figs

  19. Sensitiveness of jasmine cuttings to gamma radiation

    International Nuclear Information System (INIS)

    Devaiah, K.A.; Srivastava, H.C.

    1989-01-01

    Half lethal dose (LD 50 ) gamma radiation for five genotypes of jasmine and the effect of such radiation on their rooting parameters were studied. The LD 50 was close to 2.5 krad for Jasminum grandiflorum var. Pink Pin, 0.5 krad for var. Pink Thrum, 2.5 krad for J. flexile Valh., 1 krad for J. calophyllum Wall and 2 krad for J. sambac Ait var. 'Gundumalli'. Percentage of rooting, number of roots per cutting, length and thickness of roots decreased with increase in intensity of gamma irradiation. (author) 8 refs.; 4 tabs

  20. A comparison of Australian and Canadian calibration coefficients for air kerma and absorbed dose to water for 60Co gamma radiation.

    Science.gov (United States)

    Shortt, K R; Huntley, R B; Kotler, L H; Boas, J F; Webb, D V

    2006-06-01

    Australian and Canadian calibration coefficients for air kerma and absorbed dose to water for 60Co gamma radiation have been compared using transfer standard ionization chambers of types NE 2561 and NE 2611A. Whilst the primary standards of air kerma are similar, both being thick-walled graphite cavity chambers but employing different methods to evaluate the Awall correction, the primary standards of absorbed dose to water are quite different. The Australian standard is based on measurements made with a graphite calorimeter, whereas the Canadian standard uses a sealed water calorimeter. The comparison result, expressed as a ratio of calibration coefficients R=N(ARPANSA)/N(NRC), is 1.0006 with a combined standard uncertainty of 0.35% for the air kerma standards and 1.0052 with a combined standard uncertainty of 0.47% for the absorbed dose to water standards. This demonstrates the agreement of the Australian and Canadian radiation dosimetry standards. The results are also consistent with independent comparisons of each laboratory with the BIPM reference standards. A 'trilateral' analysis confirms the present determination of the relationship between the standards, within the 0.09% random component of the combined standard uncertainty for the three comparisons.

  1. Quantification of micronuclei in blood lymphocytes of patients exposed to gamma radiation for dose absorbed assessment; Quantificacao de micronucleos em linfocitos de pacientes expostas a radiacao gama para a avaliacao da dose absorvida

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Isvania Maria Serafim da Silva

    2003-02-15

    Dose assessment in an important step to evaluate biological effects as a result of individual exposure to ionizing radiation. The use of cytogenetic dosimetry based on the quantification of micronuclei in lymphocytes is very important to complement physical dosimetry, since the measurement of absorbed dose cannot be always performed. In this research, the quantification of micronuclei was carried out in order to evaluate absorbed dose as a result of radiotherapy with {sup 60}Co, using peripheral blood samples from 5 patients with cervical uterine cancer. For this purpose, an aliquot of whole blood from the individual patients was added in culture medium RPMI 1640 supplemented with fetal calf serum and phytohaemagglutinin. The culture was incubated for 44 hours. Henceforth, cytochalasin B was added to block the dividing lymphocytes in cytokinesis. The culture was returned to the incubator for further of 28 hours. Thus, cells were harvested, processed and analyzed. Values obtained considering micronuclei frequency after pelvis irradiation with absorption of 0,08 Gy and 1,8 Gy were, respectively, 0,0021 and 0,052. These results are in agreement with some recent researches that provided some standard values related to micronuclei frequency induced by gamma radiation exposure in different exposed areas for the human body. The results presented in this report emphasizes biological dosimetry as an important tool for dose assessment of either total or partial-body exposure to ionizing radiation, mainly in retrospective dose investigation. (author)

  2. Effect of gamma radiation on polyvinylpyrrolidone hydrogels

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, M.J.A.; Vásquez, P.A.S.; Alcântara, M.T.S.; Munhoz, M.M.L.; Lugão, A.B., E-mail: mariajhho@yahoo.com.br, E-mail: pavsalva@ipen.br, E-mail: ablugao@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    Polyvinylpyrrolidone (PVP) hydrogels have been investigated as drug delivery matrices for the treatment of wounds, such as cutaneous leishmaniasis, and matrices with silver nanoparticles for chronic wounds and burns. The preparation of such hydrogels can occur by various cross-linking methods, such as gamma, chemical, physical, among others. The most feasible for wound dressings is gamma irradiation from cobalt-60, because gamma irradiation simultaneously promotes crosslinking and sterilization, leaving the wound dressing ready for use. The objective of this work was to investigate the effect on physico- chemical properties of gamma radiation on PVP hydrogel according to the radiation absorbed dose variation. The PVP hydrogels were irradiated with doses of 5, 15, 25, 35, 45, 55, 65, 75 and 95kGy at dose rate of 5 kGy/h and characterized by swelling, thermogravimetric and mechanical analysis. Results shown a favorable dose range window for processing of these hydrogels related to the application. The results showed that mechanical strength was affected at doses starting at 25 kGy. (author)

  3. Effect of gamma radiation on polyvinylpyrrolidone hydrogels

    International Nuclear Information System (INIS)

    Oliveira, M.J.A.; Vásquez, P.A.S.; Alcântara, M.T.S.; Munhoz, M.M.L.; Lugão, A.B.

    2017-01-01

    Polyvinylpyrrolidone (PVP) hydrogels have been investigated as drug delivery matrices for the treatment of wounds, such as cutaneous leishmaniasis, and matrices with silver nanoparticles for chronic wounds and burns. The preparation of such hydrogels can occur by various cross-linking methods, such as gamma, chemical, physical, among others. The most feasible for wound dressings is gamma irradiation from cobalt-60, because gamma irradiation simultaneously promotes crosslinking and sterilization, leaving the wound dressing ready for use. The objective of this work was to investigate the effect on physico- chemical properties of gamma radiation on PVP hydrogel according to the radiation absorbed dose variation. The PVP hydrogels were irradiated with doses of 5, 15, 25, 35, 45, 55, 65, 75 and 95kGy at dose rate of 5 kGy/h and characterized by swelling, thermogravimetric and mechanical analysis. Results shown a favorable dose range window for processing of these hydrogels related to the application. The results showed that mechanical strength was affected at doses starting at 25 kGy. (author)

  4. Effect of low doses of gamma radiation of Co-60 (radio-hormesis) in tomato seeds; Efeitos de baixas doses de radiacao gama do Co-60 (radio-hormesis) em sementes de tomate

    Energy Technology Data Exchange (ETDEWEB)

    Wiendl, Toni Andreas

    2010-07-01

    Tomato seeds of the Gladiador hybrid were exposed to gamma radiation of Co-60 with the following doses: 0; 2,5; 5; 7,5; 10; 12,5; 15 e 20 Gy. Analysis were performed on germination, seedlings height to cotyledon, seedling total height, seedling fresh and dry weight, plant height, stalk diameter at the root beginning, fresh and dry weight of the 5{sup th} leaf, number of green fruits with diameter higher than 3 cm, number of green, half ripen and ripen fruits, total number of fruits, Brix and pH of fruits, average fruit weight and fruit total production. A variety of stimulation effects were observed on the different plant developing stages. The greatest stimulus for production was observed in the 10 Gy dose. The highest seedling average height and plant average height were observed for the 7,5 Gy dose. The biggest number of green fruits with diameter higher than 3 cm occurred for the 12,5 and 15 Gy treatments. Irradiation also stimulated a higher total number of fruits in all doses, having advantage the 10 Gy dose which produced 88% more fruits than control as well as 86% more weight production. The fruits pH acidified significantly in a dose of 12,5 Gy and higher. Production increased in all treatments comparing to control and the highest stimulus for production observed was for the 10, 12,5 and 15 Gy. The use of low gamma radiation doses of Co-60 applied as pre-sowing treatment in the seeds, efficiently stimulated the development of plants and the tomato production. (author)

  5. Low gamma radiation dose effect on germination and initial growing of black beans (Phaseolus vulgaris L.) seeds; Efeito de baixas doses de radiacao gama na germinacao de sementes de feijao (Phaseolus vulgaris L.)

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Edgar F.O. de; Silva, Anderson de O. Melo [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Lab. de Instrumentacao Nuclear]. E-mail: edgar@lin.ufrj.br; Marsico, Eliane T. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Faculdade de Veterinaria. Dept. de Tecnologia de Alimentos]. E-mail: elianee@vm.uff.br

    2005-07-01

    In this work we analyze the effect of low gamma irradiation doses and low concentrations of sodium alginate on the germination and growing of black beans seeds. The seeds were obtained from an organic farmer at Nova Friburgo, Rio de Janeiro State. The seeds were submitted to radiation doses between 0 and 150 Gy with a Cobalt 60 source in a Gammacell Excel 220 Nordion Irradiator with a dose rate of 70 Gy/min. After germination the seeds were left to grow three weeks on a hydroponics system. The system used was the water culture with nutritive solution that was supplemented with the nutritional needs for plant grows. We also tested the influence of the sodium alginate on the plant grows. A 4% solution of sodium alginate in distilled water was irradiated with 120 kGy gamma ray dose. Concentrations of sodium alginate irradiated and non-irradiated varying from 50 to 500 {mu}g/g were used in the hydroponics' solution. After three weeks the mass and the height of the plant were measured. Statistic analyses of he result with the SAS program show that there was no significant difference between the height and mass of seeds submitted different doses, but irradiated solution of sodium alginate with concentration of 400 and 500 {mu}g/g present a significant difference on plant grow. (author)

  6. Investigation of zones with increased ground surface gamma radiation

    International Nuclear Information System (INIS)

    Butkus, D.V.; Morkunas, G.S.; Styro, B.I.

    1989-01-01

    Measurements of the increased gamma radiation zones of soils were conducted in the South-Western part of the Litvinian. The shores of lakes in the north-eastern part of the Suduva high land were investigated. the maximum values of the gamma radiation dose rates were distributed along the lake shores at a distance of 1 m from the water surface, while farther than 1.5 m from it the dose rate was close to the natural value. The increased gamma radiation intensity zones on the ground surface were found only at the northern (Lake Reketija) or the western shore (other lakes under investigation). The highest values of the gamma radiation dose 200-600 μR/h (0.5-1.5 nGy/s) were observed in the comparatively small areas (up to several square metres). The gamma radiation intensity of soil surface increased strongly moving towards the point where the maximum intensity was obsered. 10 figs

  7. Standardization of high-dose measurement of electron and gamma ray absorbed doses and dose rates

    International Nuclear Information System (INIS)

    McLaughlin, W.L.

    1985-01-01

    Intense electron beams and gamma radiation fields are used for sterilizing medical devices, treating municipal wastes, processing industrial goods, controlling parasites and pathogens, and extending the shelf-life of foods. Quality control of such radiation processes depends largely on maintaining measurement quality assurance through sound dosimetry procedures in the research leading to each process, in the commissioning of that process, and in the routine dose monitoring practices. This affords documentation as to whether satisfactory dose uniformity is maintained throughout the product and throughout the process. Therefore, dosimetry at high doses and dose rates must in many radiation processes be standardized carefully, so that 'dosimetry release' of a product is verified. This standardization is initiated through preliminary dosimetry intercomparison studies such as those sponsored recently by the IAEA. This is followed by establishing periodic exercises in traceability to national or international standards of absorbed dose and dose rate. Traceability is achieved by careful selection of dosimetry methods and proven reference dosimeters capable of giving sufficiently accurate and precise 'transfer' dose assessments: (1) they must be calibrated or have well-established radiation-yield indices; (2) their radiation response characteristics must be reproducible and cover the dose range of interest; (3) they must withstand the rigours of back-and-forth mailing between a central standardizing laboratory and radiation processing facilities, without excessive errors arising due to instabilities, dosimeter batch non-uniformities, and environmental and handling stresses. (author)

  8. Dose assessment by quantification of chromosome aberrations and micronuclei in peripheral blood lymphocytes from patients exposed to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Silva-Barbosa, Isvania; Pereira-MagnataI, Simey; Amaral, Ademir [Pernambuco Univ., Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia - GERAR; Sotero, Graca [Fundacao de Hematologia e Hemoterapia, Recife, PE (Brazil); Melo, Homero Cavalcanti [Hospital do Cancer, Recife, PE (Brazil). Centro de Radioterapia de Pernambuco]. E-mail: isvania@uol.com.br

    2005-07-15

    Scoring of unstable chromosome aberrations (dicentrics, rings and fragments) and micronuclei in circulating lymphocytes are the most extensively studied biological means for estimating individual exposure to ionizing radiation (IR), which can be used as complementary methods to physical dosimetry or when the latter cannot be performed. In this work, the quantification of the frequencies of chromosome aberrations and micronuclei were carried out based on cytogenetic analyses of peripheral blood samples from 5 patients with cervical uterine cancer following radiotherapy in order to evaluate the absorbed dose as a result of partial-body exposure to 60Co source. Blood samples were collected from each patient in three phases of the treatment: before irradiation, 24 h after receiving 0.08 Gy and 1.8 Gy, respectively. The results presented in this report emphasize biological dosimetry, employing the quantification of chromosome aberrations and micronuclei in lymphocytes from peripheral blood, as an important methodology of dose assessment for either whole or partial-body exposure to IR.

  9. Effect of gamma radiation on optical and electrical properties of ...

    Indian Academy of Sciences (India)

    Wintec

    Tellurium dioxide; thin films; optical bandgap; gamma radiation dose; dosimeter. 1. Introduction. It is now ... material to ionizing radiations (such as X-rays, gamma rays, beta ..... Mag. 19 19. Mott N F and Davis E 1979 Electronic process in non-.

  10. Doses from radiation exposure

    International Nuclear Information System (INIS)

    Menzel, H-G.; Harrison, J.D.

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection’s (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP’s 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effective dose. In preparation for the calculation of new dose coefficients, Committee 2 and its task groups have provided updated nuclear decay data (ICRP Publication 107) and adult reference computational phantoms (ICRP Publication 110). New dose coefficients for external exposures of workers are complete (ICRP Publication 116), and work is in progress on a series of reports on internal dose coefficients to workers from inhaled and ingested radionuclides. Reference phantoms for children will also be provided and used in the calculation of dose coefficients for public exposures. Committee 2 also has task groups on exposures to radiation in space and on the use of effective dose.

  11. Induction of inherited sterility and sex ratio distribution due to exposure to substerilising doses of gamma radiation in cotton bollworm Earias vittella fabricius

    International Nuclear Information System (INIS)

    Tamhankar, A.J.; Shantharam, K.

    2005-01-01

    Substerilising doses of gamma radiation induced inherited sterility and sex ratio distortion in the cotton bollworm Earias vittella fabricius. Adults irradiated with 75 Gy and self-crossed, provided sterile F 1 adults, suitable for direct use in sterile insect technique (SIT). In case of 50 Gy, the F 1 adults, when backcrossed, produced F 2 progeny with sex ratio in favour of females (1: >3). With 25 Gy, a sex ratio distortion was recorded in F 1 (1 male: 2.25 females) and self-crossing of F 1 resulted in progeny with a sex ratio of 3:1. Backcrossing of the F 1 female produced F 2 progeny with a sex ratio of 1:5. These results have implications in improving cost/benefit ratio of SIT for this species. (author)

  12. The ferrous ammonium sulfate solid system, as dosemeter for processes at low temperatures and high doses of gamma radiation; El sistema sulfato ferroso amoniacal solido, como dosimetro para procesos a bajas temperaturas y altas dosis de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Juarez C, J.M.; Ramos B, S.; Negron M, A. [ICN-UNAM, 04510 Mexico D.F. (Mexico)

    2005-07-01

    This paper presents the results obtained from a study of the radiation induced oxidation of crystalline ferrous ammonium sulfate with gamma rays at 295 K, 263 K and 77 K and dose from 0 to 300 kGy. The radiation induced decomposition of ferrous ammonium sulfate has been studied by the dissolution of the irradiated salt in 0,8 N sulfuric acid. The main product is Fe{sup 3+} and molar concentration of ferric ion was determined spectrophotometrically in the UV region at 304 nm. The optical density values showed a linear dependence with dose, indicating that the data obtained might be used to create a calibrating curve. Color in irradiated salt changes from blue to green, yellow and orange according to the absorbed dose. The accuracy and the reproducibility of the system were tested. In addition, some other characteristics make possible the use of this system as a dosimeter, similar to Fricke chemical dosemeter, at low temperatures and high dose. (Author)

  13. Terrestrial gamma dose rate in Pahang state Malaysia

    International Nuclear Information System (INIS)

    Gabdo, H.T.; Federal College of Education, Yola; Ramli, A.T.; Sanusi, M.S.; Saleh, M.A.; Garba, N.N.; Ahmadu Bello University, Zaria

    2014-01-01

    Environmental terrestrial gamma radiations (TGR) were measured in Pahang state Malaysia between January and April 2013. The TGR dose rates ranged from 26 to 750 nGy h -1 . The measurements were done based on geology and soil types of the area. The mean TGR dose rate was found to be 176 ± 5 nGy h -1 . Few areas of relatively enhanced activity were located in Raub, Temerloh, Bentong and Rompin districts. These areas have external gamma dose rates of between 500 and 750 nGy h -1 . An Isodose map of the state was produced using ArcGIS9 software version 9.3. To evaluate the radiological hazard due to terrestrial gamma dose, the annual effective dose equivalent and the mean population weighted dose rate were calculated and found to be 0.22 mSv year -1 and 168 nGy h -1 respectively. (author)

  14. Cellular response to low Gamma-ray doses

    Energy Technology Data Exchange (ETDEWEB)

    Manzanares A, E; Vega C, H R; Leon, L.C. de . [Unidades Academicas de Estudios Nucleares, Universidad Autonoma de Zacatecas, A.P. 336, 98000 Zacatecas (Mexico); Rebolledo D, O; Radillo J, F [Facultad de Ciencias Biologicas y Agropecuarias de la Universidad de Colima, Colima (Mexico)

    2002-07-01

    Lymphocytes, obtained from healthy donors, were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp70 and Hsc70.Hsp70 protein was detected after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 1.25 c Gy gamma-ray dose, lymphocytes expressed Hsp70 protein, indicating a threshold response to gamma rays. (Author)

  15. Cellular response to low Gamma-ray doses

    International Nuclear Information System (INIS)

    Manzanares A, E.; Vega C, H.R.; Leon, L.C. de; Rebolledo D, O.; Radillo J, F.

    2002-01-01

    Lymphocytes, obtained from healthy donors, were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp70 and Hsc70.Hsp70 protein was detected after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 1.25 c Gy gamma-ray dose, lymphocytes expressed Hsp70 protein, indicating a threshold response to gamma rays. (Author)

  16. Gamma irradiators for radiation processing

    International Nuclear Information System (INIS)

    2006-01-01

    Radiation technology is one of the most important fields which the IAEA supports and promotes, and has several programmes that facilitate its use in the developing Member States. In view of this mandate, this Booklet on 'Gamma Irradiators for Radiation Processing' is prepared which describes variety of gamma irradiators that can be used for radiation processing applications. It is intended to present description of general principles of design and operation of the gamma irradiators available currently for industrial use. It aims at providing information to industrial end users to familiarise them with the technology, with the hope that the information contained here would assist them in selecting the most optimum irradiator for their needs. Correct selection affects not only the ease of operation but also yields higher efficiency, and thus improved economy. The Booklet is also intended for promoting radiation processing in general to governments and general public

  17. Observation of galactic gamma radiation

    International Nuclear Information System (INIS)

    Paul, J.A.

    1982-09-01

    A complete and deep survey of the galactic high-energy gamma radiation is now available, thanks to the gamma-ray telescopes on board of the SAS-2 and COS-B spacecrafts. A comparison of the COS-B gamma-ray survey with a fully sampled CO survey together with an Hsub(I) survey is used to show that a simple model, in which uniformly distributed cosmic rays interact with the interstellar gas, can account for almost all the gamma-ray emission observed in the first galactic quadrant. At medium galactic latitudes, it is shown that a relationship exists between the gamma radiation and the interstellar absorption derived from galaxy counts. Therefore gamma rays from the local galactic environment can be used as a valuable probe of the content and structure of the local interstellar medium. The large scale features of the local interstellar gas are revealed, in particular wide concentrations of nearby molecular hydrogen. On a smaller scale, the detection of numerous localized gamma-ray sources focuses the attention on some particular phases of clusters of young and massive stars where diffuse processes of gamma-ray emission may also be at work

  18. Determination of the dose of gamma radiation sterilization for assessment of biological parameters of male Ceratitis capitada (Diptera: Tephritidae), tsl - Vienna 8 strain

    International Nuclear Information System (INIS)

    Rocha, Aline Cristina Pereira da

    2011-01-01

    The Vienna-8, tsl (temperature sensitive lethal) strain of Ceratitis capitata, by presenting mutations that facilitate the mass rearing and release only of sterile males in the field, has been used in (Sterile Insect Technique) programmes. The objective of this study was to determine the radiation dose that provides the highest level of sterility for Vienna-8, tsl males assessing their biological parameters that indicate the quality of sterile males to be released. Brown pupae (males) of the tsl strain were obtained from the mass rearing of the Food Irradiation and Radio entomology laboratory of CENA/USP, and they were irradiated (with gamma radiation - 60 Co) 24 hours before the emergence at rates of 0, 30, 60, 90 and 120 Gy. The determination of the sterilizing dose was based on fertility of sexually mature females of the bisexual strain and not irradiated, mated with males of different treatments. Eggs were collected daily during 6 days, were counted and it was possible to estimate fecundity, and assess the hatching rate. The emergence and flight ability were determined by following the protocol of quality control manual for FAO/IAEA/USDA (2003). To assess the longevity under nutritional stress, the insects were kept a period of 48 h after emergence in the absence of water and food, and after this period, mortality was recorded. The size of the testes (left and right) was obtained by dissecting irradiated and non-irradiated males at the eighth day of life, and measure the testes in an ocular micrometer, considering the maximum length and width of each sample. To determine the sperm number was necessary to dissect the males and break their testicles. No difference was observed in emergence rate, flight ability and longevity of irradiated and non-irradiated males, nor in the fecundity of females mated with males of different treatments. The sterilizing dose that resulted in lower fertility of females was 120 Gy, with 1.5% hatching. Considering the parameters of

  19. Human circulating plasma DNA significantly decreases while lymphocyte DNA damage increases under chronic occupational exposure to low-dose gamma-neutron and tritium β-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Korzeneva, Inna B., E-mail: inna.korzeneva@molgen.vniief.ru [Russian Federal Nuclear Center – All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) 607190, Sarov, 37 Mira ave., Nizhniy Novgorod Region (Russian Federation); Kostuyk, Svetlana V.; Ershova, Liza S. [Research Centre for Medical Genetics, Russian Academy of Medical Sciences, 115478 Moscow, 1 Moskvorechye str. (Russian Federation); Osipov, Andrian N. [Federal Medial and Biological Center named after Burnazyan of the Federal Medical and Biological Agency (FMBTz named after Burnazyan of FMBA), Moscow (Russian Federation); State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Zhivopisnaya, 46, Moscow, 123098 (Russian Federation); Zhuravleva, Veronika F.; Pankratova, Galina V. [Russian Federal Nuclear Center – All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) 607190, Sarov, 37 Mira ave., Nizhniy Novgorod Region (Russian Federation); Porokhovnik, Lev N.; Veiko, Natalia N. [Research Centre for Medical Genetics, Russian Academy of Medical Sciences, 115478 Moscow, 1 Moskvorechye str. (Russian Federation)

    2015-09-15

    Highlights: • The chronic exposure to low-dose IR induces DSBs in human lymphocytes (TM index). • Exposure to IR decreases the level of human circulating DNA (cfDNA index). • IR induces an increase of DNase1 activity (DNase1 index) in plasma. • IR induces an increase of the level of antibodies to DNA (Ab DNA index) in plasma. • The ratio cfDNA/(DNase 1 × Ab DNA × TM) is a potential marker of human exposure to IR. - Abstract: The blood plasma of healthy people contains cell-fee (circulating) DNA (cfDNA). Apoptotic cells are the main source of the cfDNA. The cfDNA concentration increases in case of the organism’s cell death rate increase, for example in case of exposure to high-dose ionizing radiation (IR). The objects of the present research are the blood plasma and blood lymphocytes of people, who contacted occupationally with the sources of external gamma/neutron radiation or internal β-radiation of tritium N = 176). As the controls (references), blood samples of people, who had never been occupationally subjected to the IR sources, were used (N = 109). With respect to the plasma samples of each donor there were defined: the cfDNA concentration (the cfDNA index), DNase1 activity (the DNase1 index) and titre of antibodies to DNA (the Ab DNA index). The general DNA damage in the cells was defined (using the Comet assay, the tail moment (TM) index). A chronic effect of the low-dose ionizing radiation on a human being is accompanied by the enhancement of the DNA damage in lymphocytes along with a considerable cfDNA content reduction, while the DNase1 content and concentration of antibodies to DNA (Ab DNA) increase. All the aforementioned changes were also observed in people, who had not worked with the IR sources for more than a year. The ratio cfDNA/(DNase1 × Ab DNA × TM) is proposed to be used as a marker of the chronic exposure of a person to the external low-dose IR. It was formulated the assumption that the joint analysis of the cfDNA, DNase1, Ab

  20. Effects of different doses of gamma radiation in the conservation and in the physiochemical characteristics of carrot (Daucus carota L.) processed minimally

    International Nuclear Information System (INIS)

    Perecin, Thalita Neme; Arthur, Valter; Silva, Lucia Cristina Aparecida S.; Leite, Daniela Terenzi Stuchi; Wyler, Patricia . E- mail: tperecin@cena.usp.br

    2007-01-01

    The objective of the work was to evaluate the effect of different doses of gamma radiation on the characteristics physic-chemical of carrot (Daucus carota L.) processed minimally, seeking the increase of shelf life and decrease of the microbial load. The carrots were acquired in the commerce of Piracicaba city and taken to the laboratory of Foods Irradiation of CENA/USP, where they were washed in running water, peeled and cut in form of slices. The carrot slices were putted in solution of chlorinated water 15ml/L by 4 minutes, droughts and package in a plastic box of polypropylene. After they were conditioned in plastic containers . After they were irradiated in a source of Cobalt-60, type Gammacell-220 (dose rate of 0.725 kGy/hour) with the doses of: 0 (control), 1,0 and 2,0 kGy and stored in temperature of 5 deg C. They were analyzed: loss of fresh mass, the color (factors L, the, b), the pH, Brix and tetrable acidity, 4,10,16 and 22 days after the irradiation. The delineation experimental used was entirely at random with 10 repetitions for each treatment. By analyze of the obtained results concluded that the irradiation there was not difference significant statistics between the treatments with irradiation and the control. (author)

  1. Radiosurgical lesion of the rat hippocampus using the Leksell gamma knife: relation between radiation dose and functional and structural damage

    Czech Academy of Sciences Publication Activity Database

    Liščák, R.; Vladyka, V.; Novotný Jr., J.; Brožek, G.; Náměstková, Kateřina; Mareš, V.; Hájek, M.; Herynek, V.; Syková, Eva

    2002-01-01

    Roč. 97, č. 5 (2002), s. 666-673 ISSN 0022-3085 Institutional research plan: CEZ:AV0Z5039906 Keywords : radiosurgery * Leksell gamma knife Subject RIV: FH - Neurology Impact factor: 2.626, year: 2002

  2. Environmental gamma radiation monitoring at Visakhapatnam using thermoluminescence dosimeters

    International Nuclear Information System (INIS)

    Swarnkar, M.; Sahu, S.K.; Takale, R.A.; Shetty, P.G.; Pundit, G.G.; Puranik, V.D.

    2012-01-01

    The gamma rays are the most significant part of environmental dose due to its large range and deep penetrating power. The environmental gamma radiation is mainly originated from two sources natural radiation and artificially produced radiation. The natural radiation dose arises from the cosmic radiation (galactic and solar) and from the Earth (terrestrial) surface. In the last few decades there is a growing concern all over the world about radiation and their exposure to population. Thus it is necessary to conduct radiological environmental surveillance. The radiation survey data are useful to establish the natural background gamma radiation levels. Extensive gamma radiation survey was carried out around the surroundings of Vishakhapatnam using Thermoluminescence Dosimeters (TLDs). The CaSO 4 :(0.2 mole %) Dy Teflon TLD discs, specifically designed for environmental gamma radiation monitoring purpose were used. These TLD badge are having very high TL sensitivity, a negligible fading rate and a stable TL response. TLDs were deployed on quarterly basis for two years to obtain the cumulative gamma background radiation levels in the study area. The radiological survey was also carried out by using a calibrated radiation survey meter. The annual dose rates were computed from quarterly values actually found and normalised to 365 days. The environmental gamma radiation levels around Vishakhapatnam were found to be in the range of 0.79 mGy/y to 1.86 mGy/y. It is clearly seen from the results that location to location there is a large variation in external gamma radiation levels. During the cycle of the TLD survey, spot readings of the background radiation levels were taken, both while placing the TLDs and while removing them. The instantaneous dose rates measured using survey meter, are also following the large variation as found in TLDs. It varies between 110 nGy/hr to 210 nGy/hr. (author)

  3. Dose mapping of the multi-purpose gamma irradiation facility

    Energy Technology Data Exchange (ETDEWEB)

    Cabalfin, E G; Lanuza, L G; Villamater, D T [Irradiation Services, Nuclear Services and Training Division, Philippine Nuclear Research Institute, Quezon City (Philippines)

    1989-12-01

    In radiation processing, reliable dosimetry constitutes a very important part of process control and quality assurance. Radiation dosimetry is the only acceptable method to guarantee that the irradiated product has undergone the correct radiation treatment. In preparation therefore, for the routine operation of the newly installed multi-purpose gamma irradiation facility at the Philippine Nuclear Research Institute (PNRI), dose mapping distribution studies were undertaken. Results of dose distribution in air as well as in dummy product are presented. The effects of product bulk density, product geometry and product to source distance on minimum absorbed dose and uniformity ratio have been determined. (Author).

  4. Dose mapping of the multi-purpose gamma irradiation facility

    International Nuclear Information System (INIS)

    Cabalfin, E.G.; Lanuza, L.G.; Villamater, D.T.

    1989-01-01

    In radiation processing, reliable dosimetry constitutes a very important part of process control and quality assurance. Radiation dosimetry is the only acceptable method to guarantee that the irradiated product has undergone the correct radiation treatment. In preparation therefore, for the routine operation of the newly installed multi-purpose gamma irradiation facility at the Philippine Nuclear Research Institute (PNRI), dose mapping distribution studies were undertaken. Results of dose distribution in air as well as in dummy product are presented. The effects of product bulk density, product geometry and product to source distance on minimum absorbed dose and uniformity ratio have been determined. (Author)

  5. Mango conservation, Mangifera indica L., haden variety by gamma radiation

    International Nuclear Information System (INIS)

    Domarco, R.E.

    1989-02-01

    This paper evaluates the chemical characteristics and the mangoes sensorial quality after treatments with different doses of gamma radiation and during a period of storage, with constant conditions of temperature and relative humidity. (author)

  6. Human circulating plasma DNA significantly decreases while lymphocyte DNA damage increases under chronic occupational exposure to low-dose gamma-neutron and tritium β-radiation.

    Science.gov (United States)

    Korzeneva, Inna B; Kostuyk, Svetlana V; Ershova, Liza S; Osipov, Andrian N; Zhuravleva, Veronika F; Pankratova, Galina V; Porokhovnik, Lev N; Veiko, Natalia N

    2015-09-01

    The blood plasma of healthy people contains cell-fee (circulating) DNA (cfDNA). Apoptotic cells are the main source of the cfDNA. The cfDNA concentration increases in case of the organism's cell death rate increase, for example in case of exposure to high-dose ionizing radiation (IR). The objects of the present research are the blood plasma and blood lymphocytes of people, who contacted occupationally with the sources of external gamma/neutron radiation or internal β-radiation of tritium N = 176). As the controls (references), blood samples of people, who had never been occupationally subjected to the IR sources, were used (N = 109). With respect to the plasma samples of each donor there were defined: the cfDNA concentration (the cfDNA index), DNase1 activity (the DNase1 index) and titre of antibodies to DNA (the Ab DNA index). The general DNA damage in the cells was defined (using the Comet assay, the tail moment (TM) index). A chronic effect of the low-dose ionizing radiation on a human being is accompanied by the enhancement of the DNA damage in lymphocytes along with a considerable cfDNA content reduction, while the DNase1 content and concentration of antibodies to DNA (Ab DNA) increase. All the aforementioned changes were also observed in people, who had not worked with the IR sources for more than a year. The ratio cfDNA/(DNase1×Ab DNA × TM) is proposed to be used as a marker of the chronic exposure of a person to the external low-dose IR. It was formulated the assumption that the joint analysis of the cfDNA, DNase1, Ab DNA and TM values may provide the information about the human organism's cell resistivity to chronic exposure to the low-dose IR and about the development of the adaptive response in the organism that is aimed, firstly, at the effective cfDNA elimination from the blood circulation, and, secondly - at survival of the cells, including the cells with the damaged DNA. Copyright © 2015. Published by Elsevier B.V.

  7. III. The effect of various doses of gamma 6OCo radiation upon pollen vitality of China aster (Callistephus chinensis Nees in M1 and M2 generation

    Directory of Open Access Journals (Sweden)

    Alicja Wosińska

    2013-12-01

    Full Text Available The effect of gamma radiation upon pollen was studied in populations of 4 China aster varieties in M1 (plants from irradiated seeds and M2 generation. Effect of radiation Was assessed·in partiicular years. Comparison was rnalde between pollen vitality in irradiated plants and in the control. Effect of radiation was visibly harmful only in case of plants from M1 generation. The effects of radiation were different for particular varieties.

  8. Dose-dependent analysis of acute medical effects of mixed neutron-gamma radiation from selected severe 235U or 239Pu criticality accidents in USSR, United States, and Argentina.

    Science.gov (United States)

    Barabanova, Tatyana; Wiley, Albert L; Bushmanov, Andrey

    2012-04-01

    Eight of the most severe cases of acute radiation disease (ARS) known to have occurred in humans (as the result of criticality accidents) had survival times less than 120 h (herein defined as "early death"). These accidents were analyzed and are discussed with respect to the specific accident scenarios and the resulting accident-specific, mixed neutron-gamma radiation clinical dose distributions. This analysis concludes that the cardiovascular system appears to be the most critical organ system failure for causing "early death" following approximate total body, mixed gamma-neutron radiation doses greater than 40-50 Gy. The clinical data also suggest that there was definite chest dose dependence in the resulting survival times for these eight workers, who unfortunately suffered profound radiation injury and unusual clinical effects from such high dose radiation exposures. In addition, "toxemic syndrome" is correlated with the irradiation of large volumes of soft tissues. Doses to the hands or legs greater than 80-100 Gy or radiation lung injury also play significant but secondary roles in causing "early death" in accidents delivering chest doses greater than 50 Gy.

  9. induction of cytogenetic damage by low doses of acute and chronic gamma-radiation in mammalian and plant cells

    International Nuclear Information System (INIS)

    Zaichkina, S.I.; Aptikaeva, G.F.; Akhmadieva, A.Ch.; Rozanova, O.M.; Smirnova, E.N.; Rogova, N.J.; Ganassi, E.E.

    1997-01-01

    The problem of the biological action of low doses of mutagenic agents has received much attention recently. It is shown that the risk factors for low-dose exposure are greater that it was calculated by extrapolation from higher to lower doses. The aim of the present study was to investigate the effect of low doses on various biological objects including animal and plant cells. (authors)

  10. Induction of cytogenetic damage by low doses of acute and chronic gamma-radiation in mammalian and plant cells

    Energy Technology Data Exchange (ETDEWEB)

    Zaichkina, S.I.; Aptikaeva, G.F.; Akhmadieva, A.Ch.; Rozanova, O.M.; Smirnova, E.N.; Rogova, N.J.; Ganassi, E.E. [Institute of Theoretical and Experimental Biophysics, Moscow (Russian Federation)

    1997-03-01

    The problem of the biological action of low doses of mutagenic agents has received much attention recently. It is shown that the risk factors for low-dose exposure are greater that it was calculated by extrapolation from higher to lower doses. The aim of the present study was to investigate the effect of low doses on various biological objects including animal and plant cells. (authors)

  11. Utilization of thermoluminescent dosemeters for determination of exposure or absorbed dose in a radiation gamma or X radiation field with unknown spectral distribution

    International Nuclear Information System (INIS)

    Rosa, L.A.R. da.

    1981-06-01

    Having in view the choice of the best pair of dosemeters to be used in the 'Tandem' method, the main response characteristics of LiF:Mg, Ti, Li 2 B 4 O 7 :Mn, CaSO 4 Dy, CaF 2 :Mn and CaF 2 :Dy thermoluminescent dosemeters and also some critical parameters in their calibration and evaluation processes were studied. Three different physical forms of TLD's were investigated: hot pressed chips, disc teflon dosemeters and glass mini TLD's. Their calibration factors were obtained for the energy of Cobalt-60 gamma rays. Their energy dependences normalized to 60 Co radiation were determined using spectral width as parameter. 'Tandens' formed by all TLD's evaluated were compaired. (E.G.) [pt

  12. Effects of gamma radiation on potato meristems

    International Nuclear Information System (INIS)

    Fernandez Gonzalez, J.; Garcia Collantes, M.A.

    1976-01-01

    The development of buds in potato tubers subjected to gamma radiation at doses of 3, 6, 8 and 12 Krad is studied at histological level. The irradiation was supplied at the beguining and end of the resting period, and the irradiated buds were observed at different stages of their development. Meristem's sensitivity depends on the state of activity involved at the moment of irradiation. Different parts of the meristem present different radiosensitivity, being the most radioresistant. (author) [es

  13. Gamma Radiation from Fission Fragments

    International Nuclear Information System (INIS)

    Higbie, Jack

    1969-10-01

    The gamma radiation from the fragments of the thermal neutron fission of 235 U has been investigated, and the preliminary data are presented here with suggestions for further lines of research and some possible interpretations of the data. The data have direct bearing on the fission process and the mode of fragment de-excitation. The parameters measured are the radiation decay curve for the time interval (1 - 7) x 10 -10 sec after fission, the photon yield, the total gamma ray energy yield, and the average photon energy. The last three quantities are measured as a function of the fragment mass

  14. Gamma Radiation from Fission Fragments

    Energy Technology Data Exchange (ETDEWEB)

    Higbie, Jack

    1969-10-15

    The gamma radiation from the fragments of the thermal neutron fission of {sup 235}U has been investigated, and the preliminary data are presented here with suggestions for further lines of research and some possible interpretations of the data. The data have direct bearing on the fission process and the mode of fragment de-excitation. The parameters measured are the radiation decay curve for the time interval (1 - 7) x 10{sup -10} sec after fission, the photon yield, the total gamma ray energy yield, and the average photon energy. The last three quantities are measured as a function of the fragment mass.

  15. Analysis of portable gamma flaw detectors concerning radiation hygiene

    International Nuclear Information System (INIS)

    Makarova, T.V.

    1982-01-01

    Design and shields of gamma flaw detectors as one of the main factors responsible for personnel dose were studied. The analysis was conducted using the results of radiation hygienic surveys of gamma flaw detection laboratories functioning constantly in Estonia. It is shown that recently the replacement of GUP apparatuses by flaw detectors of RID and ''Gamma-RID'' (types which have design and shielding advantages is observed. However personnel doses have not reduced considerably for the last 10 years. This fact is attributed to design disadvantages of the RID and ''Gamma-RID'' apparatuses the removing of which will give the decreasing of annual personnel dose by 80 %

  16. Effect of seed treatment with static magnetic field (SMF) and low dose gamma radiation (GR) on grain yield of aerobic rice

    International Nuclear Information System (INIS)

    Kumar, Dinesh; Anand, Anjali; Singh, Bhupinder

    2014-01-01

    Aerobic rice cultivation is gaining popularity as it demands less water. However, poor germination of rice is an important issue in this situation. Seed pretreatment with static magnetic field (SMF) and gamma radiation (GR) at prescribed dose is known to influence the germination, seedling vigour and and yield of many crops. There is a possibility to improve the crop establishment under aerobic situation by physical seed treatment with static-magnetic field (SMF) and gamma radiation (GR) prior to sowing. Hence, a field experiment was conducted at the Indian Agricultural Research Institute, New Delhi during kharif 2012 and 2013 to study the effect of SMF and GR-treated seeds on growth and yield of aerobic rice. The five seed treatments were: SMF 50 mT for 2 hrs, SMF 100 mT for 2 hrs, GR 0.0025 kGy, GR 0.10 kGy and an untreated control. The experiment was laid out in a Randomized Block Design with four replications. Crop (variety 'Pusa Basmati-1121') was direct seeded on 25 th and 24 th June during 2012 and 2013, respectively at a spacing of 25 cm. Treatments GR 0.0025 kGy, SMF (50 mT) and SMF (100 mT) resulted in a significant improvement in grain yield of rice over control and GR dose (0.10 kGy) during both the years. Averaged across two years the grain yield increase by treating the rice seeds with GR 0.0025 kGy, SMF (50 mT) and SMF (100 mT) was 20.1, 17.6 and 14.5%, respectively over the control. Increase in GR dose (0.10 kGy ) was not effective in improving the yield, and was found to be similar to control. It is therefore concluded that treatment of rice seeds either with GR (0.0025 kGy) or SMF (50 mT) holds a great promise in increasing the grain yield of aerobic rice. (author)

  17. Leksell gamma knife lesioning of the rat hippocampus: the relationship between radiation dose and functional and structural damage

    Czech Academy of Sciences Publication Activity Database

    Liščák, R.; Vladyka, V.; Novotný ml., J.; Brožek, G.; Náměstková, K.; Mareš, Vladislav; Herynek, V.; Jirák, D.; Hájek, M.; Syková, E.

    2002-01-01

    Roč. 97, Suppl. 5 (2002), s. 666-673 ISSN 0022-3085 R&D Projects: GA MZd NF5161 Institutional research plan: CEZ:AV0Z5011922 Keywords : Leksell gamma knife * rats * memory Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 2.626, year: 2002

  18. Dose mapping role in gamma irradiation industry

    International Nuclear Information System (INIS)

    Noriah Mod Ali; John Konsoh Sangau; Mazni Abd Latif

    2002-01-01

    In this studies, the role of dosimetry activity in gamma irradiator was discussed. Dose distribution in the irradiator, which is a main needs in irradiator or chamber commissioning. This distribution data were used to confirm the dosimetry parameters i.e. exposure time, maximum and minimum dose map/points, and dose distribution - in which were used as guidelines for optimum product irradiation. (Author)

  19. Study of the antioxidant effect of {alpha}-tocopherol on low-density lipoprotein peroxidation induced at low and high {gamma}-radiation dose rates

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, Abdelouahed [Research Centre on Aging and Department of Medicine, University of Sherbrooke, Sherbrooke, QC, J1H 4C4 (Canada)]. E-mail: abdelouahed.khalil@usherbrooke.ca; Milochevitch, Christelle [Research Centre on Aging and Department of Medicine, University of Sherbrooke, Sherbrooke, QC, J1H 4C4 (Canada)

    2005-02-01

    It is well known that vitamin E ({alpha}-tocopherol, {alpha}-toc) is a very efficient lipid soluble antioxidant and several studies showed its beneficial action in the prevention and reduction of atherosclerosis. However, some in vitro studies suggest a prooxidant role of vitamin E, which could occur under given circumstances. This study was thus designed to investigate the antioxidant vs. prooxidant effect of vitamin E with regards to LDL peroxidation induced under different oxidative stress conditions. LDL was enriched with {alpha}-tocopherol and different {alpha}-toc/LDL ratios were studied (8.0{+-}2.5, 14.3{+-}3.0, 33.3{+-}3.7, 42.7{+-}3.5 and 48.2{+-}4.5 molecules of {alpha}-toc/LDL particle). Enriched and control LDL were oxidized by action of {sup {center_dot}}OH and O{sub 2}{sup {center_dot}}{sup -} free radicals produced by {gamma}-radiolysis at different dose rates. Susceptibility of LDL to oxidation was examined by the measure of conjugated diene and TBARS formation as well as LDL endogenous {alpha}-toc disappearance. Increasing LDL {alpha}-toc concentration reduced the LDL susceptibility to oxidation and their oxidizability. {alpha}-toc disappearance rates were comprised between 43 and 8.3x10{sup -10} M s{sup -1} and decreased with the radiation dose rate. Our results support an antioxidant role for {alpha}-tocopherol at high and low oxidative stress conditions.

  20. Methanolic extract of Moringa oleifera leaf and low doses of gamma radiation alleviated amiodarone-induced lung toxicity in albino rats

    Directory of Open Access Journals (Sweden)

    Hasan Hesham F.

    2016-01-01

    Full Text Available This study aimed to evaluate the effects of methanolic extract of Moringa oleifera (MO and/or low doses of gamma radiation (LDR on amiodarone (AMD-induced lung toxicity in rats. AMD administered to female albino rats (100 mg/kg body weight for 10 consecutive days. Rats received methanolic extract of MO (250 mg/kg bwt for 15 successive days and/or were exposed to whole body LDR (0.25Gy on the 1st and 10th days, up to a total dose of 0.5Gy. MO administration induced a significant decrease in serum tumor necrosis factor-alpha (TNF-α and transforming growth factor-beta (TGF-β levels as well as lactate dehydrogenase (LDH activity. Also, the content of malondialdehyde (MDA and hydroxyproline (HYP was significantly decreased in lung tissue. Furthermore, MO significantly increased reduced glutathione (GSH content in lung tissue as compared with AMD. The histopathological investigation of lung tissue revealed the appearance of interstitial pneumonia in rats treated with AMD. The oral administration of MO and/or exposure to LDR reversed the biochemical and histopathological alterations induced by AMD. It can be posited that MO and LDR might have a considerable role in the prevention of lung toxicity induced by AMD.

  1. Radiation dose electrophysiology procedures

    International Nuclear Information System (INIS)

    Hernandez-Armas, J.; Rodriguez, A.; Catalan, A.; Hernandez Armas, O.; Luque Japon, L.; Moral, S.; Barroso, L.; Rfuez-Hdez, R.

    2006-01-01

    The aim of this paper has been to measure and analyse some of the parameters which are directly related with the doses given to patients in two electrophysiology procedures: diagnosis and ablation with radiofrequency. 16 patients were considered in this study. 13 them had an ablation with radiofrequency at the Unit of Electrophysiology at the University Hospital of the Canaries, La Laguna., Tenerife. The results of skin doses, in the ablation cases, were higher than 2 Gy (threshold of some deterministic effects). The average value was 1.1 Gy. The personal doses, measured under the lead apron, for physician and nurses were 4 and 3 micro Sievert. These results emphasised the necessity of radiation protection measures in order to reduce, ad much as possible, the doses to patients. (Author)

  2. Analysis of the dose-response relationship observed in Sprekelia, Petunia and Impatiens treated with gamma radiation

    International Nuclear Information System (INIS)

    Gonzalez J, J.

    2007-01-01

    The present investigation was carried out in order to verifying if it is possible to establish one or a dose range that directly not at random produces a specific effect independently of the species that is treated. The results show that this can be possible if the ranges settle down based on the specific stocking lethal dose for each specie. (Author)

  3. Dose changes of electrophoretic mobility of lymphocytes of rats' peripheral blood at 60Co gamma-radiation effect

    International Nuclear Information System (INIS)

    Nikitina, I.Yu.; Rodionova, N.K.; Pinchuk, L.B.; Lipskaya, A.I.; Roval', G.N.; Serkiz, Ya.I.

    1992-01-01

    As a result of the obtained data analysis two groups of animals with specific changes of lymphocyte mobility after irradiation with 100 and 400 cGy doses were found. Animals irradiated with 50 cGy doses reacted in a single manner. Apparently it is related with the value of animals' radiosensitivity. 6 refs.; 1 fig.; 1 table. (author)

  4. Concrete for. gamma. radiation shielding

    Energy Technology Data Exchange (ETDEWEB)

    de Azevedo e Souza, A.C. (Rio de Janeiro Univ. (Brazil). Inst. de Quimica); Rogers, J D [Rio de Janeiro Univ. (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

    1980-06-01

    The attenuation characteristics of ..gamma.. radiation in concrete slabs, considering their mechanical resistence and densities were determined. One heavy concrete which was used, was prepared using as additives iron ore and Fe/sub 2/ O/sub 3/ pellets in various grain sizes. Fortran programs were used for analysing data and determining the absorption coefficients and attenuation factors.

  5. Study of the effect of the gamma radiation in polycarbonate

    International Nuclear Information System (INIS)

    Khoury, H.J.; Araujo, E.S. de; Silveira, S.V. da

    1990-01-01

    To estimate the radiation effects in the DUROLON polycarbonate, samples were irradiated with 60 Co gamma beam with doses between 0,2KGy and 50KGy. The results obtained shown variations in the yellowed index above 1KGy dose. Their mechanical proprieties are not changed at interval of this doses. (author) [pt

  6. Gamma Radiation Effect on Titan Yellow Solutions

    International Nuclear Information System (INIS)

    El-Banna, M.

    2012-01-01

    In the present work, the radiation induced color bleaching of Titan yellow dye (TY) in different solvents has been studied. The color bleaching of the dye solutions upon irradiation was followed spectrophotometrically. The % color bleaching of the dyes in different solvent systems was plotted against different gamma irradiation doses used and was determined and the obtained relationships were found to be linear in most cases. These relationships were used as calibration curves to determine the unknown irradiation dose. The results obtained were reproducible and showed differences from calculated values ranging from 10 % to 15 %

  7. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation

    International Nuclear Information System (INIS)

    Gaikwad, Pallavi S.; Panicker, Lata; Mohole, Madhura; Sawant, Sangeeta; Mukhopadhyaya, Rita; Nath, Bimalendu B.

    2016-01-01

    Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarily ancient form of extracellular Hb as evident from the present study. -- Highlights: •Comparison of radiation tolerant Chironomus Hb and radiation sensitive Human Hb. •Amino acid composition of midge and human heme confer differential hydrophobicity. •Heme pocket of evolutionarily ancient midge Hb provide gamma radiation resistivity.

  8. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Gaikwad, Pallavi S. [Stress Biology Research Laboratory, Department of Zoology, Savitribai Phule University, Pune, 411007 (India); Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India); Panicker, Lata [Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India); Mohole, Madhura; Sawant, Sangeeta [Bioinformatics Center, Savitribai Phule Pune University, Pune, 411007 (India); Mukhopadhyaya, Rita [Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India); Nath, Bimalendu B., E-mail: bbnath@gmail.com [Stress Biology Research Laboratory, Department of Zoology, Savitribai Phule University, Pune, 411007 (India)

    2016-08-05

    Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarily ancient form of extracellular Hb as evident from the present study. -- Highlights: •Comparison of radiation tolerant Chironomus Hb and radiation sensitive Human Hb. •Amino acid composition of midge and human heme confer differential hydrophobicity. •Heme pocket of evolutionarily ancient midge Hb provide gamma radiation resistivity.

  9. Doses from radiation exposure

    CERN Document Server

    Menzel, H G

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effecti...

  10. The effect of single and double doses of gamma radiation on pre-rigor mortis filleted saithe

    International Nuclear Information System (INIS)

    Underdahl, B.; Lunde, G.

    1973-01-01

    Saithe, caught off the western coast of Norway, were filleted immediately after killing, packed in plastic bags and irradiated using a cobalt-60 source at the Institutt for Atomenergi, Kjeller. The doses were 50, 100, 150, 50+50 and 50+100 krad. All samples were analysed for their total bacterial count, proteolytic activity, ammonia, total volatile acids, trimethylamine oxide, tri- and dimethylamine and formaldehyde. The organoleptic quality was evaluated by a panel of tasters. Double doses were more effective in reducing the total bacterial count than an equivalent single dose. A close relation was found between the bacterial count and the proteolytic activity. The trimethylamine oxide concentration was found to vary between 33 and 44 mg/100 g muscle, decreasing rapidly in non-irradiated fillets to 3 mg/100 g. In non-irradiated fillets trimethylamine oxide was mainly reduced to trimethylamine and in irradiated fillets to dimethylamine and formaldehyde. A split dose of 50+50 krad may have a favourable effect on the total bacterial number, but the analyses of proteolytic activity, the volatile acids and the trimethylamine indicate that a higher proportion of spoilage bacteria survive. The low proteolytic activity and the high content of DMA/FA prove that the split doses of 50+100 krad as compared with a single dose of 150 krad are particularly favourable in the case of saithe. (Auth.)

  11. Measuring element for detection and dose measurement of gamma radiation and neutrons and manufacturing method for the measuring element

    International Nuclear Information System (INIS)

    Piesch, E.; John, W.

    1979-01-01

    The measuring element consists of a bubble-free glass composed on the basis of metaphosphate material. The detection of the γ-radiation takes place through the photoluminescence of the element, and detection of the neutrons by means of resulting β particles producing Cerenkov radiation in the radioluminescence material, that can be measured. For this purpose in addition to Ag the glass contains As as a second excitable element. (DG) [de

  12. Radiation dose measurements

    International Nuclear Information System (INIS)

    1960-01-01

    About 200 scientists from 28 countries and 5 international organizations met at a symposium on radiation dosimetry held by the International Atomic Energy Agency in June 1960. The aim of the symposium was not so much the description of a large number of measuring instruments as a discussion of the methods used, with special emphasis on those problems which had become important in the context of recent developments, such as the measurement of mixed or very large doses

  13. LD50 and inviably dose of gamma radiation for Musca domestica L., 1758 (diptera: muscidae) pupae aged 1, 2, 3 and 4 days

    International Nuclear Information System (INIS)

    Itepan, Natanael M.; Itepan, Sara E.D.Z.

    2013-01-01

    This experiment was carried out in Biological Control of Domestic Fly 'Eduardo Hiroshi Mizumoto' Laboratory at Entomology and Acarology Department (LEA/ESALQ/USP) and in Food Irradiation and Radioentomology Laboratory (LIARE/CENA/USP). The gamma radiation source that was used is a Co-60 irradiator model Gammabeam-650 of the Atomic Energy of Canada Ltd. whose activity in the beginning of the experiments was 9.8x10 13 Bq. (2,644 Ci). The lots of pupae of Musca domestica had been kept in acclimatized room with 25 ± 2 deg C of temperature and 70 ± 5% of relative humidity, until reaching the desired ages. Lots of pupae of M. domestica that had been used, gotten by the flotation process. They had been irradiated with the ages of 1, 2, 3 and 4 days. The used doses for 1 day pupae was 0 (control) 2.5, 5, 7.5, 10, 12.5, 15, 17.5 20, 22.5, 25, 27.5 and 30 Gy; for 2 days pupae: 0 (control), 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220, 240, 260, 280 and 300 Gy; for 3 days pupae: 0 (control), 0, 40, 80, 120, 160, 200, 240, 280, 320 and 360 Gy; and for 4 days pupae: 0 (control), 40; 80; 120; 160, 200, 240, 280, 320, 360, 400 480 and 520 Gy. The dose rate was about 1,500Gy/hr. At these age intervals, the dose to prevent adult emergence was 25, 220, 360 and 520 Gy and the LD50 was 14.28, 128.04, 243.09 e 353.57 Gy, respectively. (author)

  14. LD50 and inviably dose of gamma radiation for Musca domestica L., 1758 (diptera: muscidae) pupae aged 1, 2, 3 and 4 days

    Energy Technology Data Exchange (ETDEWEB)

    Itepan, Natanael M., E-mail: nmitepan@ifsp.edu.br [Instituto Federal de Sao Paulo (IFSP), Piracicaba, SP (Brazil); Itepan, Sara E.D.Z., E-mail: sarazenitepan@ig.com.br [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia Ciencias e Letras; Arthur, Valter, E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

    2013-07-01

    This experiment was carried out in Biological Control of Domestic Fly 'Eduardo Hiroshi Mizumoto' Laboratory at Entomology and Acarology Department (LEA/ESALQ/USP) and in Food Irradiation and Radioentomology Laboratory (LIARE/CENA/USP). The gamma radiation source that was used is a Co-60 irradiator model Gammabeam-650 of the Atomic Energy of Canada Ltd. whose activity in the beginning of the experiments was 9.8x10{sup 13} Bq. (2,644 Ci). The lots of pupae of Musca domestica had been kept in acclimatized room with 25 ± 2 deg C of temperature and 70 ± 5% of relative humidity, until reaching the desired ages. Lots of pupae of M. domestica that had been used, gotten by the flotation process. They had been irradiated with the ages of 1, 2, 3 and 4 days. The used doses for 1 day pupae was 0 (control) 2.5, 5, 7.5, 10, 12.5, 15, 17.5 20, 22.5, 25, 27.5 and 30 Gy; for 2 days pupae: 0 (control), 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220, 240, 260, 280 and 300 Gy; for 3 days pupae: 0 (control), 0, 40, 80, 120, 160, 200, 240, 280, 320 and 360 Gy; and for 4 days pupae: 0 (control), 40; 80; 120; 160, 200, 240, 280, 320, 360, 400 480 and 520 Gy. The dose rate was about 1,500Gy/hr. At these age intervals, the dose to prevent adult emergence was 25, 220, 360 and 520 Gy and the LD50 was 14.28, 128.04, 243.09 e 353.57 Gy, respectively. (author)

  15. Gamma radiation combined with cinnamon oil to maintain fish quality

    Science.gov (United States)

    Lyu, Fei; Zhang, Jing; Wei, Qianqian; Gao, Fei; Ding, Yuting; Liu, Shulai

    2017-12-01

    Effects of gamma radiation combined with cinnamon oil on quality of Northern Snakehead fish fillets were observed during storage at 4 °C. Fish fillets were treated with 1-5 kGy gamma radiation, 0.05-0.5% cinnamon oil or the combination of radiation and cinnamon oil. The antimicrobial activity increased with radiation dose and cinnamon oil concentration. During storage, the combination of 1 kGy radiation and 0.5% cinnamon oil displayed better inhibiting activities on aerobic plate counts, total volatile basic nitrogen, thiobarbituric acid reaction substances than 1 kGy radiation or 0.5% cinnamon oil used alone. Moreover, the combination could arrive at the similar inhibiting activities of cinnamon oil with higher concentration of 0.5% or radiation with higher dose of 5 kGy. Thus, the combination could decrease the radiation dose and cinnamon oil concentration without decreasing the effect of them on maintaining fish quality.

  16. beta. and. gamma. -comparative dose estimates on Enewetak Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Crase, K.W.; Gudiksen, P.H.; Robison, W.L. (California Univ., Livermore (USA). Lawrence Livermore National Lab.)

    1982-05-01

    Enewetak Atoll in the Pacific is used for atmospheric testing of U.S. nuclear weapons. Beta dose and ..gamma..-ray exposure measurements were made on two islands of the Enewetak Atoll during July-August 1976 to determine the ..beta.. and low energy ..gamma..-contribution to the total external radiation doses to the returning Marshallese. Measurements were made at numerous locations with thermoluminescent dosimeters (TLD), pressurized ionization chambers, portable NaI detectors, and thin-window pancake GM probes. Results of the TLD measurements with and without a ..beta..-attenuator indicate that approx. 29% of the total dose rate at 1 m in air is due to ..beta..- or low energy ..gamma..-contribution. The contribution at any particular site, however, is reduced by vegetation. Integral 30-yr external shallow dose estimates for future inhabitants were made and compared with external dose estimates of a previous large scale radiological survey. Integral 30-yr shallow external dose estimates are 25-50% higher than whole body estimates. Due to the low penetrating ability of the ..beta..'s or low energy ..gamma..'s, however, several remedial actions can be taken to reduce the shallow dose contribution to the total external dose.

  17. beta- and gamma-Comparative dose estimates on Eniwetok Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Crase, K.W.; Gudiksen, P.H.; Robison, W.L.

    1982-05-01

    Eniwetok Atoll is one of the Pacific atolls used for atmospheric testing of U.S. nuclear weapons. Beta dose and gamma-ray exposure measurements were made on two islands of the Eniwetok Atoll during July-August 1976 to determine the beta and low energy gamma-contribution to the total external radiation doses to the returning Marshallese. Measurements were made at numerous locations with thermoluminescent dosimeters (TLD), pressurized ionization chambers, portable NaI detectors, and thin-window pancake GM probes. Results of the TLD measurements with and without a beta-attenuator indicate that approx. 29% of the total dose rate at 1 m in air is due to beta- or low energy gamma-contribution. The contribution at any particular site, however, is somewhat dependent on ground cover, since a minimal amount of vegetation will reduce it significantly from that over bare soil, but thick stands of vegetation have little effect on any further reductions. Integral 30-yr external shallow dose estimates for future inhabitants were made and compared with external dose estimates of a previous large scale radiological survey (En73). Integral 30-yr shallow external dose estimates are 25-50% higher than whole body estimates. Due to the low penetrating ability of the beta's or low energy gamma's, however, several remedial actions can be taken to reduce the shallow dose contribution to the total external dose.

  18. Influence on cell proliferation of background radiation or exposure to very low, chronic gamma radiation

    International Nuclear Information System (INIS)

    Planel, H.; Soleilhavoup, J.P.; Tixador, R.; Richoilley, G.; Conter, A.; Croute, F.; Caratero, C.; Gaubin, Y.

    1987-01-01

    Investigations carried out on the protozoan Paramecium tetraurelia and the cyanobacteria Synechococcus lividus, which were shielded against background radiation or exposed to very low doses of gamma radiation, demonstrated that radiation can stimulate the proliferation of these two single-cell organisms. Radiation hormesis depends on internal factors (age of starting cells) and external factors (lighting conditions). The stimulatory effect occurred only in a limited range of doses and disappeared for dose rates higher than 50 mGy/y

  19. Modification of genetic effects of gamma radiation by laser radiation

    International Nuclear Information System (INIS)

    Khotyljova, L.V.; Khokhlova, S.A.; Khokhlov, I.V.

    1988-01-01

    Full text: Mutants obtained by means of ionizing radiation and chemical mutagens often show low viability and productivity that makes their use in plant breeding difficult. Methods reducing the destructive mutagen action on important functions of plant organism and increasing quality and practical value of induced mutants would be interesting. We believe that one method for increasing efficiency of experimental mutagenesis in plants is the application of laser radiation as a modificator of genetic effects of ionizing radiation and chemical mutagens. Combined exposure of wheat seedlings to a gamma radiation dose of 2 kR and to laser radiation with the wave length of 632.8 nm (power density - 20 mVt/cm 2 , exposure - 30 min.) resulted in reducing the chromosomal aberration percentage from 30.5% in the gamma version to 16.3% in the combined treatment version. A radiosensibilizing effect was observed at additional exposure of gamma irradiated wheat seeds to laser light with the wave length of 441.6 nm where chromosomal aberration percentage increased from 22% in the gamma-irradiation version to 31% in the combined treatment version. By laser radiation it is also possible to normalize mitotic cell activity suppressed by gamma irradiation. Additional seedling irradiation with the light of helium-neon laser (632.8 nm) resulted in recovery of mitotic cell activity from 21% to 62% and increasing the average content of DNA per nucleus by 10%. The influence of only laser radiation on plant variability was also studied and it was shown that irradiation of wheat seeds and seedlings with pulsed and continuous laser light of visible spectrum resulted in phenotypically altered forms in M 2 . Their frequencies was dependent upon power density, dose and radiation wave length. Number of altered forms increased in going from long-wave to short-wave spectrum region. In comparing efficiency of different laser types of pulsed and continuous exposure (dose - 180 J/cm 2 ) 2% of altered

  20. Orchid flowers tolerance to gamma-radiation

    International Nuclear Information System (INIS)

    Kikuchi, Olivia Kimiko

    2000-01-01

    Cut flowers are fresh goods that may be treated with fumigants such as methyl bromide to meet the needs of the quarantine requirements of importing countries. Irradiation is a non-chemical alternative to substitute the methyl bromide treatment of fresh products. In this research, different cut orchids were irradiated to examine their tolerance to gamma-rays. A 200 Gy dose did inhibit the Dendrobium palenopsis buds from opening, but did not cause visible damage to opened flowers. Doses of 800 and 1000 Gy were damaging because they provoked the flowers to drop from the stem. Cattleya irradiated with 750 Gy did not show any damage, and were therefore eligible for the radiation treatment. Cymbidium tolerated up to 300 Gy and above this dose dropped prematurely. On the other hand, Oncydium did not tolerate doses above 150 Gy.(author)

  1. Gamma radiation effects on liofilized human serum

    International Nuclear Information System (INIS)

    Padron Soler, E.; Romay Penabad, Z.; Chavez Ardanza, A.; Hernandez Gonzalez, C.; Martin Gonzalez, O.; Garcia Gonzalez, I.; Prieto Miranda, E.

    1995-01-01

    Human freeze dried serum was artificially contaminated with Flavobacterium sp. for studying the effects of gamma radiation of it. The radiobiological parameters of the contaminator were determined and the sterilization dose was set. The quality of the product irradiated at both, calculated sterilization dose (8.5 kGy) an another one about 25 kGy was determined. It was made according to: sterility testing, total proteins, pH enzymes (alanina-aminotransferase, aspartato-aminotransferase, alkaline phosphatase), protein electrophoresis, fast performance liquid chromatographic and effect on the cellular growth. From the latter was concluded that the calculated sterilization dose was adequate form keeping the biological properties and viability of the irradiated serum. Nevertheless, the dose of 25 k Gy was not adequate because of its dangerous effects on the cell culture

  2. Orchid flowers tolerance to gamma-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Olivia Kimiko E-mail: okikuchi@net.ipen.br

    2000-03-01

    Cut flowers are fresh goods that may be treated with fumigants such as methyl bromide to meet the needs of the quarantine requirements of importing countries. Irradiation is a non-chemical alternative to substitute the methyl bromide treatment of fresh products. In this research, different cut orchids were irradiated to examine their tolerance to gamma-rays. A 200 Gy dose did inhibit the Dendrobium palenopsis buds from opening, but did not cause visible damage to opened flowers. Doses of 800 and 1000 Gy were damaging because they provoked the flowers to drop from the stem. Cattleya irradiated with 750 Gy did not show any damage, and were therefore eligible for the radiation treatment. Cymbidium tolerated up to 300 Gy and above this dose dropped prematurely. On the other hand, Oncydium did not tolerate doses above 150 Gy.(author)

  3. Doses from Medical Radiation Sources

    Science.gov (United States)

    ... Medical Radiation Sources Michael G. Stabin, PhD, CHP Introduction Radiation exposures from diagnostic medical examinations are generally ... of exposure annually to natural background radiation. Plain Film X Rays Single Radiographs Effective Dose, mSv Skull ( ...

  4. Airborne and total gamma absorbed dose rates at Patiala - India

    International Nuclear Information System (INIS)

    Tesfaye, Tilahun; Sahota, H.S.; Singh, K.

    1999-01-01

    The external gamma absorbed dose rate due to gamma rays originating from gamma emitting aerosols in air, is compared with the total external gamma absorbed dose rate at the Physics Department of Punjabi University, Patiala. It has been found out that the contribution, to the total external gamma absorbed dose rate, of radionuclides on particulate matter suspended in air is about 20% of the overall gamma absorbed dose rate. (author)

  5. Gamma-radiation-induced chromosal aberration in human lymphocytes: dose-rate effects in stimulated and non-stimulated cells

    International Nuclear Information System (INIS)

    Liniecki, J.; Bajerska, A.; Wyszynska, K.; Cisowska, B.

    1977-01-01

    Stimulated and non-stimulated human peripheral blood lymphocytes were irradiated acutely and chronically, over 24 h. Dose-effect relationships for dicentric chromosomes were established and various models were fitted to the data. At prolonged irradiations, the yield decreased in basic agreement with the linear-quadratic model of aberration induction. Dose-protraction experiments on PHA + and PHA - lymphocytes, irradiated under various conditions of oxygenation and suspension (culture medium, whole blood) showed that the rejoining time increased from about 3 h in non-stimulated cells to about 10 h after PHA stimulation, and that this retarded rejoining was most likely due to blastic transformation itself and not to other conditions of irradiation

  6. Gamma radiation induced chromosal aberration in human lymphocytes: dose-rate effects in stimulated and non-stimulated cells

    Energy Technology Data Exchange (ETDEWEB)

    Liniecki, J; Bajerska, A; Wyszynska, K [School of Medicine, Lodz (Poland). Div. of Nuclear Medicine and Radiobiology. Medical Research Center; Cisowska, B [Copernicus Municipal Hospital, Lodz (Poland). Oncology Center. Radiotherapy Dept.

    1977-05-01

    Stimulated and non-stimulated human peripheral blood lymphocytes were irradiated acutely and chronically, over 24 h. Dose-effect relationships for dicentric chromosomes were established and various models were fitted to the data. At prolonged irradiations, the yield decreased in basic agreement with the linear-quadratic model of aberration induction. Dose-protraction experiments on PHA/sup +/ and PHA/sup -/ lymphocytes, irradiated under various conditions of oxygenation and suspension (culture medium, whole blood) showed that the rejoining time increased from about 3 h in non-stimulated cells to about 10 h after PHA stimulation, and that this retarded rejoining was most likely due to blastic transformation itself and not to other conditions of irradiation.

  7. Gamma radiation inside closed volumes with thin irradiating walls

    International Nuclear Information System (INIS)

    Karpov, V.I.

    1978-01-01

    The dose rate of gamma radiation inside a parallelepiped with thin radiating walls was calculated. The calculation was based on determining the dose rate from a rectangular plate and subsequently summing the dose rates from all the parallelepiped walls. The dose rate from the rectangular plate was calculated by reducing it to an equivalent plate of infinite length and certain fixed width. When the radiators had constant surface density, the dose rate in the geometric centre of volumes having the form of a parallelepiped was shown to have the least value in the case when the parallelepiped degenerates to a cube

  8. Population doses from terrestrial gamma exposure in China

    International Nuclear Information System (INIS)

    Ren, T.; Wang, Z.; Zhu, C.

    1992-01-01

    In order to estimate terrestrial gamma radiation exposure three nationwide surveys have been completed since 1981. The population-weighted outdoor and indoor arithmetic means of gamma dose rate based on momentary dose rate measurements using a NaI(Tl) environmental radiation meter and high-pressure ionisation chamber are, respectively, 80.3 nGy.h -1 and 120 nGy.h -1 . Based on integrating dose measurement using TLD CaSO 4 /Dy they are 67 nGy.h -1 and 89 nGy.h -1 respectively, and based on natural radionuclides concentrations in soil, determined by gamma spectroscopy analyses, they are 72.8 nGy.h -1 and 102 nGy.h -1 , respectively. These surveys were conducted independently by different groups. The best estimations of population-weighted gamma dose rates in China, based on all these surveys, would be 70 nGy.h -1 and 98 nGy.h -1 for outdoors and indoors, respectively. The annual average of effective dose equivalent is 0.56 mSv. These values are higher than the world averages estimated by UNSCEAR. The main reason is that the concentrations of 232 Th and 40 K in the soil of China are much higher than the world average estimated. (author)

  9. Population doses from terrestrial gamma exposure in China

    Energy Technology Data Exchange (ETDEWEB)

    Ren, T.; Wang, Z.; Zhu, C. (Ministry of Public Health, Beijing, BJ (China))

    1992-01-01

    In order to estimate terrestrial gamma radiation exposure three nationwide surveys have been completed since 1981. The population-weighted outdoor and indoor arithmetic means of gamma dose rate based on momentary dose rate measurements using a NaI(Tl) environmental radiation meter and high-pressure ionisation chamber are, respectively, 80.3 nGy.h[sup -1] and 120 nGy.h[sup -1]. Based on integrating dose measurement using TLD CaSO[sub 4]/Dy they are 67 nGy.h[sup -1] and 89 nGy.h[sup -1] respectively, and based on natural radionuclides concentrations in soil, determined by gamma spectroscopy analyses, they are 72.8 nGy.h[sup -1] and 102 nGy.h[sup -1], respectively. These surveys were conducted independently by different groups. The best estimations of population-weighted gamma dose rates in China, based on all these surveys, would be 70 nGy.h[sup -1] and 98 nGy.h[sup -1] for outdoors and indoors, respectively. The annual average of effective dose equivalent is 0.56 mSv. These values are higher than the world averages estimated by UNSCEAR. The main reason is that the concentrations of [sup 232]Th and [sup 40]K in the soil of China are much higher than the world average estimated. (author).

  10. Inherited influence of low dose gamma radiation on the reproductive potential and spermiogenesis of the cowpea weevil, Callosobruchus maculatus (F (Coleoptera: Chrysomelidae

    Directory of Open Access Journals (Sweden)

    Hatem A. Ibrahim

    2017-10-01

    Full Text Available The southern cowpea weevil, Callosobruchus maculatus (F is a severe agriculture pest worldwide. In the current work, newly emerged adult males of C. maculatus have been irradiated with a low dose of 20Gy gamma radiation. The inherited deleterious effects on the fecundity, hatchability, adult emergence, and the sterility percent were recorded for the progenies F1 and F2 of the irradiated parental males. The fecundity, hatched larvae, the number of males and females were reduced in both F1 and F2. The sterility percent was high in F1 (70.8% and increased in the F2 (88.3% generation. Histopathological effects were also documented in the testes of F1 and F2 progenies. The spermatids and sperms have exhibited a variety of abnormalities. In the early spermatids, the nebenkern outer cell membrane was ruptured. The spermatid nucleus loses its homogeneous texture and has multiple foci of dense chromatin, as well as, profiles range has little dense material. In some groups, the nucleus had a peculiar ring of chromatin. The sperms had shown a variety of aberrations. The sperms irregularity distributed in lysed cysts by unusual manner. Also, some sperms had remarkably enlarged axoneme and small rounded nucleus. Many of the sperm cells were observed with two axonemes, abnormal mitochondria derivatives, and more than two accessory bodies. These results indicate that the low dose of 20 Gy induces semi-sterility in C. maculatus through generations. The same technique would help to improve using of sterile insect technique for other agriculture pests.

  11. Sterilization of peat by gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Parker, F E; Vincent, J M [New South Wales Univ., Kensington (Australia). School of Microbiology

    1981-01-01

    The effect of gamma-radiation on the survival of microorganisms has been quantified for the natural population of two types of peat. Data for several microbial types have been separately determined by regular plating and by indirect statistical probability estimates including, a wholly enclosed 'inverted-bottle' technique for higher dose levels to exclude any possibility of post-treatment contamination. The most persistent microorganisms at intermediate dosage (2.5-3.5 Mrad) were commonly a micrococcus (which closely resembled Micrococcus radiodurans) arthrobacter-like rods, myxobacteria and amoeboid forms. The persistent organisms all survived because of high resistance to ..gamma..-irradiation, not because of high initial numbers. The most numerous true bacteria (including spore-formers), actinomycetes, filamentous fungi and yeasts were all readily destroyed. Although the safety margin with the commercially recommended dose of 5 Mrad is low for some of the more resistant organisms, no change is justified at this stage since the organisms most likely to survive such a dose do not seem to seriously affect the subsequent growth and survival of rhizobia. Moreover there would be some risk of radiation-induced peat toxicity if higher doses were applied and some post-irradiation contamination will be difficult to avoid in commercial production.

  12. Dose-dependent and gender-related radiation-induced transcription alterations of Gadd45a and Ier5 in human lymphocytes exposed to gamma ray emitted by 60Co

    International Nuclear Information System (INIS)

    Tavakoli, H.; Manoochehri, M.; Mosalla, S. M. M.; Ghafori, M.; Karimi, A. A.

    2013-01-01

    Growth arrest DNA damage-inducible 45a gene (Gadd45a) and immediate early response gene 5 (Ier5) have been emphasised as ideal radiation bio-markers in several reports. However, some aspects of radiation-induced transcriptional alterations of these genes are unknown. In this study, gender-dependency and dose-dependency as two factors that may affect radiation induced transcription of Gadd45a and Ier5 genes were investigated. Human lymphocyte cells from six healthy voluntary blood donors (three women and three men) were irradiated in vitro with doses of 0.5-4.0 Gy from a 60 Co source and RNA isolated 4 h later using the High Pure RNA Isolation Kit. Dose and gender dependency of radiation-induced transcriptional alterations of Gadd45a and Ier5 genes were studied by quantitative real-time polymerase chain reaction. The results showed that as a whole, Gadd45a and Ier5 gave responses to gamma rays, while the responses were independent of radiation doses. Therefore, regardless of radiation dose, Gadd45a and Ier5 can be considered potential radiation bio-markers. Besides, although radiation-induced transcriptional alterations of Gadd45a in female and male lymphocyte samples were insignificant at 0.5 Gy, at other doses, their quantities in female samples were at a significantly higher level than in male samples. Radiation induced transcription of Ier5 of females samples had a reduction in comparison with male samples at 1 and 2 Gy, but at doses of 0.5 and 4 Gy, females were significantly more susceptible to radiation-induced transcriptional alteration of Ier5. (authors)

  13. A study on gamma dose rate in Seoul (I)

    International Nuclear Information System (INIS)

    Kim, You Hyun; Kim, Chang Kyun; Choi, Jong Hak; Kim, Jeong Min

    2001-01-01

    This study was conducted to find out gamma dose rate in Seoul, from January to December in 2000, and the following results were achieved : The annual gamma dose rate in Seoul was 17.24 μR/hr as average. The annual gamma dose rate in subway of Seoul was 14.96 μR/hr as average. The highest annual gamma dose rate was Dong-daemon ku. Annual gamma dose rate in Seoul was higher autumn than winter

  14. Gamma dose rate effect on JFET transistors

    International Nuclear Information System (INIS)

    Assaf, J.

    2011-04-01

    The effect of Gamma dose rate on JFET transistors is presented. The irradiation was accomplished at the following available dose rates: 1, 2.38, 5, 10 , 17 and 19 kGy/h at a constant dose of 600 kGy. A non proportional relationship between the noise and dose rate in the medium range (between 2.38 and 5 kGy/h) was observed. While in the low and high ranges, the noise was proportional to the dose rate as the case of the dose effect. This may be explained as follows: the obtained result is considered as the yield of a competition between many reactions and events which are dependent on the dose rate. At a given values of that events parameters, a proportional or a non proportional dose rate effects are generated. No dependence effects between the dose rate and thermal annealing recovery after irradiation was observed . (author)

  15. Risk to Krakow population of gamma radiation from building materials

    International Nuclear Information System (INIS)

    Koperski, J.; Jasinska, M.

    1980-01-01

    A statistics was made of 7128 dwelling-houses considering their age, types of building materials and density of population. Gamma dose rates were measured by means of the TL and pressurized ionization chamber techniques inside 300 buildings and in 44 points outdoors over different kinds of beddings. Personal doses of 49 inhabitants of the buildings monitored were also recorded. By means of the spectrometric analysis of gamma radiation, and basing on a specially developed computational programme ''DOZA'' mean concentrations of 40 K, 226 Ra and 232 Th in 61 samples of building materials were evaluated. It was found that the mean personal dose rate as well as the mean indoor dose rate equals 5.7 urad/h /15.8 pGy/s/ and is about 19% higher than the dose outdoors which equals 4.8 urad/h /13.3 pGy/s/. Gamma dose rates inside the buildings made of gravel-sand concrete elements are about 10% lower than those in the buildings made of red bricks. Mean annual dose equivalent per capita from gamma radiation of building materials equals 40.6 mrem/y /406 uSv/y/, which constitutes about 57% of total annual dose equivalent per capita from all environmental sources of gamma radiation in the residential districts in Krakow. (author)

  16. Gamma radiation effects on peanut skin antioxidants

    Energy Technology Data Exchange (ETDEWEB)

    Camargo, Adriano Costa de [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Canniatti-Brazaca, Solange Guidolin; Vieira, Thais Maria Ferreira de Souza; Regitano-d' Arce, Marisa Aparecida Bismara; Calori-Domingues, Maria Antonia, E-mail: sgcbraza@usp.b, E-mail: tvieira@esalq.usp.b, E-mail: mabra@esalq.usp.b, E-mail: macdomin@esalq.usp.b [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Agroindustria, Alimentos e Nutricao

    2011-07-01

    Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The viability of using natural sources of antioxidants to replace synthetic antioxidants was assessed. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays at a dose rate of 7.5 kGy/h using a {sup 60}Co source. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached deodorized (RBD) soybean oil that was free from synthetic antioxidants. The oxidative stability of the oil samples was determined using the Rancimat method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. Ethanolic extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Rancimat method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT but lower than THBQ. The present study confirmed that gamma radiation did not affect the peanut skin extracts' antioxidative level when added to soybean oil. The induction period of the control soybean oil was 5.7 h, while soybean oil with added ethanolic peanut skin extract had an induction period of 7.2 h, on average. (author)

  17. Gamma radiation effects on peanut skin antioxidants

    International Nuclear Information System (INIS)

    Camargo, Adriano Costa de; Canniatti-Brazaca, Solange Guidolin; Vieira, Thais Maria Ferreira de Souza; Regitano-d'Arce, Marisa Aparecida Bismara; Calori-Domingues, Maria Antonia

    2011-01-01

    Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The viability of using natural sources of antioxidants to replace synthetic antioxidants was assessed. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays at a dose rate of 7.5 kGy/h using a 60 Co source. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached deodorized (RBD) soybean oil that was free from synthetic antioxidants. The oxidative stability of the oil samples was determined using the Rancimat method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. Ethanolic extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Rancimat method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT but lower than THBQ. The present study confirmed that gamma radiation did not affect the peanut skin extracts' antioxidative level when added to soybean oil. The induction period of the control soybean oil was 5.7 h, while soybean oil with added ethanolic peanut skin extract had an induction period of 7.2 h, on average. (author)

  18. Gamma radiation influences postharvest disease incidence of pineapple fruits

    International Nuclear Information System (INIS)

    Damayanti, M.; Sharma, G.J.; Kundu, S.C.

    1992-01-01

    The application of gamma radiation for improving the storage of pineapple fruits [Ananas comosus (L.) Merr. cv. Queen] has been studied in an attempt to reduce decay caused by fungal pathogens such as Ceratocystis paradoxa (Dade)-Moreau and Penicillium purpurogenum Stoll. Gamma radiation at 50, 75, 100, 150, and 250 Gy improved shelf life. The maximum tolerable dose was approximately 250 Gy. Fruits irradiated with up to 150 Gy and then stored at 25 to 28C maintained their texture better than did the controls. Radiation, particularly at doses 250 Gy, caused browning of the skin and softening of tissues. Browning increased with increasing radiation dose and storage duration. Excessively high doses promoted spoilage. Doses in the range of 50 to 250 Gy, in combination with storage at 11 to 13C, can be used to reduce postharvest losses in pineapple due to fungal diseases and senescence, thereby extending shelf life

  19. Effect of gamma radiation on ''in vitro''' efficiency of fungicides

    International Nuclear Information System (INIS)

    Menten, J.O.M.; Oliveira, G.C.X.

    1984-01-01

    The activity of 60 Co gamma radiation on eight fungicides used in post-harvesting treatment of agricultural products, was studied. Rhizoctonia solani was used in biological test as indicator-fungus. The fungicides were submitted to gamma radiation doses of O (control), 1, 10, 100, 1000 and 10.000 kR, samples of the fungicides were added to the PSA culture media to obtain 0, 1, 10 and 100 ppm concentrations of the active component of each product and of each radiation dose. The ED 50 (concentration of fungicide necessary to cause 50% radial reduction of the fungic mycelium) of each fungicide in the different gamma radiation doses was determined. (M.A.C.) [pt

  20. Gamma radiation effects on vitamin C standard solutions

    International Nuclear Information System (INIS)

    Amaro, Jose Daniel V.; Mansur Netto, Elias

    1995-01-01

    This word shows the physical - chemical effects of gamma radiation on standard solutions of vitamin C. Samples with concentration of 50 mg/ml were exposed to different doses of gamma radiations: 1,0 2,5 and 5,0 kGy, using a cobalt-60 source, with storing periods of 0,15 and 30 days. The results showed a vitamin C concentration loss, with a minimum of 17% for the dose of 1,0 kGy immediately after irradiation and a maximum of 81% for the dose of 5 kGy and 30 days after irradiation. (author). 3 refs., 2 tabs

  1. Dose rate modelled for the outdoors of a gamma irradiation

    International Nuclear Information System (INIS)

    Mangussi, J

    2012-01-01

    A model for the absorbed dose rate calculation on the surroundings of a gamma irradiation plant is developed. In such plants, a part of the radiation emitted upwards reach's the outdoors. The Compton scatterings on the wall of the exhausting pipes through de plant roof and on the outdoors air are modelled. The absorbed dose rate generated by the scattered radiation as far as 200 m is calculated. The results of the models, to be used for the irradiation plant design and for the environmental studies, are showed on graphics (author)

  2. Dose rate, mitotic cycle duration, and sensitivity of cell transitions from G1 → S and G2 → M to protracted gamma radiation in root meristems

    International Nuclear Information System (INIS)

    Evans, L.S.; Hof, J.V.

    1975-01-01

    Experiments were designed to determine the relative radiosensitivity of the cell transition points of G1 → S and G2 → M in root meristems of several plant species. Label and mitotic indices and microspectrophotometry were used to measure the proportions of cells in each mitotic cycle stage in root meristems after protracted gamma radiation. The criterion of radiosensitivity was the dose rate needed to produce a tissue with less than 1 percent cells in S and none in M after 3 days of continuous exposure. The results show that DNA is the primary radiation target in proliferative root meristems and that the cycle duration stipulates the time interval of vulnerability. In each species, nonrandom reproducible cell proportions were established with 2C:4C:8C amounts of nuclear DNA after 3 days of exposure. Roots of Helianthus annuus, Crepis capillaris, and Tradescantia clone 02 had 80 percent cells with a 2C amount of DNA and 20 percent had a 4C amount of DNA. In these species the transition point of G1 → S was more radiosensitive than G2 → M. Roots of Pisum sativum and Triticum aestivum had cell proportions at 2C:4C:8C amounts of DNA in frequencies of 0.10 to 0.20:0.40 to 0.60:0.30 to 0.40. In these two species 0.30 to 0.40 cells underwent radiation-induced endoreduplication that resulted from a rapid inhibition of cell transit from G2 → M and a slower impairment of G1 → S. Cells increased from 2C to 4C and from 4C to 8C amounts of DNA during irradiation. The proportions of nuclei with 2C:4C:8C amounts of DNA were dependent in part upon the relative radiosensitivity of the G1 → S and G2 → M control points. The data show the relative radiosensitivity of the transition points from G1 → S and from G2 → M was species specific and unrelated to the cycle duration and mean nuclear DNA content of the plant species

  3. Effect of gamma radiation on electrical and optical properties of (TeO2)

    Indian Academy of Sciences (India)

    Employing dose dependence of the current, some real-time gamma radiation dosimeters have been prepared, which ... are on world over to investigate the influence of gamma radi- ... Employing thermal evaporation in a vacuum, thin films of.

  4. Calibration procedures of area monitors in terms of the Ambient Dose Equivalent H*(10), for gamma, x-ray radiation fields

    International Nuclear Information System (INIS)

    Dieguez Davila, L.E.

    1998-01-01

    In the present thesis procedures for calibrating portable survey meters in terms of the new ICRU quantities H*(10) ambient dose equivalent are discussed. Also the remendations of International Comission on Radiation Protection in their report ICRP 60 that inludes the operational magnitudes that the International Comission of Radiation Units proposed for calibrating area monitors

  5. Bioburden assessment and gamma radiation inactivation patterns in parchment documents

    International Nuclear Information System (INIS)

    Nunes, Inês; Mesquita, Nuno; Cabo Verde, Sandra; Carolino, Maria Manuela; Portugal, António; Botelho, Maria Luísa

    2013-01-01

    Parchment documents are part of our cultural heritage and, as historical artifacts that they are, should be preserved. The aim of this study was to validate an appropriate methodology to characterize the bioburden of parchment documents, and to assess the growth and gamma radiation inactivation patterns of the microbiota present in that material. Another goal was to estimate the minimum gamma radiation dose (D min ) to be applied for the decontamination of parchment as an alternative treatment to the current toxic chemical and non-chemical decontamination methods. Two bioburden assessment methodologies were evaluated: the Swab Method (SM) and the Destructive Method (DM). The recovery efficiency of each method was estimated by artificial contamination, using a Cladosporium cladosporioides spore suspension. The parchment samples' microbiota was typified using morphological methods and the fungal isolates were identified by ITS-DNA sequencing. The inactivation pattern was assessed using the DM after exposure to different gamma radiation doses, and using C. cladosporioides as reference. Based on the applied methodology, parchment samples presented bioburden values lower than 5×10 3 CFU/cm 2 for total microbiota, and lower than 10 CFU/cm 2 for fungal propagules. The results suggest no evident inactivation trend for the natural parchment microbiota, especially regarding the fungal community. A minimum gamma radiation dose (D min ) of 5 kGy is proposed for the decontamination treatment of parchment. Determining the minimal decontamination dose in parchment is essential for a correct application of gamma radiation as an alternative decontamination treatment for this type of documents avoiding the toxicity and the degradation promoted by the traditional chemical and non-chemical treatments. - Highlights: • Characterization of the microbial population of parchment documents. • Study the inactivation pattern of parchment microbiota by gamma radiation. • Assessment of

  6. Galactic structure and gamma radiation

    International Nuclear Information System (INIS)

    Casse, Michel; Cesarsky, Catherine; Paul Jacques

    1977-01-01

    A model of spiral structure of the Galaxy is outlined from radiosynchrotron and gamma observations. The most interesting observations in the galactic context, obtained by the SAS II American satellite are concerned with the distribution of the γ photoemission at energies higher than 10 8 eV, along the galactic equator. The model proposed is in quantitative agreement with the present ideas on the spiral structure of the Galaxy, the galactic magnetic field, and the confinement of cosmic rays by the magnetic field and of the magnetic field by matter. Following the American era, the European COS-B satellite opens the European phase towards an identification of the discrete gamma radiation sources [fr

  7. Degradation of polycarbonate induced by gamma radiation

    International Nuclear Information System (INIS)

    Araujo, E.S. de; Guedes, S.M.L.

    1992-01-01

    Polycarbonate (PC) DUROLON amorphous, of molecular weight 22000 g/mol is used in medical supplies and may be sterilized by gamma radiation. The main chain scission and polymer degradation occur when this polymer is irradiated. The value G = 1.54 to DUROLON was obtained by equation: 10 6 /M v = 10 6 /M v' + 0.054 G R. The degradation without crosslinking it is not general rule to all types of polycarbonates; an comparison was realized. The infrared (FT-IR) spectra of irradiated PC by gamma rays with different doses showed the main chain scissions in carbonyl groups. The mechanism of polymeric degradation to DUROLON, observed by NMR spectra, is a recombination of phenoxy and phenyl radicals. (author)

  8. Use of the gamma radiation, in a dose of 0,4 kGy, on the storage temperature reduction of the banana nanica

    International Nuclear Information System (INIS)

    Manoel, Luciana; Vieites, Rogerio Lopes

    2009-01-01

    The aim was to evaluate the use of gamma radiation, in a dose of 0,4 kGy, on the storage temperature reduction of the banana 'Nanica'. The bananas 'Nanica' were harvested in the Arm Taperao, Brotas (SP) town, and sent to CBE (Companhia Brasileira de Esterilizacao-Cotia-SP) for irradiation and constitution of the following treatments: T1 (fruits irradiated at 0,4 kGy and stored at 16 ±1 deg C); T2 (fruits irradiated at 0,4 kGy and stored at 14 ±1 deg C); T3 (fruit irradiated ata 0,4 kGy and stored at 12±1 deg C); T4 (fruits non-irradiated and stored at 16±1 deg C); T5 (fruits non-irradiated and stored at 14±1 deg C) and T6 (fruits non-irradiated and stored at 12±1 deg C). The fruits were stored in B.O.Ds. of the Agroindustrial Management and Technology Department, with a relative humidity of 80±5%. The experiment was divided in two groups: control group (post harvest conservation and disease incidence) and parcel group (soluble solids and pulp/peel). The analyses were performed in intervals of five days during a period of 25 days. The experimental design employed was completely randomized (DIC) by applying a factor of 2 x 3 x 6 (irradiation x temperature x time). The Tukey test with 5% of probability was used for comparison between means. The storage temperature of the bananas 'Nanica' was not reduce by irradiation. (author)

  9. Soil contaminated phyto remediation of Pb and cd metal by using rice straw fermented by trichoderma viride that given exposure 250 gray doses of gamma radiation

    International Nuclear Information System (INIS)

    Yullita SL Andini; Hendrawati; Tri Retno Diah Larasati; Nana Mulyana

    2015-01-01

    Soil contamination by lead (Pb) and cadmium (Cd) is one form of environmental pollution that is harmful to living organisms. One way to resolve this problem by using phyto remediation with rice straw fermented by Trichoderma viride that given exposure 250 gray doses of gamma radiation. The purpose of this study was to look at the effect of Trichoderma viride fermented hay to improve the ability of Pb and Cd accumulation in the root zone of plants sweet corn (Zea Mays). There are three stages in the research process, namely the stages of SSF (Solid State Fermentation), incorporation, and Land farming. The fermentation process is done during the 16-day trial. Furthermore, the results of the SSF (Solid State Fermentation) mixed in soil that has been contaminated with heavy metals showed that administration of straw result SSF real impact on the value of pH, water content of the four treated samples. Results incorporation process and then applied with a crop of sweet corn (Zea Mays). Accumulation of heavy metals in sweet corn plant, analyzed by AAS analysis instrumentation. The measurement results show that the accumulation of Pb in the roots of plants in the sample K amounted to 33.66 mg/Kg, A sample of 26.80 mg/Kg, the sample B of 51.47 mg/kg, and sample C of 55.70 mg/Kg. While the metals Cd uptake in the roots of corn plants in the sample K showed Cd uptake of 269.65 mg/Kg, the sample A of 445.70 mg/Kg, the sample B of 337.17 mg/Kg and sample C of 336.72 mg/Kg. The phyto remediation process takes place based on the fito-stabilization principle. (author)

  10. Gamma radiation effect study in polycarbonate optical and mechanics properties

    International Nuclear Information System (INIS)

    Araujo, E.S. de.

    1991-02-01

    Polycarbonates (PC) are used in different industrial applications due to their excellent dielectric characteristics, impact resistance, and high temperature resistance. In some of these applications, the polycarbonates are exposed to gamma radiation which produces molecular scissions, causing changes in the polycarbonate properties. To estimate the radiation effects in the Durolon polycarbonate, samples were irradiated with 60 Co gamma rays with doses between 0,2 kGy and 300 kGy. The results obtained showed that the PC mechanical properties are not changed due to the gamma radiation. However the results showed an expressive variation in the yellowness index for doses above 1 kGy. The results showed that it is possible to use the gamma sterilization of PC in applications where the coloration of PC is not critical. (author). 21 refs, 25 figs, 3 tabs

  11. Effect of gamma background on the dose absorbed by human embryon and foetus

    International Nuclear Information System (INIS)

    Miloslavov, V.; Doncheva, B.

    1989-01-01

    A method is proposed for calculation of absorbed radiation dose in different stages of human foetus development under normal or increased gamma background. On the base of ICRP-data for critical organ's mass (foetus, placenta, blood, uterus) a formula is given for absorbed dose evaluation of gonads. It is concluded that increased gamma background is insignificant compared to internal irradiation from absorbed radionuclides

  12. Investigation of PBAT dosimetric properties for high gamma dose dosimetry

    International Nuclear Information System (INIS)

    Cunha, Elisete L.; Schimitberger, Thiago

    2017-01-01

    Poly(butylene adipate-co-terephthalate) (PBAT) is an aliphatic-aromatic copolyester which is biodegradable. It is a non-photoluminescent copolyester that becomes photoluminescent after previous exposure to gamma doses higher than 100 kGy. After the previous high energy irradiation, the material shows the highest photo-stimulated luminescence emission when excited with a LED source at wavelengths ranging from 370 to 405 nm. In this work we investigated the enhancement of the photoluminescence (PL) and dosimetric properties of PBAT, after exposure to high doses of gamma radiation ranging from 50 to 4,000 kGy. In this investigation we demonstrate that increasing the PBAT film thickness by 100 μm enhances the PL output by 3.5 times, when irradiated with 500 kGy. Also, besides the already known color green brightness, the PL intensity can also be used for high dose dosimetry purposes for doses ranging from 50 to 750 kGy. The FTIR analysis has demonstrated that the there is a linear relationship between peak intensity and dose for doses ranging from 100 and 2,000 kGy for the absorbance peaks at 3,241 cm -1 and 3271 cm -1 , with linear correlation coefficients of 0.9981 and 0.9992, respectively. The results indicate that PBAT has great potential for applications in bio-imaging devices and high gamma dose dosimetry. (author)

  13. Investigation of PBAT dosimetric properties for high gamma dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Elisete L.; Schimitberger, Thiago, E-mail: elisete.cunha@cdtn.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Oliveira, Cristiana M.; Faria, Luiz O., E-mail: farialo@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Poly(butylene adipate-co-terephthalate) (PBAT) is an aliphatic-aromatic copolyester which is biodegradable. It is a non-photoluminescent copolyester that becomes photoluminescent after previous exposure to gamma doses higher than 100 kGy. After the previous high energy irradiation, the material shows the highest photo-stimulated luminescence emission when excited with a LED source at wavelengths ranging from 370 to 405 nm. In this work we investigated the enhancement of the photoluminescence (PL) and dosimetric properties of PBAT, after exposure to high doses of gamma radiation ranging from 50 to 4,000 kGy. In this investigation we demonstrate that increasing the PBAT film thickness by 100 μm enhances the PL output by 3.5 times, when irradiated with 500 kGy. Also, besides the already known color green brightness, the PL intensity can also be used for high dose dosimetry purposes for doses ranging from 50 to 750 kGy. The FTIR analysis has demonstrated that the there is a linear relationship between peak intensity and dose for doses ranging from 100 and 2,000 kGy for the absorbance peaks at 3,241 cm{sup -1} and 3271 cm{sup -1}, with linear correlation coefficients of 0.9981 and 0.9992, respectively. The results indicate that PBAT has great potential for applications in bio-imaging devices and high gamma dose dosimetry. (author)

  14. Gamma dose effects valuation on micro computing components

    International Nuclear Information System (INIS)

    Joffre, F.

    1995-01-01

    Robotics in hostile environment raises the problem of micro computing components resistance with gamma radiation cumulated dose. The current aim is to reach a dose of 3000 grays with industrial components. A methodology and an instrumentation adapted to test this type of components have been developed. The aim of this work is to present the advantages and disadvantages bound to the use of industrial components in the presence of gamma radiation. After an analysis of the criteria allowing to justify the technological choices, the different steps which characterize the selection and the assessment methodology used are explained. The irradiation and measures means now operational are mentioned. Moreover, the supply aspects of the chosen components for the design of an industrialized system is taken into account. These selection and assessment components contribute to the development and design of computers for civil nuclear robotics. (O.M.)

  15. Population doses from terrestrial gamma exposure in China

    International Nuclear Information System (INIS)

    Ren, T.; Wang, Z.; Zhu, C.

    1993-01-01

    In order to estimate terrestrial gamma radiation exposures, three nationwide surveys have been completed since 1981. The population weighted outdoor and indoor arithmetic means of gamma dose rates based on momentary measurements using a NaI(T1) environmental radiation meter and a high pressured ionization chamber are 80.3 and 120 nGy.h -1 . The means based on integrating measurements using TLD natural radionuclides concentrations in soil, determined by gamma spectrometry analyses, are 72.8 and 102 nGy.h -1 , respectively. These surveys were conducted independently and equally representative. The best estimation of site-averaged and population weighted gamma dose rates in China, based on all these surveys, would be 70 and 98 nGy.h -1 for indoor and outdoor, respectively. The annual average of effective dose equivalent is 0.56 mSv. These values are higher than the world averages estimated by UNSCEAR. The main reason is that the concentrations of 232 Th and 40 K in soil of China are much higher than the world average estimated. (author). 4 refs, 2 tabs

  16. Decimal reduction dose (D10) and optimal dose determination to eliminate salmonella typhimurium in chicken hamburgers through 60Co gamma radiation

    International Nuclear Information System (INIS)

    Basurto B, H.M.

    2001-01-01

    Under aerobic conditions and at room temperature, decimal reduction dose (D 10 ) of S. typhimurium in casoy broth (TSB) was determined through irradiation, inoculating 9,78 log ufc/mL of a strain during 24±2 hours and obtaining a D 10 of 0,425 kGy. Next, the D 10 value of S. typhimurium inoculated in chicken hamburger with a 9,3 log ufc/g concentration was determined under the same conditions of the previous case, obtaining a D 10 of 0,547 kGy, 22,3% higher than the first value. Then, hamburgers were irradiated at 2, 4 and 6 kGy and kept under storage for 57 days at 2±2 o C. During evaluations, it was observed that there is a synergic effect between the irradiation dose and the time of storage (α=5%) for S. typhimurium inoculated in hamburgers. Besides, in the case of the non-irradiated samples, the number of total coliforms increased from 29 to 4250 NMP/g in day 22, while fecal coliforms increased from 4 to 240 NMP/g during the same period, dropping at the end of storage. In the case of irradiated samples, no coliforms were found (<3 NMP/g). Mesofilic and psicrotrofic bacteria diminished their ability to form colonies proportionally to the applied irradiation doses. Nevertheless, as storage time goes by, these bacteria recover the ability to grow up and cause deterioration. Peroxide rate values of irradiated samples were 100% higher than those of the non-irradiated samples. However, there was no significant difference between samples treated at 2,4 and 6 kGy. Finally, useful life of hamburgers was determined through sensorial evaluation of characteristics such as color, external appearance and smell of raw hamburgers, and taste, smell and texture of fried hamburgers. The results obtained were 13, 19, 41 and 34 days for non-irradiated samples, at 2, 4, and 6 kGy respectively

  17. Gamma radiation hazard to miners in bituminous coal mines

    International Nuclear Information System (INIS)

    Skubacz, K.

    1986-01-01

    Radiation hazard to miners working in 16 bituminous coal mines was determined by a thermoluminescence method. While the miners exposure to gamma radiation is higher than that of the general population, the yearly dose was never found to exceed 5 mSv in any investigated person. Factors contributing to the estimate of the exposure hazard and the need for individual dose monitoring in mines are discussed in more detail. 3 refs., 4 figs. (author)

  18. Labour cost of radiation dose

    International Nuclear Information System (INIS)

    Cook, A.; Lockett, L.E.

    1978-01-01

    In order to optimise capital expenditure on measures to protect workers against radiation it would be useful to have a means to measure radiation dose in money terms. Because labour has to be employed to perform radiation work there must be some relationship between the wages paid and the doses received. Where the next increment of radiation dose requires additional labour to be recruited the cost will at least equal the cost of the extra labour employed. This paper examines some of the factors which affect the variability of the labour cost of radiation dose and notes that for 'in-plant' exposures the current cost per rem appears to be significantly higher than values quoted in ICRP Publication 22. An example is given showing how this concept may be used to determine the capital it is worth spending on installed plant to prevent regular increments of radiation dose to workers. (author)

  19. Localization of the gamma-radiation sources using the gamma-visor

    Directory of Open Access Journals (Sweden)

    Ivanov Kirill E.

    2008-01-01

    Full Text Available The search of the main gamma-radiation sources at the site of the temporary storage of solid radioactive wastes was carried out. The relative absorbed dose rates were measured for some of the gamma-sources before and after the rehabilitation procedures. The effectiveness of the rehabilitation procedures in the years 2006-2007 was evaluated qualitatively and quantitatively. The decrease of radiation background at the site of the temporary storage of the solid radioactive wastes after the rehabilitation procedures allowed localizing the new gamma-source.

  20. Localization of the gamma-radiation sources using the gamma-visor

    International Nuclear Information System (INIS)

    Ivanov, K. E.; Ponomaryev-Stepnoi, N. N.; Stepennov, B. S.; Teterin, Y. A.; Teterin, A. Y.; Kharitonov, V. V.

    2008-01-01

    The search of the main gamma-radiation sources at the site of the temporary storage of solid radioactive wastes was carried out. The relative absorbed dose rates were measured for some of the gamma-sources before and after the rehabilitation procedures. The effectiveness of the rehabilitation procedures in the years 2006-2007 was evaluated qualitatively and quantitatively. The decrease of radiation background at the site of the temporary storage of the solid radioactive wastes after the rehabilitation procedures al lowed localizing the new gamma-source. (author)

  1. Car-borne survey of natural background gamma dose rate in Canakkale region (Turkey)

    International Nuclear Information System (INIS)

    Turhan, S.; Arikan, I. H.; Oquz, F.; Aezdemir, T.; Yuecel, B.; Varinlioqlu, A.; Koese, A.

    2012-01-01

    Natural background gamma radiation was measured along roads in the environs of Canakkale region by using a car-borne spectrometer system with a plastic gamma radiation detector. In addition, activity concentrations of 238 U, 226 Ra, 232 Th and 40 K in soil samples from the Canakkale region were determined by using a gamma spectrometer with an HPGe detector. A total of 92 856 data of the background gamma dose rate were collected for the Canakkale region. The background gamma dose rate of the Canakkale region was mapped using ArcGIS software, applying the geostatistical inverse distance-weighted method. The average and population-weighted average of the gamma dose are 55.4 and 40.6 nGy h -1 , respectively. The corresponding average annual effective dose to the public ranged from 26.6 to 96.8 μSv. (authors)

  2. Decontamination of biological ferment by gamma radiation

    International Nuclear Information System (INIS)

    Sabundjian, Ingrid T.; Salum, Debora C.; Silva, Priscila V.; Furgeri, Camilo; Duarte, Renato; Villavicencio, Anna Lucia C.H.

    2007-01-01

    Biological ferment is a product obtained from pure yeast (Saccharomyces cerevisiae) culture by a suitable technological process and employed to increase the size and porosity of the baker's products. Foods containing high microorganisms count indicate that Good Manufacturing Practices were not applied. The aim of this study was to observe the viability of Dry Biological Ferment after the radiation process using different doses of 60 Co gamma rays and different storage times. Dry baker's yeast Saccharomyces cerevisiae samples were purchased from a local supermarket in Sao Paulo (Brazil) and irradiated at IPEN in a Gammacell source at 0.5, 1.0, 2.0 and 3.0 kGy doses (dose-rate of 3.51 kGy/h) at room temperature (25 deg C). The fluorescent method was performed to observe the viability of yeast cells. The viability decrease with the increase of the radiation dose, as shown: the amount of the viable cell found in the non-irradiated samples (control) at 0 day was 87.2%; 30 days 67.7%; 60 days 77.4% and 90 days 60.1%. With 1.0 kGy at 0 day was 61.4%; 30 days 22.7%; 60 days 56.9% and 90 days 24.2%. With 3.0 kGy at 0 day was 57.00%; at the next periods the most of the cells become not viable. (author)

  3. Dibasic calcium phosphate dihydrate, USP material compatibility with gamma radiation

    Science.gov (United States)

    Betancourt Quiles, Maritza

    Gamma radiation is a commonly used method to reduce the microbial bioburden in compatible materials when it is applied at appropriate dose levels. Gamma irradiation kills bacteria and mold by breaking down the organism’s DNA and inhibiting cell division. The purpose of this study is to determine the radiation dosage to be used to treat Dibasic Calcium Phosphate Dihydrate, USP (DCPD) and to evaluate its physicochemical effects if any, on this material. This material will be submitted to various doses of gamma radiation that were selected based on literature review and existing regulations that demonstrate that this method is effective to reduce or eliminate microbial bioburden in natural source and synthetic materials. Analytical testing was conducted to the DCPD exposed material in order to demonstrate that gamma radiation does not alter the physicochemical properties and material still acceptable for use in the manufacture of pharmaceutical products. The results obtained through this study were satisfactory and demonstrated that the gamma irradiation dosages from 5 to 30 kGy can be applied to DCPD without altering its physicochemical properties. These are supported by the Assay test data evaluation of lots tested before and after gamma irradiation implementation that show no significant statistical difference between irradiated and non irradiated assay results. The results of this study represent an achievement for the industry since they provide as an alternative the use of Gamma irradiation technology to control the microbial growth in DCPD.

  4. Preservation of yams by gamma radiation

    International Nuclear Information System (INIS)

    Bansa, D.; Appiah, V.

    1999-01-01

    Loss of yam in storage due to sprouting is very high. There is the need to investigate the possibility of inhibiting the sprouting of local varieties of yams using gamma radiation. The effect of radiation on the storage yams and the functionality of the irradiated yams in the Ghanaian food system was studied. Yams were purchased from a farm in Nkwanta. Some of the yams were irradiated at an average dose of 120 Gy and a dose rate of 114 Gy/hr. The irradiated yams were stored alongside unirradiated controls in a specially constructed barn and on the ground as is traditionally done by the farmers at ambient temperature for 6 months. The stored yams were processed into some local food products, namely, boiled yam, fried yam and fufu and sensory evaluation carried out on them using the Hedonic Scale Test and analysed by Analysis of variance. Results indicated that all the unirradiated yams sprouted by the 3rd month of storage. 6.2% of the irradiated yams stored on the barn and 18.0% of those stored on the ground sprouted. 2.26% irradiated and 8.0% unirradiated yams stored on the barn compared to 22.0% and 12.0% respectively of the yams stored on the ground got rotten within the storage period. Food products made from irradiated yams were preferred to those made from the unirradiated yams in terms of texture, taste, colour and general acceptability. The results suggest that gamma radiation dose of 120 Gy effectively inhibited the sprouting of yams for 6 months under tropical ambient conditions. There was less rotting in the yams stored in the barn compared to those stored on the ground. There was also less rotting in the irradiated yams stored in the barn in comparison with the unirradiated ones. Food products made from irradiated yams were judged better in quality than those made from the unirradiated ones. (au)

  5. 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.

  6. Effect of gamma radiation on growth, productivity and protein content of chlorella pyrenoidosa

    International Nuclear Information System (INIS)

    Fernandez Gonzalez, J.; Martin Moreno, C.

    1983-01-01

    The effect of five doses of gamma radiation: 10, 100, 500, 1000 and 5000 Gy at a dose rate of 4.500 Gy/h on growth, productivity and protein content of Chlorella Pyroneidosa has been studied. High doses of gamma radiation have been observed to inhibit cellular division of Chlorella Pyrenoidosa. Culture growth stopped 48 hours after irradiation at 5.000 Gy and 72 hours after irradiation at 500 and 1000 Gy. The lowest dose (10 Gy) produced a little growth stimulation that as not statistically significative. Protein and aminoacid content did not show any change for gamma radiation doses studied. (author)

  7. Effect of gamma radiation on growth, productivity and protein content of Chlorella Pyrenoidosa

    International Nuclear Information System (INIS)

    Martin Moreno, C.; Fernandez Gonzalez, J.

    1983-01-01

    The effect of five doses of gamma radiation: 10, 100, 500, 1000 and 5000 Gy at a dose rate of 4.500 Gy/h on growth, productivity and protein content of Chlorella pyroneidosa has been studied. High doses of gamma radiation have been observed to inhibit cellular division of Chlorella pyrenoidosa. Culture growth stopped 48 hours after irradiation at 5.000 Gy and 72 hours after irradiation at 500 and 1000 Gy. The lowest dose (10 Gyl produced a little growth stimulation that not statistically significative. Protein and aminoacid content did not show any change for gamma radiation doses studied. (Author) 32 refs

  8. Investigation of the effect of gamma radiation on lincomycin

    International Nuclear Information System (INIS)

    Al-Zier, A; Al- Kassiri, H.; Al Aji, Z.

    2001-01-01

    Sterilization of materials used in medical applications is necessary. Since the use of ethylene oxide will be forbidden in the next future and other sterilization methods as wet, and dry hot sterilization are not suitable for sterilization of drugs, further methods are needed which do not cause a significant decrease in the physical and chemical drug properties. Radiation sterilization can help in many cases. So Gamma or electron radiations were used for sterilization of antibiotics in the solid state as mentioned in the literature. Some antibiotics are already exposed to gamma or electron beam irradiation, and showed significant radiation resistance for low doses, but even small amounts of degradation products are not desirable

  9. Calculation of dose conversion factors for doses in the fingernails to organ doses at external gamma irradiation in air

    International Nuclear Information System (INIS)

    Khailov, A.M.; Ivannikov, A.I.; Skvortsov, V.G.; Stepanenko, V.F.; Orlenko, S.P.; Flood, A.B.; Williams, B.B.; Swartz, H.M.

    2015-01-01

    Absorbed doses to fingernails and organs were calculated for a set of homogenous external gamma-ray irradiation geometries in air. The doses were obtained by stochastic modeling of the ionizing particle transport (Monte Carlo method) for a mathematical human phantom with arms and hands placed loosely along the sides of the body. The resulting dose conversion factors for absorbed doses in fingernails can be used to assess the dose distribution and magnitude in practical dose reconstruction problems. For purposes of estimating dose in a large population exposed to radiation in order to triage people for treatment of acute radiation syndrome, the calculated data for a range of energies having a width of from 0.05 to 3.5 MeV were used to convert absorbed doses in fingernails to corresponding doses in organs and the whole body as well as the effective dose. Doses were assessed based on assumed rates of radioactive fallout at different time periods following a nuclear explosion. - Highlights: • Elemental composition and density of nails were determined. • MIRD-type mathematical human phantom with arms and hands was created. • Organ doses and doses to nails were calculated for external photon exposure in air. • Effective dose and nail doses values are close for rotational and soil surface exposures.

  10. Effects of chemical sensitizers on gamma radiation processing of ...

    African Journals Online (AJOL)

    The potential of gamma radiation processing in cross-linking natural rubber latex (NRL) for production of dipped goods has been studied. NRL produced in Ghana was irradiated to 10, 20, 30, 40 and 50 kGy, respectively, in a Gamma Chamber of dose rate 0.65 kGy/h. Irradiation of the NRL was also carried out in the ...

  11. Effect of large dose gamma-ray irradiation on polyimide

    International Nuclear Information System (INIS)

    Morita, Yohsuke; Watanabe, Kiyoshi; Yagyu, Hideki.

    1988-01-01

    In the radiation environment of atomic energy, space and so on, with the heightening of the performance of equipment, the organic materials having the radiation resistance up to several hundreds MGy have been demanded. Polyimide is one of a small number of the polymers which are considered to be applicable to such environment. However, actually the characteristics as the insulator for such large dose radiation environment have not been sufficiently verified. In this study, the gamma-ray of as large dose as 100 MGy was irradiated on the polyimides having different chemical structure in the air and in nitrogen, and the change of their mechanical and electrical characteristics was elucidated, at the same time, the structural change was examined. The four kinds of polyimides used for the experiment were three kinds of thermosetting type and thermoplastic polyether imide. Co-60 gamma-ray was irradiated at the dose rate of 17 kGy/h at room temperature. The tensile properties, volume resistivity, dielectric tangent, gel fraction, glass transition temperature and IR spectra were examined. In the air, the characteristics lowered by large dose irradiation due to the severance of main chains. In nitrogen, the deterioration was extremely slight, and cross-linking occurred. (K.I.)

  12. Dosimetric studies for gamma radiation validation of medical devices

    International Nuclear Information System (INIS)

    Soliman, Y.S.; Beshir, W.B.; Abdel-Fattah, A.A.; Abdel-Rehim, F.

    2013-01-01

    The delivery and validation of a specified dose to medical devices are key concerns to operators of gamma radiation facilities. The objective of the present study was to characterize the industrial gamma radiation facility and map the dose distribution inside the product-loading pattern during the validation and routine control of the sterilization process using radiochromic films. Cardboard phantoms were designed to achieve the homogeneity of absorbed doses. The uncertainty of the dose delivered during validation of the sterilization process was assessed. - Highlights: ► Using γ-rays for sterilization of hollow fiber dialyzers and blood tubing sets according to ISO 11137, 2006. ► Dosimetry studies of validations of γ-irradiation facility and sterilized medical devices. ► Places of D min and D max have been determined using FWT-60 films. ► Determining the target minimum doses required to meet the desired SAL of 10 −6 for the two products.

  13. Effects of gamma radiation in cauliflower (Brassica spp) minimally processed

    International Nuclear Information System (INIS)

    Nunes, Thaise C.F.; Rogovschi, Vladimir D.; Thomaz, Fernanda S.; Trindade, Reginaldo A.; Villavicencio, Anna L.C.H.; Alencar, Severino M.

    2007-01-01

    Consumers demand for health interests and the latest diet trends. The consumption of vegetables worldwide has increased every year over the past decade, consequently, less extreme treatments or additives are being required. Minimally processed foods have fresh-like characteristics and satisfy the new consumer demand. Food irradiation is an exposure process of the product to controlled sources of gamma radiation with the intention to destroy pathogens and to extend the shelf life. Minimally processed cauliflower (Brassica oleraceae) exposed to low dose of gamma radiation does not show any change in sensory attributes. The aim of this study was to analyze the effects of the low doses of gamma radiation on sensorial aspects like appearance, texture and flavor of minimally processed cauliflower. (author)

  14. Virtual Gamma Ray Radiation Sources through Neutron Radiative Capture

    Energy Technology Data Exchange (ETDEWEB)

    Scott Wilde, Raymond Keegan

    2008-07-01

    The countrate response of a gamma spectrometry system from a neutron radiation source behind a plane of moderating material doped with a nuclide of a large radiative neutron capture cross-section exhibits a countrate response analogous to a gamma radiation source at the same position from the detector. Using a planar, surface area of the neutron moderating material exposed to the neutron radiation produces a larger area under the prompt gamma ray peak in the detector than a smaller area of dimensions relative to the active volume of the gamma detection system.

  15. In vitro mutants identification of banana (Musa sp.) with tolerance to toxin from Fusarium oxysporum f. sp cubense, treating buds with several gamma radiation doses

    International Nuclear Information System (INIS)

    Moura, Adriana Muniz Mendes de; Houllou-Kido, Laureen Michelle; Franca, Jose Geraldo Eugenio de; Colaco, Waldeciro

    1999-01-01

    Mutants of banana, obtained through treatment with different level of gamma-radiation (0; 10; 20; 30; 40 Gy), were initially cultivated in vitro in medium for rapid clonal propagation during 30 days. These treatment affected the shoot tips development ratio. Some plants developed necrosis and died, but some of the shoot tips emitted new gems. These material were cultivated in medium 20% of the toxin of Fusarium oxysporum cubense. During the selection period, the necrosis occurrence and death of susceptible shoot tips were observed. Whereas the tolerant shoot tips kept themselves green during the entire selection process. At the end of the selection process, eight shoot tips were obtained. (author)

  16. Effect of low gamma ray doses on sugar beet

    International Nuclear Information System (INIS)

    Al-Oudat, M.

    1993-01-01

    We studied the effect of presowing irradiation simulation on sugar beet seeds in two regions (Deir Elzour and Damascus) and for three successive cropping seasons (1986-1989). Those seeds were irradiated with gamma radiation doses varying from 0.005 to 0.050 kGy in the first region, and from 0.005 to 0.025 kGy in the second region. Results showed that doses varying from 0.005 to 0.05 kGy in Deir Elzour gave a mean yield increase varying from 17.4% to 22.6%. However, doses varying from 0.005 to 0.025 in Damascus gave an increase of the same parameter between 19.5% and 23.8%. The best results for pure sugar yield increase obtained for a dose of 0.015 kGy (27.1% in Deir Elzour and 31.9% in Damascus). Yields on the farm level obtained from presowing irradiated seeds showed an increase in sugar beets when using 0.015 kGy gamma radiation dose. (author)

  17. Methodology for setting the reference levels in the measurements of the dose rate absorbed in air due to the environmental gamma radiation

    International Nuclear Information System (INIS)

    Dominguez Ley, Orlando; Capote Ferrera, Eduardo; Caveda Ramos, Celia; Alonso Abad, Dolores

    2008-01-01

    Full text: The methodology for setting the reference levels of the measurements of the gamma dose rate absorbed in the air is described. The registration level was obtained using statistical methods. To set the alarm levels, it was necessary to begin with certain affectation level, which activates the investigation operation mode when being reached. It is was necessary to transform this affectation level into values of the indicators selected to set the appearance of an alarm in the network, allowing its direct comparison and at the same time a bigger operability of this one. The affectation level was assumed as an effective dose of 1 mSv/y, which is the international dose limit for public. The conversion factor obtained in a practical way as a consequence of the Chernobyl accident was assumed, converting the value of annual effective dose into values of effective dose rate in air. These factors are the most important in our work, since the main task of the National Network of Environmental Radiological Surveillance of the Republic of Cuba is detecting accidents with a situations regional affectation, and this accident is precisely an example of pollution at this scale. The alarm level setting was based on the results obtained in the first year of the Chernobyl accident. For this purpose, some transformations were achieved. In the final results, a correction factor was introduced depending on the year season the measurement was made. It was taken into account the influence of different meteorological events on the measurement of this indicator. (author)

  18. Preparation of cobra (Naja naja) venom toxoid using gamma-radiations. Part I

    International Nuclear Information System (INIS)

    Gaitonde, B.B.; Kankonkar, S.R.

    1975-01-01

    Detoxification of venom by radiation was investigated. Two concentrations i.e. 0.01% of venom solution were irradiated with different doses of gamma-radiations from cobalt-60 source. The results obtained indicate that the toxicity of venom is markedly attenuated by gamma-radiation. (author)

  19. Radiation doses - maps and magnitudes

    International Nuclear Information System (INIS)

    1989-01-01

    A NRPB leaflet in the 'At-a-Glance' Series presents information on the numerous sources and magnitude of exposure of man to radiation. These include the medical use of radiation, radioactive discharges to the environment, cosmic rays, gamma rays from the ground and buildings, radon gas and food and drink. A Pie chart represents the percentage contribution of each of those sources. Finally, the terms becquerel, microsievert and millisievert are explained. (U.K.)

  20. Radiation dose in dental radiology

    International Nuclear Information System (INIS)

    Cohnen, M.; Kemper, J.; Moedder, U.; Moebes, O.; Pawelzik, J.

    2002-01-01

    The aim of this study was to compare radiation exposure in panoramic radiography (PR), dental CT, and digital volume tomography (DVT). An anthropomorphic Alderson-Rando phantom and two anatomical head phantoms with thermoluminescent dosimeters fixed at appropriate locations were exposed as in a dental examination. In PR and DVT, standard parameters were used while variables in CT included mA, pitch, and rotation time. Image noise was assessed in dental CT and DVT. Radiation doses to the skin and internal organs within the primary beam and resulting from scatter radiation were measured and expressed as maximum doses in mGy. For PR, DVT, and CT, these maximum doses were 0.65, 4.2, and 23 mGy. In dose-reduced CT protocols, radiation doses ranged from 10.9 to 6.1 mGy. Effective doses calculated on this basis showed values below 0.1 mSv for PR, DVT, and dose-reduced CT. Image noise was similar in DVT and low-dose CT. As radiation exposure and image noise of DVT is similar to low-dose CT, this imaging technique cannot be recommended as a general alternative to replace PR in dental radiology. (orig.)

  1. Gamma regularization based reconstruction for low dose CT

    International Nuclear Information System (INIS)

    Zhang, Junfeng; Chen, Yang; Hu, Yining; Luo, Limin; Shu, Huazhong; Li, Bicao; Liu, Jin; Coatrieux, Jean-Louis

    2015-01-01

    Reducing the radiation in computerized tomography is today a major concern in radiology. Low dose computerized tomography (LDCT) offers a sound way to deal with this problem. However, more severe noise in the reconstructed CT images is observed under low dose scan protocols (e.g. lowered tube current or voltage values). In this paper we propose a Gamma regularization based algorithm for LDCT image reconstruction. This solution is flexible and provides a good balance between the regularizations based on l 0 -norm and l 1 -norm. We evaluate the proposed approach using the projection data from simulated phantoms and scanned Catphan phantoms. Qualitative and quantitative results show that the Gamma regularization based reconstruction can perform better in both edge-preserving and noise suppression when compared with other norms. (paper)

  2. Optical fiber sensor for low dose gamma irradiation monitoring

    Science.gov (United States)

    de Andrés, Ana I.; Esteban, Ã.`scar; Embid, Miguel

    2016-05-01

    An optical fiber gamma ray detector is presented in this work. It is based on a Terbium doped Gadolinium Oxysulfide (Gd2O2S:Tb) scintillating powder which cover a chemically etched polymer fiber tip. This etching improves the fluorescence gathering by the optical fiber. The final diameter has been selected to fulfill the trade-off between light gathering and mechanical strength. Powder has been encapsulated inside a microtube where the fiber tip is immersed. The sensor has been irradiated with different air Kerma doses up to 2 Gy/h with a 137Cs source, and the spectral distribution of the fluorescence intensity has been recorded in a commercial grade CCD spectrometer. The obtained signal-to-noise ratio is good enough even for low doses, which has allowed to reduce the integration time in the spectrometer. The presented results show the feasibility for using low cost equipment to detect/measure ionizing radiation as gamma rays are.

  3. Are low radiation doses Dangerous?

    International Nuclear Information System (INIS)

    Garcia Lima, O.; Cornejo, N.

    1996-01-01

    In the last few years the answers to this questions has been affirmative as well as negative from a radiation protection point of view low doses of ionizing radiation potentially constitute an agent causing stochasting effects. A lineal relation without threshold is assumed between dose and probability of occurrence of these effects . Arguments against the danger of probability of occurrence of these effects. Arguments again the danger of low dose radiation are reflected in concepts such as Hormesis and adaptive response, which are phenomena that being studied at present

  4. Effect of gamma radiation on chemical composition and storability of lime RTS

    International Nuclear Information System (INIS)

    Pandey, S.K.; Bisen, A.; Dwivedi, V.

    2008-01-01

    In the present investigation, the RTS was irradiated with different doses of gamma radiation to study their effect on chemical composition and storability of lime RTS and vitamin C content only was influenced significantly by 50 Gy gamma radiation during storage (16 days) without adversely affecting the quality of lime fruits, whereas, under control and higher doses of gamma radiation, the quality of lime RTS was deteriorated. The irradiation of lime with 50 Gy gamma radiation may be useful for extending storability of lime of RTS and stabilizing the market demand. (author)

  5. Effect of doxorubicin on cell survival and micronuclei formation in HeLa cells exposed to different doses of gamma-radiation

    International Nuclear Information System (INIS)

    Jagetia, G.C.; Nayak, V.

    2000-01-01

    Purpose: The present study was undertaken to obtain an insight into the combined effects of doxorubicin with radiation on the cell survival and micronuclei induction in HeLa cells. Material and Methods: HeLa S3 cells were allowed to grow till they reached plateau phase, inoculated with 10 μg/ml doxorubicin hydrochloride and then exposed to 0, 0.5, 1, 2 and 3 Gy γ-radiation. Clonogenicity of cell was measured using the colony forming assay, micronuclei formation using the micronucleus assay. Results: The treatment of HeLa cells with doxorubicin (adriamycin) for 2 hours before exposure to different doses of γ-radiation resulted in a significant and dose-dependent decline in the cell survival and cell proliferation when compared to the PBS+irradiation group. Conversely, the frequency of micronuclei increased in a dose-related manner in both the PBS+irradiation and doxorubicin+irradiation groups. The pretreatment of HeLa cells with doxorubicin before irradiation to various doses of γ-rays resulted in a significant elevation in the frequency of micronuclei when compared with the concurrent PBS+irradiation group. The dose-response relationship for both PBS+irradiation and doxorubicin+irradiation groups was linear. The correlation between cell survival and micronuclei induction was also determined for PBS or doxorubicin+irradiation group, where the clonogenicity of cells declined with the increase in micronuclei formation. The correlation between cell survical and micronuclei induction was linear quadratic for both PBS+irradiation and doxorubicin+irradiation groups. Conclusion: From our study it can be concluded that combination treatment with doxorubicin and radiation increased the genotoxic effect of the either treatment given alone. (orig.) [de

  6. Prenatal radiation doses from radiopharmaceuticals

    International Nuclear Information System (INIS)

    Rojo, A.M.; Gomez Parada, I.M.; Di Trano, J.L.

    1998-01-01

    The radiopharmaceutical administration with diagnostic or therapeutic purpose during pregnancy implies a prenatal radiation dose. The dose assessment and the evaluation of the radiological risks become relevant due to the great radiosensitivity of the fetal tissues in development. This paper is a revision of the available data for estimating fetal doses in the cases of the more frequently used radiopharmaceuticals in nuclear medicine, taking into account recent investigation in placental crossover. The more frequent diagnostic and therapeutic procedures were analyzed according to the radiation doses implied. (author) [es

  7. Automation of the monitoring in real time of the absorbed dose rate in air due to the environmental gamma radiation in Cuba; Automatizacion del monitoreo en tiempo real de la tasa de dosis absorbida en aire debido a la radiacion gamma ambiental en Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez L, O; Capote F, E; Carrazana G, J A; Manzano de Armas, J F; Alonso A, D; Prendes A, M; Zerquera, J T; Caveda R, C A [CPHR, Calle 20, No. 4113 e/41 y 47, Playa, La Habana, 11300, A.P. 6195 C.P. 10600 (Cuba); Kalberg, O [Swedish Radiation Protection Institute (SSI) (Sweden); Fabelo B, O; Montalvan E, A [CIAC, Camaguey (Cuba); Cartas A, H [CEAC, Cienfuegos (Cuba); Leyva F, J C [CISAT (Cuba)

    2006-07-01

    The Center of Protection and Hygiene of the Radiations (CPHR) like center rector of the National Net of Environmental Radiological Surveillance (RNVRA), it has strengthened their detection capacity and of answer before a situation of radiological emergency. The measurements of the absorbed dose rate in air due to the environmental gamma radiation in the main stations of the Net are obtained in real time and the CPHR receives the data coming from these posts at one time relatively short. To improve the operability of the RNVRA it was necessary to complete the facilities of existent monitoring using 4 automatic measurement stations with probes of gamma detection, implementing in this way a measurement system on real time. On the other hand the software were developed: GenironProbeFech, to obtain the data of the probes, DataMail for the shipment of the same ones by electronic mail and GammaRed that receives and processes the data in the rector center. (Author)

  8. Resistance of Salmonella enteritidis variety typhimurium to gamma radiation

    International Nuclear Information System (INIS)

    Norberg, A.N.; Maliska, C.

    1988-01-01

    The use of ionizing radiations to kill microrganisms responsible for food deterioration, and toxinfections is an example of peaceful use of nuclear energy. Food toxinfections are, amongus, produced mostly by Salmonella enteritidis var. typhimurium. Due to the pauncity of information on the resistance to gamma radiation of Salmonella enteritidis var. typhimurium this paper has the aim to define the 60-Cobalt gamma radiation lethal dose to these bacteria, in experimentally contaminated milk by samples recovered from our geographycal area. One hundred nineteen samples of milk containing about 150.000 bacteria per ml were irradiated with doses ranging from 100 to 1.100 Gy. Two samples of surving bacteria were again irradiated by doses up to 2.500 Gy. The bacteria not previously irradiated were killed by doses of 1.100 Gy. It was concluded that the 60-Cobalt gamma radiation minimal lethal dose to Salmonella enteritidis var. typhimurium is 1.200 Gy. The surviving strains to smaller doses than 1.200 Gy when re-irradiated prompt the forthcoming of more radio-resistant germs. (author) [pt

  9. Indoor gamma dose measurements in Gudalore (India) using TLD

    International Nuclear Information System (INIS)

    Sivakumar, R.; Selvasekarapandian, S.; Mugunthamanikandan, N.; Raghunath, V.M.

    2002-01-01

    Indoor gamma radiation dose rates were measured inside residential buildings in Gudalore using a CaSO 4 : Dy thermoluminescent dosimeter for 1 year . Significant seasonal variations are observed. The highest dose rate is observed during summer and the lowest in winter. The dose rates observed are between 77.9 and 229.3 nGy h -1 and may be attributed to the type of building materials used in the dwellings monitored. The calculated mean annual effective dose equivalent rates range between 477.6 μSv y -1 , for the inhabitants of mud houses to 1406.3 μSv y -1 , for those living in terrace houses made of cement and brick

  10. Indoor gamma dose measurements in Gudalore (India) using TLD

    Energy Technology Data Exchange (ETDEWEB)

    Sivakumar, R.; Selvasekarapandian, S. E-mail: spandian@bharathi.ernet.in; Mugunthamanikandan, N.; Raghunath, V.M

    2002-06-01

    Indoor gamma radiation dose rates were measured inside residential buildings in Gudalore using a CaSO{sub 4} : Dy thermoluminescent dosimeter for 1 year . Significant seasonal variations are observed. The highest dose rate is observed during summer and the lowest in winter. The dose rates observed are between 77.9 and 229.3 nGy h{sup -1} and may be attributed to the type of building materials used in the dwellings monitored. The calculated mean annual effective dose equivalent rates range between 477.6 {mu}Sv y{sup -1}, for the inhabitants of mud houses to 1406.3 {mu}Sv y{sup -1}, for those living in terrace houses made of cement and brick.

  11. Semiconductor scintillator detector for gamma radiation

    International Nuclear Information System (INIS)

    Laan, F.T.V. der; Borges, V.; Zabadal, J.R.S.

    2015-01-01

    Nowadays the devices employed to evaluate individual radiation exposition are based on dosimetric films and thermoluminescent crystals, whose measurements must be processed in specific transductors. Hence, these devices carry out indirect measurements. Although a new generation of detectors based on semiconductors which are employed in EPD's (Electronic Personal Dosemeters) being yet available, it high producing costs and large dimensions prevents the application in personal dosimetry. Recent research works reports the development of new detection devices based on photovoltaic PIN diodes, which were successfully employed for detecting and monitoring exposition to X rays. In this work, we step forward by coupling a 2mm anthracene scintillator NE1, which converts the high energy radiation in visible light, generating a Strong signal which allows dispensing the use of photomultipliers. A low gain high performance amplifier and a digital acquisition device are employed to measure instantaneous and cumulative doses for energies ranging from X rays to Gamma radiation up to 2 MeV. One of the most important features of the PIN diode relies in the fact that it can be employed as a detector for ionization radiation, since it requires a small energy amount for releasing electrons. Since the photodiode does not amplify the corresponding photon current, it must be coupled to a low gain amplifier. Therefore, the new sensor works as a scintillator coupled with a photodiode PIN. Preliminary experiments are being performed with this sensor, showing good results for a wide range of energy spectrum. (author)

  12. Investigation of the effect of temperature, dose rate and short-term post-irradiation change on the response of various types of dosimeters to cobalt-60 gamma radiation for quality assurance in Thailand

    International Nuclear Information System (INIS)

    Biramontri, S.

    2000-01-01

    The influences of combined effect of irradiation temperature from -80 deg. C to 60 deg. C and dose rate between 0.2 and 4 Gy/s on the gamma ray response of several commercial routine dosimeters (Harwell Red 4034, Gammachrome YR, FWT-60-00 radiochromic films, FWT-70-40 optical waveguides, GafChromic films, and Fuji CTA-FTR-125 films) were investigated for quality assurance in radiation processes. Besides, the studies of short term post-irradiation stability for the period of 2 h to 7 days are also presented. The overall results indicate the need for a calibration protocol under conditions of use. (author)

  13. Environmental gamma radiation levels around various DAE research centres

    International Nuclear Information System (INIS)

    Takale, R.A.; Swarnakar, M.; Shetty, P.G.; Sahu, S.K.; Pandit, G.G.

    2014-01-01

    This paper presents the gamma radiation levels of four research centres viz. Bhabha Atomic Research Centre (BARC), Trombay; Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam; Variable Energy Cyclotron Centre (VECC), Kolkata; Raja Ramanna Centre for Advanced Technology (RRCAT), Indore; and an industry Board of Radiation and Isotope Technology (BRIT), Vashi. BARC is India's premier nuclear research facility and is a multi-disciplinary research centre with extensive infrastructure for advanced research and development (R and D). IGCAR, Kalpakkam is engaged in scientific research and advanced engineering programme towards the development of Fast Breeder Reactor technology. VECC Kolkata is dedicated to carry out frontier R and D in the fields of Accelerator Science and Technology, Nuclear Science (Theoretical and Experimental), and Material Science etc. RRCAT, Indore has rapidly grown into a premier institute for R and D in lasers, accelerators and their applications. BRIT, Vashi unit is involved in production, development, and supply of radioisotope based products and provision of isotope applications, radiation processing, radio analytical services etc. With an objective to keep a watch on the prevailing environmental background gamma radiation level around all the DAE installations, routine monitoring programme are being carried out using the Thermo Luminescent Dosimeters (TLDs). TLDs provide the simple, inexpensive and precise measurement of small, integrated, external gamma radiation dose rate. The general practice of this programme is to observe the outdoor gamma radiation levels. This paper summarizes the methodology and gamma radiation levels of four research centres viz. BARC, IGCAR, VECC, RRCAT and an industry BRIT, Vashi

  14. The secondary biogenic radiation of gamma-irradiated human blood

    International Nuclear Information System (INIS)

    Kuzin, A.M.; Surkenova, G.N.; Budagovskij, A.V.; Gudi, G.A.

    1997-01-01

    The sample of blood freshly taken from healthy men were gamma-irradiated with a dose of 10 Gy. It was shown that after the treatment the blood gained the capacity to emit secondary biogenic radiation. Emission lasted for some hours, passed through quartz-glass curette and was revealed by stimulating influence on biological detector (sprouting seeds)

  15. Semiconductor dosimetry system for gamma and neutron radiation

    International Nuclear Information System (INIS)

    Savic, Z.; Pavlovic, Z.

    1995-01-01

    The semiconductor dosimetry system for gamma and neutron radiation based on pMOS transistor and PIN diode is described. It is intended for tactical or accidental personal dosimetry. The production steps are given. The temperature, dose and time (fading) response are reported. Hardware and software requirements which are needed for obtaining the desired measurement error are pointed. (author)

  16. Radiation doses in interventional neuroradiology

    International Nuclear Information System (INIS)

    Theodorakou, C.; Butler, P.; Horrocks, J.A.

    2001-01-01

    Patient radiation doses during interventional radiology (IR) procedures may reach the thresholds for radiation-induced skin and eye lens injuries. This study investigates the radiation doses received by patients undergoing cerebral embolization. Measurements were conducted using thermoluminescent dosimeters. Radiotherapy verification films were used in order to visualise the radiation field. For each procedure the fluoroscopic and digital dose-area product, the fluoroscopic time, the total number of acquired images and entrance-skin dose calculated by the angiographic unit were recorded. In this paper, the skin, eye and thyroid glands doses on a sample of patients are presented. From a preliminary study of 13 patients having undergone cerebral embolization, it was deduced that six of them have received a dose above 1 Gy. Detailed dose data from patients undergoing IR procedures will be collected in the future with the aim of developing a model to allow estimation of the dose prior to the procedure as well as to look at techniques of dose reduction. (author)

  17. Radiation dose during angiographic procedures

    International Nuclear Information System (INIS)

    Lavoie, Ch.; Rasuli, P.

    2001-01-01

    The use of angiographic procedures is becoming more prevalent as new techniques and equipment are developed. There have been concerns in the scientific community about the level of radiation doses received by patients, and indirectly by staff, during some of these radiological procedures. The purpose of this study was to assess the level of radiation dose from angiographic procedures to patient at the Ottawa Hospital, General Campus. Radiation dose measurements, using Thermo-Luminescent Dosimeters (TLDs), were performed on more than 100 patients on various procedures. The results show that while the patient dose from the great majority of angiographic procedures is less than 2 Gy, a significant number of procedures, especially interventional procedures may have doses greater than 2 Gy and may lead to deterministic effects. (author)

  18. Mapping the outdoor gamma dose rate in Indonesia

    International Nuclear Information System (INIS)

    Iskandar, Dadong; Syarbaini, Sutarman; Bunawas, Kusdiana

    2008-01-01

    Full text: Indonesia is the largest archipelago in the world, comprising five main islands - Java, Sumatra, Sulawesi, Kalimantan and Papua - as well as 30 archipelagoes totaling 17,508 islands with about 6000 of those inhabited. Mapping the outdoor gamma dose rate in Indonesia is a research project conducted by National Nuclear Energy Agency since 2005 aiming to produce a baseline data map as an overview for planning purposes. In these three years 4 main islands has been measured. The grid system has been used in the research. In Sumatra Island the grid is 50 x 50 km 2 , while in Java 40 x 40 km 2 , in Kalimantan 60 x 60 km 2 , and in Sulawesi 40 x 40 km 2 . The gamma dose rates have been measured by Mini Gamma Ray Spectrometer Model GR-130 made by Exploranium-Canada. Figure 1 shows the map of outdoor gamma dose rate in Indonesia. Range of dose rate are in Sumatra from 22,96 ± 0,46 n Sv/h to 186,08 ± 3,72 n Sv/h, in Java 11,32 ± 0,72 n Sv/h to 127,54 ± 6,14 n Sv/h, in Kalimantan 10.72 ± 8.32 n Sv/h to 349,48 ± 57,21 n Sv/h, and in Sulawesi 17.7 ± 11,5 n Sv/h to 467 ± 102 n Sv/h. The arithmetic and geometric mean of dose rate in Indonesia are 68 n Sv/h and 53 n Sv/h, respectively. In general, outdoor gamma dose rate in Indonesia is in a normal range. There are some regions have anomaly of gamma dose rate, for examples at North Sumatra 186.08 ± 3,72 n Sv/h (N 2.12727, E 99.80909), at West Kalimantan 349,48 ± 57,21 n Sv/h (S 1.39507, E 110.57584), at West Sulawesi 487 ± 103 n Sv/h (S 2.95781, E 118.86995), etc. These data is very useful as a radiation baseline in Indonesia. (author)

  19. Radiation. Doses, effect, risk

    International Nuclear Information System (INIS)

    Vapirev, E.; Todorov, P.

    1994-12-01

    This book outlines in a popular form the topic of ionizing radiation impacts on living organisms. It contains data gathered by ICRP for a period of 35 years. The essential dosimetry terms and units are presented. Natural and artificial sources of ionizing radiation are described. Possible biological radiation effects and diseases as a consequence of external and internal irradiation at normal and accidental conditions are considered. An assessment of genetic risk for human populations is presented and the concept of 'acceptable risk' is discussed

  20. Effect of low dose of gamma radiation on the induction and signalling of complex damages of DNA in the mammals cells

    International Nuclear Information System (INIS)

    Boucher, D.

    2006-09-01

    The work presented in the frame of this thesis are in line with the studies on the radioinduced damages of DNA in order to better understand their genotoxic effects and the associated risks. The different radioinduced damages of DNA are given, the complex damages, double strand-break and multiple damages are particularly detailed as well as their methods of detection. Are presented the systems implemented in the cell in order to point the radioinduced damages and to implement the repair systems of these lesions. Then, are presented the knowledge on the effects of low doses and low dose rates. The whole of this work has for objective to highlight the mechanisms by which the reduction of dose rate allows an increase of cell survival. By a better knowledge of the system implemented in response to a low dose rate irradiation, it is possible to valid or not the linear without threshold model of low doses effects and consequently to better understand the eventual risks of cancer linked to exposures of low doses of ionizing radiation. (N.C.)

  1. Response of radiation monitoring labels to gamma rays and electrons

    DEFF Research Database (Denmark)

    Rahim, F. Abdel; Miller, Arne; McLaughlin, W.L.

    1985-01-01

    or location has been irradiated to high doses. Among labels available worldwide, a few are suitable for indicating absorbed dose regions of slightly less than 104 Gy (monitoring high dose ranges (i.e., sterilization dose levels of > 104 Gy or > 1 Mrad), and in some cases......, and differences in dose rate and radiation type (gamma rays and electron beams) were made on 15 kinds of labels. The results show that, for many types of indicators, diverse effects may give misleading conclusions unless countermeasures are taken. For example, some of the most commonly used labels, which contain...... permit somewhat more precise discrimination of dose levels, and may sometimes be useful for monitoring differences in local dose distributions or area monitoring of radiation damage probabilities around particle accelerators or large radionuclide sources....

  2. Development of autonomous gamma dose logger for environmental monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Jisha, N. V.; Krishnakumar, D. N.; Surya Prakash, G.; Kumari, Anju; Baskaran, R.; Venkatraman, B. [Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu (India)

    2012-03-15

    Continuous monitoring and archiving of background radiation levels in and around the nuclear installation is essential and the data would be of immense use during analysis of any untoward incidents. A portable Geiger Muller detector based autonomous gamma dose logger (AGDL) for environmental monitoring is indigenously designed and developed. The system operations are controlled by microcontroller (AT89S52) and the main features of the system are software data acquisition, real time LCD display of radiation level, data archiving at removable compact flash card. The complete system operates on 12 V battery backed up by solar panel and hence the system is totally portable and ideal for field use. The system has been calibrated with Co-60 source (8.1 MBq) at various source-detector distances. The system is field tested and performance evaluation is carried out. This paper covers the design considerations of the hardware, software architecture of the system along with details of the front-end operation of the autonomous gamma dose logger and the data file formats. The data gathered during field testing and inter comparison with GammaTRACER are also presented in the paper. AGDL has shown excellent correlation with energy fluence monitor tuned to identify {sup 41}Ar, proving its utility for real-time plume tracking and source term estimation.

  3. Development of autonomous gamma dose logger for environmental monitoring.

    Science.gov (United States)

    Jisha, N V; Krishnakumar, D N; Surya Prakash, G; Kumari, Anju; Baskaran, R; Venkatraman, B

    2012-03-01

    Continuous monitoring and archiving of background radiation levels in and around the nuclear installation is essential and the data would be of immense use during analysis of any untoward incidents. A portable Geiger Muller detector based autonomous gamma dose logger (AGDL) for environmental monitoring is indigenously designed and developed. The system operations are controlled by microcontroller (AT89S52) and the main features of the system are software data acquisition, real time LCD display of radiation level, data archiving at removable compact flash card. The complete system operates on 12 V battery backed up by solar panel and hence the system is totally portable and ideal for field use. The system has been calibrated with Co-60 source (8.1 MBq) at various source-detector distances. The system is field tested and performance evaluation is carried out. This paper covers the design considerations of the hardware, software architecture of the system along with details of the front-end operation of the autonomous gamma dose logger and the data file formats. The data gathered during field testing and inter comparison with GammaTRACER are also presented in the paper. AGDL has shown excellent correlation with energy fluence monitor tuned to identify (41)Ar, proving its utility for real-time plume tracking and source term estimation.

  4. Effects of a Low Dose of Gamma Radiation on the Morphology, and the Optical and the Electrical Properties of an ITO Thin Film as an Electrode for Solar Cell Applications

    Science.gov (United States)

    Kakil, Shaida Anwer; Sabr, Barzan Nehmat; Hana, Lary Slewa; Abbas, Tariq Abdul-Hameed; Hussin, Sarwin Yaseen

    2018-03-01

    The present study focuses on the influence of gamma irradiation induced through the morphology effects on the modification of the optical and the electrical properties of transparent indium tin oxide (ITO) thin films. The prepared samples were exposed to low gamma radiation at room temperature with doses 3.90 Gy, 7.81Gy, 11.7 Gy, and 15.62 Gy from a Cs-137 radioisotope source. The surface structures before and after irradiation were analyzed. Atomic force microscopy was performed on two samples, one before and one after irradiation, to investigate any change in the morphology. The roughness parameters, such as S z , S v , S c , and S q , were found for the surface of the porous films after the gamma irradiation. As the dose of the irradiation was increased, the light absorption of the films increased, and the value of the optical energy gap changed from 3.83 to 3.73 eV while the refractive index changed from 1.9 to 2.05, as determined by using the Swanipol method. Electrical properties, such as the electrical sheet resistance, contact resistance, and current transfer length, were measured by using the four-point probe and the transmission line method (TLM). The determined electrical sheet resistance, contact resistance, and current transfer length were 14.54 Ω, 0.235 Ω, and 0.04 mm before gamma irradiation and 17.61 Ω, 0.1316 Ω, and 0.0025 mm after gamma irradiation. The decrease in the value of the contact resistance due to the irradiation led to a decrease in the current loss while the increase in the sheet resistance will cause the loss of some current through the film.

  5. Cosmical sources of gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kuchowicz, B [Warsaw Univ. (Poland)

    1974-01-01

    A brief historical outline of the X-ray and ..gamma..-ray astronomies is given first, then a summary of the recent status of X-ray astronomy follows. Further chapters include information on ..gamma..-ray sources in the solar system, in our Galaxy, and beyond it. In discussing linear gamma spectra attention is paid to the possibility of studying explosive nucleo-synthesis by observation of gamma lines from supernova remnants, etc. Questions of the isotropic gamma background are discussed at the end of the survey.

  6. Effect of potato plants grown from tubers irradiated with low doses of gamma radiation on feeding and reproductive behaviours of potato tuber moth Phtorimaea Operculella (Lep., Gelechiidae)

    International Nuclear Information System (INIS)

    Saour, G.; Makee, H.; Al-Oudat, M.

    1997-09-01

    The feeding behavior of potato tuber moth Phthorimaea Operculella (Lep., Gelechiidae) larvae reared on leaves and tubers of potato plants, which its seeds had been irradiated with low doses of gamma irradiation (1, 3, 5, 10, Gy) has been studied. Significant differences in the larval developmental time, pupae developmental time, pupae weight, mortality, fecundity and percentage of egg hatch, was observed between insects fed on plants grown from the irradiated seeds and the control. It appears that leaves of potato plants grown from the irradiated seeds, particularly those of 3 Gy, became more favourable for the larvae, whilst the resulted tubers, except tubers of the dose of 10 Gy, which could have repellent properties became more resistant to potato tuber moth. Plant development stage and tubers storage at ambient temperatures condition affect the degree of sensitivity of the larvae. Leaves and tubers of 10 Gy irradiated seeds became more suitable for insect development, indicating that the later dose may inhibit the production of secondary plant metabolites chemical compounds. (author)

  7. Degradation study of Durolon polycarbonate submitted to gamma radiation

    International Nuclear Information System (INIS)

    Miranda, A.; Sciani, V.

    1992-01-01

    The effect of gamma radiation from a cobalt 60 source in the 27000 Durolon polycarbonate irradiated with doses between 0,2 and 1000 kGy at 25 0 C was analyzed. For this reason the samples was submitted to the mechanical assay of tension, deformation and hardness and optical assay of transmittance. The obtained results show a good mechanical stability of the polycarbonate, when it was submitted to gamma irradiation in doses up to 20 kGy. (C.G.C.). 05 refs., 04 figs

  8. Sterilization of spices and vegetable seasoning by gamma radiation

    International Nuclear Information System (INIS)

    Lescano, G.; Narvaiz, P.; Kairiyama, E.

    1991-01-01

    Ginger, turmeric, Cayenne pepper, onion and garlic powders were gamma irradiated with doses of 10 and 30 kGy, and stored at room temperature for six months. Microbiological, chemical and sensory analyses were performed. Samples were sterilized with 30 kGy. The pH values of water extracts of these condiments appear practically unchanged by the applied gamma radiation doses. Spectrophotometric analysis of methyl alcohol extracted of the pigments showed no irradiation effect in turmeric and ginger. Seasoning capacity (odour, flavour and pungency) were not altered by 30 kGy irradiation. (author) 24 refs.; 2 figs.; 4 tabs

  9. Gamma radiation effects on different sorts of onions

    International Nuclear Information System (INIS)

    Burov, B.A.

    1977-01-01

    Gamma radiation effects on different sorts of onions were studied to improve ways of obtaining agricultural vegetation mutations and to find out the genotype role in induced mutagenesis. It is established that rhizome onion seeds are more radiosensitive than bulbous ones, ephemeroide form seeds are most stable among bulbous plants. Table data on dependence of seed germination and plant survival on radiation dose are presented

  10. Research of pulse gamma ray radiation effect on microcontroller system

    International Nuclear Information System (INIS)

    Yang Shanchao; Ma Qiang; Jin Xiaoming; Li Ruibin; Lin Dongsheng; Chen Wei; Liu Yan

    2012-01-01

    An experimental result of power chip LM7805 and microcontroller EE80C196KC20 based on the EE80C196KC20 testing system was presented. The pulse gamma ray radiation effect was investigated using 'Qiangguang-Ⅰ' accelerator. Latchup threshold of the microcontroller was obtained, and the relationship of supply current and I/O output with the transient dose rate was observed. The result shows that the restrainability of power chip on pulse gamma ray radiation induces microcontroller latchup effect. (authors)

  11. Disinfection of sewage water and sludge using gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Musaad, R M.A. [Department of Radiation Chemistry, Atomic Energy Research Coordination Council, Sudan Academy of Sciences, Khartoum (Sudan)

    2008-04-15

    This study has been carried out to assess the efficiency of gamma radiation in disinfecting sewage water and sludge from harmful pathogenic bacteria (e.g. Streptococcus, Salmonella, Shigella, total E-coli and total coliform), parasites (Ascaris ova) as well as its ability to degrade organic matter (BOD). Samples were exposed to gamma-radiation doses ranging from 0.5 to 8 KGy using Co''6{sup 0} cell. Amongst pathogenic bacteria which are subjected to different doses of gamma-radiation Streptococcus faecalis revealed to be the most resistance bacterial indicator since complete elimination of these bacteria could be attained at 3.5 KGy. While total e-coli shown to be the most sensitive with lethal dose at 2 KGy. The radiation doses that required for reducing the bacterial population by 90% (D{sub 10}) and 50% (D {sub 50}) were determined for each species. The D{sub 10} values found ranged from 0.75 KGy for Streptococcus and 2.75 KGy for total count bacteria. On the other hand, D{sub 50} fall within the range of 0.5 KGy for total count bacteria, total coliform and Streptococcus, and 1.0 KGy for total e-coli. With regard to the efficiency of radiation treatment to destroy Ascaris ova viability it was found that no larvae were viable after exposure to 1.0 KGy following incubation of exposed ova for four weeks period.(Author)

  12. Disinfection of sewage water and sludge using gamma radiation

    International Nuclear Information System (INIS)

    Musaad, R.M.A.

    2008-04-01

    This study has been carried out to assess the efficiency of gamma radiation in disinfecting sewage water and sludge from harmful pathogenic bacteria (e.g. Streptococcus, Salmonella, Shigella, total E-coli and total coliform), parasites (Ascaris ova) as well as its ability to degrade organic matter (BOD). Samples were exposed to gamma-radiation doses ranging from 0.5 to 8 KGy using Co''6 0 cell. Amongst pathogenic bacteria which are subjected to different doses of gamma-radiation Streptococcus faecalis revealed to be the most resistance bacterial indicator since complete elimination of these bacteria could be attained at 3.5 KGy. While total e-coli shown to be the most sensitive with lethal dose at 2 KGy. The radiation doses that required for reducing the bacterial population by 90% (D 10 ) and 50% (D 50 ) were determined for each species. The D 10 values found ranged from 0.75 KGy for Streptococcus and 2.75 KGy for total count bacteria. On the other hand, D 50 fall within the range of 0.5 KGy for total count bacteria, total coliform and Streptococcus, and 1.0 KGy for total e-coli. With regard to the efficiency of radiation treatment to destroy Ascaris ova viability it was found that no larvae were viable after exposure to 1.0 KGy following incubation of exposed ova for four weeks period.(Author)

  13. Effect of. gamma. radiation in relatively low dose on the activity of glutaminase in subcellular fraction of brain and liver cells. [Rats

    Energy Technology Data Exchange (ETDEWEB)

    Tkach, V M

    1973-01-01

    The effect of ..gamma..-irradiation at a dose of 40 rads was studied on the exchange of glutamine in rats. It has been shown that the irradiation leads to a significant lowering of the activity of glutaminamidohydrolase (I) in brain mitochondria and in the liver after 1, 3, 7, 15, and 30 days post exposure. In the fractions containing nuclei, fraction of myofibrillae and connective tissue, a slow down of the deamidation of glutamine also takes place, and only after 7 days the ammonium separation from glutamine increases and returns to normal. At the 15 and 30 days a second wave of the lower rate of the activity of I takes place. The type of the changes of I is the same in both organs, but in the liver it is expressed to a lesser degree. (JPRS)

  14. Resposta de sementes de amendoim a diferentes doses de radiação gama (60Co Response of peanut seeds to different levels of gamma radiation (60Co

    Directory of Open Access Journals (Sweden)

    Tatiana da S. Santos

    2010-10-01

    Full Text Available A radiação gama, proveniente da fonte de 60Co, é bastante utilizada para esterilização, visando a prevenção da decomposição e a toxidez de origem microbiana em diversos produtos. O grau de radiossensibilidade de um embrião vegetal depende da espécie, do estágio de seu desenvolvimento durante a radiação, da dose empregada e do critério usado para medir o efeito biológico, sendo comumente utilizado o teste de germinação. Objetivou-se, com este trabalho, estudar a sensibilidade do amendoim a radiação gama e seus efeitos na germinação, no vigor e na micoflora das sementes da cultivar BRS Havana, irradiadas com uma fonte de 60Co, tipo gammacell, com taxa de dosagem de 12,5 kGy h-1. As doses testadas em kGy foram as seguintes: 0; 0,5; 1,0; 1,5; 2,0; 2,5; 3,0; 6,0; 9,0; 12,0; 15,0; 18,0; 21,0 e 24,0. Com os resultados obtidos, concluiu-se que as doses acima de 3,0 kGy prejudicaram a viabilidade das sementes e as doses acima de 12 kGy comprometeram totalmente o vigor e a germinação das sementes de amendoim. A radiação a partir da dose 2,0 kGy eliminou os fungos Aspergillus flavus e Aspergillus niger e, a partir da dose 3,0 kGy, eliminou o Aspergillus glaucus. O Penicilium spp. permaneceu em mais de 30% das sementes em todos os tratamentos com radiação, não sendo eliminado até a dose de 24 kGy.The gamma radiation from 60Co source is widely used for sterilization aiming at preventing decomposition and toxicity from microbes in several products. The degree of radiosensitvity of a plant embryo depends on the species, the development stage during radiation, doses used and the criteria used to measure the biological effect, the germination test, being commonly used.This work aimed to study the peanut sensitivity to gamma radiation and its effects in the germination, in the vigour and seeds microflora of cultivar BRS Havana, irradiated with 60Co source, type gammacell with rate of dosage of 12.5 kGy h-1. The tested doses were the

  15. Residual water treatment for gamma radiation. Tratamiento de aguas residuales por radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, L [Universidad Nacional Mayor de San Marcos. Facultad de Quimica (Peru)

    1990-07-01

    The treatment of residual water by means of gamma radiation for its use in agricultural irrigation is evaluated. Measurements of physical, chemical, biological and microbiological contamination indicators were performed. For that, samples from the treatment center of residual water of San Juan de Miraflores were irradiated up to a 52.5 kGy dose. The study concludes that gamma radiation is effective to remove parasites and bacteria, but not for removal of the organic and inorganic matter. (author). 15 refs., 3 tabs., 4 figs.

  16. 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)

  17. Radiation dose estimates for radiopharmaceuticals

    International Nuclear Information System (INIS)

    Stabin, M.G.; Stubbs, J.B.; Toohey, R.E.

    1996-04-01

    Tables of radiation dose estimates based on the Cristy-Eckerman adult male phantom are provided for a number of radiopharmaceuticals commonly used in nuclear medicine. Radiation dose estimates are listed for all major source organs, and several other organs of interest. The dose estimates were calculated using the MIRD Technique as implemented in the MIRDOSE3 computer code, developed by the Oak Ridge Institute for Science and Education, Radiation Internal Dose Information Center. In this code, residence times for source organs are used with decay data from the MIRD Radionuclide Data and Decay Schemes to produce estimates of radiation dose to organs of standardized phantoms representing individuals of different ages. The adult male phantom of the Cristy-Eckerman phantom series is different from the MIRD 5, or Reference Man phantom in several aspects, the most important of which is the difference in the masses and absorbed fractions for the active (red) marrow. The absorbed fractions for flow energy photons striking the marrow are also different. Other minor differences exist, but are not likely to significantly affect dose estimates calculated with the two phantoms. Assumptions which support each of the dose estimates appears at the bottom of the table of estimates for a given radiopharmaceutical. In most cases, the model kinetics or organ residence times are explicitly given. The results presented here can easily be extended to include other radiopharmaceuticals or phantoms

  18. Effects of small radiation doses

    International Nuclear Information System (INIS)

    Fuchs, G.

    1986-01-01

    The term 'small radiation dosis' means doses of about (1 rem), fractions of one rem as well as doses of a few rem. Doses like these are encountered in various practical fields, e.g. in X-ray diagnosis, in the environment and in radiation protection rules. The knowledge about small doses is derived from the same two forces, on which the radiobiology of human beings nearly is based: interpretation of the Hiroshima and Nagasaki data, as well as the experience from radiotherapy. Careful interpretation of Hiroshima dates do not provide any evidence that small doses can induce cancer, fetal malformations or genetic damage. Yet in radiotherapy of various diseases, e.g. inflammations, doses of about 1 Gy (100 rad) do no harm to the patients. According to a widespread hypothesis even very small doses may induce some types of radiation damage ('no threshold'). Nevertheless an alternative view is justified. At present no decision can be made between these two alternatives, but the usefullness of radiology is definitely better established than any damage calculated by theories or extrapolations. Based on experience any exaggerated fear of radiations can be met. (author)

  19. Gamma Radiation Assessment In Kartini Reactor And Its Vicinity

    International Nuclear Information System (INIS)

    Yazid, M.; Supriyatni, E.; Maryono; Bastianudin, Aris

    2000-01-01

    Measurement to calculate dose assesment for gamma radiation in Kartini Reactor and its vicinity has been done whether on operated or un operated condition. Measurement was performed using height pressured ionization chamber, Reuther Stokes RS-112 production. Measurement location was determined based on distance variation inwardly and outwardly of reactor building and its vicinity. The result showed that the average dose rate in the reactor building when un operated is in the range of 11.4-38.6 mu rad/hour and when the reactor operated is 166.4-1910.9 mu rad/hour. While the vicinity of the reactor on operated condition the average dose rate is 34.4-38.6 mu rad/hour in un operated condition is 6.9-7.0 mu rad/hour. This result showed that the reactor operated did not rise the radiation exposure level in its vicinity. From the personnel assesment dose rate of gamma radiation is 28.54 mrem/week on operated condition, 0.90 mrem.week on un operated condition. While dose rate outside the reactor is 0.44 and 0.27 mrem/week for operated and un operated condition consecutively. This dose rate is still below maximum permissible dose than recommended by the national regulation of radiation protection from BAPETEN No. 01/Ka.BAPETEN/V-99

  20. Use of thermoluminescent dosimetry in gamma radiation fields studies

    International Nuclear Information System (INIS)

    Carron, W.

    1987-01-01

    The depth-dose curves for gamma rays in material of interest to agronomy were obtained using lithium fluoride thermoluminescent dosimeters. The dose conversion factors for LiF were determined from curves of the absorved dose versus depth in water, wood and soil. Mathematics equations were chosen to best fit these curves. In the view of the results we came to the conclusion that in the studied materials the absorved radiation dose presents a great variation to the depth and could be correlated through of the exponential regression. (author)

  1. Radiation apparatus with distance mapper for dose control

    International Nuclear Information System (INIS)

    Saunders, A.M.

    1990-01-01

    The patent describes apparatus for delivering a radiation dose. It comprises: radiation source means for producing a beam of ionizing gamma ray or x-ray radiation directed so as to deliver a dose of the radiation to an area of a target surface, a light source emitting a light beam in a direction transverse to the direction of the ionizing radiation beam, a photodetector, positioned to receive light scattered from the target surface, means for scanning the light beam over the area of the target surface, means for forming a three-dimensional surface profile map of the area of the target surface without movement of the radiation source means or the light source, and means responsive to the surface profile map for adjusting the dose of radiation from the radiation source over the area of the target surface, so that the radiation source means and the light source may be operated simultaneously

  2. Radiation absorbed doses in cephalography

    International Nuclear Information System (INIS)

    Eliasson, S.; Julin, P.; Richter, S.; Stenstroem, B.

    1984-01-01

    Radiation absorbed doses to different organs in the head and neck region in lateral (LAT) and postero-anterior (PA) cephalography were investigated. The doses were measured by thermoluminescence dosimeters (TLD) on a tissue equivalent phantom head. Lanthanide screens in speed group 4 were used at 90 and 85 k Vp. A near-focus aluminium dodger was used and the radiation beam was collimated strictly to the face. The maximum entrance dose from LAT was 0.25 mGy and 0.42 mGy from a PA exposure. The doses to the salivary glands ranged between 0.2 and 0.02 mGy at LAT and between 0.15 and 0.04 mGy at PA exposures. The average thyroid gland dose without any shielding was 0.11 mGy (LAT) and 0.06 mGy (PA). When a dodger was used the dose was reduced to 0.07 mGy (LAT). If the thyroid gland was sheilded off, the dose was further reduced to 0.01 mGy and if the thyroid region was collimated out of the primary radiation field the dose was reduced to only 0.005 mGy. (authors)

  3. Effect of gamma radiation on honey quality control

    International Nuclear Information System (INIS)

    Bera, A.; Almeida-Muradian, L.B.; Sabato, S.F.

    2009-01-01

    Honey is one of the most complex substances produced by bees, mainly from the nectar of flowers. Gamma radiation is a technique that can be used to decrease the number of microbiological problems associated with food and increase the shelf life of certain products. The objective of this study was to verify the effect of gamma radiation with source of cobalto-60 (10 kGy) on some parameters used in honey quality control. Seven samples of pure honey were obtained from local markets in Sao Paulo, Brazil, in 2007. The methods used are in accordance with Brazilian Regulations. The physicochemical parameters analyzed were: moisture, HMF, free acidity, pH, sugars and ash. The results showed that gamma radiation, in the dose mentioned above, did not cause significant physicochemical alterations.

  4. Effect of gamma radiation on honey quality control

    Energy Technology Data Exchange (ETDEWEB)

    Bera, A. [Radiation Technology Center, IPEN-CNEN/SP, A. Lineu Prestes, 2242, 05508-000 Sao Paulo (Brazil)], E-mail: berale@usp.br; Almeida-Muradian, L.B. [Av. Prof. Lineu Prestes, 580-Cidade Universitaria, Sao Paulo (Brazil); Sabato, S.F. [Radiation Technology Center, IPEN-CNEN/SP, A. Lineu Prestes, 2242, 05508-000 Sao Paulo (Brazil)], E-mail: sfsabato@ipen.br

    2009-07-15

    Honey is one of the most complex substances produced by bees, mainly from the nectar of flowers. Gamma radiation is a technique that can be used to decrease the number of microbiological problems associated with food and increase the shelf life of certain products. The objective of this study was to verify the effect of gamma radiation with source of cobalto-60 (10 kGy) on some parameters used in honey quality control. Seven samples of pure honey were obtained from local markets in Sao Paulo, Brazil, in 2007. The methods used are in accordance with Brazilian Regulations. The physicochemical parameters analyzed were: moisture, HMF, free acidity, pH, sugars and ash. The results showed that gamma radiation, in the dose mentioned above, did not cause significant physicochemical alterations.

  5. Gamma ray doses proceeding from natural occurring radionuclides in closed environments

    International Nuclear Information System (INIS)

    Aguiar, Vitor Angelo P. de; Medina, Nilberto H.; Silveira, Marcilei A. Guazzelli da; Moreira, Ramon H.

    2009-01-01

    In this work we report on the application of gamma-ray spectrometry in the study of the effective dose coming from terrestrial natural elements present in building materials such as sand, cement, lime (CaO) and milled granitic stones. The major contribution to annual gamma-ray radiation effective dose is due to the natural occurring radionuclides 40 K, 232 Th and 238 U. Two spectrometry systems were employed to measure the gamma radiation: one with a 60% efficient GeHP detector and the second one with a 2''x2'' NaI(Tl) scintillator. The estimated effective dose coming from the three reference rooms assumed is 0.63 mSv/yr, proceeding from terrestrial natural elements. The principal gamma radiation sources are cement, sand and bricks. (author)

  6. Radiation dose rate measuring device

    International Nuclear Information System (INIS)

    Sorber, R.

    1987-01-01

    A portable device is described for in-field usage for measuring the dose rate of an ambient beta radiation field, comprising: a housing, substantially impervious to beta radiation, defining an ionization chamber and having an opening into the ionization chamber; beta radiation pervious electrically-conductive window means covering the opening and entrapping, within the ionization chamber, a quantity of gaseous molecules adapted to ionize upon impact with beta radiation particles; electrode means disposed within the ionization chamber and having a generally shallow concave surface terminating in a generally annular rim disposed at a substantially close spacing to the window means. It is configured to substantially conform to the window means to define a known beta radiation sensitive volume generally between the window means and the concave surface of the electrode means. The concave surface is effective to substantially fully expose the beta radiation sensitive volume to the radiation field over substantially the full ambient area faced by the window means

  7. Development of a dose simulation software for gamma irradiation systems

    International Nuclear Information System (INIS)

    Omi, Nelson Minoru

    2000-01-01

    The use of high temperature, thermal and chemical treatment are among the used sterilization process of food and many products. The ionizing radiation came as another option, it has being used for many purposes and it became available due to the technological development in the second half of the 20 th century. Together with sterilization, many uses of the ionizing radiation were developed, such as applications on health, industrial products and waste recycling, food irradiation, vulcanizing, polymerization and gems color enhancing. The 60 Co gamma stands out among the used radiation sources on commercial facilities. lt is used to optimize this process with many dose mapping tests. The objective of this work is to develop a software to simulate the doses in 60 Co gamma irradiation systems. lt can be used to optimize a process on the project stage of a facility and to make viability studies for new applications in installations already set up. The validation of this software was done comparing the simulation results with the dosimetry data of an operating irradiation plant. The flexibility of the software was verified with extra dosimetry tests performed in another sterilization facility. (author)

  8. Radiation dose rate meter

    International Nuclear Information System (INIS)

    Kronenberg, S.; Siebentritt, C.R.

    1981-01-01

    A combined dose rate meter and charger unit therefor which does not require the use of batteries but on the other hand produces a charging potential by means of a piezoelectric cylinder which is struck by a manually triggered hammer mechanism. A tubular type electrometer is mounted in a portable housing which additionally includes a geiger-muller (Gm) counter tube and electronic circuitry coupled to the electrometer for providing multi-mode operation. In one mode of operation, an rc circuit of predetermined time constant is connected to a storage capacitor which serves as a timed power source for the gm tube, providing a measurement in terms of dose rate which is indicated by the electrometer. In another mode, the electrometer indicates individual counts

  9. Radiation doses and possible radiation effects of low-level, chronic radiation in vegetation

    International Nuclear Information System (INIS)

    Rhoads, W.A.; Franks, L.A.

    1975-01-01

    Measurements were made of radiation doses in soil and vegetation in Pu-contaminated areas at the Nevada Test Site with the objective of investigating low-level, low-energy gamma radiation (with some beta radiation) effects at the cytological or morphological level in native shrubs. In this preliminary investigation, the exposure doses to shrubs at the approximate height of stem apical meristems were estimated from 35 to 140 R for a ten-year period. The gamma exposure dose estimated for the same period was 20.7 percent +- 6.4 percent of that recorded by the dosimeters used in several kinds of field instrument surveys. Hence, a survey instrument reading made at about 25 cm in the tops of shrubs should indicate about 1 / 5 the dosimeter-measured exposures. No cytology has yet been undertaken because of the drought since last winter. (auth)

  10. 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)

  11. Radiation risk factors and dose limits

    International Nuclear Information System (INIS)

    Barendsen, G.W.

    1979-01-01

    The contents of the ICRP publications 9 (1965) and 26 (1977) are outlined and the research conducted during these years considered. Expressions are derived for the frequency for induction of cancer from the most common irradiations - X rays, gamma rays and electrons. The dose limits advised by the ICRP are discussed and the first two fundamental principles are presented - that no one should be subjected to radiation without useful cause and that in those cases where irradiation is thought necessary, the medical, scientific, social and economic advantages need to be carefully considered with respect to the possible disadvantages. (C.F.)

  12. Sterilization of the melon fly, Dacus cucurbitae Coquillett (Diptera: Tephritidae), with gamma-radiation: Effect of dose on oviposition behavior of irradiated females

    International Nuclear Information System (INIS)

    Teruya, T.

    1990-01-01

    In a laboratory condition, the visiting and the puncturing frequencies of gamma-irradiated Dacus cucurbitae females on cucumber Cucumis sativus fruits were examined. In the non-irradiated females, the frequencies reached equilibrium ca. 1 week after adult emergence. The frequencies of the irradrated females decreased with irradiation dosage, but gradually resumed frequency with age. A similar trend was found in the relationship between the irradiation dose and the rates of the puncturing frequency to the visiting frequency. As the irradiation dose increased, the rate of under-developed ovaries increased. The ratio of cumulative puncturing frequency in the 70 Gy irradiated (completely sterile) females to that of the non-irradiated females was estimated as 1/200 when daily survival rate in the field was assumed to be 0.85. The completely sterile adult females (40 days old) made punctures on all sizes of cucumber cultivated in a greenhouse. However, these punctures do not significantly damage the fruit. The sting of the sterile melon fly would not be a serious problem in eradication programs based on the Sterile Insect Technique

  13. Effect of low dose gamma radiation on stamen-hairs of different clones of Tradescantia presenting variability in the frequency of spontaneous mutations

    International Nuclear Information System (INIS)

    Takahashi, C.S.

    1976-01-01

    Changes in the frequency of spontaneous somatic mutations were studied for three different clones of Tradescantia heterozygotes for flower and stamen-hair color keeping them under controlled or natural conditions in order to verify the effect of different environmental conditions on the different genotypes. The effect of inflorescence age on the variation of spontaneous mutations was studied choosing young and old inflorescences of a same plant. Low dose irradiation experiments were carried out with those clones to elucidate the radiation effects on the clones presenting changes in the frequency of spontaneous mutations. The chronic-and acute irradiation effects of low dose irradiation of the stamen-hair of Tradescantia were also studied. Results are discussed. (M.A.) [pt

  14. Neutron and gamma dose and spectra measurements on the Little Boy replica

    International Nuclear Information System (INIS)

    Hoots, S.; Wadsworth, D.

    1984-01-01

    The radiation-measurement team of the Weapons Engineering Division at Lawrence Livermore National Laboratory (LLNL) measured neutron and gamma dose and spectra on the Little Boy replica at Los Alamos National Laboratory (LANL) in April 1983. This assembly is a replica of the gun-type atomic bomb exploded over Hiroshima in 1945. These measurements support the National Academy of Sciences Program to reassess the radiation doses due to atomic bomb explosions in Japan. Specifically, the following types of information were important: neutron spectra as a function of geometry, gamma to neutron dose ratios out to 1.5 km, and neutron attenuation in the atmosphere. We measured neutron and gamma dose/fission from close-in to a kilometer out, and neutron and gamma spectra at 90 and 30 0 close-in. This paper describes these measurements and the results. 12 references, 13 figures, 5 tables

  15. Effect of gamma radiation on growth, productivity and protein content of Chlorella Pyrenoidosa; Efecto de la radiacion gamma sobre el crecimiento, productividad y contenido proteico de Chlorella Pyrenoidosa

    Energy Technology Data Exchange (ETDEWEB)

    Martin, C; Fernandez, J

    1983-07-01

    The effect of five doses of gamma radiation: 10, 100, 500, 1000 and 5000 Gy at a dose rate of 4.500 Gy/h on growth, productivity and protein content of Chlorella pyroneidosa has been studied. High doses of gamma radiation have been observed to inhibit cellular division of Chlorella pyrenoidosa. Culture growth stopped 48 hours after irradiation at 5.000 Gy and 72 hours after irradiation at 500 and 1000 Gy. The lowest dose (10 Gy) produced a little growth stimulation that not statistically significative. Protein and aminoacid content did not show any change for gamma radiation doses studied. (Author) 32 refs.

  16. Spiral CT and radiation dose

    International Nuclear Information System (INIS)

    Imhof, H.; Schibany, N.; Ba-Ssalamah, A.; Czerny, C.; Hojreh, A.; Kainberger, F.; Krestan, C.; Kudler, H.; Noebauer, I.; Nowotny, R.

    2003-01-01

    Recent studies in the USA and Europe state that computed tomography (CT) scans compromise only 3-5% of all radiological exams, but they contribute 35-45% of total radiation dose to the patient population. These studies lead to concern by several public authorities. Basis of CT-dose measurements is the computed tomography dose index (CTDI), which was established 1981. Nowadays there are several modifications of the CTDI values, which may lead to confusion. It is suggested to use the standardized CTDI-100 w. value together with the dose length product in all CT-examinations. These values should be printed on all CT-images and allows an evaluation of the individualized patient dose. Nowadays, radiologist's aim must be to work at the lowest maximal diagnostic acceptable signal to noise ratio. To decrease radiation dose radiologist should use low kV and mA, but high pitches. Newly developed CT-dose-reduction soft-wares and filters should be installed in all CT-machines. We should critically compare the average dose used for a specific examination with the reference dose used in this country and/or Europe. Greater differences should caution the radiologist. Finally, we as radiologists must check very carefully all indications and recommend alternative imaging methods. But we have also to teach our customers--patients and medical doctors who are non-radiologists--that a 'good' image is not that which show all possible information, but that which visualize 'only' the diagnostic necessary information

  17. Evaluation of dose distributions in gamma chamber using glass plate detector

    Directory of Open Access Journals (Sweden)

    Narayan Pradeep

    2008-01-01

    Full Text Available A commercial glass plate of thickness 1.75 mm has been utilized for evaluation of dose distributions inside the irradiation volume of gamma chamber using optical densitometry technique. The glass plate showed linear response in the dose range 0.10 Kilo Gray (kGy to 10 kGy of cobalt-60 gamma radiation with optical sensitivity 0.04 Optical Density (OD /kGy. The change in the optical density at each identified spatial dose matrix on the glass plate in relation to the position in the irradiation volume has been presented as dose distributions inside the gamma chamber. The optical density changes have been graphically plotted in the form of surface diagram of color washes for different percentage dose rate levels as isodose distributions in gamma chamber. The variation in dose distribution inside the gamma chamber unit, GC 900, BRIT India make, using this technique has been observed within ± 15%. This technique can be used for routine quality assurances and dose distribution validation of any gamma chamber during commissioning and source replacement. The application of commercial glass plate for dose mapping in gamma chambers has been found very promising due to its wider dose linearity, quick measurement, and lesser expertise requirement in application of the technique.

  18. Study of the gamma radiation of ionium

    Energy Technology Data Exchange (ETDEWEB)

    Curie, I

    1949-12-01

    A Geiger counter study has been made of the ..gamma.. radiation of ionium. Eleven quanta of the L radiation of radium were observed for every hundred ..cap alpha.. disintegrations, and three ..gamma.. rays were found with energies of 68, 140, and 240 keV at a rate of 0.85, 0.33, 0.05 quanta, respectively, for 100 disintegrations. It is noted that the radiation spectrum of ionium as a whole is difficult to interpret. In the course of this work, the author calculated the efficiency of a thin-walled aluminum counter, both for the L radiation of radium and for ..gamma.. rays of 68 keV. The author also measured, for soft radiation, the ratio between the efficiency of a thin-walled aluminum counter and that of a similar counter lined with 0.11 mm of lead.

  19. Gamma radiation in pest control at the storehouses

    International Nuclear Information System (INIS)

    Tsvetkov, D.; Atanasov, Khr.; Berberov, D.

    1974-01-01

    The prospects of radiation control of wheat grain pests in Bulgaria are shown, drawing the following main conclusions: The lethal doses of gamma rays for the granary weevil, grain borer and confused flour beetle are fairly high - of the order of 300,000-400,000 r; the sterilizing doses of gamma rays arrest the reproduction of granary and rice weevils as well as of confused flour beetles. The irradiated insects, however, retain their sex activity and so may inhibit the reproduction of fertile populations. Irradiation strongly reduces the life span of, and consequently the damage done by, the insects; radiation control of stored-grain pests by using sterilizing doses does not deteriorate the technological quality of the wheat grain. (E.T.)

  20. Characterization of crumb rubber modified by gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Faldini, Sonia B.; Terence, Mauro C.; Miranda, Leila F.; Munhoz, Antonio H.; Domingues, Leandro S.; Coghetto, Gregory, E-mail: sfaldini@yahoo.com.br, E-mail: mauroterence@yahoo.com.br [Universidade Presbiteriana Mackenzie (UPM), Sao Paulo, SP (Brazil). Escola de Engenharia. Engenharia de Materiais

    2013-07-01

    The use of crumb rubber from scrap tires has become a common practice in the construction of roads, leading to improved properties of the asphalt and decreasing the environmental pollution. In this study, crumb rubber was modified by gamma radiation to eventually incorporate it into the asphalt and verify potential improvements of their properties. The crumb rubber modified by gamma radiation in the dose 500 kGy and 1000kGy was characterized by thermal analysis, infrared spectroscopy and scanning electron microscopy. The dose of radiation used has no effect on degradation temperatures. It is observed that the IV spectra of untreated rubbers and rubbers irradiated have substantially the same profile. The results indicate that despite small morphological changes in the irradiated rubber, they do not influence its degradation temperature and composition. (author)

  1. Characterization of crumb rubber modified by gamma radiation

    International Nuclear Information System (INIS)

    Faldini, Sonia B.; Terence, Mauro C.; Miranda, Leila F.; Munhoz, Antonio H.; Domingues, Leandro S.; Coghetto, Gregory

    2013-01-01

    The use of crumb rubber from scrap tires has become a common practice in the construction of roads, leading to improved properties of the asphalt and decreasing the environmental pollution. In this study, crumb rubber was modified by gamma radiation to eventually incorporate it into the asphalt and verify potential improvements of their properties. The crumb rubber modified by gamma radiation in the dose 500 kGy and 1000kGy was characterized by thermal analysis, infrared spectroscopy and scanning electron microscopy. The dose of radiation used has no effect on degradation temperatures. It is observed that the IV spectra of untreated rubbers and rubbers irradiated have substantially the same profile. The results indicate that despite small morphological changes in the irradiated rubber, they do not influence its degradation temperature and composition. (author)

  2. Atmospheric radiation flight dose rates

    Science.gov (United States)

    Tobiska, W. K.

    2015-12-01

    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. Space Environment Technologies (SET) has been conducting space weather observations of the atmospheric radiation environment at aviation altitudes that will eventually be transitioned into air traffic management operations. The Automated Radiation Measurements for Aerospace Safety (ARMAS) system and Upper-atmospheric Space and Earth Weather eXperiment (USEWX) both are providing dose rate measurements. Both activities are under the ARMAS goal of providing the "weather" of the radiation environment to improve aircraft crew and passenger safety. Over 5-dozen ARMAS and USEWX flights have successfully demonstrated the operation of a micro dosimeter on commercial aviation altitude aircraft that captures the real-time radiation environment resulting from Galactic Cosmic Rays and Solar Energetic Particles. The real-time radiation exposure is computed as an effective dose rate (body-averaged over the radiative-sensitive organs and tissues in units of microsieverts per hour); total ionizing dose is captured on the aircraft, downlinked in real-time, processed on the ground into effective dose 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 via the web and smart phone apps. Flight altitudes now exceed 60,000 ft. and extend above commercial aviation altitudes into the stratosphere. In this presentation we describe recent ARMAS and USEWX results.

  3. Scanning electron microscopy (Sem) of wings and mouth parts of the Mediterranean Fruit Fly, Ceratitis Capitata (Wield.), as influenced by the sterilizing dose of the gamma radiation

    International Nuclear Information System (INIS)

    El-akhader, E.A.H.

    2005-01-01

    In view of the fact that, any undesirable effects of gamma irradiation with the sterilizing dose (90 Gy) on wings and mouth parts of the Mediterranean fruit fly, Ceratitis Capitata (Wied.), and their associated sensilla will lead indirectly to failure of irradiated males to disperse strongly, to seek out appropriate niches or to behave synchrony with wild males or to success in the courtship with females and/or to mate. Moreover, the fly may fail to suck the plant juice. Using the scanning electron microscopy, this study was investigated. The changes which occurred to the wings and mouth parts of the med fly may be due to the sterilizing dose. One pair of wings was found to have similar typical structures in both sexes differing non-significantly in their measurements. Three different types of located sensilla were observed on each wing namely; trichoid (type sharp and blunt tipped), chaetica (type 1, 2 and 3) and basiconica (type non-socket, socket and papillae). The distribution and measurements of these sensilla were described in the text. The study of the mouth parts of both sexes recorded that there was similar pattern except significant increase between the length of the proboscis of male and female. Four different types of located sensilla were found on the mouth parts of the med fly and their measurements were given in the text. Namely trichoid (type sharp), squameformia (type 1 and socket), chaetica (type 1) and basiconica (type non-socket) were observed. The distal region of the labium was very smooth and did not bear any kind of sensilla. Pupal irradiation with the sterilizing dose resulted in different malformations in both irradiated male and female adult wings and mouth parts and their associated sensilla. Some malformations were observed in the intraveins of the irradiated male wing and in the pseudo tracheae of irradiated female labella

  4. Dose response of alanine and methyl alanine towards gamma and in-situ alpha irradiation

    International Nuclear Information System (INIS)

    Mohapatra, M.; Rajeswari, B.; Bhide, M.K.; Rane, Vinayak; Kadam, R.M.

    2017-01-01

    In situ alpha and external gamma dose response of two ESR (electron spin resonance) dosimetric materials namely alanine and methyl alanine were investigated. It was observed that alanine dosimeter had a better dose response in comparison to methyl alanine for the in-situ alpha irradiation by using 239 Pu powder. On the other hand, in case of gamma radiation, methyl alanine was found to have the sensitivity as twice that of alanine. (author)

  5. Theory of thermoluminescence gamma dose response: The unified interaction model

    International Nuclear Information System (INIS)

    Horowitz, Y.S.

    2001-01-01

    We describe the development of a comprehensive theory of thermoluminescence (TL) dose response, the unified interaction model (UNIM). The UNIM is based on both radiation absorption stage and recombination stage mechanisms and can describe dose response for heavy charged particles (in the framework of the extended track interaction model - ETIM) as well as for isotropically ionising gamma rays and electrons (in the framework of the TC/LC geminate recombination model) in a unified and self-consistent conceptual and mathematical formalism. A theory of optical absorption dose response is also incorporated in the UNIM to describe the radiation absorption stage. The UNIM is applied to the dose response supralinearity characteristics of LiF:Mg,Ti and is especially and uniquely successful in explaining the ionisation density dependence of the supralinearity of composite peak 5 in TLD-100. The UNIM is demonstrated to be capable of explaining either qualitatively or quantitatively all of the major features of TL dose response with many of the variable parameters of the model strongly constrained by ancilliary optical absorption and sensitisation measurements

  6. Scatter Dose in Patients in Radiation Therapy

    International Nuclear Information System (INIS)

    Schmidt, W. F. O.

    2003-01-01

    Patients undergoing radiation therapy are often treated with high energy radiation (bremsstrahlung) which causes scatter doses in the patients from various sources as photon scatter coming from collimator, gantry, patient, patient table or room (walls, floor, air) or particle doses resulting from gamma-particle reactions in the atomic nucleus if the photon energies are above 8 MeV. In the last years new treatment techniques like IMRT (esp the step-and-shoot- or the MIMIC-techniques) have increased interest in these topics again. In the lecture an overview about recent measurements on scatter doses resulting from gantry, table and room shall be given. Scatter doses resulting from the volume treated in the patient to other critical parts of the body like eyes, ovarii etc. have been measured in two diploma works in our institute and are compared with a program (PERIDOSE; van der Giessen, Netherlands) to estimate them. In some cases these scatter doses have led to changes of treatment modalities. Also an overview and estimation of doses resulting from photon-particle interactions is given according to a publication from Gudowska et al.(Gudowska I, Brahme A, Andreo P, Gudowski W, Kierkegaard J. Calculation of absorbed dose and biological effectiveness from photonuclear reactions in a bremsstrahlung beam of end point 50 MeV. Phys Med Biol 1999; 44(9):2099-2125.). Energy dose has been calculated with Monte Carlo-methods and is compared with analytical methods for 50 MV bremsstrahlung. From these data biologically effective doses from particles in different depths of the body can be estimated also for energies used in normal radiotherapy. (author)

  7. Distributions of neutron and gamma doses in phantom under a mixed field

    International Nuclear Information System (INIS)

    Beraud-Sudreau, E.

    1982-06-01

    A calculation program, based on Monte Carlo method, allowed to estimate the absorbed doses relatives to the reactor primary radiation, in a water cubic phantom and in cylindrical phantoms modelized from tissue compositions. This calculation is a theoretical approach of gamma and neutron dose gradient study in an animal phantom. PIN junction dosimetric characteristics have been studied experimentally. Air and water phantom radiation doses measured by PIN junction and lithium 7 fluoride, in reactor field have been compared to doses given by dosimetry classical techniques as tissue equivalent plastic and aluminium ionization chambers. Dosimeter responses have been employed to evaluate neutron and gamma doses in plastinaut (tissue equivalent plastic) and animal (piglet). Dose repartition in the piglet bone medulla has been also determined. This work has been completed by comparisons with Doerschell, Dousset and Brown results and by neutron dose calculations; the dose distribution related to lineic energy transfer in Auxier phantom has been also calculated [fr

  8. Spectral measurements of gamma radiation streaming through ducts

    International Nuclear Information System (INIS)

    Meenakshisundaram, P.K.; Bhatnagar, V.M.; Raghunath, V.M.; Gopinath, D.V.

    1979-01-01

    The paper presents the spectral measurements of gamma radiation streaming through multi-legged rectangular concrete ducts for cesium-137 and cobald-60 sources. Effect of lead lining the inner surface of the duct on the streaming radiation spectrum and optimization of liner thickness for minimum streaming radiation dose have been studied. For three-legged ducts, a comparative analysis of lead lining the entire duct as against lining any one or both the corners of the duct is reported. It is seen that lead lining any one of the corners would reduce the streaming radiation dose by a factor of 5 to 12. Lining both the corners which is nearly as effective as lining the entire duct reduces the dose by a factor of 16 to 60 depending on the soruce energy and duct dimensions. (orig.)

  9. Spatial distribution of gamma radiation levels in surface soils from Jaduguda uranium mineralization zone, Jharkhand, India, using γ-ray spectrometry, and determination of outdoor dose to the population

    Directory of Open Access Journals (Sweden)

    Maharana Mandakini

    2010-01-01

    Full Text Available The concentrations of natural radionuclides in surface soil samples around selected villages of Jaduguda were investigated and compared with the radioactivity level in the region. Concentrations of 238 U, 232 Th, and 40 K were determined by a gamma ray spectrometer using the HPGe detector with 50% relative efficiency, and the radiation dose to the local population was estimated. The average estimated activity concentrations of 238 U, 232 Th, and 40 K in the surface soil were 53.8, 44.2 and 464.2 Bq kg -1 respectively. The average absorbed dose rate in the study area was estimated to be 72.5 nGy h-1, where as the annual effective dose to the population was 0.09 mSv y-1. A correlation analysis was made between measured dose rate and individual radionuclides, in order to delineate the contribution of the respective nuclides towards dose rate. The radio-elemental concentrations of uranium, thorium and potassium estimated for the soils, in the study area, indicated the enrichment of uranium series nuclide. The results of the present study were subsequently compared with international and national recommended values.

  10. Measurement and Calculation of Gamma Radiation from HWZPR Reactor

    International Nuclear Information System (INIS)

    Jalali, Majid

    2006-01-01

    HWZPR is a research reactor with natural uranium fuel, D 2 O moderator and graphite reflector with maximum power of 100 W. It is a suitable means for theoretical research and heavy water reactor experiments. Neutrons from the core participate in different nuclear reactions by interactions with fuel, moderator, graphite and the concrete around the reactor. The results of these interactions are the production of prompt gammas in the environment. Useful information is gained by the reactor gamma spectrum measurement from point of view of relative quantity and energy distribution of direct and scattered radiations. Reactor gamma ray spectrum has been gathered in different places around the reactor by HPGe detector. In analysis of these spectra, 1 H(n,γ) 2 H, 16 O(n,n'γ) 16 O, 2 H(n,γ) 3 H and 238 U(n,γ) 239 U reactions occurring in reactor moderator and fuel, are important. The measured spectrum has been primarily estimated by the MCNP code. There is agreement between the code and the experiments in some points. The scattered gamma rays from 27 Al (n,γ) 28 Al reaction in the reactor tank, are the most among the gammas scattered in the reactor environment. Also the dose calculations by MCNP code show that 72% of gamma dose belongs to the energy range 3-11 MeV from reactor gamma spectrum and the danger of exposure from the reactor high-energy photons is serious. (author)

  11. Evaluation of optical fibres as gamma radiation dosimeter

    International Nuclear Information System (INIS)

    Bohra, Dinesh; Chaudhary, H.S.; Panwar, Lalit; Vaijapurkar, S.G.; Bhatnagar, P.K.; Dasgupta, K.

    2005-01-01

    Semiconductor base gamma and neutron sensors are the fastest and popular dosimeters and are in competition with Thermoluminescence (TL) and Radio photoluminescence (RPL) dosimeters. All over the world armed forces require a dosimeter which records cumulative doses of ionizing radiations from mcGy to 10 Gy and is readable repeatedly without loss of dose information. TL dosimeters do not meet the criteria and RPL dosimeter meet the expectations and are in use by armed forces. Technologists have used laser as an excitation source to stimulate the glass and have achieved success in recording gamma doses of occupational/accidental span (mcGy to 10 Gy). However synthesizing RPL glass batches with exactly same characteristics predoses is a difficult task. Silicon base phosphorous doped step index multimode optical fibre can be made in a significant quantity and large number of dosimeters from it can be achieved with uniform predose. The radiation induced transmission loss gives a measure of gamma dose which is cumulative, readable repeatedly without loss of information. Assorted composition, core dia optical fibres have been synthesized and evaluated for dose linearity, dose rate independence, fading, length optimization. Here in is described some results of recent experiments and sensitivities achieved. (author)

  12. Sterilization plants equipped with the isotopic gamma radiation sources

    International Nuclear Information System (INIS)

    Mehta, K.; Chmielewski, A.G.

    2007-01-01

    Presentation describes different isotopic gamma radiation sources applicable for sterilization of food and medical materials. Certain gamma pallet irradiators, mini gamma irradiators and different scale gamma tote irradiators are presented. It is concluded, that about two hundreds plants with gamma radiation sources operates in different countries. However, industrially developed countries must construct much more plants than operates now

  13. Luminescent polymethyl methacrylate modified by gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Morais, Guilherme F. [Faculdade de Tecnologia de Sao Paulo (FATEC-ZL), Sao Paulo, SP (Brazil); Forster, Pedro L.; Marchini, Leonardo G.; Lugao, Ademar B.; Parra, Duclerc F., E-mail: dfparra@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Thin films of PMMA (polymethyl methacrylate) doped with luminescent complexes have been studied and developed for applications in advanced technologies. The problem of stability of these films is focused in this study. Films stabilization by reaction with fluorinated monomers is a recent study that aims to increase its luminescence properties for long time. The films were prepared by dilution of PMMA in chloroform with addition of europium complex, at proportion of 5% by weight of polymer. The luminescent polymer films were obtained by casting. Thin layer slides of the film were separated in three parts. One was reacted with fluorinated monomers (C{sub 2}F{sub 4}) in closed reactor for 48 hours. A second part was reacted with C{sub 2}F{sub 4} after irradiation in gamma source at 5 kGy in simultaneous process. The last part was used as obtained. The luminescent polymer matrices were characterized using the techniques of infrared (FTIR) and thermogravimetry (TGA/DTG). Samples of the films were, in presence of fluorine monomers, exposed to ionizing radiation in dose of 5 kGy, for react with monomers in the doped polymer surface. In this case the effects of radiation were evaluated on the luminescent films. (author)

  14. Luminescent polymethyl methacrylate modified by gamma radiation

    International Nuclear Information System (INIS)

    Morais, Guilherme F.; Forster, Pedro L.; Marchini, Leonardo G.; Lugao, Ademar B.; Parra, Duclerc F.

    2011-01-01

    Thin films of PMMA (polymethyl methacrylate) doped with luminescent complexes have been studied and developed for applications in advanced technologies. The problem of stability of these films is focused in this study. Films stabilization by reaction with fluorinated monomers is a recent study that aims to increase its luminescence properties for long time. The films were prepared by dilution of PMMA in chloroform with addition of europium complex, at proportion of 5% by weight of polymer. The luminescent polymer films were obtained by casting. Thin layer slides of the film were separated in three parts. One was reacted with fluorinated monomers (C 2 F 4 ) in closed reactor for 48 hours. A second part was reacted with C 2 F 4 after irradiation in gamma source at 5 kGy in simultaneous process. The last part was used as obtained. The luminescent polymer matrices were characterized using the techniques of infrared (FTIR) and thermogravimetry (TGA/DTG). Samples of the films were, in presence of fluorine monomers, exposed to ionizing radiation in dose of 5 kGy, for react with monomers in the doped polymer surface. In this case the effects of radiation were evaluated on the luminescent films. (author)

  15. On the honeybee resistance to gamma radiation; Sur la resistance au rayonnement gamma de l'abeille ouvriere

    Energy Technology Data Exchange (ETDEWEB)

    Courtois, G.; Lecomte, J. [Commissariat a l' energie atomique et aux energies alternatives - CEA, Section des Applications des Radioelements, Centre d' Etudes Nucleaires, Saclay, Station de Recherches Apicoles, Bures-sur-Yvette (France)

    1960-07-01

    The honeybee, when irradiated by gamma radiations from a cobalt-60 source can stand a 18000 r dose without any apparent harm. Noticeable harm is observed for 90000 r. while immediate death of 100% of the individuals is obtained with a 200000 r dose. The physiological condition of the honeybee plays an important role in its resistance to gamma radiation. Reprint of a paper published in Annales de l'abeille, IV, 1959, p. 285-290 [French] L'Abeille butineuse irradiee par le rayonnement gamma issu d'une source de Cobalt 60 supporte sans dommages apparents une dose de 18000 r. Des dommages tres appreciables sont observes pour 90000 r. Une dose de 200000 r entraine la mort immediate de 100% des individus. L'etat physiologique de l'Abeille joue un role important dans la resistance au rayonnement gamma. Reproduction d'un article publie dans Annales de l'abeille, IV, 1959, p. 285-290.

  16. Effect of single lithium doses on haemopoiesis regeneration after radiation exposure in mice

    International Nuclear Information System (INIS)

    Krajewski, K.

    1988-01-01

    The reported experiment failed to demonstrate any effect of single doses of lithium carbonate on haemopoiesis regeneration in experimental haematological syndrome of acute radiation sickness. The effects of gamma radiation on blood formation are shown. 3 figs., 6 refs. (author)

  17. Determination of gamma radiation dose for destruction of Salmonella spp. in chicken flesh.; Determinacao da dose de radiacao gama para a destruicao de Salmonella spp. em carne de frango

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Andreia Ferreira dos

    1997-07-01

    The aim of this study was to determinate: 1) the radio sensibility of Salmonella typhimurium ATCC 14028 in soy trypticase broth; 2) the radio sensibility of Salmonella typhimurium ATCC 14028 in chicken thigh and; 3) to recommend a radiation dose which can be non hazardous for human consumption

  18. A simulation study on the dose distribution for a single beam of the gamma knife

    International Nuclear Information System (INIS)

    Chen, Chin-cheng; Jiang, Shiang-Huei; Lee, Chung-chi; Shiau, Cheng-Ying

    2000-01-01

    The purpose of this study is to evaluate the impact of the tissue heterogeneity on the dose distribution for a single beam of the gamma knife. The EGS4 Monte Carlo code was used to simulate both depth and radial profiles of the radiation dose in homogeneous and heterogeneous phantoms, respectively. The results are compared with the dose distribution calculated using the mathematical model of Gamma Plan, the treatment planning system of the gamma knife. The skull and sinus heterogeneity were simulated by a Teflon shell and an air shell, respectively. It was found that the tissue heterogeneity caused significant perturbation on the absolute depth dose at the focus as well as on the depth-dose distribution near the phantom surface and/or at the interface but little effect on the radial dose distribution. The effect of the beam aperture on the depth-dose distribution was also investigated in this study. (author)

  19. Comparison of gamma radiation - induced effects in two human prostate cancer cells

    International Nuclear Information System (INIS)

    Vucic, V.; Adzic, M.; Ruzdijic, S.; Radojcic, M.B. . E-mail address of corresponding author: vesnav@vin.bg.ac.yu; Vucic, V.)

    2005-01-01

    In this study, the effects of gamma radiation on two hormone refractory human prostate cancer cell lines, DU 145 and PC-3, were followed. It was shown that gamma radiation induced significant inhibition of cell proliferation and viability in dose dependent manner. Antiproliferative effects of radiation were similar in both cell lines, and more pronounced than cytotoxic effects. In addition to that, PC-3 cell line was more resistant to radiation -induced cytotoxicity. (author)

  20. Prenatal radiation exposure. Dose calculation

    International Nuclear Information System (INIS)

    Scharwaechter, C.; Schwartz, C.A.; Haage, P.; Roeser, A.

    2015-01-01

    The unborn child requires special protection. In this context, the indication for an X-ray examination is to be checked critically. If thereupon radiation of the lower abdomen including the uterus cannot be avoided, the examination should be postponed until the end of pregnancy or alternative examination techniques should be considered. Under certain circumstances, either accidental or in unavoidable cases after a thorough risk assessment, radiation exposure of the unborn may take place. In some of these cases an expert radiation hygiene consultation may be required. This consultation should comprise the expected risks for the unborn while not perturbing the mother or the involved medical staff. For the risk assessment in case of an in-utero X-ray exposition deterministic damages with a defined threshold dose are distinguished from stochastic damages without a definable threshold dose. The occurrence of deterministic damages depends on the dose and the developmental stage of the unborn at the time of radiation. To calculate the risks of an in-utero radiation exposure a three-stage concept is commonly applied. Depending on the amount of radiation, the radiation dose is either estimated, roughly calculated using standard tables or, in critical cases, accurately calculated based on the individual event. The complexity of the calculation thereby increases from stage to stage. An estimation based on stage one is easily feasible whereas calculations based on stages two and especially three are more complex and often necessitate execution by specialists. This article demonstrates in detail the risks for the unborn child pertaining to its developmental phase and explains the three-stage concept as an evaluation scheme. It should be noted, that all risk estimations are subject to considerable uncertainties.

  1. Radioactivity Risk Assessment of Radon and Gamma Dose at One Uranium Tailings Pond in China

    Science.gov (United States)

    Lou, Yalong; Liu, Yong; Peng, Guowen; Zhao, Guodong; Zhang, Yan; Yang, Zhu

    2018-01-01

    A year-long monitoring of gamma radiation effective dose rate and radon concentration had been done in the reservoir area of one uranium tailings pond in Hunan province (The monitoring area included indoor and outdoor area of residential buildings and workshops, tailings dam slope). Afterwards, the annual effective radiation dose of the people in that radiation environment had been calculated based on the results of monitoring, as well as a radiation risk assessment. According to the assessment, gamma radiation effective dose rate and radon concentration in the monitoring area were low, and the annual effective radiation dose was far below the international standard (30mSv), which showed that the radiation would not put the people’s health at risk. However, the annual effective radiation dose of gamma was far above that of radon in the area of uranium tailings pond; therefore, it’s advisable to take quarantine measures in in the area of uranium tailings pond to keep the surrounding residents away from unnecessary ionizing radiation.

  2. Radiation dose monitoring in the clinical routine

    Energy Technology Data Exchange (ETDEWEB)

    Guberina, Nika [UK Essen (Germany). Radiology

    2017-04-15

    Here we describe the first clinical experiences regarding the use of an automated radiation dose management software to monitor the radiation dose of patients during routine examinations. Many software solutions for monitoring radiation dose have emerged in the last decade. The continuous progress in radiological techniques, new scan features, scanner generations and protocols are the primary challenge for radiation dose monitoring software systems. To simulate valid dose calculations, radiation dose monitoring systems have to follow current trends and stay constantly up-to-date. The dose management software is connected to all devices at our institute and conducts automatic data acquisition and radiation dose calculation. The system incorporates 18 virtual phantoms based on the Cristy phantom family, estimating doses in newborns to adults. Dose calculation relies on a Monte Carlo simulation engine. Our first practical experiences demonstrate that the software is capable of dose estimation in the clinical routine. Its implementation and use have some limitations that can be overcome. The software is promising and allows assessment of radiation doses, like organ and effective doses according to ICRP 60 and ICRP 103, patient radiation dose history and cumulative radiation doses. Furthermore, we are able to determine local diagnostic reference doses. The radiation dose monitoring software systems can facilitate networking between hospitals and radiological departments, thus refining radiation doses and implementing reference doses at substantially lower levels.

  3. Degradation of electrical insulation of polyethylene under thermal and radiation environment, (4). [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Shuhei; Murabayashi, Fumio; Sawa, Goro [Mie Univ., Tsu (Japan); Yamaguchi, Shinji; Ieda, Masayuki

    1982-12-01

    Although the quality assurance guideline for the cables used for the safety and protection systems of nuclear power plants is given by IEEE Standards 323 and 383-1974, in addition, it is important to clarify the aging process under the complex environment of heat and radiation and the equivalence of the accelerated aging test of insulating materials. The authors performed the sequential (H.T-..gamma.. or ..gamma..-HT) and simultaneous (..gamma.., HT) application of respective aging factors of heat and radiation to non-additive low density polyethylene films by changing dose rate as the first stage, to clarify the dose rate dependence of the aging. They mainly investigated the dielectric properties, and forwarded investigation based on the change of carbonyl group by infrared spectrometry and residual free radicals by ESR analysis. In the samples irradiated with ..gamma..-ray only and those irradiated with ..gamma..-ray after thermal treatment for 7 hours at 90 deg C, the absorption coefficient ..cap alpha.. of carbonyl group increased with dose in the range from 3 Mrad to 60 Mrad, and both samples showed approximately the same ..cap alpha.. value. The ..cap alpha.. value of the samples thermally treated after irradiation was larger than that of the samples treated in the reverse order, and the difference between them increased with the increase of dose. The values of dielectric tangent delta at room temperature and 1 kHz for the samples (..gamma..) and (HT-..gamma..) increased with dose, and were almost the same, but those for the samples (..gamma..-HT) and (..gamma.., HT) were larger than the former two.

  4. Beta and gamma dose calculations for PWR and BWR containments

    International Nuclear Information System (INIS)

    King, D.B.

    1989-07-01

    Analyses of gamma and beta dose in selected regions in PWR and BWR containment buildings have been performed for a range of fission product releases from selected severe accidents. The objective of this study was to determine the radiation dose that safety-related equipment could experience during the selected severe accident sequences. The resulting dose calculations demonstrate the extent to which design basis accident qualified equipment could also be qualified for the severe accident environments. Surry was chosen as the representative PWR plant while Peach Bottom was selected to represent BWRs. Battelle Columbus Laboratory performed the source term release analyses. The AB epsilon scenario (an intermediate to large LOCA with failure to recover onsite or offsite electrical power) was selected as the base case Surry accident, and the AE scenario (a large break LOCA with one initiating event and a combination of failures in two emergency cooling systems) was selected as the base case Peach Bottom accident. Radionuclide release was bounded for both scenarios by including spray operation and arrested sequences as variations of the base scenarios. Sandia National Laboratories used the source terms to calculate dose to selected containment regions. Scenarios with sprays operational resulted in a total dose comparable to that (2.20 x 10 8 rads) used in current equipment qualification testing. The base case scenarios resulted in some calculated doses roughly an order of magnitude above the current 2.20 x 10 8 rad equipment qualification test region. 8 refs., 23 figs., 12 tabs

  5. Dose limits for ionising radiation

    International Nuclear Information System (INIS)

    Gifford, D.

    1989-01-01