WorldWideScience

Sample records for radioactivity artificially induced

  1. Artificial radioactivity in Carlingford Lough

    The principal objective of this study was to assess whether radioactivity concentrations in a wide range of environmental materials from the Lough were enhanced above general levels found elsewhere along the east and north-east coasts of Ireland. Other objectives included an examination of gamma dose rates in air over inter-tidal sediments throughout the Lough and an examination of coastal soils to determine the extent of sea-to-land transfer of plutonium and , by inference, americium

  2. Induced radioactivity at CERN

    1970-01-01

    A description of some of the problems and some of the advantages associated with the phenomenon of induced radioactivity at accelerator centres such as CERN. The author has worked in this field for several years and has recently written a book 'Induced Radioactivity' published by North-Holland.

  3. Artificial radioactivity in the North Sea

    The question of radioactive contamination of the environment is a problem of world-wide importance. The North Sea is an important example of a sea region heavily used by man and therefore polluted by different contaminants including radionuclides. A review of the present knowledge of the radiological situation of the North Sea and adjacent sea regions is given. The sources of artificial radionuclides and their distribution, behaviour and fate in this shallow sea area are discussed. (author)

  4. Principle of natural and artificial radioactive series equivalency

    In the present paper one approach used under development of radioactive waste management conception is under consideration. This approach is based on the principle of natural and artificial radioactive series radiotoxic equivalency. The radioactivity of natural and artificial radioactive series has been calculated for 109 - years period. The toxicity evaluation for natural and artificial series has also been made. The correlation between natural radioactive series and their predecessors - actinides produced in thermal and fast reactors - has been considered. It has been shown that systematized reactor series data had great scientific significance and the principle of differential calculation of radiotoxicity was necessary to realize long-lived radioactive waste and uranium and thorium ore radiotoxicity equivalency conception. The calculations show that the execution of equivalency principle is possible for uranium series (4n+2, 4n+1). It is a problem for thorium. series. This principle is impracticable for neptunium series. (author)

  5. Influence of natural radioactive aerosols on artificial radioactivity detection in the Spanish surveillance networks

    The device used for continuous measurements of artificial α and β activity in Spanish radiological surveillance networks is the LB BAI 9850 monitor from the Berthold Company. The temporal variation of radon decay product equilibrium introduces a varying background signal in the artificial radioactivity in these monitors. This unwanted background signal can be significantly reduced by analyzing natural radioactive aerosols and their influence on the monitor

  6. Natural and Artificial Radioactivity in Drinkingwater in Malaga, Spain

    The measurement of radioactivity in drinking water permits us to determine the exposure of the population to radiation from the habitual consumption of water. An intensive study of the water supply in the city of Malaga during 2002-2010 has been carried out in order to determine the gross alpha and gross beta activities and natural and artificial radionuclides present in drinking water. A database on natural and artificial radioactivity in water was created. The results indicated that a high percentage of the water sample contains a total gross alpha and beta concentration of less than 0.10 Bq/L and 1 Bq/L, respectively. The main objectives were: (1) to analyse gross alpha and gross beta activities and to know the statistical distributions; (2) to study the levels of natural and artificial radionuclides; (3) to determine a possible mathematical correlation between the radionuclides and several factors. (author)

  7. Induced radioactivity in LDEF components

    Harmon, B. A.; Fishman, G. J.; Parnell, T. A.; Laird, C. E.

    1992-01-01

    A systematic study of the induced radioactivity of the Long Duration Exposure Facility (LDEF) is being carried out in order to gather information about the low earth orbit radiation environment and its effects on materials. The large mass of the LDEF spacecraft, its stabilized configuration, and long mission duration have presented an opportunity to determine space radiation-induced radioactivities with a precision not possible before. Data presented include preliminary activities for steel and aluminum structural samples, and activation subexperiment foils. Effects seen in the data show a clear indication of the trapped proton anisotropy in the South Atlantic Anomaly and suggest contributions from different sources of external radiation fluxes.

  8. Modelling of artificial radioactivity migration in environment: a survey

    The aim of this report is to present a compilation and description of models to assess the environmental behaviour and effects of accidental and routine releases of artificial radioactivity from nuclear power facilities. About 60 models are described and a card is given for each one, to indicate in summarized form its features and data content. This collection is intended to help in developing specific personal models by assembling different parts chosen among the most suitable ones of different models of various degrees of sophistication

  9. Medical imaging was boosted by the discovery of artificial radioactivity

    This article draws the history of medical imaging since the discovery of artificial radioactivity in 1934. The author reviews the PET (positron emission tomography) and MRI (magnetic resonance imaging) technologies and presents the recent progress in neuro-sciences that have been made possible by using these 2 technologies. Brain imaging has allowed to show: - the impact of emotions on logical mental processes and on mental performances, - the management of memory in the brain of talented quick reckoners, - the degeneration of neurons, and - the link between autism and the presence of structural and functional anomalies in the brain. (A.C.)

  10. Radioactivity of natural and artificial building materials - a comparative study.

    Szabó, Zs; Völgyesi, P; Nagy, H É; Szabó, Cs; Kis, Z; Csorba, O

    2013-04-01

    Building materials and their additives contain radioactive isotopes, which can increase both external and internal radioactive exposures of humans. In this study Hungarian natural (adobe) and artificial (brick, concrete, coal slag, coal slag concrete and gas silicate) building materials were examined. We qualified 40 samples based on their radium equivalent, activity concentration, external hazard and internal hazard indices and the determined threshold values of these parameters. Absorbed dose rate and annual effective dose for inhabitants living in buildings made of these building materials were also evaluated. The calculations are based on (226)Ra, (232)Th and (40)K activity concentrations determined by gamma-ray spectrometry. Measured radionuclide concentrations and hence, calculated indices and doses of artificial building materials show a rather disparate distribution compared to adobes. The studied coal slag samples among the artificial building materials have elevated (226)Ra content. Natural, i.e. adobe and also brick samples contain higher amount of (40)K compared to other artificial building materials. Correlation coefficients among radionuclide concentrations are consistent with the values in the literature and connected to the natural geochemical behavior of U, Th and K elements. Seven samples (coal slag and coal slag concrete) exceed any of the threshold values of the calculated hazard indices, however only three of them are considered to be risky to use according to the fact that the building material was used in bulk amount or in restricted usage. It is shown, that using different indices can lead to different conclusions; hence we recommend considering more of the indices at the same time when building materials are studied. Additionally, adding two times their statistical uncertainties to their values before comparing to thresholds should be considered for providing a more conservative qualification. We have defined radon hazard portion to point

  11. Natural and artificial radioactivity determination of some medicinal plants

    Several medicinal plants used in Italy were analysed to determine natural and artificial radioactivity in those parts (leaves, fruits, seeds, roots, peduncles, flowers, barks, berries, thallus) used generally as remedies. The radionuclides were determined by alpha (238U, 210Po) and gamma (214Pb-Bi, 210Pb, 40K and 137Cs) spectrometry. 238U ranged between dry-1; 210Po between dry-1; 214Pb-214Bi between dry-1; 210Pb between dry-1; 40K between 66.2 and 3582.0 Bq kgdry-1; 137Cs between dry-1. The percentage of 210Po extraction in infusion and decoction was also determined; the arithmetical mean value of percentage of 210Po extraction resulted 20.7 ± 7.5.

  12. Artificial radioactivity on the coasts of Northern Ireland

    In Northern Ireland, measurements of artificial radioactivity have been made in inshore seawater, beach sand and mud, sea spray, the air and material deposited from the air, and in coastal soil. The objective was to determine the levels in the coastal environment and also to assess the magnitude of transport of radioactivity from sea to land in sea spray. The results would provide a basis for the development of a model describing sea to land transfer, and allowing the resulting population exposure to be assessed. The results showed the presence of plutonium isotopes, 241Am and 137Cs in some samples of each of the media measured, but concentrations were low in all cases. Large variation in the concentrations in seawater and beach sediment were attributed to variations in dispersion and in the characteristics of the sediment. Sea to land transfer of actinides was detected in samples of sea spray and in air and deposition measurements. Only at some sites on the east coast could the resulting accumulation in soil close to the beach be distinguished from fallout. Following May 1986 137Cs from Chernobyl could be detected in air and in atmospheric deposition. A preliminary assessment of the exposure of the population to the actinides and 137Cs in all the media showed that the resulting dose is a small fraction of the recognised limit. (author)

  13. Nuclear chemistry fifty years after the discovery of artificial radioactivity

    In January 1934, the observation and the chemical identification of radiophosphorus as a reaction product in the bombardment of Aluminium by alpha particles have been the first step of a new scientific branch: Nuclear Chemistry. We describe here how this discovery in itself contains the frame of all the development which has followed. It consisted in four stages, each of them being a crucial starting point. The first one is the possibility for a total balance of the nuclear reaction in the exit channels, so that reaction mechanisms can be studied. The second, the most important perhaps, is the opening of nuclear synthesis. Nuclear chemists can now interfere into nuclear matter and instead of staying as observers of the radioactive decays of natural isotopes, they were able to build up a numerous chart of various nuclear species, going step by step further and further away from the nuclear stability conditions. The third aspect of the discovery was the appearance of a new mode of radioactive decay with the production of the first particle an antimater. 50 years later, the instability due to a much larger excess of protons is known to induce the proton emission radioactivity for new species like 109I or 115Cs, in the vicinity of proton unstability. Finally, the last point, so fertile for the future, was the observation of a neutron in the exit channel, so that neutron fluxes could result from alpha induced nuclear reactions and became such a strong tool for the production of transuranium elements and for nuclear fission. In the present survey, the wide interest of the second point, i.e. the nuclear synthesis, is emphasized, as well as the huge change in the technical methods

  14. Artificial radioactivity in tide washed pastures in south west Scotland

    A study has been carried out to determine the impact of Sellafield discharges on the levels of radioactivity in tide washed pastures in south west Scotland. The likely areas of tidal inundations along the Nith, Urr, Dee, Fleet and Cree (including nearby Bladnoch) rivers were assessed using maps and aerials photographs. These were then visited and gamma radiation measurements taken at regular intervals to enable the external dose from anthropogenic nuclides to be estimated. A further survey followed where soil cores were taken from the areas on each river where the external dose appeared highest and analysed for a range of artificial radionuclides. The levels of 137Cs, 134Cs, 238Pu, 239+240Pu and 241Am found, although small, were clearly in excess of the background from other sources. A habit survey was carried out to provide site specific information of tide washed pasture usage, which, with the spatial radionuclide data was used to estimate doses to appropriate critical groups. The maximum annual dose calculated to arise was 60 μSv which is less than 6% of the ICRP principal dose limit of 1 mSv. (author)

  15. Natural and induced radioactivity in food

    One of the first questions often asked about irradiated food is whether it is radioactive. Not many people understand that food and any natural substance contains natural radioactivity which can be measurable. It is therefore important to put the issue on natural radioactivity and possible induced radioactivity in food in perspective. While there is a clear consensus among the scientific community that no radioactivity is induced when food is irradiated by gamma rays from cobalt-60 or cesium-137, electron generated by a machine with energy less than 10 million electron volt (MeV) or X rays produced generated by a machine with energy less than 5 MeV. However, data to this effect were published many years ago and are not easy to find. As food irradiation is gaining wide acceptance in many countries, it was considered timely to compile data on natural and induced radioactivity in food into one document. We are grateful to A. Brynjolfsson, one of the few experts who have the knowledge on this subject as well as wide experience on food irradiation, who collected, compiled and evaluated all data on this subject into one report. This publication provides clear explanations not only why radioactivity cannot be induced in food irradiated by radiation sources mentioned above but to what extent the increase in dose or energy level of radiation sources would induce significantly radioactivity in food. The compilation of such data was prompted by a desire to increase the energy limit and the absorbed dose based on the need to irradiate thicker samples of food and to use sterilizing dose up to 60 kGy. This publication concluded that the increase in radiation background dose from consumption of food irradiated to an average dose up to 60 kGy with gamma rays from cobalt- 60 or cesium-137, with 10 MeV electrons or with 5 MeV X rays is insignificant. In addition, food irradiated with X ray with energy up to 7.5 MeV to a dose of 30 kGy has radioactivity well below natural

  16. INFLUENCE OF ELECTROACUPUNCTURE ON ARTIFICIAL ABORTION-INDUCED SIDE EFFECTS

    田丽颖

    2001-01-01

    In the present study, the effect of electroecupuncture (EA) of acupoints of Ren, Spleen and Stomach Meridians on artificial abortion-induced side effects was observed in 100 artificial abortion women. In comparison with 45 artificial abortion women in the control group (who had not accepted EA treatment), EA possessed significant effects in relieving abdominal pain, reducing vaginal bleeding duration, lowering infection rate and infertility rate after artificial abortion operation.

  17. Induced radioactivity due to high energy radiation

    In high energy radiation facilities, the reaction called ''Spallation'' (nuclear spallation) becomes to contribute greatly to the production of induced radioactivity in the facility structures, water and air, besides thermal neutron capture reaction and the reaction accompanied by nucleon release due to fast neutrons. Spallation products have three features. The first is the abundance of the kinds of nuclides produced, the second is that the major part of the products are positron emitters, and the third is that the most products have short life. If the estimation of the radioactivity intensity and amount of spallation products is intended from the viewpoint of radiation protection, experimental values or the semi-empirical equation determined on the basis of experimental values should be used. Rudstam formula is well-known as such a semi-empirical equation. Though it is important for health physics to estimate the induced activity production due to high energy radiation quantitatively and as accurately as possible, the quantitative estimation is practically quite difficult. The problems in radiation control caused by induced activity include the spatial dose rate in operation and during shut down, the radioactive contamination of workers and the treatment and disposal of activated water and air. It is necessary in the actual radiation control duties to develop the monitoring techniques or radioactivity concentration, because the routine monitoring techniques seem to have not yet been established, and the calibration and assessment procedures seem to leave room for the improvement. (Wakatsuki, Y.)

  18. NATURAL AND ARTIFICIAL RADIOACTIVITY IN IMPORTED FISHERY PRODUCTS

    R. Cavallina

    2013-02-01

    Full Text Available Considering the growing public concern over marine environmental quality, a program of monitoring radionuclids in imported fishery products has been established. The analyses have been performed by gamma spectrometry allowing the rapid detection of many artificial radionuclides such as 137Cs, 134Cs and 40K. The data obtained show Cs radionuclides levels within expected limits. The detection of natural radionuclide K showed different levels in the same fishery product as they came from different sea areas.

  19. NATURAL AND ARTIFICIAL RADIOACTIVITY IN IMPORTED FISHERY PRODUCTS

    M.C. Campagna; A. Nardoni; R. Cavallina

    2010-01-01

    Considering the growing public concern over marine environmental quality, a program of monitoring radionuclids in imported fishery products has been established. The analyses have been performed by gamma spectrometry allowing the rapid detection of many artificial radionuclides such as 137Cs, 134Cs and 40K. The data obtained show Cs radionuclides levels within expected limits. The detection of natural radionuclide K showed different levels in the same fishery product as they came from differe...

  20. Daily measurements of natural and artificial radioactivity in 1962

    Daily numerical results of measures concerning β activity of the air, either from natural, owing to thoron, of from artificial, owing to active aerosols origin, will be found in this statement. The all results are expressed in μμcurie/m3 of air. Proceedings of measure and technic of standardization, which were the matter of anterior papers, have not been discussed once more here. (author)

  1. Evaluation of induced radioactivity in 10 MeV-Electron irradiated spices, (2)

    In order to check radioactivity of beta-emmitters produced by (γ, n) reactions which could occur at energies up to 10 MeV, black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy. Beta-rays were counted using a 2π gas flow counter and a liquid scintillation counter. Any induced radioactivity could not be detected in irradiated samples. When inorganic compounds containing the nuclides in the list were artificially added in the samples and were irradiated, the β-activities were detected. From the amount of observed radioactivities of β-emmitters produced in the compounds as photonuclear products, it is concluded that the induced radioactivity in natural samples by 10 MeV-electron irradiation were far smaller than natural radioactivity from 40K contained in the samples and, hence, its biological effects should be negligible. (author)

  2. Detection of pulmonary aspiration by radioactive measurements of bronchial material in artificially ventilated infants

    Detection of pulmonary aspiration of gastric contents by radioactive measurements of bronchial material was performed in 13 artificially ventilated infants (14 studies) after ingestion of 99m-technetium sulfure colloide. 10/13 had strong clinical suspicion of recurrent pulmonary aspiration. 10 out of 14 examinations were positive (71%). This technique is more sensitive than scintigraphic methods described in literature and particularly adapted to these patients

  3. Artificial intelligence methods applied for quantitative analysis of natural radioactive sources

    Highlights: ► Basic description of artificial neural networks. ► Natural gamma ray sources and problem of detections. ► Application of neural network for peak detection and activity determination. - Abstract: Artificial neural network (ANN) represents one of artificial intelligence methods in the field of modeling and uncertainty in different applications. The objective of the proposed work was focused to apply ANN to identify isotopes and to predict uncertainties of their activities of some natural radioactive sources. The method was tested for analyzing gamma-ray spectra emitted from natural radionuclides in soil samples detected by a high-resolution gamma-ray spectrometry based on HPGe (high purity germanium). The principle of the suggested method is described, including, relevant input parameters definition, input data scaling and networks training. It is clear that there is satisfactory agreement between obtained and predicted results using neural network.

  4. Application of two-barrier model of radioactive agent transport in sea water for analyzing artificial radionuclide release from containers with radioactive waste dumped in Kara Sea

    Modeling of artificial radionuclide transport in sea water is crucial for prognosis of radioecological situation in regions where dumping of radioactive waste had been made and/or accidents with nuclear submarines had taken place. Distribution of artificial radionuclides in bottom sediments can be a detector of radionuclide release from dumped or sunk objects to marine environment. Proper model can determine the dependence between radionuclide distribution in sediments and radionuclide release. Following report describes two-barrier model of radioactive agent transport in sea water. It was tested on data from 1994 - 2013 expeditions to Novaya Zemlya bays, where regular dumping of solid radioactive waste was practiced by the former USSR from the early 1960's until 1990. Two-barrier model agrees with experimental data and allows more accurate determination of time and intensity of artificial radionuclide release from dumped containers. (authors)

  5. Application of two-barrier model of radioactive agent transport in sea water for analyzing artificial radionuclide release from containers with radioactive waste dumped in Kara Sea

    Grishin, Denis S.; Laykin, Andrey I.; Kuchin, Nickolay L.; Platovskikh, Yuri A. [Krylov State Research Center, Saint Petersburg, 44 Moskovskoe shosse, 196158 (Russian Federation)

    2014-07-01

    Modeling of artificial radionuclide transport in sea water is crucial for prognosis of radioecological situation in regions where dumping of radioactive waste had been made and/or accidents with nuclear submarines had taken place. Distribution of artificial radionuclides in bottom sediments can be a detector of radionuclide release from dumped or sunk objects to marine environment. Proper model can determine the dependence between radionuclide distribution in sediments and radionuclide release. Following report describes two-barrier model of radioactive agent transport in sea water. It was tested on data from 1994 - 2013 expeditions to Novaya Zemlya bays, where regular dumping of solid radioactive waste was practiced by the former USSR from the early 1960's until 1990. Two-barrier model agrees with experimental data and allows more accurate determination of time and intensity of artificial radionuclide release from dumped containers. (authors)

  6. Robust Type-specific Hemisynapses Induced by Artificial Dendrites

    Kim, Eun Joong; Jeon, Chang Su; Lee, Soo Youn; Hwang, Inseong; Chung, Taek Dong

    2016-04-01

    Type-specificity of synapses, excitatory and inhibitory, regulates information process in neural networks via chemical neurotransmitters. To lay a foundation of synapse-based neural interfaces, artificial dendrites are generated by covering abiotic substrata with ectodomains of type-specific synaptogenic proteins that are C-terminally tagged with biotinylated fluorescent proteins. The excitatory artificial synapses displaying engineered ectodomains of postsynaptic neuroligin-1 (NL1) induce the formation of excitatory presynapses with mixed culture of neurons in various developmental stages, while the inhibitory artificial dendrites displaying engineered NL2 and Slitrk3 induce inhibitory presynapses only with mature neurons. By contrast, if the artificial dendrites are applied to the axonal components of micropatterned neurons, correctly-matched synaptic specificity emerges regardless of the neuronal developmental stages. The hemisynapses retain their initially established type-specificity during neuronal development and maintain their synaptic strength provided live neurons, implying the possibility of durable synapse-based biointerfaces.

  7. Solutes problems and main results in the area of natural and artificial radioactivity

    The list of research problems and main results in natural and artificial radioactivity monitoring in the Slovak Republic is presented.The mean values of 78 000 measurements of natural radioactivity are: potassium 1.6 %, uranium 3.3 ppm, thorium 9.4 ppm, relation of Th/U 2.8, Th/K 5.8, and U/K 2.1. Mean dose rate for Slovakia is 63.3 nGy/h.The mean activity of cesium-137, measured on 5500 points, is 2200 Bq/m2 that is mean dose rate 3.5 nGy/h. The arithmetic mean of concentration of uranium in underground waters of Slovakia is .0034 mg/dm3, mean volume activity of radium 222 is 0.048 Bq/dm3 and of radon-222 is 15.51 Bq/dm3

  8. Artificial neural network application in isotopic characterization of radioactive waste drums

    One of the most important aspects to the development of the nuclear technology is the safe management of the radioactive waste arising from several stages of the nuclear fuel cycles, as well as from production and use of radioisotope in the medicine, industry and research centers. The accurate characterization of this waste is not a simple task, given to its diversity in isotopic composition and non homogeneity in the space distribution and mass density. In this work it was developed a methodology for quantification and localization of radionuclides not non homogeneously distributed in a 200 liters drum based in the Monte Carlo Method and Artificial Neural Network (RNA), for application in the isotopic characterization of the stored radioactive waste at IPEN. Theoretical arrangements had been constructed involving the division of the radioactive waste drum in some units or cells and some possible configurations of source intensities. Beyond the determination of the detection positions, the respective detection efficiencies for each position in function of each cell of the drum had been obtained. After the construction and the training of the RNA's for each developed theoretical arrangement, the validation of the method were carried out for the two arrangements that had presented the best performance. The results obtained show that the methodology developed in this study could be an effective tool for isotopic characterization of radioactive wastes contained in many kind of packages. (author)

  9. Radioactivity of natural and artificial building materials – a comparative study

    Building materials and their additives contain radioactive isotopes, which can increase both external and internal radioactive exposures of humans. In this study Hungarian natural (adobe) and artificial (brick, concrete, coal slag, coal slag concrete and gas silicate) building materials were examined. We qualified 40 samples based on their radium equivalent, activity concentration, external hazard and internal hazard indices and the determined threshold values of these parameters. Absorbed dose rate and annual effective dose for inhabitants living in buildings made of these building materials were also evaluated. The calculations are based on 226Ra, 232Th and 40K activity concentrations determined by gamma-ray spectrometry. Measured radionuclide concentrations and hence, calculated indices and doses of artificial building materials show a rather disparate distribution compared to adobes. The studied coal slag samples among the artificial building materials have elevated 226Ra content. Natural, i.e. adobe and also brick samples contain higher amount of 40K compared to other artificial building materials. Correlation coefficients among radionuclide concentrations are consistent with the values in the literature and connected to the natural geochemical behavior of U, Th and K elements. Seven samples (coal slag and coal slag concrete) exceed any of the threshold values of the calculated hazard indices, however only three of them are considered to be risky to use according to the fact that the building material was used in bulk amount or in restricted usage. It is shown, that using different indices can lead to different conclusions; hence we recommend considering more of the indices at the same time when building materials are studied. Additionally, adding two times their statistical uncertainties to their values before comparing to thresholds should be considered for providing a more conservative qualification. We have defined radon hazard portion to point to the

  10. Evaluation of induced radioactivity in 10 MeV-Electron irradiated spices, (2); [beta]-ray counting

    Katayama, Tadashi; Furuta, Masakazu; Shibata, Setsuko; Matsunami, Tadao; Ito, Norio; Mizohata, Akira; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1994-02-01

    In order to check radioactivity of beta-emmitters produced by ([gamma], n) reactions which could occur at energies up to 10 MeV, black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy. Beta-rays were counted using a 2[pi] gas flow counter and a liquid scintillation counter. Any induced radioactivity could not be detected in irradiated samples. When inorganic compounds containing the nuclides in the list were artificially added in the samples and were irradiated, the [beta]-activities were detected. From the amount of observed radioactivities of [beta]-emmitters produced in the compounds as photonuclear products, it is concluded that the induced radioactivity in natural samples by 10 MeV-electron irradiation were far smaller than natural radioactivity from [sup 40]K contained in the samples and, hence, its biological effects should be negligible. (author).

  11. Determination of the natural and artificial radioactivity of a selection of traditional Mexican medicinal herbs by gamma spectrometry

    This work presents the results of a gamma spectrometry analysis of 30 traditional Mexican medicinal herbs. The analysis was carried out using low level background shielding, a hyper-pure germanium detector, and a multichannel analyzer system. Natural and artificial radioactivity concentration from 226Ra (through 214Pb and 214Bi), 228Th (through 208Tl), 228Ra (through 228Ac), 40K, and 137Cs were determined in this analysis. The results show low concentration levels of natural radioactivity and no artificial radionuclides, and different contents of natural 40K, in the studied medicinal herbs. These low concentration levels of natural radionuclides, cannot be consider a health risk for common consumers. (author)

  12. Human Health Impact of Natural and Artificial Radioactivity Levels in the Sediments and Fish of Bonny Estuary, Niger Delta, Nigeria

    Bolaji B. Babatunde; Francis D. Sikoki; Ibitoruh Hart

    2015-01-01

    There is widespread contamination of the environment of the Niger Delta, which may include enhanced background levels of naturally occurring radioactive materials (NORM) due to oil production and rapid urbanization activities. Sediments and seafood from the Bonny estuary, Niger Delta, were collected for the purpose of determining baseline data on artificial and natural radioactivity and estimation of effective doses for the public due to ingestion of seafood from the study area. The highest a...

  13. Radioactively induced noise in gas-sampling uranium calorimeters

    The signal induced by radioactivity of a U238 absorber in a cell of a gas-sampling uranium calorimeter was studied. By means of Campbell's theorem, the levels of the radioactively induced noise in uranium gas-sampling calorimeters was calculated. It was shown that in order to obtain similar radioactive noise performance as U-liquid argon or U-scintillator combinations, the α-particles from the uranium must be stopped before entering the sensing volume of gas-uranium calorimeters

  14. Metal Complexes Containing Natural and and Artificial Radioactive Elements and Their Applications

    Oxana V. Kharissova

    2014-07-01

    Full Text Available Recent advances (during the 2007–2014 period in the coordination and organometallic chemistry of compounds containing natural and artificially prepared radionuclides (actinides and technetium, are reviewed. Radioactive isotopes of naturally stable elements are not included for discussion in this work. Actinide and technetium complexes with O-, N-, N,O, N,S-, P-containing ligands, as well π-organometallics are discussed from the view point of their synthesis, properties, and main applications. On the basis of their properties, several mono-, bi-, tri-, tetra- or polydentate ligands have been designed for specific recognition of some particular radionuclides, and can be used in the processes of nuclear waste remediation, i.e., recycling of nuclear fuel and the separation of actinides and fission products from waste solutions or for analytical determination of actinides in solutions; actinide metal complexes are also usefulas catalysts forcoupling gaseous carbon monoxide,as well as antimicrobial and anti-fungi agents due to their biological activity. Radioactive labeling based on the short-lived metastable nuclide technetium-99m (99mTc for biomedical use as heart, lung, kidney, bone, brain, liver or cancer imaging agents is also discussed. Finally, the promising applications of technetium labeling of nanomaterials, with potential applications as drug transport and delivery vehicles, radiotherapeutic agents or radiotracers for monitoring metabolic pathways, are also described.

  15. Metal complexes containing natural and and artificial radioactive elements and their applications.

    Kharissova, Oxana V; Méndez-Rojas, Miguel A; Kharisov, Boris I; Méndez, Ubaldo Ortiz; Martínez, Perla Elizondo

    2014-01-01

    Recent advances (during the 2007-2014 period) in the coordination and organometallic chemistry of compounds containing natural and artificially prepared radionuclides (actinides and technetium), are reviewed. Radioactive isotopes of naturally stable elements are not included for discussion in this work. Actinide and technetium complexes with O-, N-, N,O, N,S-, P-containing ligands, as well π-organometallics are discussed from the view point of their synthesis, properties, and main applications. On the basis of their properties, several mono-, bi-, tri-, tetra- or polydentate ligands have been designed for specific recognition of some particular radionuclides, and can be used in the processes of nuclear waste remediation, i.e., recycling of nuclear fuel and the separation of actinides and fission products from waste solutions or for analytical determination of actinides in solutions; actinide metal complexes are also usefulas catalysts forcoupling gaseous carbon monoxide,as well as antimicrobial and anti-fungi agents due to their biological activity. Radioactive labeling based on the short-lived metastable nuclide technetium-99m ((99m)Tc) for biomedical use as heart, lung, kidney, bone, brain, liver or cancer imaging agents is also discussed. Finally, the promising applications of technetium labeling of nanomaterials, with potential applications as drug transport and delivery vehicles, radiotherapeutic agents or radiotracers for monitoring metabolic pathways, are also described. PMID:25061724

  16. Radioactivity

    This educative booklet give a general overview of radioactivity: history, structure of matter, radiations, radioactivity law, origin of radioactivity, radioactivity uses, radioprotection and measurement units. (J.S.)

  17. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966)

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author)

  18. Artificial neural networks in the evaluation of the radioactive waste drums activity

    The mathematical techniques are becoming more important to solve geometry and standard identification problems. The gamma spectrometry of radioactive waste drums would be a complex solution problem. The main difficulty is the detectors calibration for this geometry; the waste is not homogeneously distributed inside the drums, therefore there are many possible combinations between the activity and the position of these radionuclides inside the drums, making the preparation of calibration standards impracticable. This work describes the development of a methodology to estimate the activity of a 200 L radioactive waste drum, as well as a mapping of the waste distribution, using Artificial Neural Network. The neural network data set entry obtaining was based on the possible detection efficiency combination with 10 sources activities varying from 0 to 74 x 103 Bq. The set up consists of a 200 L drum divided in 5 layers. Ten detectors were positioned all the way through a parallel line to the drum axis, from 15 cm of its surface. The Cesium -137 radionuclide source was used. The 50 efficiency obtained values (10 detectors and 5 layers), combined with the 10 source intensities resulted in a 100,000 lines for 15 columns matrix, with all the possible combinations of source intensity and the Cs-137 position in the 5 layers of the drum. This archive was divided in 2 parts to compose the set of training: input and target files. The MatLab 7.0 module of neural networks was used for training. The net architecture has 10 neurons in the input layer, 18 in the hidden layer and 5 in the output layer. The training algorithm was the 'traincgb' and after 300 'epoch s' the medium square error was 0.00108172. This methodology allows knowing the detection positions answers in a heterogeneous distribution of radionuclides inside a 200 L waste drum; in consequence it is possible to estimate the total activity of the drum in the training neural network limits. The results accuracy depends on

  19. Radioactivity: A Natural Phenomenon.

    Ronneau, C.

    1990-01-01

    Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

  20. Avalanches and disorder-induced criticality in artificial spin ices

    We show that both square and kagome artificial spin ice systems exhibit disorder-induced nonequilibrium phase transitions, with power law avalanche distributions at the critical disorder level. The different nature of geometrical frustration in the two lattices produces distinct types of critical avalanche behavior. For the square ice, the avalanches involve the propagation of locally stable domain walls separating the two polarized ground states, and the scaling collapse agrees with an interface depinning mechanism. In contrast, avalanches in the fully frustrated kagome ice exhibit pronounced branching behaviors that resemble those found in directed percolation. The kagome ice also shows an interesting crossover in the power-law scaling of the avalanches at low disorder. Our results show that artificial spin ices are ideal systems in which to study nonequilibrium critical point phenomena. (paper)

  1. Monitoring induced denitrification in an artificial aquifer recharge system.

    Grau-Martinez, Alba; Torrentó, Clara; Folch, Albert; Domènech, Cristina; Otero, Neus; Soler, Albert

    2014-05-01

    As demands on groundwater increase, artificial recharge is becoming a common method for enhancing groundwater supply. The Llobregat River is a strategic water supply resource to the Barcelona metropolitan area (Catalonia, NE Spain). Aquifer overexploitation has leaded to both a decrease of groundwater level and seawater intrusion, with the consequent deterioration of water quality. In the middle section of the aquifer, in Sant Vicenç del Horts, decantation and infiltration ponds recharged by water from the Llobregat River (highly affected from wastewater treatment plant effluents), were installed in 2007, in the framework of the ENSAT Life+ project. At the bottom of the infiltration pond, a vegetal compost layer was installed to promote the growth of bacteria, to induce denitrification and to create favourable conditions for contaminant biodegradation. This layer consists on a mixture of compost, aquifer material, clay and iron oxide. Understanding the fate of contaminants, such as nitrate, during artificial aquifer recharge is required to evaluate the impact of artificial recharge in groundwater quality. In order to distinguish the source of nitrate and to evaluate the capability of the organic reactive layer to induce denitrification, a multi-isotopic approach coupled with hydrogeochemical data was performed. Groundwater samples, as well as river samples, were sampled during artificial and natural recharge periods. The isotopic analysis included: δ15N and δ18O of dissolved nitrate, δ34S and δ18O of dissolved sulphate, δ13C of dissolved inorganic carbon, and δ2H and δ18O of water. Dissolved nitrate isotopic composition (δ15NNO3 from +9 to +21 o and δ18ONO3 from +3 to +16 ) demonstrated that heterotrophic denitrification induced by the reactive layer was taking place during the artificial recharge periods. An approximation to the extent of nitrate attenuation was calculated, showing a range between 95 and 99% or between 35 and 45%, by using the extreme

  2. Artificial radionuclides in the ecosystems of the gulfs in the Kola peninsula and in the areas of radioactive wastes keeping

    The results of radioactive contamination investigations carried out in the Kola Peninsula gulf's ecosystems in the vicinity of the places of radioactive wastes keeping are presented. These investigations were conducted during 1994-2004 by specialists of the Murmansk Marine Biological Institute KSC RAS. The data on the artificial radionuclides contents in bottom sediments, water and hydrobiontes of the Kola, the Motovsky Bays and gulfs of the Barents Sea are presented. Coefficients values of caesium radionuclides distribution between water and bottom sediments of the Kola Bay obtained experimentally and developed on the basis of the data on the composition and amount of artificial radionuclides in bottom sediments classification of bays and gulfs are also given. (author)

  3. Ultracold Fermions in a Cavity-Induced Artificial Magnetic Field

    Kollath, Corinna; Sheikhan, Ameneh; Wolff, Stefan; Brennecke, Ferdinand

    2016-02-01

    We propose how a fermionic quantum gas confined to an optical lattice and coupled to an optical cavity can self-organize into a state where the spontaneously emerging cavity field amplitude induces an artificial magnetic field. The fermions form either a chiral insulator or a chiral liquid carrying chiral currents. The feedback mechanism via the dynamical cavity field enables robust and fast switching in time of the chiral phases, and the cavity output can be employed for a direct nondestructive measurement of the chiral current.

  4. Induced Radioactivity in Recovered Skylab Materials. [gamma ray spectra

    Fishman, G. J.; Meegan, C. A.

    1980-01-01

    Four radioactive isotopes found in aluminum and stainless steel samples from Skylab debris were recovered in Australia. The low-level activity was induced by high-energy protons and neutrons in the space environment. Measurements of the specific activities are given.

  5. Preliminary results on artificial radioactivity and elemental content of samples from Black Sea

    During the international expedition of the research vessel Prof. Vodyanitskiy on the Black Sea, in December 1999, samples of sea water and sediment were collected and analyzed for elemental content and radioactivity. The cruise covered the mouths of the Dniester and Danube River, the Crimean coastal waters and the offshore area. The sediment, collected by an EPA Box corer was separated in layers. Sediment samples were analyzed by gamma spectroscopy for the artificial occurring radionuclide Cs-137. The concentration of some major, minor and trace elements was determined by X-ray fluorescence (XRF) technique. For the water samples, Cs-137 concentration varied between (26.3 ± 3.4) mBq/l and (41.2 ± 5.6) mBq/l for the surface water; a value of (9.9 ± 1.8) mBq/l was found for a deep water sample collected far offshore. The concentration of Sr-90 did not vary significantly from a station to another and was around 11 mBq/l. The concentration of tritium was low (between 24 and 7 T.U.), in the range reported in the recent literature. For all the sampling locations the maximum of the 137 Cs specific activity in sediment samples was found in the surface layer. In the samples collected from the stations 3 and 4, close to the mouths of Danube and Dniester Rivers, higher values up to (128 ± 6) Bq/kg were found. A similar elemental composition of sediment samples in the locations mentioned above was found. Cr and Ni were detected only in the sediment sample collected near the Crimean shore, and are probably correlated to the industrial discharges. (authors)

  6. Calculations and observations of induced radioactivity in spaceborne materials

    All material in space becomes radioactive due to nuclear interactions with cosmic rays, radiation belt protons and solar flare particles. This poses a particular problem for gamma-ray detectors as the energy depositions fall in the precise window of interest. On the positive side, samples returned to earth can be monitored to provide information on the primary and secondary radiations experienced. Here, radiation transport calculations are compared with observations of induced radioactivity obtained from the OSSE experiment on the Compton Observatory and the CREAM experiment on Space Shuttle. These results illustrate the importance of secondary particles

  7. Emanations and 'induced' radioactivity: from mystery to (mis)use

    The natural Rn isotopes were discovered within the period 1899-1902 and at that time referred to as emanations because they came out (emanated) of sources/materials containing actinium, thorium and radium, respectively. The (somewhat mysterious) emanations appeared to disintegrate into radioactive decay products which by depositing at solid surfaces gave rise to 'induced' radioactivity i.e. radioactive substances with various half-lives. Following the discovery of the emanations the volume of the research involving them and their disintegration products grew steeply. The identity of a number of these radioactive products was soon established. Radium emanation was soon used as a source of RaD (210Pb) to be applied as an 'indicator' (radiotracer) for lead in a study on the solubility of lead sulphide and lead chromate. Moreover, radium and its emanation were introduced into the medical practice. Inhaling radon and drinking radon-containing water became an accepted medicinal use (or misuse?) of that gas. Shortly after the turn of the century, the healing (?) action of natural springs (spas) was attributed to their radium emanation, i.e. radon. Bathing in radioactive spring water and drinking it became very popular. Even today, bathing in radon-containing water is still a common medical treatment in Jachymov, Czech Republic. (author)

  8. In Silico Evolved lac Operons Exhibit Bistability for Artificial Inducers, but Not for Lactose

    van Hoek, M. J. A.; Hogeweg, P.

    2006-01-01

    Bistability in the lac operon of Escherichia coli has been widely studied, both experimentally and theoretically. Experimentally, bistability has been observed when E. coli is induced by an artificial, nonmetabolizable, inducer. However, if the lac operon is induced with lactose, the natural inducer, bistability has not been demonstrated. We derive an analytical expression that can predict the occurrence of bistability both for artificial inducers and lactose. We find very different condition...

  9. Radioactivity Induced by Neutrons: a Thermodynamic Approach to Radiative Capture

    De Gregorio, Alberto

    2005-01-01

    When Enrico Fermi discovered slow neutrons, he accounted for their great efficiency in inducing radioactivity by merely mentioning the well-known scattering cross-section between neutrons and protons. He did not refer to capture cross-section, at that early stage. It is put forward that a thermodynamic approach to neutron-proton radiative capture then widely debated might underlie his early accounts. Fermi had already met with a similar approach, and repeatedly used it.

  10. Medical imaging was boosted by the discovery of artificial radioactivity; L'imagerie medicale revelee par la radioactivite

    Demarthon, F.; Dupuy-Maury, F.; Donnars, O

    2002-08-01

    This article draws the history of medical imaging since the discovery of artificial radioactivity in 1934. The author reviews the PET (positron emission tomography) and MRI (magnetic resonance imaging) technologies and presents the recent progress in neuro-sciences that have been made possible by using these 2 technologies. Brain imaging has allowed to show: - the impact of emotions on logical mental processes and on mental performances, - the management of memory in the brain of talented quick reckoners, - the degeneration of neurons, and - the link between autism and the presence of structural and functional anomalies in the brain. (A.C.)

  11. Prediction of radiation induced liver disease using artificial neural networks

    The objective of this study was to evaluate the efficiency of predicting radiation induced liver disease (RILD) with an artificial neural network (ANN) model. From August 2000 to November 2004, a total of 93 primary liver carcinoma (PLC) patients with single lesion and associated with hepatic cirrhosis of Child-Pugh grade A, were treated with hypofractionated three-dimensional conformal radiotherapy (3DCRT). Eight out of 93 patients were diagnosed RILD. Ninety-three patients were randomly divided into two subsets (training set and verification set). In model A, the ratio of patient numbers was 1:1 for training and verification set, and in model B, the ratio was 2:1. The areas under receiver-operating characteristic (ROC) curves were 0.8897 and 0.8831 for model A and B, respectively. Sensitivity, specificity, accuracy, positive prediction value (PPV) and negative prediction value (NPV) were 0.875 (7/8), 0.882 (75/85), 0.882 (82/93), 0.412 (7/17) and 0.987 (75/76) for model A, and 0.750 (6/8), 0.800 (68/85), 0.796 (74/93), 0.261 (6/23) and 0.971 (68/70) for model B. ANN was proved high accuracy for prediction of RILD. It could be used together with other models and dosimetric parameters to evaluate hepatic irradiation plans. (author)

  12. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963)

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author)

  13. State of radionuclides in seawater. Comparison of natural stable and artificial radioactive isotope s of mercury and zinc in natural waters of the arid zone of the USSR

    This paper studies the state of stable and artificial radioactive isotopes of merury and zinc in natural waters of the arid zone of the USSR by radioactivity and radiochemical methods. Convergent results have been obtained for the dissolved forms of mercury and zinc in natural waters of the arid zone in a comparison of the results of radioactivation analysis and laboratory simulation using the radionuclides mercury-203 and zinc-65

  14. Induced radioactivity of the IHEP proton synchrotron beam extraction equipment

    The measurement results of induced radioactivity of the beam extraction equipment during 1972-1978 are presented. All the values are given to the moment of the accelerator stop. The experimental data permits to predict further possible variations of the induced radioactivity levels of the equipment. Given are the measures required for reduction of the accelerator equipment irradiation, which are the following: 1) compensation of residual distortion of a closed beam orbit in the course of the induction system operation; 2) limitation of the intensity of drop on the internal targets up to the 11 protons per target level over a cycle; 3) putting into operation the program control system for the duration of a current pulse of a linear accelerator to minimize the beam residues at the 70 GeV energy during physical experiments; 4) construction of the system of beam interception and cutting-off to ensure effective energy suppression of uncontrolled beam residues and localization of their radiation effect; 5) extraction of a high-energy beam out of the accelerator during the experiments (e.g., into the neutrino channel for apparatus adjusting) instead of its dropping on the interceptor-target; 6) beam orbit controlling in the case of multiturn injection into the accelerator

  15. Artificial radioactivity in the vicinity of St. Marianna University School of Medicine after the Chernobyl reactor accident

    Following the Chernobyl reactor accident on April 26, 1986, rain water and atomospheric dust were monitored for their possible contamination by artificial radionuclides on the roof of the building of our medical school from April 30 through June 8, 1986. Radiological monitoring was also performed on cabbages obtained from a nearby field, city water, cow's milk produced in Kanagawa Prefecture and human milk obtained from a volunteer living in Kawasaki. Our campus and the nearby area were exposed to 131I from May 2 through 22 by rainfall and from May 1 through 15 by atomospheric dust. In particular, rain water on May 4 and May 5 contained 7600 pCi (282 Bq)/l and 6000 pCi (222 Bq)/l, respectively. The cabbage specimen obtained on May 7 was contaminated by 131I with 808 pCi/kg wet weight, but another specimen obtained on June 6 was not contaminated by any detectable amounts of 131I. No radioactivity was detected in city water during the period monitored. Cow's milk and human milk contained, as a total of β-radioactivity, 1412 pCi (52 Bq)/l and 915 pCi (34 Bq)/l, respectively. However, parallel determinations on their potassium concentrations revealed that these radioactivities were due entirely to natural 40K. The degree of radiological contamination in and around our campus following the Chernobyl accident was mostly below the action levels above which the governments of several countries involving Japan would take preventive measures against possible radiation damages. Although 131I radioactivities contained in the rain water of the first week of May, 1986 significantly exceeded the action level for this radionuclide, their effects on human health were considered negligible and undetectable in the vicinity of our school. (author)

  16. The electrical charging of inactive aerosols in high ionised atmosphere, the electrical charging of artificial beta radioactive aerosols

    The electrical properties of aerosols greatly influence their transport and deposition in a containment. In a bipolar ionic atmosphere, a neutral electric charge on aerosols is commonly assumed. However, many studies report a different charge distribution in some situations, like highly ionised atmosphere or in the case of radioactive aerosols. Such situations could arise from a hypothetical accident in a nuclear power plant. Within the framework of safety studies which are carried out at IPSN, our aims were the study of electrical properties of aerosols in highly ionised atmosphere, and the study of artificial radioactive aerosols, in order to suggest experimental validation of available theories. For this purpose, we designed an experimental device that allows us to measure non-radioactive aerosol charge distribution under high gamma irradiation, up to 104 Gy/h. With our experimental device we also studied the properties of small ions in the medium. Our results show a variation of the charge distribution in highly ionised atmosphere. The charge increases with the dose of gamma ray. We have related this variation with the one of the small ions in the gases, according to theoretical prediction. However, the model overestimates slightly our experimental results. In the case of the radioactive aerosols, we have designed an original experimental device, which allows us to study the charge distribution of a 137Cs aerosol. Our results show that the electric charging of such aerosols is strongly dependent on evolution parameters in a containment. So, our results underline a great enhancement of self-charging of particles which are sampled in a confined medium. Our results are qualitatively in agreement with the theoretical model; nevertheless the latter underestimates appreciably the self-charging, owing to the fact that wall effects are not taken into account. (author)

  17. Artificial Intelligence based Solver for Governing Model of Radioactivity Cooling, Self-gravitating Clouds and Clusters of Galaxies

    Junaid Ali Khan

    2013-06-01

    Full Text Available In this study, a reliable alternate platform is developed based on artificial neural network optimized with soft computing technique for a non-linear singular system that can model complex physical phenomenas of the nature like radioactivity cooling, self-gravitating clouds and clusters of galaxies. The trial solution is mathematically represented by feed-forward neural network. A cost function is defined in an unsupervised manner that is optimized by a probabilistic meta-heuristic global search technique based on annealing in metallurgy. The results of the designed scheme are evaluated by comparing with the desired response of the system. The applicability, stability and reliability of the proposed method is validated by Monte Carlo simulations.

  18. Using radioactivity

    The leaflet discusses the following: radioactivity; radioisotopes; uses of ionising radiations; radioactivity from (a) naturally occurring radioactive elements, and (b) artificially produced radioisotopes; uses of radioactivity in medicine, (a) clinical diagnostic, (b) therapeutic (c) sterilization of medical equipment and materials; environmental uses as tracers; industrial applications, e.g. tracers and radiography; ensuring safety. (U.K.)

  19. Evaluation of induced radioactivity in 10 MeV-electron irradiated spices, (1)

    Black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electrons from a linear accelerator to a dose of 100 kGy and radioactivity was measured in order to estimate induced radioactivity in the irradiated foods. Induced radioactivity could not be detected significantly by γ-ray spectrometry in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list of photonuclear reactions which could produce radioactivity below 10 MeV. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H50 according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from 40K contained in the samples. (author)

  20. NATURAL AND ARTIFICIAL RADIOACTIVITY IN BULGARIAN SOILS ALONG THE DANUBE RIVER

    I YORDANOVA

    2005-07-01

    Full Text Available Data from gamma-spectrometry analyses of soils and sediments samples taken along the Danube river is presented in the paper. Results about the content of natural and artifi cial radionuclides like Sr-90 and Cs-137 are discussed. The region around the Kozloduj NPP including its exclusion zone is investigated in more details. Data from the last years is compared with such from former investigations of similar samples from the region. The soil is a natural depot and initial reservoir for spreading of all man-made radionuclides and natural radioactivity. The man-made isotopes with the longest half-life time, like Sr-90 and Cs-137 are mainly investigated. Because of their feature to be bioelements, that is to include themselves in human’s metabolism, they are especially dangerous when their concentrations in the nutritious chain increase. That is why the investigation of these nuclides together with the natural once like uranium, thorium and radium started in 1978 with annual determination of their concentrations in soils collected from the region of “Kozloduj” NPP and some places along the Danube river potentially exposed to radioactive contamination. The aim was to make a picture of the radioecological status of the soils along the Danube river. The period after 1986 is concerned as the accident in Chernobyl’s NPP changed basically the radioactive situation in the country.

  1. Radiation Sialadenitis Induced by High-dose Radioactive Iodine Therapy

    Jeong, Shin Young; Lee, Jaetae [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2010-06-15

    Radioactive iodine ({sup 131}I) is accumulated in the thyroid tissue and plays an important role in the treatment of differentiated papillary and follicular cancers after thyroidectomy. Simultaneously, {sup 131}I is concentrated in the salivary glands and secreted into the saliva. Dose-related damage to the salivary parenchyma results from the {sup 131}I irradiation. Salivary gland swelling and pain, usually involving the parotid, can be seen. The symptoms may develop immediately after a therapeutic dose of {sup 131}I and/or months later and progress in intensity with time. In conjunction with the radiation sialadenitis, secondary complications reported include xerostomia, taste alterations, infection, increases in caries, facial nerve involvement, candidiasis, and neoplasia. Prevention of {sup 131}I sialadenitis may involve the use of sialogogic agents to hasten the transit time of the radioactive iodine through the salivary glands. However, studies are not available to delineate the efficacy of this approach. Treatment of the varied complications that may develop encompass numerous approaches and include gland massage, sialogogic agents, duct probing, antibiotics, mouthwashes, good oral hygiene, and adequate hydration. Recently interventional sialoendoscopy has been introduced an effective tool for the management of patients with {sup 131}I-induced sialadenitis that is unresponsive to medical treatment.

  2. Radiation Sialadenitis Induced by High-dose Radioactive Iodine Therapy

    Radioactive iodine (131I) is accumulated in the thyroid tissue and plays an important role in the treatment of differentiated papillary and follicular cancers after thyroidectomy. Simultaneously, 131I is concentrated in the salivary glands and secreted into the saliva. Dose-related damage to the salivary parenchyma results from the 131I irradiation. Salivary gland swelling and pain, usually involving the parotid, can be seen. The symptoms may develop immediately after a therapeutic dose of 131I and/or months later and progress in intensity with time. In conjunction with the radiation sialadenitis, secondary complications reported include xerostomia, taste alterations, infection, increases in caries, facial nerve involvement, candidiasis, and neoplasia. Prevention of 131I sialadenitis may involve the use of sialogogic agents to hasten the transit time of the radioactive iodine through the salivary glands. However, studies are not available to delineate the efficacy of this approach. Treatment of the varied complications that may develop encompass numerous approaches and include gland massage, sialogogic agents, duct probing, antibiotics, mouthwashes, good oral hygiene, and adequate hydration. Recently interventional sialoendoscopy has been introduced an effective tool for the management of patients with 131I-induced sialadenitis that is unresponsive to medical treatment.

  3. Human Health Impact of Natural and Artificial Radioactivity Levels in the Sediments and Fish of Bonny Estuary, Niger Delta, Nigeria

    Bolaji B. Babatunde

    2015-11-01

    Full Text Available There is widespread contamination of the environment of the Niger Delta, which may include enhanced background levels of naturally occurring radioactive materials (NORM due to oil production and rapid urbanization activities. Sediments and seafood from the Bonny estuary, Niger Delta, were collected for the purpose of determining baseline data on artificial and natural radioactivity and estimation of effective doses for the public due to ingestion of seafood from the study area. The highest and lowest activity concentrations were reported for 40K and 137Cs in both sediments and fish samples of the Bonny estuary. There was some evidence of spatial variability in the 40K and 137Cs data, with the latter being the likely result of dredging. Other radionuclides were not significantly different between sites impacted by industrial activities or not. Activity of radionuclides measured in the sediments of the study area were higher than reported elsewhere in the Niger Delta and Nigeria and higher than reported global averages by UNSCEAR. The total highest activity concentration in all fish species of gamma emitting radionuclides was observed for 40K, followed by 238U, 232Th and 226Ra, respectively, while 137Cs had the lowest activity concentration. However, 210Po activities were the most important in terms of dose contribution. Consumption of molluscs at typical rates could result in doses exceeding 1 mSv·y−1. Although this baseline data may not be conclusive on prevailing trends in radioactivity in the study area, higher consumption rates of the species studied may have public health consequences due to effects of low dose ionising radiation.

  4. Computational Catalysis Using the Artificial Force Induced Reaction Method.

    Sameera, W M C; Maeda, Satoshi; Morokuma, Keiji

    2016-04-19

    The artificial force induced reaction (AFIR) method in the global reaction route mapping (GRRM) strategy is an automatic approach to explore all important reaction paths of complex reactions. Most traditional methods in computational catalysis require guess reaction paths. On the other hand, the AFIR approach locates local minima (LMs) and transition states (TSs) of reaction paths without a guess, and therefore finds unanticipated as well as anticipated reaction paths. The AFIR method has been applied for multicomponent organic reactions, such as the aldol reaction, Passerini reaction, Biginelli reaction, and phase-transfer catalysis. In the presence of several reactants, many equilibrium structures are possible, leading to a number of reaction pathways. The AFIR method in the GRRM strategy determines all of the important equilibrium structures and subsequent reaction paths systematically. As the AFIR search is fully automatic, exhaustive trial-and-error and guess-and-check processes by the user can be eliminated. At the same time, the AFIR search is systematic, and therefore a more accurate and comprehensive description of the reaction mechanism can be determined. The AFIR method has been used for the study of full catalytic cycles and reaction steps in transition metal catalysis, such as cobalt-catalyzed hydroformylation and iron-catalyzed carbon-carbon bond formation reactions in aqueous media. Some AFIR applications have targeted the selectivity-determining step of transition-metal-catalyzed asymmetric reactions, including stereoselective water-tolerant lanthanide Lewis acid-catalyzed Mukaiyama aldol reactions. In terms of establishing the selectivity of a reaction, systematic sampling of the transition states is critical. In this direction, AFIR is very useful for performing a systematic and automatic determination of TSs. In the presence of a comprehensive description of the transition states, the selectivity of the reaction can be calculated more accurately

  5. Radioactivity

    This pedagogical document presents the origin, effects and uses of radioactivity: where does radioactivity comes from, effects on the body, measurement, protection against radiations, uses in the medical field, in the electric power industry, in the food (ionization, radio-mutagenesis, irradiations) and other industries (radiography, gauges, detectors, irradiations, tracers), and in research activities (dating, preservation of cultural objects). The document ends with some examples of irradiation levels (examples of natural radioactivity, distribution of the various sources of exposure in France). (J.S.)

  6. Transport and dispersion of artificial radioactivity in the Arctic Ocean - Model studies and observations -

    The Arctic Ocean and the adjacent shelf regions are subject to growing concern because of increasing environmental problems. The most crucial problem arises probably from the dumping of nuclear waste in the Barents and the Kara Sea. But also the great Siberian rivers Ob and Yenisei which drain huge land areas and industrial zones may contribute to the input of pollutants into the Arctic environment. First results of a joint project are described which combines numerical model studies and experimental field work in order to investigate the potential pathways and dispersion of radioactive contaminants in the Arctic Ocean. (author)

  7. Radioactivity

    Tables are presented of trends in annual emissions of radioactive gaseous effluents at sites of civil establishments in the U.K. Trends in the discharge to surface and coastal water sites in the U.K. and trends in the radioactivity of solid wastes dumped in the N.E. Atlantic and in the volume and activity level of wastes disposed at sites in the U.K. are presented. Tables of radioactivity in samples of fish and shellfish at selected sites are presented. Radioactivity from global fallout and the annual mean ratio of 90Sr to calcium, and concentrations of 137Cs in milk are given. Trends in estimated collective doses from the consumption of fish and shellfish in the U.K. and Europe are presented. (U.K.)

  8. Evaluation of artificial radioactivity of the north Western mediterranean sea and evaluation of the sanitary consequences

    The results of radiological measurements of the north west mediterranean observation network outline the level of artificial radionuclides coming from industrial seewages, 106Ru and from atmospheric fall out, 137Cs and sup(239+240)Pu measured on 3 differents types of bioindicators: Mytilus sp., Posidonia oceanica (L.) Del. and demersal fishes as Solea sp., Anguilla anguilla L., Conger conger L. Mytilus sp. is quite a perfect bioindicator of radionuclides contamination but must be linked with fishes sampling which muscles concentrate Cesium at higher level. The sanitary consequences for the waterside population involved by molluscs and fishes ingestion contamined by these 3 radionuclides lead to a fraction (10-5) of the annual dose limit recommanded by the ICRP 26

  9. Studies of artificial radioactivity in the coastal environment of northern Scotland: a review

    This review brings measurements that have been made over the last 10-15 years of the concentrations of a number of artificial radionuclides in various media in the northern-Scottish coastal environment. The radionuclides include 60Co, 90Sr, 136Cs, 137Cs, 238Pu, 239,240Pu, and 241Am. The media include nearshore and offshore seawater, beach sand and sediments, seaweeds, winkles, spume, deposits on rocks and soils, sheep faeces, and atmospheric deposition. The various radionuclide sources that contribute to the study area are described. Some transfer mechanisms that operate between different media for different radionuclides are discussed, and the radiological significance of the observed radionuclide concentrations is briefly described. (Author)

  10. Natural and artificial radioactivity in milk and dairy products for human consumption (1971-2003)

    Between 1971 and 2003, radioactivity analyses were performed in several dairy products (fresh milk, milk in powder, evaporated milk and in mixed-cereal flours) as part of the program of national environmental radiological surveillance developed by the Department of Environment Control of the Peruvian Nuclear Energy Institute. Analytical assays were performed to evaluate Cs-137, Cs-134, I-131, K-40, Sr-90 (by gamma spectroscopy) and gross beta activity (by beta counting). The obtained values do not represent radiosanitary risk for the population and confirm the presence of K-40 as the main radionuclide in this type of samples. The application of IAEA dosimetric factors allowed calculating intake doses from dairy products in a much lower level than the limits established by international regulation bodies. (author)

  11. Artificial and natural radioactivity measurements in the vicinity of Ghana nuclear research reactor (GHARR-1)

    Radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs in soil and water samples around the Ghana Research Reactor-1 (GHARR-1) and the immediate surroundings have been investigated using gamma spectrometry. The primary aim of this study was to establish baseline radioactivity levels in the environs of GHARR-1. The average activity concentration in soil for 226Ra, 232Th, 40K and 137Cs were 19.8 Bqkg-1, 40.4 Bqkg-1, 95.3 Bqkg-1 and 1.5 Bqkg-1 respectively. For the water samples the average activity concentration of 226Ra was 2.15 Bql-1, 232Th was 0.61 Bql-1, 40K was 10.75Bql-1 and 137Cs was 0.47 Bql-1. The 226Ra and 232Th concentrations compare quite well with world averages, whilst the 40K concentration was lower than the world average. The activity concentrations of 137Cs observed in the samples are within the range of background. concentrations. The estimated average annual effective dose from external exposure to soil and ingestion of water samples was calculated to be 0.64 mSv. The estimated outdoor external gamma dose rate measured in air ranged from 10-430 nGyh-1 with an average value of 41 nGyh-1 which is lower than the worldwide average value of 60 nGyh-1. In the case of the water samples, the average annual effective value was higher than the WHO guideline value of 0.1 mSvy-1 (author)

  12. Application of naturally occurring isotopes and artificial radioactive tracer for monitoring water flooding in oil field

    Water flooding is an important operation to enhance oil recovery. Water is injected in the oil formation under high pressure through an injection well. Movement of the injected water is needed to be traced to test the performance of water flood, investigate unexpected anomalies in flow and verify suspected geological barriers or flow channels, etc. In the present study environmental isotopes and artificial radiotracer (tritium) were used at Fimkassar Oil Field of Oil and Gas Development Company Limited (OGDCL) where water flooding was started in March 1996 in Sakessar formation to maintain its pressure and enhance the oil recovery. Environmental isotopes: /sup 18/O, /sup 2/H and /sup 3/H, and chloride contents were used to determine the breakthrough/transit time and contribution of fresh injected water. Water samples were collected from the injection well, production well and some other fields for reference indices of Sakessar Formation during June 1998 to August 1999. These samples were analyzed for the /sup 18/O, /sup 2/H and /sup 3/H, and chloride contents. Results show that the water of production well is mixture of fresh water and formation water. The fresh water contribution varied from 67% to 80%, while remaining component was the old recharged formation water. This percentage did not change significantly from the time of break-through till the last sampling which indicates good mixing in the reservoir and absence of any quick channel. The initial breakthrough time was 27 months as the fresh water contributed significantly in the first appearance of water in the production well in June 1998. Tritium tracer, which was injected in November 1998, appeared in the production well after 8 months. It show that breakthrough time decreased with the passage of time. /sup 14/C of inorganic carbon in the water in Chorgali and Sakessar Formations was also analyzed which indicates that the water is at least few thousand years old. (author)

  13. Scoping estimates of the LDEF satellite induced radioactivity

    Armstrong, Tony W.; Colborn, B. L.

    1990-01-01

    The Long Duration Exposure Facility (LDEF) satellite was recovered after almost six years in space. It was well-instrumented with ionizing radiation dosimeters, including thermoluminescent dosimeters, plastic nuclear track detectors, and a variety of metal foil samples for measuring nuclear activation products. The extensive LDEF radiation measurements provide the type of radiation environments and effects data needed to evaluate and help resolve uncertainties in present radiation models and calculational methods. A calculational program was established to aid in LDEF data interpretation and to utilize LDEF data for assessing the accuracy of current models. A summary of the calculational approach is presented. The purpose of the reported calculations is to obtain a general indication of: (1) the importance of different space radiation sources (trapped, galactic, and albedo protons, and albedo neutrons); (2) the importance of secondary particles; and (3) the spatial dependence of the radiation environments and effects expected within the spacecraft. The calculational method uses the High Energy Transport Code (HETC) to estimate the importance of different sources and secondary particles in terms of fluence, absorbed dose in tissue and silicon, and induced radioactivity as a function of depth in aluminum.

  14. Designing a program to assess potential induced radioactivity in electron beam sterilization of medical devices

    ISO 11137-1:2006 requires that the potential for induced radioactivity be evaluated for medical devices irradiated with electrons with energy more than 10 MeV. For a manufacturing operation where new devices are being developed, a practical program for making such an evaluation needs to be engrained in the process. A program was developed such that the induced radioactivity evaluation is imbedded in the development of the irradiation process. - Highlights: • A program is described to evaluate induced radioactivity in electron beam. • The program entails evaluation of design prior to manufacturing. • Radiation measurement is done immediately following irradiation. • The instrument has adequate sensitivity for this purpose

  15. Estimation of absorbed gamma dose in air due to natural and artificial radioactivity of soil. Resume of Ph.D thesis

    This is an extended abstract of the Ph. D. thesis devoted to the measurements of air absorbed gamma doses due to natural and artificial radioactivity in soil. It contains a summary of the four chapters of the thesis. The first chapter presents problems related to the measurement of natural and artificial radioactivity coming from soil contamination due to nuclear explosions or nuclear accidents. The natural and artificial radionuclides which usually contaminate the soil are reviewed. The chapter two presents the original contribution of the author in the field of the methods of soil sampling and NaI(Tl) gamma spectrometry analysis of radioactive samples. Also the results of the measurements carried out in 10 counties in Romania are here reported. The natural radionuclides measured were Ra-226, Th-232, and K-40, while the artificial radionuclides were Cs-137 and Cs-134. In the third chapter the radioactivity levels are reported as absorbed air gamma doses due to presence of 137 Cs and 134 Cs in soil. Also here the effective dose equivalents estimated for the population of the 10 counties are presented. In the concluding chapter four a discussion is given concerning the dose levels measured following the Chernobyl nuclear accident as function of time elapsed from the accident and of depth of soil sampling and of soil type. It is shown that the dose levels which affected the population in the studied zones are within the values of radioprotection standards in Romania. These data were used as input to solve the problem of the biological effects of low doses on the population health. (M.I.C.). 7 Figs., 10 Tabs., 73 Refs

  16. Artificial stone dust-induced functional and inflammatory abnormalities in exposed workers monitored quantitatively by biometrics

    Noa Ophir

    2016-03-01

    Full Text Available The manufacture of kitchen and bath countertops in Israel is based mainly on artificial stone that contains 93% silica as natural quartz, and ∼3500 workers are involved in cutting and processing it. Artificial stone produces high concentrations of silica dust. Exposure to crystalline silica may cause silicosis, an irreversible lung disease. Our aim was to screen exposed workers by quantitative biometric monitoring of functional and inflammatory parameters. 68 exposed artificial stone workers were compared to 48 nonexposed individuals (controls. Exposed workers filled in questionnaires, and all participants underwent pulmonary function tests and induced sputum analyses. Silica was quantitated by a Niton XL3 X-ray fluorescence spectrometer. Pulmonary function test results of exposed workers were significantly lower and induced sputa showed significantly higher neutrophilic inflammation compared to controls; both processes were slowed down by the use of protective measures in the workplace. Particle size distribution in induced sputum samples of exposed workers was similar to that of artificial stone dust, which contained aluminium, zirconium and titanium in addition to silica. In conclusion, the quantitation of biometric parameters is useful for monitoring workers exposed to artificial stone in order to avoid deterioration over time.

  17. Destabilization of artificial biomembrane induced by the penetration of tryptophan

    The effect of tryptophan on the membrane stability was studied by using three artificial biological membranes including liposome, Langmuir monolayer and solid supported bilayer lipid membrane (s-BLM) as models. All the results indicate that the penetration of tryptophan can destabilize different artificial biological membranes. The diameter of liposome and the leakage of calcein from liposome increased with the increase of tryptophan concentration because the penetration of tryptophan was beneficial for dehydrating the polar head groups of lipids and the formation of fusion intermediates. π-A isotherms of lecithin on the subphase of tryptophan solution further confirm that tryptophan can penetrate into lipid monolayer and reduce the stability of lipid monolayer. When the concentration of tryptophan increased from 0 to 2 x 10-3 mol L-1, the limiting molecular area of lecithin increased from 110.5 to 138.5 A2, but the collapse pressure of the monolayer decreased from 47.6 to 42.3 mN m-1, indicating the destabilization of lipid monolayer caused by the penetration of tryptophan. The resistance spectra of s-BLM demonstrate that the existence of tryptophan leads to the formation of some defects in s-BLM and the destabilization of s-BLM. The values of electron-transfer resistance and double layer capacitance respectively decreased from 5.765 x 106 Ω and 3.573 x 10-8 F to 1.391 x 106 Ω and 3.340 x 10-8 F when the concentration of tryptophan increased from 0 to 2 x 10-3 mol L-1. Correspondingly, the breakdown voltage of s-BLM decreased from 2.51 to 1.72 V.

  18. Environmental radioactivity. Measurement and monitoring

    The contribution on environmental radioactivity covers the following issues: natural and artificial radioactivity; continuous monitoring of radioactivity; monitoring authorities and measurement; radioactivity in the living environment; radioactivity in food and feeding stuff; radioactivity of game meat and wild-growing mushrooms; radioactivity in mines; radioactivity in the research center Rossendorf.

  19. Reevaluation of induced radioactivity in 10MeV electron-irradiated pepper for public acceptance

    To examine whether or not radioactivity could be produced in black pepper and white pepper with 10MeV electrons, the sample was irradiated with 10MeV electrons from a linear accelerator and its radioactivity was measured by gamma-ray spectrometry and beta-ray counting. The patterns of gamma-ray spectra showed that there was no difference between the irradiated and the non-irradiated samples, suggesting that the induced radioactivity in the irradiated sample was below the detection limit of its induced radioactivity. For further estimation, elemental composition was analyzed and photonuclear reactions which could produce radioactivity in the sample were investigated based on the data already published. Some photonuclear target nuclides in the list were spiked to the sample, being checked in the same way. Although short lived photonuclear products were observed, these radioactivities were found to decrease below the detection limit in a week. It is concluded that the induced radioactivity in the 10MeV electron-irradiated pepper and, hence, its biological effect is far smaller than the natural radioactivity arising from 40K contained in the non-irradiated sample. (author)

  20. A decade of assessment of the natural and artificial radioactivity in feedstuff and food commodities imported and exported by Brazil

    Full text: Natural and artificial radionuclides in feedstuff with concentration levels surpassing the brazilian (CNEN-NN 3.05, January 2005) and international (IAEA 115 Safety Series, 1996 and Codex Alimentarius, 2006) limits are harmless to the human health and an effective control is needed in order to only allow consumption of products presenting radiation levels below limits. Since 1988, after the Chernobyl accident, the Environmental Radiometric Laboratory at the Nuclear and Energy Research Institute, IPEN-CNEN/SP (Instituto de Pesquisas Energeticas e Nucleares), performs, on a regular basis, analysis of potassium-40, cesium-134 and cesium-137 concentrations in feedstuff and food commodities imported and exported by Brazil. The present work covers mostly a decade of results, from 1996 to 2007, assessed from the measurements of almost 2600 samples. The imported Belgium and the exported ones are originated from 14 Brazilian States and 111 regions. Nearly 90 different kinds of feedstuff and food commodities were measured, including condensed milk, milk powder, soy beans, sugar, raw coffee beans, etc. All samples were analyzed by high resolution gamma-spectrometry and the results, compared with brazilian and international limits, released as a technical report. The radioactivity present in all analyzed products was within the international limits, allowing to conclude that consumption of such goods offers no health risk derived from radiation. Potential relationships between the type and the origin of the products exported and imported by Brazil and the radionuclides concentrations are also approached. Finally, all results will contribute to the establishment of a radiometric database for the radionuclides concentrations in the feedstuff and food commodities produced in Brazil. (author)

  1. Preliminary examination of induced radioactivity in pepper by 10 MeV electron irradiation

    β-ray measurement was performed on 10 MeV electron-irradiated black pepper and white pepper with liquid scintillation counter in order to reconfirm the wholesomeness of irradiated foods and present unambiguous data to general consumers concerning about the induced radioactivity in the irradiated foods. In irradiated black pepper no radioactivity other than from natural source, un-irradiated one, was detected. But in irradiated white pepper, it was suggested that induced radioactivity might be detected if the detection method was more improved. (author)

  2. Radioactivity of tobacco leaves and radiation dose induced from smoking.

    Papastefanou, Constantin

    2009-02-01

    The radioactivity in tobacco leaves collected from 15 different regions of Greece and before cigarette production was studied in order to find out any association between the root uptake of radionuclides from soil ground by the tobacco plants and the effective dose induced to smokers from cigarette tobacco due to the naturally occurring primordial radionuclides , such as 226Ra and 210Pb of the uranium series and 228Ra of the thorium series and/or man-made radionuclides, such as 137Cs of Chernobyl origin. Gamma-ray spectrometry was applied using Ge planar and coaxial type detectors of high resolution and high efficiency. It was concluded that the activities of the radioisotopes of radium, 226Ra and 228Ra in the tobacco leaves reflected their origin from the soil by root uptake rather than fertilizers used in the cultivation of tobacco plants. Lead-210 originated from the air and was deposited onto the tobacco leaves and trapped by the trichomes. Potassium-40 in the tobacco leaves was due to root uptake either from soil or from fertilizer. The cesium radioisotopes 137Cs and 134Cs in tobacco leaves were due to root uptake and not due to deposition onto the leaf foliage as they still remained in soil four years after the Chernobyl reactor accident, but were absent from the atmosphere because of the rain washout (precipitation) and gravitational settling. The annual effective dose due to inhalation for adults (smokers) for 226Ra varied from 42.5 to 178.6 microSv/y (average 79.7 microSv/y), while for 228Ra from 19.3 to 116.0 microSv/y (average 67.1 microSv/y) and for 210Pb from 47.0 to 134.9 microSv/y (average 104.7 microSv/y), that is the same order of magnitude for each radionuclide. The sum of the effective doses of the three radionuclides varied from 151.9 to 401.3 microSv/y (average 251.5 microSv/y). The annual effective dose from 137Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4 nSv/y (average 199.3 nSv/y). PMID:19440399

  3. Radioactivity of Tobacco Leaves and Radiation Dose Induced from Smoking

    Constantin Papastefanou

    2009-02-01

    Full Text Available The radioactivity in tobacco leaves collected from 15 different regions of Greece and before cigarette production was studied in order to find out any association between the root uptake of radionuclides from soil ground by the tobacco plants and the effective dose induced to smokers from cigarette tobacco due to the naturally occurring primordial radionuclides , such as 226Ra and 210Pb of the uranium series and 228Ra of the thorium series and/or man-made radionuclides, such as 137Cs of Chernobyl origin. Gamma-ray spectrometry was applied using Ge planar and coaxial type detectors of high resolution and high efficiency. It was concluded that the activities of the radioisotopes of radium, 226Ra and 228Ra in the tobacco leaves reflected their origin from the soil by root uptake rather than fertilizers used in the cultivation of tobacco plants. Lead-210 originated from the air and was deposited onto the tobacco leaves and trapped by the trichomes. Potassium-40 in the tobacco leaves was due to root uptake either from soil or from fertilizer. The cesium radioisotopes 137Cs and 134Cs in tobacco leaves were due to root uptake and not due to deposition onto the leaf foliage as they still remained in soil four years after the Chernobyl reactor accident, but were absent from the atmosphere because of the rain washout (precipitation and gravitational settling. The annual effective dose due to inhalation for adults (smokers for 226Ra varied from 42.5 to 178.6 μSv/y (average 79.7 μSv/y, while for 228Ra from 19.3 to 116.0 μSv/y (average 67.1 μSv/y and for 210Pb from 47.0 to 134.9 μSv/y (average 104.7 μSv/y, that is the same order of magnitude for each radionuclide. The sum of the effective doses of the three radionuclides varied from 151.9 to 401.3 μSv/y (average 251.5 μSv/y. The annual effective dose from 137Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4 nSv/y (average 199.3 nSv/y.

  4. Evaluation of induced radioactivity in 10 MeV electron-irradiated spices

    In order to make clear appreciation to induced radioactivity in the irradiated foods, photonuclear reactions which could produce radioactivity at energies up to 10 MeV were listed up from elemental compositions of black pepper, white pepper, red pepper, ginger and turmeric. The samples were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy and radioactivity was measured. Induced radioactivity could not be detected significantly by gamma-ray spectrometry and beta-ray counting in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H50 according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from 40K contained in the samples. (J.P.N.)

  5. Evaluation of induced radioactivity in 10 MeV electron-irradiated spices

    Furuta, Masakazu; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Katayama, Tadashi; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1993-10-01

    In order to make clear appreciation to induced radioactivity in the irradiated foods, photonuclear reactions which could produce radioactivity at energies up to 10 MeV were listed up from elemental compositions of black pepper, white pepper, red pepper, ginger and turmeric. The samples were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy and radioactivity was measured. Induced radioactivity could not be detected significantly by gamma-ray spectrometry and beta-ray counting in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (J.P.N.).

  6. Artificial sweeteners produce the counterintuitive effect of inducing metabolic derangements.

    Swithers, Susan E

    2013-09-01

    The negative impact of consuming sugar-sweetened beverages on weight and other health outcomes has been increasingly recognized; therefore, many people have turned to high-intensity sweeteners like aspartame, sucralose, and saccharin as a way to reduce the risk of these consequences. However, accumulating evidence suggests that frequent consumers of these sugar substitutes may also be at increased risk of excessive weight gain, metabolic syndrome, type 2 diabetes, and cardiovascular disease. This paper discusses these findings and considers the hypothesis that consuming sweet-tasting but noncaloric or reduced-calorie food and beverages interferes with learned responses that normally contribute to glucose and energy homeostasis. Because of this interference, frequent consumption of high-intensity sweeteners may have the counterintuitive effect of inducing metabolic derangements. PMID:23850261

  7. Studies of muon-induced radioactivity at NuMI

    Boehnlein, David J

    2012-01-01

    The JASMIN Collaboration has studied the production of radionuclides by muons in the muon alcoves of the NuMI beamline at Fermilab. Samples of aluminum and copper are exposed to the muon field and counted on HpGe detectors when removed to determine their content of radioactive isotopes. We compare the results to MARS simulations and discuss the radiological implications for neutrino factories and muon colliders.

  8. Earthquake-induced landslide-susceptibility mapping using an artificial neural network

    Lee, S.; Evangelista, D. G.

    2006-01-01

    The purpose of this study was to apply and verify landslide-susceptibility analysis techniques using an artificial neural network and a Geographic Information System (GIS) applied to Baguio City, Philippines. The 16 July 1990 earthquake-induced landslides were studied. Landslide locations were identified from interpretation of aerial photographs and field survey, and a spatial database was constructed from topographic maps, geology, land cover and terrain mapping units. Factors that influence...

  9. Induced radioactivity in a 4 MW target and its surroundings

    Agosteo, Stefano; Otto, Thomas; Silari, Marco

    2003-01-01

    An important aspect of a future CERN Neutrino Factory is the material activation arising from a 2.2 GeV, 4 MW proton beam striking a mercury target. An estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump was performed by the Monte Carlo hadronic cascade code FLUKA. The aim was both to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which will have to be disposed of after the facility has ceased operation.

  10. Evaluation of induced radioactivity in 10 MeV-electron irradiated spices, (1); [gamma]-ray measurement

    Furuta, Masakazu; Katayama, Tadashi; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Shibata, Setsuko; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1994-02-01

    Black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electrons from a linear accelerator to a dose of 100 kGy and radioactivity was measured in order to estimate induced radioactivity in the irradiated foods. Induced radioactivity could not be detected significantly by [gamma]-ray spectrometry in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list of photonuclear reactions which could produce radioactivity below 10 MeV. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (author).

  11. Exploring thermally induced states in square artificial spin-ice arrays

    Porro, J. M.; Bedoya-Pinto, A.; Berger, A.; Vavassori, P.

    2013-05-01

    We present a methodology to explore experimentally the formation of thermally induced long-range ground-state ordering in artificial spin-ice systems. Our novel approach is based on the thermalization from a square artificial spin-ice array of elongated ferromagnetic nanoislands made of a FeNi alloy characterized by a Curie temperature about 100 K lower than that of Permalloy (Ni81Fe19), which is commonly used for this kind of investigation. The decrease in M(T) when the sample is heated close to its Curie temperature reduces the shape anisotropy barrier of each island and allows us to bring the artificial spin-ice pattern above the blocking temperature of the islands, thus ‘melting’ the spin-ice system, without damaging the sample. The magnetization configuration resulting from the thermal excitation of the islands and the frustrated dipolar interactions among them can be then imaged by magnetic force microscopy or any other kind of magnetic microscopy imaging after cooling down the sample back to room temperature. This thermally induced melting-freezing protocol can be repeated as many times as desired on the same sample and the heating and cooling parameters (max T, heating and cooling rates, number of cycles, application of external fields) varied at will. Thereby, the approach proposed here opens up a pathway to the systematic experimental study of thermally induced frozen states in artificial spin-ice systems, which have been the subject of many recent theoretical studies due to their interesting physical properties but, because of the difficulties in obtaining them in real samples and in a controlled manner, remain experimentally an almost completely unexplored terrain.

  12. Measurement of radioactivity induced by GeV-protons and spallation neutrons using AGS accelerator

    Measurement of radioactivity induced by high-energy protons with energy of 2.83 and 24 GeV and spallation neutrons produced by bombarding a mercury target with the high-energy protons were performed by using the AGS (Alternative Gradient Synchrotron) accelerator at Brookhaven National Laboratory. The samples of boron, carbon, aluminum, iron, copper, niobium, mercury-oxide, lead, bismuth, acrylic resin, SS-316, Inconel-625 and Inconel-718 were irradiated around the mercury target. After the irradiation, the radioactivity of each sample was measured by using HPGe detectors at the cooling time between 2 h and 200 d. In the processing of the measured γ-ray spectra, more than 90 radioactive nucleus were identified, and the radioactivity production data were obtained. This report gives the experimental procedure, the data processing and the experimental results. (author)

  13. Electromagnetically induced transparency using a superconducting artificial atom with optimized level anharmonicity

    Shao, Zhu-Lei; Feng, Zhi-Bo

    2016-04-01

    We propose a theoretical scheme to implement electromagnetically induced transparency (EIT) using an artificial atom of superconducting circuit. Allowed by the selection rule, two kinds of interactions between the atom and driving fields can be obtained, in which we focus on the leakage effect. In terms of dark-state mechanism in generating EIT, the leakage could destroy the EIT considerably. By removing the leakage effect in an optimized three-level atom, we consider a realization of EIT through the technique of density matrix. Furthermore, another effective way to optimize the level anharmonicity is analyzed in a dressing-state method. The scheme could provide a promising approach for experimentally improving EIT with the artificial atoms.

  14. IRACM : A code system to calculate induced radioactivity produced by ions and neutrons

    It is essential to estimate of radioactivity induced in accelerator components and samples bombarded by energetic ion beams and the secondary neutrons of high-energy accelerator facilities in order to reduce the amount of radioactive wastes and to minimize radiation exposure to personnel. A computer code system IRACM has been developed to estimate product nuclides and induced radioactivity in various radiation environments of accelerator facilities. Nuclide transmutation with incident particles of neutron, proton, deuteron, alpha, 12C, 14N, 16O, 20Ne and 40Ar can be computed for arbitrary multi-layer target system in a one-dimensional geometry. The code system consists of calculation modules and libraries including activation cross sections, decay data and photon emission data. The system can be executed in both FACOM-M780 mainframe and DEC workstations. (author)

  15. Induced radioactivity of steel components in industrial flaw inspection with electron accelerators

    The results are presented of experimental investigations of the characteristics of gamma radiation of induced radioactivity of steel components and also of structural members of the accelerator/flaw detector. Semiempirical equations are proposed for determining the holding time of inspected components and the betatron which take into account the focusing distance, exposure time, and braking radiation intensity

  16. Artificial neural network for on-site quantitative analysis of soils using laser induced breakdown spectroscopy

    Nowadays, due to environmental concerns, fast on-site quantitative analyses of soils are required. Laser induced breakdown spectroscopy is a serious candidate to address this challenge and is especially well suited for multi-elemental analysis of heavy metals. However, saturation and matrix effects prevent from a simple treatment of the LIBS data, namely through a regular calibration curve. This paper details the limits of this approach and consequently emphasizes the advantage of using artificial neural networks well suited for non-linear and multi-variate calibration. This advanced method of data analysis is evaluated in the case of real soil samples and on-site LIBS measurements. The selection of the LIBS data as input data of the network is particularly detailed and finally, resulting errors of prediction lower than 20% for aluminum, calcium, copper and iron demonstrate the good efficiency of the artificial neural networks for on-site quantitative LIBS of soils. - Highlights: ► We perform on-site quantitative LIBS analysis of soil samples. ► We demonstrate that univariate analysis is not convenient. ► We exploit artificial neural networks for LIBS analysis. ► Spectral lines other than the ones from the analyte must be introduced

  17. Induced radioactivity of LDEF materials and structural components

    Harmon, B. A.; Laird, C. E.; Fishman, G. J.; Parnell, T. A.; Camp, D. C.; Frederick, C. E.; Hurley, D. L.; Lindstrom, D. J.; Moss, C. E.; Reedy, R. C.; Reeves, J. H.; Smith, A. R.; Winn, W. G.; Benton, E. V.

    1996-01-01

    We present an overview of the Long Duration Exposure Facility (LDEF) induced activation measurements. The LDEF, which was gravity-gradient stabilized, was exposed to the low Earth orbit (LEO) radiation environment over a 5.8 year period. Retrieved activation samples and structural components from the spacecraft were analyzed with low and ultra-low background HPGe gamma spectrometry at several national facilities. This allowed a very sensitive measurement of long-lived radionuclides produced by proton- and neutron-induced reactions in the time-dependent, non-isotropic LEO environment. A summary of major findings from this study is given that consists of directionally dependent activation, depth profiles, thermal neutron activation, and surface beryllium-7 deposition from the upper atmosphere. We also describe a database of these measurements that has been prepared for use in testing radiation environmental models and spacecraft design.

  18. Induced radioactivity evaluation for reference materials by European scientific cooperation

    The global objective of this research is to apply the latest theoretical achievements for calculation of nuclear quantities on the request lists of the current EC projects related to activation (European Activation File) and fusion (European Fusion File, Joint Evaluation File and Fusion Evaluated Nuclear Data Library). The main goal has concerned the (n,p) and (n,α) reaction cross sections, of first importance for prediction of radiation damage in fusion reactor stainless steel. The required development of adequate activation computer codes and data libraries are expected to provide improvement of the following types of nuclear data: - threshold and capture reactions leading to long-lived radionuclides; - other neutron-induced reactions producing the most critical activities in elements ranging from boron to bismuth; - charged-particle emission spectra of neutron-induced reactions and charged-particle induced reactions needed to treat the important sequential (x,n) reactions; - detailed error estimates of critical nuclear data, in order to specify the uncertainty levels of current predictions for radiological properties of potential low-activation materials

  19. Environmental radioactivity in Caithness and Sutherland. Pt. 10: Studies of artificial radioactivity in the coastal environment of Northern Scotland: a review

    This review brings together measurements which have been made over the last 10-15 years of the concentrations of a number of artificial radionuclides in various media in the northern Scottish coastal environment. The radionuclides include 60Co, 90Sr, 134Cs, 137Cs, 238Pu, 239,240Pu and 241Am. The media include nearshore and offshore seawater, beach sand and sediments, seaweeds, winkles, spume, deposits on rocks and soils, sheep faeces and atmospheric deposition. The various radionuclide sources which contribute to the study area are described. Some transfer mechanisms which operate between different media for different radionuclides are discussed, and the radiological significance of the observed radionuclide concentrations is briefly described. (UK)

  20. Application of artificial neural networks on the characterization of radioactive waste drums; Aplicacao de redes neurais artificiais na caracterizacao de tambores de rejeito radioativo

    Potiens Junior, Ademar Jose; Hiromoto, Goro, E-mail: apotiens@ipen.b, E-mail: hiromoto@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-10-26

    The methodology consist of system simulation of drum-detector by Monte Carlo for obtention of counting efficiency. The obtained data were treated and a neural artificial network (RNA) were constructed for evaluation of total activity of drum. For method evaluation measurements were performed in ten position parallel to the drum axis and the results submitted to the RNA. The developed methodology showed to be effective for isotopic characterization of gamma emitter radioactive wastes distributed in a heterogeneous way in a 200 litters drum. The objective of this work as to develop a methodology of analyse for quantification and localization of radionuclides not homogeneous distributed in a 200 liters drum based on the mathematical techniques

  1. A radiation-induced breast cancer following artificial pneumothorax therapy for pulmonary tuberculosis

    A case of radiation-induced breast cancer in a woman who had been fluoroscopied repeatedly for control of pneumothorax for pulmonary tuberculosis 35 years before is reported. The breast tissue presumably received about 136 rads or less in three and a half years. In Japan, both prospective and retrospective surveies following multiple fluoroscopies during artificial pneumothorax collaps therapy have failed to show an increase in the risk of subsequent development of primary breast cancer. The dose given to breast tissues in Japanese patients was generally far less than that in the MacKenzie's series. A radiation-induced breast cancer in Japanese literature has not yet been reported. It seems that the lesser doses may explain the reason of this fact. (auth.)

  2. Influence of ion bombardment induced patterning of exchange bias in pinned artificial ferrimagnets on the interlayer exchange coupling

    Schmalhorst, Jan; Reiss, Guenter; Hoenik, V. [Thin Films and Nanostructures, Department of Physics, Univ. Bielefeld (Germany); Weis, Tanja; Engel, Dieter; Ehresmann, Arno [Institute of Physics and Center for Interdisciplinary Nanostructure Science and Technology, Kassel Univ. (Germany)

    2007-07-01

    Artificial ferrimagnets (AFi) have many applications as, e.g., pinned reference electrodes in magnetic tunnel junctions. It is known that the application of ion bombardment induced magnetic patterning with He ions on a single layer reference electrode of magnetic tunnel junctions is possible. For some applications a combination of ion bombardment induced magnetic patterning and artificial ferrimagnets as a reference electrode is desirable. The effect of ion bombardment induced magnetic patterning on pinned artificial ferrimagnets with a Ru interlayer which is frequently used in magnetic tunnel junctions as well as pinned AFis with a Cu interlayer has been tested. Special attention has been given to the question whether the antiferromagnetic interlayer exchange coupling can withstand the ion dose necessary to turn the exchange bias.

  3. Artificial radioactivity in edible parts of giant clam mollusc from Mururoa atoll from 1967 to 1990. Health physics aspect

    Radionuclides concentration by giant clams is associated with feeding habit. It's also a main food for polynesian atolls inhabitants, elsewhere than Mururoa island because this mollusc is not consumed like all the other fishery products from this atoll lagoon. Nevertheless measurements of ten artificial radionuclides are performed in edible parts of giant clams fished from Mururoa lagoon since the beginning of nuclear tests. The decay of radionuclides concentration is described versus time. To go further on we have computed the dose-equivalent for internal exposure of an eventual giant clams eater. It is estimated that the resulting risk of malignancy is below than 1 per 10 000

  4. Study on patient-induced radioactivity during proton treatment in hengjian proton medical facility.

    Wu, Qingbiao; Wang, Qingbin; Liang, Tianjiao; Zhang, Gang; Ma, Yinglin; Chen, Yu; Ye, Rong; Liu, Qiongyao; Wang, Yufei; Wang, Huaibao

    2016-09-01

    At present, increasingly more proton medical facilities have been established globally for better curative effect and less side effect in tumor treatment. Compared with electron and photon, proton delivers more energy and dose at its end of range (Bragg peak), and has less lateral scattering for its much larger mass. However, proton is much easier to produce neutron and induced radioactivity, which makes radiation protection for proton accelerators more difficult than for electron accelerators. This study focuses on the problem of patient-induced radioactivity during proton treatment, which has been ignored for years. However, we confirmed it is a vital factor for radiation protection to both patient escort and positioning technician, by FLUKA's simulation and activation formula calculation of Hengjian Proton Medical Facility (HJPMF), whose energy ranges from 130 to 230MeV. Furthermore, new formulas for calculating the activity buildup process of periodic irradiation were derived and used to study the relationship between saturation degree and half-life of nuclides. Finally, suggestions are put forward to lessen the radiation hazard from patient-induced radioactivity. PMID:27423927

  5. Remineralization efficiency of bioactive glass on artificially induced carious lesion an in-vitro study

    Sai Sathya Narayana

    2014-01-01

    Full Text Available Objectives: The objective of this study is to investigate the efficacy of bioactive glass containing product on remineralization of artificial induced carious enamel lesion and to compare its efficiency with other remineralization products using an in-vitro pH cycling method. The null hypothesis tested was bioactive glass has no effect on enamel remineralization. Materials and Methods: A total of 20 enamel samples of human molar teeth were subjected to artificial caries lesion formation using pH cycling method and was verified using high resolution scanning electron microscope (HRSEM. Each demineralized sample was then divided into five test groups each containing twenty. Group A - Bioactive glass (SHY-NM, Group B - Fluoride tooth paste (Amflor, Group C - CPP-ACP (Tooth mousse, Group D - CPP-ACPF (Tooth mousse plus, Group E - control. All the test groups were exposed to the pH cycling regime, the remineralizing agents were applied for 10 min except control. After 10 days period, the entire test groups were evaluated with HRSEM and quantitative assessment by energy dispersive X-ray spectroscopy. The obtained data was analyzed statistically using one-way ANOVA, Student′s t-test and Tukey′s multiple comparison tests. P ≤ 0.05 was considered to be significant. Results: Rejection of the null hypothesis and highlights the concept of biomimetic bioactive glass as an effective remineralizing agent. Clinical Relevance: To focus on the importance of minimal invasive treatment on incipient carious lesion by remineralization.

  6. Earthquake-induced landslide-susceptibility mapping using an artificial neural network

    S. Lee

    2006-01-01

    Full Text Available The purpose of this study was to apply and verify landslide-susceptibility analysis techniques using an artificial neural network and a Geographic Information System (GIS applied to Baguio City, Philippines. The 16 July 1990 earthquake-induced landslides were studied. Landslide locations were identified from interpretation of aerial photographs and field survey, and a spatial database was constructed from topographic maps, geology, land cover and terrain mapping units. Factors that influence landslide occurrence, such as slope, aspect, curvature and distance from drainage were calculated from the topographic database. Lithology and distance from faults were derived from the geology database. Land cover was identified from the topographic database. Terrain map units were interpreted from aerial photographs. These factors were used with an artificial neural network to analyze landslide susceptibility. Each factor weight was determined by a back-propagation exercise. Landslide-susceptibility indices were calculated using the back-propagation weights, and susceptibility maps were constructed from GIS data. The susceptibility map was compared with known landslide locations and verified. The demonstrated prediction accuracy was 93.20%.

  7. Induced nest spawning and artificial hatching of the fertilized eggs of mudskipper, Boleophthalmus pectinirostris

    HONG Wanshu; ZHANG Qiyong

    2004-01-01

    In this study, nest spawning was successfully induced by exogenous hormone injections and seawater flow stimulation, and optimum condition for hatching fertilized eggs of burrow fish mudskipper, Boleophthalmus pectinirostris, was searched. Apart from spawning inside the nests, females also spawned outside the nests. The percentages of spawned nests were 8.0% to 24.2%. Most eggs were observed adhered to the inner wall of the top half of the nest. Fertilization rates of the nest-spawned eggs varied from 17.3% to 80.8%. Females could spawn after being artificially confined inside the nests with males at ratios of 1:1 or 1:2, but the spawned eggs were not fertilized. Mean hatching rates of artificially fertilized eggs incubated in round plastic buckets were 32.7%-70.6%, and in the net cages, were 4.2%-20.5%, respectively. Mean hatching rates of nest- fertilized eggs incubated in the round plastic buckets were 33.6%-76.3%, and in the net cages, were 5.9%-25.2%. Results showed that round bucket incubation was the best way for hatching fertilized eggs of mudskipper. Keeping the hatching seawater flowing is an important way for increasing the hatching rates of the mudskipper fertilized eggs.

  8. Monitoring of mining-induced ambient radioactivity. 11th expert meeting on ambient radioactivity monitoring, held on 28/29 March 2000 at Schlema

    This 11th expert meeting was the first exclusively devoted to aspects of monitoring mining-induced ambient radioactivity, and therefore was held 'on site', in the formerly important uranium mining area of Schlema. The meeting was organised by the Federal Radiation Protection Office (BfS) on behalf of the Federal Ministry of Environment, Nature Conservation and Reactor Safety (BMU). (orig./CB)

  9. Development of the two-phase flow induced force fluctuation predictive tool using artificial void signal

    In this study, fluctuating force acting on pipe turning section due to two-phase flow is considered. A novel tool to predict upward two-phase flow induced force fluctuations is developed. In order to eliminate tool's dependencies on experimental measurement input, creation of artificial void signal (AVS) was considered by carefully analyzing area-averaged void fraction properties, including probability density and frequency spectra from 36 flow conditions. Generated AVS was successfully coupled with the predictive tool, and as a result, it is capable of predicting fluctuating force magnitude and dominant force frequency from the inlet superficial velocities alone. The tool is applicable for small inner diameter pipe (<∼10 cm) consist of 0-90 degree turning element, and covers two-phase flow regime up to churn-turbulent flow. (author)

  10. DCHAIN-SP 2001: High energy particle induced radioactivity calculation code

    Kai, Tetsuya; Maekawa, Fujio; Kasugai, Yoshimi; Takada, Hiroshi; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kosako, Kazuaki [Sumitomo Atomic Energy Industries, Ltd., Tokyo (Japan)

    2001-03-01

    For the purpose of contribution to safety design calculations for induced radioactivities in the JAERI/KEK high-intensity proton accelerator project facilities, the DCHAIN-SP which calculates the high energy particle induced radioactivity has been updated to DCHAIN-SP 2001. The following three items were improved: (1) Fission yield data are included to apply the code to experimental facility design for nuclear transmutation of long-lived radioactive waste where fissionable materials are treated. (2) Activation cross section data below 20 MeV are revised. In particular, attentions are paid to cross section data of materials which have close relation to the facilities, i.e., mercury, lead and bismuth, and to tritium production cross sections which are important in terms of safety of the facilities. (3) User-interface for input/output data is sophisticated to perform calculations more efficiently than that in the previous version. Information needed for use of the code is attached in Appendices; the DCHAIN-SP 2001 manual, the procedures of installation and execution of DCHAIN-SP, and sample problems. (author)

  11. The extreme Rhone River flood of December 2003 (south east France) - Consequences on the translocation of artificial radioactive contaminants onto the flooded areas

    Full text: In recent years, great progress has been made in reducing the direct emission of artificial radioactivity and other contaminants into the environment from industrial sources. However the transport and fate of previously-released pollutants is still of great concern. In particular, it is now recognized that certain natural sinks, such as soils and deposits of sediment in streams, rivers and oceans, can entrain the contaminants for long periods of time, only to serve as sources of contamination at some later date. Such a phenomenon was first observed in the Irish Sea after sharp decreases in releases from the spent fuel reprocessing plant in Sellafield. In rivers, one of the primary mechanisms for the remobilization of contaminated deposits is thought to be major flood events. As a result of climate change, floods have become more abundant and more destructive in many regions of the globe including Europe. Then substantial changes in risk of translocation of sediments and associated contaminants onto flooded areas is expected. At the beginning of December 2003 an exceptional meteo climatic event led to an extreme Rhone River flood that flooded almost 500 km2 of the low Rhone valley. Flooding waters entrained a large amount of sediments that have deposited on agricultural soils and urban areas. Therefore particle reactive contaminants such as radionuclides may have been partly translocated from the River onto a large terrestrial area through remobilisation of contaminated fluvial sediments. The soils of the low Rhone valley are labelled with 2000 Bq m-2 for 137Cs, 50 Bq m-2 for 239+240Pu and 1.5 Bq m-2 for 238Pu as mean values. Based on our previous studies we estimate than radioactive inputs onto flooded areas might reach about 500 Bq m-2 for 137Cs. Nevertheless, a great spatial heterogeneity is expected depending on both the mass and nature of the sedimentary deposits. Several field cruises were performed until February 2004 to estimate the spatial

  12. The extreme Rhone River flood of December 2003 (South East France) - Consequences on the translocation of artificial radioactive contaminants onto the flooded areas

    Full text: In recent years, great progress has been made in reducing the direct emission of artificial radioactivity and other contaminants into the environment from industrial sources. However the transport and fate of previously-released pollutants is still of great concern. In particular, it is now recognized that certain natural sinks, such as soils and deposits of sediment in streams, rivers and oceans, can entrain the contaminants for long periods of time, only to serve as sources of contamination at some later date. Such a phenomenon was first observed in the Irish Sea after sharp decreases in releases from the spent fuel reprocessing plant in Sellafield. In rivers, one of the primary mechanisms for the remobilization of contaminated deposits is thought to be major flood events. As a result of climate change, floods have become more abundant and more destructive in many regions of the globe including Europe. Then substantial changes in risk of translocation of sediments and associated contaminants onto flooded areas is expected. At the beginning of December 2003 an exceptional meteo climatic event led to an extreme Rhone River flood that flooded almost 500 km2 of the low Rhone valley. Flooding waters entrained a large amount of sediments that have deposited on agricultural soils and urban areas. Therefore particle reactive contaminants such as radionuclides may have been partly translocated from the River onto a large terrestrial area through remobilisation of contaminated fluvial sediments. The soils of the low Rhone valley are labelled with 2000 Bq m-2 for 137Cs, 50 Bq m-2 for 239+240Pu and 1.5 Bq m-2 for 238Pu as mean values. Based on our previous studies we estimate than radioactive inputs onto flooded areas might reach about 500 Bq m-2 for 137Cs. Nevertheless, a great spatial heterogeneity is expected depending on both the mass and nature of the sedimentary deposits. Several field cruises were performed until February 2004 to estimate the spatial

  13. Induced radioactivities and cross section measurements of the 14 MeV irradiated molybdenum foils

    The radioactivities of 14 MeV neutron irradiated Molybdenum foils have been measured for comparison exercise conducted by the IAEA Nuclear Data Section. The spectra of the characteristic gamma-rays emitted as a result of the induced radioactivity were taken with a Ge(Li) detector and an Intrinsic Germanium detector. The cross sections for the reaction 92Mo(n,np)91mNb, 95Mo(n,p)95Nb and 98Mo(n,α)95Zr have been determined using the information provided by the IAEA on the irradiation time, total fluence and masses of the irradiated foils. The activation cross sections determined from the present measurements have been compared with previous work. (author). 8 refs, figs, 3 tabs

  14. Giant Controllable Magnetization Changes Induced by Structural Phase Transitions in a Metamagnetic Artificial Multiferroic.

    Bennett, S P; Wong, A T; Glavic, A; Herklotz, A; Urban, C; Valmianski, I; Biegalski, M D; Christen, H M; Ward, T Z; Lauter, V

    2016-01-01

    The realization of a controllable metamagnetic transition from AFM to FM ordering would open the door to a plethora of new spintronics based devices that, rather than reorienting spins in a ferromagnet, harness direct control of a materials intrinsic magnetic ordering. In this study FeRh films with drastically reduced transition temperatures and a large magneto-thermal hysteresis were produced for magnetocaloric and spintronics applications. Remarkably, giant controllable magnetization changes (measured to be as high has ~25%) are realized by manipulating the strain transfer from the external lattice when subjected to two structural phase transitions of BaTiO3 (001) single crystal substrate. These magnetization changes are the largest seen to date to be controllably induced in the FeRh system. Using polarized neutron reflectometry we reveal how just a slight in plane surface strain change at ~290C results in a massive magnetic transformation in the bottom half of the film clearly demonstrating a strong lattice-spin coupling in FeRh. By means of these substrate induced strain changes we show a way to reproducibly explore the effects of temperature and strain on the relative stabilities of the FM and AFM phases in multi-domain metamagnetic systems. This study also demonstrates for the first time the depth dependent nature of a controllable magnetic order using strain in an artificial multiferroic heterostructure. PMID:26940159

  15. Giant Controllable Magnetization Changes Induced by Structural Phase Transitions in a Metamagnetic Artificial Multiferroic

    Bennett, S. P.; Wong, A. T.; Glavic, A.; Herklotz, A.; Urban, C.; Valmianski, I.; Biegalski, M. D.; Christen, H. M.; Ward, T. Z.; Lauter, V.

    2016-03-01

    The realization of a controllable metamagnetic transition from AFM to FM ordering would open the door to a plethora of new spintronics based devices that, rather than reorienting spins in a ferromagnet, harness direct control of a materials intrinsic magnetic ordering. In this study FeRh films with drastically reduced transition temperatures and a large magneto-thermal hysteresis were produced for magnetocaloric and spintronics applications. Remarkably, giant controllable magnetization changes (measured to be as high has ~25%) are realized by manipulating the strain transfer from the external lattice when subjected to two structural phase transitions of BaTiO3 (001) single crystal substrate. These magnetization changes are the largest seen to date to be controllably induced in the FeRh system. Using polarized neutron reflectometry we reveal how just a slight in plane surface strain change at ~290C results in a massive magnetic transformation in the bottom half of the film clearly demonstrating a strong lattice-spin coupling in FeRh. By means of these substrate induced strain changes we show a way to reproducibly explore the effects of temperature and strain on the relative stabilities of the FM and AFM phases in multi-domain metamagnetic systems. This study also demonstrates for the first time the depth dependent nature of a controllable magnetic order using strain in an artificial multiferroic heterostructure.

  16. Artificial radioactivity in the lower Rhone river. Consequences of floods on activity levels and flow toward the mediterranean

    Despite analytical strategies that today measure ultra-trace levels (i.e., -5 Bq.L-1) of artificial radionuclides, gamma spectrometry of Rhone River samples taken downstream from the nuclear installations located along the Rhone valley regularly detects only 137Cs, 60Co and 241Am. Since dismantlement of the Marcoule-COGEMA reprocessing plant began in 1997, lists of radionuclides in its effluent include 51Cr, 54Mn, 63Ni, 110mAg and 65Zn, released however at levels 10 to 1,000-fold lower than those of 137Cs or 60Co. Today Marcoule effluent is no longer the principal source of 137Cs in the Rhone River basin, as it was in the 1990's. Significant quantities of 137Cs now come from the Rhone watershed itself, from the drainage of soils exposed to atmospheric fallout from the past nuclear tests and from the accident at Chernobyl, and second, from remobilization of previously formed sediment. Our recent research shows that flood events may generate an increase of more than two orders of magnitude in 137Cs activity in downstream Rhone water, because of the input of contaminated particles from both watershed erosion and sediment remobilization. Flood events also generate the flow of high levels of particulate and associated contaminants towards the Mediterranean Sea. Of the 173±22 GBq of 137Cs transferred from the Rhone to the Mediterranean from August 2002 through August 2003, 111±9 GBq went during two floods in September and November 2002: 60% of the annual transfer took place in only 15 days and included almost ten times as much 137Cs activity as is released annually by the reprocessing plant today. The contribution to these flows of re-mobilized Rhone basin sediment inventories contaminated over the past 40 years is under study today. (authors)

  17. Measurement of fertilizers induced radioactivity in tobacco plants and elemental analysis using ICAP–AES

    It is widely accepted that tobacco smoke is the leading cause of lung cancer worldwide. The alpha radioactive content present in tobacco smoke and increasing number of lung cancer cases explain the importance of investigation. The use of different fertilizers may cause alteration in the metabolism of plants causing different response towards uptake of different element and radionuclides. In the present study, the estimation of alpha radioactivity induced by use of different fertilizers in tobacco leaves was made using solid state nuclear track detector (LR-115) to identify the relative presence of radionuclides in the plants. The radon exhalation rates from the tobacco plant were carried out to confirm the presence of radium or emission of radon from plant. The elemental analysis of tobacco plant by inductively coupled argon plasma atomic emission spectrometry provides a way to understand the difference occurred in metabolism caused by the use of fertilizers. The alpha track densities were found to vary with nature of fertilizers added to the soil and an increase was also observed with time. The radon mass exhalation rates in various tobacco plants were found to vary with type of fertilizers used. - Highlights: • The study is related to alpha radioactivity measurements in tobacco plants. • The radon mass exhalation rates in various tobacco plants were also measured. • Study is related to analysis of chemical elements in different fertilized tobacco samples

  18. Computed Tomography-guided Radiofrequency Ablation for Sub-diaphragm Hepatocellular Carcinoma: Safety and Efficacy of Inducing an Artificial Pneumothorax.

    Fujiwara, Hiroyasu; Arai, Yasuaki; Ishii, Hiroaki; Kanazawa, Susumu

    2016-06-01

    We retrospectively evaluated the safety and efficacy of artificial pneumothorax induction to perform computed tomography (CT)-guided radiofrequency ablation (RFA) for sub-diaphragm hepatocellular carcinomas (HCCs). From June 2008 to October 2010 at our institution, 19 HCCs (16 patients) were treated using CT-guided RFA after artificial pneumothorax induction. A 23-G needle was inserted into the liver surface at a site of 2 connected pleurae without lung tissue. After a small amount of air was injected, the pleural space widened, creating a small pneumothorax. Additional air was insufflated via a newly inserted 18-G cannula to raise the lung away from the planned puncture line for RFA. The electrode was then advanced transthoracically. Ablation was performed using a cool-tip electrode with manual impedance control mode. The injected air was then aspirated as much as possible. Artificial pneumothorax was successfully induced in all cases. The average total volume of injected air in each case was 238ml. No artificial pneumothorax-related complication occurred; lung injury occurred in one case during RF electrode insertion. No local progression occurred during follow-up. Recurring HCCs were observed in eight patients. Artificial pneumothorax induction is safe and effective for CT-guided RFA of sub-diaphragm HCCs, which are difficult to locate on US. PMID:27339208

  19. Investigation of induced radioactivity in the CERN Large Electron Positron collider for its decommissioning

    Silari, Marco

    2004-01-01

    The future installation of the Large Hadron Collider in the tunnel formerly housing the Large Electron Positron collider (LEP) required the dismantling of the latter after 11-year operation. As required by the French legislation, an extensive theoretical study was conducted before decommissioning to establish the possible activation paths both in the accelerator and in the four experiments (L3, ALEPH, OPAL and DELPHI) installed around the ring. The aim was to define which areas may contain activated material and which ones would be completely free of activation. The four major sources of activation in LEP, i.e., distributed and localized beam losses, synchrotron radiation and the super-conducting RF cavities, were investigated. Conversion coefficients from unit lost beam power to induced specific activity were established for a number of materials. A similar study was conducted for the four experiments, evaluating the four potential sources of induced radioactivity, namely e**+e **- annihilation events, two-p...

  20. Cosmic-ray induced production of radioactive noble gases in the atmosphere, ground, and seawater

    This paper describes the development of an MCNP6 model and a suite of supporting MATLAB scripts being developed to conduct detailed studies of the radioactive noble gas background activity concentrations resulting from cosmic-neutron-induced reactions in the Earth's atmosphere, in various geologies, and in seawater. Initial results generated using the MCNP6 model and the suite of supporting MATLAB scripts indicate that the cosmic-neutron-induced 133Xe background activity concentrations at a depth of 1 m in a geology representative of the Earth's upper crust and a depth of 5 m in seawater are about 3.48 × 10-1 and 8.49 × 10-7 mBq m-3, respectively. (author)

  1. An artificial neural network approach to laser-induced breakdown spectroscopy quantitative analysis

    The usual approach to laser-induced breakdown spectroscopy (LIBS) quantitative analysis is based on the use of calibration curves, suitably built using appropriate reference standards. More recently, statistical methods relying on the principles of artificial neural networks (ANN) are increasingly used. However, ANN analysis is often used as a ‘black box’ system and the peculiarities of the LIBS spectra are not exploited fully. An a priori exploration of the raw data contained in the LIBS spectra, carried out by a neural network to learn what are the significant areas of the spectrum to be used for a subsequent neural network delegated to the calibration, is able to throw light upon important information initially unknown, although already contained within the spectrum. This communication will demonstrate that an approach based on neural networks specially taylored for dealing with LIBS spectra would provide a viable, fast and robust method for LIBS quantitative analysis. This would allow the use of a relatively limited number of reference samples for the training of the network, with respect to the current approaches, and provide a fully automatizable approach for the analysis of a large number of samples. - Highlights: • A methodological approach to neural network analysis of LIBS spectra is proposed. • The architecture of the network and the number of inputs are optimized. • The method is tested on bronze samples already analyzed using a calibration-free LIBS approach. • The results are validated, compared and discussed

  2. Simulation by using the lattice Boltzmann method of microscopic particle motion induced by artificial cilia

    Alapati, Suresh; Che, Woo Seong; Mannoor, Madhusoodanan; Suh, Yong Kweon

    2016-06-01

    In this paper, we present the results obtained from the simulation of particle motion induced by the fluid flow driven by an array of beating artificial cilia inside a micro-channel. A worm-like-chain model is used to simulate the elastic cilia, and the lattice Boltzmann equation is used to compute the fluid flow. We employ a harmonic force at the extreme tip of each cilium to actuate it. Our simulation methods are first validated by applying them to the motion of a single cilium and a freely falling sphere. After validation, we simulate the fluid flow generated by an array of beating cilia and find that a maximum flow rate is achieved at an optimum sperm number. Next, we simulate the motion of a neutrally buoyant spherical particle at this optimum sperm number by tracking the particle motion with a smoothed profile method. We address the effect of the following parameters on the particle velocity: the gap between cilia and particle, the particle size, the cilia density, and the presence of an array of intermediate particles.

  3. Radiation dose due to neutron-induced residual radioactivities by the atomic bombs in Hiroshima and Nagasaki

    Radiation dose at 1 m above the ground was estimated due to neutron-induced radioactivities by the atomic bombings in Hiroshima and Nagasaki. The dose rate at the hypocenter at 1 min after the bombing was 600 and 400 cGy h-1 in Hiroshima and Nagasaki, respectively, and rapidly decreased with the decay of the main induced radioactivities of relatively short half-lives: 28Al (2.24 min), 56Mn (2.58 h) and 24Na (15.0 h). The infinite cumulative dose after the bombing was 120 and 57 cGy at the hypocenter of Hiroshima and Nagasaki, respectively, and also sharply decreased with the distance from the hypocenter. Considering the results obtained so far, the people who entered into the area less than 1 km from the hypocenter up to 1 weak after the bombing could receive external dose over 1 cGy from neutron-induced radioactivities. (author)

  4. Radioactivity Assessment of Natural and Artificial Radionuclides in Soil Samples from Tha Phae, La-ngu and Thung Wa Districts in Satun Province, Thailand

    Full text: Specific activities of natural (238U, 226Ra, 232Th and 40K) and artificial anthropogenic (137Cs) radionuclides in 65 soil samples collected from Tha Phae, La-ngu and Thung Wa Districts in Satun province have been measured and analyzed. Experimental results were obtained by using a high-purity germanium (HPGe) detector and gamma spectrometry analysis system. Experimental set-up and measurement were carried out at Nuclear and Material Physics Laboratory in Department of Physics Faculty of Science Thaksin University Songkhla Campus. The counting time for each sample was 10,800 seconds or 3 hours. It was found that the soil specific activities ranged from 0.00 to 11608.87 Bq/kg for 40K, 0.00 to 352.57 Bq/kg for 226Ra, 0.00 to 123.28 Bq/kg for 232Th and 0.00 to 16.28 Bq/kg for 137Cs with mean values of 3,248.96 ± 231.32 Bq/kg, 71.35 ± 5.97 Bq/kg, 53.59 ± 2.14 Bq/kg, and 0.68 ± 0.19 Bq/kg, respectively. Furthermore, the results were used to evaluate the absorbed dose rates in air (D), the radium equivalent (Raeq), the external hazard index (Hex) and the annual effective dose rate (AED) for this area. Moreover, the experimental results were compared to the previous data of the Office of Atoms for Peace (OAP). Thailand and global radioactivity measurements and evaluation, including the proposed recommended values the Organization for Economic Cooperation and Development (OECD, 1979) and the United Nations Scientific Committee on the Effects of Atomic Radiation

  5. Radiological considerations on multi-MW targets Part I Induced radioactivity

    Agosteo, S; Silari, M

    2005-01-01

    CERN is designing a Superconducting Proton Linac (SPL) to provide a 2.2GeV, 4MW proton beam to feed facilities like, for example, a future Neutrino Factory or a Neutrino SuperBeam. The material activation in such facilities is an important aspect that has to be taken into account at an early design stage. In particular, the choice of the target has consequences on the induced radioactivity and dose rates in the target itself and in its surroundings. In the present work, the radiological aspects of a stationary target made up of small tantalum pellets are compared to those of a free-surface jet of mercury. An estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump were performed for both targets by the Monte Carlo hadronic cascade code FLUKA. The aim was to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which...

  6. Radioactive Ion Beam Production by Fast-Neutron-Induced Fission in Actinide Targets at EURISOL

    Herrera-Martínez, Adonai

    The European Isotope Separation On-Line Radioactive Ion Beam Facility (EURISOL) is set to be the 'next-generation' European Isotope Separation On-Line (ISOL) Radioactive Ion Beam (RIB) facility. It will extend and amplify current research on nuclear physics, nuclear astrophysics and fundamental interactions beyond the year 2010. In EURISOL, the production of high-intensity RIBs of specific neutron-rich isotopes is obtained by inducing fission in large-mass actinide targets. In our contribution, the use of uranium targets is shown to be advantageous to other materials, such as thorium. Therefore, in order to produce fissions in U-238 and reduce the plutonium inventory, a fast neutron energy spectrum is necessary. The large beam power required to achieve these RIB levels requires the use of a liquid proton-to-neutron converter. This article details the design parameters of the converter, with special attention to the coupled neutronics of the liquid converter and fission target. Calculations performed with the ...

  7. A facility for studying radiative capture reactions induced with radioactive beams at ISAC

    D'Auria, J. M.; Buchmann, L.; Hutcheon, D.; Lipnik, P.; Hunter, D.; Rogers, J.; Helmer, R.; Giesen, U.; Olin, A.; Bricault, P.; Bateman, N.

    The measurement of low energy fusion reactions of importance to nuclear astrophysics scenarios are a prime objective of the physics program of the new ISAC facility, located at TRIUMF in Vancouver, Canada. Intense radioactive beams of 19Ne, 14,15O, 20,21Na, 17,18F and other low Z species with energies in the range of 0.15 to 1.5 MeV/mass unit will be available to measure cross sections and resonance strengths of alpha and proton induced reactions. An important component of the experimental configuration will be a new Recoil Product Detection Facility (RPDF) consisting of a windowless gas target, surrounded by a gamma array, while the recoils are separated from the intense radioactive beam using a Electro-Magnetic Separator (EMS) employing Wien filters. The recoiling reaction products will then be detected using either a Si μ-strip array or a gas filled detector. Using these devices along with coincidence requirements and time-of-flight conditions a background reduction factor of the order of 10 +15 is the present goal.

  8. Programmatic Assessment of Potential Induced Radioactivity in Electron Beam Sterilization of Healthcare Products.

    Smith, Mark; Logar, John; Montgomery, Alan; Vrain, Olivier

    2016-08-01

    ISO 11137-1:2006 Sterilization of Healthcare Products-Radiation requires that the potential for induced radioactivity be evaluated for medical devices irradiated with electrons with energy more than 10 MeV. For a manufacturing operation where new devices are being developed, a practical program for making such an evaluation should be engrained in the process, including the device design phase, where selection of materials can make a difference in the potential for activation to occur as a result of the irradiation process. The program, which is based on general assumptions as to the likely activation processes and generalized process assessments is being implemented in three phases: (1) incorporating materials consideration in the design phase, (2) evaluating potential activation empirically, including measurement at the point of irradiation, and (3) implementing routine procedures for the program, including developing a data base of results for consideration in future design efforts. PMID:27356164

  9. Does ozone enhance the remineralizing potential of nanohydroxyapatite on artificially demineralized enamel? A laser induced fluorescence study

    Srinivasan, Samuelraj; Prabhu, Vijendra; Chandra, Subhash; Koshy, Shalini; Acharya, Shashidhar; Mahato, Krishna K.

    2014-02-01

    The present era of minimal invasive dentistry emphasizes the early detection and remineralization of initial enamel caries. Ozone has been shown to reverse the initial demineralization before the integrity of the enamel surface is lost. Nano-hydroxyapatite is a proven remineralizing agent for early enamel caries. In the present study, the effect of ozone in enhancing the remineralizing potential of nano-hydroxyapatite on artificially demineralized enamel was investigated using laser induced fluorescence. Thirty five sound human premolars were collected from healthy subjects undergoing orthodontic treatment. Fluorescence was recorded by exciting the mesial surfaces using 325 nm He-Cd laser with 2 mW power. Tooth specimens were subjected to demineralization to create initial enamel caries. Following which the specimens were divided into three groups, i.e ozone (ozonated water for 2 min), without ozone and artificial saliva. Remineralization regimen was followed for 3 weeks. The fluorescence spectra of the specimens were recorded from all the three experimental groups at baseline, after demineralization and remineralization. The average spectrum for each experimental group was used for statistical analysis. Fluorescence intensities of Ozone treated specimens following remineralization were higher than that of artificial saliva, and this difference was found to be statistically significant (Plaser induced fluorescence was found to be effective in assessing the surface mineral changes in enamel. Ozone can be considered an effective agent in reversing the initial enamel caries there by preventing the tooth from entering into the repetitive restorative cycle.

  10. Benchmark experiments of fusion neutron induced gamma-ray radioactivity in various structural materials

    The fusion reactor inventory code FISPACT, together with the European Activation File EAF, is the European reference software for calculating the neutron-induced activation of fusion reactor relevant materials. Experimental verifications (benchmarks) of the code predictions have been performed at ENEA Frascati by means of an irradiation facility consisting of a D-T neutron generator and a moderator/reflector structure which is employed to mimic the neutron spectrum at the a fusion device first wall. Various materials (vanadium alloy, SiC, AlSI 316, martensitic steel F82H, copper, tungsten, iron, niobium), candidates to e used in a fusion reactor, have been exposed to neutrons produced in the facility (about 109 n x cm-2 x s-1) and the short and medium-lived induced radioactivity has been measured by gamma-ray spectroscopy. The experimental results have been used to validate the inventory code FISPACT, the physical database EAF, including its uncertainty predictions, and the composition of the material irradiated in particular for its minor elements and impurities. The comparison between calculated (C) and experimental results (E) is reported as C/E values and shows a satisfactory agreement for almost all radionuclides. Radionuclides for which there is not agreement between calculations and experiments are also discussed and an analysis of the causes of the lack of agreement is carried out. (author)

  11. Background studies: human-induced effects on the evolution of shallow land burial sites for radioactive waste disposal

    This report presents the results of a programme of background research on the human-induced effects on the long term evolution of shallow disposal sites for low level radioactive wastes. The work is intended to support development and use of the TIME2 simulation code. Within the context of climatic change up to the next glacial maximum three areas are addressed: planning and legislative control over site usage, biosphere state changes and intrusion. An appendix presents a discussion of some planning aspects of radioactive waste disposal. (author)

  12. Psychologically induced cooling of a specific body part caused by the illusory ownership of an artificial counterpart

    Moseley, G. Lorimer; Olthof, Nick; Venema, Annemeike; Don, Sanneke; Wijers, Marijke; Gallace, Alberto; Spence, Charles

    2008-01-01

    The sense of body ownership represents a fundamental aspect of our self-awareness, but is disrupted in many neurological, psychiatric, and psychological conditions that are also characterized by disruption of skin temperature regulation, sometimes in a single limb. We hypothesized that skin temperature in a specific limb could be disrupted by psychologically disrupting the sense of ownership of that limb. In six separate experiments, and by using an established protocol to induce the rubber hand illusion, we demonstrate that skin temperature of the real hand decreases when we take ownership of an artificial counterpart. The decrease in skin temperature is limb-specific: it does not occur in the unstimulated hand, nor in the ipsilateral foot. The effect is not evoked by tactile or visual input per se, nor by simultaneous tactile and visual input per se, nor by a shift in attention toward the experimental side or limb. In fact, taking ownership of an artificial hand slows tactile processing of information from the real hand, which is also observed in patients who demonstrate body disownership after stroke. These findings of psychologically induced limb-specific disruption of temperature regulation provide the first evidence that: taking ownership of an artificial body part has consequences for the real body part; that the awareness of our physical self and the physiological regulation of self are closely linked in a top-down manner; and that cognitive processes that disrupt the sense of body ownership may in turn disrupt temperature regulation in numerous states characterized by both. PMID:18725630

  13. Does Artificial Ascites Induce the Heat-Sink Phenomenon during Percutaneous Radiofrequency Ablation of the Hepatic Subcapsular Area?: an in vivo Experimental Study Using a Rabbit Model

    Kim, Young-sun; Rhim, Hyunchul; Choi, Dongil; Lim, Hyo K.

    2009-01-01

    Objective To evaluate the effect of the heat-sink phenomenon induced by artificial ascites on the size of the ablation zone during percutaneous radiofrequency (RF) ablation of the hepatic subcapsular area in an in vivo rabbit model. Materials and Methods A total of 21 percutaneous rabbit liver RF ablations were performed with and without artificial ascites (5% dextrose aqueous solution). The rabbits were divided into three groups: a) control group (C, n = 7); b) room temperature ascites group...

  14. Characteristics of radioactivities induced in aluminum alloys and the effects due to those major and minor components

    In order to search the usefulness of aluminum alloys as a material for an accelerator and its surrounding apparatus, the characteristics of radioactivities induced in several aluminum alloys (AA 1230, AA 2219, JIS 5052, AA 6063 and AA 7079) and stainless steel (SUS 304) irradiated for a long time with high energy bremsstrahlung have been studied fundamentally and compared with each other. After the concentrations of major alloying elements and impurities in the above samples were determined by means of photon-activation, proton-activation and emission spectrochemical analyses, they were irradiated with 30 and 200 MeV bremsstrahlung. As the results, it was proved that the intensities of radioactivities induced in the aluminum alloys are greatly affected by those major and minor components, but are remarkably lower than that in the stainless steel. (author)

  15. Analysis of Correlation Between Urinal Excretion Ratio of Radioactive Iodine and Daily Urinal Excretion Volume

    Internal exposure to radionuclide results from depositing of radioactive substance within human body and is called intra-body exposure as well. Radioactive substance may find its way into human body via nose, mouth or skin and internal exposure to radionuclide is rarely ascribable to radioactive substance deposited through skin. Radioactive substances deposited in human tissues or organs do not stay there for good. Instead, they are transferred to other tissues, organs or excreted by sweat, excrements, urine and breath. However, natural excretion has its limits in terms of safeguarding human body actively against radioactive exposure. When radionuclide is deposited in human organs or tissues, diuretic or evacuant is used to induce excrements or urine to increase removal and discharging of radionuclide artificially, thereby reducing internal exposure. Therefore, we have attempted to propose an optimum approach to removing and excreting radioactive iodine by analyzing the correlation among the radioactive iodine intake ratio, daily urinal excretion ratio and volume

  16. Analysis of Correlation Between Urinal Excretion Ratio of Radioactive Iodine and Daily Urinal Excretion Volume

    Kim, Junghoon; Whang, Jooho [Kyunghee Univ., Yongin (Korea, Republic of); Kim, Teaman [The Korea Institute of Nuclear Safety, Taejon (Korea, Republic of)

    2006-07-01

    Internal exposure to radionuclide results from depositing of radioactive substance within human body and is called intra-body exposure as well. Radioactive substance may find its way into human body via nose, mouth or skin and internal exposure to radionuclide is rarely ascribable to radioactive substance deposited through skin. Radioactive substances deposited in human tissues or organs do not stay there for good. Instead, they are transferred to other tissues, organs or excreted by sweat, excrements, urine and breath. However, natural excretion has its limits in terms of safeguarding human body actively against radioactive exposure. When radionuclide is deposited in human organs or tissues, diuretic or evacuant is used to induce excrements or urine to increase removal and discharging of radionuclide artificially, thereby reducing internal exposure. Therefore, we have attempted to propose an optimum approach to removing and excreting radioactive iodine by analyzing the correlation among the radioactive iodine intake ratio, daily urinal excretion ratio and volume.

  17. Evaluation of a risk communication approach for maintenance staff working with induced radioactivity in medical linear accelerators

    In order to promote consensus building on decommissioning operation rules for medical linear accelerators in Japan, we carried out a risk communication (RC) approach mainly providing knowledge for maintenance staff regarding induced radioactivity. In February 2012, we created a booklet (26 pages) to present an overview of the amended law, the mechanism and the distribution of induced radioactivity showing the actual radiation dose rate around a linear accelerator and actual exposure doses to staff. In addition, we co-sponsored a seminar for workers in this field organized by the Japan Medical Imaging and Radiological Systems Industries Association to explain the contents of this booklet, and answer questions regarding induced radioactivity of linear accelerators as an RC program. As a result, the understanding of staff regarding the regulations on maximum X-ray energy on linear accelerators (P<0.05), and the outline of clearance systems (P<0.01), were facilitated by RC. In addition, we found that about 70% of maintenance staff considered that the cooling time for decommissioning operation depended on the situation. Our RC approach suggests that consensus building should be used to make rules on decommissioning operations for linear medical accelerators. (author)

  18. Results 2005 of the surveillance of the artificial radioactivity levels of aquatic ecosystems in the basin of Seine-Normandy. Riviere 2005

    Set up in 2004 by the A.C.R.O. the citizens network of radioecological surveillance, information and evaluation (R.I.V.I.E.R.E.) aims at making a follow-up of the radioactive contamination of the aquatic ecosystems on the scale of the Seine-Normandy pond: from Nogent-on-Seine to La Hague and from the Mont-Saint-Michel to the Treport. The peculiarity of this network, which also makes its strength is to associate strictly all those who wish to appropriate the knowledge of the radioactivity levels around to them. With R.I.V.I.E.R.E., the citizen is at the same moment an author and an actor of the surveillance of his environment as his information. An approach defended by the A.C.R.O. since about 20 years and which has no equivalent anywhere else. This project has four main objectives: to know the levels and the tendencies of the present radioactivity in the main aquatic ecosystems of the Seine-Normandy widened pond, and so feed a data base including more than 3000 analysis (limited to the gamma radioactivity and to the tritium); to allow the citizens who put a lot to appropriate the knowledge and the indispensable references to understand the radioactivity of their environment; to establish a support in the public information about the radioactivity in environment; to supply data to the national network of measures of the radioactivity in environment, network established by decree recently and in charge of the evaluation of the public exposure. (N.C.)

  19. Snag characteristics and dynamics following natural and artificially induced mortality in a managed loblolly pine forest.

    Zarnoch, Stanley J. [USDA Forest Service; Vukovich, Mark A. [USDA Forest Service; Kilgo, John C. [USDA Forest Service; Blake, John I. [USDA Forest Service

    2013-06-10

    A 14-year study of snag characteristics was established in 41- to 44-year old loblolly pine (Pinus taeda L.) stands in southeastern USA. During the initial 5.5 years, no stand manipulation or unusually high-mortality events occurred. Afterwards, three treatments were applied consisting of trees thinned and removed, trees felled and not removed, and artificial creation of snags produced by girdling and herbicide injection. The thinned treatments were designed to maintain the same live canopy density as the snag-created treatment, disregarding snags that remained standing.We monitored snag height, diameter, density, volume, and bark percentage; the number of cavities was monitored in natural snags only. During the first 5.5 years, recruitment and loss rates were stable, resulting in a stable snag population. Large snags (≥25 cm diameter) were common, but subcanopy small snags (10 to <25 cm diameter) dominated numerically. Large natural snags survived (90% quantile) significantly longer (6.0–9.4 years) than smaller snags (4.4–6.9 years). Large artificial snags persisted the longest (11.8 years). Cavities in natural snags developed within 3 years following tree death. The mean number of cavities per snag was five times greater in large versus small snags and large snags were more likely to have multiple cavities, emphasizing the importance of mature pine stands for cavity-dependent wildlife species.

  20. Natural radioactivity contents in tobacco and radiation dose induced from smoking

    One of the causative factors for cancer-inducing mechanisms in humans is radioactive elements present in tobacco leaves used in the manufacture of cigarettes. Smoking of tobacco and its products increases the internal intake and radiation dose due to naturally occurring radionuclides that are considered to be one of the most significant causes of lung cancer. In this work, different commercial types of cigarettes, cigar and moassel were collected from market. Naturally occurring radionuclides 226Ra and 214Bi (238U series), 228Ac and 228Ra (232Th series), 40K and man-made 137Cs were measured in tobacco using gamma-ray spectrometer. Results show that the average concentrations of 238U, 232Th and 40K were 4.564, 3.940 and 1289.53 Bq kg-1, respectively. This reflects their origin from the soil by root uptake and fertilisers used in the cultivation of tobacco plants. Concentration of 137Cs was 0.348 Bq kg-1 due to root uptake or deposition onto the leaf foliage. For smokers, the annual effective dose due to inhalation of 238U varied from 49.35 to 139.40 μSv-1 (average 104.27 μSv y-1), while of 232Th from 23.86 to 111.06 μSv y -1 (average 65.52 μSv y-1). The annual effective dose resulting from 137Cs was varied from 10.96 to 24.01 nSv y-1 (average 19.41 nSv y-1). (authors)

  1. Studies of ionising radiation induced bystander effects in 3D artificial tissue system and applications for radiation protection

    The universality of the target theory of radiation-induced effects is challenged by observations on non-targeted effects such as bystander effects. Essential features of non-targeted effects are that they do not require direct nuclear exposure by radiation and they are particularly significant at low doses. This new evidence suggests a need for a new paradigm in radiation biology. The new paradigm should cover both the classical (targeted) and the non-targeted effects. The bystander effect cannot be comprehensively explained on the basis of a single cell reaction. It is well known that an organism is composed of different cell types that interact as functional units in a way to maintain normal tissue function. Therefore the radiation response is not simply the sum of cellular responses as assumed in classical radiobiology, predominantly from studies using cell cultures. Experimental models, which maintain tissue-like intercellular cell signalling and 3D structure, are essential for proper understanding of the bystander effect. Our work relates to experimentation with novel 3D artificial human tissue systems available from MatTek Corporation (Boston, USA). Air-liquid interface culture technique is used to grow artificial tissues, which allow to model conditions present in vivo. The Gray Cancer Institute (Northwood, UK) charged particle microbeam was used to irradiate tissue samples in a known pattern with a known number of 3He2+ particles or protons. After irradiation, the tissues models were incubated for 3 days, fixed in 10 % NBF, paraffin embedded and then sliced into 5 μm histological sections located at varying distances from the plane of the irradiated cells. We studied in situ apoptosis and markers of differentiation. Significantly elevated bystander induced apoptosis was observed with 3'-OH DNA end-labelling based technique in 3D artificial tissue systems. Our results also suggested an importance of proliferation and differentiation status for bystander

  2. Artificial granularity in two-dimensional arrays of nanodots fabricated by focused-electron-beam-induced deposition

    Porrati, F; Sachser, R; Huth, M [Physikalisches Institut, Goethe-Universitaet, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main (Germany); Strauss, M [Max-Planck-Institut fuer Biophysik, Max-von-Laue-Strasse 3, D-60438 Frankfurt am Main (Germany); Andrusenko, I; Gorelik, T; Kolb, U [Institut fuer Physikalische Chemie, Johannes Gutenberg-Universitaet Mainz, Welderweg 11, D-55099 Mainz (Germany); Bayarjargal, L; Winkler, B [Institut fuer Geowissenschaften, Abt. Kristallographie, Goethe-Universitaet, Altenhoeferallee 1, D-60438 Frankfurt am Main (Germany)

    2010-09-17

    We have prepared 2D arrays of nanodots embedded in an insulating matrix by means of focused-electron-beam-induced deposition using the W(CO){sub 6} precursor. By varying the deposition parameters, i.e. the electron beam current and energy and the raster constant, we obtain an artificial granular material with tunable electrical properties. The analysis of the temperature dependence of the conductivity and of the current-voltage characteristic suggests that the transport mechanism is governed by electron tunneling between artificial grains. In order to understand the nature of the granularity and thus the microstructural origin of the electronic transport behavior, we perform TEM and micro-Raman investigations. Independent of the deposition parameters, TEM measurements show that the dots are constituted of amorphous tungsten carbide clusters embedded in an amorphous carbonaceous matrix. Micro-Raman spectra show two peaks, around 690 and 860 cm{sup -1} associated with the W-C stretching modes. Higher frequency peaks give information on the composition of the matrix. In particular, we measure a peak at about 1290 cm{sup -1}, which is associated with sp{sup 3} carbon bonds. Furthermore we detect the so-called D and G peaks, at about 1350 and 1560 cm{sup -1}, associated with the vibration modes of the sp{sup 2} carbon bonds. The analysis of the position of the peaks and of their relative intensity suggests that the composition of the matrix is between nanocrystalline graphite and amorphous carbon.

  3. Analysis of micro-composition of biological tissue by means of induced radioactivity

    Tobias, C.A.; Dunn, R.W.

    1948-05-24

    The use of radioactive isotopes as tracers promises a wealth of information regarding the biochemical role of most elements and their components. Usually a radioactive sample of the element to be studied is administered to the plant or animal in a convenient form, and its distribution and rate of exchange are determined in later assays. This technique has, however, certain limitations, two of which will be discussed here: (1) radioactive isotopes are not generally useful for measurements of the concentration of elements in the body or its parts. They can be used only to give a measure of the rate of exchange of the elements and (2) the use of radioactive isotopes for tracer experiments requires that the radiation dose delivered to the tissue should be small in order not to disturb normal biological function.

  4. The electrical charging of inactive aerosols in high ionised atmosphere, the electrical charging of artificial beta radioactive aerosols; Le processus de charge electrique: des aerosols non radioactifs en milieu fortement ionise, des aerosols radioactifs artificiels emetteurs beta

    Gensdarmes, F

    2000-07-01

    The electrical properties of aerosols greatly influence their transport and deposition in a containment. In a bipolar ionic atmosphere, a neutral electric charge on aerosols is commonly assumed. However, many studies report a different charge distribution in some situations, like highly ionised atmosphere or in the case of radioactive aerosols. Such situations could arise from a hypothetical accident in a nuclear power plant. Within the framework of safety studies which are carried out at IPSN, our aims were the study of electrical properties of aerosols in highly ionised atmosphere, and the study of artificial radioactive aerosols, in order to suggest experimental validation of available theories. For this purpose, we designed an experimental device that allows us to measure non-radioactive aerosol charge distribution under high gamma irradiation, up to 10{sup 4} Gy/h. With our experimental device we also studied the properties of small ions in the medium. Our results show a variation of the charge distribution in highly ionised atmosphere. The charge increases with the dose of gamma ray. We have related this variation with the one of the small ions in the gases, according to theoretical prediction. However, the model overestimates slightly our experimental results. In the case of the radioactive aerosols, we have designed an original experimental device, which allows us to study the charge distribution of a {sup 137}Cs aerosol. Our results show that the electric charging of such aerosols is strongly dependent on evolution parameters in a containment. So, our results underline a great enhancement of self-charging of particles which are sampled in a confined medium. Our results are qualitatively in agreement with the theoretical model; nevertheless the latter underestimates appreciably the self-charging, owing to the fact that wall effects are not taken into account. (author)

  5. Induced artificial androgenesis in common tench, Tinca tinca (L., using common carp and common bream eggs

    Dariusz Kucharczyk

    2014-03-01

    Full Text Available This study presents artificial induction using tench eggs, Tinca tinca (L., of androgenetic origin. The oocytes taken from common bream, Abramis brama (L. and common carp, Cyprinus carpio L. were genetically inactivated using UV irradiation and then inseminated using tench spermatozoa. Androgenetic origin (haploid or diploid embryos was checked using a recessive colour (blond and morphological markers. The percentage of hatched embryos in all experimental groups was much lower than in the control groups. All haploid embryos showed morphological abnormalities, which were recorded as haploid syndrome (stunted body, poorly formed retina, etc.. The optimal dose of UV irradiation of common bream and common carp eggs was 3456 J m–2. At this dose, almost 100% of haploid embryos were produced at a hatching rate of over 6%. Lower UV-ray doses affected abnormal embryo development. The highest yield of tench androgenesis (about 2% was noted when eggs were exposed to thermal shock 30 min after egg activation.

  6. Rapid determination of small amount of plutonium in highly radioactive solution for safeguards assay by laser induced photoacoustic spectrometry

    Tokai Reprocessing Plant, Tokai Works is progressing a development of laser induced photoacoustic spectrometry (LIPAS) to determine the plutonium level of the solutions from nuclear fuel for operation management and nuclear material control as well as safeguards. The development of LIPAS is under way as a part of JASPAS, a supporting plan to International Atomic Energy Agency (IAEA). A considerable attention has been paid to LIPAS as a highly sensitive method following the development of highly luminant laser instruments. Pu(6) was chosen as the form to be assayed because Pu(6) was not affected by the presence of other elements in a highly radioactive solution. Since Pu in the solution ordinarily contains Pu(4), Pu determination was carried out after the conversion to Pu(6) by adding an oxidant. Both fundamental and practical investigations with highly radioactive solution by LIPS were presented in this report. (M.N.)

  7. Remote monostatic detection of radioactive material by laser-induced breakdown

    Isaacs, Joshua; Miao, Chenlong; Sprangle, Phillip

    2016-03-01

    This paper analyzes and evaluates a concept for remotely detecting the presence of radioactivity using electromagnetic signatures. The detection concept is based on the use of laser beams and the resulting electromagnetic signatures near the radioactive material. Free electrons, generated from ionizing radiation associated with the radioactive material, cascade down to low energies and attach to molecular oxygen. The resulting ion density depends on the level of radioactivity and can be readily photo-ionized by a low-intensity laser beam. This process provides a controllable source of seed electrons for the further collisional ionization (breakdown) of the air using a high-power, focused, CO2 laser pulse. When the air breakdown process saturates, the ionizing CO2 radiation reflects off the plasma region and can be detected. The time required for this to occur is a function of the level of radioactivity. This monostatic detection arrangement has the advantage that both the photo-ionizing and avalanche laser beams and the detector can be co-located.

  8. Measurement of Natural and Artificial Radioactivity in Soil at Some Selected Thanas around the TRIGA Mark-II Research Reactor at AERE, Savar, Dhaka

    Shawpan C. Sarkar; Idris Ali; Debasish Paul; Mahbubur R. Bhuiyan; Sheikh M. A. Islam

    2011-01-01

    The activity concentration of natural and fallout radionuclides in the soil at some selected Thanas around the TRIGA Mark-II Research Reactor at Atomic Energy Research Establishment (AERE), Savar, Dhaka were measured by using a high purity germanium detector (HPGe). The study revealed that only natural radionuclides were present in the samples and no trace of any artificial radionuclide was found. The average activity concentration of 238U, 232Th ...

  9. Cardiomyopathy induced by artificial cardiac pacing: myth or reality sustained by evidence?

    Andrés Di Leoni Ferrari

    2014-09-01

    Full Text Available Implantable cardiac pacing systems are a safe and effective treatment for symptomatic irreversible bradycardia. Under the proper indications, cardiac pacing might bring significant clinical benefit. Evidences from literature state that the action of the artificial pacing system, mainly when the ventricular lead is located at the apex of the right ventricle, produces negative effects to cardiac structure (remodeling, dilatation and function (dissinchrony. Patients with previously compromised left ventricular function would benefit the least with conventional right ventricle apical pacing, and are exposed to the risk of developing higher incidence of morbidity and mortality for heart failure. However, after almost 6 decades of cardiac pacing, just a reduced portion of patients in general would develop these alterations. In this context, there are not completely clear some issues related to cardiac pacing and the development of this cardiomyopathy. Causality relationships among QRS widening with a left bundle branch block morphology, contractility alterations within the left ventricle, and certain substrates or clinical (previous systolic dysfunction, structural heart disease, time from implant or electrical conditions (QRS duration, percentage of ventricular stimulation are still subjecte of debate. This review analyses contemporary data regarding this new entity, and discusses alternatives of how to use cardiac pacing in this context, emphasizing cardiac resynchronization therapy.

  10. Processes of radiation-induced defect formation in quartz. III. Artificial amethyst

    It is shown that during gamma irradiation of r-crystals of amethyst in the dose range 104-106 R there are processes of migration of electron-alkali ion pairs (e-, Me+) and e-, H+ from O- Me+ and O-H+ groups of structural defects to triply coordinate Si↑ ions near interstitial iron ions. These processes create the necessary conditions for occurrence in the dose range 3 x 105-107 R of processes of countermigration of Me+ and H+ ions. With irradiation of amethyst by doses of over 106 R, the formation of marked concentrations of broken Si-O bonds causes the processes of migration of pairs e-, Me+ from growth defects to these radiation traps. The proposed model of radiation-stimulated processes explains the kinetics of the change in the main parameters of the optical absorption spectra in the UV, visible, and IR regions, acoustic (f = 1 MHz) and dielectric (f = 1 kHz) losses of artificial amethyst under gamma irradiation

  11. Electric effects induced by artificial seismic sources at Somma-Vesuvius volcano

    Rosa Di Maio

    2013-11-01

    Full Text Available In this paper, we present a series of self-potential measurements at Somma-Vesuvius volcanic area acquired in conjunction with an active seismic tomography survey. The aim of our study is both to provide further confirmation to the occurrence of seismo-electric coupling and to identify sites suitable for self-potential signal monitoring at Somma-Vesuvius district. The data, which were collected along two perpendicular dipoles, show significant changes on the natural electric field pattern. These variations, attributable to electrokinetic processes triggered by the artificial seismic waves, were observed after explosions occurred at a distance less than 5 km from the SP dipole arrays. In particular, we found that the NW-SE component of the natural electric field was more sensible to the shots than the NE-SW one, and the major effects did not correspond to the nearest shots. Such evidences were interpreted considering the underground electrical properties as deduced by previous detailed resistivity and self-potential surveys performed in the study area.

  12. A new possible biological interface model useful to narrate the artificial negative events by the radioactive contaminations and heavy-metals pollution of the soil and the atmosphere in different areas of Europe

    A lot of environmental negative effects are associated to the pollution and radioactive contaminations of the soil and the atmosphere. Actually the C.I.S.A.M. (Interforces Centre for Studies and Military Applications) receives increasing commitments to control and to knowledge about the risks of the population and soldiers employed as stabilization or keeping peace force in large areas of different territories of Europe and other sites of the Planet. The aim of this work is focused to compare the contents of radionuclides on specific natural interfaces in different areas as residual radioactive contamination in addition to the other possible heavy-metals pollution. We used barks, lichens and symbiontic microalgae as interfaces with the atmospheric events of the Chernobyl, Balkan, and the Italian areas. The qualitative analysis of these biological matters showed the constant presence of Radiocesium, along with other radionuclides, of which we report the concentrations. Even if these observations are not completely new, nevertheless we can suppose that this approach could be a new possible interface model useful to narrate the sequence of the the artificial negative events due to the human activities and contemporarely an indirect valuation of different risks pointed to the protection of the exposed population

  13. Experimentally induced gluten enteropathy in artificially fed neonatal rats. Protective effect of epidermal growth factor (EGF)

    Štěpánková, Renata; Kofroňová, Olga; Tučková, Ludmila; Kozáková, Hana; Tlaskalová, Helena

    Paříž, 2002. s. 51. [International Symposium On Coeliac Disease /10./. 02.06.2002-05.06.2002, Paříž] R&D Projects: GA ČR GA303/00/1370 Grant ostatní: OLGI1999-000(FR) 50 Keywords : induced gluten * epidermal * growth factor Subject RIV: EE - Microbiology, Virology

  14. A Calculation of the radioactivity induced in PWR cluster control rods with the origin and casmo codes

    The radioactivity induced in PWR cluster control rods during reactor operation has been calculated using the computer programme ORIGEN. Neutron fluxes and spectrum conditions as well as the strongly shielded cross sections for the absorber materials Ag, In and Cd have been obtained by running the cell and assembly code CASMO for a couple of typical cases. The results show that Ag-110m, Fe-55 and Co-60 give the largest activity contributions in the interval 1-10 years after the end of irradiation, and Ni-63 and Cd-113m in a longer time perspective. (author)

  15. An approximate relation for the prediction of the dose rate from radioactivity induced in high energy particle accelerators

    Sullivan, A H

    1972-01-01

    If the dose rate from radioactivity induced by high energy particle radiation depends on irradiation time T and decay time T according to D=K0log (T+t/T), where 0 is the flux density of high-energy particles causing the activation and K is a constant for any given set of irradiation, target and geometrical conditions, then this paper shows that K can be estimated such that the formula can be used to make absolute dose rate predictions of sufficient accuracy for radiation protection purposes.

  16. Investigation of induced radioactivity in different target materials for on-line isotope separator target-source system

    The variation of the induced radioactivity and gamma ray intensity with time for the irradiated target materials of on-line isotope separator target-source system by a proton beam with energy of 100 MeV and intensity 200 μA were calculated by LCS + CBURN code. This work will provide a reference to the design, exchange and disposal of target. The tritium was produced after irradiation by proton beams for all target materials, especially there is 131I in lead target material. (authors)

  17. Reaction dynamics induced by the radioactive ion beam 7Be on medium-mass and heavy targets

    Mazzocco, M.; Boiano, A.; Boiano, C.; La Commara, M.; Manea, C.; Parascandolo, C.; Pierroutsakou, D.; Stefanini, C.; Strano, E.; Torresi, D.; Acosta, L.; Di Meo, P.; Fernandez-Garcia, J. P.; Glodariu, T.; Grebosz, J.; Guglielmetti, A.; Keeley, N.; Lay, J. A.; Marquinez-Duran, G.; Martel, I.; Mazzocchi, C.; Molini, P.; Nicoletto, M.; Pakou, A.; Parkar, V. V.; Rusek, K.; Sánchez-Benítez, A. M.; Sandoli, M.; Sava, T.; Sgouros, O.; Signorini, C.; Silvestri, R.; Soramel, F.; Soukeras, V.; Stiliaris, E.; Stroe, L.; Toniolo, N.; Zerva, K.

    2015-10-01

    We studied the reaction dynamics induced at Coulomb barrier energies by the weakly-bound Radioactive Ion Beam 7Be (Sα = 1.586 MeV) on medium-mass (58Ni) and heavy (208Pb) targets. The experiments were performed at INFN-LNL (Italy), where a 2-3×105 pps 7Be secondary beam was produced with the RIB in-flight facility EXOTIC. Charged reaction products were detected by means of high-granularity silicon detectors in rather wide angular ranges. The contribution presents an up-to-date status of the data analysis and theoretical interpretation for both systems.

  18. Reaction dynamics induced by the radioactive ion beam 7Be on medium-mass and heavy targets

    We studied the reaction dynamics induced at Coulomb barrier energies by the weakly-bound Radioactive Ion Beam 7Be (Sα = 1.586 MeV) on medium-mass (58Ni) and heavy (208Pb) targets. The experiments were performed at INFN-LNL (Italy), where a 2-3×105 pps 7Be secondary beam was produced with the RIB in-flight facility EXOTIC. Charged reaction products were detected by means of high-granularity silicon detectors in rather wide angular ranges. The contribution presents an up-to-date status of the data analysis and theoretical interpretation for both systems

  19. Measurement and analysis of radioactivity induced in steels and a vanadium alloy by 14-MeV neutrons

    Richter, D.; Forrest, R. A.; Freiesleben, H.; Kovalchuk, Va. D.; Kovalchuk D, Vi.; Markovskij, D. V.; Seidel, K.; Tereshkin, V. I.; Unholzer, S.

    2000-12-01

    Samples of the structural material of the International Thermonuclear Experimental Reactor (SS316), of the low-activation steels MANET and F82H, and of the vanadium alloy V4Ti4Cr were irradiated with D-T fusion neutrons. The radioactivities induced were determined after irradiation several times during decay by γ-spectroscopy. The results were analysed with the European Activation System (EASY-97). In order to validate EASY-97, the total activities of the samples are compared, and ratios of calculated-to-experimental values for the individual activities are derived and discussed.

  20. Force induced and electron stimulated STM manipulations: routes to artificial nanostructures as well as to molecular contacts, engines and switches

    Initially invented to image surfaces down to atomic scale, the scanning tunneling microscope (STM) has been further developed in the last few years to an operative tool, with which atoms and molecules can be manipulated at low substrate temperatures at will with atomic precision in different manners by using solely the tip-adparticle forces. In this way various artificial structures on nanoscale have been created and in situ characterized with the STM. Such structures as well as single molecules can be investigated by scanning tunnelling spectroscopy (STS) both with respect to their local electronic and even vibrational properties. Modifications of single molecules can be induced by using the tunnelling electron current: Rotations, diffusional jumps, vibrational excitations, desorption, dissociation and even association can be induced in individual molecules, often in a rather precise way by tuning the voltage into the energy levels of specific vibrations or electronic levels. These possibilities give rise to startling new opportunities for physical and chemical experiments on the single atom and single molecule level. Here a brief overview on results obtained with these new techniques is given

  1. Artificial neural network for Cu quantitative determination in soil using a portable Laser Induced Breakdown Spectroscopy system

    Laser Induced Breakdown Spectroscopy (LIBS) is an advanced analytical technique for elemental determination based on direct measurement of optical emission of excited species on a laser induced plasma. In the realm of elemental analysis, LIBS has great potential to accomplish direct analysis independently of physical sample state (solid, liquid or gas). Presently, LIBS has been easily employed for qualitative analysis, nevertheless, in order to perform quantitative analysis, some effort is still required since calibration represents a difficult issue. Artificial neural network (ANN) is a machine learning paradigm inspired on biological nervous systems. Recently, ANNs have been used in many applications and its classification and prediction capabilities are especially useful for spectral analysis. In this paper an ANN was used as calibration strategy for LIBS, aiming Cu determination in soil samples. Spectra of 59 samples from a heterogenic set of reference soil samples and their respective Cu concentration were used for calibration and validation. Simple linear regression (SLR) and wrapper approach were the two strategies employed to select a set of wavelengths for ANN learning. Cross validation was applied, following ANN training, for verification of prediction accuracy. The ANN showed good efficiency for Cu predictions although the features of portable instrumentation employed. The proposed method presented a limit of detection (LOD) of 2.3 mg dm-3 of Cu and a mean squared error (MSE) of 0.5 for the predictions

  2. Artificially induced hotspots in Bi2Sr2CaCu2O8 mesa terahertz sources

    Hao, Yang; Welp, Ulrich; Koshelev, Alexei; Vlasko-Vlasov, Vitalii; Kwok, Wai-Kwong; Kadowaki, Kazuo; Benseman, Timothy

    Mesa-shaped devices comprising stacked Intrinsic Josephson Junctions (IJJs) in the high-temperature superconductor Bi2Sr2CaCu2O8 can be used as compact sources of coherent terahertz radiation. Achieving high emission levels of THz emission power from these devices depends on efficient synchronization of the approximately 600 IJJs in the stack. Theoretical simulations of stacked IJJs, as well as some empirical results, suggest that thermal inhomogeneity of the stack may enhance THz emission power. There are a number of possible mechanisms by which this might occur, including a hotspot acting as a local resistive shunt for the IJJs (thus altering the spread of bias voltages in the stack and the junction damping dynamics) or by local self-heating reducing the phase-stiffness of the superconducting condensate in critical locations. Here we report results of artificially inducing local heating in these devices with thin film micro-heaters patterned on their surfaces, in order to determine which mechanism(s) could be responsible for self-heating-induced THz emission enhancement. Sample patterning was performed at the Center for Nanoscale Materials, an Office of Science user facility, supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

  3. A Novel Approach for Blast-Induced Flyrock Prediction Based on Imperialist Competitive Algorithm and Artificial Neural Network

    Aminaton Marto

    2014-01-01

    Full Text Available Flyrock is one of the major disturbances induced by blasting which may cause severe damage to nearby structures. This phenomenon has to be precisely predicted and subsequently controlled through the changing in the blast design to minimize potential risk of blasting. The scope of this study is to predict flyrock induced by blasting through a novel approach based on the combination of imperialist competitive algorithm (ICA and artificial neural network (ANN. For this purpose, the parameters of 113 blasting operations were accurately recorded and flyrock distances were measured for each operation. By applying the sensitivity analysis, maximum charge per delay and powder factor were determined as the most influential parameters on flyrock. In the light of this analysis, two new empirical predictors were developed to predict flyrock distance. For a comparison purpose, a predeveloped backpropagation (BP ANN was developed and the results were compared with those of the proposed ICA-ANN model and empirical predictors. The results clearly showed the superiority of the proposed ICA-ANN model in comparison with the proposed BP-ANN model and empirical approaches.

  4. Residual neutron-induced radioactivities of Co-60 and Eu-152 in rocks exposed to Nagasaki Atomic Bomb

    Radioactivities of residual neutron-induced radionuclides of Co-60 and Eu-152 in rocks exposed by Nagasaki Atomic Bomb were determined. Samples were obtained from the surface to 2 cm in depth of rocks. Each sample was pulverized and placed in a plastic container, and gamma-ray spectrum was measured with a pure germanium semiconductor detector. To determine the amount of natural element of cobalt and europium contained in each sample, the neutron activation method was performed by the reactor of the Research Reactor Institute, Kyoto University (KUR). The radioactivities of Co-60 and Eu-152 were evaluated as per 1 mg natural element at the time of Atomic Bomb. The results show that the radioactivities of Co-60 and Eu-152 in rocks were decreased with increasing slant distance. The Co-60 activity was 6.88±2.13 Bq/mgCo and the Eu-152 activity was 75.9±8.79 Bq/mgEu at 510 m from the epicenter. When we compared the activity of Eu-152 calculated by Loewe with our data, we found a divergence between them as the distance from the epicenter increases. (author)

  5. Artificial intelligence

    Hunt, Earl B

    1975-01-01

    Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

  6. Probing the connection of PBSs to the photosystems in Spirulina platensis by artificially induced fluorescence fluctuations

    The molecular architecture and the structural connections of phycobilisomes (PBSs) to the photosystems in the intact cells of Spirulina platensis were studied by taking advantage of glycerol- and betaine-induced fluorescence fluctuations. Generally, with a selective excitation of C-phycocyanin (C-PC), glycerol could induce not only decoupling of PBSs from the photosystems but also of C-PC rods from allophycocyanin (APC) cores, while betaine could strengthen the connection of PBSs to the thylakoid membrane but induce a partial dissociation of PBS. On the other hand, glycerol did not exert an influence on the fluorescence spectra of the photosystems in isolated thylakoid membrane. Therefore, it was deduced that glycerol could provide a molecular environment to weaken the hydrophobic interactions of not only the LCM with the membrane but also the linker polypeptides to the water-soluble phycobiliproteins (C-PC and APC), while the betaine could strengthen the hydrophobic interaction of LCM with the membrane but weaken the electrostatic interaction of linker polypeptides to C-PC and/or APC

  7. Probing the connection of PBSs to the photosystems in Spirulina platensis by artificially induced fluorescence fluctuations

    Li Heng [Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Yang Shuzhen [Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Xie Jie [Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Zhao Jingquan [Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China)]. E-mail: zhaojq@iccas.ac.cn

    2007-01-15

    The molecular architecture and the structural connections of phycobilisomes (PBSs) to the photosystems in the intact cells of Spirulina platensis were studied by taking advantage of glycerol- and betaine-induced fluorescence fluctuations. Generally, with a selective excitation of C-phycocyanin (C-PC), glycerol could induce not only decoupling of PBSs from the photosystems but also of C-PC rods from allophycocyanin (APC) cores, while betaine could strengthen the connection of PBSs to the thylakoid membrane but induce a partial dissociation of PBS. On the other hand, glycerol did not exert an influence on the fluorescence spectra of the photosystems in isolated thylakoid membrane. Therefore, it was deduced that glycerol could provide a molecular environment to weaken the hydrophobic interactions of not only the L{sub CM} with the membrane but also the linker polypeptides to the water-soluble phycobiliproteins (C-PC and APC), while the betaine could strengthen the hydrophobic interaction of L{sub CM} with the membrane but weaken the electrostatic interaction of linker polypeptides to C-PC and/or APC.

  8. RETRACTED ARTICLE: Radiation Sialadenitis Induced by High-dose Radioactive Iodine Therapy

    Jeong, Shin Young; Lee, Jaetae

    2010-01-01

    Radioactive iodine (131I) is accumulated in the thyroid tissue and plays an important role in the treatment of differentiated papillary and follicular cancers after thyroidectomy. Simultaneously, 131I is concentrated in the salivary glands and secreted into the saliva. Dose-related damage to the salivary parenchyma results from the 131I irradiation. Salivary gland swelling and pain, usually involving the parotid, can be seen. The symptoms may develop immediately after a therapeutic dose of 13...

  9. Alloy development for fast induced radioactivity decay for fusion reactor applications

    The Cr-Mo ferritic (martensitic) steels and austenitic stainless steels (primarily type 316 and variations on that composition) are the leading candidates for the structural components for future fusion reactors. However, irradiation of such steels in a fusion environment produces long-lived radioactive isotopes. These isotopes lead to difficult radioactive waste disposal problems once the structure is removed from service. Such problems could be reduced by developing steels that contain only elements that produce radioactive isotopes that decay to low levels in a reasonable time (tens of years instead of hundreds or thousands of years). This report discusses the development of such steels by making elemental substitutions in the steels now under consideration. Molybdenum must be replaced in the Cr-Mo steels; nickel and molybdenum both must be replaced in the austenitic stainless steels (the nitrogen concentration must be limited, and niobium, maintained to extremely low levels). Appropriate substitutions are tungsten for molybdenum in the Cr-Mo steels and manganese for nickel in the austenitic stainless steels. Indications are that suitable ferritic steels can be developed, but development of a nickel-free austenitic stainless steel with properties similar to the Cr-Ni stainless steels appears to be much more complex

  10. Piezomagnetic effects induced by artificial sources at Mt. Vesuvius (Italy: preliminary results of an experimental survey

    R. Napoli

    1998-06-01

    Full Text Available In order to put new constrains on magnetic effects associated with mechanical stresses, high frequency monitoring of the geomagnetic field was carried out during a seismic tomography experiment (TOMOVES'96 project at Mt. Vesuvius. Eight proton precession and one Cesium magnetometers were installed along a profile on the SW flank of the volcano to observe possible magnetic changes induced by explosions. Measurements were performed at different sampling frequencies (10 Hz, 0.5 Hz and 0.1 Hz. A remarkable change in the intensity of the magnetic field was observed in only one case. The magnetic transient lasted 12-13 min, reaching the maximum amplitude of slightly less than 15 nT.

  11. Measurement of induced radioactivities for the evaluation of internal exposure at high energy accelerator facilities

    At high-intense and high energy accelerator facilities, accelerator components are exposed to primary and/or secondary high energy particles during machine operation. As a result, these become radioactive and the radioactivities are accumulated with operation time. When workers engage in maintenance work such as cutting, welding, etc. in the areas with residual activities. These become a source of internal exposure through the inhalation of radioactive airbornes as well as a source of external exposure. The estimation of external doses to workers is relatively easy by directly measuring the radiation fields by pertinent radiation counters. While the internal dose depends very much on the kinds of radioactive nuclides and their concentrations in air. In a routine survey for internal dose evaluation, airborne activities are filtered and their activities on the filter are measured with a GM counter with an automatic sample changer at KEK (the High Energy Accelerator Research Organization). Ordinarily many filter samples have to be measured with a relatively short counting time, so this gross beta counting is a practical way in a routine procedure. In order to evaluate the internal dose from these countings, it is necessary to examine precisely the kinds of radioactivities and their concentrations collected on the filters by a Ge semiconductor detector, and the correlation between the gross beta counting and the actual dose has to be made clear in advance. However, kinds of radioactivities and their concentrations depend very much on production rates of individual nuclides and time variations after beam-off. First, in order to elucidate the production rates of individual nuclides and their concentrations after beam-off, metal samples of Al, Fe, Cu, Steel, etc., which are principal materials used in accelerator facilities, were irradiated at various places in the tunnel of KEK-500MeV and 12GeV proton synchrotrons. By using these irradiated samples, we examined

  12. Assessment of natural and artificial radioactivity levels and radiation hazards and their relation to heavy metals in the industrial area of Port Said city, Egypt.

    Attia, T E; Shendi, E H; Shehata, M A

    2015-02-01

    A detailed gamma ray spectrometry survey was carried out to make an action in environmental impact assessment of urbanization and industrialization on Port Said city, Egypt. The concentrations of the measured radioelements U-238, Th-232 in ppm, and K-40 %, in addition to the total counts of three selected randomly dumping sites (A, B, and C) were mapped. The concentration maps represent a base line for the radioactivity in the study area in order to detect any future radioactive contamination. These concentrations are ranging between 0.2 and 21 ppm for U-238 and 0.01 to 13.4 ppm for Th-232 as well as 0.15 to 3.8 % for K-40, whereas the total count values range from 8.7 to 123.6 uR. Moreover, the dose rate was mapped using the same spectrometer and survey parameters in order to assess the radiological effect of these radioelements. The dose rate values range from 0.12 to 1.61 mSv/year. Eighteen soil samples were collected from the sites with high radioelement concentrations and dose rates to determine the activity concentrations of Ra-226, Th-232, and K-40 using HPGe spectrometer. The activity concentrations of Ra-226, Th-232, and K-40 in the measured samples range from 18.03 to 398.66 Bq kg(-1), 5.28 to 75.7 Bq kg(-1), and 3,237.88 to 583.12 Bq kg(-1), respectively. In addition to analyze heavy metal for two high reading samples (a 1 and a 10) which give concentrations of Cd and Zn elements (a 1 40 ppm and a 10 42 ppm) and (a 1 0.90 ppm and a 10 0.97 ppm), respectively, that are in the range of phosphate fertilizer products that suggested a dumped man-made waste in site A. All indicate that the measured values for the soil samples in the two sites of three falls within the world ranges of soil in areas with normal levels of radioactivity, while site A shows a potential radiological risk for human beings, and it is important to carry out dose assessment program with a specifically detailed monitoring program periodically. PMID:25233912

  13. Morning sector drift-bounce resonance driven ULF waves observed in artificially-induced HF radar backscatter

    L. J. Baddeley

    Full Text Available HF radar backscatter, which has been artificially-induced by a high power RF facility such as the EISCAT heater at Tromsø, has provided coherent radar ionospheric electric field data of unprecedented temporal resolution and accuracy. Here such data are used to investigate ULF wave processes observed by both the CUTLASS HF radars and the EISCAT UHF radar. Data from the SP-UK-OUCH experiment have revealed small-scale (high azimuthal wave number, m -45 waves, predominantly in the morning sector, thought to be brought about by the drift-bounce resonance processes. Conjugate observations from the Polar CAM-MICE instrument indicate the presence of a non-Maxwellian ion distribution function. Further statistical analysis has been undertaken, using the Polar TIMAS instrument, to reveal the prevalence and magnitude of the non-Maxwellian energetic particle populations thought to be responsible for generating these wave types.

    Key words. Ionosphere (active experiments; wave-particle interactions Magnetospheric physics (MHD waves and instabilities

  14. The Influence of Acute Hyperglycemia in an Animal Model of Lacunar Stroke That Is Induced by Artificial Particle Embolization

    Tsai, Ming-Jun; Lin, Ming-Wei; Huang, Yaw-Bin; Kuo, Yu-Min; Tsai, Yi-Hung

    2016-01-01

    Animal and clinical studies have revealed that hyperglycemia during ischemic stroke increases the stroke's severity and the infarct size in clinical and animal studies. However, no conclusive evidence demonstrates that acute hyperglycemia worsens post-stroke outcomes and increases infarct size in lacunar stroke. In this study, we developed a rat model of lacunar stroke that was induced via the injection of artificial embolic particles during full consciousness. We then used this model to compare the acute influence of hyperglycemia in lacunar stroke and diffuse infarction, by evaluating neurologic behavior and the rate, size, and location of the infarction. The time course of the neurologic deficits was clearly recorded from immediately after induction to 24 h post-stroke in both types of stroke. We found that acute hyperglycemia aggravated the neurologic deficit in diffuse infarction at 24 h after stroke, and also aggravated the cerebral infarct. Furthermore, the infarct volumes of the basal ganglion, thalamus, hippocampus, and cerebellum but not the cortex were positively correlated with serum glucose levels. In contrast, acute hyperglycemia reduced the infarct volume and neurologic symptoms in lacunar stroke within 4 min after stroke induction, and this effect persisted for up to 24 h post-stroke. In conclusion, acute hyperglycemia aggravated the neurologic outcomes in diffuse infarction, although it significantly reduced the size of the cerebral infarct and improved the neurologic deficits in lacunar stroke.

  15. Artificially induced epithelial-mesenchymal transition in surgical subjects: its implications in clinical and basic cancer research.

    Kazuhiko Aoyagi

    Full Text Available BACKGROUND: Surgical samples have long been used as important subjects for cancer research. In accordance with an increase of neoadjuvant therapy, biopsy samples have recently become imperative for cancer transcriptome. On the other hand, both biopsy and surgical samples are available for expression profiling for predicting clinical outcome by adjuvant therapy; however, it is still unclear whether surgical sample expression profiles are useful for prediction via biopsy samples, because little has been done about comparative gene expression profiling between the two kinds of samples. METHODOLOGY AND FINDINGS: A total of 166 samples (77 biopsy and 89 surgical of normal and malignant lesions of the esophagus were analyzed by microarrays. Gene expression profiles were compared between biopsy and surgical samples. Artificially induced epithelial-mesenchymal transition (aiEMT was found in the surgical samples, and also occurred in mouse esophageal epithelial cell layers under an ischemic condition. Identification of clinically significant subgroups was thought to be disrupted by the disorder of the expression profile through this aiEMT. CONCLUSION AND SIGNIFICANCE: This study will evoke the fundamental misinterpretation including underestimation of the prognostic evaluation power of markers by overestimation of EMT IN past cancer research, and will furnish some advice for the near future as follows: 1 Understanding how long the tissues were under an ischemic condition. 2 Prevalence of biopsy samples for in vivo expression profiling with low biases on basic and clinical research. 3 Checking cancer cell contents and normal- or necrotic-tissue contamination in biopsy samples for prevalence.

  16. Ambient radioactivity levels and radiation doses. Annual report 2012

    The annual report 2012 on ambient radioactivity levels and radiation doses covers the following issues: Part A: General information: natural environmental radioactivity; artificial radioactivity in the environment; occupational radiation exposure; radiation exposures from medical applications; the handling of radioactive materials and sources of ionizing radiation; non-ionizing radiation. Part B: Current data and their evaluation: natural environmental radioactivity; artificial radioactivity in the environment; occupational radiation exposures; radiation exposures from medical applications; the handling of radioactive materials and sources of ionizing radiation; non-ionizing radiation. The report includes data on the stock of radioactive waste, radiation accidents and unusual events.

  17. Double pulse laser induced breakdown spectroscopy applied to natural and artificial materials from cultural heritages

    The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown in recent years its great potential for rapid qualitative analysis of materials. Thanks to the possibility to implement a portable instrument that perform LIBS analysis, this technique is revealed to be particularly useful for in situ analysis in the field of cultural heritages. The purpose of this work is to evaluate the potentiality of LIBS technique in the field of cultural heritages, with respect to the chemical characterization of complex matrix as calcareous and refractory materials for further quantitative analyses on cultural heritages. X-Ray Fluorescence (XRF) analyses were used as reference. Calibration curves of certified materials used as standards were obtained by XRF analyses. The LIBS measurements were performed with a new mobile instrument called Modi (Mobile Double pulse Instrument for LIBS Analysis). The XRF analyses were performed with a portable instrument ArtTAX. LIBS and XRF measurement were performed on both reference materials and samples (bricks and mortars) sampled in the ancient Greek-Roman Theatre of Taormina. Although LIBS measurements performed on reference materials have shown non linear response to concentrations, and so we were not able to obtain quantitative results, an integrated study of XRF and LIBS signals permitted us to distinguish among chemical features and degradation state of measured building materials.

  18. Three-dimentional simulation of flow-induced platelet activation in artificial heart valves

    Hedayat, Mohammadali; Asgharzadeh, Hafez; Borazjani, Iman

    2015-11-01

    Since the advent of heart valve, several valve types such as mechanical and bio-prosthetic valves have been designed. Mechanical Heart Valves (MHV) are durable but suffer from thromboembolic complications that caused by shear-induced platelet activation near the valve region. Bio-prosthetic Heart Valves (BHV) are known for better hemodynamics. However, they usually have a short average life time. Realistic simulations of heart valves in combination with platelet activation models can lead to a better understanding of the potential risk of thrombus formation in such devices. In this study, an Eulerian approach is developed to calculate the platelet activation in three-dimensional simulations of flow through MHV and BHV using a parallel overset-curvilinear immersed boundary technique. A curvilinear body-fitted grid is used for the flow simulation through the anatomic aorta, while the sharp-interface immersed boundary method is used for simulation of the Left Ventricle (LV) with prescribed motion. In addition, dynamics of valves were calculated numerically using under-relaxed strong-coupling algorithm. Finally, the platelet activation results for BMV and MHV are compared with each other.

  19. Double pulse laser induced breakdown spectroscopy applied to natural and artificial materials from cultural heritages

    Brai, Maria; Gennaro, Gaetano [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze Ed.18, 90128 Palermo (Italy); Schillaci, Tiziano, E-mail: tschillaci@unipa.i [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze Ed.18, 90128 Palermo (Italy); Tranchina, Luigi [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze Ed.18, 90128 Palermo (Italy)

    2009-10-15

    The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown in recent years its great potential for rapid qualitative analysis of materials. Thanks to the possibility to implement a portable instrument that perform LIBS analysis, this technique is revealed to be particularly useful for in situ analysis in the field of cultural heritages. The purpose of this work is to evaluate the potentiality of LIBS technique in the field of cultural heritages, with respect to the chemical characterization of complex matrix as calcareous and refractory materials for further quantitative analyses on cultural heritages. X-Ray Fluorescence (XRF) analyses were used as reference. Calibration curves of certified materials used as standards were obtained by XRF analyses. The LIBS measurements were performed with a new mobile instrument called Modi (Mobile Double pulse Instrument for LIBS Analysis). The XRF analyses were performed with a portable instrument ArtTAX. LIBS and XRF measurement were performed on both reference materials and samples (bricks and mortars) sampled in the ancient Greek-Roman Theatre of Taormina. Although LIBS measurements performed on reference materials have shown non linear response to concentrations, and so we were not able to obtain quantitative results, an integrated study of XRF and LIBS signals permitted us to distinguish among chemical features and degradation state of measured building materials.

  20. Artificial Limbs

    ... you are missing an arm or leg, an artificial limb can sometimes replace it. The device, which ... activities such as walking, eating, or dressing. Some artificial limbs let you function nearly as well as ...

  1. Response of native flora to inducible genotoxic damage from increased radioactivity around NPP Jaslovske Bohunice, Slovakia

    It is not generally known that the first serious failure of nuclear power plant (NPP) technology with loss of human lives occurred in NPP Jaslovske Bohunice (Czechoslovakia) in January 1976. A year later the second accident finally broken reactor A1 with large radioactive contamination. This material was later (in 1980) washed into the nearby drainage by the heavy rain. In cleaning procedure, the contaminated soil particles contaminated the slopes of the drainage. These spots have the shape of 'blurs' about 15 cm wide with a scale of contamination from 0,067; 0,15; 2,38; 9,5; 45.5 up to 322 kBq/kg 137Cs. The research was done in cooperation with the Institute of Tumorbiology, University of Vienna, within the grant Action Austria - Slovak Republic. Details of radioactivity at the area were obtained thanks to the Research Institute of the Nuclear Energy in Trnava, Slovakia. In our ten years long-term study of contaminated soil around nuclear power plant (NPP) Jaslovske Bohunice 24 species of local flora were used to show impact of these accidents. The 19 km long banks of the Jaslovske Bohunice NPP waste water recipient has been identified as contaminated by 137Cs. In total, more than 67,000 m2 of river banks have been found as being contaminated at levels exceeding 1 Bq 137Cs/g of soil. Used phytotoxic and cytogenetic -in situ' tests were extended by analyses of pollen grains. Although the dose of some samples of radioactive soil was relatively high (322 kBq kg-1) no any significant impact on the biological level of tested wild plant species was observed. Possible explanation (such as adaptation and resistance) is discussed. (author)

  2. Neutron yield and induced radioactivity: a study of 235-MeV proton and 3-GeV electron accelerators

    This study evaluated the magnitude of potential neutron yield and induced radioactivity of two new accelerators in Taiwan: a 235-MeV proton cyclotron for radiation therapy and a 3-GeV electron synchrotron serving as the injector for the Taiwan Photon Source. From a nuclear interaction point of view, neutron production from targets bombarded with high-energy particles is intrinsically related to the resulting target activation. Two multi-particle interaction and transport codes, FLUKA and MCNPX, were used in this study. To ensure prediction quality, much effort was devoted to the associated benchmark calculations. Comparisons of the accelerators' results for three target materials (copper, stainless steel and tissue) are presented. Although the proton-induced neutron yields were higher than those induced by electrons, the maximal neutron production rates of both accelerators were comparable according to their respective beam outputs during typical operation. Activation products in the targets of the two accelerators were unexpectedly similar because the primary reaction channels for proton- and electron-induced activation are (p,pn) and (γ,n), respectively. The resulting residual activities and remnant dose rates as a function of time were examined and discussed. (authors)

  3. Reaction dynamics induced by the radioactive ion beam {sup 7}Be on medium-mass and heavy targets

    Mazzocco, M., E-mail: marco.mazzocco@pd.infn.it; Stefanini, C.; Strano, E.; Torresi, D.; Lay, J. A.; Molini, P.; Soramel, F. [Dipartimento di Fisica e Astronomia, Università di Padova, via F. Marzolo 8, I-35131 Padova (Italy); INFN-Sezione di Padova, via F. Marzolo 8, I-35131 Padova (Italy); Boiano, A.; Parascandolo, C.; Pierroutsakou, D.; Di Meo, P. [INFN-Sezione di Napoli, via Cintia, I-80126, Napoli (Italy); Boiano, C. [INFN-Sezione di Milano, via Celoria 16, I-20133, Napoli (Italy); La Commara, M.; Sandoli, M.; Silvestri, R. [INFN-Sezione di Napoli, via Cintia, I-80126, Napoli (Italy); Dipartimento di Fisica, Università di Napoli “Federico II”, via Cintia, I-80126, Napoli (Italy); Manea, C.; Nicoletto, M. [INFN-Sezione di Padova, via F. Marzolo 8, I-35131 Padova (Italy); Acosta, L. [Departamento de Fìsica Aplicada, Universidad de Huelva, Campus de El Carmen, E-21071 Huelva (Spain); INFN-Sezione di Catania, via Santa Sofia 64, I-95123, Catania (Italy); Fernandez-Garcia, J. P. [INFN-Sezione di Catania, via Santa Sofia 64, I-95123, Catania (Italy); Glodariu, T. [National Institute for Physics and Nuclear Engineering (NIPNE), 30 Reactorului St., 077125 Magurele (Romania); and others

    2015-10-15

    We studied the reaction dynamics induced at Coulomb barrier energies by the weakly-bound Radioactive Ion Beam {sup 7}Be (S{sub α} = 1.586 MeV) on medium-mass ({sup 58}Ni) and heavy ({sup 208}Pb) targets. The experiments were performed at INFN-LNL (Italy), where a 2-3×10{sup 5} pps {sup 7}Be secondary beam was produced with the RIB in-flight facility EXOTIC. Charged reaction products were detected by means of high-granularity silicon detectors in rather wide angular ranges. The contribution presents an up-to-date status of the data analysis and theoretical interpretation for both systems.

  4. Radioactive waste disposal in granite

    Within the framework of completing its knowledge of various rock formations, the Federal Government also considers the suitability of granite for radioactive waste disposal. For this purpose, the Federal Minister of Research and Technology participated from 1983 to 1990 in relevant research and development activities in the NAGRA rock laboratory at Grimsel, Switzerland. After about 17 field tests, it can be stated that the understanding of basic connections and interactions between the mechanical behaviour of the rock, which is determined, for instance, by natural or artificially induced rock movements, and the hydrogeological or rock hydraulic relations could be clearly improved. So far, the German share in the project costs amounts to a total of approximately DM 20.7 million. Till the end of 1993, further activities are scheduled to be carried out which will require financial funds of about DM 6.3 million. (orig./HSCH)

  5. Tide induced mathematical model for coastal radioactive discharges and its application

    A mathematical model has been developed to evaluate spatial and temporal distribution of radionuclide concentration from a continous discharge of radioactive liquid effluents into the Tarapur coastal waters, taking into consideration tidal effects and seasonal variation of ocean currents. It is found that all the nuclides studied except 131I, attain steady state concentration more or less at the same time interval after continuous discharge, depending on the distance along the coast. Further, the confinement of radionuclides parallel to the coast is significant. Limiting discharge rates (LDR) for some typical radionuclides have also been computed using a radiological model. The calculations show the the LDR values vary from 7 to 50,000 Ci.d-1, the lowest and highest being for 239Pu and 134Cs respectively. (author)

  6. Induced radioactivity in the target station and decay tunnel from a 4MW proton beam

    Agosteo, S; Otto, T; Silari, Marco

    2003-01-01

    An important aspect of a future CERN Neutrino Factory is the material activation arising from a 2.2 GeV, 4 MW proton beam striking a mercury target. A first estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump has been performed by the Monte Carlo hadronic cascade code FLUKA. The aim is both to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which will have to be disposed of after the facility has ceased operation. This paper discusses the first results of such calculations.

  7. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966); Etude de la radioactivite artificielle du milieu marin par spectrometrie gamma (1962-1966)

    Chesselet, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [French] Les resultats decrits dans cette etude concernent la radioactivite artificielle sous forme de zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 et praseodyme-144 apportee par la retombee

  8. Induced Radioactivity Measured in a Germanium Detector After a Long Duration Balloon Flight

    Starr, R.; Evans, L. G.; Floyed, S. R.; Drake, D. M.; Feldman, W. C.; Squyres, S. W.; Rester, A. C.

    1997-01-01

    A 13-day long duration balloon flight carrying a germanium detector was flown from Williams Field, Antartica in December 1992. After recovery of the payload the activity induced in the detector was measured.

  9. Prospective study in the management of high-dose radioactive iodine therapy induced gastritis

    Full text: Gastritis is simply defined as inflammation of the gastric mucosa. In post-RAI patients, this is one of the most common complications that are encountered. Some patients may even require repetitive administration of high doses of radioactive iodine (I-131). Small doses of radiation (up to 1500 R) cause reversible mucosal damage, whereas higher radiation doses cause irreversible damage with atrophy and ischemic-related ulceration. Reversible changes consist of degenerative changes in epithelial cells and nonspecific chronic inflammatory infiltrate in the lamina propria. Higher amounts of radiation cause permanent mucosal damage, with atrophy of fundic glands, mucosal erosions, and capillary hemorrhage. Associated submucosal endarteritis results in mucosal ischemia and secondary ulcer development. Recurrent gastritis, if left untreated, may be a predisposing factor for gastric malignancy. Methods:A total of thirty post-RAI subjects were evaluated for signs and symptoms of gastritis and were divided into 3 groups which were given drugs for gastritis (H2-receptor antagonist, proton pump inhibitor, and sucralfate). Survey forms were distributed to evaluate the presence of nausea, vomiting, epigastric pain (graded according to severity of pain), and gastrointestinal bleeding. Results were tallied accordingly. Results and Discussion: In a total of 3 subjects who were given sucralfate, all of them did not experience any nausea and vomiting. One subject experienced mild epigastric discomfort and another subject was able to experience a non-specific symptom of abdominal bloatedness. (Note: Subjects are still for completion) In theory, radiation irritates the mucosa causing inflammation and mucosal damage which is further irritated by gastric acid secretion. The administration of H2-receptor blockers and proton pump inhibitors only inhibit gastric acid secretion while existing inflammation of mucosa due to high doses of radiation is left untreated. However

  10. Induced radioactivity and the field of activation products γ-radiation in shielding on investigative reactor IRI-MIFI in problem of decommissioning

    Problem solution peculiarities for forecasting induced radioactivity and characteristics of activation product γ radiation field in single calculation of the primary and secondary particle transport are considered proceeding from the notion of the activation radiation as the secondary delayed radiation in contrast to the secondary instantaneous captured radiation. Calculation program complex is illustrated by induced activation forecasting problem and 60Co γ-radiation maximum equivalent dose rate in shield of the IRI-MIFI research reactor

  11. Induced polarisation and the assessment of sorption/diffusion at radioactive waste repository sites

    Induced polarisation is a geophysical technique used in mineral exploration in search of metallic ore deposits. Clay minerals also polarise when subjected to an electric current, although the mechanism differs from that of metallic bodies, and involves, amongst other properties, the clay mineral species, the interlayer spacing of the clay, and the nature and abundance of mobile ions in the pore fluid. As a result, it was proposed that induced polarisation of clays could be used as a method for determining their permeability and diffusivity. The work carried out in developing experimental procedures, and evaluating the feasibility of the proposal is presented in this report. (author)

  12. Numerical Simulation and Artificial Neural Network Modeling for Predicting Welding-Induced Distortion in Butt-Welded 304L Stainless Steel Plates

    Narayanareddy, V. V.; Chandrasekhar, N.; Vasudevan, M.; Muthukumaran, S.; Vasantharaja, P.

    2016-02-01

    In the present study, artificial neural network modeling has been employed for predicting welding-induced angular distortions in autogenous butt-welded 304L stainless steel plates. The input data for the neural network have been obtained from a series of three-dimensional finite element simulations of TIG welding for a wide range of plate dimensions. Thermo-elasto-plastic analysis was carried out for 304L stainless steel plates during autogenous TIG welding employing double ellipsoidal heat source. The simulated thermal cycles were validated by measuring thermal cycles using thermocouples at predetermined positions, and the simulated distortion values were validated by measuring distortion using vertical height gauge for three cases. There was a good agreement between the model predictions and the measured values. Then, a multilayer feed-forward back propagation neural network has been developed using the numerically simulated data. Artificial neural network model developed in the present study predicted the angular distortion accurately.

  13. Validation of induced radioactivity calculations for candidate fusion materials through measurements in a graphite-centered assembly

    Induced radioactivity measurements were carried out jointly by the USA and Japan in a graphite-centered assembly, in the framework of ITER Task T-218 entitled 'Shielding Blanket Neutronics Experiments'. An intense, accelerator-based D-T rotating target neutron source JAERI, with a nominal intensity of 5 x 1012 s-1, was used. Two locations, providing different neutron energy spectra, were chosen for irradiating samples of a range of materials of interest to ITER. Three independent experimental campaigns were conducted so as to accommodate a large number of samples, on one hand, and as many short and long half-life products as possible, on the other. The total neutron fluence ranged from 4.7 x 1011 to 1.5 x 1014 n cm-2. Altogether, samples of Mg, Al, SiO2, Ti, V, Cr, Mn, Fe, Co, Ni, FH82 steel, SS316LN steel (ITER grade), Cu, Zn, KCl, Zr, Nb, Mo, Ag, ln, Sn, Dy, Ta, Hf, Re, Au, Ir, and Pb were irradiated. The irradiated samples were cooled for variable periods ranging from 30 s to 250 days before their decay gamma-ray spectra were counted on high purity intrinsic germanium detectors. The half lives of the observed radioisotopes have ranged from 18.7 s (46mSc from Ti) to 5.3 years (60Co from Ni). The neutron energy spectra for the two locations were calculated using Monte Carlo code MCNP with FENDL-1 and ENDF/B-VI data libraries. The analysis of isotopic activities, expressed in Bq cc-1, of the irradiated materials has been carried out using REAC-3 radioactivity code, with FENDL-2A and FENDL-1A activation cross-section and decay data libraries. Typically, C/E lies in a band of 0.5-1.5 for the results being reported. (orig.)

  14. Theoretical evaluation of induced radioactivity in food products by electron or X-ray beam sterilization

    We evaluate first the energy density for electrons or X-ray beams necessary to produce a reference level of 1 kilogray at the maximum of dose, as a function of energy, for electrons and bremsstrahlung photons, based on experimental data obtained on radio-therapy beams, from 4 to 32 MeV, and irradiation beams from production plant CARIC. Then from the production of neutrons on the tungsten target and from (γn) reactions on the deuterium content of the irradiated food, the slowing down and capture of these neutrons is estimated. Radioisotopes can be produced by (γn) reactions on iodine, and to a lesser extent on tin, lead, barium, etc., but the major contribution is neutron activation, where the more critical elements are sodium, chlorine, potassium, magnesium, phosphorus, calcium. Induced activity is compared to natural activity coming from potassium 40, carbon 14 and radium, contained in all foods. For electrons up to 1 Mrad the induced activity remains of the order of a few percent of natural activity, for energies below 10 to 11 MeV. Bremsstrahlung X-ray irradiations can give comparable levels as soon as the energy of the generating electron beam is above 3 MeV. The induced activity decays within a few days. (author)

  15. Artificial blood

    Sarkar Suman

    2008-01-01

    Full Text Available Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  16. Induced radioactivity of materials by stray radiation fields at an electron accelerator

    Rokni, S H; Gwise, T; Liu, J C; Roesler, S

    2002-01-01

    Samples of soil, water, aluminum, copper and iron were irradiated in the stray radiation field generated by the interaction of a 28.5 GeV electron beam in a copper-dump in the Beam Dump East facility at the Stanford Linear Accelerator Center. The specific activity induced in the samples was measured by gamma spectroscopy and other techniques. In addition, the isotope production in the samples was calculated with detailed Monte Carlo simulations using the FLUKA code. The calculated activities are compared to the experimental values and differences are discussed.

  17. An active artificial cornea with the function of inducing new corneal tissue generation in vivo-a new approach to corneal tissue engineering

    An active artificial cornea which can perform the function of inducing new cornea generation in vivo but does not need culture cells in vitro and which has similar optical and mechanical properties to those of the human cornea was constructed. An animal keratoplasty experiment using the artificial cornea as the implant showed that the animals' corneas could keep smooth surface and clear stroma postoperatively, and that the repopulation of the host's keratocytes, the degradation of the implant and new corneal tissue generation were completed at 5-6 months after surgery. Such an artificial cornea has several advantages over other corneal equivalents constructed in the typical way of tissue engineering: in having similar mechanical and optical properties to those of the human cornea and with no exogenetic cells, it can be used universally in different implantation surgeries without immunoreaction; it is easy to prepare and process into different shapes and sizes on a large scale, and suitable for long-distance transportation and long-term storage. All these characteristics make it a new approach to cornea tissue engineering having potential in many clinical applications

  18. Induced radioactivity of a GSO scintillator by secondary fragments in carbon ion therapy and its effects on in-beam OpenPET imaging

    Hirano, Yoshiyuki; Nitta, Munetaka; Nishikido, Fumihiko; Yoshida, Eiji; Inadama, Naoko; Yamaya, Taiga

    2016-07-01

    The accumulation of induced radioactivity within in-beam PET scanner scintillators is of concern for its long-term clinical usage in particle therapy. To estimate the effects on OpenPET which we are developing for in-beam PET based on GSOZ (Zi doped Gd2SiO5), we measured the induced radioactivity of GSO activated by secondary fragments in a water phantom irradiation by a 12C beam with an energy of 290 MeV u‑1. Radioisotopes of Na, Ce, Eu, Gd, Nd, Pm and Tb including positron emitters were observed in the gamma ray spectra of the activated GSO with a high purity Ge detector and their absolute radioactivities were calculated. We used the Monte Carlo simulation platform, Geant4 in which the observed radioactivity was assigned to the scintillators of a precisely reproduced OpenPET and the single and coincidence rates immediately after one treatment and after one-year usage were estimated for the most severe conditions. Comparing the highest coincidence rate originating from the activated scintillators (background) and the expected coincidence rate from an imaging object (signal), we determined the expected signal-to-noise ratio to be more than 7 within 3 min and more than 10 within 1 min from the scan start time. We concluded the effects of scintillator activation and their accumulation on the OpenPET imaging were small and clinical long-term usage of the OpenPET was feasible.

  19. Artificial intelligence

    Ennals, J R

    1987-01-01

    Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

  20. Artificial urushi.

    Kobayashi, S; Uyama, H; Ikeda, R

    2001-11-19

    A new concept for the design and laccase-catalyzed preparation of "artificial urushi" from new urushiol analogues is described. The curing proceeded under mild reaction conditions to produce the very hard cross-linked film (artificial urushi) with a high gloss surface. A new cross-linkable polyphenol was synthesized by oxidative polymerization of cardanol, a phenol derivative from cashew-nut-shell liquid, by enzyme-related catalysts. The polyphenol was readily cured to produce the film (also artificial urushi) showing excellent dynamic viscoelasticity. PMID:11763444

  1. Changes of decay rates of radioactive 111In and 32P induced by mechanic motion

    2007-01-01

    The changes of decay rates of radionuclide 111In(electron capture) and 32P(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2000 r/min) ,the half life of 111In compared with the referred(2.83 d) is decreased at 2.83% and increased at 1.77%,respectively;the half life of 32P compared with the referred(14.29 d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.31% and increased at 6.36%,respectively;the half life of 32P is decreased at 10.08% and increased at 4.34%,respectively. When the circular rotation is removed,the decay rates of 111In and 32P return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 32P,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

  2. Artificial Reefs

    National Oceanic and Atmospheric Administration, Department of Commerce — An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block...

  3. Natural - synthetic - artificial!

    Nielsen, Peter E

    2010-01-01

    The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

  4. Artificial radioactive tracers: a tool for oceanography

    In marine hydrodynamic, use of 125Sb as tracer and a two stages coprecipitation analysis process allows to study water motion in the Channel and in the seas of the north east of Europe from effluents of La Hague (France) reprocessing plant. Other tracers may be used: 137Cs coming principally from Sellafield (United Kingdom), and 134Cs coming from Chernobyl accident. (A.B.). 15 refs., 8 figs., 5 tabs

  5. Regional blood flow distribution in dog during induced hypotension and low cardiac output. Spontaneous breathing versus artificial ventilation.

    Viires, N; Sillye, G; Aubier, M.; Rassidakis, A; Roussos, C

    1983-01-01

    Respiratory muscle blood flow and organ blood flow was studied in two groups of dogs with radioactively labeled microspheres to assess the influence of the working respiratory muscles on the regional distribution of blood flow when arterial pressure and cardiac output were lowered by pericardial tamponade. In one group (n = 6), the dogs were paralyzed and mechanically ventilated (Mv), while in the other (n = 6), they were left to breathe spontaneously (Sb). Cardiac output fell to 30% of contr...

  6. Use of artificial tracers in hydrology

    The IAEA has convened an Advisory Group Meeting with the following objectives: To define the role of artificial radioactive tracers for water tracing in comparison with other non-radioactive tracers. To evaluate the real needs of artificial radioactive tracers in hydrology. To identify the fields for which artificial radioactive tracers are useful as well as those in which they can be substituted by other tracers. To discuss the strategy to be adopted to overcome the difficulties derived from the restrictions on the use of radioactive tracers in hydrology. The meeting was held at IAEA Headquarters from 19 to 22 March 1990, and was attended by 30 participants from 15 Member States. The conclusions and recommendations are that the use of artificial radioactive tracers should be restricted to cases where other tracers cannot be used or do not provide the same quality of information. Tritium, iodine-131, bromine-82, chromium-51 in the form of Cr-EDTA, technetium-99m obtained from 99Mo-generators and gold-198 as an adsorbable tracer are, practically, the only radionuclides used for water tracing. The use of other radionuclides for this purpose does not appear to be necessary, possible and/or convenient. Refs, figs and tabs

  7. Radioactive contamination of the environment

    The present work opens a series of publications on the results of long-term observations of environmental radioactive contamination in the environs of Leningrad. In the first issue the technique for determination and the results of observations of surface contamination due to artificial radioactive aerosols are presented for 1959-1977. It is shown that the main source of ground air contamination in Leningrad is the global of fission products resulting from nuclear explosions in the atmosphere. The results presented in this work can be used for estimation of levels and isotope composition of radioactive contamination in the temperature zone of the northern hemisphere

  8. Environmental radioactivity in the antarctic station

    Study about environmental radioactivity in the Peruvian antarctic station Machu Pichu they were carried out during the last three periods to the southern summer. The objective of the project it is to evaluate environmental component in order to elaborate a study it base on the levels background radioactivity and artificial in the antarctic region

  9. Decontamination of radioactive cesium in soil

    Agricultural soil containing radioactive cesium was decontaminated using an extraction method involving aqueous potassium solutions. Results demonstrated that the potassium solution could extract radioactive cesium from soil artificially contaminated with 137Cs, although extraction rate decreased as time after contamination increased. However, visual examination of radioactivity distribution in soil samples significantly contaminated by the accident at the Fukushima Daiichi nuclear power plant showed that radioactive cesium also existed as insoluble particles. Therefore, reducing the volume of radioactive wastes generated from soil decontamination requires a physical decontamination method combined with chemical treatment. (author)

  10. Artificial noses.

    Stitzel, Shannon E; Aernecke, Matthew J; Walt, David R

    2011-08-15

    The mammalian olfactory system is able to detect many more odorants than the number of receptors it has by utilizing cross-reactive odorant receptors that generate unique response patterns for each odorant. Mimicking the mammalian system, artificial noses combine cross-reactive sensor arrays with pattern recognition algorithms to create robust odor-discrimination systems. The first artificial nose reported in 1982 utilized a tin-oxide sensor array. Since then, however, a wide range of sensor technologies have been developed and commercialized. This review highlights the most commonly employed sensor types in artificial noses: electrical, gravimetric, and optical sensors. The applications of nose systems are also reviewed, covering areas such as food and beverage quality control, chemical warfare agent detection, and medical diagnostics. A brief discussion of future trends for the technology is also provided. PMID:21417721

  11. Artificial intelligence

    A vivid example of the growing need for frontier physics experiments to make use of frontier technology is in the field of artificial intelligence and related themes. This was reflected in the second international workshop on 'Software Engineering, Artificial Intelligence and Expert Systems in High Energy and Nuclear Physics' which took place from 13-18 January at France Telecom's Agelonde site at La Londe des Maures, Provence. It was the second in a series, the first having been held at Lyon in 1990

  12. Artificial Intelligence

    Warwick, Kevin

    2011-01-01

    if AI is outside your field, or you know something of the subject and would like to know more then Artificial Intelligence: The Basics is a brilliant primer.' - Nick Smith, Engineering and Technology Magazine November 2011 Artificial Intelligence: The Basics is a concise and cutting-edge introduction to the fast moving world of AI. The author Kevin Warwick, a pioneer in the field, examines issues of what it means to be man or machine and looks at advances in robotics which have blurred the boundaries. Topics covered include: how intelligence can be defined whether machines can 'think' sensory

  13. Experimental studies on the neutron emission spectrum and induced radioactivity of the sup 7 Li(d,n) reaction in the 20-40 MeV region

    Baba, M; Hagiwara, M; Sugimoto, M; Miura, T; Kawata, N; Yamadera, A; Orihara, H

    2002-01-01

    To improve the data accuracy of the neutron emission spectrum of the sup 7 Li(d,n) reaction and the radioactivity ( sup 7 Be, sup 3 H, etc.) accumulated in the sup 7 Li target in IFMIF, we have measured the neutron emission spectrum and the radioactivity of sup 7 Be induced in the lithium target for 25 MeV deuterons at the Tohoku University AVF cyclotron (K=110) facility. Neutron spectra were measured with the time-of-flight (TOF) method at four laboratory angles by using a beam swinger system and a well collimated TOF channel. Induced radioactivity was measured by detecting the gamma-rays from sup 7 Be with a pure Ge detector. Experimental results are compared with other experimental data. The present result of neutron emission spectra are in qualitative agreement with other experimental data but that of sup 7 Be production was much larger than expected by the recent codes. Measurement will be extended to several incident energies up to 40 MeV.

  14. Artificial sweeteners

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie-containin...

  15. Artificial photosynthesis

    Andrew C. Benniston; Anthony Harriman

    2008-01-01

    We raise here a series of critical issues regarding artificial photosynthesis with the intention of increasing awareness about what needs to be done to bring about a working prototype. Factors under consideration include energy and electron transfers, coupled redox reactions, repair mechanisms, and integrated photosystems.

  16. Osmosis-induced water uptake by Eurobitum bituminized radioactive waste and pressure development in constant volume conditions

    Marieen, A., E-mail: amarien@sckcen.be [Waste and Disposal Expert Group, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol (Belgium); Mokni, N., E-mail: Nadia.mokni@upc.edu [Department of Geotechnical Engineering and Geosciences, Universidad Politecnica de Catalunya (UPC), Calle Gran Capitan, s/n, Edificio C-1, 08034 Barcelona (Spain); Valcke, E. [Waste and Disposal Expert Group, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol (Belgium); Olivella, S. [Department of Geotechnical Engineering and Geosciences, Universidad Politecnica de Catalunya (UPC), Calle Gran Capitan, s/n, Edificio C-1, 08034 Barcelona (Spain); Smets, S. [Waste and Disposal Expert Group, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol (Belgium); Li, X., E-mail: xli@sckcen.be [EIG EURIDICE, Boeretang 200, 2400 Mol (Belgium)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer The water uptake by Eurobitum is studied to judge the safety of geological disposal. Black-Right-Pointing-Pointer High pressures of up to 20 MPa are measured in constant volume water uptake tests. Black-Right-Pointing-Pointer The morphology of leached Eurobitum samples is studied with {mu}CT and ESEM. Black-Right-Pointing-Pointer The observations are reproduced by an existing CHM formulation for Eurobitum. - Abstract: The chemo-hydro-mechanical (CHM) interaction between swelling Eurobitum radioactive bituminized waste (BW) and Boom Clay is investigated to assess the feasibility of geological disposal for the long-term management of this waste. These so-called compatibility studies include laboratory water uptake tests at Belgian Nuclear Research Center SCK-CEN, and the development of a coupled CHM formulation for Eurobitum by the International Center for Numerical Methods and Engineering (CIMNE, Polytechnical University of Cataluna, Spain). In the water uptake tests, the osmosis-induced swelling, pressure increase and NaNO{sub 3} leaching of small cylindrical BW samples (diameter 38 mm, height 10 mm) is studied under constant total stress conditions and nearly constant volume conditions; the actual geological disposal conditions should be intermediate between these extremes. Two nearly constant volume tests were stopped after 1036 and 1555 days to characterize the morphology of the hydrated BW samples and to visualize the hydrated part with microfocus X-ray Computer Tomography ({mu}CT) and Environmental Scanning Electron Microscopy (ESEM). In parallel, a coupled CHM formulation is developed that describes chemically and hydraulically coupled flow processes in porous materials with salt crystals, and that incorporates a porosity dependent membrane efficiency, permeability and diffusivity. When Eurobitum BW is hydrated in (nearly) constant volume conditions, the osmosis-induced water uptake results in an increasing pressure to

  17. Osmosis-induced water uptake by Eurobitum bituminized radioactive waste and pressure development in constant volume conditions

    Mariën, A.; Mokni, N.; Valcke, E.; Olivella, S.; Smets, S.; Li, X.

    2013-01-01

    The chemo-hydro-mechanical (CHM) interaction between swelling Eurobitum radioactive bituminized waste (BW) and Boom Clay is investigated to assess the feasibility of geological disposal for the long-term management of this waste. These so-called compatibility studies include laboratory water uptake tests at the Belgian Nuclear Research Center SCK•CEN, and the development of a coupled CHM formulation for Eurobitum by the International Center for Numerical Methods and Engineering (CIMNE, Polytechnical University of Cataluña, Spain). In the water uptake tests, the osmosis-induced swelling, pressure increase and NaNO3 leaching of small cylindrical BW samples (diameter 38 mm, height 10 mm) is studied under constant total stress conditions and nearly constant volume conditions; the actual geological disposal conditions should be intermediate between these extremes. Two nearly constant volume tests were stopped after 1036 and 1555 days to characterize the morphology of the hydrated BW samples and to visualize the hydrated part with microfocus X-ray Computer Tomography (μCT) and Environmental Scanning Electron Microscopy (ESEM). In parallel, a coupled CHM formulation is developed that describes chemically and hydraulically coupled flow processes in porous materials with salt crystals, and that incorporates a porosity dependent membrane efficiency, permeability and diffusivity. When Eurobitum BW is hydrated in (nearly) constant volume conditions, the osmosis-induced water uptake results in an increasing pressure to values that can be (in theory) as high as 42.8 MPa, being the osmotic pressure of a saturated NaNO3 solution. After about four years of hydration in nearly constant volume water uptake tests, pressures up to 20 MPa are measured. During this hydration period only the outer layers with a thickness of 1-2 mm were hydrated (as derived from μCT and ESEM analyses), and only about 10-20% of the initial NaNO3 content was released by the samples. In the studied test

  18. Environmental radioactivity and drinking water supply. Pt. 4

    The enrichment of radioactivity in the sediments reflects the radioactive pollution of the surface waters. As a result of the good retention capacity of the subsoil and the slow water transport in the unsaturated zone the groundwater was protected against the fallout as expected; even in karst areas only very low concentrations of artificial radioactivity were found in the groundwater. In drinking water no artificial radioactivity was detected in most samples. Only in very few cases the radioactivity of drinking water from surface waters exceeded just the detection limits. The investigations confirmed the previous findings, that the exposition path over drinking water may be neglected compared with other exposition routes. (orig./HP)

  19. Artificial Intelligence.

    Lawrence, David R; Palacios-González, César; Harris, John

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve. PMID:26957450

  20. Artificial intelligence

    Duda, Antonín

    2009-01-01

    Abstract : Issue of this work is to acquaint the reader with the history of artificial inteligence, esspecialy branch of chess computing. Main attention is given to progress from fifties to the present. The work also deals with fighting chess programs against each other, and against human opponents. The greatest attention is focused on 1997 and duel Garry Kasparov against chess program Deep Blue. The work is divided into chapters according to chronological order.

  1. Measurements of D-T neutron induced radioactivity in plasma-facing materials and their role in qualification of activation cross-section libraries and codes

    The D-T neutron-induced radioactivity constitutes one of the foremost issues in fusion reactor design. The validation of activation cross-sections and decay data libraries is one of the important requirements for validating ITER design from safety and waste disposal viewpoints. An elaborate, experimental program was initiated in 1988, under USDOE-JAERI collaborative program, to validate the radioactivity codes/libraries. The measurements of decay-γ spectra from irradiated, high purity samples of Al, Si, Ti, V, Cr, Mn-Cu alloy, Fe, Co, Ni, Cu, stainless steel 316 (AISI 316), Zn, Zr, Nb, Mo, In, Sn, Ta, W, and Pb, among others, were conducted under D-T neutron fluences varying from 1.6 x 1010ncm-2 to 6.1 x 1013ncm-2. As many as 14 neutron energy spectra were covered for a number of materials. The analysis of isotopic activities of the irradiated materials using activation cross-section libraries of four leading radioactivity codes, i.e. ACT4/THIDA-2, REAC-3, DKR-ICF, and RACC, has shown large discrepancies among the calculations, on the one hand, and between the calculations and the measurements, on the other. A discussion is also presented on definition and obtention of safety cum quality factors for various activation libraries. (orig.)

  2. Geochemical Effects of Induced Stream-Water and Artificial Recharge on the Equus Beds Aquifer, South-Central Kansas, 1995-2004

    Schmidt, Heather C. Ross; Ziegler, Andrew C.; Parkhurst, David L.

    2007-01-01

    Artificial recharge of the Equus Beds aquifer is part of a strategy implemented by the city of Wichita, Kansas, to preserve future water supply and address declining water levels in the aquifer of as much as 30 feet caused by withdrawals for water supply and irrigation since the 1940s. Water-level declines represent a diminished water supply and also may accelerate migration of saltwater from the Burrton oil field to the northwest and the Arkansas River to the southwest into the freshwater of the Equus Beds aquifer. Artificial recharge, as a part of the Equus Beds Ground-Water Recharge Project, involves capturing flows larger than base flow from the Little Arkansas River and recharging the water to the Equus Beds aquifer by means of infiltration or injection. The geochemical effects on the Equus Beds aquifer of induced stream-water and artificial recharge at the Halstead and Sedgwick sites were determined through collection and analysis of hydrologic and water-quality data and the application of statistical, mixing, flow and solute-transport, and geochemical model simulations. Chloride and atrazine concentrations in the Little Arkansas River and arsenic concentrations in ground water at the Halstead recharge site frequently exceeded regulatory criteria. During 30 percent of the time from 1999 through 2004, continuous estimated chloride concentrations in the Little Arkansas River at Highway 50 near Halstead exceeded the Secondary Drinking-Water Regulation of 250 milligrams per liter established by the U.S. Environmental Protection Agency. Chloride concentrations in shallow monitoring wells located adjacent to the stream exceeded the drinking-water criterion five times from 1995 through 2004. Atrazine concentrations in water sampled from the Little Arkansas River had large variability and were at or near the drinking-water Maximum Contaminant Level of 3.0 micrograms per liter as an annual average established by the U.S. Environmental Protection Agency. Atrazine

  3. Does Artificial Ascites Induce the Heat-Sink Phenomenon during Percutaneous Radiofrequency Ablation of the Hepatic Subcapsular Area?: an in vivo Experimental Study Using a Rabbit Model

    To evaluate the effect of the heat-sink phenomenon induced by artificial ascites on the size of the ablation zone during percutaneous radiofrequency (RF) ablation of the hepatic subcapsular area in an in vivo rabbit model. A total of 21 percutaneous rabbit liver RF ablations were performed with and without artificial ascites (5% dextrose aqueous solution). The rabbits were divided into three groups: a) control group (C, n = 7); b) room temperature ascites group (R, n = 7); and c) warmed ascites group (W, n = 7). The tip of a 1 cm, internally cooled electrode was placed on the subcapsular region of the hepatic dome via ultrasound guidance, and ablation was continued for 6 min. Changes in temperature of the ascites were monitored during the ablation. The size of the ablation zones of the excised livers and immediate complications rates were compared statistically between the groups (Mann-Whitney U test, Kruskal-Wallis test, linear-by-linear association, p = 0.05). One rabbit from the 'W' group expired during the procedure. In all groups, the ascites temperatures approached their respective body temperatures as the ablations continued; however, a significant difference in ascites temperature was found between groups 'W' and 'R' throughout the procedures (39.2± 0.4 .deg. C in group W and 33.4±4.3 .deg. C in group R at 6 min, p = 0.003). No significant difference was found between the size of the ablation zones (782.4±237.3 mL in group C, 1,172.0±468.9 mL in group R, and 1,030.6±665.1 mL in group W, p = 0.170) for the excised liver specimens. Diaphragmatic injury was identified in three of seven cases (42.9%) upon visual inspection of group 'C' rabbits (p = 0.030). Artificial ascites are not likely to cause a significant heat-sink phenomenon in the percutaneous RF ablation of the hepatic subcapsular region

  4. Does Artificial Ascites Induce the Heat-Sink Phenomenon during Percutaneous Radiofrequency Ablation of the Hepatic Subcapsular Area?: an in vivo Experimental Study Using a Rabbit Model

    Kim, Young Sun; Rhim, Hyun Chul; Choi, Dong Il; Lim, Hyo K. [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2009-02-15

    To evaluate the effect of the heat-sink phenomenon induced by artificial ascites on the size of the ablation zone during percutaneous radiofrequency (RF) ablation of the hepatic subcapsular area in an in vivo rabbit model. A total of 21 percutaneous rabbit liver RF ablations were performed with and without artificial ascites (5% dextrose aqueous solution). The rabbits were divided into three groups: a) control group (C, n = 7); b) room temperature ascites group (R, n = 7); and c) warmed ascites group (W, n = 7). The tip of a 1 cm, internally cooled electrode was placed on the subcapsular region of the hepatic dome via ultrasound guidance, and ablation was continued for 6 min. Changes in temperature of the ascites were monitored during the ablation. The size of the ablation zones of the excised livers and immediate complications rates were compared statistically between the groups (Mann-Whitney U test, Kruskal-Wallis test, linear-by-linear association, p = 0.05). One rabbit from the 'W' group expired during the procedure. In all groups, the ascites temperatures approached their respective body temperatures as the ablations continued; however, a significant difference in ascites temperature was found between groups 'W' and 'R' throughout the procedures (39.2+- 0.4 .deg. C in group W and 33.4+-4.3 .deg. C in group R at 6 min, p = 0.003). No significant difference was found between the size of the ablation zones (782.4+-237.3 mL in group C, 1,172.0+-468.9 mL in group R, and 1,030.6+-665.1 mL in group W, p = 0.170) for the excised liver specimens. Diaphragmatic injury was identified in three of seven cases (42.9%) upon visual inspection of group 'C' rabbits (p = 0.030). Artificial ascites are not likely to cause a significant heat-sink phenomenon in the percutaneous RF ablation of the hepatic subcapsular region

  5. Radioactivity. Centenary of radioactivity discovery; Radioactivite. Centenaire de la decouverte de la radioactivite

    Charpak, G. [Academie des Sciences, 75 - Paris (France); Tubiana, M. [Academie de Medecine, 75 - Paris (France); Bimbot, R. [Institut National de Physique Nucleaire et de Physique des Particules (India2P3), 75 - Paris (France)

    1997-12-31

    This small booklet was edited for the occasion of the exhibitions of the celebration of the centenary of radioactivity discovery which took place in various locations in France from 1996 to 1998. It recalls some basic knowledge concerning radioactivity and its applications: history of discovery, atoms and isotopes, radiations, measurement of ionizing radiations, natural and artificial radioactivity, isotope dating and labelling, radiotherapy, nuclear power and reactors, fission and fusion, nuclear wastes, dosimetry, effects and radioprotection. (J.S.)

  6. The effect of an extended artificial photoperiod and gonadotrophin-releasing hormone infusions in inducing fertile oestrus in anoestrous mares.

    Lowis, T C; Hyland, J H

    1991-12-01

    The occurrence of fertile oestrus early in the breeding season is of paramount importance to the Thoroughbred industry to facilitate early conception. This paper compares 2 techniques for inducing fertile oestrus in anoestrous mares using either an extended photoperiod alone or together with gonadotrophin-releasing hormone (GnRH) infusions. Eleven mares were placed under conditions of 16 h light and 8 h darkness and 5 of these were implanted with osmotic minipumps delivering approximately 100 ng GnRH/kg/h for 28 days (treated mares). The treated mares ovulated 27.7 days earlier than and conceived 32 days earlier than the 6 mares not given GnRH. GnRH-induced ovulations were followed by a competent luteal phase. The combination of GnRH pumps implanted 2 weeks before commencement of service together with extended photoperiod from July 1 has promise in assisting the stud breeder to improve reproductive efficiency on commercial stud farms. PMID:1807248

  7. Psychologically induced cooling of a specific body part caused by the illusory ownership of an artificial counterpart

    Moseley, G. Lorimer; Olthof, Nick; Venema, Annemeike; Don, Sanneke; Wijers, Marijke; Gallace, Alberto; Spence, Charles

    2008-01-01

    The sense of body ownership represents a fundamental aspect of our self-awareness, but is disrupted in many neurological, psychiatric, and psychological conditions that are also characterized by disruption of skin temperature regulation, sometimes in a single limb. We hypothesized that skin temperature in a specific limb could be disrupted by psychologically disrupting the sense of ownership of that limb. In six separate experiments, and by using an established protocol to induce the rubber h...

  8. Probabilistic siting analysis of nuclear power plants emphasizing atmospheric dispersion of radioactive releases and radiation-induced health effects

    A presentation is made of probabilistic evaluation schemes for nuclear power plant siting. Effects on health attributable to ionizing radiation are reviewed, for the purpose of assessment of the numbers of the most important health effect cases in light-water reactor accidents. The atmospheric dispersion of radioactive releases from nuclear power plants is discussed, and there is presented an environmental consequence assessment model in which the radioactive releases and atmospheric dispersion of the releases are treated by the application of probabilistic methods. In the model, the environmental effects arising from exposure to radiation are expressed as cumulative probability distributions and expectation values. The probabilistic environmental consequence assessment model has been applied to nuclear power plant site evaluation, including risk-benefit and cost-benefit analyses, and the comparison of various alternative sites. (author)

  9. Resent Progress in Research on Calibration Instrument for Radioactive Aerosol Monitor

    CHEN; Xi-lin; CHEN; Yong-yong; WU; Chang-ping; XING; Yu; MENG; Jun; YANG; Qiao-ling

    2013-01-01

    Radioactive aerosol monitors are widely used in monitoring the radioactivity concentration of the artificial nuclides in gaseous effluents from the nuclear facilities.An on-developing calibration instrument for radioactive aerosol monitors consists of an α and β aerosol generating unit,aerosol transferring unit,measurement unit of radioactivity concentration of aerosol for instruments calibrated and the waste gas

  10. Evaluation of genetic variability for heading date and height in triticale obtained by induced mutations and artificial crosses

    The adjustment of adaptive characters such as heading date and height, allows one to arrange successive cultures and to apply efficient agronomic techniques, resulting in productivity increase. Methods that increase genetic variability have great significance in plant breeding, once they amplify the opportunities for selecting superior genotypes. The aim of this study was to evaluate the effect of induced mutations and reciprocal crosses in families segregating for heading date and height and to analyze the correlation between these characters. The populations were obtained from reciprocal crosses and induced mutation with gamma radiation. In the latter, radiation dosages of 0, 5, 10, 20, 40 kR were obtained from exposition to Cobalt - 60. Changes in the mean and variance in two triticale genotypes Triticale BR4 e EMBRAPAI8, were analyzed. The results obtained indicated families with wide segregation patterns for heading date and height and also suggested the possibility to identify families with distinct values compared to the control population for both characters and both genotypes. There was a tendency to reductions in height and increases in heading date for the families evaluated. However, there was not an expressive correlation between heading date and height for the majority of the treatments, therefore allowing the breeder to select plant types adapted to the environment of cultivation. (author)

  11. Radioactivity and food preservation

    In food irradiation, electrons or electromagnetic radiation are used to destroy microorganisms and insects or to prevent seed germination. The economic advantages and health benefits of sterilizing food in this manner are clear, and numerous studies have confirmed that under strictly controlled conditions no undesirable changes or induced radioactivity are produced in the irradiated food

  12. Four decades of opposing natural and human-induced artificial selection acting on Windermere pike (Esox lucius).

    Carlson, Stephanie M; Edeline, Eric; Asbjørn Vøllestad, L; Haugen, Thrond O; Winfield, Ian J; Fletcher, Janice M; Ben James, J; Stenseth, Nils Chr

    2007-06-01

    The ability of natural selection to drive local adaptation has been appreciated ever since Darwin. Whether human impacts can impede the adaptive process has received less attention. We tested this hypothesis by quantifying natural selection and harvest selection acting on a freshwater fish (pike) over four decades. Across the time series, directional natural selection tended to favour large individuals whereas the fishery targeted large individuals. Moreover, non-linear natural selection tended to favour intermediate sized fish whereas the fishery targeted intermediate sized fish because the smallest and largest individuals were often not captured. Thus, our results unequivocally demonstrate that natural selection and fishery selection often acted in opposite directions within this natural system. Moreover, the two selective factors combined to produce reduced fitness overall and stronger stabilizing selection relative to natural selection acting alone. The long-term ramifications of such human-induced modifications to adaptive landscapes are currently unknown and certainly warrant further investigation. PMID:17498150

  13. The development neurotoxicity of ethanol: Cerebral cortical cholinergic alterations induced in artificially reared rats exposed to ethanol during the brain growth spurt

    It is hypothesized that cerebral cortical cholinergic neurotransmitter system alterations are induced by ethanol exposure during the vulnerable period of rapid brain growth. To test this proposal, on postnatal (PN) day 4, male Sprague Dawley rat pups were randomly assigned to either mother raised control (MRC) or artificially reared (AR) experimental groups. AR, ethanol-exposed (EE) pups received a liquid diet containing either 3%, 4%, or 5% (w/v) ethanol, while AR, cup-control (CC) pups isovolumetrically received an isocaloric, glucose-substituted diet. Acute effects of AR (CC vs MRC) and EE (EE vs CC) were determined in groups of pups sacrificed immediately following the termination of AR on PN8. Other groups of neonates were returned to foster dams on PN8 and maternally reared until sacrifice on PN20 to detect persistent or latent alternations. Although AR failed to perturb muscarinic receptor density at either age of assessment, it acutely and persistently decreased receptor affinity for (3H)QNB, and also the activities of both acetylcholinesterase and choline acetyltransferase

  14. Fast identification of biominerals by means of stand-off laser‐induced breakdown spectroscopy using linear discriminant analysis and artificial neural networks

    The goal of this paper is to compare two selected statistical techniques used for identification of archeological materials merely on the base of their spectra obtained by stand-off laser-induced breakdown spectroscopy (stand-off LIBS). Data processing using linear discriminant analysis (LDA) and artificial neural networks (ANN) were applied on spectra of 18 different samples, some of them archeological and some recent, containing 7 types of material (i.e. shells, mortar, bricks, soil pellets, ceramic, teeth and bones). As the input data PCA scores were taken. The intended aim of this work is to create a database for simple and fast identification of archeological or paleontological materials in situ. This approach can speed up and simplify the sampling process during archeological excavations that nowadays tend to be quite damaging and time-consuming. - Highlights: ► We use statistical techniques for identification of archeological materials. ► Input data for LDA and ANN are PC scores counted from stand-off LIBS spectra. ► The method used for identification of archeological materials provides good results. ► After recording more spectra we can get useful tool for rapid analysis in situ.

  15. Fast identification of biominerals by means of stand-off laser-induced breakdown spectroscopy using linear discriminant analysis and artificial neural networks

    Vitkova, Gabriela [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Novotny, Karel, E-mail: codl@sci.muni.cz [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Prokes, Lubomir [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Hrdlicka, Ales [Central European Institute of Technology, CEITEC MU, Masaryk University (Czech Republic); Kaiser, Jozef [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic); X-ray micro CT and nano CT research group, CEITEC-Central European Institute of Technology, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic); Novotny, Jan [X-ray micro CT and nano CT research group, CEITEC-Central European Institute of Technology, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic); Malina, Radomir; Prochazka, David [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic)

    2012-07-15

    The goal of this paper is to compare two selected statistical techniques used for identification of archeological materials merely on the base of their spectra obtained by stand-off laser-induced breakdown spectroscopy (stand-off LIBS). Data processing using linear discriminant analysis (LDA) and artificial neural networks (ANN) were applied on spectra of 18 different samples, some of them archeological and some recent, containing 7 types of material (i.e. shells, mortar, bricks, soil pellets, ceramic, teeth and bones). As the input data PCA scores were taken. The intended aim of this work is to create a database for simple and fast identification of archeological or paleontological materials in situ. This approach can speed up and simplify the sampling process during archeological excavations that nowadays tend to be quite damaging and time-consuming. - Highlights: Black-Right-Pointing-Pointer We use statistical techniques for identification of archeological materials. Black-Right-Pointing-Pointer Input data for LDA and ANN are PC scores counted from stand-off LIBS spectra. Black-Right-Pointing-Pointer The method used for identification of archeological materials provides good results. Black-Right-Pointing-Pointer After recording more spectra we can get useful tool for rapid analysis in situ.

  16. Fluorescent turn-on sensing of bacterial lipopolysaccharide in artificial urine sample with sensitivity down to nanomolar by tetraphenylethylene based aggregation induced emission molecule.

    Jiang, Guoyu; Wang, Jianguo; Yang, Yang; Zhang, Guanxin; Liu, Yaling; Lin, He; Zhang, Guilan; Li, Yongdong; Fan, Xiaolin

    2016-11-15

    A tetraphenylethylene based aggregation induced emission (AIE) probe, TPEPyE, bearing a positively charged pyridinium pendant was designed and synthesized. The positively charged TPEPyE can efficiently bind to the negatively charged lipopolysaccharide (LPS) through electrostatic interactions between the two oppositely charged species. As a result, upon the addition of LPS into the PBS solution of TPEPyE, this probe aggregated immediately onto the surface of LPS and resulted over 22-fold of fluorescence enhancement. TPEPyE exhibited good selectivity and high sensitivity toward LPS in PBS buffer solution and the detection limit was calculated to be 370 pM (3.7ng/mL). More notably, TPEPyE also retained good sensitivity and selectivity in artificial urine system (with much higher ionic strength) with the detection limit down to nanomolar. Moreover, this probe can also make a distinction between gram-positive bacteria Staphylococcus aureus (S. aureus) and gram-negative bacteria Escherichia coli (E. coli), making it a promising sensor for clinical monitoring of urinary tract infections. PMID:27155117

  17. Autonomous oscillation/separation of cell density artificially induced by optical interlink feedback as designed interaction between two isolated microalgae chips

    Ozasa, Kazunari; Won, June; Song, Simon; Maeda, Mizuo

    2016-04-01

    We demonstrate a designed interaction between two isolated cell populations of Euglena gracilis and Chlamydomonas reinhardtii, separately confined in two 25-square micro-aquariums of lab-on-chip size. The interaction was realized by interlinking two identical optical feedback systems, which measured the cell distribution. To analyze the cell populations, we measured the cell distribution in the 25 squares and irradiated the cells with a blue light pattern as an external stimulus. The cell distribution dataset was exchanged between the two systems. Governed by a designed interaction algorithm, the feedback systems produced a dynamic blue light illumination pattern that evoked the photophobic responses of both species. We also induced autonomous cell density oscillation and cell distribution separation and clustering, and analyzed how the types and diversities of the photophobic responses affected the oscillation period and separation and clustering. We conclude that artificial interlink feedback is a promising method for investigating diverse cell–cell interactions in ecological communities, and for developing soft-computing applications with living cells.

  18. Cloning of the Koi Herpesvirus Genome as an Infectious Bacterial Artificial Chromosome Demonstrates That Disruption of the Thymidine Kinase Locus Induces Partial Attenuation in Cyprinus carpio koi▿

    Costes, B.; Fournier, G.; Michel, B.; Delforge, C.; Raj, V. Stalin; Dewals, B.; Gillet, L.; Drion, P.; Body, A.; Schynts, F.; Lieffrig, F.; Vanderplasschen, A.

    2008-01-01

    Koi herpesvirus (KHV) is the causative agent of a lethal disease in koi and common carp. In the present study, we describe the cloning of the KHV genome as a stable and infectious bacterial artificial chromosome (BAC) clone that can be used to produce KHV recombinant strains. This goal was achieved by the insertion of a loxP-flanked BAC cassette into the thymidine kinase (TK) locus. This insertion led to a BAC plasmid that was stably maintained in bacteria and was able to regenerate virions when permissive cells were transfected with the plasmid. Reconstituted virions free of the BAC cassette but carrying a disrupted TK locus (the FL BAC-excised strain) were produced by the transfection of Cre recombinase-expressing cells with the BAC. Similarly, virions with a wild-type revertant TK sequence (the FL BAC revertant strain) were produced by the cotransfection of cells with the BAC and a DNA fragment encoding the wild-type TK sequence. Reconstituted recombinant viruses were compared to the wild-type parental virus in vitro and in vivo. The FL BAC revertant strain and the FL BAC-excised strain replicated comparably to the parental FL strain. The FL BAC revertant strain induced KHV infection in koi carp that was indistinguishable from that induced by the parental strain, while the FL BAC-excised strain exhibited a partially attenuated phenotype. Finally, the usefulness of the KHV BAC for recombination studies was demonstrated by the production of an ORF16-deleted strain by using prokaryotic recombination technology. The availability of the KHV BAC is an important advance that will allow the study of viral genes involved in KHV pathogenesis, as well as the production of attenuated recombinant candidate vaccines. PMID:18337580

  19. Environmental radioactivity and radiation exposure

    In 1977 population exposure in the Federal Republic of Germany has not changed as compared to the previous years. The main share of the total exposure, nearly two thirds, is attributed to natural radioactive substances and cosmic radiation. The largest part (around 85%) of the artificial radiation exposure is caused by X-ray diagnostics. In comparison to this, radiation exposure from application of ionizing radiation in medical therapy, use of radioactive material in research and technology, or from nuclear facilities is small. As in the years before, population exposure caused by nuclear power plants and other nuclear facilities is distinctly less than 1% of the natural radiation exposure. This is also true for the average radiation exposure within a radius of 3 km around nuclear facilities. On the whole, the report makes clear that the total amount of artificial population exposure will substantially decrease only if one succeeds in reducing the high contribution to the radiation exposure caused by medical measures. (orig.)

  20. Halogenated solvent interactions with N,N-dimethyltryptamine: formation of quaternary ammonium salts and their artificially induced rearrangements during analysis.

    Brandt, Simon D; Martins, Cláudia P B; Freeman, Sally; Dempster, Nicola; Riby, Philip G; Gartz, Jochen; Alder, John F

    2008-07-01

    The psychoactive properties of N,N-dimethyltryptamine (DMT) 1a are known to induce altered states of consciousness in humans. This particular attribute attracts great interest from a variety of scientific and also clandestine communities. Our recent research has confirmed that DMT reacts with dichloromethane (DCM), either as a result of work-up or storage to give a quaternary N-chloromethyl ammonium salt 2a. Furthermore, this was observed to undergo rearrangement during analysis using gas chromatography-mass spectrometry (GC-MS) with products including 3-(2-chloroethyl)indole 3 and 2-methyltetrahydro-beta-carboline 4 (2-Me-THBC). This study further investigates this so far unexplored area of solvent interactions by the exposure of DMT to other halogenated solvents including dibromomethane and 1,2-dichloroethane (DCE). The N-bromomethyl- and N-chloroethyl quaternary ammonium derivatives were subsequently characterised by ion trap GC-MS in electron and chemical ionisation tandem MS mode and by NMR spectroscopy. The DCE-derived derivative formed at least six rearrangement products in the total ion chromatogram. Identification of mass spectrometry generated by-products was verified by conventional or microwave-accelerated synthesis. The use of deuterated DCM and deuterated DMT 1b provided insights into the mechanism of the rearrangements. The presence of potentially characteristic marker molecules may allow the identification of solvents used during the manufacture of controlled substances, which is often neglected since these are considered inert. PMID:18455334

  1. Effect of photoperiod on endocrine profiles and vitellogenin expression in European eels Anguilla anguilla during artificially induced ovarian development.

    Parmeggiani, A; Govoni, N; Zannoni, A; Di Biase, A; Sirri, R; Forni, M; Mandelli, M; Mordenti, O

    2015-03-01

    The aim of this work was to determine the effects of dark and light conditions on the E2, testosterone and thyroid hormones levels and on the gene expression levels (vitellogenin 1, vitellogenin 2, and estradiol receptor one) in European eels (Anguilla anguilla) during ovarian development induced by increasing doses of carp pituitary extracts (CPEs). The subjects were divided into 2 groups: 14-hour light:10-hour dark (Light Group) and 24-hour darkness (Dark Group). All the eels received intramuscular injections with CPE at a dosage of 10 mg/kg body weight (BW) once a week for the first 3 weeks, 20 mg/kg BW fourth-sixth week, 30 mg/kg BW seventh-ninth week, and 40 mg/kg up to the end of the experiment (13th week). Vitellogenin and estradiol receptor expression levels did not show significant differences between the two housing conditions whereas in both groups vitellogenin mRNA increased starting from first CPE injection. Testosterone and 17-beta estradiol plasma levels were significantly greater in the Dark Group compared with the Light Group starting from the ninth and the 13th week, respectively. These results suggest that darkness could be a useful variable for standardizing gonadal maturation in eels kept in captivity. PMID:25459031

  2. Radioactive Wastes.

    Choudri, B S; Baawain, Mahad

    2015-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2014. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes. PMID:26420096

  3. Radioactive Wastes.

    Choudri, B S; Baawain, Mahad

    2016-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2015. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes. PMID:27620100

  4. First artificial radionuclides for Czechoslovakia after Word War II. Pt. 1

    This first contribution in the 2-part series describes the following topics: Discovery of artificial radioactivity and first artificial radionuclides; Czechoslovak reflection of the development over the world; Opportunities for obtaining artificial radioisotopes from the USA; Response to the US offer by Czechoslovak physicians; and Steps taken by the Ministry of Health. (orig.)

  5. Concentrating Radioactivity

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  6. Simulated Radioactivity

    Boettler, James L.

    1972-01-01

    Describes the errors in the sugar-cube experiment related to radioactivity as described in Project Physics course. The discussion considers some of the steps overlooked in the experiment and generalizes the theory beyond the sugar-cube stage. (PS)

  7. Radioactivity Calculations

    Onega, Ronald J.

    1969-01-01

    Three problems in radioactive buildup and decay are presented and solved. Matrix algebra is used to solve the second problem. The third problem deals with flux depression and is solved by the use of differential equations. (LC)

  8. Radionuclides induced by environmental neutrons. Discovery of natural radioactive Eu and Co isotopes and their contribution to the evaluation of Atomic-bombing neutrons in Hiroshima and Nagasaki

    Komura, Kazuhisa [Kanazawa Univ., Low Level Radioactivity Lab., Tatsunokuchi, Ishikawa (Japan); Yousef, Ahmed M. [South Valley Univ. (Egypt)

    2001-06-01

    Radioactive europium and cobalt isotopes induced by environmental neutrons have been discovered by low-background Ge detector installed in Ogoya underground laboratory. Specific activities of {sup 152}Eu, {sup 154}Eu and {sup 155}Eu and {sup 60}Co were measured for recent and old europium and cobalt reagents. Observed activities are 0.06-0.52 dpm g{sup -1} for {sup 152}Eu, 0.09-0.16 dpm g{sup -1} for {sup 154}Eu and 0.005-0.16 dpm g{sup -1} for {sup 155}Eu and 0.007-0.083 dpm g{sup -1} for {sup 60}Co. Contribution of natural {sup 152}Eu and {sup 60}Co in Atomic-bomb exposed samples are found to be negligible low and less than 10%, respectively. (author)

  9. Measurements of D-T neutron induced radioactivity in plasma-facing materials and their role in qualification of activation cross-section libraries and codes

    USDOE/JAERI collaborative program on induced radioactivity measurements has been spread over last five years and has covered, among others, a large number of plasma facing materials of interest to D-T fusion reactors, including ITER and DEMO. The experiments have consisted of irradiation of high purity material samples in a range of neutron energy spectra in simulated fusion environments of prototypical blanket assemblies driven by D-T neutrons at FNS/JAERI. A typical sample measured 10 mm in diameter by 1 mm thickness, and the neutron fluence ranged from ∼1010 n/cm2 to ∼1014 n/cm2, over an irradiation period of 30 m and 10 h. The irradiated samples were then cooled for varying times, from ∼10 m to ∼3 weeks, and their activity was derived by counting associated γ-rays with intrinsic germanium detectors

  10. Reliability assessment of high energy particle induced radioactivity calculation code DCHAIN-SP 2001 by analysis of integral activation experiments with 14 MeV neutrons

    Reliability assessment for the high energy particle induced radioactivity calculation code DCHAIN-SP 2001 was carried out through analysis of integral activation experiments with 14-MeV neutrons aiming at validating the cross section and decay data revised from previous version. The following three kinds of experiments conducted at the D-T neutron source facility, FNS, in JAERI were employed: (1) the decay gamma-ray measurement experiment for fusion reactor materials, (2) the decay heat measurement experiment for 32 fusion reactor materials, and (3) the integral activation experiment on mercury. It was found that the calculations with DCHAIN-SP 2001 predicted the experimental data for (1) - (3) within several tens of percent. It was concluded that the cross section data below 20 MeV and the associated decay data as well as the calculation algorithm for solving the Beteman equation that was the master equation of DCHAIN-SP were adequate. (author)

  11. Radionuclides induced by environmental neutrons. Discovery of natural radioactive Eu and Co isotopes and their contribution to the evaluation of Atomic-bombing neutrons in Hiroshima and Nagasaki

    Radioactive europium and cobalt isotopes induced by environmental neutrons have been discovered by low-background Ge detector installed in Ogoya underground laboratory. Specific activities of 152Eu, 154Eu and 155Eu and 60Co were measured for recent and old europium and cobalt reagents. Observed activities are 0.06-0.52 dpm g-1 for 152Eu, 0.09-0.16 dpm g-1 for 154Eu and 0.005-0.16 dpm g-1 for 155Eu and 0.007-0.083 dpm g-1 for 60Co. Contribution of natural 152Eu and 60Co in Atomic-bomb exposed samples are found to be negligible low and less than 10%, respectively. (author)

  12. Artificial Economy

    Alexandru JIVAN

    2011-08-01

    Full Text Available This paper proposes to eliminate, a routine in the economic thinking, claimed to be responsible for the negative essence of economic developments, from the point of view, of the ecological implications (employment in the planetary ecosystem. The methodological foundations start from the natural origins of the functionality of the human economic society according to the originary physiocrat liberalism, and from specific natural characteristics of the humankind. This paper begins with a comment-analysis of the difference between natural and artificial within the economy, and then explains some of the most serious diversions from the natural essence of economic liberalism. It shall be explained the original (heterodox interpretation of the Classical political economy (economics, by making calls to the Romanian economic thinking from aggravating past century. Highlighting the destructive impact of the economy - which, under the invoked doctrines, we call unnatural - allows an intuitive presentation of a logical extension of Marshall's market price, based on previous research. Besides the doctrinal arguments presented, the economic realities inventoried along the way (major deficiencies and effects, determined demonstrate the validity of the hypothesis of the unnatural character and therefore necessarily to be corrected, of the concept and of the mechanisms of the current economy.The results of this paper consist of original heterodox methodspresented, intuitive or developed that can be found conclusively within the key proposals for education and regulation.

  13. Experimental investigation of radioactivity induced in the fusion power plant structural material SiC and in the breeder material Li4SiO4 by 14-MeV neutrons

    The radioactivity induced by neutrons in the materials of fusion power plants is a focus of investigations dedicated to safety and environmental assessments of fusion power. The greatest part of the radioactivity is produced by two components of the neutron flux spectrum, by thermal neutrons and by the 14-MeV DT fusion neutrons. The low-activation material SiC and the tritium-generating material Li4SiO4 were irradiated with 14-MeV neutrons, and the γ-activity induced was measured several times during the decay. The results were analysed with the European Activation System EASY-99 with respect to short-term and long-term radioactivity

  14. Radiation protection. Radioactivity and health

    This booklet makes an attempt at elucidating the mutual influence of radioactivity and health in a way which is understandable to the non-expert. The basics of radioactivity are briefly explained by way of introduction, the next item to be described is exposure of man to natural and artificial radiation. Somatic and genetic effects of radiation on man are subsequently discussed. The whole area of radioecology - starting with radioactive discharge from nuclear plants and going on to the determination of man's exposure to radiation - is covered and supplemented by a description of the risks of radiation therapy. All this serves to describe the results of long-term research on questions of the radiobiological risks in an understandable way and provide useful information about this eminently important area. (orig./HP)

  15. Measurement of radioactivity in steel

    Even after the control of scrap deliveries, there remains a small risk that the radioactive contaminated scrap passes the detecting devices. Therefore, the chemical laboratory takes a role to measure each heat for the absence of artificial radioactive nuclides with a gamma spectrometer equipped with NaI-detector. As the measurement must be performed in sequence with the steel production process, the allowable time for the measurement is quite limited. On the other hand, there could be still some possibility that background radiation might be present as the samples may contain some natural radioactivity. The task is how to differentiate the nature of radioactivity between naturally remaining radioactivity within safe limit and artificial nuclides present in the sample at a low level even though a very small amount of radioactivity could be detected in short time in both cases. We have set the alarm limit to 0.1 Bq/g for Co-60 as indicating nuclide. This limit is set more than 4 s (s = standard deviation) from the average background radiation. Therefore, false alarms are quite improbable. Strategy: The NaI gamma spectrometer performs a gross gamma measurement but it can not differentiate the nature of the nuclides present. If the alarm limit is hurt, the sample is measured on a high resolution gamma spectrometer with Ge-detector for identification of the gamma emitting nuclides. Calibration: Even though no appropriate international standards are adapted and no commercial measuring equipment is commercially available, the desired standard should contain Co-60 in the order of 1 to 100 Bq/g. The presence of other gamma emitting nuclides is desirable. In the Workshop we will present how to surmount this difficulty. (author)

  16. Walter Russell's concepts as the basis for an alternative view on radioactivity induced oxygen-ozone depletion and food chain pollution; and as the basis for alternative fuels, materials, energy production, and radioactive waste cleanup

    The following topics with supporting data will be presented: The transmutation of atmospheric nitrogen into carbon 14 and tritium via radioactivity as a source of omnipresent food and water pollution, and the possible correlation of oxygen transmutation into carbon 14 and tritium by the same mechanisms as well as into sulfur. Walter Russell's four pole field dual polarity control as a basis for transmutation will be discussed with reference to past and contemporary results of experimentation on this basis. Extension of the concepts into free hydrogen energy fuel, nitrogen fertilizers, other materials production,and transmutation of radioactive wastes into non radioactive elements will be discussed

  17. Ambient radioactivity levels and radiation doses. Annual report 2013; Umweltradioaktivitaet und Strahlenbelastung. Jahresbreicht 2013

    Hachenberger, Claudia; Trugenberger-Schnabel, Angela; Loebke-Reinl, Angelika; Peter, Josef (comps.) [Bundesamt fuer Strahlenschutz, Salzgitter (Germany)

    2015-04-15

    The report on environmental radioactivity and radiation exposure 2013 includes data concerning the following issues: sources of natural and artificial radioactivity, radon in buildings, radioactive materials in construction materials and industrial products, nuclear weapon tests, the consequences of reactor accidents in Chernobyl and Fukushima, nuclear facilities, occupational exposure, radiation exposure from medical applications, handling of radioactive materials in research and technology, radioactive wastes, radiation accidents and specific incidents.

  18. Gamma-H2AX as a biomarker of DNA damage induced by ionizing radiation in targeted and bystander human artificial skin models and peripheral blood lymphocytes

    Redon, Christophe; Dickey, Jennifer; Bonner, William; Sedelnikova, Olga

    Ionizing radiation (IR) exposure is inevitable. In addition to exposure from cosmic rays, the sun and radioactive substances, modern society has created new sources of radiation exposure such as space and high altitude journeys, X-ray diagnostics, radiological treatments and the increasing threat of radiobiological terrorism. For these reasons, a reliable, reproducible and sensitive assessment of dose and time exposure to IR is essential. We developed a minimally invasive diagnostic test for IR exposure based on detection of a phosphorylated variant of histone H2AX (gamma-H2AX), which occurs specifically at sites of DNA double-strand breaks (DSBs). The phosphorylation of thousands of H2AX molecules forms a gamma-H2AX focus in the chromatin flanking the DSB site that can be detected in situ. We analyzed gamma- H2AX focus formation in both directly irradiated cells as well as in un-irradiated "bystanders" in close contact with irradiated cells. In order to insure minimal invasiveness, we examined commercially available artificial skin models as a surrogate for human skin biopsies as well as peripheral blood lymphocytes. In human skin models, cells in a thin plane were microbeamirradiated and gamma-H2AX formation was measured both in irradiated and in distal bystander cells over time. In irradiated cells DSB formation reached a maximum at 15-30 minutes post- IR and then declined within several hours; all cells were affected. In marked contrast, the incidence of DSBs in bystander cells reached a maximum by 12-48 hours post-irradiation, gradually decreasing over the 7 day time course. At the maxima, 40-60% of bystander cells were affected. Similarly, we analyzed blood samples exposed to IR ex vivo at doses ranging from 0.02 to 3 Gy. The amount of DNA damage was linear in respect to radiation dose and independent of the age or sex of the blood donor. The method is highly reproducible and highly sensitive. In directly irradiated cells, the number of gamma-H2AX foci peaked

  19. Theoretical evaluation of induced radioactivity in food products by electron — or X-ray beam sterilization

    Leboutet, H.; Aucouturier, J.

    We evaluate first the energy density for electrons or X-ray beams necessary to produce a reference level of 1 kilogray at the maximum of dose, as a function of energy, for electrons and bremsstrahlung photons ( BX rays), based on experimental data obtained on radio-therapy beams, from 4 to 32 MeV, and irradiation beams from production plant CARIC. Then from the production of neutrons on the tungsten target and from (γ n) reactions on the deuterium content of the irradiated food, the slowing down and capture of these neutrons is estimated. Radioisotopes can be produced by (γ n) reactions on iodine, and to a lesser extent on tin, lead, barium, etc., but the major contribution is neutron activation, where the more critical elements are sodium, chlorine, potassium, magnesium, phosphorus, calcium. Induced activity is compared to natural activity coming from potassium 40, carbon 14 and radium, contained in all foods. We conclude that for electrons up to 1 Mrad the induced activity remains of the order of a few percent of natural activity, for energies below 10-11 MeV. Bremsstrahlung X-ray irradiations can give comparable levels as soon as the energy of the generating electron beam is above 3 MeV. The induced activity decays within a few days. There is only a small increase of induced activity as the energy changes from 5 to 10 MeV, for the same total applied dose.

  20. Determination of pharmacokinetic processes in body organs on the basis of the box model and, by analogy, of laws of radioactive disintegration of naturally occurring and artificially activated isotope families

    The research work described is based on the simple law of degradation and disintegration for pharmaceutical substances. The transport, storage and, possibly, accumulation of beneficial and harmful pharmaceuticals in the organs of the human body are analysed using the box model. The studies are not restricted to asymptotic conditions occurring after continuous treatment with a particular drug but also investigate into the so-called stabilisation phase immediately after the beginning of medication, which is described mathematically. This phase is shown to be subject to a set of rules that are much more complex than those responsible for asymptotic substance levels. The analytical procedures used here are described on the basis of typical cases drawn from medical practice. The laws derived from these observations can, by analogy, also be applied to the radioactive disintegration of isotope families. They also permit formulas to be determined for the activity of multiple-link chain members. The report proceeds by discussing cases, where the baseline substance is the result of nuclear chain reacting. The last issue to be treated within the scope of this study is the radioactive disintegration and simultaneous activation of isotope families. (orig./MG)

  1. History of radioactivity

    The author describes the historical development of the physics of atoms and nuclei. After a consideration of the ancient Greek philosophy concerning atoms the behaviour of gases is discussed with regards to statistical mechanics. Then the developement of chemistry from alchemy is described. Thereafter the early studies of gas discharges are described with regards to the electronic structure of atoms. In this connection the periodic system of elements is considered. Then the detection of the α-radiation of Uranium by Becquerel and the detections of M. and P. Curie are described. Thereafter the radiactive decay of nuclei is discussed. Then a popular introduction into nuclear structure is given with special regards to artificial radioactivity and nuclear fission. Finally nuclear reactors, the atomic bombs, applications of radionuclides, and problems of radiation protection are described. (HSI)

  2. Environmental radioactivity surveillance programme 1990 - 1993

    During the period 1990-1993, the Radiological Protection Institute of Ireland continued its programme of measuring radioactivity levels in airborne dust, rainwater, total fallout, drinking water supplies and milk. The levels of artificially produced radionuclides continue to be insignificant from a radiological safety point of view

  3. Radioactivity and the French uranium bearing minerals

    This special issue of Regne Mineral journal is entirely devoted to the French uranium mining industry. It comprises 4 parts dealing with: the uranium mining industry in France (history, uranium rush, deposits, geologic setting, prosperity and recession, situation in 1998, ore processing); radioactivity and the uranium and its descendants (discovery, first French uranium bearing ores, discovery of radioactivity, radium and other uranium descendants, radium mines, uranium mines, atoms, elements and isotopes, uranium genesis, uranium decay, isotopes in an uranium ore, spontaneous fission, selective migration of radionuclides, radon in mines and houses, radioactivity units, radioprotection standards, new standards and controversies, natural and artificial radioactivity, hazards linked with the handling and collecting of uranium ores, conformability with radioprotection standards, radioactivity of natural uranium minerals); the French uranium bearing minerals (composition, crystal structure, reference, etymology, fluorescence). (J.S.)

  4. Artificial cold exposure induced stroke in renovascular hypertensive rats and its association with cold-inducible RNA binding protein mRNA expression in brain tissue and blood pressure

    2007-01-01

    BACKGROUND: High incidence of stroke at interchange period of autumn and winter was demonstrated by epidemiological survey, and the specific causes should be further investigated.OBJECTIVE: To investigate the influence of artificial cold exposure on the incidence of stroke in renovascular hypertensive rats (RHR), and analyze the association with blood pressure and cold-inducible RNA binding protein (CIRP) mRNA expression in brain tissue.DESIGN: A completely randomized grouping design, a randomized control animal trial.SETTINGS: Lab of Neurology, the First Affiliated Hospital of Sun Yat-sen University; Department of Chemistry, Open laboratory of Chemical Biology, Institute of Molecular Technology for Drug Discovery and Synthesis, University of Hong Kong.MATERIALS: Male SD rats (n =460), weighing 80- 100 g were obtained from Guangdong Province Health Animal Unit. A modified RXZ-300A intelligent artificial climate cabinet (Ningbo Jiangnan Instrument Co.,Ltd., China).METHODS: The experiment were processed in the Lab of Neurology, the First Affiliated Hospital of Sun Yat-sen University and the Open Laboratory of Chemical Biology, Institute of Molecular Technology for Drug Discovery and Synthesis, University of Hong Kong from October 2004 to November 2005. Rats (n =400) were operated to establish 2-kidney 2-clip RHR model as described previously. The sham-operated rats (n =60) served as normotensive controls. Eight weeks later, 300 of RHR were randomly selected according to their systolic blood pressure (SBP) and divided into 3 sub-groups (n =100 per group): mild hypertensive group (SBP of 160 - 200 mm Hg), moderate hypertensive group (SBP of 200 - 220 mm Hg) and severe hypertensive group (SBP > 220 mm Hg). Each group was further divided into two groups (n =50) under ACE and non-ACE. Normal sham-operated SD rats (n =60), SBP < 140 mm Hg, were randomly divided into two groups: Sham-operated control group (n =30) under ACE and non-ACE. To establish the ACE and non

  5. Determination of the fission barrier height in fission of heavy radioactive beams induced by the (d,p)-transfer

    A theoretical framework is described, allowing to determine the fission barrier height using the observed cross sections of fission induced by the (d,p)-transfer with accuracy, which is not achievable in another type of low-energy fission of neutron-deficient nuclei, the $\\beta$-delayed fission. The proposed experiment [1] at the HIE-ISOLDE, using the ACTAR TPC, will thus provide the experimental information, which is not available at the moment and which is highly interesting for nuclear theory.

  6. Radioactivity Monitoring of the Irish Environment 2006

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) in 2006. This programme aims to assess the exposure of the Irish population to artificial radioactivity in the environment, to review the temporal and geographical distribution of contaminating radionuclides and to maintain systems and procedures which would allow a rapid assessment of environmental contamination to be made in the event of a radiological emergency. Radioactivity is present in the environment due to natural processes, the testing of nuclear weapons in the atmosphere, past nuclear accidents such as that at Chernobyl in Ukraine and the routine discharge of radionuclides from nuclear installations. Liquid discharges from the British Nuclear Group reprocessing plant at Sellafield in Cumbria in the north-west of England, which are licensed by the UK Environment Agency, continue to be the dominant source of artificial radioactivity in the Irish marine environment. The key elements of the monitoring programme implemented by the RPII in 2006 included; assessment of ambient radioactivity based on measurements of radioactivity in air and of external gamma dose rate at permanent monitoring stations located throughout the country; assessment of levels of radioactivity in drinking water; assessment of levels of radioactivity in foodstuffs based on measurements of total diet, milk and various ingredients; assessment of levels of radioactivity in the Irish marine environment based on sampling and measurement of seawater, sediment, seaweed, fish and shellfish. The RPII monitored airborne radioactivity at ten stations located throughout the country. One of these stations is equipped with a high volume sampler, which allows concentrations of caesium-137 to be measured; another is equipped to detect the presence of the gas krypton-85. This gas is released into the environment primarily as a result of the

  7. Comparative observation of primiparae undergone drug-induced abortion or artificial abortion on subsequent pregnancy%初产妇药物流产与人工流产术后对再妊娠影响的对比观察

    丘东海; 叶娉婷

    2013-01-01

    目的:比较初产妇药物流产后和人工流产术后对再妊娠的影响,为选择合适、安全的流产方式提供临床参考.方法:采用回顾性调查方法对135例有人工流产术史、126例有药物流产史及130例无流产史的初产妇进行比较,观察其妊娠期和分娩期并发症的发生情况以及妊娠结局.结果:妊娠期人流组先兆流产发生率明显高于药流组和无流产组,差异有统计学意义(χ2=14.993,P0.05).分娩期人流组产后出血、胎盘粘连和胎盘残留的发生率明显高于药流组和无流产组,χ2分别为22.146、12.211、9.387,P值均0.05).结论:初产妇药物流产后对再次妊娠影响小于人工流产术后,可考虑作为临床终止早孕的首先选择.%Objective :To observe the efforts of drug-induced aboition or aitifirial aboition for primiparous women on their subsequent pregnancies for cliniral evidence to determine a safe and adequate means for termination of pregnancy. Methods: Retrospective comparative study was performed in 135 primiparae undergone artificial aboition, 126 with drug-induced aboition history and 130 primiparity without aboition to examine outcomes of subsequent pregnancy and complications associated with gestation and delivery. Results : Higher incidence of threatened aboition during the gestation period was found in women undergone artificial aboition as compared with those with drug-induced aboition or without aboition history. The difference was significant ( x2 = 14. 993 , P 0. 05 ). Similarly, Mothers with a history of artificial aboition had significantly higher incidence of postpaitum hemorrhage, placenta! adherence and residual placenta in labor than those experienced drug-induced aboition or no aboition ( x2 - 22. 146, x2 -12.211, x2 - 9. 387 , respectively ,P 0. 05 ). Conclusion-. Ding-induced aboition for prhnigravidas seem to produce less effects on their subsequent pregnancies than artificial intervention, and may be recommended as

  8. Radioactivity monitoring in Ireland of air, deposition and water 1982-1987

    The Nuclear Energy Board in conjunction with the Meteorological Service undertakes an environmental radioactivity monitoring programme with the objective of determining levels of artificially produced radioactivity in the Irish environment. The levels of radioactivity in airbourne dust, total fallout samples, precipitation and drinking water are presented for 1982, 1983, 1984, 1985, 1986 and 1987

  9. Novel approaches to the analysis of nuclear and other radioactive materials - Improving detection capability through alpha-gamma coincidence, alpha-induced optical fluorescence and advanced spectrum analysis

    Ihantola, Sakari

    2013-01-01

    Nuclear and other radioactive materials pose a special concern in the proliferation of nuclear weapons, reactor accidents or through criminal acts. To prevent the adverse effects of the use of these materials, novel approaches for their detection and analysis are required. The objective of the research in this thesis was to improve the detection and characterisation of nuclear and other radioactive materials with radiometric methods. Radioactive sources can be detected and identified base...

  10. Wear measurement using radioactive tracer technique based on proton, deuteron and α-particle induced nuclear reactions on molybdenum

    Highlights: ► Proton, deuteron, 3He and α-particle activation of Mo. ► TLA (thin layer activation). ► Wear measurement. ► Integral production yields. ► Wear curves (specific activity versus penetration depth). - Abstract: Excitation functions of light ion induced nuclear reactions on natural molybdenum have been studied in the frame of a systematic investigation of charged particle induced nuclear reactions on metals for various applications. Excitation functions of 93,94g,94m,95g,95m,96,99mTc, 90,93m,99Mo, 90,91m,92m,95m,95g,96Nb and 88,89Zr were measured up to 50 MeV deuteron energy Tárkányi et al., 2012 [1], 93m,93g,94m,94g,95m,95g,96g,99mTc, 90,93m,99Mo, 90,92m,95m,95g,96Nb and 88,89Zr were measured up to 40 MeV proton energy Tárkányi et al., 2012 [2] and 93m,93g,94m,94g,95m,95g,96g,99mTc, 93m,99Mo, 90Nb, 94,95,97,103Ru and 88Zr were measured up to 40 MeV alpha energy Ditrói et al., 2012 [3] by using the stacked foil technique and activation method. The results for 3He induced reactions on natural Mo were taken from the literature Comparetto and Qaim, 1980 [4]. According to their half-lives, from the above listed radionuclides the 95m,96Tc, 91m,92m,95m,95gNb, 99Mo, 103,97Ru and 88Zr are suitable candidates for wear measurement by using thin layer activation (TLA) method. The goal of this work was to determine the necessary nuclear data for TLA of the above radionuclides and to prove their applicability for wear measurements.

  11. Radioactive waste management

    This eighth chapter presents the radioactive wastes and waste disposal; classification of radioactive wastes; basis requests of the radioactive waste management; conditions for a radioactive waste disposal; registers and inventories; transport of radioactive wastes from a facility to another and the radioactive waste management plan

  12. Radioactive waste

    Focusing on radioactive waste management and disposal policies in the United Kingdom, Sweden and the Federal Republic of Germany, this book gives a detailed historical account of the policy process in these three countries, and draws out the implications for theory and public policy. This comparative approach underlines how profoundly different the policy process has been in different countries. By comparing the evolution of policy in three countries, fundamental questions about the formation and resolution of technical decisions under uncertainty are clarified. The analysis of nuclear strategy, the politics of nuclear power, and the shifting emphasis of government regulation redefines the issue of radwaste management and sets it at the heat of the current debate about power, the environment and society. The combination of up-to-date technological assessment with an account of the social and political implications of radwaste management makes'Radioactive Waste'particularly useful to students of environmental studies, geography and public administration. (author)

  13. Radioactive alchemy

    Anon.

    2014-07-15

    For any entity involved in radioactive waste management, turning lead into gold means succeeding with minimising the volumes and optimizing the long-term containment of ultimate waste to be disposed of. With this purpose, they perform R and D on different sorting, treatment and disposal technology, as explained by Frederic Plas from Andra (France), Jan Deckers from Belgoprocess (Belgium) and Wilhelm Bollingerfehr from DBE Technology (Germany). (orig.)

  14. Radioactive alchemy

    For any entity involved in radioactive waste management, turning lead into gold means succeeding with minimising the volumes and optimizing the long-term containment of ultimate waste to be disposed of. With this purpose, they perform R and D on different sorting, treatment and disposal technology, as explained by Frederic Plas from Andra (France), Jan Deckers from Belgoprocess (Belgium) and Wilhelm Bollingerfehr from DBE Technology (Germany). (orig.)

  15. Capillary electrophoresis with laser-induced fluorescent detection method using highly emissive probes for analysis of actinides in radioactive wastes - 59092

    Actinides are important nuclides for the analysis of radioactive wastes arising from nuclear fuel cycle facilities. In order to achieve simple and rapid analysis of actinides, capillary electrophoresis-laser-induced fluorescent detection method (CE-LIF) is one of the potential candidates. In this study, new emissive probes of actinide ions suitable for CE-LIF were developed for the first time. The detection and separation of americium and neptunium ions as model nuclides were examined using several new emissive complexing probes, each of which possessed a fluoro-phore and a different chelating moiety. With a pre-capillary complexation technique without addition of the probe to separation buffer electrolyte, the highly sensitive fluorescent detection of Am and Np was successfully achieved using acyclic and macrocyclic multi-dentate probes. The results suggests that the probe with an acyclic hexa-dentate chelating moiety is suitable for detection and separation of Am and Np. The detection limit of mid-ppt levels was determined. (authors)

  16. Application of a series of artificial neural networks to on-site quantitative analysis of lead into real soil samples by laser induced breakdown spectroscopy

    El Haddad, J. [Univ. Bordeaux, LOMA, CNRS UMR 5798, F-33400 Talence (France); Bruyère, D. [BRGM, Service Métrologie, Monitoring et Analyse, 3 av. C. Guillemin, B.P 36009, 45060 Orléans Cedex (France); Ismaël, A.; Gallou, G. [IVEA Solution, Centre Scientifique d' Orsay, Bât 503, 91400 Orsay (France); Laperche, V.; Michel, K. [BRGM, Service Métrologie, Monitoring et Analyse, 3 av. C. Guillemin, B.P 36009, 45060 Orléans Cedex (France); Canioni, L. [Univ. Bordeaux, LOMA, CNRS UMR 5798, F-33400 Talence (France); Bousquet, B., E-mail: bruno.bousquet@u-bordeaux.fr [Univ. Bordeaux, LOMA, CNRS UMR 5798, F-33400 Talence (France)

    2014-07-01

    Artificial neural networks were applied to process data from on-site LIBS analysis of soil samples. A first artificial neural network allowed retrieving the relative amounts of silicate, calcareous and ores matrices into soils. As a consequence, each soil sample was correctly located inside the ternary diagram characterized by these three matrices, as verified by ICP-AES. Then a series of artificial neural networks were applied to quantify lead into soil samples. More precisely, two models were designed for classification purpose according to both the type of matrix and the range of lead concentrations. Then, three quantitative models were locally applied to three data subsets. This complete approach allowed reaching a relative error of prediction close to 20%, considered as satisfying in the case of on-site analysis. - Highlights: • Application of a series of artificial neural networks (ANN) to quantitative LIBS • Matrix-based classification of the soil samples by ANN • Concentration-based classification of the soil samples by ANN • Series of quantitative ANN models dedicated to the analysis of data subsets • Relative error of prediction lower than 20% for LIBS analysis of soil samples.

  17. Application of a series of artificial neural networks to on-site quantitative analysis of lead into real soil samples by laser induced breakdown spectroscopy

    Artificial neural networks were applied to process data from on-site LIBS analysis of soil samples. A first artificial neural network allowed retrieving the relative amounts of silicate, calcareous and ores matrices into soils. As a consequence, each soil sample was correctly located inside the ternary diagram characterized by these three matrices, as verified by ICP-AES. Then a series of artificial neural networks were applied to quantify lead into soil samples. More precisely, two models were designed for classification purpose according to both the type of matrix and the range of lead concentrations. Then, three quantitative models were locally applied to three data subsets. This complete approach allowed reaching a relative error of prediction close to 20%, considered as satisfying in the case of on-site analysis. - Highlights: • Application of a series of artificial neural networks (ANN) to quantitative LIBS • Matrix-based classification of the soil samples by ANN • Concentration-based classification of the soil samples by ANN • Series of quantitative ANN models dedicated to the analysis of data subsets • Relative error of prediction lower than 20% for LIBS analysis of soil samples

  18. Radioactivity Monitoring of the Irish Environment 2007

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) in 2007. This programme aims to assess the exposure of the Irish population to artificial radioactivity in the envorinment, to review the temporal and geographical distribution of contaminating radionuclides and to maintain systems and procedures which would allow a rapid assessment of environmental contamination to be made in the event of a radiological emergency. In additiopn, some natural radioactivity exposure pathways are included in the programme including radioactivity in surface and ground drinking water. Radioactivity is present in the environment due to natural oprocesses, the testing of nuclear weapons in the atmosphere, past nuclear accidents such as that at Chernobyl in the Ukraine and the routine discharge of radionuclides from nuclear installations. Liquid discharges from the British Nuclear Group reprocessing plant at Sellafield in Cumbria in the north-west of England continue to be the dominant source of artificial radioactivity in the Irish marine environment. The key elements of the monitoring programme implemented by the RPII in 2007 included; assessment of ambient radioactivity based on measurements of radioactivity in air and of external gamma dose rate at permanent monitoring stations located throughout the country; assessment of levels of radioactivity in drinking water; assessment of levels of radioactivity in foodstuffs based on measurements of total diet, milk and various ingredients; assessment of levels of radioactivity in the Irish marine environment based on sampling and measurement of seawater, sediment, seaweed, fish and shellfish. The RPII monitored airborne radioactivity at twelve stations located throughout the country. One of these stations is equipped with a high volume sampler, which allows background concentrations of caesium-137 to be measured; another is equipped to

  19. Artificial Inteligence and Law

    Fuková, Kateřina

    2012-01-01

    Submitted diploma work Artificial Intelligence and Law deals with the rule of law and its position in the process of new advanced technologies in computer cybernetics and further scientific disciplines related with artificial intelligence and its creation. The first part of the work introduces the history of the first imagines about artificial intelligence and concerns with its birth. This chapter presents main theoretical knowledge and hypotheses defined artificial intelligence and progre...

  20. Artificial Skin in Robotics

    Strohmayr, Michael

    2012-01-01

    Artificial Skin - A comprehensive interface for system-environment interaction - This thesis investigates a multifunctional artificial skin as touch sensitive whole-body cover for robotic systems. To further the evolution from tactile sensors to an implementable artificial skin a general concept for the design process is derived. A standard test procedure is proposed to evaluate the performance. The artificial skin contributes to a safe and intuitive physical human robot interaction.

  1. Artificial Radiotracer Applications in Aquatic Environments

    The use of artificial radiotracers in the environment is analogous to their use in the human body. In both domains they provide data on flow rates and pathways, on exchange with materials and on their final discharge from the studied system. Artificially injected radiotracers have been used to investigate flow in natural waters since the 1950's. Identification of flow paths, diagnosis of blockages or leakage, measurement of flow rates, dispersion and exchange processes, such as biological uptake or sorption, are all aspects to which a wide range of artificial radioactive tracers have been applied. Increasingly radiotracers are used in combination with numerical modelling to improve confidence in the predictive capacity of models used in the management of our water resources and to extend their spatial applicability. In turn this allows us to use less and less tracer and demonstrate that the human and environmental impact of modern radiotracer studies is minimal. (author)

  2. Radioactive Cs in the estuary sediments near Fukushima Daiichi Nuclear Power Plant.

    Yamasaki, Shinya; Imoto, Junpei; Furuki, Genki; Ochiai, Asumi; Ohnuki, Toshihiko; Sueki, Keisuke; Nanba, Kenji; Ewing, Rodney C; Utsunomiya, Satoshi

    2016-05-01

    The migration and dispersion of radioactive Cs (mainly (134)Cs and (137)Cs) are of critical concern in the area surrounding the Fukushima Daiichi Nuclear Power Plant (FDNPP). Considerable uncertainty remains in understanding the properties and dynamics of radioactive Cs transport by surface water, particularly during rainfall-induced flood events to the ocean. Physical and chemical properties of unique estuary sediments, collected from the Kuma River, 4.0km south of the FDNPP, were quantified in this study. These were deposited after storm events and now occur as dried platy sediments on beach sand. The platy sediments exhibit median particle sizes ranging from 28 to 32μm. There is increasing radioactivity towards the bottom of the layers deposited; approximately 28 and 38Bqg(-1) in the upper and lower layers, respectively. The difference in the radioactivity is attributed to a larger number of particles associated with radioactive Cs in the lower part of the section, suggesting that radioactive Cs in the suspended soils transported by surface water has decreased over time. Sequential chemical extractions showed that ~90% of (137)Cs was strongly bound to the residual fraction in the estuary samples, whereas 60~80% of (137)Cs was bound to clays in the six paddy soils. This high concentration in the residual fraction facilitates ease of transport of clay and silt size particles through the river system. Estuary sediments consist of particles <100μm. Radioactive Cs desorption experiments using the estuary samples in artificial seawater revealed that 3.4±0.6% of (137)Cs was desorbed within 8h. More than 96% of (137)Cs remained strongly bound to clays. Hence, particle size is a key factor that determines the travel time and distance during the dispersion of (137)Cs in the ocean. PMID:26874771

  3. High energy muon induced radioactive nuclides in nickel plate and its use for 2-D muon-beam image profile

    Kurebayashi, Y.; Sakurai, H.; Takahashi, Y.; Doshita, N.; Kikuchi, S.; Tokanai, F.; Horiuchi, K.; Tajima, Y.; Oe, T.; Sato, T.; Gunji, S.; Inui, E.; Kondo, K.; Iwata, N.; Sasaki, N.; Matsuzaki, H.; Kunieda, S.

    2015-11-01

    Target materials were exposed to a muon beam with an energy of 160 GeV/c at the COMPASS experiment line in CERN-SPS to measure the production cross-sections for muon-induced radionuclides. A muon imager containing four nickel plates, each measuring 100 mm×100 mm, exposed to the IP plate successfully detected the muon beam image during an irradiation period of 33 days. The contrasting density rate of the nickel plate was (5.2±0.7)×10-9 PSL/muon per one-day exposure to IP. The image measured 122 mm and 174 mm in horizontal and vertical lengths, respectively, in relation to the surface of the base, indicating that 50±6% of the muon beam flux is confined to an area of 18% of the whole muon beam. The number of muons estimated from the PSL value in the total beam image area (0.81±0.1)×1013 was comparable to the total muon counts of the ion-chamber at the M2 beam line in the CERN-SPS. The production cross-sections of Cr-51, Mn-54, Co-56, Co-57, and Co-58 in nickel were 0.19±0.08, 0.34±0.06, 0.5±0.05, 3.44±0.07, 0.4±0.03 in the unit of mb, respectively, reducing muon associated particles effects. They are approximately 10 times smaller than that a proceeding study by Heisinger et al.

  4. High energy muon induced radioactive nuclides in nickel plate and its use for 2-D muon-beam image profile

    Kurebayashi, Y. [Graduate School of Science and Engineering, Yamagata University, Yamagata 990-8560 (Japan); Sakurai, H., E-mail: sakurail@sci.kj.yamagata-u.ac.jp [Department of Physics, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Takahashi, Y. [Graduate School of Science and Engineering, Yamagata University, Yamagata 990-8560 (Japan); Doshita, N. [Department of Physics, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Kikuchi, S. [Graduate School of Science and Engineering, Yamagata University, Yamagata 990-8560 (Japan); Tokanai, F. [Department of Physics, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Horiuchi, K. [Graduate School of Science and Technology, Hirosaki University, 3, Bunkyo-chou, Hirosaki 036-8561, Aomori (Japan); Tajima, Y. [Institute of Arts and Sciences, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Oe, T. [Department of Physics, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Sato, T. [Graduate School of Science and Engineering, Yamagata University, Yamagata 990-8560 (Japan); Gunji, S. [Department of Physics, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Inui, E. [Faculty of Science, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Kondo, K. [Department of Physics, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Iwata, N. [Dept. of Earth and Environmental Science, Yamagata University, 1-4-12 Kojirakawa, Yamagata 990-8560 (Japan); Sasaki, N. [Graduate School of Science and Technology, Hirosaki University, 3, Bunkyo-chou, Hirosaki 036-8561, Aomori (Japan); Matsuzaki, H. [Micro Analysis Laboratory, Tandem accelerator (MALT), The University Museum, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Kunieda, S. [Nuclear Data Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun 319-1195, Ibaraki (Japan)

    2015-11-01

    Target materials were exposed to a muon beam with an energy of 160 GeV/c at the COMPASS experiment line in CERN-SPS to measure the production cross-sections for muon-induced radionuclides. A muon imager containing four nickel plates, each measuring 100 mm×100 mm, exposed to the IP plate successfully detected the muon beam image during an irradiation period of 33 days. The contrasting density rate of the nickel plate was (5.2±0.7)×10{sup –9} PSL/muon per one-day exposure to IP. The image measured 122 mm and 174 mm in horizontal and vertical lengths, respectively, in relation to the surface of the base, indicating that 50±6% of the muon beam flux is confined to an area of 18% of the whole muon beam. The number of muons estimated from the PSL value in the total beam image area (0.81±0.1)×10{sup 13} was comparable to the total muon counts of the ion-chamber at the M2 beam line in the CERN-SPS. The production cross-sections of Cr-51, Mn-54, Co-56, Co-57, and Co-58 in nickel were 0.19±0.08, 0.34±0.06, 0.5±0.05, 3.44±0.07, 0.4±0.03 in the unit of mb, respectively, reducing muon associated particles effects. They are approximately 10 times smaller than that a proceeding study by Heisinger et al.

  5. The natural radioactivity of the biosphere

    Of the approximately 1200 isotopes presently known more than 900 are radioactive. The nuclei of these isotopes are unstable and decay spontaneously emitting ionizing gamma-, alpha- or beta-radiation. The overwhelming majority of known radioactive isotopes have been obtained artificially; only a few are natural. Numerous investigations have shown that many of the natural radioactive isotopes can be grouped into three radioactive families. Each such family is characterized by the existence of one long-lived isotope - the family parent, one gaseous isotope of radon, intermediate radioactive decay products and final stable isotopes of atomic weights 206, 207 and 208. No such generic relationship has been established among the remaining natural radioactive isotopes. The purpose of the book, in contrast to some recent review works, is to present, in addition to a summary of reference data characterizing the radioactivity levels of various components of the biosphere, a description of those phenomena and regularities which will apparently make it possible to understand more completely the basic dynamics of the natural radioactivity of the biosphere and, consequently, contribute to a more correct interpretation of radiation-hygiene in each specific case

  6. Radioactivity Monitoring of the Irish Environment 2009

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) during 2009. The RPII has routinely monitored levels of radioactivity in the environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually so as to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The principal aims of the RPII's monitoring programme are; to assess the level of radioactivity to which the Irish population is exposed as a result of radioactivity in the environment; to study trends and establish the geographical distribution of contaminating radionuclides so as to better understand the long term behaviour of artificial radioactivity in the food chain and the environment; to ensure that any increase in radiation levels resulting from an accidental release of radioactivity to the environment is detected and assessed rapidly. During 2009 radioactivity was measured in a wide range of foods and environmental materials including: air, water, milk, seafood, foodstuffs and complete meals. The most significant source of artificial radioactivity in the Irish marine environment is the discharge of low level liquid radioactive waste from the Sellafield Nuclear Fuel Reprocessing Plant on the north east coast of England. In order to assess the exposure arising from the source extensive sampling of fish and shellfish landed at ports along the north east coast of Ireland is undertaken. The most exposed group of individuals to discharges from Sellafield have been identified as commercial oyster and mussel farmers working along the north east coastline and their families. Manmade radioactivity is also present in the terrestrial environment due primarily to residual global fallout arising primarily from atmospheric testing of nuclear

  7. Radioactivity Monitoring of the Irish Environment 2008

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) during 2008. The RPII has routinely monitored levels of radioactivity in the environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually so as to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The principal aims of the RPII's monitoring programme are; to assess the level of radioactivity to which the Irish population is exposed as a result of radioactivity in the environment; to study trends and establish the geographical distribution of contaminating radionuclides so as to better understand the long term behaviour of artificial radioactivity in the food chain and the environment; to ensure that any increase in radiation levels resulting from an accidental release of radioactivity to the environment is detected and assessed rapidly. During 2008 radioactivity was measured in a wide range of foods and environmental materials including: air, water, milk, seafood, foodstuffs and complete meals. The most significant source of artificial radioactivity in the Irish marine environment is the discharge of low level liquid radioactive waste from the Sellafield Nuclear Fuel Reprocessing Plant on the north east coast of England. In order to assess the exposure arising from the source extensive sampling of fish and shellfish landed at ports along the north east coast of Ireland is undertaken. The most exposed group of individuals to discharges from Sellafield have been identified as commercial oyster and mussel farmers working along the north east coastline and their families. Manmade radioactivity is also present in the terrestrial environment due primarily to residual global fallout arising primarily from atmospheric testing of nuclear

  8. Comparison of cross-sectional hardness and transverse microradiography of artificial carious enamel lesions induced by different demineralising solutions and gels

    Magalhães, A C; Moron, B M; Comar, L P; Wiegand, A.; Buchalla, W.; Buzalaf, M.A.R.

    2009-01-01

    The aims of this study were: (1) to correlate surface (SH) and cross-sectional hardness (CSH) with microradiographic parameters of artificial enamel lesions; (2) to compare lesions prepared by different protocols. Fifty bovine enamel specimens were allocated by stratified randomisation according to their initial SH values to five groups and lesions produced by different methods: MC gel (methylcellulose gel/lactic acid, pH 4.6, 14 days); PA gel (polyacrylic acid/lactic acid/hydroxyapatite, pH ...

  9. Radioactive nuclides in the living environment

    There are several radioactive nuclides in the living environment, such as those existing since the creation of the earth, those coming from experimental nuclear explosions, and radiations of the cosmic rays. A lesson on these radioactive nuclides was considered useful for understanding the place of nuclear technology, and have been made on the title of 'Radioactive Nuclides in the Living Environment' in the general course of the Nuclear Engineering School of Japan Atomic Energy Research Institute. When the curriculum of the general course was modified in 1993, the lesson was left in a changed form. Thus, the textbook of the lesson is presented in this report. The contents are natural and artificial radioactive nuclides in the living environment and where they have come from etc. (author)

  10. Radioactive wastes

    Here are gathered 1)the decrees (99-686 and 99-687) of the 3 rd of August 1999 relative to the researches on radioactive waste management. A local committee of information and follow-up has to be established on the site of each underground facility. The composition of this committee is determined here (99-686). 3 people will from now on be jointly ordered by the Minister of Economy, Finance and Industry and by the Secretary of State of Industry to conduct a preliminary dialogue for the choice of one or several sites on which previous works should be made before the construction of an underground facility (99-687). They take the opinion of the people's representatives, the associations and the concerned population and inform the Ministers of Environment, Energy and Research of the collected information. 2)the decree of the 3 rd of August 1999 authorizing the 'Agence nationale pour la gestion des dechets radioactifs' (ANDRA) to install and exploit an underground facility located in Bure (Meuse) and intended to study the deep geological deposits where could be stored radioactive wastes. (O.M.)

  11. Molecular recognition and organizational and polyvalent effects in vesicles induce the formation of artificial multicompartment cells as model systems of eukaryotes.

    Paleos, Constantinos M; Pantos, A

    2014-05-20

    Researchers have become increasingly interested in the preparation and characterization of artificial cells based on amphiphilic molecules. In particular, artificial cells with multiple compartments are primitive mimics of the structure of eukaryotic cells. Endosymbiotic theory, widely accepted among biologists, states that eukaryotic cells arose from the assembly of prokaryotic cells inside other cells. Therefore, replicating this process in a synthetic system could allow researchers to model molecular and supramolecular processes that occur in living cells, shed light on mass and energy transport through cell membranes, and provide a unique, isolated space for conducting chemical reactions. In addition, such structures can serve as drug delivery systems that encapsulate both bioactive and nonbiocompatible compounds. In this Account, we present various coating, incubation, and electrofusion strategies for forming multicompartment vesicle systems, and we are focusing on strategies that rely on involving molecular recognition of complementary vesicles. All these methods afforded multicompartment systems with similar structures, and these nanoparticles have potential applications as drug delivery systems or nanoreactors for conducting diverse reactions. The complementarity of interacting vesicles allows these artificial cells to form, and the organization and polyvalency of these interacting vesicles further promote their formation. The incorporation of cholesterol in the bilayer membrane and the introduction of PEG chains at the surface of the interacting vesicles also support the structure of these multicompartment systems. PEG chains appear to destabilize the bilayers, which facilitates the fusion and transport of the small vesicles to the larger ones. Potential applications of these well-structured and reproducibly produced multicompartment systems include drug delivery, where researchers could load a cocktail of drugs within the encapsulated vesicles, a process

  12. Gas and water flow in an excavation-induced fracture network around an underground drift: A case study for a radioactive waste repository in clay rock

    de La Vaissière, Rémi; Armand, Gilles; Talandier, Jean

    2015-02-01

    The Excavation Damaged Zone (EDZ) surrounding a drift, and in particular its evolution, is being studied for the performance assessment of a radioactive waste underground repository. A specific experiment (called CDZ) was designed and implemented in the Meuse/Haute-Marne Underground Research Laboratory (URL) in France to investigate the EDZ. This experiment is dedicated to study the evolution of the EDZ hydrogeological properties (conductivity and specific storage) of the Callovo-Oxfordian claystone under mechanical compression and artificial hydration. Firstly, a loading cycle applied on a drift wall was performed to simulate the compression effect from bentonite swelling in a repository drift (bentonite is a clay material to be used to seal drifts and shafts for repository closure purpose). Gas tests (permeability tests with nitrogen and tracer tests with helium) were conducted during the first phase of the experiment. The results showed that the fracture network within the EDZ was initially interconnected and opened for gas flow (particularly along the drift) and then progressively closed with the increasing mechanical stress applied on the drift wall. Moreover, the evolution of the EDZ after unloading indicated a self-sealing process. Secondly, the remaining fracture network was resaturated to demonstrate the ability to self-seal of the COx claystone without mechanical loading by conducting from 11 to 15 repetitive hydraulic tests with monitoring of the hydraulic parameters. During this hydration process, the EDZ effective transmissivity dropped due to the swelling of the clay materials near the fracture network. The hydraulic conductivity evolution was relatively fast during the first few days. Low conductivities ranging at 10-10 m/s were observed after four months. Conversely, the specific storage showed an erratic evolution during the first phase of hydration (up to 60 days). Some uncertainty remains on this parameter due to volumetric strain during the

  13. Uranium and radioactivity

    The article gives results of investigations on uranium content and the proportion of induced and natural radioactivity in wines of different vines and regions. The ecological chain of ground, vine, grape, grape-juice, and wine is described, and the author shows that 14C and T measurements can be used to determine the age of wines with the aim of detecting adulterated vintages and blends of different years. The 14C and T content also indicates a direct connection with nuclear explosions. (RB/AK)

  14. Chemical and isotopic characterization of water-rock interactions in shales induced by the intrusion of a basaltic dike: A natural analogue for radioactive waste disposal

    Disposal of nuclear waste in deep geological formations is expected to induce thermal fluxes for hundreds of years with maximum temperature reaching about 100-150 deg. C in the nearfield argillaceous environment. The long-term behavior of clays subjected to such thermal gradients needs to be perfectly understood in safety assessment considerations. In this respect, a Toarcian argillaceous unit thermally disturbed by the intrusion of a 1.1-m wide basaltic dike at the Perthus pass (Herault, France), was studied in detail as a natural analogue. The thermal imprint induced by the dike was evaluated by a mineralogical, chemical and K-Ar study of the <2 μm clay fraction of shale samples collected at increasing distance from the basalt. The data suggest that the mineral composition of the shales was not significantly disturbed when the temperature was below 100-150 deg. C. Closer to the dike at 150-300 deg. C, changes such as progressive dissolution of chlorite and kaolinite, increased content of the mixed layers illite-smectite with more illite layers, complete decalcification and subsequent increased content of quartz, were found. At the eastern contact with the dike, the mineral and chemical compositions of both the shales and the basalt suggest water-rock interactions subsequent to the intrusion with precipitation of palagonite and renewed but discrete deposition of carbonate. A pencil cleavage developed in the shales during the dike emplacement probably favored water circulation along the contact. Strontium isotopic data suggest that the fluids of probable meteoric origin, reacted with Bathonian and Bajocian limestones before entering the underlying Toarcian shales. By analogy with deep geological radioactive waste repositories, the results report discrete mineralogical variations of the clays when subjected to temperatures of 100-150 deg. C that are expected in deep storage conditions. Beyond 150 deg. C, significant mineralogical changes may alter the physical and

  15. On the formation of non-radioactive copper during the production of 64Cu via proton and deuteron-induced nuclear reactions on enriched 64Ni targets

    Routine production of 64Cu commonly exploits the 64Ni(p,n) or 64Ni(d,2n) reactions. Above specific threshold energies, however, non-radioactive 63Cu and/or 65Cu are also co-produced. The non-radioactive (cold) Cu can significantly decrease the specific activity (SA) of 64Cu-labelled radiopharmaceuticals. Based on nuclear model calculations for the formation of non-radioactive Cu isotopes, theoretical specific activities (TSA) for 64Cu were estimated. Reported current production methods, however, often yield SA values that are lower than the corresponding TSA predictions by more than an order of magnitude. Most of the non-radioactive Cu causing this has been found to originate from sources other than co-production, indicating that there is still significant potential for method improvement. (author)

  16. Environmental radioactivity

    The evaluation of more than 50 official points of measurement for the control of environmental radioactivity in the German Federal Republic showed a marked decrease of activity concentration in the surveyed fields of precipitation, air, water, milk, and humans as compared to 1972. This decrease can be attributed to the stop of above-ground nuclear weapons tests effected in 1963. In 1973, a survey of the environment of nuclear power stations again did not show any significant difference between these regions and others. The mean genetic radiation exposure in the year 1973 is given in a chart. Selected data from different places of measurement give mean values and annual balances of the radionuclides 137Cs and 90Sr for men, women, and children, as well as for cistern water, milk, and hospital food. Finally, a balance of the import and export of radionuclides in 1973 is given. (ORU/AK)

  17. Radioactive colloids

    Different techniques for the characterization of radioactive colloids, used in nuclear medicine, have been evaluated and compared. Several radioactive colloids have been characterized in vitro and in vivo and tested experimentally. Colloid biokinetics following interstitial or intravenous injection were evaluated with a scintillation camera technique. Lymphoscintigraphy with a Tc-99-labelled antimony sulphur colloid was performed in 32 patients with malignant melanoma in order to evaluate the technique. Based on the biokinetic results, absorbed doses in tissues and organs were calculated. The function of the reticuloendothelial system has been evaluated in rats after inoculation with tumour cells. Microfiltration and photon correlation spectroscopy were found to be suitable in determining activity-size and particle size distributions, respectively. Maximal lymph node uptake following subcutaneous injection was found to correspond to a colloid particle size between 10 and 50 nm. Lymphoscintigraphy was found to be useful in the study of lymphatic drainage from the primary tumour site in patients with malignant melanoma on the trunk. Quantitative analysis of ilio-inguinal lymph node uptake in patients with malignant melanoma on the lower extremities was, however, found to be of no value for the detection of metastatic disease in lymph nodes. High absorbed doses may be received in lymph nodes (up to 1 mGy/MBq) and at the injection site (about 10 mGy/MBq). In an experimental study it was found that the relative colloid uptake in bone marrow and spleen depended on the total number of intravenously injected particles. This may considerably affect the absorbed dose in these organs. (author)

  18. Quo Vadis, Artificial Intelligence?

    Alfons Schuster; Daniel Berrar; Naoyuki Sato

    2010-01-01

    Since its conception in the mid 1950s, artificial intelligence with its great ambition to understand and emulate intelligence in natural and artificial environments alike is now a truly multidisciplinary field that reaches out and is inspired by a great diversity of other fields. Rapid advances in research and technology in various fields have created environments into which artificial intelligence could embed itself naturally and comfortably. Neuroscience with its desire to understand nervou...

  19. Anticipatory Artificial Autopoiesis

    DuBois, Daniel; Holmberg, Stig C.

    2010-01-01

    In examining relationships between autopoiesis and anticipation in artificial life (Alife) systems it is demonstrated that anticipation may increase efficiency and viability in artificial autopoietic living systems. This paper, firstly, gives a review of the Varela et al [1974] automata algorithm of an autopoietic living cell. Some problems in this algorithm must be corrected. Secondly, a new and original anticipatory artificial autopoiesis algorithm for automata is presented. ...

  20. Artificial cognition architectures

    Crowder, James A; Friess, Shelli A

    2013-01-01

    The goal of this book is to establish the foundation, principles, theory, and concepts that are the backbone of real, autonomous Artificial Intelligence. Presented here are some basic human intelligence concepts framed for Artificial Intelligence systems. These include concepts like Metacognition and Metamemory, along with architectural constructs for Artificial Intelligence versions of human brain functions like the prefrontal cortex. Also presented are possible hardware and software architectures that lend themselves to learning, reasoning, and self-evolution

  1. Doped Colloidal Artificial Ice

    Libal, A.; Reichhardt, C. J. Olson; Reichhardt, C.

    2015-01-01

    We examine square and kagome artificial spin ice for colloids confined in arrays of double-well traps. Unlike magnetic artificial spin ices, colloidal and vortex artificial spin ice realizations allow creation of doping sites through double occupation of individual traps. We find that doping square and kagome ice geometries produces opposite effects. For square ice, doping creates local excitations in the ground state configuration that produce a local melting effect as the temperature is rai...

  2. Inteligencia artificial en vehiculo

    Amador Díaz, Pedro

    2012-01-01

    Desarrollo de un robot seguidor de líneas, en el que se implementan diversas soluciones de las áreas de sistemas embebidos e inteligencia artificial. Desenvolupament d'un robot seguidor de línies, en el qual s'implementen diverses solucions de les àrees de sistemes encastats i intel·ligència artificial. Follower robot development of lines, in which various solutions are implemented in the areas of artificial intelligence embedded systems.

  3. Artificial life and life artificialization in Tron

    Carolina Dantas Figueiredo

    2012-12-01

    Full Text Available Cinema constantly shows the struggle between the men and artificial intelligences. Fiction, and more specifically fiction films, lends itself to explore possibilities asking “what if?”. “What if”, in this case, is related to the eventual rebellion of artificial intelligences, theme explored in the movies Tron (1982 and Tron Legacy (2010 trat portray the conflict between programs and users. The present paper examines these films, observing particularly the possibility programs empowering. Finally, is briefly mentioned the concept of cyborg as a possibility of response to human concerns.

  4. Radioactive decontamination

    It discusses radioactive decontamination from the practical point of view with aim of contributions to safety control of radioisotopes. As general knowledges, contamination forms are explained from physical states of solid materials' surfaces and classification of contaminative mechanism are conducted in each contamination form. Furthermore, the decontaminants selcted for each classified contaminative mechanism are indicated from pH-effect and concentration effect. Decontamination on laboratory, using wet method generally as a decontamination technic includes irrigation method by decontaminant solution and scrubbing method. Decontamination of machinery and tools includes scrubbing method and the methods using ultrasonic decontamination equipment and semiautomatic decontamination equipment of which flow-diagram is illustrated. The methods of decontamination of clothing include its disposal or the use of tightly-closed full automatic washing machine. The general irrigation method are indicated as decontamination of skin. Furthermore, neutral cleaning material method for elimination of short-term elapsed contamination and Titanium oxide paste method for elimination of long-term elapsed contamination are explained. (Kanao, N.)

  5. A scenario for a genetically controlled fission of artificial vesicles

    Bönzli, Eva; Hadorn, Maik; Jørgensen, Mikkel Girke;

    2011-01-01

    Artificial vesicles have been used for decades as model systems of biological cells to investigate scientific questions in simulacra. In recent years, the significance of artificial vesicles further increased because they represent ideal candidates to become the building block of a de novo constr...... transfer method to prepare vesicles, the base for the development of a protocol to induce fission in artificial cell may be available....

  6. Influence of Artificial Sweetener on Human Blood Glucose Concentration

    Ilse Skokan; P. Christian Endler; Beatrix Wulkersdorfer; Dieter Magometschnigg; Heinz Spranger

    2007-01-01

    Artificial sweeteners, such as saccharin or cyclamic acid are synthetically manufactured sweetenings. Known for their low energetic value they serve especially diabetic and adipose patients as sugar substitutes. It has been hypothesized that the substitution of sugar with artificial sweeteners may induce a decrease of the blood glucose. The aim of this study was to determine the reliability of this hypothesis by comparing the influence of regular table sugar and artificial sweeteners on the b...

  7. Artificial insemination in poultry

    Artificial insemination is a relative simple yet powerful tool geneticists can employ for the propagation of economically important traits in livestock and poultry. In this chapter, we address the fundamental methods of the artificial insemination of poultry, including semen collection, semen evalu...

  8. Occurence of natural and artificial radionuclides in the environment and methods of their detection

    The authors discuss occurence of radionuclides in the environment and illustrate the circulation of natural and artificial radioactive substances in the air, water and soil. Methods are presented of detecting radioactive contamination, including the sampling and detection of radiation emitted by radioactive isotopes contained in the samples. Various conditions as well as the kind of ionizing radiation emitters are taken into consideration. 19 refs. (author)

  9. Environmental radioactivity and radiation exposure

    The environmental radioactivity in the Federal Republic of Germany was almost as high in 1976 as in 1975. It only increased temporarily in autumn 1976 as a result of the above-ground nuclear weapons test of the People's Republic of China on September 29th 1976 and then returned to its previous level. The radioactivity in food had a slight decreasing trend in 1976, apart from a temporary increase in the radioactivity in milk also caused by the nuclear weapons test mentioned. The population exposure remains basically unchanged in 1976 compared with 1975. The artificial radiation exposure is about half as high as the natural radiation exposure to which man has always been exposed. The former is based to 83% on using X-rays in medicine, particularly for X-ray diagnostic purposes. The population exposure due to nuclear power plants and other nuclear plants is still well below 1% of the natural radiation exposure although in 1976 three new nuclear power plants were put into operation. This is also true for the average radiation exposure within an area of 3 km around the nuclear plant. (orig.)

  10. Transport of radioactive substances

    The report on the transport of radioactive substances covers the following topics: facts on radioactive materials transport, safety of the transport of radioactive substances, legal regulations and guidelines: a multiform but consistent system, transport of nuclear fuels, safety during the transport of nuclear fuel, future transport of spent fuel elements and high-level radioactive wastes in Germany.

  11. An Assessment of Radioactivity of Selected Industrial Waste

    phosphogypsum (phph) is a by-product in the manufacture of phosphoric acid for the artificial fertilizer industry. In the present work, qualitative and quantitative radioactive analysis are carried for phph of National Company of Abuzabal for chemical fertilizers. Gamma ray spectroscopy techniques are applied. The present study reveals that the radioactivity resulted from these wastes is out of the international standards, and it is strongly not recommended to be used as a construction material or for dwellings

  12. The Ospar convention and its implementation: radioactive substances

    In the final analysis, it appears that the objectives that have been set, either in general or for the year 2020, are to achieve concentrations of artificial radioactive substances in the environment that are close to zero and not to achieve discharge levels that are close to zero. This objective must be met through a programmed reduction of radioactive discharges that takes into account of criteria relating to technical feasibility and radiological impact. (N.C.)

  13. Radioactivity analyses of food and drinking water in China following the Fukushima nuclear accident

    Objective: To summarize the analytical results of radioactivity in the food and drinking water nationwide following the Fukushima nuclear accident, and to evaluate its possible contamination to the public health in China. Methods: According to the national standard methods and IAEA, FDA correlative references,the scheme was established on sampling and measurements in food and drinking water after the breakout of the accident. The quality control was requested on the sampling, analyses and data report. Results: Trace artificial radioactive isotope of 131I was measured in spinach samples on 2 April 2011 in Beijing. Subsequently 131I was found in 10 kinds of growing leaves vegetables (open field)nationwide. The maximum detectable activity of 131I in vegetables was about 3.1 Bq/kg. Since 3 May 2011, the concentration of 131I has been below the detection limits.No artificial radionuclide was detectable in all of milk, drinking water and marine products samples during March to December, 2011. Conclusions: The food and drinking water measurements in China following the Fukushima nuclear accident denoted that the minor amounts of 131I in vegetables might result in very low absorbed dose and induce no impact on human health. The maximum detectable activity of 131I in vegetables was close to that reported in European countries,and much less than that measured in China immediately after the Chernobyl accident in 1986. (authors)

  14. Radiation protection. Radioactivity and health. 3. ed.

    This booklet makes an attempt at elucidating the mutual influence of radioactivity and health in a way which is understandable to the non-expert. The basics of radioactivity are briefly explained by way of introduction, the next item to be described is exposure of man to natural and artificial radiation. Somatic and genetic effects of radiation on man are subsequently discussed. The whole area of radioecology - starting with radioactive discharge from nuclear plants and going on to the determination of man's exposure to radiation - is covered and supplemented by a description of the risks of radiation therapy. All this serves to describe the results of long-term research on questions of the radiobiological risks in an understandable way and provide useful information about this eminently important area. (orig.)

  15. Radioactivity and Nuclear Issues in Science Fiction

    In this work are presented and reviewed science fiction narratives, films and comics that exploit radioactivity and nuclear issues. These topics to some science fiction authors serve as metaphor of evil and holocaust as well as nice instrument for elaborating various manipulations and conspiracy theories. In that context are of special interest science fiction works depicting apocalyptic post-nuclear worlds and societies, such works being closely connected with cyberpunk genre. However, other more technologically optimistic authors nuclear energy and research regarding nuclear technology and radioactivity consider as eligible and inevitable solution for world peace and prosperity Nowadays, public interest and global fears are shifted from radioactivity and nuclear issues to other catastrophic scenarios threatening future of the mankind, these for example being climate changes and global warming, asteroid impact, collapse of information infrastructure, nanotechnology, robotics and artificial intelligence etc. Consequently, these issues are as well increasingly reflected in contemporary science fiction stories.(author)

  16. Artificial ecosystem selection.

    Swenson, W; Wilson, D S; Elias, R

    2000-08-01

    Artificial selection has been practiced for centuries to shape the properties of individual organisms, providing Darwin with a powerful argument for his theory of natural selection. We show that the properties of whole ecosystems can also be shaped by artificial selection procedures. Ecosystems initiated in the laboratory vary phenotypically and a proportion of the variation is heritable, despite the fact that the ecosystems initially are composed of thousands of species and millions of individuals. Artificial ecosystem selection can be used for practical purposes, illustrates an important role for complex interactions in evolution, and challenges a widespread belief that selection is most effective at lower levels of the biological hierarchy. PMID:10890915

  17. Natural and artificial radioactivity in soils of forests

    Levels of 222 Rn, 40 K, 235 U, 226 Ra and 137 Cs were studied in soils of a forest zone located at 3000 m altitude in the central portion of Mexico. the radon concentrations in different soil horizons were determined with solid state nuclear track detectors and the concentrations of 40 K, 235 U, 226 Ra and 137 Cs in soil samples were measured with a gamma spectrometer at low level coupled to a High purity Ge detector. The results indicate differences of a magnitude order in the radon concentrations inside the studied area. The levels of 40 K, 235 U, 226 Ra and 137 Cs are discussed as function of the perturbation grade of the soil and atmospheric pollution. (Author)

  18. Artificial radioactivity of waters of the Mediterranean Sea

    Cs-137 concentration measurements in surface waters of the Mediterranean and Black Seas, obtained in the R/V 'Gorizont' cruise (May - June 1998), are described. The annual Cs-137 inputs to the Mediterranean Sea from the Black Sea since 1959 till 1998 are estimated

  19. Developing Creativity: Artificial Barriers in Artificial Intelligence

    Jennings, Kyle E.

    2010-01-01

    The greatest rhetorical challenge to developers of creative artificial intelligence systems is convincingly arguing that their software is more than just an extension of their own creativity. This paper suggests that “creative autonomy,” which exists when a system not only evaluates creations on its own, but also changes its standards without explicit direction, is a necessary condition for making this argument. Rather than requiring that the system be hermetically sealed to avoid perceptions...

  20. Principles of artificial intelligence

    Nilsson, Nils J

    1980-01-01

    A classic introduction to artificial intelligence intended to bridge the gap between theory and practice, Principles of Artificial Intelligence describes fundamental AI ideas that underlie applications such as natural language processing, automatic programming, robotics, machine vision, automatic theorem proving, and intelligent data retrieval. Rather than focusing on the subject matter of the applications, the book is organized around general computational concepts involving the kinds of data structures used, the types of operations performed on the data structures, and the properties of th

  1. Intelligence: Real or artificial?

    Schlinger, Henry D

    1992-01-01

    Throughout the history of the artificial intelligence movement, researchers have strived to create computers that could simulate general human intelligence. This paper argues that workers in artificial intelligence have failed to achieve this goal because they adopted the wrong model of human behavior and intelligence, namely a cognitive essentialist model with origins in the traditional philosophies of natural intelligence. An analysis of the word “intelligence” suggests that it originally r...

  2. Artificial Personality and Disfluency

    Wester, Mirjam; Aylett, Matthew; Tomalin, Marcus; Dall, Rasmus

    2015-01-01

    The focus of this paper is artificial voices with different personalities. Previous studies have shown links between an individual's use of disfluencies in their speech and their perceived personality. Here, filled pauses (uh and um) and discourse markers (like, you know, I mean) have been included in synthetic speech as a way of creating an artificial voice with different personalities. We discuss the automatic insertion of filled pauses and discourse markers (i.e., fillers) into otherwise f...

  3. The Artificial Anal Sphincter

    Christiansen, John

    2000-01-01

    The artificial anal sphincter as treatment for end stage anal incontinence was first described in 1987. Published series concern a total of 42 patients, with a success rate of approximately 80%. Infection has been the most serious complication, but a number of technical complications related to the device have also occurred and required revisional procedures in 40% to 60% of the patients. The artificial anal sphincter may be used for the same indications as dynamic graciloplasty except in pat...

  4. Survey monitoring of environmental radioactivity in Daejeon area

    Jun, Jae Shik.; Noh, Hyung Ah [Taejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2000-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Taejon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Taejon Radiation Monitoring Station in 2000. In conclusion, the natural environmental radiation level in Taejon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  5. Survey monitoring of environmental radioactivity in Daejeon area

    Jun, Jae Shik; Noh, Hyung Ah [Daejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2003-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2002. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  6. Radioactive characterization of sand samples from Failaka Island in Kuwait

    Sand samples were collected from Failaka Island in the state of Kuwait for radioactive characterization. The activity concentrations of both natural and artificial radionuclides were determined using gamma (γ)-ray spectrometry. From the measured γ-spectra, radioactivity concentrations were determined for Uranium-238 (238U), Thorium-232 (232Th), Radium-226 (226Ra), Potassium-40 (40K), and Cesium-137 (137Cs). To evaluate the radiological hazard of the natural radioactivity on Failaka Island, the radium equivalent activity, the representative level index, the external hazard index, the internal hazard index, the absorbed dose, and the effective dose rate were calculated and compared with international approved values. (author)

  7. Survey monitoring of environmental radioactivity in Daejeon area

    Jun, Jae Sik; Noh, Hyung Ah [Daejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2001-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2001. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  8. Records of Gamma Radiation from the Ground and Beta Radiation from Radioactive Debris in Sweden, 1950–1955. Part I

    Sievert, Rolf M.

    2011-01-01

    The γ radiation of the ground from natural and artificial radioactivity, and the β radiation from radioactive debris in the atmosphere, have been recorded in Sweden since 1950. On several occasions increased radioactivity has been observed, sometimes producing effects by far exceeding the variations of the normal level. Observations are reported on the influence of rain and snowfall, with and without the effects caused by transportation of radioactive debris from nuclear explosions...

  9. Artificial skin. Jinko hifu

    Kifune, K. (Unitika Ltd., Osaka (Japan))

    1993-06-15

    In order to restore the human skin wounds, the transplantation is only one measure. The transplantation can take only when own skin is used, and there is no successful example by using other person's skin. When the own skin is not sufficient due to the too vast damage, the artificial skin, which can be regenerated as it is, is required. The artificial skin is said to be the most difficult organ among the artificial organs, even though its function is quite simple. Although there are the pig skin, the collagen membrane and the synthetic materials such as the polyurethane and so forth, as the materials similar to the artificial skin, they cover the wounds just until the cuticle is formed. Recently there is a cultivated skin. Firstly the normal skin with a size of the stamp is cut off, and then the cuticle cells are taken to pieces and cultivated, and consequently it is possible to increase the area by several 10 times. In addition, there is also a trial to make the artificial skin synthetically. Its upper layer is composed of the silicon, and the lower layer is the collagen membrane with a sponge structure. The silicon, membrane can be said to be an ideal artificial skin, because it detaches naturally. The chitin, which has recently appeared as the wound protection material, is also the promising material. 3 figs.

  10. Application of biotechnology to the problem of the disposal of radioactive wastes

    Artificial biological systems are proposed for use in the treatment of low- and intermediate-level radioactive wastes. The microbial conversion of organic and inorganic substances under continuous conditions, involving the turnover of matter, will allow a significant reduction in volume of radioactive wastes. Such specialised systems can act as a biogeochemical barrier for radionuclide transport. 14 refs

  11. The role of chemistry in the history of radioactivity (1897-1939)

    Chemical research on radioactivity started in 1898. That year, Pierre and Marie Curie discovered in pitchblende polonium and radium. Rutherford and Soddy showed that radioactivity is an atomic phenomenon accompanied by transmutation of elements and established the basic laws of radioactive changes. The existence of isotopes was postulated after the discovery of many radioactive substances. Major discoveries in nuclear science, i.e. the atomic nucleus, the neutron and artificial radioactivity, were made with radiation sources elaborated bu chemists. Finally, in 1939, radiochemists on the search for transuranium elements, discovered nuclear fission. (authors)

  12. Experimental studies on utilization of argonless artificial air

    The radioactive argon produced in nuclear reactors causes environmental pollution. One of the substantial methods to reduce radioactive argon is the utilization of the artificial air with low argon content in reactor rooms. The artificial air close to natural air is obtainable by mixing commercial oxygen and nitrogen, however, there are some technical problems to be solved before it is solved. A small scale facility supplying artificial air was manufactured for trial, in order to find the optimum condition of controlling the mixing and to develop the continuous measurement method for the argon concentration in artificial air. In this study, the following facts have been found. For providing with the argonless artificial air close to natural air, the mixing of the gases evaporating from commercial liquid oxygen and nitrogen can be safely controlled. For the mixing control covering the wide range of flow rate, it is necessary to set up an auxiliary line in low flow range, in addition to the ordinary main line. The method of controlling the flow ratio of oxygen and nitrogen is not suitable to the control in low flow range. The oxygen concentration control method detecting it continuously is applicable to the control of whole flow range. The argon concentration is measured with an X-ray emission spectrometer. (Kako, I.)

  13. Radioactivity introduction and history, from the quantum to quarks

    L'Annunziata, Michael F

    2016-01-01

    As a comprehensive review of radioactivity from natural and artificial sources on earth and radiation of cosmic origins, this book provides users with a chronological account of the significant historical events on the topic dating from 1895 to the present, along with an introduction to the atom and its nucleus.

  14. Six-year experiences in the environmental radioactivity monitoring in Taiwan

    An islandwide network for environmental radioactivity monitoring established in 1974 is described with reference to (1) measurement of radioactive fallout from nuclear testings, (2) environmental monitoring for nuclear power plants and a radioactive waste disposal site, (3) a site specially designated by the government, and (4) installations involving radiation. Naturally occurring and artificial radionuclides are equally emphasized. All significant results are reported and discussed. (H.K.)

  15. Radioactive Iodine (Radioiodine) Therapy

    ... lymph nodes and other parts of the body. Radioactive iodine therapy improves the survival rate of patients with papillary ... and benefits of RAI therapy with your doctor. Radioactive iodine therapy cannot be used to treat anaplastic (undifferentiated) and ...

  16. Radioactivity in consumer products

    Moghissi, A.A.; Paras, P.; Carter, M.W.; Barker, R.F. (eds.)

    1978-08-01

    Papers presented at the conference dealt with regulations and standards; general and biological risks; radioluminous materials; mining, agricultural, and construction materials containing radioactivity; and various products containing radioactive sources.

  17. Radioactive waste management

    This booklet is a publication by International Atomic Energy Agency for general awareness of citizens and policy-makers to clarify their concept of nuclear wastes. In a very simple way it tells what is radioactivity, radiations and radioactive wastes. It further hints on various medial and industrial uses of radiations. It discusses about different types of radioactive wastes and radioactive waste management. Status of nuclear power plants in Central and Eastern European countries are also discussed

  18. Natural radioactivity and human mitochondrial DNA mutations

    Forster, Lucy; Forster, Peter; Lutz-Bonengel, Sabine; Willkomm, Horst; Brinkmann, Bernd

    2002-01-01

    Radioactivity is known to induce tumors, chromosome lesions, and minisatellite length mutations, but its effects on the DNA sequence have not previously been studied. A coastal peninsula in Kerala (India) contains the world's highest level of natural radioactivity in a densely populated area, offering an opportunity to characterize radiation-associated DNA mutations. We sampled 248 pedigrees (988 individuals) in the high-radiation peninsula and in nearby low-radiation islands as a control pop...

  19. Radioactivity measurements as tool for physics dissemination

    In general people associate environmental radioactivity with the artificial radioactivity and knows very little about natural radioactivity. Thus there is a critical need to improve nuclear physics public education. From 2005 in Italy two programs were promoted from Ministry of Education and University and National Institute of Nuclear Physics (INFN) for scientific dissemination in the field of environmental radioactivity. High school students in many Italian regions were involved in particular in indoor radon measurements. With this program students acquired awareness about the risks of inhalation of radon and its progeny and at the same time contributed to carry out radon monitoring, participating to all the experimental phases, from detectors set-up to data analysis. In particular we report about the activities carried out at Catania University and INFN division regarding a survey in the eastern Sicily. The overall monitoring, spanned over a period of 5 years, was carried out using passive nuclear track detection technique, through CR-39 dosimeters. In total about 500 detectors were placed in dwellings and schools in 57 locations. The investigated area have shown medium-high indoor radon concentrations, higher than the Italian average (70 Bq/m3). From the evaluation of the participating teachers and students, this kind of activities represents a successful strategy to enhance dissemination of physics, in particular in radioactivity topics. (author)

  20. Radioactive tracers in the sea

    Artificial radionuclides introduced to the oceans during the last four decades have proved invaluable tools for study of many processes in marine water columns and sediments. Both global and close-in fallout of radioactivity from atmospheric nuclear weapons testing have distributed these radionuclides widely, and in amounts sufficient to be useful as tracers. An additional source of considerable significance and tracer potential comes from coastal discharges of European nuclear fuel reprocessing wastes. The nature of these sources, types and amounts of radionuclides introduced and the time histories of their introduction generate a variety of tracer distributions which illuminate a broad spectrum of physical and chemical processes active over a wide range of timescales. Depending on their respective chemistries, artificial radionuclides have been demonstrated to exhibit both conservative and non-conservative properties in the oceans. Some examples are given of the uses made of soluble, conservative tracers for the study of oceanic transport processes and of non-conservative tracers for studies of processes which move them to, and mix them within, marine sediments. Sampling and measurement techniques which have been used in these studies are described

  1. Artificial intelligence in nanotechnology

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines. (topical review)

  2. Radioactivity in New Zealand meat products

    Full text: New Zealand has no nuclear power programme of radioactive waste disposal programme. The only artificial radioactivity detectable in the New Zealand environment is global fallout from nuclear weapons tests conducted mainly in the northern hemisphere before 1964. This fallout in New Zealand is currently at its lowest level since environmental monitoring began in 1960. The total beta activity deposited in rain during 1985, for example, averaged 76 MBQ/km2, with most of that being due to naturally occurring radionuclides, principally lead-210/Bismuth-210. Levels of artificial radioactivity in New Zealand dairy products reflect this very low deposition rate. During 1985, for example, Strontium-90 and Caesium-137 levels in cow's milk averaged 0.035 BG/GCA and 0.27BQ/QK respectively. Those levels were similar to, or less than, levels reported in northern hemisphere countries during 1985. No change in environmental contamination levels has been recorded in New Zealand during 1985. The very low deposition rate and milk contamination levels indicate that fallout contamination levels generally are insignificant in New Zealand and monitoring of other foodstuffs such as meat products is not warranted. (author)

  3. Artificial ionospheric turbulence (review)

    This study is an analysis of artificial ionospheric turbulence (AIT) arising near the level at which a powerful wave is reflected with ordinary polarization. AIT is an inhomogeneous structure in the ionosphere with a size on the order of centimeters or tens of kilometers and with characteristic frequencies from a fraction of a hertz (aperiodic inhomogeneity) to several megahertz (plasma waves). The authors are primarily concerned with small-scale artificial ionospheric turbulence (SAIT), i.e., with inhomogeneities that are greatly extended along the geomagnetic field with transverse dimensions that are less than the wavelengths of the perturbing waves - the pumping waves (PW) - in a vacuum

  4. Estimation of the chemical-induced eye injury using a weight-of-evidence (WoE) battery of 21 artificial neural network (ANN) c-QSAR models (QSAR-21): part I: irritation potential.

    Verma, Rajeshwar P; Matthews, Edwin J

    2015-03-01

    Evaluation of potential chemical-induced eye injury through irritation and corrosion is required to ensure occupational and consumer safety for industrial, household and cosmetic ingredient chemicals. The historical method for evaluating eye irritant and corrosion potential of chemicals is the rabbit Draize test. However, the Draize test is controversial and its use is diminishing - the EU 7th Amendment to the Cosmetic Directive (76/768/EEC) and recast Regulation now bans marketing of new cosmetics having animal testing of their ingredients and requires non-animal alternative tests for safety assessments. Thus, in silico and/or in vitro tests are advocated. QSAR models for eye irritation have been reported for several small (congeneric) data sets; however, large global models have not been described. This report describes FDA/CFSAN's development of 21 ANN c-QSAR models (QSAR-21) to predict eye irritation using the ADMET Predictor program and a diverse training data set of 2928 chemicals. The 21 models had external (20% test set) and internal validation and average training/verification/test set statistics were: 88/88/85(%) sensitivity and 82/82/82(%) specificity, respectively. The new method utilized multiple artificial neural network (ANN) molecular descriptor selection functionalities to maximize the applicability domain of the battery. The eye irritation models will be used to provide information to fill the critical data gaps for the safety assessment of cosmetic ingredient chemicals. PMID:25497990

  5. Production of artificial radioelements

    The techniques used in the production of artificial radioelements are described, with special emphasis on the following points: - nuclear reactions and use of reactors; - chemical separation methods and methods for enriching the activity of preparations; - protection of personnel and handling methods. (author)

  6. Artificial Left Ventricle

    Ranjbar, Saeed; Meybodi, Mahmood Emami

    2014-01-01

    This Artificial left ventricle is based on a simple conic assumption shape for left ventricle where its motion is made by attached compressed elastic tubes to its walls which are regarded to electrical points at each nodal .This compressed tubes are playing the role of myofibers in the myocardium of the left ventricle. These elastic tubes have helical shapes and are transacting on these helical bands dynamically. At this invention we give an algorithm of this artificial left ventricle construction that of course the effect of the blood flow in LV is observed with making beneficiary used of sensors to obtain this effecting, something like to lifegates problem. The main problem is to evaluate powers that are interacted between elastic body (left ventricle) and fluid (blood). The main goal of this invention is to show that artificial heart is not just a pump, but mechanical modeling of LV wall and its interaction with blood in it (blood movement modeling) can introduce an artificial heart closed to natural heart...

  7. Observations of artificial satellites

    A. MAMMANO

    1964-06-01

    Full Text Available The following publication gives the results of photographic
    observations of artificial satellites made at Asiago during the second
    and third year of this programme. The fixed camera technique and that
    with moving film (the latter still in its experimental stage have been used.

  8. Artificial intelligence within AFSC

    Gersh, Mark A.

    1990-01-01

    Information on artificial intelligence research in the Air Force Systems Command is given in viewgraph form. Specific research that is being conducted at the Rome Air Development Center, the Space Technology Center, the Human Resources Laboratory, the Armstrong Aerospace Medical Research Laboratory, the Armamant Laboratory, and the Wright Research and Development Center is noted.

  9. Terahertz Artificial Dielectric Lens

    Mendis, Rajind; Nagai, Masaya; Wang, Yiqiu; Karl, Nicholas; Mittleman, Daniel M.

    2016-03-01

    We have designed, fabricated, and experimentally characterized a lens for the THz regime based on artificial dielectrics. These are man-made media that mimic properties of naturally occurring dielectric media, or even manifest properties that cannot generally occur in nature. For example, the well-known dielectric property, the refractive index, which usually has a value greater than unity, can have a value less than unity in an artificial dielectric. For our lens, the artificial-dielectric medium is made up of a parallel stack of 100 μm thick metal plates that form an array of parallel-plate waveguides. The convergent lens has a plano-concave geometry, in contrast to conventional dielectric lenses. Our results demonstrate that this lens is capable of focusing a 2 cm diameter beam to a spot size of 4 mm, at the design frequency of 0.17 THz. The results further demonstrate that the overall power transmission of the lens can be better than certain conventional dielectric lenses commonly used in the THz regime. Intriguingly, we also observe that under certain conditions, the lens boundary demarcated by the discontinuous plate edges actually resembles a smooth continuous surface. These results highlight the importance of this artificial-dielectric technology for the development of future THz-wave devices.

  10. Artificial Gravity Research Plan

    Gilbert, Charlene

    2014-01-01

    This document describes the forward working plan to identify what countermeasure resources are needed for a vehicle with an artificial gravity module (intermittent centrifugation) and what Countermeasure Resources are needed for a rotating transit vehicle (continuous centrifugation) to minimize the effects of microgravity to Mars Exploration crewmembers.

  11. Spatially Resolved Artificial Chemistry

    Fellermann, Harold

    2009-01-01

    made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction...

  12. Natural or Artificial Intelligence?

    Havlík, Vladimír

    Plzeň: University of West Bohemia, 2013 - (Romportl, J.; Ircing, P.; Zackova, E.; Polak, M.; Schuster, R.), s. 15-27 ISBN 978-80-261-0275-5. [International Conference Beyond AI 2013. Plzeň (CZ), 12.11.2013-14.11.2013] Institutional support: RVO:67985955 Keywords : artificial intelligence * natural intelligence * artifact * natural process * intrinsic intentionality Subject RIV: AA - Philosophy ; Religion

  13. Artificial Intelligence and CALL.

    Underwood, John H.

    The potential application of artificial intelligence (AI) to computer-assisted language learning (CALL) is explored. Two areas of AI that hold particular interest to those who deal with language meaning--knowledge representation and expert systems, and natural-language processing--are described and examples of each are presented. AI contribution…

  14. Micromachined Artificial Haircell

    Liu, Chang (Inventor); Engel, Jonathan (Inventor); Chen, Nannan (Inventor); Chen, Jack (Inventor)

    2010-01-01

    A micromachined artificial sensor comprises a support coupled to and movable with respect to a substrate. A polymer, high-aspect ratio cilia-like structure is disposed on and extends out-of-plane from the support. A strain detector is disposed with respect to the support to detect movement of the support.

  15. Penetration by artificial electron acceptors of the plasma membrane-bound redox system into intact Zea mays L. roots investigated by proton-induced X-ray emission

    Proton-induced X-ray emission was used to investigate the penetration of compounds of the membrane-impermeant electron acceptors hexabromoiridate IV, hexachloroiridate IV, and hexacyanoferrate III into corn (Zea mays L.) roots. Maps of the heavy element distribution in cross-sections of fixed, epoxy-embedded roots showed for hexabromoiridate IV small amounts of Br in samples treated for 24 h with concentrations normally used in physiological experiments (0.02 mM). After treatment with high concentrations (0.8 mM) of these complexes, Fe and Ir as well as Br were found in root cross-sections. In samples taken at a distance of 5 mm behind the root tip, we found an even distribution of Fe, Ir, and Br over the whole cross-section. In samples taken 15 mm behind the root tip, about 99% of both Br and Ir was confined to the rhizodermal cell layer. The distribution did not change with the complex used. These data are consistent with the view that apoplastic diffusion of the electron acceptors was blocked by the hypodermal Casparian band

  16. Introduction to Artificial Neural Networks

    Larsen, Jan

    1999-01-01

    The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks.......The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks....

  17. Inflatable artificial sphincter - series (image)

    An artificial urinary sphincter is used to treat stress incontinence in men that is caused by urethral dysfunction such ... An artificial sphincter consists of three parts: a cuff that fits around the bladder neck a pressure regulating balloon ...

  18. RESPONSE CHARACTERISTICS OF WIND EXCITED CABLES WITH ARTIFICIAL RIVULET

    顾明; 刘慈军; 徐幼麟; 项海帆

    2002-01-01

    A wind tunnel investigation of response characteristics of cables with artificial rivulet is presented.A series of cable section models of different mass and stiffness and damping ratio were designed with artificial rivulet.They were tested in smooth flow under different wind speed and yaw angle and for different position of artificial rivulet.The measured response of cable models was then analyzed and compared with the experimental results obtained by other researchers and the existing theories for wind-induced cable vibration.The results show that the measured response of horizontal cable models with artificial rivulet could be well predicted by Den Hartog' s galloping theory when wind is normal to the cable axis.For the wind with certain yaw angles, the cable models with artificial rivulet exhibit velocity-restricted response characteristics.

  19. Charge distributions and coagulation of radioactive aerosols

    The self-charging of radioactive aerosols will be reduced by background ions, such as those produced by radioactive gases. The sources of these background ions and their production rates are specified for a reactor containment atmosphere during a possible nuclear accident. Previous theory is extended to calculate the charging of a polydisperse radioactive aerosol. Gaussian approximations to charge distributions on an aerosol of a given size, and are shown to give a good representation of the exact numerical charge distributions of a Cs aerosol at normal temperatures, and also for highly radioactive aerosol containing 131I in a containment atmosphere. Extensive calculations are performed for charged-induced modifications to Brownian coagulation rates between steady-state size distribution of these radioactive aerosols, and also between small-sized radioactive aerosol and larger (non-radioactive) aerosol. The results show considerable enhancements of the coagulation rates between large and small-sized aerosol, but also a strong suppression of coagulation between large particles. Rate modifications calculated using the Gaussian approximations are generally close to the exact values. Time-dependent calculations for a monodisperse α-decaying aerosol reveal enhancements in coagulation rates even when the average charge on the aerosol is positive. Our results are relevant to behaviour in a dusty plasma. (author)

  20. Radio-ecological aspects in artificial groundwater recharge

    In increasing extent surface waters, especially those of rivers and streams, are contaminated by radionuclides. Therefore it is necessary to investigate the possibility of impairement of the quality of artificially recharged groundwater and drinking water by radionuclides. Hazards for man are possible by drinking water, that was affected by waste and during exposition to air, as well as indirectly by irrigation water and the food chain. In a model calculation using realistic conditions the order of magnitude of these hazards for man by incorporation of radioactively contaminated artificially recharged drinking water are to be assessed. Here the parameters are discussed which must be considered in such an assessment. The model includes the use of river water for artificial recharge. All models and assessments assume the most unfavourable preconditions, which may lead to an impact to man. (orig.)

  1. Potentiated clinoptilolite: artificially enhanced aluminosilicate reduces symptoms associated with endoscopically negative gastroesophageal reflux disease and nonsteroidal anti-inflammatory drug induced gastritis

    Potgieter W

    2014-07-01

    clinoptilolite. Treatment with the potentiated clinoptilolite resulted in significant prevention (P≤0.05 of mucosal erosion severity as graded by the gastroenterologist.Conclusion: Absorbatox is a nonabsorbable aluminosilicate with potential gastroprotective benefits as it protected against ENGORD symptoms and NSAID-induced gastric events. The exact mechanism of action is not clear but may be due to its binding to hydrogen ions and biologically active amines and nitrates.Keywords: cation exchanger, gastro-protective agent, endoscopy, zeolite

  2. Artificial Intelligence and Information Retrieval.

    Teodorescu, Ioana

    1987-01-01

    Compares artificial intelligence and information retrieval paradigms for natural language understanding, reviews progress to date, and outlines the applicability of artificial intelligence to question answering systems. A list of principal artificial intelligence software for database front end systems is appended. (CLB)

  3. ORNL radioactive waste operations

    Since its beginning in 1943, ORNL has generated large amounts of solid, liquid, and gaseous radioactive waste material as a by-product of the basic research and development work carried out at the laboratory. The waste system at ORNL has been continually modified and updated to keep pace with the changing release requirements for radioactive wastes. Major upgrading projects are currently in progress. The operating record of ORNL waste operation has been excellent over many years. Recent surveillance of radioactivity in the Oak Ridge environs indicates that atmospheric concentrations of radioactivity were not significantly different from other areas in East Tennesseee. Concentrations of radioactivity in the Clinch River and in fish collected from the river were less than 4% of the permissible concentration and intake guides for individuals in the offsite environment. While some radioactivity was released to the environment from plant operations, the concentrations in all of the media sampled were well below established standards

  4. Radioactive air sampling methods

    Maiello, Mark L

    2010-01-01

    Although the field of radioactive air sampling has matured and evolved over decades, it has lacked a single resource that assimilates technical and background information on its many facets. Edited by experts and with contributions from top practitioners and researchers, Radioactive Air Sampling Methods provides authoritative guidance on measuring airborne radioactivity from industrial, research, and nuclear power operations, as well as naturally occuring radioactivity in the environment. Designed for industrial hygienists, air quality experts, and heath physicists, the book delves into the applied research advancing and transforming practice with improvements to measurement equipment, human dose modeling of inhaled radioactivity, and radiation safety regulations. To present a wide picture of the field, it covers the international and national standards that guide the quality of air sampling measurements and equipment. It discusses emergency response issues, including radioactive fallout and the assets used ...

  5. Radioactivity Monitoring of the Irish Environment 2010-2011

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland RPII during 2010 and 2011. The RPII has routinely monitored levels of radioactivity in the Irish environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The data presented in this report confirm that while the levels of artificial radioactivity in the Irish environment are detectable, they are low. They do not pose a significant risk to the human health of the Irish population. Trace amounts of radioactive isotopes consistent with the Fukushima nuclear accident were detected in air, rainwater and milk samples during the period March to May 2011. These increases in levels of radioactivity were not of concern from a public health point of view. For the remainder of the reporting period, activity concentrations of radionuclides in airborne particles were low and consistent with measurements made in recent years. Radioactivity levels in milk, mixed diet and a wide range of foodstuffs were low and, for the majority of samples, below the detection limits. All drinking waters tested were found to be in compliance with the total indicative dose defined in national and EU legislation. The doses incurred by the Irish public in 2010 and 2011 as a result of artificial radioactivity in the marine environment are small when compared to dose limits or to natural radiation doses received by the Irish public. The doses to the most exposed individuals, members of the oyster and mussel farmers critical group, were approximately 0.02 per cent and 0.05 per cent of the annual dose limit of 1000 microsieverts for members of the public from practices involving controllable sources of radiation in 2010 and

  6. Comparisons between radioactive and non-radioactive gas lantern mantles

    Gas lantern mantles containing radioactive thorium have been used for more than 100 years. Although thorium was once believed to be indispensable for giving a bright light, non-radioactive mantles are now available. From the radioactivities of the daughter nuclides, we estimated the levels of radioactivity of 232Th and 228Th in 11 mantles. The mantles contained various levels of radioactivity from background levels to 1410±140 Bq. Our finding that radioactive and non-radioactive mantles are equally bright suggests that there is no advantage in using radioactive mantles. A remaining problem is that gas lantern mantles are sold without any information about radioactivity. (author)

  7. Categorization of Radioactive Sources. Safety Guide

    Radioactive sources are used throughout the world in medicine, industry, agriculture, research and education. They are also used in some military applications. Many are in the form of sealed sources with the radioactive materials firmly contained or bound within a suitable capsule or housing. The risks posed by these sources vary widely, depending on such factors as the radionuclides used, the physical and chemical form and the activity. Sealed sources, unless they have been breached or are leaking, present a risk of external radiation exposure only. However, breached or leaking sealed sources, as well as unsealed radioactive materials, may give rise to contamination of the environment and the intake of radioactive materials into the human body. Until the 1950s, only radionuclides of natural origin, particularly 226Ra, were generally available for use. Since then, radionuclides produced artificially in nuclear facilities and accelerators, including 60Co, 90Sr, 137Cs and 192Ir, have become widely used. The International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) provide an internationally harmonized basis for ensuring the safe and secure use of sources of ionizing radiation, and the Safety Requirements for Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety set out the essential elements of a regulatory control system. Sealed and unsealed radioactive sources are used for a variety of purposes and they incorporate a wide range of radionuclides and amounts of radioactive material. High activity sources, if not managed safely and securely, can cause severe deterministic effects to individuals in a short period of time, whereas low activity sources are unlikely to cause exposures with harmful consequences. his Safety Guide provides a risk based ranking of radioactive sources and practices in five categories. The categorization system is based on a logical

  8. Categorization of radioactive sources. Safety guide

    Radioactive sources are used throughout the world in medicine, industry, agriculture, research and education; they are also used in some military applications. Many are in the form of sealed sources with the radioactive materials firmly contained or bound within a suitable capsule or housing. The risks posed by these sources vary widely, depending on such factors as the radionuclides used, the physical and chemical form and the activity. Sealed sources, unless they have been breached or are leaking, present a risk of external radiation exposure only. However, breached or leaking sealed sources, as well as unsealed radioactive materials, may give rise to contamination of the environment and the intake of radioactive materials into the human body. Until the 1950s, only radionuclides of natural origin, particularly 226Ra, were generally available for use. Since then, radionuclides produced artificially in nuclear facilities and accelerators, including 60Co, 90Sr, 137Cs and 192Ir, have become widely used. The International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) provide an internationally harmonized basis for ensuring the safe and secure use of sources of ionizing radiation, and the Safety Requirements for Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety set out the essential elements of a regulatory control system. Sealed and unsealed radioactive sources are used for a variety of purposes and they incorporate a wide range of radionuclides and amounts of radioactive material. High activity sources, if not managed safely and securely, can cause severe deterministic effects to individuals in a short period of time, whereas low activity sources are unlikely to cause exposures with harmful consequences. his Safety Guide provides a risk based ranking of radioactive sources and practices in five categories. The categorization system is based on a logical

  9. Radioactive wastes and discharges

    The guide sets out the radiation safety requirements and limits for the treatment of radioactive waste. They shall be observed when discharging radioactive substances into the atmosphere or sewer system, or when delivering solid, low-activity waste to a landfill site without a separate waste treatment plan. The guide does not apply to the radioactive waste resulting from the utilisation of nuclear energy or natural resources

  10. Radioactivity and its measurement

    Mann, W B; Garfinkel, S B

    1980-01-01

    Begins with a description of the discovery of radioactivity and the historic research of such pioneers as the Curies and Rutherford. After a discussion of the interactions of &agr;, &bgr; and &ggr; rays with matter, the energetics of the different modes of nuclear disintegration are considered in relation to the Einstein mass-energy relationship as applied to radioactive transformations. Radiation detectors and radioactivity measurements are also discussed

  11. Learning more about radioactivity

    This digest brochure explains what radioactivity is, where it comes from, how it is measured, what are its effects on the body and the way to protect it against these effects, the uses of radioactivity (In the medical field, In industry, In the food industry, and In the cultural world). It ends with some examples of irradiation levels, of natural radioactivity and with the distribution in France of various sources of exposure. (J.S.)

  12. Biokinetics of radioactive compounds

    Biokinetics of radioactive compounds in the human organism represent the central notion in this work, consisting of a theoretical and an experimental part. The first chapter contains definitions and explanations on the importance of the biokinetics of radioactive compounds in clinical therapy and pharmaceuticals research as well as for assessing radiation exposure and radiation hazards. Chapter 2 describes the bases of the biokinetics of radioactive compounds in the medical and non-medical sector, and biokinetics. Chapter 3 deals with obtaining biokinetics data for radioactive compounds from investigations in animals and man, evaluation of measurements, transferring data obtained by animal experiments to man, and with the variability of biokinetics data. In Chapter 4 the results of comprehensive studies in literature on the biokinetics of radioactive compounds are summarized. They relate to three areas: professional and environmental incorporation of radioactive compounds, use of radioactive pharmaceuticals in therapy and research, and incorporation of radioactive compounds by embryo and fetus in consequence of the uptake of radioactive compounds by the mother. Chapter 5 gives an assessment of radiation hazards from radioactive compounds in connection with occupational radiation exposure and nuclear diagnostics in vivo, and a comparison with other risks. For that purpose the concept of effective dose equivalent is applied in connection with suitable risk coefficients to professional and nuclear-medical radiation exposure. Chapter 6 is dedicated to measurement of the biokinetics of radioactive compounds in man using conventional devices. The object of Chapter 7 is measurement of the biokinetics of radioactive pharmaceuticals in man by means of single photon emission computed tomography. (orig./MG)

  13. Drainage of radioactive areas

    This Code of Practice covers all the drainage systems which may occur in the radioactive classified area of an establishment, namely surface water, foul, process and radioactive drainage. It also deals with final discharge lines. The Code of Practice concentrates on those aspects of drainage which require particular attention because the systems are in or from radioactive areas and typical illustrations are given in appendices. The Code makes references to sources of information on conventional aspects of drainage design. (author)

  14. Radioactive wastes and discharges

    NONE

    2000-07-01

    The guide sets out the radiation safety requirements and limits for the treatment of radioactive waste. They shall be observed when discharging radioactive substances into the atmosphere or sewer system, or when delivering solid, low-activity waste to a landfill site without a separate waste treatment plan. The guide does not apply to the radioactive waste resulting from the utilisation of nuclear energy or natural resources.

  15. Measurement of environmental radioactivity in Toki district

    When the Institute of Plasma Physics, Nagoya University, expressed the hope to move into Toki district, the environmental problems accompanying the movement were discussed. The effect of the radioactivity leaking from the nuclear facility on human bodies must be far smaller than that of natural radiation, and for the purpose, the amount and fluctuation range of the natural radiation in the district must be known. The initial objectives of this cooperative research were to study on environmental radiation and to make a Geiger counter for the measurement. In 1981, a scintillation counter will be completed, and using a multi-channel pulse height analyzer, the nuclides which are the source of environmental radiation emission will be identified, and the tritium in natural water will be detected. Thus, the evaluation of environmental radiation can be carried out, and the situation before the movement of the research facility can be grasped. In this paper, the natural radioactivity in earth, atmosphere and water and cosmic ray, artificial radioactivity, and environmental radiation exposure dose are reported. Also, the manufacture of a GM counter measuring instrument and the measurements of cosmic ray background, typical earth samples and environmental radioactivity with the GM counter are reported. The related data are attached. (Kako, I.)

  16. Radioactive Plumes Monitoring Simulator

    The Airborne Radiation Monitoring System (ARMS) monitors air or ground radioactive contamination. The contamination source can be a radioactive plume or an area contaminated with radionuclides. The system is based on two major parts, an airborne unit carried by a helicopter and a ground station carried by a truck. The system enables real time measurement and analysis of radioactive plumes as well as post flight processing. The Radioactive Plumes Monitoring Simulator purpose is to create a virtual space where the trained operators experience full radiation field conditions, without real radiation hazard. The ARMS is based on a flying platform and hence the simulator allows a significant reduction of flight time costs

  17. Controlling radioactive waste

    The guideline of the Ministry for Environmental Protection for controlling radioactive waste with a negligible development of heat defines in detail what data are relevant to the control of radioactive waste and should be followed up on and included in a system of documentation. By introducing the AVK (product control system for tracing the course of waste disposal) the operators of German nuclear power plants have taken the requirements of this guideline into account. In particular, possibilities for determining the degree of radioactivity of radioactive waste, which the BMU-guidelines call for, were put into practice by means of the programming technology of the product control system's module MOPRO. (orig.)

  18. Survey monitoring of environmental radioactivity in Daegu area

    Kang, H. D.; Lee, S. Y. [Kyungpook National Univ., Daegu (Korea, Republic of)

    1998-01-15

    The objectives of the project are to monitor an abnormal radiation level in Taegu and Kyungpook region, and to enhance our ability to prepare for the radiological emergency situation by establishing the radioactivity monitoring system in Taegu and Kyungpook region. Gross beta activities were measured and gamma radionuclides were analysed for the environmental samples of air-borned dust. precipitation. fallout and drinking water collected in Taegu radioactivity monitoring center. and gamma exposure rates were also measured. To establish the basic data base on the environmental radioactivity, gamma radionuclide analyses were carried out for the samples of soil, drinking water, grain, vegetable, milk, and fish which were obtained from 31 different areas, and the spatial gamma exposure rates from 61 different points were also measured in Taegu and Kyungpook region. In conclusion, it didn't appear any evidence for newly pollution of artificial radioactivity in Taegu and Kyungpook region.

  19. Artificial Enzymes, "Chemzymes"

    Bjerre, Jeannette; Rousseau, Cyril Andre Raphaël; Pedersen, Lavinia Georgeta M;

    2008-01-01

    Enzymes have fascinated scientists since their discovery and, over some decades, one aim in organic chemistry has been the creation of molecules that mimic the active sites of enzymes and promote catalysis. Nevertheless, even today, there are relatively few examples of enzyme models that...... successfully perform Michaelis-Menten catalysis under enzymatic conditions (i.e., aqueous medium, neutral pH, ambient temperature) and for those that do, very high rate accelerations are seldomly seen. This review will provide a brief summary of the recent developments in artificial enzymes, so called...... "Chemzymes", based on cyclodextrins and other molecules. Only the chemzymes that have shown enzyme-like activity that has been quantified by different methods will be mentioned. This review will summarize the work done in the field of artificial glycosidases, oxidases, epoxidases, and esterases, as well as...

  20. Measurement of natural and 137Cs radioactivity concentrations at Izmit Bay (Marmara Sea), Turkey

    Öksüz, I.; Güray, R. T.; Özkan, N.; Yalçin, C.; Ergül, H. A.; Aksan, S.

    2016-03-01

    In order to determine the radioactivity level at Izmit Bay Marmara Sea, marine sediment samples were collected from five different locations. The radioactivity concentrations of naturally occurring 238U, 232Th and 40K isotopes and also that of an artificial isotope 137Cs were measured by using gamma-ray spectroscopy. Preliminary results show that the radioactivity concentrations of 238U and 232Th isotopes are lower than the average worldwide values while the radioactivity concentrations of the 40K are higher than the average worldwide value. A small amount of 137Cs contamination, which might be caused by the Chernobyl accident, was also detected.

  1. Artificial organisms that sleep.

    Mirolli, Marco; Parisi, Domenico

    2003-01-01

    Abstract Populations of artificial organisms live in an environment in which light is cyclically present (day) or absent (night). Since being active during night is non-adaptive (activity consumes energy which is not compensated by the food found at night) the organisms evolve a sleep/wake behavioral pattern of being active during daytime and sleeping during nighttime. When the population moves to a different environment that contains "caves", they have to get out of a cave although the dark ...

  2. Impacts of Artificial Intelligence

    Trappl, R.

    1986-01-01

    This book, which is intended to serve as the first stage in an iterative process of detecting, predicting, and assessing the impacts of Artificial Intelligence opens with a short "one-hour course" in AI, which is intended to provide a nontechnical informative introduction to the material which follows. Next comes an overview chapter which is based on an extensive literature search, the position papers, and discussions. The next section of the book contains position papers whose richness...

  3. Artificial Neural Network

    Kapil Nahar

    2012-12-01

    Full Text Available An artificial neural network is an information-processing paradigm that is inspired by the way biological nervous systems, such as the brain, process information. The key element of this paradigm is the novel structure of the information processing system. It is composed of a large number of highly interconnected processing elements (neurons working in unison to solve specific problems. Ann’s, like people, learn by example.

  4. Artificial Intelligence in Transition

    Hart, Peter E.

    1984-01-01

    In the past fifteen years artificial intelligence has changed from being the preoccupation of a handful of scientists to a thriving enterprise that has captured the imagination of world leaders and ordinary citizens alike. While corporate and government officials organize new projects whose potential impact is widespread, to date few people have been more affected by the transition than those already in the field. I review here some aspects of this transition, and pose some issues that it rai...

  5. Artificial neural network modelling

    Samarasinghe, Sandhya

    2016-01-01

    This book covers theoretical aspects as well as recent innovative applications of Artificial Neural networks (ANNs) in natural, environmental, biological, social, industrial and automated systems. It presents recent results of ANNs in modelling small, large and complex systems under three categories, namely, 1) Networks, Structure Optimisation, Robustness and Stochasticity 2) Advances in Modelling Biological and Environmental Systems and 3) Advances in Modelling Social and Economic Systems. The book aims at serving undergraduates, postgraduates and researchers in ANN computational modelling. .

  6. Intelligence, Artificial and Otherwise

    Chace, William M.

    1984-01-01

    I rise now to speak with the assumption that all of you know very well what I am going to say. I am the humanist here, the professor of English. We humanists, when asked to speak on questions of science and technology, are notorious for offering an embarrassed and ignorant respect toward those matters, a respect, however, which can all too quickly degenerate into insolent condescension. Face to face with the reality of computer technology, say, or with "artificial intelligence," we humanists ...

  7. Artificial sweetener; Jinko kanmiryo

    NONE

    1999-08-01

    The patents related to the artificial sweetener that it is introduced to the public in 3 years from 1996 until 1998 are 115 cases. The sugar quality which makes an oligosaccharide and sugar alcohol the subject is greatly over 28 cases of the non-sugar quality in the one by the kind as a general tendency of these patents at 73 cases in such cases as the Aspartame. The method of manufacture patent, which included new material around other peptides, the oligosaccharide and sugar alcohol isn`t inferior to 56 cases of the formation thing patent at 43 cases, and pays attention to the thing, which is many by the method of manufacture, formation. There is most improvement of the quality of sweetness with 31 cases in badness of the aftertaste which is characteristic of the artificial sweetener and so on, and much stability including the improvement in the flavor of food by the artificial sweetener, a long time and dissolution, fluid nature and productivity and improvement of the economy such as a cost are seen with effect on a purpose. (NEDO)

  8. Marcos da história da radioatividade e tendências atuais Landmarks in the history of radioactivity and current tendencies

    Allan Moreira Xavier; André Gomes de Lima; Camila Rosa Moraes Vigna; Fabíola Manhas Verbi; Gisele Gonçalves Bortoleto; Karen Goraieb; Carol Hollingworth Collins; Maria Izabel Maretti Silveira Bueno

    2007-01-01

    The first days of radioactivity, the discoveries of X-rays, radioactivity, of alpha- and beta- particles and gamma- radiation, of new radioactive elements, of artificial radioactivity, the neutron and positron and nuclear fission are reviewed as well as several adverse historical marks, such as the Manhattan project and some nuclear and radiological accidents. Nuclear energy generation in Brazil and the world, as an alternative to minimize environmental problems, is discussed, as are the medi...

  9. National policy and experience with the management of radioactive wastes from non-fuel cycle activities in the Czech Republic

    Research, production, and application of radioisotopes in many fields of science, industry, agriculture, medicine, education, etc. proceeded in the former Czechoslovak Republic (CSFR) since the mid-fifties. These activities resulted in a great accumulation of relatively large volumes and activities of radioactive wastes. Therefore, in 1959 the Czechoslovak government appointed the Institute for Research, Production, and Application of Radioisotopes (IRPAR), now NYCOM, to be the central authority for collection and disposal of these radioactive wastes. In 1972 these responsibilities were defined in more detail by the decree of the Ministry of Health of the Czech Republic No. 59/1972 on the protection of public health against the effects of ionizing radiation. From the very beginning the services for collection, transport, and disposal provided by IRPAR (NYCOM) were based on the concept of waste concentration and their safe disposal in well-controlled facilities. The aim of disposal is to guarantee that man and his environment will not suffer, neither at present nor in the future, from these wastes. This aim is achieved by isolation of radioactive wastes from the human environment by a system of multiple barriers for a sufficiently long period of time to allow activity to decay below acceptable limits. The disposal of radioactive wastes in the central repositories started in 1959, when the first repository located near the village Hostim in the Beroun District was put in operation. The operational period of this repository was ended in 1963 and it was closed in 1965. At present, there are other two repositories in operation. The repository Richard serves for disposal of wastes containing artificial radionuclides, i.e., nuclides with induced radioactivity and fission products. The repository Bratrstvi serves for disposal of naturally occurring radionuclides, i.e., nuclides of uranium and thorium and their daughter products. (author). 2 refs, 2 figs

  10. Characteristics and Disposal Categorization of Solid Radioactive Waste from the Front End of the Uranium Fuel Cycle

    The proper categorization of radioactive waste forms the basis for defining its disposal method. In particular, it is the basis for defining the disposal policy for solid radioactive waste from the front end of the uranium fuel cycle to identify scientifically its characteristics, in view of the differences in regulatory approach between artificial radioactive waste and NORM waste. The paper examines the disposal policy and practice in China and other countries for solid radioactive waste from the front end of the uranium fuel cycle and discusses the confusion in disposal of the waste as artificial radioactive waste. The radionuclide composition and characteristics of the solid radioactive waste from the front end of the uranium fuel cycle are investigated in detail and a new idea that such waste needs to be disposed of and categorized as NORM waste is proposed. (author)

  11. Artificial sweeteners--do they bear a carcinogenic risk?

    Weihrauch, M R; Diehl, V

    2004-10-01

    Artificial sweeteners are added to a wide variety of food, drinks, drugs and hygiene products. Since their introduction, the mass media have reported about potential cancer risks, which has contributed to undermine the public's sense of security. It can be assumed that every citizen of Western countries uses artificial sweeteners, knowingly or not. A cancer-inducing activity of one of these substances would mean a health risk to an entire population. We performed several PubMed searches of the National Library of Medicine for articles in English about artificial sweeteners. These articles included 'first generation' sweeteners such as saccharin, cyclamate and aspartame, as well as 'new generation' sweeteners such as acesulfame-K, sucralose, alitame and neotame. Epidemiological studies in humans did not find the bladder cancer-inducing effects of saccharin and cyclamate that had been reported from animal studies in rats. Despite some rather unscientific assumptions, there is no evidence that aspartame is carcinogenic. Case-control studies showed an elevated relative risk of 1.3 for heavy artificial sweetener use (no specific substances specified) of >1.7 g/day. For new generation sweeteners, it is too early to establish any epidemiological evidence about possible carcinogenic risks. As many artificial sweeteners are combined in today's products, the carcinogenic risk of a single substance is difficult to assess. However, according to the current literature, the possible risk of artificial sweeteners to induce cancer seems to be negligible. PMID:15367404

  12. Preparation of radioactive tracer for studying sediment movement

    In order to study the movement of sediment in harbours, estuaries and streams, artificial sediment in the form of glass is prepared. A preselected nuclide is added to the glass during its manufacture. The density and size distribution of the glass particles is method with that of the natural sediment. The activation of the artificial sediment in a reactor changes the nuclide into a radioactive isotope thereby tagging it and making it possible to trace its movement with suitable radiation detector. The method of tracer preparation is described with special reference to sadiment movement studies at Karachi harbour. (authors)

  13. A Remote Radioactivity Experiment

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one…

  14. Treatment of radioactive wastes

    This report is a review of some waste management activities including sources, system of collection and treatment of radioactive wastes. The report also includes methods and options used for treatment of liquid and solid radioactive wastes. (author). 26 refs., 5 figs., 6 tabs

  15. Transport of Radioactive Materials

    This address overviews the following aspects: concepts on transport of radioactive materials, quantities used to limit the transport, packages, types of packages, labeling, index transport calculation, tags, labeling, vehicle's requirements and documents required to authorize transportation. These requirements are considered in the regulation of transport of radioactive material that is in drafting step

  16. Environmental radioactivity in Turkey, 2010

    In this report, the activity concentrations of natural and artificial radionuclides and gross alpha/beta activities measured in the environmental and food samples provided from 81 provinces of the country within the environmental radioactivity monitoring program in 2010 and outdoor gamma dose rates obtained by means of car-borne measurement system are presented. The activity concentrations of the natural and artificial radionuclides in the samples were measured by using the gamma spectrometry, the alpha spectrometry, the liquid scintillation counter and the gross alpha /beta counting system. The mean activity concentrations of 226Ra, 232Th and 40K in the analyzed surface samples were found as 28.11±1.23 Bq kg-1, 32.4±1.2 Bq kg-1 and 430.8±12.5, respectively, while the mean activity concentration of the fission product 137Cs was found as 9.78±0.79 Bq kg-1. The mean absorbed gamma dose rate in outdoor due to external exposure emitted by natural radionuclides in soil samples and the corresponding annual effective dose were evaluated as 50.5 nGy h-1 and 0.062 mSv y-1, respectively. Total indicative doses of the analyzed drinking water samples were below the limit values. The activity concentrations of 238U, 232Th and 226Ra in the analyzed food samples were lower than the minimum detectable activity while 134Cs radionuclide was not observed. The mean activity concentrations of 137Cs and 90Sr radionuclides measured in the milk samples are 1.01 Bq L-1 and 0.29 Bq L-1, respectively. These values are lower than the limit value specified for foods subjected to control based on the regulation of the EU 737/90/EC. The total annual effective dose arising from the internal exposure from radiation emitting from 40K, 137Cs and 90Sr radionuclides analyzed in the food samples are evaluated as 196.6 Sv. In conclusion, the results of the monitoring program in 2010 show that the levels of radioactivity in the environment are low and do not pose any significant risk to human health

  17. Environmental radioactivity in Turkey, 2009

    In this report, the activity concentrations of natural and artificial radionuclides and gross alpha/beta activities measured in the environmental and food samples provided from Turkey's seven geographical regions within the environmental radioactivity monitoring program in 2009 and absorbed gamma dose rates in outdoor obtained by means of car-borne measurement system (Mobysis) are presented. The activity concentrations of the natural and artificial radionuclides and gross alpha/beta activities in the samples were measured by using the gamma spectrometry, the alpha spectrometry, the liquid scintillation counter and the gross alpha /beta counting system. The mean activity concentrations of 226Ra, 232Th and 40K in the analyzed surface samples were found as 34,7 ± 1,7 Bq kg-1, 35,4 ± 0,8 Bq kg-1 and 450,0 ± 17,9 Bq kg-1, respectively, while the mean activity concentration of the fission product 137Cs was found as 11,6 ± 0,5 Bq kg-1. The mean absorbed gamma dose rate in outdoor due to external exposure emitted by natural radionuclides in soil samples and the corresponding annual effective dose were evaluated as 54,6 nGy h-1 and 0,07 mSv y-1, respectively. The activity concentrations of 238U, 232Th and 226Ra in the analyzed food samples were lower than the minimum detectable activity (MDA) while 134Cs radionuclide was not observed. The mean activity concentrations of 137Cs and 90Sr radionuclides measured in the milk samples are 0,28 Bq L-1 and 0.05 Bq L-1, respectively. These values are lower than the limit value specified for foods subjected to control based on the regulation of the EU 737/90/EC. The total annual effective dose arising from the internal exposure from radiation emitting from 40K, l37Cs and 90Sr radionuclides analyzed in the food samples are evaluated as 193,0 μSv. In conclusion, the results of the monitoring programme in 2009 show that the levels of radioactivity in the environment are low and do not pose any significant risk to human health and the

  18. Radioactivity: additional tables

    The following additional tables are presented to the annual report on radioactive discharges from the major establishments in the U.K.: 1) Radioactive gaseous effluent, trends in annual emissions, by site, (civil and M.O.D.) 2) Radioactive liquid effluent (radionuclides specified by authorisations), trends in annual discharges to surface and coastal waters: by site. 3) Liquid effluent (radionuclides not subject to separate limits): annual discharges to surface and coastal waters by site. 4) Isotopic composition of liquid effluent from CEGB stations, 1984. 5) Trends in the amount of radioactivity in waste dumped in the north-east Atlantic. 6) Trends in volume of waste disposed of at Drigg (by source of waste). 7) Solid waste: trends in volume disposed of and level of activity at some other disposal sites. 8) Radioactivity in samples of fish and shellfish: trends in concentrations. (UK)

  19. Radioactive sodium processing apparatus

    Purpose: To enable safety, continuous and economical disposal for radioactive sodium while preventing radioactive contaminations. Constitution: Reaction gas introduction pipe for introducing oxygen and carbon dioxygen, and steams for accelerating the processing speed, as well as a discharge pipe for sodium carbonate as reaction products are connected to the lower side wall of a radioactive sodium processing container. A screw conveyor is mounted within the radioactive sodium processing container and a torque meter is disposed in the central axis of the conveyor. Signals from the torque meter are sent to an oxygen introduction control device. V-shaped recesses are formed to the screw blades of the conveyor for improving the separating efficiency between sodium carbonate produced through the procession and not-processed radioactive sodium. Since sodium is converted after the process into sodium carbonate, it can be handled and stored within ease. (Yoshihara, H.)

  20. EPA's Radioactive Source Program

    The US EPA is the lead Federal agency for emergency responses to unknown radiological materials, not licensed, owned or operated by a Federal agency or an Agreement state (Federal Radiological Emergency Response Plan, 1996). The purpose of EPA's clean materials programme is to keep unwanted and unregulated radioactive material out of the public domain. This is achieved by finding and securing lost sources, maintaining control of existing sources and preventing future losses. The focus is on both, domestic and international fronts. The domestic program concentrates on securing lost sources, preventing future losses, alternative technologies like tagging of radioactive sources in commerce, pilot radioactive source roundup, training programs, scrap metal and metal processing facilities, the demolition industry, product stewardship and alternatives to radioactive devices (fewer radioactive source devices means fewer orphan sources). The international program consists of securing lost sources, preventing future losses, radiation monitoring of scrap metal at ports and the international scrap metal monitoring protocol

  1. Evaluation of Terrorist Interest in Radioactive Wastes

    analysis is that environmental management generated radioactive wastes have substantially less impact than radioactive sources if dispersed by terrorist-induced explosion or fire. From a health standpoint, the impact is very small. However, there is no basis to conclude that wastes are totally unattractive for use in a disruptive or economic damage event. Waste managers should be cognizant of this potential and take measures to ensure security of stored waste and waste shipments. (authors)

  2. Radioactive accumulation in alga samples from Romanian Black Sea coast

    The natural and artificial radioactivity of the brown alga Cystoseira barbata samples collected on the Romanian Black Sea coast in 1996 in reported. The results on 137Cs were obtained through gamma-spectrometry, on 90Sr by beta-counting of the 90Y oxalate precipitated after strontium separation, on 226Ra by the emanation method, while the concentrations of U, Th, Pu and Am isotopes were obtained through radiochemical separations using tracers followed by alpha-spectrometry counting of the stainless steel discs after electrodeposition. These results add further evidence that Cystoseira barbata may be used as a bioindicator for radioactive contamination of the coastal waters. (author)

  3. Gross alpha radioactivity of drinking water in Venezuela

    Bottled mineral water is consumed by a large population in Venezuela. The alpha emitters concentration was measured in samples of bottled water and water springs collected near the surface. Approximately 30% of the total mineral water suppliers was monitored. a database on natural and artificial radioactivity in drinking water was produced. Results indicate that 54% of the waters sampled contain a total alpha radioactivity of less than 0.185 Bql-1 and only 12% above 0.37 Bql-1. Our results revealed a total annual dose of 2.3 mSv year-1. (author)

  4. Measurement of radioactivity in agricultural products (1995-96)

    Radioactivity levels and concentration of radionuclides in agricultural products like beans, sesame, potato, etc. were measured by using Low Level Beta/Alpha System and high resolution gamma-ray spectrometry system. The levels of radioactivity were found to be less than the Derivedc Intervention Level adopted by FAO/WHO Codex Alimentarius Commission in 1991 (IAEA BSS safety series No. 115-1). No artificial radionuclides such as fission products, activation products were not found whereas radionuclides found in the samples are only natural occurring radionuclide, K-40. (author)

  5. Radioactivity in a mountain ecosystem: the Haut Bassin du Var

    After the Chernobyl accident, the IPSN realized a study of the radioactive fallout in the mountain area of the Var (France). Today the main radionuclides are the cesium 134 and 137, others disappeared because of their short half-life. In this paper, the artificial radioactivity of soils and sediments is concerned. The study shows a concentration of the contamination in some specific areas, especially in soils abounding in organic matter. The dose measured can not lead to significant exposures. (A.L.B.)

  6. Radioactivity of household water in Finland

    A nationwide study on artificial and natural radioactivity in household water has been under way in Finland since the 1960s. The occurrence of artificial radionuclides in the surface water of drainage basins has been monitored extensively. The proportion of household water derived from surface waters in Finland is currently 48 %, but its usage is decreasing whereas that of groundwater is increasing at an annual rate of 1 - 2 %. The natural radioactivity of household water has been studied in almost all of the waters distributed by public waterworks and in 5400 private ground water wells. The downward trend in 90Sr, 137Cs and 3H concentrations in surface water continued from the middle 1960s until the Chernobyl accident. After the accident ten different radionuclides were detected in surface waters, but only 137Cs made a minor contribution the radiation dose. The maximum effective dose via ingestion of water was about 0.001 mSv in 1986, and considerably lower in the following years

  7. Artificial intelligence in hematology.

    Zini, Gina

    2005-10-01

    Artificial intelligence (AI) is a computer based science which aims to simulate human brain faculties using a computational system. A brief history of this new science goes from the creation of the first artificial neuron in 1943 to the first artificial neural network application to genetic algorithms. The potential for a similar technology in medicine has immediately been identified by scientists and researchers. The possibility to store and process all medical knowledge has made this technology very attractive to assist or even surpass clinicians in reaching a diagnosis. Applications of AI in medicine include devices applied to clinical diagnosis in neurology and cardiopulmonary diseases, as well as the use of expert or knowledge-based systems in routine clinical use for diagnosis, therapeutic management and for prognostic evaluation. Biological applications include genome sequencing or DNA gene expression microarrays, modeling gene networks, analysis and clustering of gene expression data, pattern recognition in DNA and proteins, protein structure prediction. In the field of hematology the first devices based on AI have been applied to the routine laboratory data management. New tools concern the differential diagnosis in specific diseases such as anemias, thalassemias and leukemias, based on neural networks trained with data from peripheral blood analysis. A revolution in cancer diagnosis, including the diagnosis of hematological malignancies, has been the introduction of the first microarray based and bioinformatic approach for molecular diagnosis: a systematic approach based on the monitoring of simultaneous expression of thousands of genes using DNA microarray, independently of previous biological knowledge, analysed using AI devices. Using gene profiling, the traditional diagnostic pathways move from clinical to molecular based diagnostic systems. PMID:16203606

  8. Polymer artificial muscles

    Tissaphern Mirfakhrai

    2007-04-01

    Full Text Available The various types of natural muscle are incredible material systems that enable the production of large deformations by repetitive molecular motions. Polymer artificial muscle technologies are being developed that produce similar strains and higher stresses using electrostatic forces, electrostriction, ion insertion, and molecular conformational changes. Materials used include elastomers, conducting polymers, ionically conducting polymers, and carbon nanotubes. The mechanisms, performance, and remaining challenges associated with these technologies are described. Initial applications are being developed, but further work by the materials community should help make these technologies applicable in a wide range of devices where muscle-like motion is desirable.

  9. Uncertainty in artificial intelligence

    Kanal, LN

    1986-01-01

    How to deal with uncertainty is a subject of much controversy in Artificial Intelligence. This volume brings together a wide range of perspectives on uncertainty, many of the contributors being the principal proponents in the controversy.Some of the notable issues which emerge from these papers revolve around an interval-based calculus of uncertainty, the Dempster-Shafer Theory, and probability as the best numeric model for uncertainty. There remain strong dissenting opinions not only about probability but even about the utility of any numeric method in this context.

  10. Bayesian artificial intelligence

    Korb, Kevin B

    2010-01-01

    Updated and expanded, Bayesian Artificial Intelligence, Second Edition provides a practical and accessible introduction to the main concepts, foundation, and applications of Bayesian networks. It focuses on both the causal discovery of networks and Bayesian inference procedures. Adopting a causal interpretation of Bayesian networks, the authors discuss the use of Bayesian networks for causal modeling. They also draw on their own applied research to illustrate various applications of the technology.New to the Second EditionNew chapter on Bayesian network classifiersNew section on object-oriente

  11. Mechanism of artificial heart

    Yamane, Takashi

    2016-01-01

    This book first describes medical devices in relation to regenerative medicine before turning to a more specific topic: artificial heart technologies. Not only the pump mechanisms but also the bearing, motor mechanisms, and materials are described, including expert information. Design methods are described to enhance hemocompatibility: main concerns are reduction of blood cell damage and protein break, as well as prevention of blood clotting. Regulatory science from R&D to clinical trials is also discussed to verify the safety and efficacy of the devices.

  12. Low-background shielding of Ge detectors for the measurement of residual 152Eu radioactivity induced by neutrons from the Hiroshima atomic bomb

    Shizuma, Kiyoshi; Fukami, Kenji; Iwatani, Kazuo; Hasai, Hiromi

    1992-05-01

    Low-background gamma-ray spectrometers were constructed for the measurement of residual 152Eu activity induced by the atomic-bomb neutrons. Optimum thickness of lead shielding, inner linings and background characteristics were investigated for an ordinary coaxial- and a well-type Ge detector. In addition, an anticoincidence shielding was installed for the well-type detector. As a result, the background counting rate due to cosmic rays was greatly reduced. It was also shown that a sample preparation to enrich the objective activity and eliminate background activities was important in the case of the 152Eu measurement.

  13. Survey monitoring of environmental radioactivity in Gunsan area

    At Regional Radioactivity Monitoring Station in Kunsan have been measured priodically in 2000 gross beta activities in the airborne dust, fallout, precipitation and tap water and gamma exposure rates. Artificial radionuclide of 137Cs in airborne dust, fallout and precipitation have also been monitored at the station. As a part of environmental radiation/radioactivity distribution survey around Jeon-buk, vegetables, fishes, shellfishes, drinking water (total 33ea) samples were taken from sampling sites which were selected by KINS. We analysis gamma isotope for all. No significant Changes from the previous survey have been found in both beta activities and gamma exposure rates. As the results of analyzig an artificial nuclide concentration in living environmental sample in Jeon-buk are I fee of radiological contaminants

  14. Survey monitoring of environmental radioactivity in Gunsan area

    Kim, Byoung Ho; Ro, Jeong Suk [Kunsan Regional Radioactivity Monitoring Station, Gunsan (Korea, Republic of)

    2002-12-15

    At Regional Radioactivity Monitoring Station in Kunsan have been measured priodically in 2002 gross beta activities in the airborne dust, fallout, precipitation and tap water and gamma exposure rates. Artificial radionuclide of {sup 137}Cs in airborne dust, fallout and precipitation have also been monitored at the station. As a part of environmental radiation/radioactivity distribution survey around Jeon-buk, vegetables, fishes, shellfishes, drinking water (total 33ea) samples were taken from sampling sites which were selected by KINS. We analysis gamma isotope for all. No significant changes from the previous survey have been found in both beta activities and gamma exposure rates. As the results of analyzig an artificial nuclide concentration in living environmental sample in Jeon-buk are fee of radiological contaminants.

  15. Survey monitoring of environmental radioactivity in Gunsan area

    Kim, Byoung Ho; Ro, Jeong Suk [Kunsan Regional Radioactivity Monitoring Station, Gunsan (Korea, Republic of)

    2001-01-15

    At Regional Radioactivity Monitoring Station in Kunsan have been measured priodically in 2000 gross beta activities in the airborne dust, fallout, precipitation and tap water and gamma exposure rates. Artificial radionuclide of {sup 137}Cs in airborne dust, fallout and precipitation have also been monitored at the station. As a part of environmental radiation/radioactivity distribution survey around Jeon-buk, vegetables, fishes, shellfishes, drinking water (total 33ea) samples were taken from sampling sites which were selected by KINS. We analysis gamma isotope for all. No significant Changes from the previous survey have been found in both beta activities and gamma exposure rates. As the results of analyzig an artificial nuclide concentration in living environmental sample in Jeon-buk are I fee of radiological contaminants.

  16. Radioactivity. Mechanisms and applications

    This work tells the discovery of radioactivity, by specifying the respective contributions of Becquerel, Pierre and marie Curie, Rutherford. It explains its mechanisms that begin in the heart of atom and it gives the principal laws. In the different uses are showed how the carbon 14 is a watch for history, to date rocks and solar system, the radioactivity and the spatial system, tracers and isotopic labelled compounds, for nuclear medicine how to make a diagnosis and how to cure, to end by radioactivity at the service of art and industry. (N.C.)

  17. Predisposal Radioactive Waste Management

    Recognition of the importance of the safe management of radioactive waste means that, over the years, many well-established and effective techniques have been developed, and the nuclear industry and governments have gained considerable experience in this field. Minimization of waste is a fundamental principle underpinning the design and operation of all nuclear operations, together with waste reuse and recycling. For the remaining radioactive waste that will be produced, it is essential that there is a well defined plan (called a waste treatment path) to ensure the safe management and ultimately the safe disposal of radioactive waste so as to guarantee the sustainable long term deployment of nuclear technologies

  18. Radioactivity; La radioactivite

    NONE

    2002-07-01

    This pedagogical document presents the origin, effects and uses of radioactivity: where does radioactivity comes from, effects on the body, measurement, protection against radiations, uses in the medical field, in the electric power industry, in the food (ionization, radio-mutagenesis, irradiations) and other industries (radiography, gauges, detectors, irradiations, tracers), and in research activities (dating, preservation of cultural objects). The document ends with some examples of irradiation levels (examples of natural radioactivity, distribution of the various sources of exposure in France). (J.S.)

  19. Radioactive waste disposal

    The current disposal concept for radioactive waste in the FRG was discussed in the framework of this seminar. In addition to this concept for the treatment of radioactive waste also the volume of this waste is indicated. The present state of the two repositories 'Konrad' and 'Gorleben' is explained, as well as the requirements on waste packages for transportation, intermediate and ultimate storage. The final part discusses the conditioning of this radioactive waste and the control of the barrels as regards the observance of the requirements. (orig.)

  20. Artificial Gravity: Effects on Bone Turnover

    Heer, M.; Zwart, S /R.; Baecker, N.; Smith, S. M.

    2007-01-01

    The impact of microgravity on the human body is a significant concern for space travelers. Since mechanical loading is a main reason for bone loss, artificial gravity might be an effective countermeasure to the effects of microgravity. In a 21-day 6 head-down tilt bed rest (HDBR) pilot study carried out by NASA, USA, the utility of artificial gravity (AG) as a countermeasure to immobilization-induced bone loss was tested. Blood and urine were collected before, during, and after bed rest for bone marker determinations. Bone mineral density was determined by DXA and pQCT before and after bed rest. Urinary excretion of bone resorption markers (n-telopeptide and helical peptide) were increased from pre-bed rest, but there was no difference between the control and the AG group. The same was true for serum c-telopeptide measurements. Bone formation markers were affected by bed rest and artificial gravity. While bone-specific alkaline phosphatase tended to be lower in the AG group during bed rest (p = 0.08), PINP, another bone formation marker, was significantly lower in AG subjects than CN before and during bed rest. PINP was lower during bed rest in both groups. For comparison, artificial gravity combined with ergometric exercise was tested in a 14-day HDBR study carried out in Japan (Iwase et al. J Grav Physiol 2004). In that study, an exercise regime combined with AG was able to significantly mitigate the bed rest-induced increase in the bone resorption marker deoxypyridinoline. While further study is required to more clearly differentiate bone and muscle effects, these initial data demonstrate the potential effectiveness of short-radius, intermittent AG as a countermeasure to the bone deconditioning that occurs during bed rest and spaceflight. Future studies will need to optimize not only the AG prescription (intensity and duration), but will likely need to include the use of exercise or other combined treatments.

  1. Low-level radioactivity measurements in an ocean shellfish matrix

    Reference marine biological samples are necessary to test the performance of the analytical methods employed in surveying and monitoring radioactive materials in the sea. The measurement of artificial and natural radionuclide activity concentrations in ocean shellfish material by nondestructive ultra low-level γ-ray spectrometry in an underground laboratory is reported. The material analysed, a composite material made of Irish Sea and White Sea mussel and Japan Sea oyster, was prepared by the National Institute of Standards and Technology (NIST)

  2. Measurement of radioactivity levels and assessment of radioactivity hazards of soil samples in Karaman, Turkey

    In this study, the levels of the natural and artificial radioactivity in soil samples collected from surrounding of Karaman in Turkey were measured. Activity concentrations of the concerned radionuclides were determined by gamma-ray spectrometry using a high-purity germanium detector with a relative efficiency of 40 % at 1.332 MeV. The results obtained for the 238U series (226Ra, 214Pb and 214Bi), 232Th series (228Ac), 40K and fission product 137Cs are discussed. To evaluate the radiological hazard of radioactivity in samples, the radium equivalent activity (Raeq), the absorbed dose rate (D), the annual effective dose and the external (Hex) and internal hazard index (Hin) were calculated and presented in comparison with the data collected from different areas in the world and Turkey. (authors)

  3. CT staging of lung cancer: the role of artificial pneumothorax

    To determine the role of artificially induced pneumothorax in the evaluation of the chest wall and mediastinal invasion in patients with peripheral bronchogenic carcinoma. CT scans of 22 patients obtained after induced pneumothorax were evaluated. All patients had peripheral lung mass abutting the pleura on a routine CT scan. Room air of 200-400ml was introduced through intrathoracic negative pressure initially, followed by pressure injection through the 18 gauge long bevelled needle under fluoroscopic control. Conclusively, CT with artificial pneumothorax added more information than conventional CT in the evaluation of the chest wall or mediastinal invasion by lung cancer without notable risk

  4. Effect of vanadium treatment on tissue distribution of biotrace elements in normal and streptozotocin-induced diabetic rats. Simultaneous analysis of V and Zn using radioactive multitracer

    Because vanadium ions such as vanadyl (VO2+) and vanadate (VO3-) ions were demonstrated to normalize blood glucose levels of diabetic animals and patients, the action mechanism of vanadium treatment has been of interest. In this study, we focused on understanding interactions among trace elements in diabetic rats, in which a multitracer technique was used. The effects of vanadyl sulfate (VS)-treatment on the tissue distribution of trace vanadium (48V) and zinc (65Zn) in normal and streptozotocin (STZ)-induced diabetic rats were examined, and were evaluated in terms of the uptake ratio. The uptake ratio of both elements in tissues significantly changed between STZ-rats and those treated with VS. These results indicated that vanadium treatment in STZ-rats alters the tissue distribution of endogenous elements, suggesting the importance of the relationship between biotrace elements and pathophysiology. (author)

  5. Understanding radioactive waste

    Murray, R.L.

    1981-12-01

    This document contains information on all aspects of radioactive wastes. Facts are presented about radioactive wastes simply, clearly and in an unbiased manner which makes the information readily accessible to the interested public. The contents are as follows: questions and concerns about wastes; atoms and chemistry; radioactivity; kinds of radiation; biological effects of radiation; radiation standards and protection; fission and fission products; the Manhattan Project; defense and development; uses of isotopes and radiation; classification of wastes; spent fuels from nuclear reactors; storage of spent fuel; reprocessing, recycling, and resources; uranium mill tailings; low-level wastes; transportation; methods of handling high-level nuclear wastes; project salt vault; multiple barrier approach; research on waste isolation; legal requiremnts; the national waste management program; societal aspects of radioactive wastes; perspectives; glossary; appendix A (scientific American articles); appendix B (reference material on wastes). (ATT)

  6. Radioactive wastes and discharges

    According to the Section 24 of the Finnish Radiation Decree (1512/91), the Finnish Centre for Radiation and Nuclear Safety shall specify the concentration and activity limits and principles for the determination whether a waste can be defined as a radioactive waste or not. The radiation safety requirements and limits for the disposal of radioactive waste are given in the guide. They must be observed when discharging radioactive waste into the atmosphere or sewer system, or when delivering solid low-activity waste to a landfill site without a separate waste disposal plan. The guide does not apply to the radioactive waste resulting from the utilization of nuclear energy of natural resources. (4 refs., 1 tab.)

  7. Understanding radioactive waste

    This document contains information on all aspects of radioactive wastes. Facts are presented about radioactive wastes simply, clearly and in an unbiased manner which makes the information readily accessible to the interested public. The contents are as follows: questions and concerns about wastes; atoms and chemistry; radioactivity; kinds of radiation; biological effects of radiation; radiation standards and protection; fission and fission products; the Manhattan Project; defense and development; uses of isotopes and radiation; classification of wastes; spent fuels from nuclear reactors; storage of spent fuel; reprocessing, recycling, and resources; uranium mill tailings; low-level wastes; transportation; methods of handling high-level nuclear wastes; project salt vault; multiple barrier approach; research on waste isolation; legal requiremnts; the national waste management program; societal aspects of radioactive wastes; perspectives; glossary; appendix A (scientific American articles); appendix B (reference material on wastes)

  8. Radioactive waste management

    This chapter discussed the basic subjects covered in the radioactive waste management. The subjects are policy and legislation, pre-treatment, classification, segregation, treatment, conditioning, storage, siting and disposal, and quality assurance

  9. Radioactivity in environmental samples

    The objective of this practical work is to familiarize the student with radioactivity measures in environmental samples. For that were chosen samples a salt of natural potassium, a salt of uranium or torio and a sample of drinkable water

  10. Law of radioactive minerals

    Legal device done in order to standardize and promote the exploration and explotation of radioactive minerals by peruvian and foreign investors. This device include the whole process, since the prospection until the development, after previous auction given by IPEN

  11. Classification of radioactive waste

    Radioactive wastes are generated in a number of different kinds of facilities and arise in a wide range of concentrations of radioactive materials and in a variety of physical and chemical forms. To simplify their management, a number of schemes have evolved for classifying radioactive waste according to the physical, chemical and radiological properties of significance to those facilities managing this waste. These schemes have led to a variety of terminologies, differing from country to country and even between facilities in the same country. This situation makes it difficult for those concerned to communicate with one another regarding waste management practices. This document revises and updates earlier IAEA references on radioactive waste classification systems given in IAEA Technical Reports Series and Safety Series. Guidance regarding exemption of materials from regulatory control is consistent with IAEA Safety Series and the RADWASS documents published under IAEA Safety Series. 11 refs, 2 figs, 2 tab

  12. Environmental radioactivity surveillance programme 1999 and 2000

    The Radiological Protection Institute of Ireland continued to monitor levels of radioactivity in air, drinking water and foodstuffs in 1999 and 2000 and the results are presented in this report, the sixth in a series dealing with the terrestrial environment. Radioactivity is present in the terrestrial environment due to natural processes, the testing of nuclear weapons in the atmosphere, accidents such as the Chernobyl accident and the routine discharge of radionuclides from nuclear installations. The Institute monitored airborne radioactivity at ten stations throughout the country. One site was equipped to detect the presence of krypton-85, a radionuclide which is released into the environment primarily as a result of the reprocessing of nuclear fuel at installations such as Sellafield in the UK and La Hague in France. Both in 1999 and 2000, levels of radionuclides in airborne particulates were low and consistent with measurements in previous years. Public water supplies are sampled from each county at least every four years with supplies to certain major population centres sampled annually. Water supplies from eleven counties were sampled between 1999 and 2000 and all of the waters tested were found to be within legal requirements for water quality from a radiological point of view. The levels of artificial radioactivity in milk and other foodstuffs such as milk products, baby foods, beef, lamb, poultry and vegetables continued to be very low in 1999 and 2000 and, for the majority of samples, below the detection limits. External gamma dose rates were monitored continuously at twelve locations around the country. The dose rate was recorded every twenty minutes and the readings transmitted automatically to the Institute's computer database at Clonskeagh (Dublin). No abnormally high levels were observed at any of the twelve stations in either 1999 or 2000. The data presented in this report demonstrate that the levels of artificial radioactivity in the Irish

  13. Artificial organs: recent progress in artificial hearing and vision.

    Ifukube, Tohru

    2009-01-01

    Artificial sensory organs are a prosthetic means of sending visual or auditory information to the brain by electrical stimulation of the optic or auditory nerves to assist visually impaired or hearing-impaired people. However, clinical application of artificial sensory organs, except for cochlear implants, is still a trial-and-error process. This is because how and where the information transmitted to the brain is processed is still unknown, and also because changes in brain function (plasticity) remain unknown, even though brain plasticity plays an important role in meaningful interpretation of new sensory stimuli. This article discusses some basic unresolved issues and potential solutions in the development of artificial sensory organs such as cochlear implants, brainstem implants, artificial vision, and artificial retinas. PMID:19330498

  14. Temporary Personal Radioactivity

    Myers, Fred

    2012-01-01

    As part of a bone scan procedure to look for the spread of prostate cancer, I was injected with radioactive technetium. In an effort to occupy/distract my mind, I used a Geiger counter to determine if the radioactive count obeyed the inverse-square law as a sensor was moved away from my bladder by incremental distances. (Contains 1 table and 2…

  15. Radioactive substances and man

    The distribution and excretion of radioactive substances after their inhalation, peroral and throughskin intake into the organism are considered. Data on the basis of the biological effect of radionuclides including the development of acute, subacute and delayed effects are presented; the levels of natural and technogenic backgrounds on the Earth planet are considered in this case. The most perspective preventive and protective measures against radioactive substances intake are discussed. 77 refs.; 12 figs.; 74 tabs

  16. Dynamic radioactive particle source

    Moore, Murray E.; Gauss, Adam Benjamin; Justus, Alan Lawrence

    2012-06-26

    A method and apparatus for providing a timed, synchronized dynamic alpha or beta particle source for testing the response of continuous air monitors (CAMs) for airborne alpha or beta emitters is provided. The method includes providing a radioactive source; placing the radioactive source inside the detection volume of a CAM; and introducing an alpha or beta-emitting isotope while the CAM is in a normal functioning mode.

  17. Transport of radioactive materials

    The purpose of this Norm is to establish, relating to the TRANSPORT OF RADIOACTIVE MATERIALS, safety and radiological protection requirements to ensure an adequate control level of the eventual exposure of persons, properties and environment to the ionizing radiation comprising: specifications on radioactive materials for transport; package type selection; specification of the package design and acceptance test requirements; arrangements relating to the transport itself; administrative requirements and responsibilities. (author)

  18. Radioactive waste management

    This book highlights the main issues of public concern related to radioactive waste management and puts them into perspective. It provides an overview of radioactive waste management covering, among other themes, policies, implementation and public communication based on national experiences. Its purpose is to assists in increasing the understanding of radioactive waste management issues by public and national authorities, organizations involved in radioactive waste management and the nuclear industry; it may also serve as a source book for those who communicate with the public. Even in the unlikely event that nuclear power does not further develop around the world, the necessity for dealing with nuclear waste from past usages, from uranium mining and milling, decontamination and decommissioning of existing nuclear facilities and from the uses of radioactive materials in medicine, industry and research would still exist. In many countries, radioactive waste management planning involves making effective institutional arrangements in which responsibilities and liabilities are well established for the technical operation and long term surveillance of disposal systems. Financing mechanisms are part of the arrangements. Continuous quality assurance and quality control, at all levels of radioactive waste management, are essential to ensure the required integrity of the system. As with any other human activity, improvements in technology and economics may be possible and secondary problems avoided. Improvements and confirmation of the efficiency of processes and reduction of uncertainties can only be achieved by continued active research, development and demonstration, which are the goals of many national programmes. International co-operation, also in the form of reviews, can contribute to increasing confidence in the ongoing work. The problem of radioactive wastes is not a unique one; it may be compared with other problems of toxic wastes resulting from many other

  19. Two-proton radioactivity

    Blank, Bertram; Ploszajczak, Marek

    2007-01-01

    In the first part of the present review paper, experimental results which lead to the discovery of two-proton radioactivity are reviewed. Beyond two-proton emission from nuclear ground states, we also discuss experimental studies of two-proton emission from excited states populated either by nuclear beta decay or by inelastic reactions. In the second part, we review the modern theory of two-proton radioactivity. An outlook to future experimental studies and theoretical developments will concl...

  20. Radioactive waste disposal policy

    The responsibilities of the Minister of Agriculture, Fisheries and Food and Ministry policy on radioactive waste disposal are described. The disposal of solid radioactive waste at sea is subject to detailed safeguards developed within two international agreements to which the United Kingdom is a contracting party. The agreements are discussed together with a research and monitoring programme to provide scientific data for informed decisions on waste disposal authorisations and dumping licences. (U.K.)

  1. Radioactive sources service

    2006-01-01

    Dear Users, A new web interface is now available for requesting radioactive sources: http://cern.ch/rp-sources/request This link is also available from the radioactive sources service main page: http://cern.ch/rp-sources From now on, please submit your request via the above interface, which has been developed in order to improve the service. Thank you in advance for your collaboration!

  2. Environmental radioactivity monitoring for radiation protection

    The present research was conducted in the frame of a program of routine radioactivity surveillance around the Thai Research Reactor (TRR-1) as well as for the investigation of contamination due to nuclear weapons tests. Samples of air, water, fallout, soil, grass, vegetables, seafood, fish, and meat were collected from five stations throughout the country and measured for gross alpha, beta, and gamma radioactivity and for Cs-137 and K-40 concentration. The methods used were the standard oneswell established in routine laboratory practice. Cumulative annual radiation dose from natural gamma radiation exposure of the population was also measured by TLD LiF dosemeters. Indoor and outdoor exposures were also compared. Results indicate that the gross radioactivity and the concentration of Cs-137 and K-40 in environmental samples do not exceed values considered normal. The average cumulative annual radiation dose from natural gamma radiation during the period 1978-1980 was 80.4+-27 mrem. Comparison between in- and outdoor doses showed that the latter are higher in the two (out of five) locations where the data were available. No indication is given on the type of building material used in the areas under examination, whether wood or any other traditional material of natural or artificial origin

  3. Literature in focus: The history of radioactivity

    2006-01-01

    René Bimbot, an expert in nuclear physics, will be coming to present his book - The History of Radioactivity. The work provides a summary of our accumulated knowledge of radioactivity and its applications, from its discovery to the present day. Presented in layman's terms, and backed by plenty of illustrations, the work creates the link between the rudimentary knowledge available in the times of Becquerel and the Curies and contemporary physics. It takes us on a great physics adventure, from the nucleus to the quark, from artificial radioactivity to radiotherapy, from the discovery of fission to nuclear reactors, not forgetting dating methods. Finally, the work provides a wealth of practical information on radiation and on matters relating to nuclear waste. A former Research Director at the CNRS, a heavy-ion physicist at the Orsay Nuclear Physics Institute, René Bimbot is no stranger to CERN. At the beginning of the 1980s, he worked on the CERN Synchrocyclotron, before joining the GANIL experiment in 1985...

  4. Environmental radioactivity at Machu Picchu Scientific Station

    Studies on environmental radioactivity at the Peruvian Scientific Station were carried out in the last two austral summer periods. The main objective of this study is to establish an environmental radiological monitoring program for evaluating environmental components and achieving a baseline study related to artificial and natural radioactivity levels. For this purpose, samples such as seaweeds, mosses, lichens, soil seawater, ice, marine sediment and underground water were collected from the area surrounding the station starting from Punta Crepin to Playa Inca and Playa Naylamp; then they were pre-conditioned in Machu Picchu Station and were sent to the Environmental Radioactivity laboratory of 'Racso' Peruvian Nuclear Center to conduct beta and gamma spectrometry. The Obtained results showed the presence of Cs-137 in geological components (soil and sediment) and in biological components (lichens and mosses). Nevertheless, those levels seem to be in a range of normal fluctuations after atmospheric nuclear testing and they are not considered to be dangerous to the ecosystem of the Antarctic Region. On the other hand, high concentration of Be-7 has been detected in seaweed and lichens. Other natural radionuclide detected were Ra-226, Bi-214 and K-40

  5. Natural and artificial radionuclides in seabed sediments of Hong Kong

    A new nuclear reactor has been built in the Daya Bay which is very near to the densely populated Hong Kong area. It has been estimated that the annual, direct discharge of low level radioactive waste water from each reactor module into the Daya Bay could reach 3 Ci. This radioactive waste will follow the coastal current and enter the sea areas around Hong Kong, and may cause an elevation in the radioactivity levels of both sea water and sediments. In order to assess the effects of the reactor on the Hong Kong aquatic environment, it is important to know the baseline value, or the background level of the natural and artificial radionuclides before the operation of the reactor. This paper reports the natural and artificial radionuclide contents in seabed surface sediments collected from 8 sampling sites in the southern and eastern sea areas of Hong Kong, which have been analysed by using a high purity germanium γ-ray spectrometer. The U-238, Ra-226, Th-232 and K-40 concentrations were respectively 44.1, 32.5, 48.1 and 625 Bq/kg and the variations in different sites were not significant. The mean concentration for Cs-137 is 2.00 Bq/kg, with the mean value for the southern sea area higher than that for the eastern sea area. (author)

  6. Radioactive dust sampling

    This technical report is the second of a five part series on the technical evaluation of a number of dust monitoring instruments and the characterization of Long-Lived Radioactive Dust (LLRD). The data reported here pertain to an experimental study conducted under laboratory controlled conditions in a Long-Lived Radioactive Dust Test Facility (LLRDTF) designed for this purpose. This study was carried out with a twofold purpose in mind, namely, for the characterization of dust and LLRD, and for the evaluation of a variety of monitoring instruments, including cascade impactors, optical particle counters, nylon cyclones, open face filter samplers, and α-particle personal dosimeters, the latter normally used for α-particle radiation exposure purposes. Several non-radioactive and radioactive dusts were characterized. The non-radioactive dusts were SiC, Al2O3, talcum powder, corn starch and flour, while uranium tailings were used as a radioactive dust. Clear differences in instrument performance were observed for the various measurements made

  7. Environmental radioactivity at the Peruvian Scientific Station Machu Picchu 1999 - 2000 Antarctic region

    The Peruvian Institute of Nuclear Energy (IPEN) initiated the Environmental Radioactivity studies in the Antarctic Region in 1996. The objective of this research was to determine the levels of natural and artificial radioactivity achieving the evaluation of the radiological status in the antarctic region. Samples of brown algae (phaeophyta), lichens, moss, gramineous, soil, marine sediment, sea water and air were collected in the surrounding area of the Machu Picchu Scientific Station. This study shows the results corresponding to the 1999-2000 period

  8. Artificial sweeteners - a review.

    Chattopadhyay, Sanchari; Raychaudhuri, Utpal; Chakraborty, Runu

    2014-04-01

    Now a days sugar free food are very much popular because of their less calorie content. So food industry uses various artificial sweeteners which are low in calorie content instead of high calorie sugar. U.S. Food and Drug Administration has approved aspartame, acesulfame-k, neotame, cyclamate and alitame for use as per acceptable daily intake (ADI) value. But till date, breakdown products of these sweeteners have controversial health and metabolic effects. On the other hand, rare sugars are monosaccharides and have no known health effects because it does not metabolize in our body, but shows same sweet taste and bulk property as sugar. Rare sugars have no such ADI value and are mainly produced by using bioreactor and so inspite of high demand, rare sugars cannot be produced in the desired quantities. PMID:24741154

  9. Artificial Immune Systems (2010)

    Greensmith, Julie; Aickelin, Uwe

    2010-01-01

    The human immune system has numerous properties that make it ripe for exploitation in the computational domain, such as robustness and fault tolerance, and many different algorithms, collectively termed Artificial Immune Systems (AIS), have been inspired by it. Two generations of AIS are currently in use, with the first generation relying on simplified immune models and the second generation utilising interdisciplinary collaboration to develop a deeper understanding of the immune system and hence produce more complex models. Both generations of algorithms have been successfully applied to a variety of problems, including anomaly detection, pattern recognition, optimisation and robotics. In this chapter an overview of AIS is presented, its evolution is discussed, and it is shown that the diversification of the field is linked to the diversity of the immune system itself, leading to a number of algorithms as opposed to one archetypal system. Two case studies are also presented to help provide insight into the m...

  10. Natural occurring radioactive substances. Vol. 1

    Naturally occurring radioactive substances produced by cosmic rays of those of terrestrial origin are surveyed. The different radioactive decay series are discussed. Special emphasis is given to the element radium as regards its properties and distribution in different environmental samples. The properties of naturally occurring k-40 and its distribution in different natural media are also outlined. Induced radionuclides which are formed as a result of the interaction of cosmic rays with the constituents of the atmosphere are mentioned. In this respect the intensity of natural background radiation and the dose at different locations and levels is surveyed. Some regions of exceptionally high radioactivity which result in high exposure rates are mentioned. Monazite deposits and water springs are mentioned in some detail. The Oklo phenomenon as a natural reactor is also discussed. 8 tabs

  11. A Primer on Artificial Intelligence.

    Leal, Ralph A.

    A survey of literature on recent advances in the field of artificial intelligence provides a comprehensive introduction to this field for the non-technical reader. Important areas covered are: (1) definitions, (2) the brain and thinking, (3) heuristic search, and (4) programing languages used in the research of artificial intelligence. Some…

  12. Generalized Adaptive Artificial Neural Networks

    Tawel, Raoul

    1993-01-01

    Mathematical model of supervised learning by artificial neural network provides for simultaneous adjustments of both temperatures of neurons and synaptic weights, and includes feedback as well as feedforward synaptic connections. Extension of mathematical model described in "Adaptive Neurons For Artificial Neural Networks" (NPO-17803). Dynamics of neural network represented in new model by less-restrictive continuous formalism.

  13. Sucrose compared with artificial sweeteners

    Sørensen, Lone Brinkmann; Vasilaras, Tatjana H; Astrup, Arne;

    2014-01-01

    There is a lack of appetite studies in free-living subjects supplying the habitual diet with either sucrose or artificially sweetened beverages and foods. Furthermore, the focus of artificial sweeteners has only been on the energy intake (EI) side of the energy-balance equation. The data are from a...

  14. Development of an experimental set-up for the measurement of neutron-induced fission and capture cross sections of highly radioactive fissile nuclei

    Companis Iulia

    2014-04-01

    Full Text Available The measurement of neutron-capture cross sections of many actinides is complicated by the difficulty in separating capture γ-rays from the large fission-fragment prompt γ-ray background. For example, current estimates of the capture cross section of 233U show large discrepancies, with differences of more than 20%. To improve the accuracy of data, a new experimental set-up for the simultaneous measurement of the neutron-induced capture and fission cross sections was designed, assembled and optimized. The measurements will be performed at the GEel LINear Accelerator (GELINA neutron time-of-flight facility in Belgium, where neutron cross sections can be measured over a wide energy range with high energy resolution. The fission detector consists of a dedicated multi-plate high-efficiency ionization chamber (IC. The γ-rays produced in capture reaction are detected by an array of C6D6 scintillators. Fission γ–rays are distinguished from capture γ–rays by the anticoincidence signals from the IC and the C6D6 detectors. For the undetected fission events a correction has to be applied based on the efficiency of the IC that should be high and known with a high accuracy. The performance of the IC during dedicated test experiments is presented, focusing on the determination of the detection efficiency.

  15. Development of an experimental set-up for the measurement of neutron-induced fission and capture cross sections of radioactive fissile nuclei

    Companis I.

    2013-12-01

    Full Text Available A new experimental set-up for a simultaneous measurement of neutron induced capture and fission cross sections was designed, assembled and optimized. The measurements will be performed at GEel LINear Accelerator (GELINA neutron time-of-flight facility in Belgium, where neutron cross sections can be measured over a wide energy range with high energy resolution. The fission events detector consists of a dedicated multi-plate high efficiency fission ionization chamber (IC. The γ-rays produced in capture reaction are detected by an efficient array of C6D6 scintillators. Fission γ-rays events are distinguished from capture events by the anticoincidence signals from the IC and the C6D6 detectors. For the undetected fission events a correction has to be applied with respect to the efficiency of the IC that should be high and known with a high precision. Another important issue is the good separation between fission-fragment (FF and the high alpha pile-up. The performances of the IC during test experiments are presented, focusing in particular on the detection efficiency.

  16. Development of an experimental set-up for the measurement of neutron-induced fission and capture cross sections of highly radioactive fissile nuclei

    Companis, Iulia; Mathieu, Ludovic; Aïche, Mourad; Schillebeeckx, Peter; Heyse, Jan; Barreau, Gérard; Czajkowski, Serge; Ducasse, Quentin; Gunsing, Frank; Jurado, Beatriz; Kessedjian, Gregoire; Matarranz, Julie; Tsekhanovich, Igor

    2014-04-01

    The measurement of neutron-capture cross sections of many actinides is complicated by the difficulty in separating capture γ-rays from the large fission-fragment prompt γ-ray background. For example, current estimates of the capture cross section of 233U show large discrepancies, with differences of more than 20%. To improve the accuracy of data, a new experimental set-up for the simultaneous measurement of the neutron-induced capture and fission cross sections was designed, assembled and optimized. The measurements will be performed at the GEel LINear Accelerator (GELINA) neutron time-of-flight facility in Belgium, where neutron cross sections can be measured over a wide energy range with high energy resolution. The fission detector consists of a dedicated multi-plate high-efficiency ionization chamber (IC). The γ-rays produced in capture reaction are detected by an array of C6D6 scintillators. Fission γ-rays are distinguished from capture γ-rays by the anticoincidence signals from the IC and the C6D6 detectors. For the undetected fission events a correction has to be applied based on the efficiency of the IC that should be high and known with a high accuracy. The performance of the IC during dedicated test experiments is presented, focusing on the determination of the detection efficiency.

  17. Development of an experimental set-up for the measurement of neutron-induced fission and capture cross sections of radioactive fissile nuclei

    Companis, I.; Aïche, M.; Mathieu, L.; Schillebeeckx, P.; Heyse, J.; Barreau, G.; Czajkowski, S.; Ducasse, Q.; Gunsing, F.; Jurado, B.; Kessedjian, G.; Matarranz, J.; Plompen, A. J. M.; Tsekhanovich, I.

    2013-12-01

    A new experimental set-up for a simultaneous measurement of neutron induced capture and fission cross sections was designed, assembled and optimized. The measurements will be performed at GEel LINear Accelerator (GELINA) neutron time-of-flight facility in Belgium, where neutron cross sections can be measured over a wide energy range with high energy resolution. The fission events detector consists of a dedicated multi-plate high efficiency fission ionization chamber (IC). The γ-rays produced in capture reaction are detected by an efficient array of C6D6 scintillators. Fission γ-rays events are distinguished from capture events by the anticoincidence signals from the IC and the C6D6 detectors. For the undetected fission events a correction has to be applied with respect to the efficiency of the IC that should be high and known with a high precision. Another important issue is the good separation between fission-fragment (FF) and the high alpha pile-up. The performances of the IC during test experiments are presented, focusing in particular on the detection efficiency.

  18. Development of an experimental set-up for the measurement of neutron-induced fission and capture cross sections of highly radioactive fissile nuclei

    The measurement of neutron-capture cross sections of many actinides is complicated by the difficulty in separating capture γ-rays from the large fission-fragment prompt γ-ray background. For example, current estimates of the capture cross section of 233U show large discrepancies, with differences of more than 20%. To improve the accuracy of data, a new experimental set-up for the simultaneous measurement of the neutron-induced capture and fission cross sections was designed, assembled and optimized. The measurements will be performed at the GEel LINear Accelerator (GELINA) neutron time-of-flight facility in Belgium, where neutron cross sections can be measured over a wide energy range with high energy resolution. The fission detector consists of a dedicated multi-plate high-efficiency ionization chamber (IC). The γ-rays produced in capture reaction are detected by an array of C6D6 scintillators. Fission γ-rays are distinguished from capture γ-rays by the anticoincidence signals from the IC and the C6D6 detectors. For the undetected fission events a correction has to be applied based on the efficiency of the IC that should be high and known with a high accuracy. The performance of the IC during dedicated test experiments is presented, focusing on the determination of the detection efficiency. (author)

  19. Development of an experimental set-up for the measurement of neutron-induced fission and capture cross sections of radioactive fissile nuclei

    A new experimental set-up for a simultaneous measurement of neutron induced capture and fission cross sections was designed, assembled and optimized. The measurements will be performed at Geel Linear Accelerator (GELINA) neutron time-of-flight facility in Belgium, where neutron cross sections can be measured over a wide energy range with high energy resolution. The fission events detector consists of a dedicated multi-plate high efficiency fission ionization chamber (IC). The γ-rays produced in capture reaction are detected by an efficient array of C6D6 scintillators. Fission γ-rays events are distinguished from capture events by the anticoincidence signals from the IC and the C6D6 detectors. For the undetected fission events a correction has to be applied with respect to the efficiency of the IC that should be high and known with a high precision. Another important issue is the good separation between fission-fragment (FF) and the high alpha pile-up. The performances of the IC during test experiments are presented, focusing in particular on the detection efficiency. (authors)

  20. Soft computing in artificial intelligence

    Matson, Eric

    2014-01-01

    This book explores the concept of artificial intelligence based on knowledge-based algorithms. Given the current hardware and software technologies and artificial intelligence theories, we can think of how efficient to provide a solution, how best to implement a model and how successful to achieve it. This edition provides readers with the most recent progress and novel solutions in artificial intelligence. This book aims at presenting the research results and solutions of applications in relevance with artificial intelligence technologies. We propose to researchers and practitioners some methods to advance the intelligent systems and apply artificial intelligence to specific or general purpose. This book consists of 13 contributions that feature fuzzy (r, s)-minimal pre- and β-open sets, handling big coocurrence matrices, Xie-Beni-type fuzzy cluster validation, fuzzy c-regression models, combination of genetic algorithm and ant colony optimization, building expert system, fuzzy logic and neural network, ind...

  1. Beyond AI: Artificial Dreams Conference

    Zackova, Eva; Kelemen, Jozef; Beyond Artificial Intelligence : The Disappearing Human-Machine Divide

    2015-01-01

    This book is an edited collection of chapters based on the papers presented at the conference “Beyond AI: Artificial Dreams” held in Pilsen in November 2012. The aim of the conference was to question deep-rooted ideas of artificial intelligence and cast critical reflection on methods standing at its foundations.  Artificial Dreams epitomize our controversial quest for non-biological intelligence, and therefore the contributors of this book tried to fully exploit such a controversy in their respective chapters, which resulted in an interdisciplinary dialogue between experts from engineering, natural sciences and humanities.   While pursuing the Artificial Dreams, it has become clear that it is still more and more difficult to draw a clear divide between human and machine. And therefore this book tries to portrait such an image of what lies beyond artificial intelligence: we can see the disappearing human-machine divide, a very important phenomenon of nowadays technological society, the phenomenon which i...

  2. Genetic effects from environmental radioactive contamination for natural populations of plants and animals

    At the present time the genetic effects from environmental radioactive contamination for natural populations of plants and animals are becoming particularly important issue. This is caused by the real existing situation of irradiation of natural communities on the sites of nuclear testing and uranium mining in the zone of influence of industrial enterprises of the Republic of Kazakhstan. Results obtained in studies of plants and animals allow indirectly evaluate the risk of manifestation of defects in humans. Studying the reaction of a population of organisms that are in their natural habitat to the chronic effect of ionizing radiation is of great interest in terms of environmental regulation of artificial radionuclides content in the external environment. Such regulations, along with radiation-hygienic characteristics are important in regulating the use of nuclear energy for peaceful purposes. As a subject of study we've selected wild plant species - Agropyron castorem L., Festuca valesiace Gaudin, Stipa sareptana Beck, Artemisia gracilescens Krach, growing in areas with different levels (high, medium, background) of radionuclide contamination at 'Balapan' site, as well as rodents - Citellus erythrogenus Brandt, Allactaga saltator Ewersm, Allactaga major Kerr, inhabiting in similar areas of the site. Analysis of the spectrum of chromosome aberrations of plants was carried out by the standard technique, determination of genetic damage in germ and somatic cells of animals with 2 express-methods: counting of abnormal sperm heads and micronucleus test - cytogenetic analysis of peripheral blood erythrocytes of animals. It is shown that in natural populations of the studied plants grown in radioactively contaminated sectors of technical ground 'Balapan' at the former STS significantly higher yield of induced chromosomal mutations was found. We revealed that in natural populations of three species of studied rodents inhabiting the radioactively contaminated territories

  3. X rays and radioactivity: a complete surprise

    The discoveries of X rays and of radioactivity came as complete experimental surprises; the physicists, at that time, had no previous hint of a possible structure of atoms. It is difficult now, knowing what we know, to replace ourselves in the spirit, astonishment and questioning of these years, between 1895 and 1903. The nature of X rays was soon hypothesized, but the nature of the rays emitted by uranium, polonium and radium was much more difficult to disentangle, as they were a mixture of different types of radiations. The origin of the energy continuously released in radioactivity remained a complete mystery for a few years. The multiplicity of the radioactive substances became soon a difficult matter: what was real and what was induced ? Isotopy was still far ahead. It appeared that some radioactive substances had ''half-lifes'': were they genuine radioactive elements or was it just a transitory phenomenon ? Henri Becquerel (in 1900) and Pierre and Marie Curie (in 1902) hesitated on the correct answer. Only after Ernest Rutherford and Frederick Soddy established that radioactivity was the transmutation of one element into another, could one understand that a solid element transformed into a gaseous element, which in turn transformed itself into a succession of solid radioactive elements. It was only in 1913 - after the discovery of the atomic nucleus -, through precise measurements of X ray spectra, that Henry Moseley showed that the number of electrons of a given atom - and the charge of its nucleus - was equal to its atomic number in the periodic table. (authors)

  4. Artificial patinas analyzed with PIXE method

    Aiming at the restoration and conservation of the archaeological metallic objects, the artificial patinas can be used to simulate the natural patinas (corrosion products in metal and its alloys), permitting the characterization and corrosion mechanisms studies. The natural patinas formation is difficult to study because of the long corrosion production process in materials which take years to be formed. On the other hand the artificial patinas can be easily produced in a shorter time, moreover, they can be used as simulation of the corrosion process and in substitution of monuments and old art objects, damaged for some reason. In our study artificial patinas were produced over pellets of copper and bronze with sulfate, chloride and nitrate solutions and were analyzed with PIXE (Proton Induced X-Ray Emission) technique to supply qualitative and quantitative information of the corrosion elements. The quantitative PIXE analysis takes into account the incident ion beam absorption and the emergent X-ray of the sample, as well as the patina layer and the backing. The PIXE results have shown the presence of S, Cl and Fe and some other elements already known form the backings, such as Cu, Sn, etc. PIXE measurements were also realized in reference metallic materials. (author)

  5. AKTIS Nr. 12: To better understand radioactive aerosol deposit in order to better measure it; Radio-induced lesions: a new step towards healing; Modelling the collapse of an immersed grain column; To better model soot deposit; Towards the prediction of the leakage rate of containment enclosures

    This publication presents the main results of researches undertaken by the IRSN in the field of radiation protection, nuclear safety and security. The topics herein addressed are: radio-induced lesions as a new step towards healing (case of injection mesenchymal stem cells for the treatment of induced severe colorectal lesions), the modelling of the collapse of an immersed grain column (to study the nuclear fuel behaviour in an accidental situation through a modelling of fluid-grain interactions), a better understanding of radioactive aerosol deposit (to study particle or aerosol deposits after radioactive releases in the atmosphere in case of accident), a better modelling of soot deposits (in case of fire), the prediction of leakage rates of containment enclosures (ageing phenomena of installations, systems and equipment, with the case of cracks due to material ageing and resulting in confinement losses which could thus be quantified)

  6. Pressurized liquid extraction-gas chromatography-mass spectrometry for confirming the photo-induced generation of dioxin-like derivatives and other cosmetic preservative photoproducts on artificial skin.

    Alvarez-Rivera, Gerardo; Llompart, Maria; Garcia-Jares, Carmen; Lores, Marta

    2016-04-01

    The stability and photochemical transformations of cosmetic preservatives in topical applications exposed to UV-light is a serious but poorly understood problem. In this study, a high throughput extraction and selective method based on pressurized liquid extraction (PLE) coupled to gas chromatography-mass spectrometry (GC-MS) was validated and applied to investigate the photochemical transformation of the antioxidant butylated hydroxytoluene (BHT), as well as the antimicrobials triclosan (TCS) and phenyl benzoate (PhBz) in an artificial skin model. Two sets of photodegradation experiments were performed: (i) UV-Irradiation (8W, 254nm) of artificial skin directly spiked with the target preservatives, and (ii) UV-irradiation of artificial skin after the application of a cosmetic cream fortified with the target compounds. After irradiation, PLE was used to isolate the target preservatives and their transformation products. The follow-up of the photodegradation kinetics of the parent preservatives, the identification of the arising by-products, and the monitorization of their kinetic profiles was performed by GC-MS. The photochemical transformation of triclosan into 2,8-dichloro-dibenzo-p-dioxin (2,8-DCDD) and other dioxin-like photoproducts has been confirmed in this work. Furthermore, seven BHT photoproducts, and three benzophenones as PhBz by-products, have been also identified. These findings reveal the first evidences of cosmetic ingredients phototransformation into unwanted photoproducts on an artificial skin model. PMID:26948762

  7. Study of radio-active ions in the atmosphere

    A comparative study is made of active, deposits of radon and thoron in suspension in the atmosphere by means of α radiation counting, using ZELENY tubes, scattering equipment, filter papers or membranes. It has been possible to show the existence of small and large ions which are negative and positive, as well as of neutral radio-active nuclei; their properties are studied. A theoretical interpretation of the results is presented. The average content of radon (using the Ra A concentration) and of Th B in the air has been determined. The radioactive equilibrium between radon and its daughter products in atmospheric air are examined. The techniques developed for active radon and thoron deposits are applied to the study of artificial radio-activity, the analyses being carried out by means of γ spectrometry. (author)

  8. Survey monitoring of environmental radioactivity in Daegu area

    Kang, Hee Dong; Lee, Hae Young; Yang, Chan Sun [Kyungpook National Univ., Daegu (Korea, Republic of)

    2001-12-15

    The objectives of the project are to monitor an abnormal radiation level in Taegu and Kyungpook region, and to enhance our ability to prepare for the radiological emergency situation by establishing the radioactivity monitoring system in Taegu and Kyungpook region. In this report, we summarized a gamma exposure rates, a gross beta and gamma radionuclide activities for the environmental samples of airborned-dust. precipitation, fallout and tap water collected in Taegu radioactivity monitoring center, and a gamma radionuclide activities for the 28 grocery samples, such as tea, nut and mushroom, rice, chinese cabbage, wormwood and pine needles, soil and drinking water which were obtained from Taegu and Kyungpook region to establish the basic data base for estimating the internal exposure. In conclusion, it didn't appear any evidence for newly pollution of artificial radioactivity in Taegu and Kyungpook region.

  9. Management on radioactive wastes

    The basic philosophy governing the radioactive waste management activities in India is to concentrate and contain as much activity as possible and to discharge to the environment only such of these streams that have radioactive content much below the nationally and internationally accepted standards. The concept of ''Zero Release'' is also kept in view. At Tarapur, the effluents are discharged into coastal waters after the radioactivity of the effluents is brought down by a factor 100. The effluents fΩm Rajasthan reactors are discharged into a lake keeping their radioactivity well within permissible limits and a solar evaporation plant is being set up. The plant, when it becomes operational, will be a step towards the concept of ''Zero Release''. At Kalpakkam, the treated wastes are proposed to be diluted by circulating sea water and discharged away from the shore through a long pipe. At Narora, ion exchange followed by chemical precipitation is to be employed to treat effluents and solar evaporation process for total containment. Solid wastes are stored/dispsed in the concrete trenches, underground with the water proofing of external surfaces and the top of the trench is covered with concrete. Highly active wastes are stored/disposed in tile holes which are vaults made of steel-lined, reinforced concrete pipes. Gas cleaning, dilution and dispersion techniques are adopted to treat gaseous radioactive wastes. (M.G.B.)

  10. Radioactivity in food crops

    Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

    1983-05-01

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for /sup 137/Cs, /sup 40/K, /sup 90/Sr, /sup 226/Ra, /sup 228/Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for /sup 241/Am, /sup 7/Be, /sup 60/Co, /sup 55/Fe, /sup 3/H, /sup 131/I, /sup 54/Mn, /sup 95/Nb, /sup 210/Pb, /sup 210/Po, /sup 106/Ru, /sup 125/Sb, /sup 228/Th, /sup 232/Th, and /sup 95/Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g/sup -1/ (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins.

  11. Radioactivity in food crops

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for 137Cs, 40K, 90Sr, 226Ra, 228Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for 241Am, 7Be, 60Co, 55Fe, 3H, 131I, 54Mn, 95Nb, 210Pb, 210Po, 106Ru, 125Sb, 228Th, 232Th, and 95Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g-1 (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins

  12. The ''invisible'' radioactive scale

    Production and up-concentration of naturally occurring radioactive material (NORM) in the petroleum industry has attracted steadily increasing attention during the last 15 years. Most production engineers today associate this radioactivity with precipitates (scales) and sludges in production tubing, pumps, valves, separators, settling tanks etc., wherever water is being transported or treated. 226Ra and 228Ra are the most well known radioactive constituents in scale. Surprisingly little known is the radioactive contamination by 210Pb and progeny 210Bi and 210Po. These are found in combination with 226Ra in ordinary scale, often in layer of non-radioactive metallic lead in water transportation systems, but also in pure gas and condensate handling systems ''unsupported'' by 226Ra, but due to transportation and decay of the noble gas 222Rn in NG/LNG. This latter contamination may be rather thin, in some cases virtually invisible. When, in addition, the radiation energies are low enough for not being detectable on the equipment outer surface, its existence has for most people in the industry been a secret. The report discusses transportation and deposition mechanisms, detection methods and provides some examples of measured results from the North Sea on equipment sent for maintenance. It is concluded that a regular measurement program for this type of contamination should be mandatory under all dismantling processes of transportation and fluid handling equipment for fluids and gases offshore and onshore

  13. Radioactive material storage vessel

    In a radioactive material storage vessel having a single sealing boundary in the cylindrical portion and a double sealing boundary in the lid portion, and the outer circumference of the vessel being cooled by air, in which difference is made between the pressure in a radioactive material storage chamber and the pressure in an intermediate chamber present between a primary sealing lid and a secondary sealing lid. A valve is disposed to the primary sealing lid, which breaks the sealing between the radioactive material containing chamber and the intermediate chamber when the difference between the pressure of the containing chamber and that of the intermediate chamber is reduced to lower than a predetermined value, and a sensor for detecting pressure change in the intermediate chamber is disposed to the secondary sealing lid. In addition, a shrinkable member having at least a predetermined length and an extensible length is disposed to the primary sealing lid, and a displacement sensor capable of detecting the change of the length of the shrinkable member is disposed to the secondary sealing lid. Then, when the sealing boundary at the cylinder portion of the radioactive material containing chamber should be broken in the radioactive material storage vessel, it can be detected. (N.H.)

  14. The artificial leaf.

    Nocera, Daniel G

    2012-05-15

    To convert the energy of sunlight into chemical energy, the leaf splits water via the photosynthetic process to produce molecular oxygen and hydrogen, which is in a form of separated protons and electrons. The primary steps of natural photosynthesis involve the absorption of sunlight and its conversion into spatially separated electron-hole pairs. The holes of this wireless current are captured by the oxygen evolving complex (OEC) of photosystem II (PSII) to oxidize water to oxygen. The electrons and protons produced as a byproduct of the OEC reaction are captured by ferrodoxin of photosystem I. With the aid of ferrodoxin-NADP(+) reductase, they are used to produce hydrogen in the form of NADPH. For a synthetic material to realize the solar energy conversion function of the leaf, the light-absorbing material must capture a solar photon to generate a wireless current that is harnessed by catalysts, which drive the four electron/hole fuel-forming water-splitting reaction under benign conditions and under 1 sun (100 mW/cm(2)) illumination. This Account describes the construction of an artificial leaf comprising earth-abundant elements by interfacing a triple junction, amorphous silicon photovoltaic with hydrogen- and oxygen-evolving catalysts made from a ternary alloy (NiMoZn) and a cobalt-phosphate cluster (Co-OEC), respectively. The latter captures the structural and functional attributes of the PSII-OEC. Similar to the PSII-OEC, the Co-OEC self-assembles upon oxidation of an earth-abundant metal ion from 2+ to 3+, may operate in natural water at room temperature, and is self-healing. The Co-OEC also activates H(2)O by a proton-coupled electron transfer mechanism in which the Co-OEC is increased by four hole equivalents akin to the S-state pumping of the Kok cycle of PSII. X-ray absorption spectroscopy studies have established that the Co-OEC is a structural relative of Mn(3)CaO(4)-Mn cubane of the PSII-OEC, where Co replaces Mn and the cubane is extended in a

  15. Residual radioactivity measurements at Indus accelerator complex

    Indus-1 and Indus-2 are two Synchrotron Radiation Sources (SRS) operational at RRCAT, Indore. Indus-1 and Indus-2 are designed for maximum electron beam energy of 450 MeV and 2.5 GeV respectively. During shut down of these accelerators for maintenance purpose, residual radioactivity measurements were carried out. The residual radioactivity formation in various parts of the high energy electron accelerators is due to the beam loss taking place at these locations. The present paper describes the recent residual radioactivity measurements carried out at the electron accelerators of Indus Accelerator Complex and the radio-isotopes identified. The maximum dose rate due to induced activity obtained is 30 μSv/h, near dipole-5 of booster synchrotron after 12 h of cooling time. In case of Indus-1 and Indus-2 SRS the dose rate due to induced radioactivity is found to be of the order of 2 - 3 μSv/h. The radio isotopes identified at these beam loss locations are beta emitters that do not pose serious external hazard to the working personnel. However, precautions are to be observed while doing maintenance on activated components. The paper describes the measurements in detail with the results. (author)

  16. natural or artificial diets

    A. O. Meyer-Willerer

    2005-01-01

    Full Text Available Se probaron alimentos artificiales y naturales con larva de camarón (Litopenaeus vannamei cultivados en diferentes recipientes. Estos fueron ocho frascos cónicos con 15L, ocho acuarios con 50L y como grupo control, seis tanques de fibra de vidrio con 1500L; todos con agua marina fresca y filtrada. La densidad inicial en todos los recipientes fue de 70 nauplios/L. Aquellos en frascos y acuarios recibieron ya sea dieta natural o artificial. El grupo control fue cultivado con dieta natural en los tanques grandes que utilizan los laboratorios para la producción masiva de postlarvas. El principal producto de excreción de larva de camarón es el ión amonio, que es tóxico cuando está presente en concentraciones elevadas. Se determinó diariamente con el método colorimétrico del indofenol. Los resultados muestran diferencias en la concentración del ión amonio y en la sobrevivencia de larvas entre las diferentes dietas y también entre los diferentes recipientes. En aquellos con volúmenes pequeños comparados con los grandes, se presentó mayor concentración de amonio (500 a 750µg/L, en aquellos con dietas naturales, debido a que este ión sirve de fertilizante a las algas adicionadas, necesitando efectuar recambios diarios de agua posteriores al noveno día de cultivo para mantener este ión a una concentración subletal. Se obtuvo una baja cosecha de postlarvas (menor a 15% con el alimento artificial larvario, debido a la presencia de protozoarios, alimentándose con el producto comercial precipitado en el fondo de los frascos o acuarios. Los acuarios con larvas alimentadas con dieta natural también mostraron concentraciones subletales de amonio al noveno día; sin embargo, la sobrevivencia fue cuatro veces mayor que con dietas artificiales. Los tanques control con dietas naturales presentaron tasas de sobrevivencia (70 ± 5% similares a la reportada por otros laboratorios.

  17. Radioactive pollution: ocean environments. January 1974-May 1989 (Citations from Oceanic Abstracts). Report for January 1974-May 1989

    This bibliography contains citations concerning radioactive pollution of the marine environment. Distributions of radionuclides indicative of artificial radioactive contamination are discussed including iodine-131, various uranium isotopes, cesium-137, cobalt-60, strontium-90, ruthenium-160, and plutonium isotopes. Ecosystems considered include coral reefs and atolls, planktonic zones in the open ocean, salt marshes, estuaries, coastal waters, and the Mediterranean Sea. Sources of radioactive contamination examined include atomic bomb blasts, fossil-fuel combustion, radioactive waste disposal, and nuclear accidents. Experimental simulation of radionuclide transport in marine biota is included. (Contains 108 citations fully indexed and including a title list.)

  18. Radioactive waste processing field

    Storing space for radioactive wastes (storage tunnels) are formed underground of the sea bottom along coast. A plurality of boreholes through which sea water flows are pored vertically in a direction intersecting underground streams of brine in the ground between the tunnels and seaside. Sea water introduction pipes are joined to the upper side walls of the boreholes. The sea water introduction pipes have introduction ports protruded under the sea level of the coastal sea area region. Since sea water flows from the introduction ports to the boreholes passing through the sea water introduction pipes, sea water is always filled in the boreholes. Therefore, brine is sufficiently supplied toward the land by sea water from the boreholes, the underground stream of brine is negligibly small. This can prevent radioactive contamination due to flow of the underground water when radioactive wastes are buried in the underground near coast. (I.N.)

  19. Radioactivity - superstition and science

    Fairy-tales, myths, superstition - how was it fair, when we could still be afraid for witches and goblins. Where demons floated and nicks danced, the dry science has spreaded and disenchanted the life. If there would not be things like radioactivity, against which can be struggled in the collective well being. Then it is bad, clear, or good, it heals sicks, also clear. But what is now correct? In his usual humorous way the author, Dr. Hermann Hinsch, explains by means of numerous examples the phenomenon ''radioactivity'' and its effects on life. Provocantly but illustratively he illuminates, which position radioactive radiation has in our life and how and where we have already met it wantedly or unwantedly. Perhaps we must then something less shudder, but something more realism at such theme is surely not harmful.

  20. Disposal of Radioactive Waste

    This Safety Requirements publication applies to the disposal of radioactive waste of all types by means of emplacement in designed disposal facilities, subject to the necessary limitations and controls being placed on the disposal of the waste and on the development, operation and closure of facilities. The classification of radioactive waste is discussed. This Safety Requirements publication establishes requirements to provide assurance of the radiation safety of the disposal of radioactive waste, in the operation of a disposal facility and especially after its closure. The fundamental safety objective is to protect people and the environment from harmful effects of ionizing radiation. This is achieved by setting requirements on the site selection and evaluation and design of a disposal facility, and on its construction, operation and closure, including organizational and regulatory requirements.

  1. Natural radioactivity, age estimation

    The life in the earth depends totally on the sun. The universe was born from great explosion, the Big Bang. Practically all the materials in the nature contain radioactive nuclides. The sources that give them origin can be categorized as: 1. Cosmogenic s 2. primordial 3. anthropogenic. The application for the first and two groups of natural radionuclides it is the age estimation. Although some of the primitive ones has application in therapy of oncological patient. 1: The three groups of age estimation methods, for nuclear phenomenons are: 1. Measure of the radioactive decline of the primitive isotopes, by accumulation of stable isotopes. 2. use of the descendants of radioactive isotopes of the families of the Uranium or of the Th. 3. Measure of the cosmogenic s isotopes

  2. Reloadable radioactive generator system

    A generator system that can be reloaded with an elutable radioactive material, such as 99 molybdenum, a multiple number of times is described. The system basically comprises a column filled with alumina, a loading vial containing a predetermined amount of the elutable radioactive material, and a rinsing vial containing a sterile solution. The two vials are connected by a conduit so that when communication is achieved between the column and loading vial and an evacuated vial is placed in communication with the bottom of the column, the predetermined amount of the radioactive material in the loading vial will be transferred to the column. The procedure can be repeated as the elutable material in the column is dissipated

  3. Radioactive materials transport

    Growing public concern over the potential hazards of transporting radioactive materials has led to a considerable body of state and local restrictions, including bans in certain jurisdictions. In spite of a good safety record and the acknowledged necessity of many of these shipments, restrictive enactments continue to proliferate. Users of radioactive materials contend that these restrictions impede shipments and contribute to rising costs while, on the other hand, state and local officials are concerned with the health and safety of their citizenry. A showdown between state and local safety interests and federal promoters of unencumbered interstate commerce will occur when the proposed US Department of Transportation (DOT) highway routing rules for the shipment of radioactive materials are implemented February 1, 1982. As proposed, these rules would preempt several restrictive state and local requirements

  4. Radioactivity in the Rhine - the LWA controls North-Rhine-Westphalian surface waters

    The State Authority for Water and Waste Management has been testing the Rhine and the most important surface waters of North-Rhine Westphalia for radioactivity ever since it was founded in 1969. Radiation exposure of human beings who use Rhine water is far below the permitted maximum values of the 'radiation protection ordinance'. Pollution of the Rhine and its tributaries in North-Rhine Westphalia with artificial radioactive substances has even slightly decreased over the past ten years; pollution of the River Emscher with natural radioactive material remained high, the Lippe River now contains less radium than before. (orig./PW)

  5. Artificial frustrated spin systems

    Perrin, Y.; Chioar, I. A.; Nguyen, V. D.; Lacour, D.; Hehn, M.; Montaigne, F.; Canals, B.; Rougemaille, N.

    2015-09-01

    Complex architectures of nanostructures are routinely elaborated using bottom-up or nanofabrication processes. This technological capability allows scientists to engineer materials with properties that do not exist in nature, but also to manufacture model systems to explore fundamental issues in condensed matter physics. Two-dimensional frustrated arrays of magnetic nanostructures are one class of systems for which theoretical predictions can be tested experimentally. These systems have been the subject of intense research in the last few years and allowed the investigation of a rich physics and fascinating phenomena, such as the exploration of the extensively degenerate ground-state manifolds of spin ice systems, the evidence of new magnetic phases in purely two-dimensional lattices, and the observation of pseudoexcitations involving classical analogues of magnetic monopoles. We show here, experimentally and theoretically, that simple magnetic geometries can lead to unconventional, non-collinear spin textures. For example, kagome arrays of inplane magnetized nano-islands do not show magnetic order. Instead, these systems are characterized by spin textures with intriguing properties, such as chirality, coexistence of magnetic order and disorder, and charge crystallization. Magnetic frustration effects in lithographically patterned kagome arrays of nanomagnets with out-of-plane magnetization also lead to an unusal, and still unknown, magnetic ground state manifold. Besides the influence of the lattice geometry, the micromagnetic nature of the elements constituting the arrays introduce the concept of chiral magnetic monopoles, bringing additional complexity into the physics of artificial frustrated spin systems.

  6. Artificial Immune Systems Tutorial

    Aickelin, Uwe

    2008-01-01

    The biological immune system is a robust, complex, adaptive system that defends the body from foreign pathogens. It is able to categorize all cells (or molecules) within the body as self-cells or non-self cells. It does this with the help of a distributed task force that has the intelligence to take action from a local and also a global perspective using its network of chemical messengers for communication. There are two major branches of the immune system. The innate immune system is an unchanging mechanism that detects and destroys certain invading organisms, whilst the adaptive immune system responds to previously unknown foreign cells and builds a response to them that can remain in the body over a long period of time. This remarkable information processing biological system has caught the attention of computer science in recent years. A novel computational intelligence technique, inspired by immunology, has emerged, called Artificial Immune Systems. Several concepts from the immune have been extracted an...

  7. Artificial Immune Systems

    Aickelin, Uwe

    2009-01-01

    The biological immune system is a robust, complex, adaptive system that defends the body from foreign pathogens. It is able to categorize all cells (or molecules) within the body as self-cells or non-self cells. It does this with the help of a distributed task force that has the intelligence to take action from a local and also a global perspective using its network of chemical messengers for communication. There are two major branches of the immune system. The innate immune system is an unchanging mechanism that detects and destroys certain invading organisms, whilst the adaptive immune system responds to previously unknown foreign cells and builds a response to them that can remain in the body over a long period of time. This remarkable information processing biological system has caught the attention of computer science in recent years. A novel computational intelligence technique, inspired by immunology, has emerged, called Artificial Immune Systems. Several concepts from the immune have been extracted an...

  8. Your radioactive garden

    The booklet on radiation risks from nuclear waste is based on lectures given by the author at Westminster School (United Kingdom) and elsewhere during 1986. A description is given of naturally-occurring radioactivity, and the health risks due to this radiation. The types of radioactive wastes produced by the nuclear industry are described, including low-level wastes, short-lived and long-lived intermediate-level wastes, and high level wastes. These wastes are discussed with respect to their potential health risks and their disposal underground. (U.K.)

  9. The radioactive wastes management

    The different types of radioactive waste are presented in this paper in the frame of the official categories which take into account their dangerousness and the lifetimes of their radioactivity. It is indicated how the less dangerous of them are handled in France. The ways of protecting the environment from the more dangerous ones (high activity and long lifetimes) are object of studies. Scientific questions, in the field of chemistry and physical chemistry, related to the implementation of deep underground repository facilities with full respect of nuclear safety are presented. (authors)

  10. Radioactive waste management

    First, some general informations are given about radioactive waste, e.g. arising of waste, classification, intermediate deposition and transport, as well as about the multi-barrier concept. Then, emphasis is laid on the internationally favoured vitrification of high-active waste. Safety requirements and the physical-chemical characteristics of the waste forms are described as are the different technical vitrification processes. Moreover, alternative solidification products such as ceramic materials and synthetic rocks were discussed. In addition, the worldwide technical concepts for the management and final disposal of radioactive waste are summarized. (orig./HP)

  11. Radioactive waste management

    The purpose of this document is to set out the Government's current strategy for the long term in the management of radioactive wastes. It takes account of the latest developments, and will be subject to review in the light of future developments and studies. The subject is discussed under the headings: what are radioactive wastes; who is responsible; what monitoring takes place; disposal as the objective; low-level wastes; intermediate-level wastes; discharges from Sellafield; heat generating wastes; how will waste management systems and procedures be assessed; how much more waste is there going to be in future; conclusion. (U.K.)

  12. Radioactive wastes in Oklo

    The acceptance of the Nuclear Energy as electric power supply implies to give answer to the population on the two main challenges to conquer in the public opinion: the nuclear accidents and the radioactive wastes. Several of the questions that are made on the radioactive wastes, its are the mobility migration of them, the geologic stability of the place where its are deposited and the possible migration toward the aquifer mantels. Since the half lives of the radioactive waste of a Nuclear Reactor are of several hundred of thousands of years, the technical explanations to the previous questions little convince to the public in general. In this work summary the results of the radioactive waste generated in a natural reactor, denominated Oklo effect that took place in Gabon, Africa, it makes several thousands of millions of years, a lot before the man appeared in the Earth. The identification of at least 17 reactors in Oklo it was carried out thanks to the difference in the concentrations of Uranium 235 and 238 prospective, and to the analysis of the non-mobility of the radioactive waste in the site. It was able by this way to determine that the reactors with sizes of hardly some decimeter and powers of around 100 kilowatts were operating in intermittent and spontaneous form for space of 150,000 years, with operation cycles of around 30 minutes. Recent studies have contributed information valuable on the natural confinement of the radioactive waste of the Oklo reactors in matrixes of minerals of aluminum phosphate that caught and immobilized them for thousands of millions of years. This extracted information from the nature contributes guides and it allows 'to verify' the validity of the current proposals on the immobilization of radioactive wastes of a nuclear reactor. This work presents in clear and accessible form to the public in general on the secure 'design', operation, 'decommissioning' and 'storage' of the radioactive waste of the reactors that the nature put

  13. Radioactive waste processing method

    When granular materials comprising radioactive wastes containing phosphorus are processed at first in a fluidized bed type furnace, if the granular materials are phosphorus-containing activated carbon, granular materials comprising alkali compound such as calcium hydroxide and barium hydroxide are used as fluidizing media. Even granular materials of slow burning speed can be burnt stably in a fluidizing state by high temperature heat of the fluidizing media, thereby enabling to take a long burning processing time. Accordingly, radioactive activated carbon wastes can be processed by burning treatment. (T.M.)

  14. Radioactivity yesterday and today

    As an exhibition on the history of radioactivity from Homer to Oppenheimer has been organised in the Palais de la Decouverte in Paris, this article first recalls some atom characteristics and interactions between electrostatic forces within the atom. The author recalls how radioactivity has been unexpectedly discovered at the end of the 19. century, recalls the first works of characterization performed by Marie Curie and those performed by other scientists who perceived the opportunities for various applications. More recent works are also addressed like other forms of nucleus disintegrations, the generation of heavy ion beams, and double beta decay

  15. Method of packaging radioactive wastes

    Purpose: To decrease the leaching of radioactive waste in marine environment. Method: Fillers are placed between a drum can and an inner cage for charging radioactive wastes in order to prevent the leakage of the radioactive wastes from the drum can. Leaching inhibitors for radioactive materials are mixed with the fillers made of organic substance such as asphalts and plastics. The leaching inhibitors are made of materials in the similar chemical form to that of the radioactive materials in the wastes and mixed into the fillers to the saturation limit of dissolution. For the radioactive wastes containing spent adsorbents for iodine, the inhibitors are made of silver nitrates. (Ikeda, J.)

  16. Tissue culture of osteogenic sarcoma in rats, induced by radioactive phosphorus P-32 and the effect of the anti-cancerous agents on these tumor cells under tissue culture

    Small pieces of osteogenic sarcoma, induced into albino rats of the C.F. Wistar strain by injection of radioactive phosphorus 32P, were cultured in mixtures of Eagle's minimum essential medium and 20% calf serum. The tumor cells cultured in this way were transplanted into the subcutaneous tissue or the intraabdominal cavity to healthy albino rats. The effect of the anticancerous agents was evaluated by the decrease of nucleic acid composition in these cultured tumor cells. As anti-cancerous agents, cyclophosphamide (CPA), mitomycin C(MMC), and 5-fluorouracil(5-FU) were put into contact with the tumor cells in cultures for two hours under the following dilutions: CPA; 10-6, 10-5, 10-4 g/ml. MMC; 2 x 10-8, 2 x 10-7, 2 x 10-6 g/ml. 5-FU; 2 x 10-6, 2 x 10-5, 2 x 10-4 g/ml. The results are as follows: Three of the seven osteogenic sarcomas in rats were successfully cultured, one of them through more than eighteen generations. After about five hundred thousand cultured cells had been transplanted into the subcutaneous tissues or abdominal cavities of rats, tumors grew in all of them. The histological findings of the tumors in the second generation were quite similar to those of the original tumor. The same process was repeated three times and the tumor showed histogical findings similar to those of the original ones. The capability of nucleic acid synthesis in these cells was decreased at twenty fours after CPA contact and at forty eight hours after MMC. (J.P.N.)

  17. Handling of radioactive sources in Ecuador

    This document describes the following aspects: sealed and unsealed radioactive sources, radiation detectors, personnel and area monitoring, surface pollution, radioactive wastes control and radioactive sources transferring. (The author)

  18. Artificial Life Meets Computational Creativity?

    McMullin, Barry

    2009-01-01

    I (briefly) review the history of work in Artificial Life on the problem of the open-ended evolutionary growth of complexity in computational worlds. This is then put into the context of evolutionary epistemology and human creativity.

  19. Darwin, artificial selection, and poverty.

    Sanchez, Luis

    2010-03-01

    This paper argues that the processes of evolutionary selection are becoming increasingly artificial, a trend that goes against the belief in a purely natural selection process claimed by Darwin's natural selection theory. Artificial selection is mentioned by Darwin, but it was ignored by Social Darwinists, and it is all but absent in neo-Darwinian thinking. This omission results in an underestimation of probable impacts of artificial selection upon assumed evolutionary processes, and has implications for the ideological uses of Darwin's language, particularly in relation to poverty and other social inequalities. The influence of artificial selection on genotypic and phenotypic adaptations arguably represents a substantial shift in the presumed path of evolution, a shift laden with both biological and political implications. PMID:20812798

  20. Artificial Reefs and Ocean Dumping.

    Glueck, Richard D.

    1983-01-01

    Activities and instructional strategies for two multigrade lessons are provided. Activity objectives include describing an artificial reef (such as a sunken ocean liner) as an ecosystem, knowing animal types in the ecosystem, and describing a food web. (JN)