WorldWideScience

Sample records for alpha radiation influencia

  1. Influence of some exo nucleases in response to the induced genetic damage in Escherichia coli by alpha radiation; Influencia de algunas exonucleasas en respuesta al dano genetico inducido en Escherichia coli por radiacion alfa

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar M, M

    2005-07-01

    Within the strategies with those that E. coli counts to overcome to the genetic damage there is the SOS response, a group of genes that participate in repair and/or tolerance that it confers to the bacteria major opportunities of surviving. These genes are repressed and its only are expressed when it happens genetic damage. So that this system is activated it is necessary that DNA of a band exists and in this sense the double ruptures (RDB) its are not able to induce this response unless there is a previous processing. In stumps with defects in certain genes that have to do with repair of RDB (as recO, recJ and xonA) the activity of SOS is smaller than in a wild stump what suggests that these participate in the previous processes to the activation of the response. The ionizing radiation produce among other many lesions, RDB in greater or smaller proportion, depending on the ionization capacity. A parameter to evaluate this capacity is the lineal energy transfer (LET), defined as the average energy given by unit of distance travelled. In general the LET of the corpuscular radiations is a lot but high that of the electromagnetic one, for what produces bigger quantity of ionizations inside a restricted zone and it increases by this way the probability that RDB has been generated. This work has for object to infer the participation of xonA and recJ in this response and to evaluate the damage produced by ionizing radiation of different LET (alpha particles of different energies) in a stump with all the functional repair mechanisms. Its were considered two parameters: the survival and the activity of SOS evaluated by means of the chromo test. The results indicate that the activity of these exo nucleases is necessary for the repair of RDB as well as for the processing of lesions foresaw to the activation of SOS. As for the treatment with alphas of different energies is observed that so much the survival like the activity of SOS vary as the LET of the radiation changes

  2. Measurement of $\\alpha_{s}$ with Radiative Hadronic Events

    CERN Document Server

    Abbiendi, G; Åkesson, P F; Alexander, G; Anagnostou, G; Anderson, K J; Asai, S; Axen, D; Bailey, I; Barberio, E; Barillari, T; Barlow, R J; Batley, R J; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, S; Biebel, O; Boeriu, O; Bock, P; Boutemeur, M; Braibant, S; Brown, R M; Burckhart, H J; Campana, S; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Ciocca, C; Csilling, A; Cuffiani, M; Dado, S; Dallavalle, M; de Roeck, A; De Wolf, E A; Desch, K; Dienes, B; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, F; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Gagnon, P; Gary, J W; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Gross, E; Grunhaus, J; Gruwé, M; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harel, A; Hauschild, M; Hawkes, C M; Hawkings, R; Herten, G; Heuer, R D; Hill, J C; Horváth, D; Igo-Kemenes, P; Ishii, K; Jeremie, H; Jovanovic, P; Junk, T R; Kanzaki, J; Karlen, D; Kawagoe, K; Kawamoto, T; Keeler, R K; Kellogg, R G; Kennedy, B W; Kluth, S; Kobayashi, T; Kobel, M; Komamiya, S; Kramer, T; Krasznahorkays, A Jr; Krieger, P; Von Krogh, J; Kühl, T; Kupper, M; Lafferty, G D; Landsman, H; Lanske, D; Lellouch, D; Letts, J; Levinson, L; Lillich, J; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, A; Ludwig, J; Mader, W; Marcellini, S; Martin, A J; Mashimo, T; Mättig, P; McKenna, J; McPherson, R A; Meijers, F; Menges, W; Merritt, F S; Mes, H; Meyer, N; Michelini, A; Mihara, S; Mikenberg, G; Miller, D J; Mohr, W; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; O'Neale, S W; Oh, A; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Pilcher, J E; Pinfold, J L; Plane, D E; Pooth, O; Przybycien, M; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Roney, J M; Rossi, A M; Rozen, Y; Runge, K; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schiecks, J; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Seuster, R; Shears, T G; Shen, B C; Sherwood, P; Skuja, A; Smith, A M; Sobie, R J; Söldner-Rembold, S; Spanó, F; Stahl, A; Strom, D; Ströhmer, R; Tarem, S; Tasevsky, M; Teuscher, R; Thomson, M A; Torrence, E; Toya, D; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vollmer, C F; Vannerem, P; Vertesi, R; Verzocchi, M; Voss, H; Vossebeld, J; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Zer-Zion, D; Zivkovic, L

    2008-01-01

    Hadronic final states with a hard isolated photon are studied using data taken at centre-of-mass energies around the mass of the Z0 boson with the OPAL detector at LEP. The strong coupling alpha S is extracted by comparing data and QCD predictions for event shape observables at average reduced centre-of-mass energies ranging from 24 GeV to 78 GeV, and the energy dependence of alpha S is studied. Our results are consistent with the running of alpha S as predicted by QCD and show that within the uncertainties of our analysis event shapes in hadronic Z0 decays with hard and isolated photon radiation can be described by QCD at reduced centre-of-mass energies. Combining all values from different event shape observables and energies gives alpha S (Mz)=0.1182 pm 0.0015(stat.) pm 0.0101(syst.).

  3. Biomarkers of Alpha Particle Radiation Exposure

    Science.gov (United States)

    2014-04-01

    work towards the identification of gene-based biomarkers of alpha-particle radiation exposure. Peripheral blood mononuclear cells (PBMN) isolated from...manipulation et l’exposition au rayonnement ionisant chez les humains . CSSP-2012-CD-1117 and CSSP-2012-CD-1114 iii Table of contents...19 Acknowledgements This work was supported by the Centre for

  4. Alpha Radiation Effects on Silicon Oxynitride Waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Morichetti, Francesco; Grillanda, Stefano; Manandhar, Sandeep; Shutthanandan, Vaithiyalingam; Kimerling, Lionel; Melloni, Andrea; Agarwal, Anuradha M.

    2016-09-21

    Photonic technologies are today of great interest for use in harsh environments, such as outer space, where they can potentially replace current communication systems based on radiofrequency components. However, very much alike to electronic devices, the behavior of optical materials and circuits can be strongly altered by high-energy and high-dose ionizing radiations. Here, we investigate the effects of alpha () radiation with MeV-range energy on silicon oxynitride (SiON) optical waveguides. Irradiation with a dose of 5×1015 cm-2 increases the refractive index of the SiON core by nearly 10-2, twice as much that of the surrounding silica cladding, leading to a significant increase of the refractive index contrast of the waveguide. The higher mode confinement induced by -radiation reduces the loss of tightly bent waveguides. We show that this increases the quality factor of microring resonators by 20%, with values larger than 105 after irradiation.

  5. Apparatus for detecting alpha radiation in difficult access areas

    International Nuclear Information System (INIS)

    Steadman, P.; MacArthur, D.W.

    1997-01-01

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

  6. Measurement of {alpha}{sub s} with radiative hadronic events

    Energy Technology Data Exchange (ETDEWEB)

    Abbiendi, G.; Braibant, S.; Capiluppi, P.; Ciocca, C.; Cuffiani, M.; Dallavalle, M.; Fabbri, F.; Giacomelli, G.; Giacomelli, P.; Marcellini, S.; Michelini, A.; Rossi, A.M. [Dipartimento di Fisica dell' Universita di Bologna and INFN, Bologna (Italy); Ainsley, C.; Batley, R.J.; Carter, J.R.; Hill, J.C.; Thomson, M.A.; Ward, C.P.; Ward, D.R. [Cavendish Laboratory, Cambridge (United Kingdom); Aakesson, P.F.; Burckhart, H.J.; De Roeck, A.; Ferrari, P.; Frey, A.; Gruwe, M.; Hauschild, M.; Hawkings, R.; Meijers, F.; Oh, A.; Plane, D.E.; Rembser, C.; Scharff-Hansen, P.; Schroeder, M.; Smith, A.M.; Wells, P.S.; Wengler, T. [CERN, European Organisation for Nuclear Research, Geneva 23 (Switzerland); Alexander, G.; Bella, G.; Etzion, E.; Grunhaus, J.; Tsur, E. [Tel Aviv Univ., Department of Physics and Astronomy, Tel Aviv (Israel); Anagnostou, G.; Bell, P.J.; Charlton, D.G.; Hawkes, C.M.; Jovanovic, P.; O' Neale, S.W.; Turner-Watson, M.F.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wilson, J.A. [Univ. of Birmingham, School of Physics and Astronomy, Birmingham (United Kingdom); Anderson, K.J.; Gupta, A.; Merritt, F.S.; Oreglia, M.J.; Pilcher, J.E.; Teuscher, R. [Univ. of Chicago, Enrico Fermi Institute and Department of Physics, Chicago, IL (United States); Asai, S.; Ishii, K.; Kawagoe, K.; Kawamoto, T.; Kobayashi, T.; Komamiya, S.; Mashimo, T.; Mihara, S.; Mori, T.; Nanjo, H.; Orito, S.; Saeki, T.; Toya, D.; Ueda, I.; Yamashita, S. [Univ. of Tokyo, International Centre for Elementary Particle Physics and Department of Physics, Tokyo (Japan)]|[Kobe Univ., Kobe (Japan); Axen, D.; McKenna, J. [Univ. of British Columbia, Department of Physics, Vancouver, BC (Canada); Bailey, I.; Karlen, D.; Keeler, R.K.; McPherson, R.A.; Roney, J.M.; Sobie, R. [Univ. of Victoria, Department of Physics, P.O. Box 3055, Victoria, BC (Canada); Barberio, E. [CERN, European Organisation for Nuclear Research, Geneva 23 (Switzerland)]|[Univ. of Melbourne, Victoria (Australia)] [and others

    2008-01-15

    Hadronic final states with a hard isolated photon are studied using data taken at centre-of-mass energies around the mass of the Z boson with the OPAL detector at LEP. The strong coupling {alpha}{sub s} is extracted by comparing data and QCD predictions for event shape observables at average reduced centre-of-mass energies ranging from 24 GeV to 78 GeV, and the energy dependence of {alpha}{sub s} is studied. Our results are consistent with the running of {alpha}{sub s} as predicted by QCD and show that within the uncertainties of our analysis event shapes in hadronic Z decays with hard and isolated photon radiation can be described by QCD at reduced centre-of-mass energies. Combining all values from different event shape observables and energies gives {alpha}{sub s}(M{sub Z})=0.1182{+-}0.0015(stat.){+-}0.0101(syst.). (orig.)

  7. RAMs: the problem of transient errors due to alpha radiation

    International Nuclear Information System (INIS)

    Goujon, Pierre.

    1980-01-01

    Errors that remained unexplained for a long time have occurred with dynamic random access memories. It has been known since 1978 that they are due to stray alpha radiation. A good understanding of this phenomenon enables its effects to be neutralized and the reliability of the products to be guarantied [fr

  8. Alpha radiation gauge for the measurement of gas density

    International Nuclear Information System (INIS)

    Lech, M.

    1977-01-01

    Alpha gauge for the measurement of gas density with thick alfa source, has been developed. The gauge is based on radiation transmission through a space filled with gas and total-count principle. Air density can be measured in the range 1,2 - 1,27 kg m -3 with a maximum standard deviation of 2 x 10 -3 kg m -3 . (author)

  9. [Effects of thymosin alpha-1 on radiation-induced pneumonitis].

    Science.gov (United States)

    Yu, Rong; Sun, Yu; Cai, Qing; Li, Yongheng; Zhu, Guangying

    2011-03-01

    Radiation-induced lung injure is one of the major factors of limitation in radiotherapy for lung cancer. Whether the use of thymosin and radiotherapy simultaneously would increase the radiation-induced lung injure is unclear. The aim of this study is to evaluate the effects of thymosin alpha-1 on radiation induced pneumonitis in mice. Three groups of mice, control (C), radiation alone (RT), thymosin alpha-1 plus radiation (T+RT), were entered into the study. The weight and mortality of mice, pleural effusion, quantity of protein and cell count in the bronchoalvealar lavage (BAL) and pulmonary fibrosis score were evaluated as the outcome measures. The mortality ratio of the T+RT and RT groups were 3/14, 2/10, respectively. The time of death were all in the 23-24 weeks after radiotherapy. There was no pleural effusion in the T+RT group other than 2/2 occurred in RT group. The quantity of protein, cell number and neutrophil number in the BAL and lung coefficient in mice of T+RT group were remarkably lower than that of RT group, but the BALF macrophages number was remarkably higher than that in RT group in the 8 weeks. The quantity of protein, cell number, neutrophil number and macrophages number in the BAL, lung coefficient, the scores of lung fibrosis in mice of T+RT group were significantly lower than that of RT group in the 24 weeks. All test data were lowest in mice of C group. And there was no obvious pulmonary fibrosis in the mice of C group. Thymosin alpha-1 could relieve radiation-induced acute and late pulmonary injuries.

  10. Effects of Thymosin Alpha-1 on Radiation-induced Pneumonitis

    Directory of Open Access Journals (Sweden)

    Rong YU

    2011-03-01

    Full Text Available Background and objective Radiation-induced lung injure is one of the major factors of limitation in radiotherapy for lung cancer. Whether the use of thymosin and radiotherapy simultaneously would increase the radiationinduced lung injure is unclear. The aim of this study is to evaluate the effects of thymosin alpha-1 on radiation induced pneumonitis in mice. Methods Three groups of mice, control (C, radiation alone (RT, thymosin alpha-1 plus radiation (T+RT, were entered into the study. The weight and mortality of mice, pleural effusion, quantity of protein and cell count in the bronchoalvealar lavage (BAL and pulmonary fibrosis score were evaluated as the outcome measures. Results The mortality ratio of the T+RT and RT groups were 3/14, 2/10, respectively. The time of death were all in the 23-24 weeks after radiotherapy. There was no pleural effusion in the T+RT group other than 2/2 occured in RT group. The quantity of protein, cell number and neutrophil number in the BAL and lung coefficient in mice of T+RT group were remarkably lower than that of RT group, but the BALF macrophages number was remarkably higher than that in RT group in the 8 weeks. The quantity of protein, cell number, neutrophil number and macrophages number in the BAL, lung coefficient, the scores of lung fibrosis in mice of T+RT group were significantly lower than that of RT group in the 24 weeks. All test data were lowest in mice of C group. And there was no obvious pulmonary fibrosis in the mice of C group. Conclusion Thymosin alpha-1 could relieve radiation-induced acute and late pulmonary injuries.

  11. Radiation induced structural changes in alpha-copper-zinc alloys

    International Nuclear Information System (INIS)

    Schuele, W.; Gieb, M.

    1991-01-01

    During irradiation of alpha-copper-zinc alloys with high energy electrons and protons a decrease of the electrical resistivity due to an increase of the degree of short range order is observed through radiation enhanced diffusion followed by an increase of the electrical resistivity through the formation of radiation induced interstitial clusters. The initial formation rate of interstitial clusters increases about linearly with the displacement rate for electron and proton irradiation. The largest initial formation rate is found between 60 and 130 0 C becoming negligibly small above 158 0 C and decreases drastically below 60 0 C. The dynamic steady state interstitial cluster concentration increases with decreasing irradiation temperature in the investigated temperature range between 158 and 40 0 C. Above 158 0 C the formation rate of interstitial clusters is negligibly small. Thus the transition temperature for radiation induced interstitial cluster formation is 158 0 C, depending mainly on the migration activation energy of vacancies. The radiation induced interstitial clusters are precipitates in those alloys in which the diffusion rate of the undersized component atoms via an interstitialcy diffusion mechanism is larger than that of the other atoms

  12. Risk estimates for the health effects of alpha radiation

    International Nuclear Information System (INIS)

    Thomas, D.C.; McNeill, K.G.

    1981-09-01

    This report provides risk estimates for various health effects of alpha radiation. Human and animal data have been used to characterize the shapes of dose-response relations and the effects of various modifying factors, but quantitative risk estimates are based solely on human data: for lung cancer, on miners in the Colorado plateau, Czechoslovakia, Sweden, Ontario and Newfoundland; for bone and head cancers, on radium dial painters and radium-injected patients. Slopes of dose-response relations for lung cancer show a tendency to decrease with increasing dose. Linear extrapolation is unlikely to underestimate the excess risk at low doses by more than a factor of l.5. Under the linear cell-killing model, our best estimate

  13. Dislocations and radiation damage in {alpha}-uranium; Dislocations et effets des radiations dans l'uranium {alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Leteurtre, J. [Commissariat a l' Energie Atomique, 92 - Fontenay-Aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    Dislocations in {alpha}-uranium were studied by electron microscopy. Electropolishing of thin foils was performed at low temperature (-110 deg. C) to prevent oxidation. Burgers vectors of twins dislocations are defined. Interactions between slip and twinning are studied from both experimental and theoretical point of view. Samples irradiated at several burn-up were examined. In order to explain our micrographic results, and also all information gathered in literature about radiation damage in {alpha}-uranium, a coherent model is propound for the fission particles effects. We analyse the influences of parameters: temperature, dislocation density, impurity content. The number of point defects created by one initial fission is determined for pure and annealed metal. The importance of the self-anneal which occurs immediately in each displacement spike, and the anneal due to a new fission on the damage resulting from a previous fission, are estimated. The focussing distance in [100] direction is found to be about 1000 Angstrom, at 4 deg. K. (author) [French] Ce travail est une etude par microscopie electronique des dislocations induites dans l'uranium {alpha}, soit par deformation plastique, soit par irradiation. Une methode de preparation des lames minces a basse temperature (-110 deg. C) a ete mise au point. Les vecteurs de Burgers des diverses dislocations de macles de ce metal ont ete definis. Les interactions glissements- maclages sont etudiees experimentalement et theoriquement. Des echantillons irradies a divers taux de combustion ont ete examines. Pour expliquer nos resultats micrographiques, et aussi l'ensemble des informations recueillies dans la litterature concernant l'endommagement par irradiation de l'uranium-{alpha}, nous proposons un modele coherent de l'effet des fragments de fission dans ce metal. L'influence des parametres: temperature, densite de dislocations, impuretes est analysee. Le nombre de defauts ponctuels crees

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

    Science.gov (United States)

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

    2018-02-01

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

  15. Influence of ionizing radiation on Trypanosoma cruzi; Influencia da radiacao ionizante sobre o Trypanosoma cruzi

    Energy Technology Data Exchange (ETDEWEB)

    Szarota, Rosa Maria

    2006-07-01

    Chagas's disease is one of the major public health problems in South America, promoting high prejudice to the local population. Despite the massive efforts to control it, this disease has no cure and presents puzzling unsolved questions. Considering that many researchers have used ionizing radiation to modify protozoans or biomolecules, we investigated the immunological response aspects of susceptible and resistant mice using irradiated parasites. Low radiation doses preserved the reproductive and invasive capacities of the parasite. Both susceptible and resistant animals, after immunization with irradiated parasites produced specific antibodies. After a challenge, the animals presented low parasitaemia, excepting those immunized with the antigen irradiated with higher doses. Using low radiation doses, we were able to selectively isolate trypomastigotes, leading to an improvement in the quality of the immune response, as previously reported when performing complement system assays. These data highlight the importance of selecting trypomastigote forms for immunization against T. cruz; and point towards ionizing radiation as an alternative to achieve this selection, since when this procedure is performed using complement, the subsequent steps are impaired by the difficulties to remove this component from the system. (author)

  16. Proposal of a weight factor for alpha radiation aiming biota radioprotection

    International Nuclear Information System (INIS)

    Pereira, Wagner de S.; Py Junior, Delcy de A.; Kelecom, Alphonse; Goncalves, Simone

    2009-01-01

    Several proposals based on the environmental radioprotection of calculating the absorbed dose in biota have been suggested. The absorbed dose expresses the deposition of energy per mass unit. The differences in biological effects of the absorbed dose can be quantified by applying a correction factor to the absorbed dose. The correction factor for radiation is easier to establish, because radiations exist in smaller number (alpha, beta, neutrons and photons) and can be set for groups of organisms. This work aims to propose a correction factor for radiation, in order to adequate the concept of absorbed dose currently used to the concept of equivalent dose. A survey of the literature on correction factors proposed for alpha radiation was carried out and, when possible, the biological endpoint was identified, as well as the radionuclide and the biological target. A variation of the weight factor for alpha radiation from 1 to 377 was observed and a number of biological endpoints, biological target and alpha emitter radionuclide were identified. Finally we propose a weight value for alpha radiation of 40, and we propose also the name of correction factor for radiation alpha as being ecological radiation weighting factor (WRE) the name 'equivalent dose for flora and fauna' (HTFF) to name of the new dose. (author)

  17. Tumor necrosis factor alpha selectively sensitizes human immunodeficiency virus-infected cells to heat and radiation

    International Nuclear Information System (INIS)

    Wong, G.H.; McHugh, T.; Weber, R.; Goeddel, D.V.

    1991-01-01

    We report here that infection of the human T-cell line HUT-78 with human immunodeficiency virus (HIV) increases its sensitivity to heat and radiation toxicity. A possible explanation for this result may be the reduced expression of manganous superoxide dismutase (MnSOD) in HIV-infected cells compared to uninfected cells. Tumor necrosis factor alpha (TNF-alpha) further sensitizes HIV-infected cells but not uninfected cells to heat and radiation. This is consistent with the ability of TNF-alpha to induce the expression of MnSOD in uninfected but not in HIV-infected cells. HIV-infected HUT-78 cell lines engineered to overexpress MnSOD are more resistant to heat and radiation than HIV-infected cells that do not overexpress MnSOD. However, treatment with TNF-alpha still sensitizes these cells to heat and radiation

  18. Nanodosimetry and nanodosimetric-based models of radiation action for radon alpha particles

    International Nuclear Information System (INIS)

    1992-01-01

    The objective of our research work is to provide -- with the aid of biophysical models of radiation action -- information on human risks following exposure to radon alpha particles. The approach proposed consists of (1) developing appropriate models (parametric and non-parametric) for alpha radiation induction of relevant end points (survival, cellular transformation), (2) providing an accurate physical characterization of the particle tracks in terms of nanodosimetric distributions, (3) supporting the models by detailed, molecular studies of the direct and indirect effects of alpha particles on DNA. Activities in the second year of this project are described

  19. Ly{alpha} DOMINANCE OF THE CLASSICAL T TAURI FAR-ULTRAVIOLET RADIATION FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Schindhelm, Eric [Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80303 (United States); France, Kevin; Brown, Alexander [Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Herczeg, Gregory J. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Bergin, Edwin [Department of Astronomy, University of Michigan, 830 Dennison Building, 500 Church Street, Ann Arbor, MI 48109 (United States); Yang Hao [Institute of Astrophysics, Central China Normal University, Wuhan, Hubei 430079 (China); Brown, Joanna M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-78, Cambridge, MA 02138 (United States); Linsky, Jeffrey L. [JILA, University of Colorado and NIST, 440 UCB, Boulder, CO 80309 (United States); Valenti, Jeff, E-mail: eric@boulder.swri.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2012-09-01

    Far-ultraviolet (FUV) radiation plays an important role in determining chemical abundances in protoplanetary disks. H I Lyman {alpha} (Ly{alpha}) is suspected to be the dominant component of the FUV emission from Classical T Tauri Stars (CTTSs), but is difficult to measure directly due to circumstellar and interstellar H I absorption. To better characterize the intrinsic Ly{alpha} radiation, we present FUV spectra of 14 CTTSs taken with the Hubble Space Telescope Cosmic Origins Spectrograph and Space Telescope Imaging Spectrograph instruments. H{sub 2} fluorescence, commonly seen in the spectra of CTTSs, is excited by Ly{alpha} photons, providing an indirect measure of the Ly{alpha} flux incident upon the warm disk surface. We use observed H{sub 2} progression fluxes to reconstruct the CTTS Ly{alpha} profiles. The Ly{alpha} flux correlates with total measured FUV flux, in agreement with an accretion-related source of FUV emission. With a geometry-independent analysis, we confirm that in accreting T Tauri systems Ly{alpha} radiation dominates the FUV flux ({approx}1150 A -1700 A). In the systems surveyed this one line comprises 70%-90% of the total FUV flux.

  20. The semiconductor doping with radiation defects via proton and alpha-particle irradiation. Review

    CERN Document Server

    Kozlov, V A

    2001-01-01

    Paper presents an analytical review devoted to semiconductor doping with radiation defects resulted from irradiation by light ions, in particular, by protons and alpha-particles. One studies formation of radiation defects in silicon, gallium arsenide and indium phosphide under light ion irradiation. One analyzes effect of proton and alpha-particle irradiation on electric conductivity of the above-listed semiconducting materials. Semiconductor doping with radiation defects under light ion irradiation enables to control their electrophysical properties and to design high-speed opto-, micro- and nanoelectronic devices on their basis

  1. Development of optical monitor of alpha radiations based on CR-39.

    Science.gov (United States)

    Joshirao, Pranav M; Shin, Jae Won; Vyas, Chirag K; Kulkarni, Atul D; Kim, Hojoong; Kim, Taesung; Hong, Seung-Woo; Manchanda, Vijay K

    2013-11-01

    Fukushima accident has highlighted the need to intensify efforts to develop sensitive detectors to monitor the release of alpha emitting radionuclides in the environment caused by the meltdown of the discharged spent fuel. Conventionally, proportional counting, scintillation counting and alpha spectrometry are employed to assay the alpha emitting radionuclides but these techniques are difficult to be configured for online operations. Solid State Nuclear Track Detectors (SSNTDs) offer an alternative off line sensitive technique to measure alpha emitters as well as fissile radionuclides at ultra-trace level in the environment. Recently, our group has reported the first ever attempt to use reflectance based fiber optic sensor (FOS) to quantify the alpha radiations emitted from (232)Th. In the present work, an effort has been made to develop an online FOS to monitor alpha radiations emitted from (241)Am source employing CR-39 as detector. Here, we report the optical response of CR-39 (on exposure to alpha radiations) employing techniques such as Atomic Force Microscopy (AFM) and Reflectance Spectroscopy. In the present work GEANT4 simulation of transport of alpha particles in the detector has also been carried out. Simulation includes validation test wherein the projected ranges of alpha particles in the air, polystyrene and CR-39 were calculated and were found to agree with the literature values. An attempt has been further made to compute the fluence as a function of the incidence angle and incidence energy of alphas. There was an excellent correlation in experimentally observed track density with the simulated fluence. The present work offers a novel approach to design an online CR-39 based fiber optic sensor (CRFOS) to measure the release of nanogram quantity of (241)Am in the environment. © 2013 Elsevier Ltd. All rights reserved.

  2. Low dose radiation and ALARA: the potential risks to patients and staff from alpha-therapy

    Energy Technology Data Exchange (ETDEWEB)

    Priest, N.D. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

    2014-07-01

    This year a new drug containing radium-223, an alpha-emitting radionuclide, was approved for use by the US Food and Drug Administration for the palliative treatment of advanced prostate cancer metastases. Other drugs containing short-lived alpha-emitters are on clinical trial in Europe. Commonly, these employ a radionuclide attached to an antibody that specifically targets tumor cells to produce a highly localized radio-therapeutic dose to the tumor. However, normal tissues within the body will also be irradiated, albeit sometimes at low dose, and the question arises as to whether this presents a significant additional risk to the patient. Similarly, medical staff that handle these radionuclides could receive intakes of the radionuclides. What is the risk to staff? To assess the risk resulting from small tissue alpha-doses the toxicological, both human and animal, database was re-examined. The results of 20 epidemiological and toxicological studies with alpha-emitting radionuclides were analysed. In all cases a polynomial function provided a better fit to the data than a linear, no thresholds function. Also, in 19 cases a threshold dose below which no cancer is seen was indicated. The position of this threshold varied according to cancer type, but was typically in the range 0.1 to 1.0Gy of tissue dose - with a mean of 0.5Gy. It is concluded that alpha-radiation induced tumorogenesis is a threshold response and that as long as tissue doses are kept below these thresholds no additional cancers would be seen in either patients receiving alpha-therapy or in staff exposed to 'spilt' radionuclide. The presence of thresholds questions the appropriateness of current ALARA practices that are mostly used to drive occupational alpha-radiation exposures to as close to zero as possible. (author)

  3. Human cytogenetic dosimetry: a dose-response relationship for alpha particle radiation from 241Am

    International Nuclear Information System (INIS)

    DuFrain, R.J.; Littlefield, L.G.; Joiner, E.E.; Frome, E.L.

    1979-01-01

    Cytogenetic dosimetry estimates to guide treatment of persons internally contaminated with transuranic elements have not previously been possible because appropriate in vitro dose-response curves specifically for alpha particle irradiation of human lymphocytes do not exist. Using well-controlled cytogenetic methods for human lymphocyte culture, an experimentally derived dose-response curve for 241 Am alpha particle (5.49 and 5.44 MeV) radiation of G 0 lymphocytes was generated. Cells were exposed to 43.8, 87.7, 175.3 or 350.6 nCi/ml 241 Am for 1.7 hr giving doses of 0.85, 1.71, 3.42 or 6.84 rad. Based on dicentric chromosome yield, the linear dose-response equation is Y = 4.90(+-0.42) x 10 -2 X, with Y given as dicentrics per cell and X as dose in rads. The study also shows that the two-break asymmetrical exchanges in cells damaged by alpha particle radiation are overdispersed when compared to a Poisson distribution. An example is presented to show how the derived dose-response equation can be used to estimate the radiation dose for a person internally contaminated with an actinide. An experimentally derived RBE value of 118 at 0.85 rad is calculated for the efficiency of 241 Am alpha particle induction of dicentric chromosomes in human G 0 lymphocytes as compared with the efficiency of 60 Co gamma radiation. The maximum theoretical value for the RBE for cytogenetic damage from alpha irradiation was determined to be 278 at 0.1 rad or less which is in marked contrast to previously reported RBE values of approx. 20. (author)

  4. Cosmology from clustering of Lyman-alpha galaxies: breaking non-gravitational Lyman-alpha radiative transfer degeneracies using the bispectrum

    OpenAIRE

    Greig, Bradley; Komatsu, Eiichiro; Wyithe, J. Stuart B.

    2012-01-01

    Large surveys for Lyman-alpha emitting (LAE) galaxies have been proposed as a new method for measuring clustering of the galaxy population at high redshift with the goal of determining cosmological parameters. However, Lyman-alpha radiative transfer effects may modify the observed clustering of LAE galaxies in a way that mimics gravitational effects, potentially reducing the precision of cosmological constraints. For example, the effect of the linear redshift-space distortion on the power spe...

  5. Effect of polonium alpha-radiation on aqueous solutions (the history of French and Russian studies)

    International Nuclear Information System (INIS)

    Vladimirova, M.V.

    1998-01-01

    Since Pierre and Marie Curie's discovery of polonium and radium the effect of their radiation on chemical systems was noted. This gave rise to a new science - radiation chemistry. Systematic studies of radiation effects go back to the mid-1940s. The effect of gamma and x radiation was studied most, while only M. Curie's laboratory in France was concerned with alpha emitting polonium and radon. M. Haissinsky, M. Lefort, P. Bonet-Marry, M. Anta pioneered this activity. Radon was soon abandoned in favour of polonium recovered from RaD. With its short half-life, polonium is an ideal emitter which at its low content by weight produces a highly intensive radiation. French scientists determined radiation yields of H 2 , O 2 , H 2 O 2 and that of water radiolytic decomposition, G[-H 2 O]. The latter was found to be equal to 3.5 molecule/100 eV and much less than that from gamma radiolysis (4.2 molecule/100 eV). It should be noted that the polonium recovered from RaD contained a variety of impurities influencing the yield of radiolysis products formed. From the outset of her study in 1957, the author of this paper used the purest polonium recovered from reactor-irradiated Bi-209. This made it possible to define the yields from alpha radiolysis of various aqueous solutions more exactly. Relying on the J. Pucheault hypothesis concerning the decomposition of molecular radiolysis products in heavy particle tracks, author's efforts were directed toward the quantification of initial radiolysis yields. Special experiments have shown that G[-H 2 O] is much the same from alpha and gamma radiolysis (around 4.2 molecule/100eV). The author had the good luck to discuss her results with Pr. M. Haissinsky from Laboratory Curie. (author)

  6. Cranial nerve damage in patients after alpha (heavy)-particle radiation to the pituitary

    Energy Technology Data Exchange (ETDEWEB)

    Price, J.; Wei, W.C.; Chong, C.Y.

    1979-06-01

    The records of 161 patients were reviewed to determine if radiation damage had occurred following cranial irradiation. All of these patients had received alpha-particle radiation to their pituitary glands for diabetic retinopathy. Extraocular muscle palsy developed in 11 of these patients, iridoplegia in six, and fifth nerve damage in six. All of the palsies developed within a short period following their irradiation, and a definite dose relationship was present. The estimated doses to the third, fourth, fifth, and sixth cranial nerves was calculated at a saggital plane 13 to 15 mm from the pituitary by using computer-drawn dosimetry charts for the respective aperture size.

  7. Cranial nerve damage in patients after alpha (heavy)-particle radiation to the pituitary

    International Nuclear Information System (INIS)

    Price, J.; Wei, W.C.; Chong, C.Y.

    1979-01-01

    The records of 161 patients were reviewed to determine if radiation damage had occurred following cranial irradiation. All of these patients had received alpha-particle radiation to their pituitary glands for diabetic retinopathy. Extraocular muscle palsy developed in 11 of these patients, iridoplegia in six, and fifth nerve damage in six. All of the palsies developed within a short period following their irradiation, and a definite dose relationship was present. The estimated doses to the third, fourth, fifth, and sixth cranial nerves was calculated at a saggital plane 13 to 15 mm from the pituitary by using computer-drawn dosimetry charts for the respective aperture size

  8. A model for the stepwise radiation inactivation of the alpha 2-dimer of Na,K-ATPase

    Energy Technology Data Exchange (ETDEWEB)

    Norby, J.G.; Jensen, J. (Univ. of Aarhus (Denmark))

    1989-11-25

    This study is a direct continuation of Jensen, J., and Norby. A new model in which we propose that the in situ organization of the Na,K-ATPase alpha-subunit is an alpha 2-dimer and which describes the stepwise degradation by radiation inactivation of this assembly is presented on the basis of the following findings. Radiation inactivation size for alpha-peptide integrity, normal nucleotide, vanadate and ouabain binding, and K-pNPPase activity is close to m(alpha) = 112 kDa; for Na-ATPase activity it is 135 kDa and for Na,K-ATPase activity it increases from 140 to about 195 kDa with increasing assay ATP concentration (equal to increasing average turnover). Normal Tl+ occlusion had the same radiation inactivation size as Vmax for Na,K-ATPase, i.e. about 195 kDa. The binding experiments disclosed radiation-produced molecules with active binding sites but with a lower than normal affinity. Radiation inactivation size for the total binding capacity of ADP and ouabain was therefore smaller than the size of an alpha-peptide, namely about 70 kDa, and for total Tl+ occlusion it was down to 40 kDa. We can explain all these observations by using a new approach to target size analysis and by assuming a dimeric organization of the alpha-subunit. Each alpha-peptide is degraded stepwise by first destruction of either a 42- or a 70-kDa domain, and the partly damaged peptide may retain biochemical activity. We conclude that there is no role for the beta-subunit in catalysis and that the alpha-peptide is organized as an alpha 2-dimer in the membrane with each alpha-subunit being able to perform complete catalytic cycles (and probably also active transport), provided that it is stabilized by an adjacent alpha-peptide or a sufficiently large fragment thereof.

  9. A model for the stepwise radiation inactivation of the alpha 2-dimer of Na,K-ATPase

    International Nuclear Information System (INIS)

    Norby, J.G.; Jensen, J.

    1989-01-01

    This study is a direct continuation of Jensen, J., and Norby. A new model in which we propose that the in situ organization of the Na,K-ATPase alpha-subunit is an alpha 2-dimer and which describes the stepwise degradation by radiation inactivation of this assembly is presented on the basis of the following findings. Radiation inactivation size for alpha-peptide integrity, normal nucleotide, vanadate and ouabain binding, and K-pNPPase activity is close to m(alpha) = 112 kDa; for Na-ATPase activity it is 135 kDa and for Na,K-ATPase activity it increases from 140 to about 195 kDa with increasing assay ATP concentration (equal to increasing average turnover). Normal Tl+ occlusion had the same radiation inactivation size as Vmax for Na,K-ATPase, i.e. about 195 kDa. The binding experiments disclosed radiation-produced molecules with active binding sites but with a lower than normal affinity. Radiation inactivation size for the total binding capacity of ADP and ouabain was therefore smaller than the size of an alpha-peptide, namely about 70 kDa, and for total Tl+ occlusion it was down to 40 kDa. We can explain all these observations by using a new approach to target size analysis and by assuming a dimeric organization of the alpha-subunit. Each alpha-peptide is degraded stepwise by first destruction of either a 42- or a 70-kDa domain, and the partly damaged peptide may retain biochemical activity. We conclude that there is no role for the beta-subunit in catalysis and that the alpha-peptide is organized as an alpha 2-dimer in the membrane with each alpha-subunit being able to perform complete catalytic cycles (and probably also active transport), provided that it is stabilized by an adjacent alpha-peptide or a sufficiently large fragment thereof

  10. Alpha-risk: a European project on the quantification of risks associated with multiple radiation exposures

    International Nuclear Information System (INIS)

    Laurier, D.; Monchaux, G.; Tirmarche, M.; Darby, S.; Cardis, E.; Binks, K.; Hofmann, W.; Muirhead, C.

    2006-01-01

    The Alpha-Risk research project is being conducted within the Sixth European Framework Programme (EC-FP6, 2005 -2008). It aims to improve the quantification of risks associated with multiple exposures, taking into account the contribution of different radionuclides and external exposure using specific organ dose calculations. The Alpha-Risk Consortium involves 18 partners from 9 countries, and is coordinated by the IRSN. Its composition allows a multidisciplinary collaboration between researchers in epidemiology, dosimetry, statistics, modelling and risk assessment. Alpha-Risk brings together major epidemiological studies in Europe, which are able to evaluate long-term health effects of internal exposure from radionuclides. It includes large size cohort and case-control studies, with accurate registration of individual annual exposures: uranium miner studies, studies on lung cancer and indoor radon exposure, and studies of lung cancer and leukaemia among nuclear workers exposed to transuranic nuclides (mainly uranium and plutonium), for whom organ doses will be reconstructed individually. The contribution of experts in dosimetry will allow the calculation of organ doses in presence of multiple exposures (radon decay products, uranium dust and external gamma exposure). Expression of the risk per unit organ dose will make it possible to compare results with those from other populations exposed to external radiation. The multidisciplinary approach of Alpha-Risk promotes the development of coherent and improved methodological approaches regarding risk modelling. A specific work - package is dedicated to the integration of results and their use for risk assessment, especially for radon. Alpha-Risk will contribute to a better understanding of long-term health risks following chronic low doses from internal exposures. The project also has the great potential to help resolve major public health concerns about the effects of low and/or protracted exposures, especially

  11. Semi-Automatic Segmentation of Optic Radiations and LGN, and Their Relationship to EEG Alpha Waves.

    Directory of Open Access Journals (Sweden)

    Emmanuelle Renauld

    Full Text Available At rest, healthy human brain activity is characterized by large electroencephalography (EEG fluctuations in the 8-13 Hz range, commonly referred to as the alpha band. Although it is well known that EEG alpha activity varies across individuals, few studies have investigated how this may be related to underlying morphological variations in brain structure. Specifically, it is generally believed that the lateral geniculate nucleus (LGN and its efferent fibres (optic radiation, OR play a key role in alpha activity, yet it is unclear whether their shape or size variations contribute to its inter-subject variability. Given the widespread use of EEG alpha in basic and clinical research, addressing this is important, though difficult given the problems associated with reliably segmenting the LGN and OR. For this, we employed a multi-modal approach and combined diffusion magnetic resonance imaging (dMRI, functional magnetic resonance imaging (fMRI and EEG in 20 healthy subjects to measure structure and function, respectively. For the former, we developed a new, semi-automated approach for segmenting the OR and LGN, from which we extracted several structural metrics such as volume, position and diffusivity. Although these measures corresponded well with known morphology based on previous post-mortem studies, we nonetheless found that their inter-subject variability was not significantly correlated to alpha power or peak frequency (p >0.05. Our results therefore suggest that alpha variability may be mediated by an alternative structural source and our proposed methodology may in general help in better understanding the influence of anatomy on function such as measured by EEG or fMRI.

  12. Rapid appearance of transient secondary adrenocortical insufficiency after alpha-particle radiation therapy for Cushing's disease

    International Nuclear Information System (INIS)

    Cook, D.M.; Jordan, R.M.; Kendall, J.W.; Linfoot, J.A.

    1976-01-01

    A 17-year-old woman received 12,000 rads of alpha-particle radiation for the treatment of Cushing's disease. One day after the completion of therapy, the patient developed nausea, vomiting, headache, and postural hypotension. Laboratory evaluation demonstrated a marked fall of the previously elevated urinary 17-hydroxycorticosteroids (17-OHCS) and undetectable plasma cortisols. The urinary 17-OHCS transiently returned to supranormal levels but over a 2 1 / 2 -week period decreased and then remained low. The patient also demonstrated a subnormal urinary aldosterone excretion in relation to plasma renin activity (PRA) during 10 mEq/24 h sodium restriction. The remainder of the endocrine evaluation was normal, suggesting that pituitary function otherwise remained intact. One and one-half years after alpha-particle therapy, the patient's urinary 17-OHCS were normal and responded normally to metyrapone. The relationship between urinary aldosterone excretion and PRA also was normal. It is postulated that there was an infarction of an ACTH secreting pituitary tumor leaving the remainder of the pituitary intact. A chronically elevated circulating level of ACTH with sudden loss of ACTH secretion appeared to have been responsible for the initial low urinary aldosterone as well as the low urinary 17-OHCS. This is the first reported case of a presumed pituitary tumor infarction in association with alpha-particle pituitary radiation

  13. Polar solar wind and interstellar wind properties from interplanetary Lyman-alpha radiation measurements

    Science.gov (United States)

    Witt, N.; Blum, P. W.; Ajello, J. M.

    1981-01-01

    The analysis of Mariner 10 observations of Lyman-alpha resonance radiation shows an increase of interplanetary neutral hydrogen densities above the solar poles. This increase is caused by a latitudinal variation of the solar wind velocity and/or flux. Using both the Mariner 10 results and other solar wind observations, the values of the solar wind flux and velocity with latitude are determined for several cases of interest. The latitudinal variation of interplanetary hydrogen gas, arising from the solar wind latitudinal variation, is shown to be most pronounced in the inner solar system. From this result it is shown that spacecraft Lyman-alpha observations are more sensitive to the latitudinal anisotropy for a spacecraft location in the inner solar system near the downwind axis.

  14. Trans-generational effects induced by alpha and gamma ionizing radiations at Daphnia magna

    International Nuclear Information System (INIS)

    Parisot, Florian

    2015-01-01

    Anthropogenic activities related to the nuclear industry contribute to continuous discharges of radionuclides into terrestrial and aquatic ecosystems. Over the past decades, the ecological risk of ionizing radiation has become a growing public, regulatory and scientific concern for ecosystems protection. Until recently, only few studies focus on exposure situations at low doses of irradiation, although these situations are representative of realistic environmental conditions. Understanding how ionizing radiation affects species over several generations and at various levels of biological organization is a major research goal in radioecology. The aim of this PhD was to bring new knowledge on the effects of ionizing radiation during a multi-generational expose of the aquatic invertebrate, Daphnia magna. A two-step strategy was implemented. First, an external gamma radiation at environmentally relevant dose rates was performed on D. magna over three successive generations (F0, F1 and F2). The objective of this experiment was to examine whether low dose rates of radiation induced increasing effects on survival, growth and reproduction of daphnids over generations and to test a possible accumulation and transmission of DNA alterations from adults to offspring. Results showed an accumulation and a transmission of DNA alterations over generations, together with an increase in effect severity on growth and reproduction from generation F0 to generation F2. Transiently more efficient DNA repair leading to some recovery at the organism level was suggested in generation F1. Second, data from the external gamma irradiation and those from an earlier study of internal alpha contamination were analyzed with DEBtox models (Dynamic Energy Budget applied to toxicology), to identify and compare the causes of the trans-generational increase in effect severity between the two types of radiation. In each case, two distinct metabolic modes of action were necessary to explain effects on

  15. Scintillator assembly for alpha radiation detection and an associated method of making

    Science.gov (United States)

    Lauf, R.J.; McElhaney, S.A.; Bates, J.B.

    1994-07-26

    A scintillator assembly for use in conjunction with a photomultiplier or the like in the detection of alpha radiation utilizes a substrate or transparent yttrium aluminum garnet and a relatively thin film of cerium-doped yttrium aluminum garnet coated upon the substrate. The film material is applied to the substrate in a sputtering process, and the applied film and substrate are annealed to effect crystallization of the film upon the substrate. The resultant assembly provides relatively high energy resolution during use in a detection instrument and is sufficiently rugged for use in field environments. 4 figs.

  16. Nanodosimetry and nanodosimetric-based models of radiation action for radon alpha particles. Final performance technical report

    International Nuclear Information System (INIS)

    Zaider, M.

    1997-01-01

    The goal of this project was to develop theoretical/computational tools for evaluating the risks incurred by populations exposed to radon alpha particles. Topics of concern include the following: compound dual radiation action (general aspects); a mathematical formalism describing the yield of radiation induced single-and double-strand DNA breaks, and its dependence on radiation quality; a study of the excited states in cytosine and guanine stacks in the Hartree-Fock and exciton approximations; nanodosimetry of radon alpha particles; application of the HSEF to assessing radiation risks in the practice of radiation protection; carcinogenic risk coefficients at environmental levels of radon exposures: a microdosimetric approach; and hit-size effectiveness approach in radiation protection

  17. Resonance-enhanced two-photon ionization of ions by Lyman alpha radiation in gaseous nebulae.

    Science.gov (United States)

    Johansson, S; Letokhov, V

    2001-01-26

    One of the mysteries of nebulae in the vicinity of bright stars is the appearance of bright emission spectral lines of ions, which imply fairly high excitation temperatures. We suggest that an ion formation mechanism, based on resonance-enhanced two-photon ionization (RETPI) by intense H Lyman alpha radiation (wavelength of 1215 angstroms) trapped inside optically thick nebulae, can produce these spectral lines. The rate of such an ionization process is high enough for rarefied gaseous media where the recombination rate of the ions formed can be 10(-6) to 10(-8) per second for an electron density of 10(3) to 10(5) per cubic centimeter in the nebula. Under such conditions, the photo-ions formed may subsequently undergo further RETPI, catalyzed by intense He i and He ii radiation, which also gets enhanced in optically thick nebulae that contain enough helium.

  18. Wandering in the Lyman-alpha forest: a study of dark matter-dark radiation interactions

    International Nuclear Information System (INIS)

    Krall, Rebecca; Cyr-Racine, Francis-Yan; Dvorkin, Cora

    2017-01-01

    The amplitude of large-scale matter fluctuations inferred from the observed Sunyaev-Zeldovich (SZ) cluster mass function and from weak gravitational lensing studies, when taken at face value, is in tension with measurements of the cosmic microwave background (CMB) and baryon acoustic oscillation (BAO). In this work, we revisit whether this possible discrepancy can be attributed to new interactions in the dark matter sector. Focusing on a cosmological model where dark matter interacts with a dark radiation species until the epoch of matter-radiation equality, we find that measurements of the Lyman-alpha flux power spectrum from the Sloan Digital Sky Survey provide no support to the hypothesis that new dark matter interactions can resolve the possible tension between CMB and large-scale structure (LSS). Indeed, while the addition of dark matter-dark radiation interactions leads to an improvement of 2ΔlnL=12 with respect to the standard Λ cold dark matter (ΛCDM) model when only CMB, BAO, and LSS data are considered, the inclusion of Lyman-alpha data reduces the improvement of the fit to 2ΔlnL=6 relative to ΛCDM . We thus conclude that the statistical evidence for new dark matter interactions (largely driven by the Planck SZ dataset) is marginal at best, and likely caused by systematics in the data. We also perform a Fisher forecast analysis for the reach of a future dataset composed of a CMB-S4 experiment combined with the Large Synoptic Survey Telescope galaxy survey. We find that the constraint on the effective number of fluid-like dark radiation species, Δ N fluid , will be improved by an order of magnitude compared to current bounds.

  19. Effect of long-term exposure to mobile phone radiation on alpha-Int1 gene sequence of Candida albicans

    Science.gov (United States)

    Shahin-jafari, Ariyo; Bayat, Mansour; Shahhosseiny, Mohammad Hassan; Tajik, Parviz; Roudbar-mohammadi, Shahla

    2015-01-01

    Over the last decade, communication industries have witnessed a tremendous expansion, while, the biological effects of electromagnetic waves have not been fully elucidated. Current study aimed at evaluating the mutagenic effect of long-term exposure to 900-MHz radiation on alpha-Int1 gene sequences of Candida albicans. A standard 900 MHz radiation generator was used for radiation. 10 ml volumes from a stock suspension of C. albicans were transferred into 10 polystyrene tubes. Five tubes were exposed at 4 °C to a fixed magnitude of radiation with different time periods of 10, 70, 210, 350 and 490 h. The other 5 tubes were kept far enough from radiation. The samples underwent genomic DNA extraction. PCR amplification of alpha-Int1 gene sequence was done using one set of primers. PCR products were resolved using agarose gel electrophoresis and the nucleotide sequences were determined. All samples showed a clear electrophoretic band around 441 bp and further sequencing revealed the amplified DNA segments are related to alpha-Int1 gene of the yeast. No mutations in the gene were seen in radiation exposed samples. Long-term exposure of the yeast to mobile phone radiation under the above mentioned conditions had no mutagenic effect on alpha-Int1 gene sequence. PMID:27081370

  20. Matlab fractal techniques used to study the structural degradation caused by alpha radiation to laser mirrors

    Science.gov (United States)

    Ioan, M.-R.

    2018-01-01

    Almost all optical diagnostic systems associated with classical particle accelerators or with new state-of-the-art particle accelerators, such as those developed within the European Collaboration ELI-NP (Extreme Light Infrastructure-Nuclear Physics) (involving extreme power laser beams), contain in their infrastructure high quality laser mirrors, used for their reflectivity and/or their partial transmittance. These high quality mirrors facilitate the extraction and handling of optical signals. When optical mirrors are exposed to high energy ionizing radiation fields, their optical and structural properties will change over time and their functionality will be affected, meaning that they will provide imprecise information. In some experiments, being exposed to mixed laser and accelerated particle beams, the deterioration of laser mirrors is even more acute, since the destruction mechanisms of both types of beams are cumulated. The main task of the work described in this paper was to find a novel specific method to analyse and highlight such degradation processes. By using complex fractal techniques integrated in a MATLAB code, the effects induced by alpha radiation to laser mirrors were studied. The fractal analysis technique represents an alternative approach to the classical Euclidean one. It can be applied for the characterization of the defects occurred in mirrors structure due to their exposure to high energy alpha particle beams. The proposed method may be further integrated into mirrors manufacturing process, as a testing instrument, to obtain better quality mirrors (enhanced resistance to high energy ionizing beams) by using different types of reflective coating materials and different deposition techniques. Moreover, the effect of high energy alpha ionizing particles on the optical properties of the exposed laser mirrors was studied by using spectrophotometric techniques.

  1. Alpha-tocopherol succinate- and AMD3100-mobilized progenitors mitigate radiation combined injury in mice

    International Nuclear Information System (INIS)

    Singh, Vijay K.; Wise, Stephen Y.; Fatanmi, Oluseyi O.; Beattie, Lindsay A.; Ducey, Elizabeth J.; Seed, Thomas M.

    2014-01-01

    The purpose of this study was to elucidate the role of alpha-tocopherol succinate (TS)- and AMD3100-mobilized progenitors in mitigating combined injury associated with acute radiation exposure in combination with secondary physical wounding. CD2F1 mice were exposed to high doses of cobalt-60 gamma-radiation and then transfused intravenously with 5 million peripheral blood mononuclear cells (PBMCs) from TS- and AMD3100-injected mice after irradiation. Within 1 h after irradiation, mice were exposed to secondary wounding. Mice were observed for 30 d after irradiation and cytokine analysis was conducted by multiplex Luminex assay at various time-points after irradiation and wounding. Our results initially demonstrated that transfusion of TS-mobilized progenitors from normal mice enhanced survival of acutely irradiated mice exposed 24 h prior to transfusion to supralethal doses (11.5–12.5 Gy) of 60 Co gamma-radiation. Subsequently, comparable transfusions of TS-mobilized progenitors were shown to significantly mitigate severe combined injuries in acutely irradiated mice. TS administered 24 h before irradiation was able to protect mice against combined injury as well. Cytokine results demonstrated that wounding modulates irradiation-induced cytokines. This study further supports the conclusion that the infusion of TS-mobilized progenitor-containing PBMCs acts as a bridging therapy in radiation-combined-injury mice. We suggest that this novel bridging therapeutic approach involving the infusion of TS-mobilized hematopoietic progenitors following acute radiation exposure or combined injury might be applicable to humans. (author)

  2. Surface effect of ultraviolet radiation on electrochemically etched alpha-particle tracks in PADC

    International Nuclear Information System (INIS)

    Ng, F.M.F.; Tse, K.C.C.; Nikezic, D.; Dai, Junfeng; Zhao, Ziqiang; Yu, K.N.

    2008-01-01

    The size of alpha-particle tracks on electrochemically etched ultraviolet-irradiated polyallyldiglycol carbonate (PADC) films were studied. PADC films were first irradiated with 3 MeV alpha particles and then pre-etched chemically using aqueous 6.25 N NaOH solution for 2 h. The films were then exposed to incoherent broad-band ultraviolet (UV) radiation provided by a mercury lamp for different durations up to 2 h. The films were then electrochemically etched in a 6.25 N NaOH solution, with an a.c. voltage of about 1200 V eff and a frequency of 5 kHz, for 2 h at room temperature. The mean sizes of the tracks (or trees) were measured and were found to increase for short UV exposures and decrease for prolonged UV exposures. The results can be explained by the dominance of chain scission at the beginning of UV exposure and the dominance of cross linking for prolonged UV exposure. This explanation is further supported by results from X-ray photo-electron spectroscopy (XPS). Here, the C-O-C bonds decrease for short UV exposures, which is explained by scission of the polymer chains, and increase again for prolonged UV exposure, which indicates cross linking. From nano-indentation measurements, the hardness and the reduced modulus increase monotonically with the UV irradiation. Apparently, these quantities only characterize the amount of cross linking, and do not give information on the initial scission process

  3. Protective Role of Alpha Lipoic Acid Against Disorders Induced by Gamma Radiation

    International Nuclear Information System (INIS)

    Abd El Azeem, Kh.N.M.

    2011-01-01

    Ionizing radiation interacts with living cells, causing a variety of biochemical changes depending on exposed and absorbed doses, duration of exposure, interval after exposure and susceptibility of tissues to ionizing radiation. So, it may increase the oxidative stress and damage of body organs. Alpha-lipoic acid (ALA-also known as thioctic acid) appears to be readily absorbed from an oral dose and converts easily to its reduced form, dihydro lipoic acid (DHLA), in many tissues of the body. ALA can neutralize free radicals in both fatty and watery regions of cells. The present study has been designed to evaluate the possible efficiency of ALA as antioxidant and radio-protector against radiation induced oxidative stress in different organs (liver, kidney and heart) in rats through estimation of the activity of markers of serum liver, kidney and heart function, in addition to the histopathological differentiation of these organs by light and electron microscope. Five equal groups were conducted for the study: control, ALA (30 mg/kg body wt), irradiated (each rat was exposed to 6 Gy as a fractionated dose of gamma (γ) radiation), irradiated plus ALA (each rat received ALA for 9 days simultaneously during exposure) and ALA plus irradiation plus ALA groups (each rat received ALA for a week pre-exposure plus 9 days during exposure). Radiation doses were fractionated dose levels of 2 Gy each 3 days to reach accumulative dose of 6 Gy. After 3 days of each exposure rats were sacrificed, except, those left for recovery test one month after last exposure. The results revealed that whole body γ-irradiation of rats induces oxidative stress in liver, kidney and heart obviously manifested by significant elevation in alanine and aspartate transaminase ( ALT and AST), alkaline phosphatase (ALP), urea, creatinine and creatine kinase (CK-MB). ALA treated-irradiated rats showed lower significantly values indicating remarkable improvement in all measured parameters and

  4. SU-C-303-02: Correlating Metabolic Response to Radiation Therapy with HIF-1alpha Expression

    Energy Technology Data Exchange (ETDEWEB)

    Campos, D [University of Wisconsin Madison, Madison, WI (United States); Peeters, W [Radboud University Medical Center, Nijmegen, GA (United States); Nickel, K [University of Wisconsin, Madison, WI (United States); Eliceiri, K; Kimple, R; Van Der Kogel, A; Kissick, M [University of Wisconsin, Madison, Wisconsin (United States)

    2015-06-15

    Purpose: To understand radiation induced alterations in cellular metabolism which could be used to assess treatment or normal tissue response to aid in patient-specific adaptive radiotherapy. This work aims to compare the metabolic response of two head and neck cell lines, one malignant (UM-SCC-22B) and one benign (Normal Oral Keratinocyte), to ionizing radiation. Responses are compared to alterations in HIF-1alpha expression. These dynamics can potentially serve as biomarkers in assessing treatment response allowing for patient-specific adaptive radiotherapy. Methods: Measurements of metabolism and HIF-1alpha expression were taken before and X minutes after a 10 Gy dose of radiation delivered via an orthovoltage x-ray source. In vitro changes in metabolic activity were measured via fluorescence lifetime imaging (FLIM) to assess the mean lifetime of NADH autofluorescence following a dose of 10 Gy. HIF-1alpha expression was measured via immunohistochemical staining of in vitro treated cells and expression was quantified using the FIJI software package. Results: FLIM demonstrated a decrease in the mean fluorescence lifetime of NADH by 100 ps following 10 Gy indicating a shift towards glycolytic pathways for malignant cells; whereas this benign cell line showed little change in metabolic signature. Immunohistochemical analysis showed significant changes in HIF-1alpha expression in response to 10 Gy of radiation that correlate to metabolic profiles. Conclusion: Radiation induces significant changes in metabolic activity and HIF-1alpha expression. These alterations occur on time scales approximating the duration of common radiation treatments (approximately tens of minutes). Further understanding these dynamics has important implications with regard to improvement of therapy and biomarkers of treatment response.

  5. Study of alpha-tocopherol as a protector of damages induced to the skin by ionizing radiation

    International Nuclear Information System (INIS)

    Lucero, M.J.; Vigo, J.; Leon, M.J.; Sanchez, J.A.; Martin, F.

    1997-01-01

    An experimental study was carried out in animals for determining the characteristics of alpha-tocopherol protection against lesions caused by free radicals produced by ionizing radiation. Two different concentrations of alpha-tocopherol were applied on the same exposed sample. A linear electron accelerator of 6 MeV was used for the production of free radicals and a dose of 2800 cGy. The lesions were submitted to clinical studies for anatomic pathologies. The conclusion of this study is that alpha-tocopherol applied to skin before and immediately after the exposure to ionizing radiation has the capability to protect it, developing a perfectly differentiated epidermis and of greater thickness than normally considered

  6. Generation of continuous coherent radiation at Lyman-alpha and 1S-2P Spectroscopy of atomic hydrogen

    NARCIS (Netherlands)

    Pahl, A.; Fendel, P.; Henrich, B.R.; Walz, J.; Hansch, T.W.; Eikema, K.S.E.

    2005-01-01

    Continuous coherent radiation from wavelengths from 121 to 123 nm in the vacuum ultraviolet (VUV) was generated by four-wave sum-frequency mixing in mercury vapor. A yield of 20 nW at Lyman-alpha (121.57 nm) was achieved. We describe the experimental setup in detail and present a calculation of the

  7. Response of tumour necrosis factor alpha (TNF ) in blood and spleen mice that vaccinated with P.berghei radiation

    International Nuclear Information System (INIS)

    Darlina; Tur R; Teja K

    2015-01-01

    Tumor necrosis factor is a glycoprotein derived from helper T lymphocytes that play an important role in the body's response against malaria infection. However, TNF-α has double play that is on appropriate levels will provide protection and healing, while at excessive levels which may be a response to hyperparasitemia. Thus investigated the expression of TNF alpha secreted blood lymphocytes and spleen cells the mice that's infected with 1 x 10 7 P.berghei infectious or inactivated by radiation. Levels of TNF alpha serum and spleen cell culture medium was monitored on days 2, 7, 14 post infection. Monitoring of parasite growth every two days for 60 days. Determination of TNF alpha levels were measure using ELISA. The results showed parasitaemia mice infected with 175 Gy irradiated parasites have pre patent period of 16 days longer than the control (non-irradiated parasites) with low parasitaemia. TNF alpha concentration that secreted spleen cells of mice vaccinated higher than control mice. Concentration of TNF alpha that secreted blood lymphocyte of mice vaccinated lower than control mice. It was concluded that the secretion of TNF alpha by blood lymphocytes caused more pathogenic factors of the parasite, while the secretion of TNF alpha in spleen due to an immune response against the parasite. (author)

  8. Dosimetric characterization of BeO samples in alpha, beta and X radiation beams using luminescent techniques

    International Nuclear Information System (INIS)

    Groppo, Daniela Piai

    2013-01-01

    In the medical field, the ionizing radiation is used both for therapeutic and diagnostic purposes, in a wide range of radiation doses. In order to ensure that the objective is achieved in practice, detailed studies of detectors and devices in different types of radiations beams are necessary. In this work a dosimetric characterization of BeO samples was performed using the techniques of thermoluminescence (TL) and optically stimulated luminescence (OSL) by a comparison of their response for alpha, beta and X radiations and the establishment of an appropriated system for use in monitoring of these radiations beams. The main results are: the high sensitivity to beta radiation for both techniques, good reproducibility of TL and OSL response (coefficients of variation lower than 5%), maximum energy dependence of the X radiation of 28% for the TL technique, and only 7% for the OSL technique, within the studied energy range. The dosimetric characteristics obtained in this work show the possibility of applying BeO samples to dosimetry of alpha, beta and X radiations, considering the studied dose ranges, using the TL and OSL techniques. From the results obtained, the samples of BeO showed their potential use for beam dosimetry in diagnostic radiology and radiotherapy. (author)

  9. Calculation of the Electronic Parameters of an Al/DNA/p-Si Schottky Barrier Diode Influenced by Alpha Radiation

    Directory of Open Access Journals (Sweden)

    Hassan Maktuff Jaber Al-Ta'ii

    2015-02-01

    Full Text Available Many types of materials such as inorganic semiconductors have been employed as detectors for nuclear radiation, the importance of which has increased significantly due to recent nuclear catastrophes. Despite the many advantages of this type of materials, the ability to measure direct cellular or biological responses to radiation might improve detector sensitivity. In this context, semiconducting organic materials such as deoxyribonucleic acid or DNA have been studied in recent years. This was established by studying the varying electronic properties of DNA-metal or semiconductor junctions when exposed to radiation. In this work, we investigated the electronics of aluminium (Al/DNA/silicon (Si rectifying junctions using their current-voltage (I-V characteristics when exposed to alpha radiation. Diode parameters such as ideality factor, barrier height and series resistance were determined for different irradiation times. The observed results show significant changes with exposure time or total dosage received. An increased deviation from ideal diode conditions (7.2 to 18.0 was observed when they were bombarded with alpha particles for up to 40 min. Using the conventional technique, barrier height values were observed to generally increase after 2, 6, 10, 20 and 30 min of radiation. The same trend was seen in the values of the series resistance (0.5889–1.423 Ω for 2–8 min. These changes in the electronic properties of the DNA/Si junctions could therefore be utilized in the construction of sensitive alpha particle detectors.

  10. The radiolysis of CMPO: effects of acid, metal complexation and alpha vs. gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bruce J. Mincher; Stephen P. Mezyk; Gary S. Groenewold

    2016-05-01

    Abstract The group actinide/lanthanide complexing agent octylphenylcarbamoylmethyl phosphine oxide (CMPO) has been examined for its radiation stability by measuring the kinetics of its reactions with free radicals in both the aqueous and organic phases for the free and metal-complexed ligand, identifying its degradation products for both alpha and gamma irradiation, measuring the effects on solvent extraction performance, and measuring the G-values for its degradation under various conditions. This includes the G-values for CMPO in the absence of, and in contact with the acidic aqueous phase, where it is shown that the acidic aqueous phase provides radio-protection for this ligand. It was found that both solvent and metal complexation affect the kinetics of the reaction of the •NO3 radical, a product of HNO3 radiolysis, with CMPO. For example, CMPO complexed with lanthanides has a rate constant for this reaction an order of magnitude higher than for the free ligand, and the reaction for the free ligand in the organic phase is about three times faster than in the aqueous phase. In steady state radiolysis kinetics it was determined that HNO3, although not NO3- anion, provides radio-protection to CMPO, with the G-value for its degradation decreasing with increasing acidity, until it was almost completely suppressed by irradiation in contact with 5 M HNO3. The same degradation products were produced by irradiation with alpha and gamma-sources, except that the relative abundances of these products varied. For example, the product of C-C bond scission was produced only in low amounts for gamma-radiolysis, but it was an important product for samples irradiated with a He ion beam. These results are compared to the new data appearing in the literature on DGA radiolysis, since CMPO and the DGAs both contain the amide functional group.

  11. Telomere Length in Aged Mayak PA Nuclear Workers Chronically Exposed to Internal Alpha and External Gamma Radiation.

    Science.gov (United States)

    Scherthan, Harry; Sotnik, Natalia; Peper, Michel; Schrock, Gerrit; Azizova, Tamara; Abend, Michael

    2016-06-01

    Telomeres consist of GC-rich DNA repeats and the "shelterin" protein complex that together protect chromosome ends from fusion and degradation. Telomeres shorten with age due to incomplete end replication and upon exposure to environmental and intrinsic stressors. Exposure to ionizing radiation is known to modulate telomere length. However, the response of telomere length in humans chronically exposed to radiation is poorly understood. Here, we studied relative telomere length (RTL) by IQ-FISH to leukocyte nuclei in a group of 100 workers from the plutonium production facility at the Mayak Production Association (PA) who were chronically exposed to alpha-emitting ((239)Pu) radiation and/or gamma (photon) radiation, and 51 local residents serving as controls, with a similar mean age of about 80 years. We applied generalized linear statistical models adjusted for age at biosampling and the second exposure type on a linear scale and observed an age-dependent telomere length reduction. In those individuals with the lowest exposure, a significant reduction of about 20% RTL was observed, both for external gamma radiation (≤1 Gy) and internal alpha radiation (≤0.05-0.1 Gy to the red bone marrow). In highly exposed individuals (>0.1 Gy alpha, 1-1.5 Gy gamma), the RTL was similar to control. Stratification by gender revealed a significant (∼30%) telomere reduction in low-dose-exposed males, which was absent in females. While the gender differences in RTL may reflect different working conditions, lifestyle and/or telomere biology, absence of a dose response in the highly exposed individuals may reflect selection against cells with short telomeres or induction of telomere-protective effects. Our observations suggest that chronic systemic exposure to radiation leads to variable dose-dependent effects on telomere length.

  12. Variance of the number of tumors in a model for the induction of osteosarcoma by alpha radiation

    International Nuclear Information System (INIS)

    Groer, P.G.; Marshall, J.H.

    1976-01-01

    An earlier report on a model for the induction of osteosarcoma by alpha radiation gave differential equations for the mean numbers of normal, transformed, and malignant cells. In this report we show that for a constant dose rate the variance of the number of cells at each stage and time is equal to the corresponding mean, so the numbers of tumors predicted by the model have a Poisson distribution about their mean values

  13. Determination of the efficiency variation with the alpha and beta radiation energies for a hands and feet circulating gas proportional detector system

    International Nuclear Information System (INIS)

    Morgado, M.M.; Moraes, M.A.P.V. de

    1994-01-01

    The alpha and beta efficiency calibrations of a gas flow detector have been performed in the energy range of 3-5.5 MeV for alpha radiation and 0.1-1.5 MeV for beta radiation. This detector is being used for laboratorial monitoring in a hand and foot monitor system. The results obtained showed a strong increase in efficiency as the alpha (α) energy or beta (β) energy increase. Values of efficiency 2-4 times larger were obtained in these energy ranges. (author). 5 refs, 2 figs, 4 tabs

  14. Analysis of radiation risk from alpha particle component of solar particle events

    Science.gov (United States)

    Cucinotta, F. A.; Townsend, L. W.; Wilson, J. W.; Golightly, M. J.; Weyland, M.

    1994-01-01

    The solar particle events (SPE) will contain a primary alpha particle component, representing a possible increase in the potential risk to astronauts during an SPE over the often studied proton component. We discuss the physical interactions of alpha particles important in describing the transport of these particles through spacecraft and body shielding. Models of light ion reactions are presented and their effects on energy and linear energy transfer (LET) spectra in shielding discussed. We present predictions of particle spectra, dose, and dose equivalent in organs of interest for SPE spectra typical of those occurring in recent solar cycles. The large events of solar cycle 19 are found to have substantial increase in biological risk from alpha particles, including a large increase in secondary neutron production from alpha particle breakup.

  15. Effect of alpha and gamma radiation on the near-field chemistry and geochemistry of high-level waste packages

    International Nuclear Information System (INIS)

    Reed, D.T.

    1985-12-01

    Ionizing radiation can potentially alter geochemical and chemical processes in a geologic system. These effects can either enhance or reduce the performance of the waste package in a deep geologic repository. Current indications are that, in a repository located in basalt, ionizing radiation significantly affects geochemical/chemical processes but does not appear to significantly affect factors important to the long-term performance of the repository. The experimental results presented in this paper were obtained as part of an ongoing effort by the Basalt Waste Isolation Project to determine the effect of ionizing radiation on chemical and geochemical processes in the environment of the waste package. Gamma radiolysis experiments were done by subjecting samples of synthetic basalt groundwater in the presence of various waste package components (basalt/packing/low-carbon steel) to high levels of gamma radiation from a 60 Co source. Post-irradiation analysis was done on the gas, liquid, and solid components of the basalt system. The results obtained are important in evaluating waste package performance during the containment period. The effect of alpha radiation on the basalt groundwater system in the presence of waste package components is important in evaluating waste package performance during the isolation period. The experimental work in this area is in a very preliminary stage. Results from two experiments are reported. 9 refs., 4 figs., 7 tabs

  16. DEVELOPMENT OF AN ON-LINE, REAL-TIME ALPHA RADIATION MEASURING INSTRUMENT FOR LIQUID STREAMS

    International Nuclear Information System (INIS)

    Unknown

    1999-01-01

    The US Department of Energy (DOE) has expressed a need for an on-line, real-time instrument for assaying alpha-emitting radionuclides (uranium and the transuranics) in effluent waters leaving DOE sites to ensure compliance with regulatory limits. Due to the short range of alpha particles in water (approximately40 Im), it is necessary now to intermittently collect samples of water and send them to a central laboratory for analysis. A lengthy and costly procedure is used to separate and measure the radionuclides from each sample. Large variations in radionuclide concentrations in the water may go undetected due to the sporadic sampling. Even when detected, the reading may not be representative of the actual stream concentration. To address these issues, the Advanced Technologies Group of Thermo Power Corporation (a Thermo Electron company) is developing a real-time, field-deployable alpha monitor based on a solid-state silicon wafer semiconductor (US Patent 5,652,013 and pending, assigned to the US Department of Energy). The Thermo Water Alpha Monitor will serve to monitor effluent water streams (Subsurface Contaminants Focus Area) and will be suitable for process control of remediation as well as decontamination and decommissioning (D and D) operations, such as monitoring scrubber or rinse water radioactivity levels (Mixed Waste, Plutonium, and D and D Focus Area). It would be applicable for assaying other liquids, such as oil, or solids after proper preconditioning. Rapid isotopic alpha air monitoring is also possible using this technology. This report details the program's accomplishments to date. Most significantly, the Alpha Monitoring Instrument was successfully field demonstrated on water 100X below the Environmental Protection Agency's proposed safe drinking water limit--down to under 1 pCi/1. During the Field Test, the Alpha Monitoring Instrument successfully analyzed isotopic uranium levels on a total of five different surface water, process water, and

  17. Effects of alpha radiation on plutonium incorporated in dosimetric materials by ESR studies

    International Nuclear Information System (INIS)

    Bhide, M.K.; Kadam, R.M.; Mohapatra, Manoj; Godbole, S.V.

    2007-01-01

    The in situ alpha irradiation effects of some ESR dosimetric materials namely alanine, 2-methyl alanine and ammonium tartrate were studied by incorporating 1% plutonium by weight in them. The radical intensity was monitored as a function of alpha dose. It was found that in the dose region 1-35 kGy ammonium tartrate showed better signal intensity, linearity and dose response as compared to the other materials. This was attributed to the single radical produced in case of the tartrate giving a sharp spectrum and the fast relaxation times owing to less saturation of ESR signals. (author)

  18. DEVELOPMENT OF AN ON-LINE, REAL-TIME ALPHA RADIATION MEASURING INSTRUMENT FOR LIQUID STREAMS

    International Nuclear Information System (INIS)

    Unknown

    1999-01-01

    Thermo Power Corporation has proven the technical viability of an on-line, real-time alpha radionuclide instrument for aqueous sample analysis through laboratory and initial field tests of the instrument. The instrument has been shown to be isotonically sensitive to extremely low (ten parts per trillion, or femto Curies per liter) levels of a broad range of radioisotopes. Performance enhancement and other scaling data obtained during the course of this investigation have shown that on-line, real-time operation is possible, with a sub 30-minute response time analyzing 20 ppb (30 pCi/1) natural uranium. Now that these initial field tests in Oak Ridge, Tennessee have been successfully completed, Thermo Power plans to conduct comprehensive field tests of the instrument. The purpose of these endurance tests will be to determine the endurance characteristics of the Thermo Alpha Monitor for Water when it is used by non-Thermo Power personnel in a series of one or more extended field tests. Such endurance testing is the vital next step towards the commercialization of the Alpha Monitor. Subsequently, it will be possible to provide the DOE with an instrument that has the capability of obtaining rapid feedback about the concentrations of alpha-emitting isotope contamination in effluent water streams (Subsurface Contaminants Focus Area). It will also be useful for process control of remediation and D and D operations such as monitoring scrubber/rinse water radioactivity levels (Mixed Waste, Plutonium and D and D Focus Areas)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-02-01

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

  20. Radiation and biophysical studies on cells and viruses. Progress report, April 1, 1976--June 30, 1977. [Gamma radiation, alpha particles

    Energy Technology Data Exchange (ETDEWEB)

    Cole, A.

    1977-01-01

    Progress is reported on the following research projects: genetic structure of DNA, chromosomes, and nucleoproteins; particle beam studies of radiosensitive sites; division delay in CHO cells induced by partly penetrating alpha particles; location of cellular sites for mutation induction; sites for radioinduced cell transformation using partly penetrating particle beams; gamma-ray and particle irradiation of nucleoproteins and other model systems; quantitation of surface antigens on normal and neoplastic cells by x-ray fluorescence; hyperthermic effects on cell survival and DNA repair mechanisms; and studies on radioinduced cell transformation. (HLW)

  1. TNF-alpha induced junctional modulation enhances response to radiation in Caco-2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Yeonjoo; Ahn, Hyein; Park, Jina; Lee, Byungryong; Chung, Eunkyung [Hallym University, Seoul (Korea, Republic of); Yi, Jaeoun [KIRAMS, Seoul (Korea, Republic of)

    2007-10-15

    The Adhesion molecules mediated cell-cell and cell matrix interactions are essential for variety of physiological and pathological processes including maintenance of normal tissues integrity as well as tumor development and progression. Cell-cell interaction is initiated by interactions of tight junctional proteins with neighboring cells. Tight junctions govern the paracellular permeability of endothelial and epithelial cells. Aberrations of tight junction formation are an early and key event during vascular spread cancer and inflammation. TNF-alpha plays an important role in the intestinal inflammation by increase of intestinal epithelial tight junction permeability. It has been reported that TNF alpha- modulated intestinal epithelial tight junction barrier is mediated by myosin light-chain kinase protein expression through NFk-B activation. However, the alterations of tight junctional proteins involved in the TNF-alpha-induced increase of intestinal TJ permeability remain unclear. Claudin is essential to the formation and maintenance of tight junction (TJ) and has been identified 24 members so far. Claudin-1, 3, 4, 6, 10 and 16 have been shown altered in various cancers and they may have important roles in cell survival, motility, and invasion of cancer cells. However, the functions of these proteins in tumorigenesis and inflammation are still being elucidated.

  2. Role of DNA polymerase. cap alpha. in chromosomal aberration production by ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bender, M.A.

    1983-01-01

    Aphidicolin is a tetracyclic diterpinoid fungal antibiotic which inhibits DNA synthesis in eukaryotic cells by interfering specifically with DNA polymerase ..cap alpha.., apparently by binding to and inactivating the DNA-polymerase ..cap alpha.. complex. We have shown that aphidicolin, like other inhibitors of DNA synthesis, both induces chromosomal aberrations in human peripheral lymphocytes, and, as a post-treatment, interacts synergistically with x rays to produce greatly enhanced aberration yields. The present experiments explore the effects of aphidicolin in human lymphocytes in the post-DNA-synthetic G/sub 2/ phase of the cell cycle. These experiments utilized labeling with tritiated thymidine to positively identify cells in the S phase at the time of treatment, and used serial colcemid collections and fixations to determine aberration yields over as much of the G/sub 2/ phase as feasible. Because DNA polymerase ..cap alpha.. is the only DNA synthetic or repair enzyme known to be affected by aphidicolin, we infer that this enzyme is directly involved in the repair of DNA lesions which can result in visible chromosomal aberrations. (DT)

  3. Oncogenic action of beta, proton, alpha and electron radiation on the rat skin

    International Nuclear Information System (INIS)

    Burns, F.J.

    1980-01-01

    Rat skin is being utilized as an empirical model for testing dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light, and polycyclic aromatic hydrocarbons. Molecular lesions in the skin DNA, including, strand breaks and thymine dimers, are being measured and compared to tumor induction. The induction and repair kinetics of molcular lesions are being compared to split dose repair. Modifiers and radiosensitizers are being utilized to test specific aspects of a chromosome breakage theory of radiation oncogenesis

  4. Alterations in alpha-adrenergic and muscarinic cholinergic receptor binding in rat brain following nonionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Gandhi, V.C.; Ross, D.H.

    1987-01-01

    Microwave radiation produces hyperthermia. The mammalian thermoregulatory system defends against changes in temperature by mobilizing diverse control mechanisms. Neurotransmitters play a major role in eliciting thermoregulatory responses. The involvement of adrenergic and muscarinic cholinergic receptors was investigated in radiation-induced hyperthermia. Rats were subjected to radiation at 700 MHz frequency and 15 mW/cm/sup 2/ power density and the body temperature was raised by 2.5 degrees C. Of six brain regions investigated only the hypothalamus showed significant changes in receptor states, confirming its pivotal role in thermoregulation. Adrenergic receptors, studied by (/sup 3/H)clonidine binding, showed a 36% decrease in binding following radiation after a 2.5 degrees C increase in body temperature, suggesting a mechanism to facilitate norepinephrine release. Norepinephrine may be speculated to maintain thermal homeostasis by activating heat dissipation. Muscarinic cholinergic receptors, studied by (3H)quinuclidinyl benzilate binding, showed a 65% increase in binding at the onset of radiation. This may be attributed to the release of acetylcholine in the hypothalamus in response to heat cumulation. The continued elevated binding during the period of cooling after radiation was shut off may suggest the existence of an extra-hypothalamic heat-loss pathway.

  5. Mechanism and computational model for Lyman-{alpha}-radiation generation by high-intensity-laser four-wave mixing in Kr-Ar gas

    Energy Technology Data Exchange (ETDEWEB)

    Louchev, Oleg A.; Saito, Norihito; Wada, Satoshi [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Bakule, Pavel [STFC, ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX (United Kingdom); Yokoyama, Koji [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Ishida, Katsuhiko; Iwasaki, Masahiko [Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan)

    2011-09-15

    We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-{alpha} (Ly-{alpha}) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-{alpha} generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-{alpha} radiation generation can achieve a value of {approx}5x10{sup -4} which is restricted by the total combined absorption of the fundamental and generated radiation.

  6. Aqueous polystyrene-fluor nanosuspensions for quantifying {alpha} and {beta}{sup -} radiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Donghua; Jay, Michael [Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536-0082 (United States)

    2007-06-06

    Fluor-containing nanoparticle suspensions prepared from styrene-in-water microemulsions were used to quantify {sup 14}C in various sample matrices by aqueous liquid scintillation counting. These suspensions exhibited greater quench resistance than a conventional organic cocktail and were very efficient at detecting higher energy {beta}{sup -} emitters and {alpha} emitters. A polymerizable scintillant was prepared to prevent leaching of fluors. The relationship between particle size, kinetic energy of {beta}{sup -} particles and counting efficiency was simulated by a theoretical model.

  7. Thiamin, riboflavin, and alpha-tocopherol content of exotic meats and loss due to gamma radiation.

    Science.gov (United States)

    Lakritz, L; Fox, J B; Thayer, D W

    1998-12-01

    Changes in thiamin, riboflavin, and alpha-tocopherol concentrations due to gamma irradiation were followed in alligator, caiman, bison, and ostrich (exotic) meats. The proximate composition showed that the exotic meats generally had lower fat content than domestic animal meats and that the thiamin content of the reptiles was lower. The changes in the vitamins due to irradiation were similar to those previously observed for domestic species. The results indicate that the loss of vitamins in these species is negligible insofar as the American diet is concerned, and that the concept of "chemiclearance" is applicable to exotic meats.

  8. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

    International Nuclear Information System (INIS)

    Kulkarni, A.; Bak, M. S.; Ha, S.; Joshirao, P.; Manchanda, V.; Kim, T.

    2015-01-01

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO 3 ) 4 ⋅ 5H 2 O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories

  9. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

    Science.gov (United States)

    Kulkarni, A.; Ha, S.; Joshirao, P.; Manchanda, V.; Bak, M. S.; Kim, T.

    2015-06-01

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO3)4 ṡ 5H2O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

  10. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

    Energy Technology Data Exchange (ETDEWEB)

    Kulkarni, A.; Bak, M. S., E-mail: tkim@skku.edu, E-mail: moonsoo@skku.edu [School of Mechanical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Ha, S. [SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Joshirao, P.; Manchanda, V. [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, T., E-mail: tkim@skku.edu, E-mail: moonsoo@skku.edu [School of Mechanical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2015-06-15

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO{sub 3}){sub 4} ⋅ 5H{sub 2}O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

  11. Influence of some exo nucleases in response to the induced genetic damage in Escherichia coli by alpha radiation

    International Nuclear Information System (INIS)

    Aguilar M, M.

    2005-01-01

    Within the strategies with those that E. coli counts to overcome to the genetic damage there is the SOS response, a group of genes that participate in repair and/or tolerance that it confers to the bacteria major opportunities of surviving. These genes are repressed and its only are expressed when it happens genetic damage. So that this system is activated it is necessary that DNA of a band exists and in this sense the double ruptures (RDB) its are not able to induce this response unless there is a previous processing. In stumps with defects in certain genes that have to do with repair of RDB (as recO, recJ and xonA) the activity of SOS is smaller than in a wild stump what suggests that these participate in the previous processes to the activation of the response. The ionizing radiation produce among other many lesions, RDB in greater or smaller proportion, depending on the ionization capacity. A parameter to evaluate this capacity is the lineal energy transfer (LET), defined as the average energy given by unit of distance travelled. In general the LET of the corpuscular radiations is a lot but high that of the electromagnetic one, for what produces bigger quantity of ionizations inside a restricted zone and it increases by this way the probability that RDB has been generated. This work has for object to infer the participation of xonA and recJ in this response and to evaluate the damage produced by ionizing radiation of different LET (alpha particles of different energies) in a stump with all the functional repair mechanisms. Its were considered two parameters: the survival and the activity of SOS evaluated by means of the chromo test. The results indicate that the activity of these exo nucleases is necessary for the repair of RDB as well as for the processing of lesions foresaw to the activation of SOS. As for the treatment with alphas of different energies is observed that so much the survival like the activity of SOS vary as the LET of the radiation changes

  12. Influence of the gamma radiation on the Schulz-Blaschke constant value; Influencia da radiacao gama no valor da constante de Schulz-Blaschke

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Erik Goncalves Holder da; Araujo, Elmo [Pernambuco Univ., Recife, PE (Brazil). Dept. de Energia Nuclear

    2002-07-01

    When conventional polymeric systems are exposed to the radiation, they undergo several effects on their molecular structure as the cross-linking and main chain scissions. In this work, we used the viscometer method because of its simplicity and efficiency on evaluation of those effects. In general, changes on molecular structure may largely affect the physical properties of polymers. By data obtained from this method, we can calculate the intrinsic viscosity, [{eta}], with direct application of Schulz-Blaschke equation: [{eta}]={eta}{sub red}/(1+k{sub sb},{eta}{sub esp}) , and to obtain the average viscosity molar mass, M{sub v}, through Mark-Houwink relation: [{eta}]=K(M{sub v}){sup a}. An important parameter to calculate [{eta}] is the Schulz-Blaschke constant, k{sub sb}, that depends on the polymer-solvent-temperature system. In this paper, it is studied the changes on k{sub sb} constant value of polymer system after exposition to the gamma irradiation. The polymers poly (methyl methacrylate), polystyrene and polycarbonate were chosen and irradiated in doses of 30 and 50 kGy. These polymers are often used on confection of medical supplies sterilized by ionizing irradiation. The results obtained before and after the exposition to the radiation showed large changes on k{sub sb} values of these materials. (author)

  13. High-energy gamma-quanta escape in the reaction of radiation capture of alpha-particles by sup 7 Li nucleus

    CERN Document Server

    Zhusupov, M A

    2002-01-01

    The reactions of radiation capture of alpha-particles by sup 7 Li nucleus which leads to excitation of the resonance levels of sup 1 sup 1 B nucleus were studied. The total cross sections of outlet high-energy gamma quanta were calculated. (author)

  14. Study of threshold energy registration of alpha particles on lexan nuclear track detector (passive) by Kr F laser pre-radiation

    International Nuclear Information System (INIS)

    Parvin, P.; Jaleh, B.; Hashemi, M. M.; Katoozi, M.; Amiri Rad, N.; Zamanipour, Z.; Zarea, A.

    2002-01-01

    The effect of Kr F laser pre-radiation has been investigated on both alpha track density and threshold energy of track registration. While no significant difference was observed on track density an nevertheless ∼100 keV shift of threshold energy occurred due to UV superficial hardening of Lexan detector

  15. The effects of radiation (beta/gamma and alpha) on cemented intermediate level waste

    International Nuclear Information System (INIS)

    Jones, D.V.C.; Wilding, C.R.

    1990-02-01

    A worldwide review of what has been published on the effects of radiation on cemented ILW has been carried out where properties such as composition and volume of any gas evolved/absorbed, physical properties, chemical evolution and dose rate were considered. It is clear that only a superficial knowledge of the underlying reasons for radiolytic effects exist although there is sufficient data to enable quantities of gas a function of storage time to be predicted. If long term predictions of behaviour are to be made then the understanding of basic radiation chemistry of cement grout needs to be developed in parallel with the wider study of understanding the effects at the elevated temperatures expected to be present in a repository. (author)

  16. Tumorigenic action of beta, proton, alpha and electron radiation on the rat skin

    Energy Technology Data Exchange (ETDEWEB)

    Burns, F.J.

    1980-01-01

    Rat skin is utilized as a model system for studying dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light and polycyclic aromatic hydrocarbons. Molecular lesions in the DNA of the epidermis, including strand breaks and thymine dimers, are measured and compared to the temporal and dose related aspects of tumor induction. The induction and repair kinetics of molecular lesions are compared to split dose recovery as modified by sensitizers and type of radition of oncogenic damage.

  17. Influence of the xonA gene of Escherichia coli in response to radiation; Influencia del gen xonA de Escherichia coli en la respuesta a radiacion

    Energy Technology Data Exchange (ETDEWEB)

    Ponce M, J.; Serment G, J.; Brena V, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    The Escherichia coli bacteria has a repair and tolerance system known as SOS that works when there is damage in the DNA. However it is necessary that this damage modifies before the system is activated. For this it has intended to the enzymes that degrade DNA like responsible for generating this modifications. It has already been identified to the product of the gene recJ and according to the results that here are presented that of the gene xonA has similar activity. When both genes fail, not alone the activity SOS is inhibited but rather the mortality increases, for ionizing radiation. The above mentioned reinforces the importance of these genes in the recovery to the damage caused to the genome. (Author)

  18. Properties and Gamma Radiation Stability of Immobilized Alpha Amylase on Synthetic and Natural Polymer Blends

    International Nuclear Information System (INIS)

    Ismaill, S.A.; Mobasher, E.F.; Shousha, M.A.

    2009-01-01

    αAmylase was immobilized onto two different copolymers. One of them was chitosan/alginate copolymer. The other copolymer was N- isopropyl acrylamide and alginate. αAmylase was immobilized by entrapment method. The optimum temperature and thermal inactivation of the free enzyme and the immobilized one were investigated. The activity of the immobilized enzyme was stable at higher temperature. Immobilized enzyme was stable under different ph. The immobilized enzymes showed a slight decrease in the relative activity after being used 12 times. Storage of the free and immobilized enzymes for 2 months showed that the free αamylase lost most of its catalytic activity after storage at this period. The storage of the immobilized enzyme in dry state was much better than that in the wet state. Storage at room temperature showed much less stability of the immobilized enzyme than in 4 degree C. Exposure the free and immobilized enzymes to gamma- radiation at doses (0-50 kGy) showed complete loss in activity of free enzyme at 5 kGy, while the immobilized enzyme showed high resistance to gamma- radiation. The kinetic studies of free and immobilized enzymes showed that the immobilization process increased Km and decreased V m ax values of the enzyme

  19. Properties and Gamma Radiation Stability of Immobilized Alpha Amylase on Synthetic and Natural Polymer Blends

    International Nuclear Information System (INIS)

    Ismaill, S.A.; Mobasher, E.F.; Shousha, M.A.

    2008-01-01

    αAmylase was immobilized onto two different copolymers. One of them was chitosan/alginate copolymer. The other copolymer was N- isopropyl acrylamide and alginate. αAmylase was immobilized by entrapment method. The optimum temperature and thermal inactivation of the free enzyme and the immobilized one were investigated. The activity of the immobilized enzyme was stable at higher temperature. Immobilized enzyme was stable under different ph. The immobilized enzymes showed a slight decrease in the relative activity after being used 12 times. Storage of the free and immobilized enzymes for 2 months showed that the free αamylase lost most of its catalytic activity after storage at this period. The storage of the immobilized enzyme in dry state was much better than that in the wet state. Storage at room temperature showed much less stability of the immobilized enzyme than in 4 degree C. Exposure the free and immobilized enzymes to gamma- radiation at doses (0-50 kGy) showed complete loss in activity of free enzyme at 5 kGy, while the immobilized enzyme showed high resistance to gamma- radiation. The kinetic studies of free and immobilized enzymes showed that the immobilization process increased Km and decreased V m ax values of the enzyme

  20. Real-time, automated characterization of surfaces for alpha and beta radiation

    International Nuclear Information System (INIS)

    Egidi, P.V.

    1997-01-01

    A new data collection system, called ABACUS trademark, has been developed that automates and expedites the collection, conversion, and reporting of radiological survey data of surfaces. Field testing of the system by Oak Ridge National Laboratory/Environmental Technology Section is currently underway. Preliminary results are presented. The system detects, discriminates, and separately displays the results for alpha and beta contamination scans on floors and walls with a single pass. Fixed-position static counting is also possible for quantitative measuring. The system is currently configured with five 100 cm 2 dual-phosphor plastic scintillation detectors mounted in a lightweight aluminum fixture that holds the detectors in a fixed array. ABACUS trademark can be configured with other detectors if desired. Ratemeter/scalars traditionally coupled to individual detectors have been replaced by a single unit that houses the power supply and discriminator circuit boards to support up to five detectors. The system is designed to be used by a single operator. Each detector's position and data are transmitted once per second and recorded on a nearby laptop computer. The data are converted to appropriate units, color-coded, and mapped to display graphically the findings for each detector in real-time. Reports can be generated immediately following the survey. Survey data can be exported in a variety of formats. Benefits of ABACUS trademark are: (1) immediate feedback to decision makers using the observational approach to characterization or remediation, (2) thorough documentation of survey results, (3) increased statistical confidence in scans by recording counts every second, (4) reduced paperwork and elimination of transcription errors, and (5) time and cost savings for collection, conversion, mapping, evaluating, and reporting data over traditional methods

  1. Low-dose radiation pretreatment improves survival of human ceiling culture-derived proliferative adipocytes (ccdPAs) under hypoxia via HIF-1 alpha and MMP-2 induction

    International Nuclear Information System (INIS)

    Adachi, Naoki; Kubota, Yoshitaka; Kosaka, Kentarou; Akita, Shinsuke; Sasahara, Yoshitarou; Kira, Tomoe; Kuroda, Masayuki; Mitsukawa, Nobuyuki; Bujo, Hideaki; Satoh, Kaneshige

    2015-01-01

    Poor survival is a major problem of adipocyte transplantation. We previously reported that VEGF and MMPs secreted from transplanted adipocytes are essential for angiogenesis and adipogenesis. Pretreatment with low-dose (5 Gy) radiation (LDR) increased VEGF, MMP-2, and HIF-1 alpha mRNA expression in human ceiling culture-derived proliferative adipocytes (hccdPAs). Gene expression after LDR differed between adipose-derived stem cells (hASCs) and hccdPAs. Pretreatment with LDR improved the survival of hccdPAs under hypoxia, which is inevitable in the early stages after transplantation. Upregulation of VEGF and MMP-2 after LDR in hccdPAs is mediated by HIF-1 alpha expression. Our results suggest that pretreatment with LDR may improve adipocyte graft survival in a clinical setting through upregulation of VEGF and MMP-2 via HIF-1 alpha. - Highlights: • Ceiling culture-derived proliferative adipocytes (ccdPAs) react to radiation. • Low-dose radiation (LDR) pretreatment improves survival of ccdPAs under hypoxia. • Gene expression after LDR differs between ccdPAs and adipose-derived stem cells. • LDR-induced increase in MMP-2 and VEGF is dependent on HIF-1 alpha induction. • LDR pretreatment may improve the adipocyte graft survival rate in clinical settings

  2. Low-dose radiation pretreatment improves survival of human ceiling culture-derived proliferative adipocytes (ccdPAs) under hypoxia via HIF-1 alpha and MMP-2 induction

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Naoki [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kubota, Yoshitaka, E-mail: kubota-cbu@umin.ac.jp [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kosaka, Kentarou; Akita, Shinsuke; Sasahara, Yoshitarou; Kira, Tomoe [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kuroda, Masayuki [Center for Advanced Medicine, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Mitsukawa, Nobuyuki [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Bujo, Hideaki [Department of Clinical-Laboratory and Experimental-Research Medicine, Toho University, Sakura Medical Center, 564-1 Shimoshizu, Sakura-shi, Chiba, #285-8741 (Japan); Satoh, Kaneshige [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan)

    2015-08-07

    Poor survival is a major problem of adipocyte transplantation. We previously reported that VEGF and MMPs secreted from transplanted adipocytes are essential for angiogenesis and adipogenesis. Pretreatment with low-dose (5 Gy) radiation (LDR) increased VEGF, MMP-2, and HIF-1 alpha mRNA expression in human ceiling culture-derived proliferative adipocytes (hccdPAs). Gene expression after LDR differed between adipose-derived stem cells (hASCs) and hccdPAs. Pretreatment with LDR improved the survival of hccdPAs under hypoxia, which is inevitable in the early stages after transplantation. Upregulation of VEGF and MMP-2 after LDR in hccdPAs is mediated by HIF-1 alpha expression. Our results suggest that pretreatment with LDR may improve adipocyte graft survival in a clinical setting through upregulation of VEGF and MMP-2 via HIF-1 alpha. - Highlights: • Ceiling culture-derived proliferative adipocytes (ccdPAs) react to radiation. • Low-dose radiation (LDR) pretreatment improves survival of ccdPAs under hypoxia. • Gene expression after LDR differs between ccdPAs and adipose-derived stem cells. • LDR-induced increase in MMP-2 and VEGF is dependent on HIF-1 alpha induction. • LDR pretreatment may improve the adipocyte graft survival rate in clinical settings.

  3. Effects of Trehalose on Thermodynamic Properties of Alpha-synuclein Revealed through Synchrotron Radiation Circular Dichroism

    Directory of Open Access Journals (Sweden)

    Paolo Ruzza

    2015-05-01

    Full Text Available Many neurodegenerative diseases, including Huntington’s, Alzheimer’s and Parkinson’s diseases, are characterized by protein misfolding and aggregation. The capability of trehalose to interfere with protein misfolding and aggregation has been recently evaluated by several research groups. In the present work, we studied, by means of synchrotron radiation circular dichroism (SRCD spectroscopy, the dose-effect of trehalose on α-synuclein conformation and/or stability to probe the capability of this osmolyte to interfere with α-synuclein’s aggregation. Our study indicated that a low trehalose concentration stabilized α-synuclein folding much better than at high concentration by blocking in vitro α-synuclein’s polymerisation. These results suggested that trehalose could be associated with other drugs leading to a new approach for treating Parkinson’s and other brain-related diseases.

  4. Experimental toxicology of alpha-emitters and human radiation safety results and prospects

    Energy Technology Data Exchange (ETDEWEB)

    Lyubchansky, Edward R.; Romanov, Sergey A. [Southern Ural Biophysics Institute, Ozyorsk (Russian Federation)

    2002-07-01

    Development of nuclear industry, disposition programs for fissile materials and irradiated nuclear fuel require improvement of radiation safety standards based on the refinement of biokinetic and radiobiological parameters accepted by ICRP. Results of studies in cohorts of exposed population (Japan, Russia) and workers (Russia) can be an important source of information in the future. Results of experimental efforts carried out earlier in different countries could be another valuable source. Large-scale studies in the field of radiotoxicology of plutonium, {sup 235} U, {sup 237} Np, {sup 241} Am on rodents, dogs, pigs were performed in Southern Ural Biophysics Institute; parameters for resorbtion, distribution and clearance of radionuclides depending on physical-chemical and biological factors were determined in the field of biokinetics; the clinical picture of acute, subacute and chronic exposure due to radionuclides was studied in the field of radiobiology. Dose-depending intake to the lung in mammals triggers the development of radiation pneumonitis and pulmonary fibrosis of different degrees of severity. Malignant tumors of critical organs at different ways of intake were revealed. The incidence of these tumors depend on the cumulative dose. The incidence of carcinomas in the lung in the field of optimal-blastomogenic doses also depend on the rate of non-uniformity of radionuclides distribution. Knowledge on experimental radiotoxicology acquired in SUBI witness that the revealed differences in parameter can be accounted, can be reduced to biological constants and used for purposes of standardization and protection of human. Joining of efforts of different countries in the mentioned direction is promising. Main results on metabolism and biological effect due to {sup 235} U, plutonium, {sup 237} Np and {sup 241} Am as well as some principles of experimental data extrapolation from animals to human will be presented here.

  5. Field methods for determining contents of alpha-radiating nuclides on the areas contaminated with depositions after the Chernobyl nuclear power station failure

    International Nuclear Information System (INIS)

    Pitkevich, V.A.; Duba, V.V.

    1992-01-01

    The work is aimed at creating field methods for estimating contents of alpha-radiating nuclides on the areas contaminated with depositions after the Chernobyl' station failure and for measuring the density of alpha-particles flux at various depths of soil. The methods make it possible to estimate the character of migration of isotopes Pu in depth. Instrumental and physical grounding of the methods are given. One can find the results of field measurements of α-active nuclides content in depositions. The results of measurement prove theoretical and practical feasibility of the suggested methods. 2 refs.; 4 figs.; 1 tabs

  6. Effect of polarized radiative transfer on the Hanle magnetic field determination in prominences: Analysis of hydrogen H alpha line observations at Pic-du-Midi

    Science.gov (United States)

    Bommier, V.; Deglinnocenti, E. L.; Leroy, J. L.; Sahal-Brechot, S.

    1985-01-01

    The linear polarization of the Hydrogen H alpha line of prominences has been computed, taking into account the effect of a magnetic field (Hanle effect), of the radiative transfer in the prominence, and of the depolarization due to collisions with the surrounding electrons and protons. The corresponding formalisms are developed in a forthcoming series of papers. In this paper, the main features of the computation method are summarized. The results of computation have been used for interpretation in terms of magnetic field vector measurements from H alpha polarimetric observations in prominences performed at Pic-du-Midi coronagraph-polarimeter. Simultaneous observations in one optically thin line (He I D(3)) and one optically thick line (H alpha) give an opportunity for solving the ambiguity on the field vector determination.

  7. Reoxygenation of human coronary smooth muscle cells suppresses HIF-1{alpha} gene expression and augments radiation-induced growth delay and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Grumann, T.; Arab, A.; Bode, C.; Hehrlein, C. [Dept. of Cardiology, Univ. Clinic of Freiburg (Germany); Guttenberger, R. [Dept. of Radiotherapy, Univ. Clinic of Freiburg (Germany)

    2006-01-01

    Background and Purpose: Catheter-based coronary brachytherapy with {beta}- and {gamma}-radiation is an evidence-based method to prevent restenosis after percutaneous transluminal coronary angioplasty (PTCA) and stent implantation, but the outcome may be PTCA are hypoxic. A lack of oxygen decreases the effect of low LET (linear energy transfer) irradiation. The authors assumed that reoxygenation of hypoxic human coronary smooth muscle cells (HCSMCs) improves the results of coronary brachytherapy. The expression of hypoxia-inducible factor 1{alpha} (HIF-1{alpha}) gene, and the rates of growth and apoptosis of hypoxic and reoxygenated HCSMCs after {gamma}-iradiation were therefore analyzed. Material and Methods: An in vitro model of megacolonies of HCSMCs was developed. After exposure to chronic hypoxia the HCSMCs were irradiated with graded doses of 2, 4, 8, and 16 Gy using a {sup 60}Co source either under hypoxia (pO{sub 2}<3 mmHg) or after reoxygenation (pO{sub 2}{approx}150 mmHg). RT-PCR (reverse transcription-polymerase chain reaction) analysis was used to quantify HIF-1{alpha} gene expression and the growth of HCSMC megacolonies was measured serially. The oxygen enhancement ratio (OER) was calculate from the specific growth delay. Apoptosis of HCSMCs was quantified by counting cells with specific DNA strand breaks using the TUNEL assy. Results: HIF-1{alpha} gene expression was markedly suppressed in reoxygenated cells versus hypoxic cells 30 min after {gamma}-irradiation at all radiation doses (158{+-}46% vs. 1,675{+-}1,211%; p<0.01). Apoptosis was markedly increased in reoxygenated HCSMCs. The OER was 1.8(95% CI[confidence interval]1.3-2.4). Therefore, reoxygenated HCSMCs require 44% less radiation dose to achieve the equivalent biological radiation effect compared to hypoxic HCSMCs. Conclusion: Reoxygenation of coronary smooth muscle cells should be considered an option to increase efficacy of coronary brachytherapy. This could be used to reduce radiation dose

  8. Calculus of radiolytic products generation in water due to alpha radiation. Determination of the spent nuclear fuels matrix alteration rate Determination of velocity of spent fuel matrix

    International Nuclear Information System (INIS)

    Quinones, J.; Serrano, J.; Diaz Arocas, P.; Rodriguez Almazan, J. L.; Bruno, J.; Cera, E.; Merino, J.; Esteban, J. A.; Martinez-Esparza, A.

    2000-01-01

    The generation of radiolytic products as a result of alpha radiation in the surface of the spent fuel is a key process in order to understand how the it becomes degraded in repository conditions. The present work has established a radiolytic model based on a set of reactions involving fuel oxidation-dissolution and radiolytic products recombination. It also includes the decrease of the dose rates as the main alpha emitters decay away. Four cases, with varying parameters of the system, have been assessed. The results show a decrease in both the concentration of the radiolytic products in the gap water and the degradation of the fuel matrix. It has been estimated that in the period of the evaluation (10''6 years) up to 52% of the pellet is altered in the conservative cases, whereas only 11% is altered in the realistic cases. No significant differences were observed when the carbonates reactions were included in the system. (Author)

  9. Phase 2 Randomized Controlled Trial of Radiation Therapy Plus Concurrent Interferon-Alpha and Retinoic Acid Versus Cisplatin for Stage III Cervical Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Partha, E-mail: BasuP@iarc.fr [Screening Group, Early Detection and Prevention Section, International Agency for Research on Cancer, Lyon (France); Jenson, Alfred Bennett [James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky (United States); Majhi, Tapas; Choudhury, Prabir [Department of Radiation Oncology, Chittaranjan National Cancer Institute, Kolkata (India); Mandal, Ranajit; Banerjee, Dipanwita [Department of Gynecological Oncology, Chittaranjan National Cancer Institute, Kolkata (India); Biswas, Jaydip [Department of Surgical Oncology, Chittaranjan National Cancer Institute, Kolkata (India); Pan, Jianmin; Rai, Shesh Nath; Ghim, Shin je; Miller, Donald [James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky (United States)

    2016-01-01

    Purpose: Because a combination of retinoic acid, interferon-alpha, and radiation therapy demonstrated synergistic action and effectiveness to treat advanced cervical cancers in earlier studies, we designed this randomized phase 2 open-label trial to assess efficacy and safety of interferon alpha-2b (IFN) and 13-cis-retinoic acid (RA) administered concomitantly with radiation therapy (IFN-RA-radiation) to treat stage III cervical cancer. Methods and Materials: Stage III cervical cancer patients were randomized to study and control groups in a 1:1 ratio. All patients were treated with radiation therapy; study arm patients received IFN (3 × 10{sup 6} IU subcutaneously) 3 times a week for 4 weeks and daily RA (40 mg orally) for 30 days starting on day 1 of radiation, whereas control arm patients received weekly cisplatinum (40 mg/m{sup 2}) for 5 weeks during radiation. Patients were followed for 3 years. The primary endpoint was overall survival at 3 years. Results: Patients in the study (n=104) and control (n=105) groups were comparable for clinicopathological characteristics, radiation therapy–related variables and treatment response. Proportions of disease-free patients in the study and control groups were 38.5% and 44.8%, respectively, after median follow-up of 29.2 months. Hazard ratios were 0.67 (95% confidence interval [CI]: 0.44-1.01) and 0.69 (95% CI: 0.44-1.06) for overall and disease-fee survival, respectively, comparing the study group to control, and demonstrated an inferior outcome with RA-IFN-radiation, although differences were statistically nonsignificant. Kaplan-Meier curves of disease-free and overall survival probabilities also showed inferior survival in the study group compared to those in the control. Acute toxicities of chemoradiation were significantly higher with 2 acute toxicity-related deaths. Conclusions: Treatment with RA-IFN-radiation did not demonstrate survival advantage over chemoradiation despite being less toxic. The

  10. X-radiation /E greater than 10 keV/, H-alpha and microwave emission during the impulsive phase of solar flares.

    Science.gov (United States)

    Vorpahl, J. A.

    1972-01-01

    A study has been made of the variation in hard (E greater than 10 keV) X-radiation, H-alpha and microwave emission during the impulsive phase of solar flares. Analysis shows that the rise-time in the 20-30-keV X-ray spike depends on the electron hardness. The impulsive phase is also marked by an abrupt, very intense increase in H-alpha emission in one or more knots of the flare. Properties of these H-alpha kernels include: (1) a luminosity several times greater than the surrounding flare, (2) an intensity rise starting about 20-30 sec before, peaking about 20-25 sec after, and lasting about twice as long as the hard spike, (3) a location lower in the chromosphere than the remaining flare, (4) essentially no expansion prior to the hard spike, and (5) a position within 6000 km of the boundary separating polarities, usually forming on both sides of the neutral line near both feet of the same tube of force. Correspondingly, impulsive microwave events are characterized by: (1) great similarity in burst structure with 20-32 keV X-rays but only above 5000 MHz, (2) typical low frequency burst cutoff between 1400-3800 MHz, and (3) maximum emission above 7500 MHz.

  11. Evaluation of internal alpha radiation exposure and subsequent infertility among a cohort of women formerly employed in the radium dial industry.

    Energy Technology Data Exchange (ETDEWEB)

    Schieve, L. A.; Davis, F.; Roeske, J.; Handler, A.; Freels, S.; Stinchcomb, T.; Keane, A.; Environmental Research; Univ. of Illinois at Chicago; Univ. of Chicago; DePaul Univ.

    1997-02-01

    This study examined the effect of internal exposure to {alpha}-particle radiation on subsequent fertility among women employed in the radium dial industry prior to 1930, when appreciable amounts of radium were often ingested through the practice of pointing the paint brush with the lips. The analysis was limited to women for whom a radium body burden measurement had been obtained and who were married prior to age 45 (n=603). Internal radiation dose to the ovary was calculated based on initial intakes of radium-226 and radium-228, average ovarian mass, number and energy of {alpha} particles emitted, fraction of energy absorbed with in the ovary, effective retention integrals and estimated photon irradiation. Time between marriage and pregnancy, number of pregnancies and number of live births served as surrogates for fertility. Radiation appeared to have no effect on fertility at estimated cumulative ovarian dose equivalents below 5 Sv; above this dose, however, statistically significant declines in both number of pregnancies and live births were observed. These trends persisted after multivariable adjustment for potential confounding variables and after exclusion of subjects contributing a potential classification or selection bias to the study. Additionally, the high-dose group experienced fewer live births than would have been expected based on population rates. There were no differences in time to first pregnancy between high- and low-dose groups. These results are consistent with earlier studies of {gamma}-ray exposures and suggest that exposure to high doses of radiation from internally deposited radium reduces fertility rather than inducing sterility.

  12. Effects of infrared radiation, solar cooking and microwave cooking on alpha-amylase inhibitor in sorghum (Sorghum bicolor L.).

    Science.gov (United States)

    Mulimani, V H; Supriya, D

    1994-10-01

    Three domestic cooking methods were studied in alpha-amylase inhibitory activity in sorghum grains. In all the treatments, overnight soaked seeds lost amylase inhibitory activity much faster. All the three treatments reduced the inhibitory activity. Use of solar cooker for reducing amylase inhibitory activity works out very economically and efficiently. Microwave cooking eliminates amylase inhibitory activity within 5 minutes.

  13. Immunization with radiation-attenuated Plasmodium berghei sporozoites induces liver cCD8alpha+DC that activate CD8+T cells against liver-stage malaria.

    Directory of Open Access Journals (Sweden)

    Ousman Jobe

    Full Text Available Immunization with radiation (gamma-attenuated Plasmodia sporozoites (gamma-spz confers sterile and long-lasting immunity against malaria liver-stage infection. In the P. berghei gamma-spz model, protection is linked to liver CD8+ T cells that express an effector/memory (T(EM phenotype, (CD44(hiCD45RB(loCD62L(lo, and produce IFN-gamma. However, neither the antigen presenting cells (APC that activate these CD8+ T(EM cells nor the site of their induction have been fully investigated. Because conventional (cCD8alpha+ DC (a subset of CD11c+ DC are considered the major inducers of CD8+ T cells, in this study we focused primarily on cCD8alpha+ DC from livers of mice immunized with Pb gamma-spz and asked whether the cCD8alpha+ DC might be involved in the activation of CD8+ T(EM cells. We demonstrate that multiple exposures of mice to Pb gamma-spz lead to a progressive and nearly concurrent accumulation in the liver but not the spleen of both the CD11c+NK1.1(- DC and CD8+ T(EM cells. Upon adoptive transfer, liver CD11c+NK1.1(- DC from Pb gamma-spz-immunized mice induced protective immunity against sporozoite challenge. Moreover, in an in vitro system, liver cCD8alpha(+ DC induced naïve CD8+ T cells to express the CD8+ T(EM phenotype and to secrete IFN-gamma. The in vitro induction of functional CD8+ T(EM cells by cCD8alpha+ DC was inhibited by anti-MHC class I and anti-IL-12 mAbs. These data suggest that liver cCD8alpha+ DC present liver-stage antigens to activate CD8+ T(EM cells, the pre-eminent effectors against pre-erythrocytic malaria. These results provide important implications towards a design of anti-malaria vaccines.

  14. Impact of alpha-, gamma-, and delta-tocopherol on the radiation induced oxidation of rapeseed oil triacylglycerols

    Energy Technology Data Exchange (ETDEWEB)

    Braunrath, Robert; Isnardy, Bettina; Solar, Sonja, E-mail: sonja.solar@univie.ac.at; Elmadfa, Ibrahim

    2010-07-15

    Gamma-irradiation (doses: 2, 4, 7, and 10 kGy) was used as oxidation tool to study the antioxidant effects of alpha-, gamma-, and delta-tocopherol (enrichments 500-5000 ppm) in purified rapeseed oil triacylglycerols (RSOTG). Fatty acid composition, tocopherol degradation, primary (conjugated dienes (CD) and peroxide value (POV)) and secondary (p-anisidine value) oxidation products were chosen as test parameters. Fatty acid composition did not change. While secondary oxidation products could not be found in the irradiated samples, the POVs and CDs showed a significant, dose-dependent increase. alpha-Tocopherol did not inhibit the formation of peroxides, whereas gamma- and delta-tocopherol reduced the POVs by more than 30%. No uniform effect of the different tocopherol concentrations at the particular doses could be established. The influence of the individual tocopherols on the CD formation was not pronounced. The degradation of the tocopherols decreased with increasing concentration. None of the tocopherols showed a prooxidant effect.

  15. Development of U-235 and U-238 analysis by electrodeposition technique using alpha spectrometer as radiation counter

    International Nuclear Information System (INIS)

    Suwanporung, U.

    1984-01-01

    An analytical method for U-235 and U-238 in uranium sample by electrodeposition technique followed by alpha spectrometry was developed. The process involved purification of uranium by anion exchange resin, Amberlite IR A-400 prior to electrodeposition of uranium on stainless steel disc and counted the alpha activity by using a silicon surface barrier detector. The alpha energies could be resolved clearly. The quantity of uranium isotopes could be calculated by comparing with that of the uranium standard which was treated by the same method. The optimum current density for the electrodeposition was found to be 170 m A/cm 2 and electrodeposition time was about 3 hours. A depleted uranium sample was analyzed by this method and found that uranium-234, uranium-235 and uranium-238 contents were 0.0026%, 0.25% and 99.74% respectively. The studies covered also the effect of temperature on electrodeposition of uranium and the effects of impurities in the sample: arsenic, iron, molybdenum and vanadium on the accuracy of analyses

  16. Alpha alumina exoemissive and thermoluminescent properties. Application to the dosimetry of ionizing radiations in case of accident

    International Nuclear Information System (INIS)

    Alessandri, M.F.

    1989-06-01

    This work consists of two parts. In the first part, a phenomenon of phototransfer in Thermostimulated Exoelectronic Emission (T.S.E.E.) is pointed out. Study of intrinsic T.S.E.E. of alpha alumina exposed to ultraviolet (U.V.) excitation of energy superior to 4 eV shows three T.S.E.E. peaks situated at 240, 325, 535 0 C (heating rate of 2 0 C.s -1 ). The phototransfer phenomenon is then characterized notably by the lowering of the U.V. excitation threshold to 3.5 eV and the increasing of T.S.E.E. response for U.V. energies between 3.5 and 6 eV. Discussion and interpretation of the results obtained are based on the perfect analogy with the phototransfer of Thermoluminescence (T.L.) observed on a similar type of alpha alumina. The second part describes the application of alpha alumina dosimetric properties to accidental irradiation dosimetry and cartography. The material is bound to a textile support to be used for clothes manufacturing for irradiation risking workers. T.S.E.E. and T.L. properties of the selected fabric have been studied. - T.S.E.E. response to a beta irradiation of strontium 90 covers the region [0.01 - 10 Gy], with a dispersion of ± 20%, a non significant thermic fading beyond 72 hours after irradiation and a very important optical fading; - the region in T.L. extends from 0.25 to 10 Gy with X irradiation (45 kV) and from 0.5 to 10 Gy with gamma irradiation of cobalt 60 and caesium 137; the dispersion is ± 20%, the thermic fading is weak and the optical fading is negligible in artificial light or does not vary any more after 5 days of sunlight exposition [fr

  17. Regulation of ionizing radiation-induced adhesion of breast cancer cells to fibronectin by alpha5beta1 integrin.

    Science.gov (United States)

    Lee, Shin Hee; Cheng, Huiwen; Yuan, Ye; Wu, Shiyong

    2014-06-01

    Ionizing radiation (IR) is commonly used for cancer therapy, however, its potential influence on cancer metastatic potential remains controversial. In this study, we elucidated the role of integrins in regulation of IR-altered adhesion between breast cancer cells and extracellular matrix (ECM) proteins, which is a key step in the initial phase of metastasis. Our data suggest that the extent of effect that ionizing radiation had on cell adhesion depended on the genetic background of the breast cancer cells. Ionizing radiation was a better adhesion inducer for p53-mutated cells, such as MDA-MB-231 cells, than for p53 wild-type cells, such as MCF-7 cells. While IR-induced adhesions between MDA-MB-231 cells to fibronectin, laminin, collagen I and collagen IV, only blocking of the adhesion between α5β1 integrin and fibronectin using anti-α5β1 integrin antibody could completely inhibit the radiation-induced adhesion of the cells. A soluble Arg-Gly-Asp peptide, the binding motif for fibronectin binding integrins, could also reduce the adhesion of the cells to fibronectin with or without ionizing radiation exposure. The inhibition of the cell-fibronectin interaction also affected, but did not always correlate with, transwell migration of the cancer cells. In addition, our data showed that the total expression of α5 integrin and surface expression of α5β1 integrin were increased in the cells treated with ionizing radiation. The increased surface expression of α5β1 integrin, along with the adhesion between the cells and fibronectin, could be inhibited by both ataxia telangiectasia mutated (ATM) and Rad3-related (ATR) kinase inhibitors. These results suggested that ATM/ATR-mediated surface expression of α5β1 integrin might play a central role in regulation of ionizing radiation-altered adhesion.

  18. Hot electron refluxing in the short intense laser pulse interactions with solid targets and its influence on K-alpha radiation

    Czech Academy of Sciences Publication Activity Database

    Horný, Vojtěch; Klimo, O.

    2015-01-01

    Roč. 60, č. 2 (2015), s. 233-237 ISSN 0029-5922. [Kudowa Summer School 2014 "Towards Fusion Energy"/12./. Kudowa Zdrój, 09.06.2014-13.06.2014] R&D Projects: GA MŠk LM2010014 Grant - others:GA MŠk(CZ) LM2010005 Institutional support: RVO:61389021 Keywords : electron recirculation * electron refl uxing * K- alpha radiation * laser–plasma interactions * particle--in-cell simulation Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 0.546, year: 2015 http://www.nukleonika.pl/www/back/full/vol60_2015/v60n2p233f.pdf

  19. Biodistribution and radiation dosimetry of the {alpha}{sub 7} nicotinic acetylcholine receptor ligand [{sup 11}C]CHIBA-1001 in humans

    Energy Technology Data Exchange (ETDEWEB)

    Sakata, Muneyuki [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1 Naka-cho, Itabashi-ku, Tokyo 173-0022 (Japan); Wu, Jin; Toyohara, Jun [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1 Naka-cho, Itabashi-ku, Tokyo 173-0022 (Japan); Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670 (Japan); Oda, Keiichi [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1 Naka-cho, Itabashi-ku, Tokyo 173-0022 (Japan); Ishikawa, Masatomo [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1 Naka-cho, Itabashi-ku, Tokyo 173-0022 (Japan); Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670 (Japan); Ishii, Kenji [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1 Naka-cho, Itabashi-ku, Tokyo 173-0022 (Japan); Hashimoto, Kenji [Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670 (Japan); Ishiwata, Kiichi, E-mail: ishiwata@pet.tmig.or.j [Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1 Naka-cho, Itabashi-ku, Tokyo 173-0022 (Japan)

    2011-04-15

    Introduction: 4-[{sup 11}C]Methylphenyl 2,4-diazabicyclo[3.2.2]nonane-2-carboxylate ([{sup 11}C]CHIBA-1001) is a newly developed positron emission tomography (PET) ligand for mapping {alpha}{sub 7} nicotinic acetylcholine receptors. We investigated whole-body biodistribution and radiation dosimetry of [{sup 11}C]CHIBA-1001 in humans and compared the results with those obtained in mice. Methods: Dynamic whole-body PET was carried out for three human subjects after administering a bolus injection of [{sup 11}C]CHIBA-1001. Emission scans were collected in two-dimensional mode over five bed positions. Regions of interest were placed over 12 organs. Radiation dosimetry was estimated from the residence times of these source organs using the OLINDA program. Biodistribution data from mice were also used for the prediction of radiation dosimetry in humans, and results with and those without accommodation of different proportions of organ-to-total-body mass were compared with the results from the human PET study. Results: In humans, the highest accumulation was observed in the liver, whereas in mice, the highest accumulation was observed in the urinary bladder. The estimated effective dose from the human PET study was 6.9 {mu}Sv/MBq, and that from mice was much underestimated. Conclusion: Effective dose estimates for [{sup 11}C]CHIBA-1001 were compatible with those associated with other common nuclear medicine tests. Absorption doses among several organs were considerably different between the human and mouse studies. Human dosimetry studies for the investigation of radiation safety are desirable as one of the first clinical trials of new PET probes before their application in subsequent clinical investigations.

  20. Fast approximate radiative transfer method for visualizing the fine structure of prominences in the hydrogen H alpha line

    Czech Academy of Sciences Publication Activity Database

    Heinzel, Petr; Gunár, S.; Anzer, U.

    2015-01-01

    Roč. 579, July (2015), A16/1-A16/6 ISSN 0004-6361 R&D Projects: GA ČR GAP209/12/0906 EU Projects: European Commission(XE) 328138 Institutional support: RVO:67985815 Keywords : radiative transfer * Sun * filaments Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.378, year: 2014

  1. Molecular stress response in the CNS of mice after systemic exposureto interferon-alpha, ionizing radiation and ketamine

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, Xiu R.; Marchetti, Francesco; Lu, Xiaochen; Wyrobek, Andrew J.

    2009-03-03

    We previously showed that the expression of troponin T1 (Tnnt 1) was induced in the central nervous system (CNS) of adultmice 30 min after treatment with ketamine, a glutamate N-methyl-D-aspartic acid (NMDA) receptor antagonist. We hypothesized that Tnnt 1 expression may be an early molecular biomarker of stress response in the CNS of mice. To further evaluate this hypothesis, we investigated the regional expression of Tnnt 1 in the mouse brain using RNA in situ hybridization 4 h after systemic exposure to interferon-a (IFN-a) and gamma ionizing radiation, both of which have be associated with wide ranges of neuropsychiatric complications. Adult B6C3F1 male mice were treated with either human IFN-a (a single i.p. injection at 1 x 105 IU/kg) or whole body gamma-radiation (10 cGy or 2 Gy). Patterns of Tnnt 1 transcript expression were compared in various CNS regions after IFN-a, radiation and ketamine treatments (previous study). Tnnt 1 expression was consistently induced in pyramidal neurons of cerebral cortex and hippocampus after all treatment regimens including 10 cGy of ionizing radiation. Regional expression of Tnnt 1 was induced in Purkinje cells of cerebellum after ionizing radiation and ketamine treatment; but not after IFN-a treatment. None of the three treatments induced Tnnt 1 expression in glial cells. The patterns of Tnnt 1 expression in pyramidal neurons of cerebral cortex andhippocampus, which are both known to play important roles in cognitive function, memory and emotion, suggest that the expression of Tnnt 1 may be an early molecular biomarker of induced CNS stress.

  2. SM22{alpha}-induced activation of p16{sup INK4a}/retinoblastoma pathway promotes cellular senescence caused by a subclinical dose of {gamma}-radiation and doxorubicin in HepG2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Rim; Lee, Hee Min; Lee, So Yong; Kim, Eun Jin; Kim, Kug Chan [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Paik, Sang Gi [Department of Biology, School of Biosciences and Biotechnology, Chungnam National University, Daejeon (Korea, Republic of); Cho, Eun Wie, E-mail: ewcho@kribb.re.kr [Daejeon-KRIBB-FHCRC Cooperation Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Kim, In Gyu, E-mail: igkim@kaeri.re.kr [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-09-10

    Research highlights: {yields} SM22{alpha} overexpression in HepG2 cells leads cells to a growth arrest state, and the treatment of a subclinical dose of {gamma}-radiation or doxorubicin promotes cellular senescence. {yields} SM22{alpha} overexpression elevates p16{sup INK4a} followed by pRB activation, but there are no effects on p53/p21{sup WAF1/Cip1} pathway. {yields} SM22{alpha}-induced MT-1G activates p16{sup INK4a}/pRB pathway, which promotes cellular senescence by damaging agents. -- Abstract: Smooth muscle protein 22-alpha (SM22{alpha}) is known as a transformation- and shape change-sensitive actin cross-linking protein found in smooth muscle tissue and fibroblasts; however, its functional role remains uncertain. We reported previously that SM22{alpha} overexpression confers resistance against anti-cancer drugs or radiation via induction of metallothionein (MT) isozymes in HepG2 cells. In this study, we demonstrate that SM22{alpha} overexpression leads cells to a growth arrest state and promotes cellular senescence caused by treatment with a subclinical dose of {gamma}-radiation (0.05 and 0.1 Gy) or doxorubicin (0.01 and 0.05 {mu}g/ml), compared to control cells. Senescence growth arrest is known to be controlled by p53 phosphorylation/p21{sup WAF1/Cip1} induction or p16{sup INK4a}/retinoblastoma protein (pRB) activation. SM22{alpha} overexpression in HepG2 cells elevated p16{sup INK4a} followed by pRB activation, but did not activate the p53/p21{sup WAF1/Cip1} pathway. Moreover, MT-1G, which is induced by SM22{alpha} overexpression, was involved in the activation of the p16{sup INK4a}/pRB pathway, which led to a growth arrest state and promoted cellular senescence caused by damaging agents. Our findings provide the first demonstration that SM22{alpha} modulates cellular senescence caused by damaging agents via regulation of the p16{sup INK4a}/pRB pathway in HepG2 cells and that these effects of SM22{alpha} are partially mediated by MT-1G.

  3. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  4. Study on the immobilization of alpha-amylase by radiation-induced polymerization at low-temperature, (1)

    International Nuclear Information System (INIS)

    Yoshida, Masaru; Kumakura, Minoru; Kaetsu, Isao

    1975-07-01

    The immobilization of enzymes by radiation-induced polymerization at low temperatures has been studied. It is important to know how the enzymes are affected by irradiation. The radiation effect of enzyme itself before immobilization must thus be investigated. In radiation effect on α-amylase from Bacillus subtilis, interesting results were obtained, as follows. The enzyme is very stable for irradiation in the total dose range of 1 x 10 4 to 1 x 10 7 R, and the activity is hardly affected. And further, the relative activity increases by irradiation, when the α-amylase is of high purity or contains some appropriate additive. A certain substance such as diatomaceous earth or CaCl 2 thus decreases the activity, while the addition of DRIERITE composed mainly of CaSO 4 increases the activity. α-Amylase is then more stable and higher in activity in the irradiation at lower temperatures. The activity is independent of presence or absence of the ambient air. In conclusion, α-amylase is very stable for irradiation at low temperatures; therefore, its immobilization by polymerization at low temperature is recommended. (auth.)

  5. ¿Efecto o influencia televisiva?

    Directory of Open Access Journals (Sweden)

    Marcia de la Flor Arbulú

    1986-06-01

    Full Text Available Deslindar los conceptos de Efecto e Influencia en el impacto de la observación de T.V., y adscribir cada término a las áreas de investigación sobre el tema, así como a un Modelo de Comunicación, es el objetivo del presente artículo.

  6. Los mecanismos de influencia en el liderazgo

    OpenAIRE

    Arango Cardona, Patricia

    2016-01-01

    Este trabajo tiene como objetivo fundamental identificar las tácticas de influencia que utiliza el señor Carlos Pérez, gerente y socio principal de G. & M., en su trato cotidiano con sus colaboradores, así como la reacción de estos últimos ante dichas tácticas.

  7. Influence of temperature in TL signal induced by gamma radiation in zircon prepared by sol gel via; Influencia de la temperatura en la senal TL inducida por la radiacion gamma en zirconia preparada via solgel

    Energy Technology Data Exchange (ETDEWEB)

    Salas, P.; Castano, V.M. [Instituto de Fisica, UNAM, Laboratorio Juriquilla, A.P. 1-1010, 76001 Queretaro (Mexico); Mendoza A, D.; Gonzalez M, P.R. [ININ, Mexico, D.F. (Mexico); Rosa C, E. de la [Centro de Investigaciones en Optical, Leon, Gto. (Mexico)

    2000-07-01

    In this work, it was realized a study of the temperature effects in thermoluminescent signal (Tl) induced by gamma radiation in zircon, which was prepared by the sol gel method. According to the obtained results, the zircon thermically treated at 500 C or over is sensitive to radiation. This sensitivity is increased when the temperature in study is augmented, moreover, the Tl spectra form also is modified with the temperature increment. The samples thermically treated at 750 C or over present a linear response in the dose interval 27 to 165 Gy; therefore, such materials result promissories for dosimetric purposes. (Author)

  8. Evaluation gamma radiation in composite sisal fiber- polyurethane derived of castor oil by bending test; Avaliacao da influencia da radiacao gama em compositos de fibra de sisal - poliuretano derivado de oleo de mamona atraves de ensaios de flexao

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Felipe H. de; Geraldo, Ricardo R.; Vasco, Marina C.; Azevedo, Elaine, E-mail: helunica@yahoo.com.br [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Claro Neto, Salvador [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Instituto de Quimica

    2015-07-01

    Materials used for making furniture and accessories or positioning in X -ray examination rooms should not exhale volatile organic compounds and are resistant to ionizing radiation. One solution is the use of vegetable fiber and polyurethane composites of vegetable origin, since they are biodegradable, derived from renewable raw materials and have no volatile organic compounds. The main difficulty in developing this material is fiber adhesion with the polymer. The objective of this study is to evaluate the mechanical properties of composite sisal fiber composite, without further treatment, and polyurethane derived from castor oil, with a dose of 25 kGy gamma radiation, subjected to 3 points bending tests. (author)

  9. Influence of gamma radiation on the levels of polyphenols and lethality of ethanol extracts of Anacardium occidentale Linn., against Biomphalaria glabrata; Influencia da radiacao gama na acao moluscicida de extratos de cajueiro em Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Santos, G.H.F.; Silva, E.B., E-mail: santosghf@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear. Grupo de Radioprotecao e Radioecologia; Melo, A.M.M.A.; Lima, C.S.A [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica; Amorim, E.L.C.; Peixoto Sobrinho, T.J.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Farmacia

    2013-08-15

    Plant materials rich in phenolic compounds, such as Anacardium occidentale Linn., Have been used as alternatives to synthetic pesticides in Biomphalaria glabrata control programs, intermediate host of Schistosoma mansoni. Studies show that ionizing radiation can influence the content of phenolic compounds and thus their biological actions. The aim of this study was to evaluate the influence of gamma radiation of {sup 60}Co in polyphenol composition of hydroalcoholic extracts of bark and leaves of A. occidentale and evaluate the toxicity of these extracts to embryos and adults of B. glabrata. To achieve this goal this, the extracts were irradiated at 10 kGy, the controls being maintained from 0 kGy and positive (CaCO{sub 3}) and negative (H{sub 2}O). We quantified the total phenols by the Folin-Ciocalteau and tannins by precipitation of casein. Extracts were used at a concentration of 100 mg/L. The results showed that the radiation caused the changes to the leaves, the percentage of polyphenols and tannins, and the percentage of lethality in embryos and adults Biomphalaria glabrata, these percentages being: 13 ± 5 (0 kGy) and 27 ± 2.5 (10 kGy), and 36.67 ± 5.77 (0 kGy), and 56.67 ± 5.77 (10 kGy), respectively. Gamma radiation caused significant changes in the levels of polyphenols in the extracts of leaves of Anacardium ocidentale Linn., translated by the increased toxicity of this extract against embryos and adults of Biomphalaria glabrata. This indicates that gamma radiation can be used as an agent potentiating the toxicity of plant extracts on the alternate use of these materials as molluscicides. (author)

  10. Induction of NKG2D ligands by gamma radiation and tumor necrosis factor-alpha may participate in the tissue damage during acute graft-versus-host disease.

    Science.gov (United States)

    Gannagé, Monique; Buzyn, Agnès; Bogiatzi, Sofia I; Lambert, Marion; Soumelis, Vassili; Dal Cortivo, Liliane; Cavazzana-Calvo, Marina; Brousse, Nicole; Caillat-Zucman, Sophie

    2008-03-27

    Immunopathology of acute graft-versus-host disease (aGVHD) involves secretion of proinflammatory cytokines with subsequent expression of danger signals by injured host tissues. This explanation, however, does not explain the cluster of aGVHD target organs (skin, gut, and liver). NKG2D ligands (MICA/B and ULBP1-3 proteins) are stress-induced molecules that act as danger signals to alert NK and alphabeta or gammadelta CD8 T cells through engagement of the activating NKG2D receptor. We observed a strong and reversible induction of MICA/B expression in skin and liver sections during aGVHD. Tumor necrosis factor-alpha and gamma-radiation up-regulated expression of MICA/B and ULBP proteins in vitro on skin and intestine epithelial cell lines and ex vivo in normal skin explants. This NKG2D-ligand induction was regulated by a complex interplay between NFkB and JNK activation pathways. Our data suggest that NKG2D ligand induction might participate in the amplification loop that leads to tissue damage during aGVHD.

  11. The relationship between internally deposited alpha-particle radiation and subsite-specific liver cancer and liver cirrhosis. An analysis of published data

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, G.B. [Radiation Effects Research Foundation, Hiroshima (Japan)

    2002-12-01

    Chronic exposure to high linear energy transfer (LET) radiation has been shown to cause liver cancer in humans based on studies of patients who received Thorotrast, a colloidal suspension of thorium dioxide formerly used as a radiological contrast agent, and on studies of Russian nuclear weapons workers exposed to internally ingested plutonium. Risk estimates for these exposures and specific subtypes of liver cancer have not been previously reported. Combining published data with tumor registry data pertinent to the Thorotrast cohorts in Germany, Denmark, Portugal, and Japan and to Russian workers, we generally found significantly elevated risks of three major histologic types of liver tumors: hepatocellular carcinoma (HCC), cholangiocarcinoma (CC), and hemangiosarcoma (HS) for Thorotrast exposures. In contrast, HS was the only liver tumor significantly associated with the lower {alpha}-particle doses experienced by the Russian workers. Excess cases per 1,000 persons exposed to Thorotrast were similar for the three liver cancer subtypes but lower for plutonium exposure. Odds ratios (OR) of HS and CC for Thorotrast were from 26 to 789 and from 1 to 31 times higher than those for HCC, respectively. ORs of liver cirrhosis for Thorotrast exposure ranged from 2.7 (95% confidence interval (CI): 2.2-3.4) to 6.7 (5.1-8.7). (author)

  12. {sup 213}Bi-DOTATOC receptor-targeted alpha-radionuclide therapy induces remission in neuroendocrine tumours refractory to beta radiation: a first-in-human experience

    Energy Technology Data Exchange (ETDEWEB)

    Kratochwil, C.; Giesel, F.L.; Mier, W.; Haberkorn, U. [University Hospital Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany); Bruchertseifer, F.; Apostolidis, C.; Morgenstern, A. [European Commission, Institute for Transuranium Elements, Karlsruhe (Germany); Boll, R.; Murphy, K. [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    2014-11-15

    Radiopeptide therapy using a somatostatin analogue labelled with a beta emitter such as {sup 90}Y/{sup 177}Lu-DOTATOC is a new therapeutic option in neuroendocrine cancer. Alternative treatments for patients with refractory disease are rare. Here we report the first-in-human experience with {sup 213}Bi-DOTATOC targeted alpha therapy (TAT) in patients pretreated with beta emitters. Seven patients with progressive advanced neuroendocrine liver metastases refractory to treatment with {sup 90}Y/{sup 177}Lu-DOTATOC were treated with an intraarterial infusion of {sup 213}Bi-DOTATOC, and one patient with bone marrow carcinosis was treated with a systemic infusion of {sup 213}Bi-DOTATOC. Haematological, kidney and endocrine toxicities were assessed according to CTCAE criteria. Radiological response was assessed with contrast-enhanced MRI and {sup 68}Ga-DOTATOC-PET/CT. More than 2 years of follow-up were available in seven patients. The biodistribution of {sup 213}Bi-DOTATOC was evaluable with 440 keV gamma emission scans, and demonstrated specific tumour binding. Enduring responses were observed in all treated patients. Chronic kidney toxicity was moderate. Acute haematotoxicity was even less pronounced than with the preceding beta therapies. TAT can induce remission of tumours refractory to beta radiation with favourable acute and mid-term toxicity at therapeutic effective doses. (orig.)

  13. 213Bi-DOTATOC receptor-targeted alpha-radionuclide therapy induces remission in neuroendocrine tumours refractory to beta radiation: a first-in-human experience

    International Nuclear Information System (INIS)

    Kratochwil, C.; Giesel, F.L.; Mier, W.; Haberkorn, U.; Bruchertseifer, F.; Apostolidis, C.; Morgenstern, A.; Boll, R.; Murphy, K.

    2014-01-01

    Radiopeptide therapy using a somatostatin analogue labelled with a beta emitter such as 90 Y/ 177 Lu-DOTATOC is a new therapeutic option in neuroendocrine cancer. Alternative treatments for patients with refractory disease are rare. Here we report the first-in-human experience with 213 Bi-DOTATOC targeted alpha therapy (TAT) in patients pretreated with beta emitters. Seven patients with progressive advanced neuroendocrine liver metastases refractory to treatment with 90 Y/ 177 Lu-DOTATOC were treated with an intraarterial infusion of 213 Bi-DOTATOC, and one patient with bone marrow carcinosis was treated with a systemic infusion of 213 Bi-DOTATOC. Haematological, kidney and endocrine toxicities were assessed according to CTCAE criteria. Radiological response was assessed with contrast-enhanced MRI and 68 Ga-DOTATOC-PET/CT. More than 2 years of follow-up were available in seven patients. The biodistribution of 213 Bi-DOTATOC was evaluable with 440 keV gamma emission scans, and demonstrated specific tumour binding. Enduring responses were observed in all treated patients. Chronic kidney toxicity was moderate. Acute haematotoxicity was even less pronounced than with the preceding beta therapies. TAT can induce remission of tumours refractory to beta radiation with favourable acute and mid-term toxicity at therapeutic effective doses. (orig.)

  14. Influence of the main reactive species formed during the detoxication process of toxins by ionizing radiation; Influencia das principais especies reativas formadas durante o processo de destoxicacao de toxinas por radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Murilo Casare da

    2003-07-01

    Ionizing radiation has been satisfactorily employed for venoms detoxification. In this report, the radiation was employed to verify the effects caused by the radiolysis products of water on two toxins (Crotoxin and Crotamine) purified from Crotalus durissus terrificus venom. These effects were analyzed using some substances called 'scavengers', those substances competes for specific reactive species hindering them to act on the toxins molecules. In order to study the possible structural damages caused on the toxins, UV spectra, fluorescence, mass spectrometry, enzymatic activity were employed. In addition, biochemical techniques were employed to evaluate the decrease of toxicity and the immunogenicity of toxins before and after the irradiation. Our results indicate that the irradiation promotes structural damages, even at low doses. These modifications lead to a gradual decrease in toxicity, however, the immunogenic properties of the toxins are preserved. (author)

  15. Advanced gastric adenocarcinoma. Influence of preoperative radiation therapy on toxicity and long-term survival rates; Adenocarcinoma gastrico avancado. Analise da toxicidade e da influencia da radioterapia pre-operatoria nos indices de sobrevivencia a longo prazo

    Energy Technology Data Exchange (ETDEWEB)

    Malzoni, Carlos Eduardo

    1996-12-31

    The surgical treatment of gastric cancer has better long-term survival rates when performed in patients with early gastric cancer. Worse results are obtained in treatment of advanced gastric cancer. Most patients in west centers are treated in advanced stages. A great number of them go through a surgical treatment unable by itself to cure them. the frequent local recurrence caused by failure of the surgical treatment has been keeping poor survival rates in patients with advanced gastric cancer for decades. The desire of improving survival is the reason of the use of adjuvant therapies. This paper achieved the retrospective study of the influence of preoperative radiation therapy (2000 cGy) in long-term survival rates (120 months) of patients with advanced gastric cancer on stages IIIa, IIIb and IV. The possible injuries caused in the liver and kidney were observed also as well as first group was treated by surgical and radiation therapies and the second received surgical treatment only. There was no statistical difference between the two groups when sex, age, race, occurrence of other diseases, nutritional assessment, TNM stage, occurrence of obstruction or bleeding caused by tumor, surgical procedure and hepatic and renal function were considered. Survival rates and changes on hepatic and renal function were statistically compared. The results showed a statistic improvement on the long-term survival rates of stage IIIa patients treated by preoperative radiation therapy. No statistic difference was observed on hepatic or renal function between the groups. No adverse influence of radiation therapy method was detected by the used parameters. There was no statistical difference between the two groups when immediate surgical complications were considered. (author) 112 refs., 34 tabs.

  16. Microstructural characteristics of the hydroxyapatite and its influence in the Tl signal induced by gamma radiation; Caracteristicas microestructurales de la hidroxiapatita y su influencia en la senal Tl inducida por la radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza A, D.; Gonzalez M, P.R.; Hernandez A, M. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Estrada G, R. [Depto. de Fisica y Matematicas, Universidad Iberoamericana, Santa Fe, 01000 Mexico D.F. (Mexico); Rodriguez L, V. [Centro Universitario de Vinculacion, BUAP, Puebla (Mexico)

    2003-07-01

    The analysis carried out on different materials has shown that the quantity and type of dopants play an important role in the behaviour thermoluminescent signal induced by the ionizing radiation. More recent studies have also shown that the grain size influences strongly in the thermoluminescent signal. Plus still, the crystal growth habit and the crystalline degree have an important effect in the type and intensity thermoluminescent signal. In this sense, we present this work on the analysis of the thermoluminescent signal induced by the gamma radiation in the hydroxyapatite ceramic. Depending the growth habit, a variation of the peak temperature location, signal intensity and linearity range was observed; in particular cases a lineal relationship between glow curve and radiation dose was in the range from 2 to 1000 Gray. These results are complemented with a microstructural and crystalline degree analysis through scanning electron microscopy and X-ray Diffraction. The dose-response over the whole irradiation range opening up the possibility of employing this bio material as a dosimeter. (Author)

  17. Gamma radiation effects of {sup 60} Co on Bombyx mori (Lep., Bombycidae) modifying the silk fiber production; Influencia da radiacao gama ({sup 60} Co) na producao de fios de seda em Bombyx mori(Lep.,Bombycidae)

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro Junior, Francisco [Universidade Metodista de Piracicaba (UNIMEP), SP (Brazil); Bendassolli, Jose A. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil)

    1997-12-01

    The present work aimed to verify the biological effects of the application of different doses of gamma radiation during the fifth instar of the silkworm catepillar. Sevently eight silkworm caterpillars (Bombyx mori) were irradiated with {gamma}{sup 60} Co radiation at the initial period of the fifth instar. The caterpillars were divided and classified in six batches of thirteen individuals each. Treatments 1 through 5 received 20, 40, 60, 80 and 100 Gy, respectively, and the control, also consisted of thirteen caterpillars, was not irradiated. The results showed a general increase in the silk fiber content in the irradiated batches compared to the control. The weight of the silk cocoons was higher with increasing doses of irradiation, from 20 to 80 Gy, respectively, followed by a decrease in weight in the treatment irradiated with 100 Gy. the results obtained in this experiment enable the conclusion that the radiation applied to the caterpillars significantly influenced the production of silk fiber in this species. (author). 4 refs., 2 figs., 3 tabs.

  18. Influence of gamma radiation on molluscicidal and antimicrobial action of leaf and stem bark of Ziziphus joazeiro; Influencia da radiacao gama sobre a acao moluscicida e antimicrobiana da folha e casca do caule de Ziziphus joazeiro

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, Fabricio O.; Siqueira, Williams N.; Lima, Maira V.; Melo, Larissa S.A.; Luna Filho, Ricardo L.C.; Morais, Vinicius H.T.; Oliveira, Maria L.M.; Melo, Ana M.M.A.; Silva, Edvane B., E-mail: fabriciomendesbio@gmail.com, E-mail: williams.wns@gmail.com, E-mail: mairavasconceloslima@gmail.com, E-mail: larissamelo.pe@gmail.com, E-mail: ricardolclf@hotmail.com, E-mail: viniciushtmorais@hotmail.com, E-mail: mluizamarinho@gmail.com, E-mail: amdemelo@hotmail.com, E-mail: s, E-mail: fabriciomendesbio@gmail.com, E-mail: williams.wns@gmail.com, E-mail: edvborges@yahoo.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2017-11-01

    Ionizing radiation is a physical agent used in several areas of knowledge: in medicine for the diagnosis and treatment of diseases, in the industry, it is apply in the generation of energy, sterilization of equipment and food, for example. Studies show that radiation can modify the molecular structure of substances of natural origin, potentiating or inactivating their function. The compounds derived from plants have received special attention because they constitute a form of medicinal therapy that has been growing notably in recent years. In addition, products of natural origin may also aid in the control of microbiological or animal vectors of parasites. Of the various species of plants being studied, Ziziphus joazeiro, popularly known as jua, native to the Caatinga, is commercially exploited for the manufacture of cosmetics and as anti-inflammatory, antimicrobial, anti influenza, fever and gastritis, bruises and has molluscicidal activity. Therefore, the objective of this work was to evaluate the influence of cobalt-60 gamma radiation on leaf and bark extracts of Z. joazeiro stem, evaluating possible changes in molluscicidal and antimicrobial action. For the experiments, the Z joazeiro extracts were irradiated with doses of 5, 7.5 and 10 kGy (Gammacell-Cobalt-60, dose rate 7.222 kGy/h). Adult mollusks (n = 60) and embryos (n = 1800) of Biomphalaria glabrata were distributed in the following groups: negative control 1 (water only); negative control 2 (extract only); positive control (CuCO{sub 3}); and three groups submitted to irradiated extracts. The antibacterial assay was performed with Gram-positive microorganisms (Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis, Enterococcus faecalis) belonging to the collection of the Departamento de Antibioticos of the UFPE by disc diffusion method. Statistical analysis was perform by Student's t-test and chi-square test, with a confidence interval of 95%. The results showed that the ionizing radiation

  19. Calculus of radiolytic products generation in water due to alpha radiation. Determination of the spent nuclear fuels matrix alteration rate Determination of velocity of spent fuel matrix; Calculo de la generacion de productos radioliticos en agua por radiacion {alpha}. Determinacion de la velocidad de alteracion de la matriz del combustible nuclear gastado

    Energy Technology Data Exchange (ETDEWEB)

    Quinones, J.; Serrano, J.; Diaz Arocas, P.; Rodriguez Almazan, J. L. [Ciemat. Madrid (Spain); Bruno, J.; Cera, E.; Merino, J.; Esteban, J. A.; Martinez-Esparza, A. [Enresa. Madrid (Spain)

    2000-07-01

    The generation of radiolytic products as a result of alpha radiation in the surface of the spent fuel is a key process in order to understand how the it becomes degraded in repository conditions. The present work has established a radiolytic model based on a set of reactions involving fuel oxidation-dissolution and radiolytic products recombination. It also includes the decrease of the dose rates as the main alpha emitters decay away. Four cases, with varying parameters of the system, have been assessed. The results show a decrease in both the concentration of the radiolytic products in the gap water and the degradation of the fuel matrix. It has been estimated that in the period of the evaluation (10''6 years) up to 52% of the pellet is altered in the conservative cases, whereas only 11% is altered in the realistic cases. No significant differences were observed when the carbonates reactions were included in the system. (Author)

  20. DIAGNOSTICO DE INFLUENCIA EN SISTEMAS ECONOMETRICOS COINTEGRADOS

    OpenAIRE

    TORRES TRUJILLO; MARCELO; TORRES TRUJILLO; MARCELO

    2011-01-01

    El presente trabajo desarrolla la técnica de diagnóstico de influencia local en modelos de corrección de errores (MCE) de sistemas econométricos cointegrados con el fin evaluar la sensibilidad de observaciones potencialmente influyentes sobre las estimaciones de verosimilitud máxima o inferencias hechas sobre el modelo: perturbando el parámetro de escala el cual conectamos con la técnica de diagnóstico de eliminación de casos y que nos permite evaluar analíticamente el supuesto de homoceda...

  1. Influencia de la Medicina Francesa en Colombia

    OpenAIRE

    Ernesto Andrade Valderrama

    1991-01-01

    Me da autoridad para hablar ante ustedes, quienes por segunda vez en nuestra Historia y ahora en una seria Asociación reviven los lazos de la Medicina Colombiana con la gran Escuela Francesa, el haber pertenecido a una de las últimas generaciones, formadas en la Universidad Nacional, que estudiaron toda la carrera en los textos provenientes de ese país y recibieron de maestros, casi todos formados bajo esa notable influencia, todos los principios y normas del ejercicio profesional. D...

  2. Buffett's Alpha

    DEFF Research Database (Denmark)

    Frazzini, Andrea; Kabiller, David; Heje Pedersen, Lasse

    Berkshire Hathaway has realized a Sharpe ratio of 0.76, higher than any other stock or mutual fund with a history of more than 30 years, and Berkshire has a significant alpha to traditional risk factors. However, we find that the alpha becomes insignificant when controlling for exposures to Betting-Against-Beta...... in publicly traded stocks versus wholly-owned private companies, we find that the former performs the best, suggesting that Buffett's returns are more due to stock selection than to his effect on management. These results have broad implications for market efficiency and the implementability of academic...

  3. Directional radiation detectors

    Science.gov (United States)

    Dowell, Jonathan L.

    2017-09-12

    Directional radiation detectors and systems, methods, and computer-readable media for using directional radiation detectors to locate a radiation source are provided herein. A directional radiation detector includes a radiation sensor. A radiation attenuator partially surrounds the radiation sensor and defines an aperture through which incident radiation is received by the radiation sensor. The aperture is positioned such that when incident radiation is received directly through the aperture and by the radiation sensor, a source of the incident radiation is located within a solid angle defined by the aperture. The radiation sensor senses at least one of alpha particles, beta particles, gamma particles, or neutrons.

  4. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  5. Relaciones intergubernamentales, actores emergentes y mecanismos de influencia

    OpenAIRE

    Obdulia Vega; Raul Pacheco

    2004-01-01

    Las ONG ejercen influencia sobre los gobiernos, misma que ha sido estudiada con poca sistematicidad. En este trabajo, se examina el elusivo concepto de influencia y se establece un recorte teórico y analítico para el estudio de la influencia de las ONG ambientalistas sobre las relaciones entre diferentes niveles de gobierno en México. Se analiza el caso de la construcción de un confinamiento de residuos peligrosos en Guadalcázar (cerca de la ciudad de San Luis Potosí). En dicho caso, las r...

  6. In vitro effects of infrared A radiation on the synthesis of MMP-1, catalase, superoxide dismutase and GADD45 alpha protein.

    Science.gov (United States)

    Costa, Adilson; Eberlin, Samara; Clerici, Stefano P; Abdalla, Beatrice M Z

    2015-01-01

    Harmful influences in the process of photoaging and skin damage are associated with infrared A (IRA) radiation, such as, disturbance of dermal extracellular matrix by up regulation of matrix metalloproteinase-1 (MMP1). Furthermore, DNA damage, induction of cytotoxicity and oxidative stress by decreasing natural antioxidant ability has been reported after acute exposure to IRA. The present study provides additional evidence that IRA radiation response in human skin fibroblasts produces deleterious effects to the cell, such as accelerating aging and weakening of their antioxidant defense mechanism. Human skin fibroblasts were exposed to a non-cytotoxic dose of IRA radiation and cultured for different periods for further collection of cell-free supernatants and lysates, and quantification of MMP-1, catalase, superoxide dismutase, and GADD45a. Our results corroborate previous published data and strongly indicate a negative impact of IRA radiation on the skin physiological by mechanisms involving reduced endogenous antioxidant enzymatic defense, increased MMP-1 and decreased repair process of DNA by reducing GADD45a protein, in cultured human fibroblasts. From a clinical perspective, IRA radiation acts by mechanisms distinct from those observed in ultraviolet radiation indicating the need for developing and making available cosmetics for skin care with properties beyond protection exerted by traditional sunscreens.

  7. Evaluation of granulated BGO, GSO:Ce, YAG:Ce, CaF2:Eu and ZnS:Ag for alpha/beta pulse shape discrimination in a flow-cell radiation detector

    International Nuclear Information System (INIS)

    DeVol, T.A.; Chotoo, S.B.; Fjeld, R.A.

    1999-01-01

    Granulated BGO, GSO:Ce, YAG:Ce, and CaF 2 :Eu; CaF 2 :Eu coated with a fluorescent polymer, and combinations of coated and uncoated CaF 2 :Eu with ZnS:Ag were evaluated for their ability to discriminate between alpha and beta particles in a flow-cell radiation detector. The evaluations were based on the analysis of pulse shape spectra. Various granulated scintillators were packed into flow cell detectors that were coils of 3.0 mm ODx1.5 mm ID fluorinated ethylene propylene Teflon[reg] tubing positioned between dual photomultiplier tubes for analysis. The best pulse shape discrimination was obtained for a combination of equal masses of uncoated CaF 2 :Eu (63-90 μm) and ZnS:Ag (10 μm), which had a 9% spillover. Additional research is needed to reduce the spillover

  8. Evaluation of granulated BGO, GSO:Ce, YAG:Ce, CaF sub 2 :Eu and ZnS:Ag for alpha/beta pulse shape discrimination in a flow-cell radiation detector

    CERN Document Server

    Devol, T A; Fjeld, R A

    1999-01-01

    Granulated BGO, GSO:Ce, YAG:Ce, and CaF sub 2 :Eu; CaF sub 2 :Eu coated with a fluorescent polymer, and combinations of coated and uncoated CaF sub 2 :Eu with ZnS:Ag were evaluated for their ability to discriminate between alpha and beta particles in a flow-cell radiation detector. The evaluations were based on the analysis of pulse shape spectra. Various granulated scintillators were packed into flow cell detectors that were coils of 3.0 mm ODx1.5 mm ID fluorinated ethylene propylene Teflon[reg] tubing positioned between dual photomultiplier tubes for analysis. The best pulse shape discrimination was obtained for a combination of equal masses of uncoated CaF sub 2 :Eu (63-90 mu m) and ZnS:Ag (10 mu m), which had a 9% spillover. Additional research is needed to reduce the spillover.

  9. Coulomb correction to elastic. alpha. -. alpha. scattering

    Energy Technology Data Exchange (ETDEWEB)

    Bera, P.K.; Jana, A.K.; Haque, N.; Talukdar, B. (Department of Physics, Visva-Bharati University, Santiniketan-731235, West Bengal, India (IN))

    1991-02-01

    The elastic {alpha}-{alpha} scattering is treated within the framework of a generalized phase-function method (GPFM). This generalization consists in absorbing the effect of Coulomb interaction in the comparison functions for developing the phase equation. Based on values of scattering phase shifts computed by the present method, it is concluded that the GPFM provides an uncomplicated approach to rigorous Coulomb correction in the {alpha}-{alpha} scattering.

  10. Localized External Beam Radiation Therapy (EBRT) to the Pelvis Induces Systemic IL-1Beta and TNF-Alpha Production: Role of the TNF-Alpha Signaling in EBRT-Induced Fatigue.

    Science.gov (United States)

    McDonald, Tasha L; Hung, Arthur Y; Thomas, Charles R; Wood, Lisa J

    2016-01-01

    Prostate cancer patients undergoing localized external beam radiation therapy (EBRT) can experience a progressive increase in fatigue, which can affect physical functioning and quality of life. The purpose of this study was to develop a mouse EBRT prostate cancer treatment model with which to determine the role of pro-inflammatory cytokines in the genesis of EBRT-related fatigue. We assessed voluntary wheel-running activity (VWRA) as a proxy for fatigue, food intake and body weight in male C57BL/6 mice undergoing EBRT to the pelvis. In the first experiment, anesthetized male C57BL/6 mice underwent fractionated EBRT to the pelvis for a total dose of 68.2 Gy, thereby mimicking a clinically relevant therapeutic dose and frequency. The day after the last treatment, levels of IL-1β and TNF-α in plasma along with mRNA levels in liver, colon and whole brain were measured. EBRT-induced fatigue resulted in reduced body weight, diminished food intake, and increased plasma and tissue levels of IL-1β and TNF-α. In a follow-up experiment, we used TNF-α-deficient mice to further delineate the role of TNF-α signaling in EBRT-induced sickness behavior. EBRT-induced changes in fatigue, food intake and body weight were no different between TNF-α deficient mice and their wild-type counterparts. Taken together our data demonstrate that a clinically relevant localized irradiation of the pelvis induces a systemic IL-1β and TNF-α response and sickness behavior in mice, but the TNF-α signaling pathway alone does not independently mediate these effects.

  11. Intrahepatic expression of interferon alpha & interferon alpha ...

    African Journals Online (AJOL)

    kemrilib

    Alpha m-RNA while 30% only expressed Interferon Alpha Receptor m-RNA. Responders and non-responders to Interferon therapy ... expression of IFN Alpha Receptor mRNA. Regardless of the response to interferon, histological .... generation reverse hybridisation, line probe assay. (Inno-LiPA HCV II; Innogenetics, Ghent,.

  12. Influencia de la identidad grupal en la cohesion estudio piloto

    OpenAIRE

    Bohórquez, M. Rocío; Lorenzo, Macarena

    2012-01-01

    La cohesión grupal es uno de los procesos dinámicos más estudiados en los equipos deportivos, su relación con procesos como el clima grupal o la eficacia colectiva ha sido ampliamente abordada. Sin embargo, el estudio de la influencia que la identidad grupal pudiera tener sobre la cohesión está aún por emprender. Así, el objetivo de este estudio fue determinar la influencia que la identidad grupal pudiera tener sobre la cohesión de los equipos deportivos. En el experimento p...

  13. Tumorigenic action of beta, proton, alpha, and electron radiation on the rat skin. Progress report, August 1, 1974--July 31, 1975

    International Nuclear Information System (INIS)

    Albert, R.E.; Burns, F.J.

    1975-01-01

    The carcinogenic effects of ionizing radiation (α, β, electron, and protons) on rat skin were studied in an attempt to learn more about radiation carcinogenesis, especially how various parameters of the irradiation, such as dose distribution within the tissue and dose rate, affect the yield of tumors. It was found that when the dose was localized to a small region of skin, the tumor yield was reduced and the magnitude of the reduction indicated that the region of reduced response might extend about 150 μ into the irradiated zone. The proliferative state of the hair follicles at the time of irradiation had relatively little effect on tumor induction although old animals were less susceptible than young or newborn animals. The penetration requirement of at least 0.3 mm for producing tumors suggests that the hair follicle germ cells could be the oncogenic targets. Comprehensive experiments to measure the rate of recovery for tumor induction in split-dose exposure protocols indicated a recovery halftime of about 4 hrs for electrons and significant recovery for protons, which was used in a model to predict how recovery should affect the tumor response at low dose rates. Combinations of ionizing radiation and ultraviolet light were applied to rat skin to determine whether they are additive for producing tumors. (U.S.)

  14. Suppression of transformed foci, induced by alpha radiation of C3H 10T1/2 cells, by untransformed cells

    International Nuclear Information System (INIS)

    Lloyd, E.L.; Gemmell, M.A.; Henning, C.B.

    1978-01-01

    The C3H 10T1/2 CL8 cell line obtained from a mouse embryo has been widely used for screening chemical carcinogens. Transformed foci are easily distinguishable in this system as crisscrossed, piled-up cells which stain more deeply than the surrounding untransformed cells. When these foci are ringcloned and subcultured, they have been shown to give rise to malignant tumors in C3H immunodepressed mice. Previous work showed that such malignant transformations, which occurred with a dose dependent frequency, could be induced by alpha particle irradiation. The present study, in turn, demonstrates that the expression of these transformations can be completely suppressed by co-cultivating the transformed cells with a large number of untransformed cells. The precise ratio of the number of untransformed cells to transformed cells to give complete suppression was found to vary in different experiments. Maximum effects were seen when a small number of transformed cells in low passage were used. These experiments may provide at least a partial explanation for the greatly increased frequency of transformations per cell irradiated in vitro, compared with the number of tumors observed after irradiation of the same number of cells in vivo. In addition, if conditions could be optimized whereby transformed foci could reproducibly be eliminated by the use of a known number of untransformed cells, this might have important applications in the prevention and treatment of certain human cancers

  15. Technology information profile: Long-Range Alpha Detector (LRAD)

    International Nuclear Information System (INIS)

    Bounds, J.A.

    1995-01-01

    The idea to develop some sort of radiation detection using this knowledge was passed down and after extensive and ground-breaking development, practical and sensitive devices were invented that are particularly sensitive to alpha radiation. Well over twenty different LRAD detectors have been successfully built and plans exist for many more. No parallel work is known to exist, and the ability to detect alpha radiation at such distances is unequaled

  16. Systemic Targeted Alpha Radiotherapy for Cancer

    Directory of Open Access Journals (Sweden)

    Allan B. J.

    2013-09-01

    Full Text Available Background: The fundamental principles of internal targeted alpha therapy for cancer were established many decades ago.The high linear energy transfer (LET of alpha radiation to the targeted cancer cellscauses double strand breaks in DNA. At the same time, the short range radiation spares adjacent normal tissues. This targeted approach complements conventional external beam radiotherapy and chemotherapy. Such therapies fail on several fronts, such as lack of control of some primary cancers (e.g.glioblastoma multiformeand to inhibit the development of lethal metastatic cancer after successful treatment of the primary cancer. Objective: This review charts the developing role of systemic high LET, internal radiation therapy. Method: Targeted alpha therapy is a rapidly advancing experimental therapy that holds promise to deliver high cytotoxicity to targeted cancer cells. Initially thought to be indicated for leukemia and micrometastases, there is now evidence that solid tumors can also be regressed. Results: Alpha therapy may be molecular or physiological in its targeting. Alpha emitting radioisotopes such as Bi-212, Bi-213, At-211 and Ac-225 are used to label monoclonal antibodies or proteins that target specifc cancer cells. Alternatively, Radium-233 is used for palliative therapy of breast and prostate cancers because of its bone seeking properties. Conclusion: Preclinical studies and clinical trials of alpha therapy are discussed for leukemia, lymphoma, melanoma, glioblastoma multiforme, bone metastases, ovarian cancer, pancreatic cancer and other cancers.

  17. Effects of alpha particles on zebrafish embryos

    International Nuclear Information System (INIS)

    Yum, E.H.W.; Choi, V.W.Y.; Yu, K.N.; Li, V.W.T.; Cheng, S.H.

    2008-01-01

    Full text: Ionizing radiation such as X-ray and alpha particles can damage cellular macromolecules, which can lead to DNA single- and double-strand breaks. In the present work, we studied the effects of alpha particles on dechorionated zebrafish embryos. Thin polyallyldiglycol carbonate (PADC) films with a thickness of 16 μm were prepared from commercially available PADC films (with thickness of 100 μm) by chemical etching and used as support substrates for holding zebrafish embryos for alpha-particle irradiation. These films recorded alpha-particle hit positions, quantified the number and energy of alpha particles actually incident on the embryo cells, and thus enabled the calculation of the dose absorbed by the embryo cells. Irradiation was made at 1.25 hours post fertilization (hpf) with various absorbed dose. TdT-mediated dUTP Nick-End Labeling (TUNEL) assay was performed on the embryos at different time stages after irradiation. Marked apoptosis was detected only in embryos at earlier time stages. The results showed that DNA double-strand break during zebrafish embryogenesis can be induced by alpha-particle irradiation, which suggests that zebrafish is a potential model for assessing the effects of alpha-particle radiation

  18. Radiation physics

    International Nuclear Information System (INIS)

    Nam, Sang Hui

    1991-02-01

    This book deals with radiation physics, which introduces atomic theory and an atomic nucleus of materials, conception of an atom and materials, wave and particle, X ray generation and character, a radioactive element and change law, nature of radioactivity, neutron rays, fission, alpha collapse and beta collage and a neutrino collapse of artificial radioactivity such as collapse of artificial nucleus and artificial radioactivity and radiative capture, interaction with materials like interaction between a charged particle and materials and interaction among X-ray, r-ray and materials, radiation of quantity and unit and a charged particle accelerator.

  19. Alpha particles detection in nitrocellulose

    International Nuclear Information System (INIS)

    Romero C, M.

    1976-01-01

    The method for the manufacturing of the detection films follows these steps: preparation of the mass which includes nitrocellulose in the form of cotton as raw material ethyl acetate, cellosolve acetate, isopropyl and butyl alcohols as solvents and dioctyl phtalate as plasticiser; dilution of the paste; pouring of the diluted mass; and drying of the detection films. The results obtained experimentally are: The determination of the development times of the different thicknesses of the manufactured films. Response linearity of the detectors, variation of the number of tracks according to the distance of the source to the detector. Sizes of the diameter of the tracks depending of the distance detector-alpha emmission source. As a conclusion we can say the the nitrocellulose detectors are specific for alpha radiation; the more effective thicknesses in uranium prospecting works were those of 60 microns, since for the laboratory works the thicknesses of 30 to 40 microns were the ideal; the development technique of the detection films is simple and cheap and can be realized even in another place than the laboratory; this way of the manufacturing of nitrocellulose detection film sensitive to alpha nuclear radiation is open to future research. (author)

  20. Influencia de la Medicina Francesa en Colombia

    Directory of Open Access Journals (Sweden)

    Ernesto Andrade Valderrama

    1991-12-01

    Full Text Available

    Me da autoridad para hablar ante ustedes, quienes por segunda vez en nuestra Historia y ahora en una seria Asociación reviven los lazos de la Medicina Colombiana con la gran Escuela Francesa, el haber pertenecido a una de las últimas generaciones, formadas en la Universidad Nacional, que estudiaron toda la carrera en los textos provenientes de ese país y recibieron de maestros, casi todos formados bajo esa notable influencia, todos los principios y normas del ejercicio profesional. Disminuída casi al mínimo, tras la ruptura de comunicación y situación originada por la Segunda Guerra Mundial y tras los cambios, que en el orden social y tecnológico han ocurrido en estos últimos cincuenta años, hoy buscan todas las entidades que tienen a su cargo la Educación Médica, revivir la imagen de un médico general, familiar o comunitario, que pueda restituir la perdida relación Médico-Paciente, base de la antigua Escuela Francesa y que correctamente orientado y utilizando la esplendorosa tecnología de este final de siglo, pueda ser la salvación para el cuidado integral del paciente del próximo milenio que se avecina.

    A través de la Historia, se ha visto cómo el cetro de la Medicina ha rotado por diversas culturas y países. España, por razones políticas, alejada de Francia, recibió, en el campo médico el influjo de Alemania e Inglaterra. A sus colonias de América, fué muy poco lo que de ellas llegó. Sólo hasta finales del siglo XVIII, vino un hombre genial, naturalista y médico, quien pasara a la Historia Universal con la célebre Expedición Botánica y que fué el padre de la medicina colombiana: José Celestino Mutis. El puso en marcha la primera Escuela de Medicina, en 1802 y allí estudiaron los primeros médicos que pasada la Guerra de la Independencia, encabezados por José Félix Merizalde, habrían de recibir la primera Misión Francesa, en 1823.

    Médicos franceses conocidos antes en el país fueron

  1. Las influencias orientales en el pensamiento occidental: de la ilustración al idealismo postkantiano

    OpenAIRE

    Terol, Gabriel

    2011-01-01

    Repasamos las influencias orientalistas del pensamiento occidental en el período comprendido entre los siglos XVII y XVIII, subrayando estas influencias en tres representantes de la Ilustración (Leibniz, Wolff y Hume), un representante de la reacción al racionalismo ilustrado (Herder) y dos representantes del idealismo poskantiano posterior (Schelling y Hegel), para constatar la relevancia de estas influencias. Proponemos exponer la trayectoria del pensamiento occidental de modo que alcancemo...

  2. Relaciones intergubernamentales, actores emergentes y mecanismos de influencia

    Directory of Open Access Journals (Sweden)

    Obdulia Vega

    2004-01-01

    Full Text Available Las ONG ejercen influencia sobre los gobiernos, misma que ha sido estudiada con poca sistematicidad. En este trabajo, se examina el elusivo concepto de influencia y se establece un recorte teórico y analítico para el estudio de la influencia de las ONG ambientalistas sobre las relaciones entre diferentes niveles de gobierno en México. Se analiza el caso de la construcción de un confinamiento de residuos peligrosos en Guadalcázar (cerca de la ciudad de San Luis Potosí. En dicho caso, las relaciones entre gobierno federal, gobierno estatal y gobierno municipal en México se vieron afectadas por la presión externa del gobierno de los Estados Unidos de Norteamérica. Más aún, la influencia de la sociedad civil potosina, a través de ONGA cuya esfera de atención se concentraba en el área geográfica de San Luis Potosí, ejerció un impacto decisivo sobre la forma en la cual se desarrollaron los eventos que culminaron en una disputa formal en los tribunales a la luz del Tratado de Libre Comercio de América del Norte (TLCAN En este trabajo examinamos el caso de Metalclad a la luz de un marco teórico interdisciplinario, y definimos hasta qué punto las ONGA lograron influir sobre las relaciones intergubernamentales entre gobiernos federal, estatal y municipal.

  3. About the reactions sup 3 H(alpha,gamma) sup 7 Li and sup 3 He(alpha,gamma) sup 7 Be

    CERN Document Server

    Loeffler, W

    1993-01-01

    In this article the current experimental and theoretical status of the radiative alpha capture reactions sup 3 H(alpha,gamma) sup 7 Li and sup 3 He(alpha,gamma) sup 7 Be and their relations to primordial nucleosynthesis and the solar neutrino problem are reviewed. (author)

  4. The determination of $\\alpha_s$ by the ALPHA collaboration

    CERN Document Server

    Bruno, Mattia

    2016-01-01

    We review the ALPHA collaboration strategy for obtaining the QCD coupling at high scale. In the three-flavor effective theory it avoids the use of perturbation theory at $\\alpha > 0.2$ and at the same time has the physical scales small compared to the cutoff $1/a$ in all stages of the computation. The result $\\Lambda_\\overline{MS}^{(3)}=332(14)$~MeV is translated to $\\alpha_\\overline{MS}(m_Z)=0.1179(10)(2)$ by use of (high order) perturbative relations between the effective theory couplings at the charm and beauty quark "thresholds". The error of this perturbative step is discussed and estimated as $0.0002$.

  5. Influence of the noble metals (Pd, Au, Ag) in the thermoluminescent signal induced by radiation in the ZrO{sub 2}; Influencia de los metales nobles (Pd, Au, Ag) en la senal termoluminiscente inducida por la radiacion en la ZrO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Villa S, G

    2006-07-01

    When increasing the use of the ionizing and non ionizing radiations (for example, gamma and ultraviolet radiation) in different areas of the science and technology, there is necessary to apply more accurate safety measures and to avoid over-exposures that could put in risk the life of workers that manipulate radiation sources, patient that are exposed to this under some medical treatment, as well as materials that undergo intentionally to radiation. Also, the UV radiation that arrives to the earth can cause some damages, to the one to weaken the protector layer of ozone the UV radiation increases that arrives to the earth surface being able to affect the alive beings and the materials. By this so much the development of new materials able to take a census of in a more accurate way, fields of gamma and UV radiation is becoming necessary. In this sense, this work presents the obtained results when quantifying radiation fields, through the analysis in the thermoluminescent behavior (TL) induced by the gamma and UV radiation in the zirconium dioxide synthesized by the sol gel method and doped with nanoparticles of Pd, Au and Ag. It is necessary to mention that in reported works in this respect its mention that the zircon has good thermoluminescent sensitivity induced by these radiation types, however it has shown high thermoluminescent instability that is translated in an important lost of the information after the irradiation. For that through the incorporation of the metallic nanoparticles it was intended to stabilize the TL behavior of zircon. The results showed that the doped zircon has a high sensitivity to the gamma and UV radiation. These also show that the ionizing and non ionizing radiation induce a thermoluminescent curve consisting of two TL peaks with maxima located around 65 C and 145 C and that the intensity is increased with the dose, following a lineal behavior in certain interval of dose exposure that is influenced by the presence of the nanoparticles

  6. Lyman Alpha Control

    CERN Document Server

    Nielsen, Daniel Stefaniak

    2015-01-01

    This document gives an overview of how to operate the Lyman Alpha Control application written in LabVIEW along with things to watch out for. Overview of the LabVIEW code itself as well as the physical wiring of and connections from/to the NI PCI-6229 DAQ box is also included. The Lyman Alpha Control application is the interface between the ALPHA sequencer and the HighFinesse Wavelength Meter as well as the Lyman Alpha laser setup. The application measures the wavelength of the output light from the Lyman Alpha cavity through the Wavelength Meter. The application can use the Wavelength Meter’s PID capabilities to stabilize the Lyman Alpha laser output as well as switch between up to three frequencies.

  7. New ALPHA-2 magnet

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    On 21 June, members of the ALPHA collaboration celebrated the handover of the first solenoid designed for the ALPHA-2 experiment. The magnet has since been successfully installed and is working well.   Khalid Mansoor, Sumera Yamin and Jeffrey Hangst in front of the new ALPHA-2 solenoid. “This was the first of three identical solenoids that will be installed between now and September, as the rest of the ALPHA-2 device is installed and commissioned,” explains ALPHA spokesperson Jeffrey Hangst. “These magnets are designed to allow us to transfer particles - antiprotons, electrons and positrons - between various parts of the new ALPHA-2 device by controlling the transverse size of the particle bunch that is being transferred.” Sumera Yamin and Khalid Mansoor, two Pakistani scientists from the National Centre for Physics in Islamabad, came to CERN in February specifically to design and manufacture these magnets. “We had the chance to work on act...

  8. Plutonium radiation surrogate

    Science.gov (United States)

    Frank, Michael I [Dublin, CA

    2010-02-02

    A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little .alpha.-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.

  9. Alpha Shapes and Proteins

    DEFF Research Database (Denmark)

    Winter, Pawel; Sterner, Henrik; Sterner, Peter

    2009-01-01

    We provide a unified description of (weighted) alpha shapes, beta shapes and the corresponding simplicialcomplexes. We discuss their applicability to various protein-related problems. We also discuss filtrations of alpha shapes and touch upon related persistence issues.We claim that the full...... potential of alpha-shapes and related geometrical constructs in protein-related problems yet remains to be realized and verified. We suggest parallel algorithms for (weighted) alpha shapes, and we argue that future use of filtrations and kinetic variants for larger proteins will need such implementation....

  10. Alpha-particle fluence in radiobiological experiments.

    Science.gov (United States)

    Nikezic, Dragoslav; Yu, Kwan Ngok

    2017-03-01

    Two methods were proposed for determining alpha-particle fluence for radiobiological experiments. The first involved calculating the probabilities of hitting the target for alpha particles emitted from a source through Monte Carlo simulations, which when multiplied by the activity of the source gave the fluence at the target. The second relied on the number of chemically etched alpha-particle tracks developed on a solid-state nuclear track detector (SSNTD) that was irradiated by an alpha-particle source. The etching efficiencies (defined as percentages of latent tracks created by alpha particles from the source that could develop to become visible tracks upon chemical etching) were computed through Monte Carlo simulations, which when multiplied by the experimentally counted number of visible tracks would also give the fluence at the target. We studied alpha particles with an energy of 5.486 MeV emitted from an 241Am source, and considered the alpha-particle tracks developed on polyallyldiglycol carbonate film, which is a common SSNTD. Our results showed that the etching efficiencies were equal to one for source-film distances of from 0.6 to 3.5 cm for a circular film of radius of 1 cm, and for source-film distances of from 1 to 3 cm for circular film of radius of 2 cm. For circular film with a radius of 3 cm, the etching efficiencies never reached 1. On the other hand, the hit probability decreased monotonically with increase in the source-target distance, and fell to zero when the source-target distance was larger than the particle range in air. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  11. Targeted Alpha Therapy: From Alpha to Omega

    International Nuclear Information System (INIS)

    Allen, Barry J; Clarke, Raymond; Huang Chenyu

    2013-01-01

    This review covers the broad spectrum of Targeted Alpha Therapy (TAT) research in Australia; from in vitro and in vivo studies to clinical trials. The principle of tumour anti-vascular alpha therapy (TAVAT) is discussed in terms of its validation by Monte Carlo calculations of vascular models and the potential role of biological dosimetry is examined. Summmary of this review is as follows: 1. The essence of TAT 2. Therapeutic objectives 3. TAVAT and Monte Carlo microdosimetry 4. Biological dosimetry 5. Preclinical studies 6. Clinical trials 7. What next? 8. Obstacles. (author)

  12. Fan-less long range alpha detector

    Science.gov (United States)

    MacArthur, Duncan W.; Bounds, John A.

    1994-01-01

    A fan-less long range alpha detector which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces.

  13. Influencia de las regiones de estabilidad del biorreactor

    OpenAIRE

    Paz Astudillo, Isabel Cristina; Cardona Alzate, Carlos Ariel

    2011-01-01

    Influence of bioreactor stability regions in the efficient production of fuel ethanol Título corto: Influencia de las regiones de estabilidad en la producción de alcohol carburanteResumen Colombia ha desarrollado un proyecto ambicioso en la producción de alcohol carburante, y actualmente es uno de los países líderes de América Latina en la producción de biocombustibles. No obstante, algunas de sus plantas industriales productoras de etanol presentan problemas durante el arranque y la operació...

  14. Influencias de Miguel de Unamuno en Ernesto Sábato

    OpenAIRE

    Hermosilla Sánchez, Alejandro

    2007-01-01

    [ES] El artículo tiene como objetivo estudiar las influencias que el pensamiento de Unamuno ha ejercido sobre la obra de Ernesto Sábato y otros autores argentinos. Para conseguir este objetivo, el artículo analiza la particular interpretación de Unamuno del mito de Caín y Abel y observa cómo la misma ha sido fundamental para delimitar los parámetros a través de los que la literatura argentina y, concretamente, la obra de Sábato trabaja. [EN] The article has like as objective to study the i...

  15. Alpha1-antitrypsin deficiency

    DEFF Research Database (Denmark)

    Stolk, Jan; Seersholm, Niels; Kalsheker, Noor

    2006-01-01

    The Alpha One International Registry (AIR), a multinational research program focused on alpha1-antitrypsin (AAT) deficiency, was formed in response to a World Health Organization recommendation. Each of the nearly 20 participating countries maintains a national registry of patients with AAT defic...... epidemiology, inflammatory and signalling processes, therapeutic advances, and lung imaging techniques....

  16. Alpha clustering in nuclei

    International Nuclear Information System (INIS)

    Hodgson, P.E.

    1990-01-01

    The effects of nucleon clustering in nuclei are described, with reference to both nuclear structure and nuclear reactions, and the advantages of using the cluster formalism to describe a range of phenomena are discussed. It is shown that bound and scattering alpha-particle states can be described in a unified way using an energy-dependent alpha-nucleus potential. (author)

  17. Alpha particles spectrometer with photodiode PIN; Espectrometro de particulas alfa con fotodiodo PIN

    Energy Technology Data Exchange (ETDEWEB)

    Chacon R, A.; Hernandez V, R.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidades Academicas de Estudios Nucleares e Ingenieria Electrica, Calle Cipres No. 10, Fracc. La Penuela, 09869 Zacatecas (Mexico); Ramirez G, J. [Instituto Nacional de Estadistica Geografia e Informatica, Direccion General de Innovacion y Tecnologia de Informacion, Av. Heroes de Nacozari Sur 2301, Fracc. Jardines del Parque, 20276 Aguascalientes (Mexico)], e-mail: achruiz@hotmail.com

    2009-10-15

    The radiation propagates in form of electromagnetic waves or corpuscular radiation; if the radiation energy causes ionization in environment that crosses it is considered ionizing radiation. To detect radiation several detectors types are used, if the radiation are alpha particles are used detectors proportional type or trace elements. In this work the design results, construction and tests of an alpha particles spectrometer are presented, which was designed starting from a photodiode PIN type. The system design was simulated with a code for electronic circuits. With results of simulation phase was constructed the electronic phase that is coupled to a multichannel analyzer. The resulting electronic is evaluated analyzing the electronic circuit performance before an alphas triple source and alpha radiation that produce two smoke detectors of domestic use. On the tests phase we find that the system allows obtain, in a multichannel, the pulses height spectrum, with which we calibrate the system. (Author)

  18. Genetics Home Reference: alpha thalassemia

    Science.gov (United States)

    ... Facebook Twitter Home Health Conditions Alpha thalassemia Alpha thalassemia Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Alpha thalassemia is a blood disorder that reduces the production ...

  19. Gauge-invariant perturbations of varying-alpha cosmologies

    CERN Document Server

    Barrow, J D

    2003-01-01

    Using a gauge-invariant formalism we derive and solve the perturbed cosmological equations for the BSBM theory of varying fine structure 'constant'. We calculate the time evolution of inhomogeneous perturbations of the fine structure constant, delta alpha/alpha on small and large scales with respect to the Hubble radius. In a radiation-dominated universe, small inhomogeneities in alpha will decrease on large scales but on scales smaller than the Hubble radius they will undergo stable oscillations. In a dust-dominated universe small inhomogeneous perturbations in alpha will become constant on large scales and on small scales they will increase as t sup 2 sup / sup 3 , and delta alpha/alpha will track delta rho sub m /rho sub m. If the expansion accelerates, as in the case of a LAMBDA or quintessence-dominated phase, inhomogeneities in alpha will decrease on both large and small scales. The amplitude of perturbations in alpha will be much smaller than that of matter or radiation perturbations. We also present a...

  20. Influence of the spectral distribution of a solar simulator and of the outer diffuse radiation in the estimation of the optical yield of a thermal solar receiver; Influencia de la distribucion espectral de un simulador solar y de la radiacion difusa exterior en la estimacion del rendimiento optico de un captador solar termico

    Energy Technology Data Exchange (ETDEWEB)

    Sallaberry, F.; Garcia de Jalon, A.; Ramirez, L.; Olano, X.; Bernad, I.; Erice, R.

    2008-07-01

    In this paper we will show the results of the analysis of factors that influence the estimation of optical efficiency of solar thermal collectors testes according to the European standard UNE-EN 12975-2. Indoor tests with solar simulator involve control of the spectrum of its lamps to ensure that the difference with the Sun one does not change the optical efficiency {eta}{sub 0} of the collector. For outdoor tests, the diffuse radiation should be control as well. In the laboratory (LCS) of CENER, solar collectors tests are done according to part 6.1 of the standard UNE{sub E}N 12975-2 in continuous solar simulator. This study estimated the spectral correction applied to the estimation of optical efficiency of some solar collectors, with different selective materials. Likewise, we will weight the influence of terms related to diffuse radiation and spectral distribution. (Author)

  1. Effect of alpha particles on bacteriophage T4Br(+)

    International Nuclear Information System (INIS)

    Leonteva, G.A.; Akoev, I.G.; Grigorev, A.E.

    1983-01-01

    The effects of heavy particle radiation, which is believed to be responsible for the high relative biological effectiveness (RBE) of space hadrons, on bacteriophages are investigated. Dry film cultures of bacteriophage T4 were irradiated with 5.3 MeV Po-210 alpha particles to doses from 5 to 60 Gray, and compared with cultures irradiated by Co-60 gamma radiation. Examination of the exponential dose-response curves for bacteriophage survival indicates an RBE of 4.68 for the alpha particles. The r-mutation frequency per 10,000 surviving phages is found to peak at 7.1 at doses between 65 and 85 Gray for gamma radiation, however it declines steadily from a level of 10.2 per 10,000 survivors with increasing dose of alpha radiation. Comparison of the mutation frequencies at the same levels of lethality and the spectra of mutations produced by the two types of radiation indicates alpha and gamma radiation to differ as well in the mechanisms of mutation production. It is concluded that the observed high RBE of space hadrons cannot be explained by the presence of high-energy particles in the secondary radiation. 13 references

  2. Alpha Thalassemia (For Parents)

    Science.gov (United States)

    ... the body has a problem producing alpha globin Beta thalassemia : when the body has a problem producing beta ... Transfusion Blood Test: Hemoglobin Electrophoresis Sickle Cell Disease Beta Thalassemia Blood All About Genetics Prenatal Genetic Counseling Genetic ...

  3. Risk estimates for exposure to alpha emitters

    International Nuclear Information System (INIS)

    1982-07-01

    The primary scope of this report is to evaluate the risk of lung cancer from occupational exposure to short-lived daughters of radon and thoron. The Subcommittee on Risk Estimates considers that inhalation of radon and thoron daughters is the major radiation hazard from alpha radiation in uranium mining. The secondary scope of this report is the consideration of the applicability of the risk estimates derived from miners to the general public. The risk to members of the public from radium-226 in drinking water is also considered. Some research requirments are suggested

  4. ALPHA-2: the sequel

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    While many experiments are methodically planning for intense works over the long shutdown, there is one experiment that is already working at full steam: ALPHA-2. Its final components arrived last month and will completely replace the previous ALPHA set-up. Unlike its predecessor, this next generation experiment has been specifically designed to measure the properties of antimatter.   The ALPHA team lower the new superconducting solenoid magnet into place. The ALPHA collaboration is working at full speed to complete the ALPHA-2 set-up for mid-November – this will give them a few weeks of running before the AD shutdown on 17 December. “We really want to get some experience with this device this year so that, if we need to make any changes, we will have time during the long shutdown in which to make them,” says Jeffrey Hangst, ALPHA spokesperson. “Rather than starting the 2014 run in the commissioning stage, we will be up and running from the get go.&...

  5. Expression of triplicated and quadruplicated alpha globin genes in sheep.

    Science.gov (United States)

    Vestri, R; Pieragostini, E; Yang, F; di Gregorio, P; Rando, A; Masina, P

    1991-01-01

    In the sheep alpha alpha alpha globin gene haplotype, the three genes display from the 5' to the 3' end the percentage efficiencies of about 30:14:6, as indicated by the amounts of the three types of alpha chain produced in the alpha alpha alpha/alpha alpha alpha homozygotes. The 3' gene in the alpha alpha alpha alpha haplotype appears to have an efficiency around 1%, as suggested by analysis of one quadruple alpha homozygote. Moreover, the total outputs of the alpha alpha alpha as well as of the alpha alpha alpha alpha haplotypes do not substantially differ from that of the common alpha alpha haplotype.

  6. Influencia de los cambios posturales en el electrocardiograma

    Directory of Open Access Journals (Sweden)

    Giuseppe Lanza

    2014-04-01

    Full Text Available Diferentes posiciones del cuerpo tienen influencia demostrada en los cambios de trazo de un electrocardiograma: alteración de la respiración, cambios en el vectocardiograma, posiciones de los brazos y segmento ST, posición del cuerpo y el síndrome de QT largo, alteración del voltaje de R, onda Q y eje eléctrico, colocación inadecuada de electrodos, entre otros aspectos. En este artículo se realiza una revisión global a fin de llamar la atención en aquellos cambios del trazo del electrocardiograma que pudieran interpretarse de manera inadecuada o atribuirse a patología inexistente.

  7. Influencia de los cambios posturales en el electrocardiograma

    Directory of Open Access Journals (Sweden)

    Giuseppe Lanza

    2014-03-01

    Full Text Available Diferentes posiciones del cuerpo tienen influencia demostrada en los cambios de trazo de un electrocardiograma: alteración de la respiración, cambios en el vectocardiograma, posiciones de los brazos y segmento ST, posición del cuerpo y el síndrome de QT largo, alteración del voltaje de R, onda Q y eje eléctrico, colocación inadecuada de electrodos, entre otros aspectos. En este artículo se realiza una revisión global a fin de llamar la atención en aquellos cambios del trazo del electrocardiograma que pudieran interpretarse de manera inadecuada o atribuirse a patología inexistente.

  8. The effects and control of radiation

    International Nuclear Information System (INIS)

    Saunders, P.A.H.

    1982-12-01

    The subject is discussed under the headings: introduction; ionising radiation (alpha and beta particles, gamma- and X-radiation, neutrons, half-life, sources of radiation); biological effects; risk estimates (somatic) (early effects, delayed effects); risk estimates (hereditary); control of radiation; risk estimates (accidents). (U.K.)

  9. Evaluating the effect of gamma radiation ({sup 60}Co) on protein arcelin and its influence in the resistance of Zabrotes subfasciatus (Boh., 1833) (Coleoptera: Bruchidae); Avaliacao do efeito da radiacao gama ({sup 60}Co) sobre a proteina arcelina e sua influencia na resistencia a Zabrotes subsfasciatus (Boh., 1833) (Coleoptera: Bruchidae)

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Valeria Wanderley

    1998-07-01

    The objective of this research was to evaluate the effects of different gamma doses of Cobalt-60 on arcelin protein in the manifestation of resistance to Zabrotes subfasciatus (Boh., 1833). Seeds of four lines of Phaseolus vulgaris carriers of arcelin protein (Arcelin-1, Arcelin-2, Arcelin-3 and Arcelin-4) and a cultivar without this protein were used as control (IAC-Carioca Akyta) obtained from the Instituto Agronomico do Estado de Sao Paulo - Nucleo Experimental de Campinas (IAC), were irradiated in a source of Cobalt-60, of the panoramic type, from the Instituto de Pesquisas Energeticas e Nucleares/CNEN/SP. The activity was approximately 2218.79 Ci, and the dose rate 0.678 kGy/h. The doses used were 0; 0.25; 0.5; 1.0 and 2.0 kGy. The results showed that the radiation doses did not influence the parameters evaluated in the resistance because a high degree of antibiose in the Arcelin-1 and Arcelin-2 lines was maintained. The Arcelin-3 and Arcelin-4 lines also maintained their behavior less expressive of resistance by antibiose only prolonging the period from egg to adult. The electrophoretic analysis of the lines and cultivar were not changed in relation to the radiation doses. But there was a decrease in relation to the intensity of color of the bands (absorbance) with the increase of the doses. (author)

  10. Ionizing radiation and neoplasia

    International Nuclear Information System (INIS)

    Fajardo, L.F.

    1986-01-01

    Among the well accepted causes of neoplasia, ionizing radiation is quite prominent. Its oncogenic role was suspected by a few pioneers in the field of radiation biology, and some evidence for its oncogenicity has been available for almost 80 years. Since then unquestionable and abundant proof, statistical and experimental, has linked radiation with multiple tumors in mammals. Other forms of radiation (e.g., ultraviolet) are also causally related to neoplasia. This review, however, refers only to the tumors associated with ionizing radiation, either electromagnetic (i.e., gamma and x-rays) or particulate (alpha particles, neutrons, etc.). The field of radiation oncogenesis can be compared to a sea of hypotheses, with a few solid islands of facts. This paper considers the facts (specific radiation-induced neoplasms, risk data, etc.) and then considers some of the hypotheses (possible mechanisms of radiation oncogenesis)

  11. Performance of an alpha air monitor in a dusty environment

    International Nuclear Information System (INIS)

    Hoover, M.D.; Newton, G.J.; Yeh, H.C.; Seiler, F.A.; Boecker, B.B.

    1988-01-01

    The Eberline Alpha-6 Continuous Air Monitor (CAM) was evaluated for use in detecting alpha radiation from 238 Pu and 239 Pu in the presence of background aerosols of salt dust and radon progeny. The Alpha-6 method uses an embedded, multichannel analyzer and real-time computer to correct for the presence of alpha-emitting radon progeny and to accurately report plutonium air concentration in dust-free environments. However, accumulation of mg/cm 2 salt dust on the sample collection filter was found to be equivalent to an infinitely thick layer. Dust loading raises the limit of detection in proportion to the concentration of airborne salt. Proper detection of 239 Pu is impaired by airborne concentrations of salt greater than 2 mg/m 3 . Alpha spectral analysis at a central monitoring computer is recommended to avoid detection errors at higher salt concentrations. (author)

  12. Monte Carlo alpha calculation

    Energy Technology Data Exchange (ETDEWEB)

    Brockway, D.; Soran, P.; Whalen, P.

    1985-01-01

    A Monte Carlo algorithm to efficiently calculate static alpha eigenvalues, N = ne/sup ..cap alpha..t/, for supercritical systems has been developed and tested. A direct Monte Carlo approach to calculating a static alpha is to simply follow the buildup in time of neutrons in a supercritical system and evaluate the logarithmic derivative of the neutron population with respect to time. This procedure is expensive, and the solution is very noisy and almost useless for a system near critical. The modified approach is to convert the time-dependent problem to a static ..cap alpha../sup -/eigenvalue problem and regress ..cap alpha.. on solutions of a/sup -/ k/sup -/eigenvalue problem. In practice, this procedure is much more efficient than the direct calculation, and produces much more accurate results. Because the Monte Carlo codes are intrinsically three-dimensional and use elaborate continuous-energy cross sections, this technique is now used as a standard for evaluating other calculational techniques in odd geometries or with group cross sections.

  13. Cambios en la viabilidad de dos bacterias marinas antárticas expuestas a la radiación solar en la columna de agua: influencia de la mezcla vertical Changes in viability of two Antarctic marine bacteria exposed to solar radiation in the water column: influence of vertical mixing

    Directory of Open Access Journals (Sweden)

    E. A. Hernández

    2007-09-01

    Full Text Available Se estudió el efecto de la radiación ultravioleta (RUV sobre dos cepas bacterianas marinas antárticas (UVps y UVvi en la columna de agua de la caleta Potter (Shetland del Sur, Antártida. Frascos de cuarzo con las cepas en estudio fueron expuestos a la radiación solar en superficie, a 1 m y a 3 m de profundidad. Se realizaron ensayos con exposición directa y con filtros interferenciales que discriminaron la radiación UVA y la UVB. En otros ensayos se simuló una mezcla vertical de 4 m/h. Ambas cepas mostraron una disminución significativa del número de unidades formadoras de colonias, tanto en superficie como a 1 m de profundidad, luego de exponerlas a dosis superficiales de UVB de 8,4 kJ m-2. El estudio con filtros interferenciales mostró una disminución significativa de la viabilidad en ambos tratamientos UV en superficie y a 1 m. La cepa UVps mostró mayor sensibilidad a la UVB que a la UVA. La mezcla vertical amortiguó el daño causado por la UVB cuando la dosis en superficie fue de 4,8 kJ m-2. Este efecto amortiguador no se observó cuando la dosis en superficie fue de 7,7 kJ m-2. Estos resultados muestran que el efecto negativo de la RUV sobre el bacterioplancton sería particularmente importante en el primer metro de profundidad de las aguas costeras antárticas con abundante material particulado en suspensión.The effect of UV radiation on two Antarctic marine bacterial strains (UVps and UVvi was studied in the water column of Potter Cove (South Shetland, Antarctica. Quartz flasks were filled with the bacterial suspensions and exposed to solar radiation at 0 m, 1 m and 3 m depth. Assays using flasks exposed to direct solar radiation and others using flasks covered with/by interferential filters which discriminate between UVA and UVB, were performed. In other assays, a vertical mixing of 4 m/h was simulated. Both strains showed a significant decrease in viability (expressed as colony - forming units when exposed to a surface

  14. Alpha contamination assessment for D ampersand D activities: Technology overview

    International Nuclear Information System (INIS)

    Conaway, J.G.; Rawool-Sullivan, M.W.; MacArthur, D.W.

    1996-02-01

    Instruments based on the principle of Long-Range Alpha Detection (LRAD) detect the ions created in ambient air by Ionizing radiation, particularly alpha radiation, interacting with air molecules. Using either an electrostatic field or forced convection, these ions can be transported to a detection grid where the ions produce a small current that is measured with a sensitive electrometer. LRAD-based instruments can give separate, simultaneous measurements of alpha-emitting solids and inert radioactive gases such as radon. LRAD-based instruments assess surface contamination on an entire object or large surface area in a single, rapid measurement, including relatively inaccessible areas such as interior surfaces of pipes and process equipment. The LRAD concept is well proven and has been developed into a range of different radiation detection devices. This paper presents an overview of the technology, while several associated papers explore specific applications in greater detail

  15. Single and double grid long-range alpha detectors

    International Nuclear Information System (INIS)

    MacArthur, D.W.; Allander, K.S.

    1993-01-01

    Alpha particle detectors capable of detecting alpha radiation from distant sources. In one embodiment, a voltage is generated in a single electrically conductive grid while a fan draws air containing air molecules ionized by alpha particles through an air passage and across the conductive grid. The current in the conductive grid can be detected and used for measurement or alarm. Another embodiment builds on this concept and provides an additional grid so that air ions of both polarities can be detected. The detector can be used in many applications, such as for pipe or duct, tank, or soil sample monitoring

  16. Health effects of ionizing radiation

    International Nuclear Information System (INIS)

    Pathak, B.

    1989-12-01

    Ionizing radiation is energy that travels through space as electromagnetic waves or a stream of fast moving particles. In the workplace, the sources of ionizing radiation are radioactive substances, nuclear power plants, x-ray machines and nuclear devices used in medicine, research and industry. Commonly encountered types of radiation are alpha particles, beta particles and gamma rays. Alpha particles have very little penetrating power and pose a risk only when the radioactive substance is deposited inside the body. Beta particles are more penetrating than alpha particles and can penetrate the outer body tissues causing damage to the skin and the eyes. Gamma rays are highly penetrating and can cause radiation damage to the whole body. The probability of radiation-induced disease depends on the accumulated amount of radiation dose. The main health effects of ionizing radiation are cancers in exposed persons and genetic disorders in the children, grandchildren and subsequent generations of the exposed parents. The fetus is highly sensitive to radiation-induced abnormalities. At high doses, radiation can cause cataracts in the eyes. There is no firm evidence that ionizing radiation causes premature aging. Radiation-induced sterility is highly unlikely for occupational doses. The data on the combined effect of ionizing radiation and other cancer-causing physical and chemical agents are inconclusive

  17. Radiation monitoring by minicomputer

    International Nuclear Information System (INIS)

    Seamons, M.

    1977-01-01

    Radiation monitoring at the Los Alamos Scientific Laboratory (LASL) ranges from measuring the potential build-up of alpha particle radiation in the offices and laboratories of LASL to the detection of radiation leakage from nuclear tests at the Nevada Test Site (NTS). This paper describes PDP-11 based systems to accomplish both types of monitoring. In the first system, filter papers are collected from monitoring stations around LASL. One filter paper is placed under any of 128 photomultiplier (PM) tubes exposing it to alpha radiation. Alpha particle ''hits'' are recorded in a 64-word hardware FIFO, which interrupts and is read by the computer. The FIFO makes it possible to handle short aggregate alpha particle bursts of up to 10 6 hits/s in a computer that can only process 10 4 hits/s. In the second system, up to 100 current measuring radiation probes feed data from the site of the nuclear test(s) to the computer by microwave. The software system can support three tests simultaneously. Both systems offer a high degree of flexibility in configuring for a new test and in real-time control of such things as channel assignment, selective data retrieval, and output formatting

  18. Monte Carlo alpha deposition

    International Nuclear Information System (INIS)

    Talley, T.L.; Evans, F.

    1988-01-01

    Prior work demonstrated the importance of nuclear scattering to fusion product energy deposition in hot plasmas. This suggests careful examination of nuclear physics details in burning plasma simulations. An existing Monte Carlo fast ion transport code is being expanded to be a test bed for this examination. An initial extension, the energy deposition of fast alpha particles in a hot deuterium plasma, is reported. The deposition times and deposition ranges are modified by allowing nuclear scattering. Up to 10% of the initial alpha particle energy is carried to greater ranges and times by the more mobile recoil deuterons. 4 refs., 5 figs., 2 tabs

  19. Buffett’s Alpha

    DEFF Research Database (Denmark)

    Frazzini, Andrea; Kabiller, David; Heje Pedersen, Lasse

    Berkshire Hathaway has realized a Sharpe ratio of 0.76, higher than any other stock or mutual fund with a history of more than 30 years, and Berkshire has a significant alpha to traditional risk factors. However, we find that the alpha becomes insignificant when controlling for exposures to Betting......-Against-Beta and Quality-Minus-Junk factors. Further, we estimate that Buffett’s leverage is about 1.6-to-1 on average. Buffett’s returns appear to be neither luck nor magic, but, rather, reward for the use of leverage combined with a focus on cheap, safe, quality stocks. Decomposing Berkshires’ portfolio into ownership...

  20. Influence of gamma radiation in the mechanical properties of partially biodegradable foams of PP/HMSP blends with sugar cane bagasse; Influencia da irradiacao gama nas propriedades mecanicas de espumas parcialmente biodegradaveis de blendas de PP/HMSPP com bagaco de cana-de-acucar

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Elizabeth C.L.; Scagliusi, Sandra R.; Mascarenha, Yago; Lugao, Ademar B., E-mail: eclcardo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Polymers are used in various applications and in different market segments generating enormous amounts of wastes in environment. Among residues components in landfills are polymeric materials, as PP, contributing with 20 to 30% of total solids residues. As polymeric materials are immune to microbial degradation, remain in soil and in landfills as a semi-permanent residue. Environmental concerning toward residues reduction is nowadays directed to the development of renewable polymers for manufacturing of materials that degrade under environment, as biodegradable polymeric foams. High density structural foams are especially used in civil construction, replacing metals, woods and concrete, with a major purpose of materials cost reduction. This work aims to the study of biodegradability in PP/HMSPP blends with sugarcane bagasse at 10, 15, 30 and 50% further irradiated at 50, 100, 150 and 200 kGy doses. The biodegradability was assessed via Soil Burial Test. Tensile strength and elongation at break results proved that natural fibers reinforcement characteristic was not affected by gamma radiation, responsible by degradation and consequent biodegradability acceleration in structural foams. (author)

  1. Case Study - Alpha

    Directory of Open Access Journals (Sweden)

    Stephen Leybourne

    2016-11-01

    Full Text Available This case study was developed from an actual scenario by Dr. Steve Leybourne of Boston University.  The case documents the historical evolution of an organization, and has been used successfully in courses dealing with organizational and cultural change, and the utilization of ‘soft skills’ in project-based management. This is a short case, ideal for classroom use and discussion.  The issues are easily accessible to students, and there is a single wide ranging question that allows for the inclusion of many issues surrounding strategic decision-making, and behavioural and cultural change. Alpha was one of the earlier companies in the USA to invest in large, edge-of-town superstores, with plentiful free vehicle parking, selling food and related household products. Alpha was created in the 1950s as a subsidiary of a major publicly quoted retail group.  It started business by opening a string of very large discount stores in converted industrial and warehouse premises in the south of the United States. In the early days shoppers were offered a limited range of very competitively priced products. When Alpha went public in 1981 it was the fourth largest food retailer in the US, selling an ever-widening range of food and non-food products.  Its success continued to be based on high volume, low margins and good value for money, under the slogan of ‘Alpha Price.’

  2. Alpha-mannosidosis

    DEFF Research Database (Denmark)

    Borgwardt, Line; Stensland, Hilde Monica Frostad Riise; Olsen, Klaus Juul

    2015-01-01

    of the three subgroups of genotype/subcellular localisation and the clinical and biochemical data were done to investigate the potential relationship between genotype and phenotype in alpha-mannosidosis. Statistical analyses were performed using the SPSS software. Analyses of covariance were performed...

  3. Radiation carcinogenesis, laboratory studies

    International Nuclear Information System (INIS)

    Shellabarger, C.J.

    1974-01-01

    Laboratory studies on radioinduced carcinogenesis are reviewed. Some topics discussed are: radioinduced neoplasia in relation to life shortening; dose-response relationships; induction of skin tumors in rats by alpha particles and electrons; effects of hormones on tumor response; effects of low LET radiations delivered at low dose-rates; effects of fractionated neutron radiation; interaction of RBE and dose rate effects; and estimates of risks for humans from animal data. (U.S.)

  4. Applications of the Long-Range Alpha Detector (LRAD) technology to low-level radioactive waste management

    International Nuclear Information System (INIS)

    Johnson, J.D.; Allander, K.S.; Bounds, J.A.; Garner, S.E.; Johnson, J.P.; MacArthur, D.W.

    1993-01-01

    Long-Range Alpha Detector (LRAD) systems are designed to monitor alpha contamination by measuring the number of ions in the air. Alpha particles are a form of ionizing radiation and a typical 5-MeV alpha particle will create about 150,000 ion pairs in air. Field tests at various DOE sites have shown that LRAD Surface Soil Monitors (SSM), Sample Monitors, and Object Monitors are faster and more sensitive than traditional alpha detectors for measuring alpha contamination. This paper discusses the various applications of LRAD technology to low-level radioactive waste management

  5. Demystifying AlphaGo Zero as AlphaGo GAN

    OpenAIRE

    Dong, Xiao; Wu, Jiasong; Zhou, Ling

    2017-01-01

    The astonishing success of AlphaGo Zero\\cite{Silver_AlphaGo} invokes a worldwide discussion of the future of our human society with a mixed mood of hope, anxiousness, excitement and fear. We try to dymystify AlphaGo Zero by a qualitative analysis to indicate that AlphaGo Zero can be understood as a specially structured GAN system which is expected to possess an inherent good convergence property. Thus we deduct the success of AlphaGo Zero may not be a sign of a new generation of AI.

  6. $\\alpha$-Representation for QCD

    OpenAIRE

    Tuan, Richard Hong

    1998-01-01

    An $\\alpha$-parameter representation is derived for gauge field theories.It involves, relative to a scalar field theory, only constants and derivatives with respect to the $\\alpha$-parameters. Simple rules are given to obtain the $\\alpha$-representation for a Feynman graph with an arbitrary number of loops in gauge theories in the Feynman gauge.

  7. Alpha Theta Meditation: Phenomenological, neurophysiologic ...

    African Journals Online (AJOL)

    Alpha Theta Meditation: Phenomenological, neurophysiologic, mindfulness, mood, health and sport implications. ... the single alpha theta meditation was associated with elevated alpha and theta activity, as well as decrease in negative mood perceptions, especially with regard to anxiety, sadness and confusion scores.

  8. Alpha scintillation radon counting

    International Nuclear Information System (INIS)

    Lucas, H.F. Jr.

    1977-01-01

    Radon counting chambers which utilize the alpha-scintillation properties of silver activated zinc sulfide are simple to construct, have a high efficiency, and, with proper design, may be relatively insensitive to variations in the pressure or purity of the counter filling. Chambers which were constructed from glass, metal, or plastic in a wide variety of shapes and sizes were evaluated for the accuracy and the precision of the radon counting. The principles affecting the alpha-scintillation radon counting chamber design and an analytic system suitable for a large scale study of the 222 Rn and 226 Ra content of either air or other environmental samples are described. Particular note is taken of those factors which affect the accuracy and the precision of the method for monitoring radioactivity around uranium mines

  9. Combining Alphas via Bounded Regression

    Directory of Open Access Journals (Sweden)

    Zura Kakushadze

    2015-11-01

    Full Text Available We give an explicit algorithm and source code for combining alpha streams via bounded regression. In practical applications, typically, there is insufficient history to compute a sample covariance matrix (SCM for a large number of alphas. To compute alpha allocation weights, one then resorts to (weighted regression over SCM principal components. Regression often produces alpha weights with insufficient diversification and/or skewed distribution against, e.g., turnover. This can be rectified by imposing bounds on alpha weights within the regression procedure. Bounded regression can also be applied to stock and other asset portfolio construction. We discuss illustrative examples.

  10. A Critical Review of Alpha Radionuclide Therapy : How to Deal with Recoiling Daughters?

    NARCIS (Netherlands)

    De Kruijff, R.M.; Wolterbeek, H.T.; Denkova, A.G.

    2015-01-01

    This review presents an overview of the successes and challenges currently faced in alpha radionuclide therapy. Alpha particles have an advantage in killing tumour cells as compared to beta or gamma radiation due to their short penetration depth and high linear energy transfer (LET). Touching

  11. Image Guidance and Assessment of Radiation Induced Gene Therapy

    National Research Council Canada - National Science Library

    Pelizzari, Charles

    2004-01-01

    Image guidance and assessment techniques are being developed for combined radiation/gene therapy, which utilizes a radiation-inducible gene promoter to cause expression of tumor necrosis factor alpha...

  12. Early and continuing effects of combined alpha and beta irradiation of the lung:

    Energy Technology Data Exchange (ETDEWEB)

    Scott, B.R.; Hahn, F.F.; Snipes, M.B.; Newton, G.J.; Eidson, A.F.; Mauderly, J.L.; Boecker, B.B.

    1988-03-01

    This report summarizes an inhalation exposure experiment that concerns early and continuing effects of combined alpha and beta irradiation of the lung of rats. Both morbidity at 18 months and mortality within 18 months after exposure were examined for rats exposed to the beta-emitter /sup 147/Pm, the alpha-emitter /sup 238/Pu, or both combined. The results were used to validate hazard-function models that were developed (1)for pulmonary functional morbidity at 18 months and (2) for lethality from radiation pneumonitis and pulmonary fibrosis within 18 months. Both models were found to adequately predict the experimental observations after combined chronic alpha and beta irradiation of the lung. A relative biological effectiveness of approximately 7 was obtained for /sup 238/Pu alpha radiation compared to /sup 147/Pm beta radiation for both pulmonary functional morbidity and lethality from radiation pneumonitis and pulmonary fibrosis. 12 refs., 16 figs., 11 tabs.

  13. Radiation protection and the safety of radiation sources

    International Nuclear Information System (INIS)

    1996-01-01

    These Safety Fundamentals cover the protection of human beings against ionizing radiation (gamma and X rays and alpha, beta and other particles that can induce ionization as they interact with biological materials), referred to herein subsequently as radiation, and the safety of sources that produce ionizing radiation. The Fundamentals do not apply to non-ionizing radiation such as microwave, ultraviolet, visible and infrared radiation. They do not apply either to the control of non-radiological aspects of health and safety. They are, however, part of the overall framework of health and safety

  14. Dosimetry of natural and man-made alpha emitters in plankton

    International Nuclear Information System (INIS)

    Paschoa, A.S.; Baptista, G.B.; Wrenn, M.E.; Eisenbrid, M.

    1980-11-01

    Comparison between the natural and man-made alpha radiation dose rates to plankton can be important for predicting the potential long-term effects on aquatic biota resulting from the routine or accidental radioactive releases from the nuclear fuel cycle. A contribution is made here towards the goal of comparing natural with man-made alpha radiation dose rates to plankton using the same method of calculation in both cases. (Author) [pt

  15. Radiation measurement instruments

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The requirements and characteristics of radiation measurement instruments vary according to the circumstances under which they are used (field, area, laboratory conditions) and according to their purpose (radiation survey, personal monitoring, use in emergencies, or alpha, beta or gamma counting). In fact, radiation measurement instruments are so varied that only an overview has been presented here. Groups of instruments for these and other conditions or uses are presented in tabular form together with their operational characteristics and requirements. While examples of calibrations, efficiencies and variability of all the listed instruments are not given in this chapter, these parameters are illustrated for the most important types of gamma and beta survey instruments, in some cases with a specific instrument used as an example. Some of the important parameters that need to be considered for laboratory counting of alpha and beta particles are presented. Charts for determination of optimum sample and background counting times, errors and statistics are given

  16. Vico y Sarmiento: un caso para el tema de las influencias

    OpenAIRE

    Lértora Mendoza, Celina A.

    1993-01-01

    Sarmiento y la Generación del ‘37 no fueron viquianos, pero realizaron una obra histórica y civilizadora acorde con los ideales de Vico, que vivió y pensó en un contexto muy diferente. El tema de la influencia de Vico en Sarmiento es algo a debatir, lo cual requiere una depuración metodológica y una explicitación teórica de las posibles conexiones. Las cuestiones que solicitan el presente estudio remiten a la pregunta sobre esa posible influencia en el pensador argentino: si hay objetivamente...

  17. La influencia de Gregorio Magno en Alberto Magno: Super Dionysii Mysticam Theologiam et Epistulas

    OpenAIRE

    Anneliese Meis

    2010-01-01

    Si bien la influencia de Gregorio Magno fue decisiva para la historia del pensamiento teológico práctico en la Edad Media, siendo Gregorio el autor más citado en la STh de Tomás de Aquino después de Agustín, su influencia sobre Alberto Magno no ha sido estudiada recientemente. En efecto, Alberto Magno orienta su Comentario al Corpus Dionisiacum de la misma manera que Gregorio por la revelación de este misterio, que busca entender racionalmente. El estudio se detiene en las citas tomadas por e...

  18. Los inicios del astillero de la Habana en el siglo XVIII y la influencia francesa

    OpenAIRE

    Serrano Alvarez,José Manuel

    2011-01-01

    Este trabajo trata de establecer la influencia francesa en los inicios del astillero de La Habana durante el siglo XVIII. Aunque se ha defendido una influencia francesa muy escasa en los aspectos navales, en este trabajo se trata de mostrar cómo las ideas francesas fueron muy influyentes tanto para el ámbito general de la Marina española del siglo XVIII como para el astillero de La Habana en concreto. Las reformas francesas a nivel económico y administrativo fueron claves para entender el éxi...

  19. Treatment of alpha bearing wastes

    International Nuclear Information System (INIS)

    1988-01-01

    This report deals with the current state of the art of alpha waste treatment, which is an integral part of the overall nuclear waste management system. The International Atomic Energy Agency (IAEA) defines alpha bearing waste as 'waste containing one or more alpha emitting radionuclides, usually actinides, in quantities above acceptable limits'. The limits are established by national regulatory bodies. The limits above which wastes are considered as alpha contaminated refer to the concentrations of alpha emitters that need special consideration for occupational exposures and/or potential safety, health, or environmental impact during one or more steps from generation through disposal. Owing to the widespread use of waste segregation by source - that is, based upon the 'suspect origin' of the material - significant volumes of waste are being handled as alpha contaminated which, in fact, do not require such consideration by reason of risk or environmental concern. The quantification of de minimis concepts by national regulatory bodies could largely contribute to the safe reduction of waste volumes and associated costs. Other factors which could significantly contribute to the reduction of alpha waste arisings are an increased application of assaying and sorting, instrumentation and the use of feedback mechanisms to control or modify the processes which generate these wastes. Alpha bearing wastes are generated during fabrication and reprocessing of nuclear fuels, decommissioning of alpha contaminated facilities, and other activities. Most alpha wastes are contact handled, but a small portion may require shielding or remote handling because of high levels of neutron (n), beta (β), or gamma (γ) emissions associated with the waste material. This report describes the sources and characteristics of alpha wastes and strategies for alpha waste management. General descriptions of treatment processes for solid and liquid alpha wastes are included. 71 refs, 14 figs, 9 tabs

  20. The alpha effect

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    Much of the recent interest in RAM system reliability stems from concern over alpha particle soft error rates reported for the initial 64 k RAMs. With increasing memory density likely in the next few years the problem of soft errors is rearing its head again. A few years ago ITT carried out experiments on 16k RAMs and found no significant problems. However, recent tests have shown a raise in the number of soft errors with 64k RAMs, and the launch of 256k and 512k memories is likely to make the problem acute

  1. Alpha-mannosidosis

    Directory of Open Access Journals (Sweden)

    Nilssen Øivind

    2008-07-01

    Full Text Available Abstract Alpha-mannosidosis is an inherited lysosomal storage disorder characterized by immune deficiency, facial and skeletal abnormalities, hearing impairment, and intellectual disability. It occurs in approximately 1 of 500,000 live births. The children are often born apparently normal, and their condition worsens progressively. Some children are born with ankle equinus or develop hydrocephalus in the first year of life. Main features are immune deficiency (manifested by recurrent infections, especially in the first decade of life, skeletal abnormalities (mild-to-moderate dysostosis multiplex, scoliosis and deformation of the sternum, hearing impairment (moderate-to-severe sensorineural hearing loss, gradual impairment of mental functions and speech, and often, periods of psychosis. Associated motor function disturbances include muscular weakness, joint abnormalities and ataxia. The facial trait include large head with prominent forehead, rounded eyebrows, flattened nasal bridge, macroglossia, widely spaced teeth, and prognathism. Slight strabismus is common. The clinical variability is significant, representing a continuum in severity. The disorder is caused by lysosomal alpha-mannosidase deficiency. Alpha-mannosidosis is inherited in an autosomal recessive fashion and is caused by mutations in the MAN2B1 gene located on chromosome 19 (19 p13.2-q12. Diagnosis is made by measuring acid alpha-mannosidase activity in leukocytes or other nucleated cells and can be confirmed by genetic testing. Elevated urinary secretion of mannose-rich oligosaccharides is suggestive, but not diagnostic. Differential diagnoses are mainly the other lysosomal storage diseases like the mucopolysaccharidoses. Genetic counseling should be given to explain the nature of the disease and to detect carriers. Antenatal diagnosis is possible, based on both biochemical and genetic methods. The management should be pro-active, preventing complications and treating

  2. Application of Micro-coprecipitation Method to Alpha Source Preparation for Measuring Alpha Nuclides

    International Nuclear Information System (INIS)

    Lee, Myung Ho; Park, Jong Ho; Oh, Se Jin; Song, Byung Chul; Song, Kyuseok

    2011-01-01

    Among the source preparations, an electrodeposition is a commonly used method for the preparation of sources for an alpha spectrometry, because this technique is simple and produces a very thin deposit, which is essential for a high resolution of the alpha peak. Recently, micro-coprecipitation with rare earths have been used to yield sources for -spectrometry. In this work, the Pu, Am and Cm isotopes were purified from hindrance nuclides and elements with an a TRU resin in radioactive waste samples, and the activity concentrations of the Pu, Am and Cm isotopes were determined by radiation counting methods after alpha source preparation like micro coprecipitation. After the Pu isotopes in the radioactive waste samples were separated from the other nuclides with an anion exchange resin, the Am isotopes were purified with a TRU resin and an anion exchange resin or a TRU resin. Activity concentrations and chemical recoveries of 241 Am purified with the TRU resin were similar to those with the TRU resin and anion exchange resin. In this study, to save on the analytical time and cost, the Am isotopes were purified with the TRU resin without using an additional anion exchange resin. After comparing the electrodeposition method with the micro-coprecipitation method, the micro-coprecipitation method was used for the alpha source preparation, because the micro-coprecipitation method is simple and more reliable for source preparation of the Pu, Am and Cm isotopes

  3. Alpha activity measurement with lsc

    International Nuclear Information System (INIS)

    Dobrin, R. I.; Dulama, C. N.; Ciocirlan, C. N.; Toma, A.; Stoica, S. M.; Valeca, M.

    2013-01-01

    Recently, we showed that the alpha activity in liquid samples can be measured using a liquid scintillation analyzer without alpha/beta discrimination capability. The purpose of this work was to evaluate the performances of the method and to optimize the procedure of the sample preparation. A series of tests was performed to validate the procedure of alpha emitting radionuclides extraction in aqueous samples with Actinide Resin, especially regarding to the contact time required to extract all alpha nuclides. The main conclusions were that a minimum 18 hours stirring time is needed to achieve a percent recovery of the alpha nuclides grater than 90% and that the counting efficiency of alphas measurements with LSC is nearly 100%. (authors)

  4. Environmental radiation

    International Nuclear Information System (INIS)

    2008-01-01

    The types of ionizing radiations from the atomic nucleus are explained, such as the beams alpha, beta and gamma. The definitions of spectrometry and nuclear traces have been included.The study presents two researches realized in Costa Rica on the radioactive nuclear and artificial elements in the environment. The first shown is the analysis of coastal sediments where explains which are radioactive artificial isotopes and the pollution that occurs in food, coastal sediments, fertilizers, the soil, the water and the air. Within the analysis techniques are the gamma spectrometry, alpha spectrometry and nuclear strokes. Among the conclusions of this initial investigation is shown that at Punta Leona descendants of Uranium and Thorium present lower concentrations in relation to the gulf and its variations are not important. In the following study the radon gas is analyzed in the human environment where is determined that it is the second generator that causes cancer in lungs after the tobacco. This work indicates that the doses come from natural and artificial sources of radiation for the public are a whole of 2.7 mSv/year, information provided by the UNSCEAR, 2000. The radon gas is inert and radioactive of atomic number 86, includes 23 isotopes and 3 natural isotopes. The radon is everywhere, as are houses and buildings, in Costa Rica it is located in old homes with little ventilation. It describes the equipment used for the detection of radon gas in the environment. Within the conclusions radon gas is concentrated in confined spaces which can be harmful to health. It is determined that enough ventilation in places of high concentrations of radon is important. Finally it is recommended to monitor the sites where can be detected high concentrations of radon and that they have important influx of people [es

  5. Absolute measurements of the alpha-gamma emitters activities by a sum-coincidence method

    International Nuclear Information System (INIS)

    Tobias, C.C.B.

    1982-01-01

    The absolute activity of U-235 contained in a UO 2 sample, using a sum-coincidence circuit which selected only the alpha particles which were simultaneous with the well known 184 Kev gamma radiation from Th-231. The alpha particles were detected by ZnS(Ag) scintillator specially designed to show its maximun efficiency for U-235 alpha particles, whereas the gamma radiation was detected by NaI(Tl) scintillation detector. The values obtained for the half-life of U-235 was compared with data from various observers using different experimental techniques. (Author) [pt

  6. Radiation protection measuring device SSM-1

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    Product information from the producer on a universal measuring instrument for alpha, beta and gamma radiation designed for stationary and field use by military, police and fire brigades. 4 figs. (qui)

  7. Alpha Emitting Radionuclides and Radiopharmaceuticals for Therapy

    International Nuclear Information System (INIS)

    Chérel, Michel; Barbet, Jacques

    2013-01-01

    Today, cancer treatments mainly rely on surgery or external beam radiation to remove or destroy bulky tumors. Chemotherapy is given when tumours cannot be removed or when dissemination is suspected. However, these approaches cannot permanently treat all cancers and relapse occurs in up to 50% of the patients’ population. Radioimmunotherapy (RIT) and peptide receptor radionuclide therapy (PRRT) are effective against some disseminated and metastatic diseases, although they are rarely curative. Most preclinical and clinical developments in this field have involved electron-emitting radionuclides, particularly iodine-131, yttrium-90 and lutetium-177. The large range of the electrons emitted by these radionuclides reduces their efficacy against very small tumour cell clusters or isolated tumour cells present in residual disease and in many haematological tumours (leukaemia, myeloma). The range of alpha particles in biological tissues is very short, less than 0.1 mm, which makes alpha emitters theoretically ideal for treatment of such isolated tumour cells or micro-clusters of malignant cells. Thus, over the last decade, a growing interest for the use of alpha-emitting radionuclides has emerged. Research on targeted alpha therapy (TAT) began years ago in Nantes through cooperation between Subatech, a nuclear physics laboratory, CRCNA, a cancer research centre with a nuclear oncology team and ITU (Karlsruhe, Germany). CD138 was demonstrated as a potential target antigen for Multiple Myeloma, which is a target of huge clinical interest particularly suited for TAT because of the disseminated nature of the disease consisting primarily of isolated cells and small clusters of tumour cells mainly localized in the bone marrow. Thus anti-CD138 antibodies were labelled with bismuth-213 from actinium-225/bismuth-213 generators provided by ITU and used to target multiple myeloma cells. In vitro studies showed cell cycle arrest, synergism with chemotherapy and very little induction

  8. Molecular characterization of alpha 1- and alpha 2-adrenoceptors.

    Science.gov (United States)

    Harrison, J K; Pearson, W R; Lynch, K R

    1991-02-01

    Three 'alpha 1-adrenoceptors' and three 'alpha 2-adrenoceptors' have now been cloned. How closely do these receptors match the native receptors that have been identified pharmacologically? What are the properties of these receptors, and how do they relate to other members of the cationic amine receptor family? Kevin Lynch and his colleagues discuss these questions in this review.

  9. Instrumentation for environmental monitoring. Volume 1. Radiation. Second Edition

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Nero, A.V.; Murphy, D.J.; Graven, R.

    1983-01-01

    This volume describes ionizing radiation and the instruments used for measurement. Units, sources, and effects of radiation are introduced, basic detection methods discussed, and measurement of alpha, beta, gamma and x-radiation described. Sources of anthropogenic radiation are discussed in detail: nuclear power plants, spent-fuel processing, and uranium mining and milling

  10. Disinfection of sewage sludge with gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Melmed, L.N.; Comninos, D.K.

    1979-10-01

    Disinfection of sewage sludge by ionizing radiation, thermoradiation, and radiation combined with oxygenation was investigated in experimentation in Johannesburg, South Africa. Inactivation of Ascaris lumbricoides ova was used as the criterion of disinfection. Experimentation and methodology are explained. Complete inactivation could be obtained when 0.5 kGy radiation was applied at 50..cap alpha..C to a sludge containing 3% solids and when 0.4 kGy radiation was applied at 55..cap alpha..C to a sludge with 20% solids. (1 drawing, 5 graphs, 4 photos, 4 tables)

  11. Alpha wastes treatment

    International Nuclear Information System (INIS)

    Thouvenot, P.

    2000-01-01

    Alter 2004, the alpha wastes issued from the Commissariat a l'Energie Atomique installations will be sent to the CEDRA plant. The aims of this installation are decontamination and wastes storage. Because of recent environmental regulations concerning ozone layer depletion, the use of CFC 113 in the decontamination unit, as previously planned, is impossible. Two alternatives processes are studied: the AVD process and an aqueous process including surfactants. Best formulations for both processes are defined issuing degreasing kinetics. It is observed that a good degreasing efficiency is linked to a good decontamination efficiency. Best results are obtained with the aqueous process. Furthermore, from the point of view of an existing waste treatment unit, the aqueous process turns out to be more suitable than the AVD process. (author)

  12. Neutron-induced alpha radiography

    International Nuclear Information System (INIS)

    Pereira, Marco Antonio Stanojev

    2008-01-01

    A new radiography technique to inspect thin samples was developed. Low energy alpha particles, generated by a boron based screen under thermal neutron irradiation, are used as penetrating radiation. The solid state nuclear track detector CR-39 has been used to register the image. The interaction of the α - particles with the CR-39 gives rise to damages which under an adequate chemical etching became tracks the basic units forming the image. A digital system was developed for data acquisition and data analysis as well as for image processing. The irradiation and etching conditions to obtain the best radiography are 1,3 hours and 25 minutes at 70 deg C respectively. For such conditions samples having 10 μm in thickness can be inspected with a spatial resolution of 32 μm. The use of the digital system has reduced the time spent for data acquisition and data analysis and has improved the radiography image visualization. Furthermore, by using the digital system, it was possible to study several new parameters regarding the tracks which are very important to understand and study the image formation theory in solid state nuclear track detectors, the one used in this thesis. Some radiography images are also shown which demonstrate the potential of the proposed radiography technique. When compared with the other radiography techniques already in use to inspect thin samples, the present one developed in the present paper allows a smaller time to obtain the image, it is not necessary to handle liquid radioactive substances, the detector is insensitive to β, γ, X-ray and visible light. (author)

  13. Hydrogen Balmer alpha intensity distributions and line profiles from multiple scattering theory using realistic geocoronal models

    Science.gov (United States)

    Anderson, D. E., Jr.; Meier, R. R.; Hodges, R. R., Jr.; Tinsley, B. A.

    1987-01-01

    The H Balmer alpha nightglow is investigated by using Monte Carlo models of asymmetric geocoronal atomic hydrogen distributions as input to a radiative transfer model of solar Lyman-beta radiation in the thermosphere and atmosphere. It is shown that it is essential to include multiple scattering of Lyman-beta radiation in the interpretation of Balmer alpha airglow data. Observations of diurnal variation in the Balmer alpha airglow showing slightly greater intensities in the morning relative to evening are consistent with theory. No evidence is found for anything other than a single sinusoidal diurnal variation of exobase density. Dramatic changes in effective temperature derived from the observed Balmer alpha line profiles are expected on the basis of changing illumination conditions in the thermosphere and exosphere as different regions of the sky are scanned.

  14. Actitudes hacia la influencia de la sociedad en la ciencia y la tecnología

    Directory of Open Access Journals (Sweden)

    Manassero Mas, M.ª Antonia

    1999-01-01

    Full Text Available Not available.La filosofía tradicional de la ciencia presenta ésta como un conocimiento objetivo, aislado de influencias externas, mientras que la moderna sociología y epistemología de la ciencia sostienen la influencia de los factores contextuales. Este estudio analiza las actitudes de estudiantes y profesorado sobre la influencia de la sociedad en la ciencia y tecnología mediante una serie de cuestiones referidas a distintos factores sociales, como el gobierno, las empresas e industrias, el ejército, la cultura, los grupos de especial interés o la educación científica y tecnológica del público. Las actitudes obtenidas muestran diferente intensidad y se fundan en distintas razones justificativas, aunque se observa una tendencia a admitir mayoritariamente esta influencia sobre la ciencia cuando se refiere a un factor general, mientras que cuando la influencia de la sociedad se concreta en factores más concretos, las actitudes no concitan tanta unanimidad. Las diferencias entre estudiantes según el grado de exposición a la ciencia no son tan importantes como cabría esperar, y las diferencias de género, cuando se controla la variable anterior son escasas. El análisis comparativo entre profesorado y alumnado muestra más coincidencias que diferencias, y cuando se comparan los estudiantes canadienses con los españoles existen tantas diferencias como coincidencias. Finalmente, se discuten algunas implicaciones para la enseñanza de las ciencias desde una perspectiva de ciencia-tecnología-sociedad (CTS.

  15. Mind Your p's and Alphas.

    Science.gov (United States)

    Stallings, William M.

    In the educational research literature alpha, the a priori level of significance, and p, the a posteriori probability of obtaining a test statistic of at least a certain value when the null hypothesis is true, are often confused. Explanations for this confusion are offered. Paradoxically, alpha retains a prominent place in textbook discussions of…

  16. Summary of Alpha Particle Transport

    Energy Technology Data Exchange (ETDEWEB)

    Medley, S.S.; White, R.B.; Zweben, S.J.

    1998-08-19

    This paper summarizes the talks on alpha particle transport which were presented at the 5th International Atomic Energy Agency's Technical Committee Meeting on "Alpha Particles in Fusion Research" held at the Joint European Torus, England in September 1997.

  17. Proteinaceous alpha-araylase inhibitors

    DEFF Research Database (Denmark)

    Svensson, Birte; Fukuda, Kenji; Nielsen, P.K.

    2004-01-01

    Proteins that inhibit alpha-amylases have been isolated from plants and microorganisms. These inhibitors can have natural roles in the control of endogenous a-amylase activity or in defence against pathogens and pests; certain inhibitors are reported to be antinutritional factors. The alpha-amylase...... inhibitors belong to seven different protein structural families, most of which also contain evolutionary related proteins without inhibitory activity. Two families include bifunctional inhibitors acting both on alpha-amylases and proteases. High-resolution structures are available of target alpha-amylases...... in complex with inhibitors from five families. These structures indicate major diversity but also some similarity in the structural basis of alpha-amylase inhibition. Mutational analysis of the mechanism of inhibition was performed in a few cases and various protein engineering and biotechnological...

  18. A comparison of the alpha and gamma radiolysis of CMPO

    Energy Technology Data Exchange (ETDEWEB)

    Bruce J. Mincher; Stephen P. Mezyk; Gary Groenewold; Gracy Elias

    2011-06-01

    The radiation chemistry of CMPO has been investigated using a combination of irradiation and analytical techniques. The {alpha}-, and {gamma}-irradiation of CMPO resulted in identical degradation rates (G-value, in {mu}mol Gy{sup -1}) for both radiation types, despite the difference in their linear energy transfer (LET). Similarly, variations in {gamma}-ray dose rates did not affect the degradation rate of CMPO. The solvent extraction behavior was different for the two radiation types, however. Gamma-irradiation resulted in steadily increasing distribution ratios for both forward and stripping extractions, with respect to increasing absorbed radiation dose. This was true for samples irradiated as a neat organic solution, or irradiated in contact with the acidic aqueous phase. In contrast, {alpha}-irradiated samples showed a rapid drop in distribution ratios for forward and stripping extractions, followed by essentially constant distribution ratios at higher absorbed doses. These differences in extraction behavior are reconciled by mass spectrometric examination of CMPO decomposition products under the different irradiation sources. Irradiation by {gamma}-rays resulted in the rupture of phosphoryl-methylene bonds with the production of phosphinic acid products. These species are expected to be complexing agents for americium that would result in higher distribution ratios. Irradiation by {alpha}-sources appeared to favor rupture of carbamoyl-methylene bonds with the production of less deleterious acetamide products.

  19. Low-level radiation

    International Nuclear Information System (INIS)

    Myers, D.K.

    1982-05-01

    It is known that the normal incidence of cancer in human populations is increased by exposure to moderately high doses of ionizing radiation. At background radiation levels or at radiation levels which are 100 times greater, the potential health risks are considered to be directly proportional to the total accumulated dose of radiation. Some of the uncertainties associated with this assumption and with the accepted risk estimates have been critically reviewed in this document. The general scientific consensus at present suggests that the accepted risk estimates may exaggerate the actual risk of low levels of sparsely ionizing radiations (beta-, gamma- or X-rays) somewhat but are unlikely to overestimate the actual risks of densely ionizing radiations (fast neutrons, alpha-particles). At the maximum permissible levels of exposure for radiation workers in nuclear power stations, the potential health hazards in terms of life expectancy would be comparable to those encountered in transportation and public utilities or in the construction industry. At the average radiation exposures received by these workers in practice, the potential health hazards are similar to those associated with safe categories of industries. Uranium mining remains a relativly hazardous occupation. In terms of absolute numbers, the genetic hazards, which are less well established, are thought to be smaller than the carcinogenic hazards of radiation when only the first generation is considered but to be of the same order of magnitude as the carcinogenic hazards when the total number of induced genetic disorders is summed over all generations

  20. Fetal dosimetry from natural alpha emitters

    Energy Technology Data Exchange (ETDEWEB)

    Purnell, S.J

    1999-09-01

    The size of marrow cavities in fetal vertebra, rib and sternum was investigated using an image analysis system. The average chord lengths through marrow spaces in the vertebrae were found to increase approximately linearly with gestational age from 140 {mu}m at 20 weeks to 300 {mu}m at 40 weeks. Average chord lengths through marrow spaces in fetal rib and sternum were 330 {mu}m at 35 weeks in both cases. These results can be compared with an average chord length across marrow spaces in adult vertebra of 1172 {mu}m. At natural background UK exposure, activity concentrations of supported {sup 210}Po in fetal bone of 0.075 Bq kg{sup -1} and 0.15 Bq kg{sup -1} at mid- and late gestation respectively were calculated. Monte Carlo simulations modelling the paths of alpha-particles in fetal vertebra gave a total alpha-radiation dose to marrow over the second and third trimesters of 32.0 {+-} 0.8 {mu}Sv with the {sup 210}Po in bone contributing 8.9 {+-} 0.9 {mu}Sv. The dose to primitive haemopoietic stem cells, the target cells for acute lymphoblastic leukaemia, and the survival of these stem cells following a hit by an alpha-particle was investigated, also using Monte Carlo simulations. Alpha-particles emitted from bone and marrow contributed an average dose of 1.9 Gy to stem cells with a nuclear diameter of 3.8 {mu}m. This study has estimated that 1% of babies born each year are born with a mutated primitive haemopoietic stem cell due to in utero irradiation from high LET radiation. That is 7,320 babies compared to an estimated 300 incidences of cALL each year initiated in utero. The probability that a mutated cell will go on to give rise to leukaemia is unknown but it would seem not unlikely that irradiation in utero plays a substantial part in the induction of childhood leukaemia. (author)

  1. Development of a transmission alpha particle dosimetry technique using A549 cells and a Ra-223 source for targeted alpha therapy.

    Science.gov (United States)

    Al Darwish, R; Staudacher, A H; Li, Y; Brown, M P; Bezak, E

    2016-11-01

    In targeted radionuclide therapy, regional tumors are targeted with radionuclides delivering therapeutic radiation doses. Targeted alpha therapy (TAT) is of particular interest due to its ability to deliver alpha particles of high linear energy transfer within the confines of the tumor. However, there is a lack of data related to alpha particle distribution in TAT. These data are required to more accurately estimate the absorbed dose on a cellular level. As a result, there is a need for a dosimeter that can estimate, or better yet determine the absorbed dose deposited by alpha particles in cells. In this study, as an initial step, the authors present a transmission dosimetry design for alpha particles using A549 lung carcinoma cells, an external alpha particle emitting source (radium 223; Ra-223) and a Timepix pixelated semiconductor detector. The dose delivery to the A549 lung carcinoma cell line from a Ra-223 source, considered to be an attractive radionuclide for alpha therapy, was investigated in the current work. A549 cells were either unirradiated (control) or irradiated for 12, 1, 2, or 3 h with alpha particles emitted from a Ra-223 source positioned below a monolayer of A549 cells. The Timepix detector was used to determine the number of transmitted alpha particles passing through the A549 cells and DNA double strand breaks (DSBs) in the form of γ-H2AX foci were examined by fluorescence microscopy. The number of transmitted alpha particles was correlated with the observed DNA DSBs and the delivered radiation dose was estimated. Additionally, the dose deposited was calculated using Monte Carlo code SRIM. Approximately 20% of alpha particles were transmitted and detected by Timepix. The frequency and number of γ-H2AX foci increased significantly following alpha particle irradiation as compared to unirradiated controls. The equivalent dose delivered to A549 cells was estimated to be approximately 0.66, 1.32, 2.53, and 3.96 Gy after 12, 1, 2, and 3 h

  2. ALPHA freezes antiprotons

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Laboratories like CERN can routinely produce many different types of antiparticles. In 1995, the PS210 experiment formed the first antihydrogen atoms and a few years later, in 2002, ATRAP and ATHENA were already able to produce several thousand of them. However, no experiment in the world has succeeded in ‘trapping’ these anti-atoms in order to study them. This is the goal of the ALPHA experiment, which has recently managed to cool down the antiprotons to just a few Kelvin. This represents a major step towards trapping the anti-atom, thus opening a new avenue into the investigation of antimatter properties.   Members of the ALPHA collaboration working on the apparatus in the Antiproton Decelerator experimental hall at CERN. Just like the atom, the anti-atom is neutral. Unlike the atom, the anti-atom is made up of antiprotons (as opposed to protons in the atom) and positrons (as opposed to electrons). In order to thoroughly study the properties of the anti-atoms, scien...

  3. Alpha-1-antitrypsin deficiency.

    Science.gov (United States)

    Bals, Robert

    2010-10-01

    Alpha-1-antitrypsin deficiency (AATD) is a rare genetic disorder associated with the development of liver and lung disease. AAT is a 52-kD glycoprotein, produced mainly by hepatocytes and secreted into the blood. Agglomeration of the AAT-protein in hepatocytes can result in liver disease. Exposure to smoke is the major risk factor for the development of lung disease characterised as early chronic obstructive lung disease (COPD). Diagnosis is based on the analysis of the AAT genotype and phenotype. The measurement of the AAT serum level is useful as screening test. Liver biopsy is not necessary to establish the diagnosis. Therapy for AAT-related liver disease is supportive, a specific therapy is not available. AATD is a rare condition (1:5000-10000) and, as a consequence, data and information on diagnosis and treatment are not easily accessible. This chapter provides a comprehensive overview on AATD, covering basic biology, diagnostic and therapeutic approaches. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Ly(alpha) emission and absorption features in the spectra of galaxies

    Science.gov (United States)

    Chen, W. L.; Neufeld, David A.

    1994-01-01

    The combined effects of interstellar dust absorption and of scattering by hydrogen atoms may give rise to a Ly(alpha) spectral feature of negative equivalent width, as has been observed in several star-forming galaxies. By considering the transfer of Ly(alpha) line radiation and of neighboring stellar continuum radiation within a dusty galaxy, we find that dust absorption has three effects: (1) it reduces the apparent ultraviolet continuum luminosity at all wavelengths; (2) it preferentially decreases the apparent Ly(alpha) line luminosity from H II regions; and (3) it creates an 'attenuation feature' in the continuum spectrum -- centered at the Ly(alpha) rest frequency -- which occurs because the attenuation of the stellar continuum radiation increases as the Ly(alpha) rest frequency is approached, due to the effects of scattering by hydrogen atoms. For plausible values of the galactic dust content and of the disk thickness, these effects can lead to a negative net Ly(alpha) equivalent width, even for galaxies in which the unattenuated spectrum would show a strong Ly(alpha) emission line.

  5. What Powers Lyman alpha Blobs?

    OpenAIRE

    Ao, Y.; Matsuda, Y.; Beelen, A.; Henkel, C.; Cen, R.; De Breuck, C.; Francis, P.; Kovacs, A.; Lagache, G.; Lehnert, M.; Mao, M.; Menten, K. M.; Norris, R.; Omont, A.; Tatemastu, K.

    2015-01-01

    Lyman alpha blobs (LABs) are spatially extended lyman alpha nebulae seen at high redshift. The origin of Lyman alpha emission in the LABs is still unclear and under debate. To study their heating mechanism(s), we present Australia Telescope Compact Array (ATCA) observations of the 20 cm radio emission and Herschel PACS and SPIRE measurements of the far-infrared (FIR) emission towards the four LABs in the protocluster J2143-4423 at z=2.38. Among the four LABs, B6 and B7 are detected in the rad...

  6. Alpha heating in toroidal devices

    Energy Technology Data Exchange (ETDEWEB)

    Miley, G.H.

    1978-01-01

    Ignition (or near-ignition) by alpha heating is a key objective for the achievement of economic fusion reactors. While good confinement of high-energy alphas appears possible in larger reactors, near-term tokamak-type ignition experiments as well as some concepts for small reactors (e.g., the Field-Reversed Mirror or FRM) potentially face marginal situations. Consequently, there is a strong motivation to develop methods to evaluate alpha losses and heating profiles in some detail. Such studies for a TFTR-size tokamak and for a small FRM are described here.

  7. Nano Size Crystals of Geothite, alpha-FeOOH: Synthesis and Thermal Transformation

    Energy Technology Data Exchange (ETDEWEB)

    Christensen,A.; Jensen, T.; Bahl, C.; DiMasi, E.

    2007-01-01

    An aqueous suspension of amorphous iron(III) hydroxide was kept at room temperature (298 K) for 23 years. During this period of time the pH of the liquid phase changed from 4.3 to 2.85, and nano size crystals of goethite, {alpha}-FeOOH crystallized from the amorphous iron(III) hydroxide. Transmission electron microscopy (TEM) investigations, Moessbauer spectra, and powder X-ray diffraction using Co K{alpha} radiation showed that the only iron containing crystalline phase present in the recovered product was {alpha}-FeOOH. The size of these nano particles range from 10 to 100 nm measured by TEM. The thermal decomposition of {alpha}-FeOOH was investigated by time-resolved in situ synchrotron radiation powder X-ray diffraction and the data showed that the sample of {alpha}-FeOOH transformed to {alpha}-Fe{sub 2}O{sub 3} in the temperature range 444--584 K. A quantitative phase analysis shows the increase in scattered X-ray intensity from {alpha}-Fe{sub 2}O{sub 3} to follow the decrease of intensity from {alpha}-FeOOH in agreement with the topotactic phase transition.

  8. Chromosomal aberrations induced by alpha particles

    International Nuclear Information System (INIS)

    Guerrero C, C.; Brena V, M.

    2005-01-01

    The chromosomal aberrations produced by the ionizing radiation are commonly used when it is necessary to establish the exposure dose of an individual, it is a study that is used like complement of the traditional physical systems and its application is only in cases in that there is doubt about what indicates the conventional dosimetry. The biological dosimetry is based on the frequency of aberrations in the chromosomes of the lymphocytes of the individual in study and the dose is calculated taking like reference to the dose-response curves previously generated In vitro. A case of apparent over-exposure to alpha particles to which is practiced analysis of chromosomal aberrations to settle down if in fact there was exposure and as much as possible, to determine the presumed dose is presented. (Author)

  9. Benchmarks for targeted alpha therapy for cancer

    International Nuclear Information System (INIS)

    Allen, J.B.

    2011-01-01

    Full text: Targeted alpha therapy (TAT) needs to achieve certain benchmarks if t is to find its way into the clinic. This paper reviews the status of benchmarks for dose normalisation, microdosimetry, response of micrometastases to therapy, maximum tolerance doses and adequate supplies of alpha emitting radioisotopes. In comparing dose effect for different alpha immunoconjugates (IC), patients and diseases, it is appropriate to normalise dose according to specific factors that affect the efficacy of the treatment. Body weight and body surface area are two commonly used criteria. However, more advanced criteria are required, such as the volume of distribution. Alpha dosimetry presents a special challenge in clinical trials. Monte Carlo calculations can be used to determine specific energies, but these need validation. This problem could be resolved with micronuclei biological dosimetry and mutagenesis studies of radiation Jam age. While macroscopic disease can be monitored, the impact of therapy on subclinical microscopic disease is a real problem. Magnetic cell separation of cancer cells in the blood with magnetic microspheres coated with the targeting monoclonal antibody could provide the response data. Alpha therapy needs first to establish maximum tolerance doses for practical acceptance. This has been determined with 213Bi-IC for acute myelogenous leukaemia at ∼ I mCi/kg. The maximum tolerance dose has not yet been established for metastatic melanoma, but the efficacious dose for some melanomas is less than 0.3 mCi/kg and for intra-cavity therapy of GBM it is ∼ 0.14 mCi/kg for 211 At-Ie. In the case of Ra-223 for bone cancer, the emission of four alphas with a total energy of 27 MeV results in very high cytotoxicity and an effective dose of only ∼ 5 μCi/kg. The limited supplies of Ac-225 available after separation from Th-229 are adequate for clinical trials. However, should TAT become a clinical procedure, then new supplies must be found. Accelerator

  10. Evaluation of charge coupled devices as alpha particle detectors

    International Nuclear Information System (INIS)

    Pace, R.; Haskard, M.; Watts, S.; Holmes-Siedle, A.; Solanky, M.

    1996-01-01

    The ability of the Charge Coupled Device (CCD) to provide spectroscopic and flux information for highly ionising radiation has been investigated. CCDs and related imaging chips are becoming increasingly affordable. In addition advances in technology are producing smaller and better devices. Since imaging chips are based on some variation of the pn-diode structure it is expected and known that they are sensitive to ionising radiation as well as light. Indeed specially designed CCDs are able to be used to image X-rays. This paper reports on the response of CCDs to alpha particles. (author)

  11. La danza y su influencia en la percepción de plenitud y bienestar psicoemocional.

    OpenAIRE

    Rengifo Rodríguez, Lorelcris; Carrero Planes, Virginia

    2016-01-01

    Introducción: Desde los resultados obtenidos en diversas investigaciones que han identificado la influencia del trabajo corporal sobre la inteligencia emocional y otras variables psicológicas, se derivó el interés por descubrir los efectos o beneficios de la danza sobre las habilidades emocionales u otros procesos psicosociales asociados al bienestar y plenitud. El trabajo que se presenta tiene como objetivo explorar la vivencia de personas que practican danza, de manera profes...

  12. Influencia de la adición del filler calizo sobre el fraguado del cemento

    Directory of Open Access Journals (Sweden)

    Menéndez, Ignacio

    1993-09-01

    Full Text Available The present paper deals about the infuence that addition of calcareous "filler" has on the set of portland cement which rates are from 0 up to 50% of filler.

    En el presente artículo se estudia la influencia que la adición de "filler" calizo ejerce sobre el fraguado del cemento portland, al que se le añaden porcentajes desde O al 50% en filler.

  13. La influencia portuguesa en el arte autóctono del Golfo de Guinea

    OpenAIRE

    Sanz Serrano, María Jesús

    2010-01-01

    Atrio: Revista de historia del arte nº 15-16 (2010), p. 187-198 Los viajes de exploración, intercambios comerciales y colonización portugueses desde el siglo XV en las costas africanas del Golfo de Guinea supusieron la influencia de los nuevos motivos representativos portugueses en las creaciones artísticas de las culturas africanas indígenas de la zona. Versión del editor

  14. Quartz luminescence response to a mixed alpha-beta field: Investigations on Romanian loess

    International Nuclear Information System (INIS)

    Constantin, Daniela; Jain, Mayank; Murray, Andrew S.; Buylaert, Jan-Pieter; Timar-Gabor, Alida

    2015-01-01

    Previous SAR-OSL dating studies using quartz extracted from Romanian and Serbian loess samples report SAR-OSL dose–response curves on fine grained (4–11 μm) quartz that grow to much higher doses compared to those of coarse-grained (63–90, 90–125, 125–180 μm) quartz. Furthermore, quartz SAR-OSL laboratory dose response curves do not reflect the growth of the OSL signal in nature. A main difference in coarse- and fine-grained quartz dating lies in the alpha irradiation history, but the effect of mixed alpha-beta fields has so far received little attention. In the present study we investigate whether the alpha dose experienced by fine grains over geological cycles of irradiation and bleaching may have an effect on the saturation characteristics of the laboratory dose response. By applying time resolved optically stimulated luminescence we confirm that the OSL signals induced in quartz by alpha and beta radiation follow the same recombination path. We also show that a mixed alpha-beta dose response reproduces the beta dose response only up to about 800 Gy. Assuming an a-value of 0.04 we have shown that laboratory alpha and beta dose response curves overlap up to effective alpha doses of ∼50 Gy. Based on these results, we conclude that exposure of fine grains to alpha radiation during burial and transport cycles prior to deposition, as well exposure to the mixed radiation field experienced during burial are not responsible for the age discrepancies previously reported on fine and coarse grained quartz extracted from Romanian and Serbian loess. - Highlights: • Prior alpha irradiation history does not influence the laboratory beta growth curves. • Alpha and beta induced photon emissions in quartz follow the same recombination path. • Laboratory alpha and beta growth curves overlap up to total alpha doses of ∼1250 Gy. • Mixed alpha-beta growth curves reproduce the beta dose response curves up to ∼800 Gy. • Mixed radiation field is not

  15. Classification of alpha 1-adrenoceptor subtypes

    NARCIS (Netherlands)

    Michel, M. C.; Kenny, B.; Schwinn, D. A.

    1995-01-01

    Two alpha 1-adrenoceptor subtypes (alpha 1A and alpha 1B) have been detected in various tissues by pharmacological techniques, and three distinct cDNAs encoding alpha 1-adrenoceptor subtypes have been cloned. The profile of an increasing number of subtype-selective compounds at cloned and endogenous

  16. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1975-01-01

    Physical and radiological terms, quantities, and units. Basic principles of radiation protection (ICRP, IAEA, EURATOM, FRG). Biological effects of ionizing radiation. Objectives of practical radiation protection. (HP) [de

  17. Triplication of alpha-globin genes is responsible for unusual alpha 113Leu/alpha 113His-globin chain ratios in sheep.

    Science.gov (United States)

    Vestri, R; Masina, P; Rando, A; Testa, A; Di Gregorio, P

    1987-10-01

    By investigations at the DNA and protein level, it has been shown that in sheep a previously detected, presumed quantitative allele of the II alpha 113His gene, displaying a reduced efficiency (called the II alpha 113His decreases gene), is carried by a chromosome bearing three alpha-globin loci. In particular, five sheep having an alpha 113Leu/alpha 113His-chain ratio of about 13:1 (13:1 phenotype) possessed the -I alpha 113Leu-II alpha 113Leu-/-I alpha 113Leu-II alpha 113Leu-III alpha 113His decreases genotype. One sheep showing a alpha 113Leu/alpha 113His-chain ratio of about 3:1 (3:1 phenotype) had the -I alpha 113Leu-II alpha 113His-/-I alpha 113Leu-II alpha 113Leu-III alpha 113His decreases genotype, while one sheep having a chain ratio of about 6:1 (6:1 phenotype) carried the -I alpha 113Leu-II alpha 113Leu-II alpha 113His decreases-/-I alpha 113Leu-II alpha 113Leu-III alpha 113His decreases genotype. Nineteen sheep, displaying the common phenotypes, all possessed the alpha alpha/alpha alpha gene arrangement. Furthermore, the possible location of the gene with reduced efficiency and the expression of the three genes in the triple alpha-globin loci chromosome are discussed.

  18. Measuring radon levels at high exposures with alpha-track detectors. Calibration and analysis

    International Nuclear Information System (INIS)

    Aanestad, Katrine; Roennqvist, Tryggve; Jensen, Camilla Lunder

    2007-01-01

    This report presents the TADTAC method - a track area dependent total area counting method, for measuring radon levels at high exposures with alpha-track detectors. Normally radon levels are measured by counting individual tracks. The TADTAC method is developed by Gammadata Maaleteknik AB and implemented at The Norwegian Radiation Protection Authority. Alpha-track detectors used for testing and calibrating the method where exposed at Physikalisch-Technische Bundesanstalt (PTB) in Germany. (author) (tk)

  19. Dose response of alanine and methyl alanine towards gamma and in-situ alpha irradiation

    International Nuclear Information System (INIS)

    Mohapatra, M.; Rajeswari, B.; Bhide, M.K.; Rane, Vinayak; Kadam, R.M.

    2017-01-01

    In situ alpha and external gamma dose response of two ESR (electron spin resonance) dosimetric materials namely alanine and methyl alanine were investigated. It was observed that alanine dosimeter had a better dose response in comparison to methyl alanine for the in-situ alpha irradiation by using 239 Pu powder. On the other hand, in case of gamma radiation, methyl alanine was found to have the sensitivity as twice that of alanine. (author)

  20. Contribution to the study of the alpha-alpha interaction

    International Nuclear Information System (INIS)

    Darriulat, Pierre

    1965-01-01

    The new variable energy cyclotron at Berkeley that can accelerate an alpha beam up to an energy of 130 MeV and the mass production of lithium diffused junctions have enabled us to perform 2 series of measurement, in the first one we use alpha beams with an energy ranging between 50 and 120 MeV to study alpha-alpha forces in the second one we use the flexibility of the variable energy cyclotron the resonances around 40 MeV, region that can not yet be reached by tandem accelerators. This work is divided into 6 chapters. The first chapter is dedicated to the formalism of partial wave analysis and the theory of the compound nucleus. In the second chapter the author presents the 88 cyclotron at Berkeley and the diffusion chamber, the alpha detectors are lithium diffused junctions made of silicon. The third chapter deals with the experimental methods used and the issue of the reduction of the volume of data. In the fourth chapter the results obtained in the upper part of the energy range are described in terms of complex shifts that allow the description of the α-α interaction at high energy. The very low impact parameter has enabled us to find 2 new components (l=6 and l=8) of the rotational spectrum and to define a more accurate phenomenological potential. The fifth chapter is dedicated to the narrow resonances we have found between 12 and 27 MeV. We present in the last chapter a calculation of the binding energy of C 12 in which we have considered the 12 C nucleus as formed by 3 alpha particles interacting with each other through the phenomenological potential defined above

  1. Determination of alpha-Tocopherol (vitamin E) in irradiated garlic by high performance liquid chromatography (HPLC); Determinacao de alpha-tocoferol em alho irradiado utilizando cromatografia liquida de alta frequencia (CLAE)

    Energy Technology Data Exchange (ETDEWEB)

    Rios, Magda Dias Goncalves; Penteado, Marilene de Vuono Camargo [Sao Paulo Univ., SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Alimentos e Nutricao Experimental]. E-mail: riosmagda@hotmail.com

    2003-02-01

    The effects of {sup 60}Co ionizing radiations in doses of 0, 75, 100, 150, 200 and 250Gy on garlic, upon the {alpha}-tocopherol concentration were studied. The {alpha}-tocopherol contents were established by high performance liquid chromatography (HPLC), after direct hexane extraction from the garlic samples. The {alpha}-tocopherol was determined through normal phase column, and mobile phase was composed by hexane: iso-propyl alcohol (99:01 v/v), with 2mL/min flow rate and fluorescence detector. It is statistically shown that an irradiation dose of up to 150 Gy does not affect the garlic {alpha}-tocopherol content. (author)

  2. Workshop on Precision Measurements of $\\alpha_s$

    Energy Technology Data Exchange (ETDEWEB)

    Bethke, Siegfried; /Munich, Max Planck Inst.; Hoang, Andre H.; /Vienna U.; Kluth, Stefan; /Munich, Max Planck Inst.; Schieck, Jochen; /Munich U.; Stewart, Iain W.; Aoki, S.; Beneke, M.; Bethke, S.; Blumlein, J.; Brambilla, N.; Brodsky, S.; /MIT, LNS

    2011-10-01

    These are the proceedings of the Workshop on Precision Measurements of {alpha}{sub s} held at the Max-Planck-Institute for Physics, Munich, February 9-11, 2011. The workshop explored in depth the determination of {alpha}{sub s}(m{sub Z}) in the {ovr MS} scheme from the key categories where high precision measurements are currently being made, including DIS and global PDF fits, {tau}-decays, electro-weak precision observables and Z-decays, event-shapes, and lattice QCD. These proceedings contain a short summary contribution from the speakers, as well as the lists of authors, conveners, participants, and talks.

  3. Alpha particles induce expression of immunogenic markers on tumour cells

    International Nuclear Information System (INIS)

    Gorin, J.B.; Gouard, S.; Cherel, M.; Davodeau, F.; Gaschet, J.; Morgenstern, A.; Bruchertseifer, F.

    2013-01-01

    The full text of the publication follows. Radioimmunotherapy (RIT) is an approach aiming at targeting the radioelements to tumours, usually through the use of antibodies specific for tumour antigens. The radiations emitted by the radioelements then induce direct killing of the targeted cells as well as indirect killing through bystander effect. Interestingly, it has been shown that ionizing radiations, in some settings of external radiotherapy, can foster an immune response directed against tumour cells. Our research team is dedicated to the development of alpha RIT, i.e RIT using alpha particle emitters, we therefore decided to study the effects of such particles on tumour cells in regards to their immunogenicity. First, we studied the effects of bismuth 213, an alpha emitter, on cellular death and autophagy in six different tumour cell lines. Then, we measured the expression of 'danger' signals and MHC molecules at the cell surface to determine whether irradiation with 213 Bi could cause the tumour cells to be recognized by the immune system. Finally a co-culture of dendritic cells with irradiated tumour cells was performed to test whether it would induce dendritic cells to mature. No apoptosis was detected within 48 hours after irradiation in any cell line, however half of them exhibited signs of autophagy. No increase in membrane expression of 'danger' signals was observed after treatment with 213 Bi, but we showed an increase in expression of MHC class I and II for some cell lines. Moreover, the co-culture experiment indicated that the immunogenicity of a human adenocarcinoma cell line (LS 174T) was enhanced in vitro after irradiation with alpha rays. These preliminary data suggest that alpha particles could be of interest in raising an immune response associated to RIT. (authors)

  4. Estimation of background radiation at Rivers State University of ...

    African Journals Online (AJOL)

    Background radiation from the use of photocopies, computers and other electronic devices around River State University of Science and Technology was measured using a specialize digital, radiation meter type, radalert - 50, which is optimized to detect radiations like alpha, beta, gamma and x-rays. Measurements were ...

  5. Radiation enteritis

    Science.gov (United States)

    Radiation enteropathy; Radiation-induced small bowel injury; Post-radiation enteritis ... Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells. The therapy ...

  6. Measurement of natural radioactivity in chemical fertilizer and agricultural soil: evidence of high alpha activity.

    Science.gov (United States)

    Ghosh, Dipak; Deb, Argha; Bera, Sukumar; Sengupta, Rosalima; Patra, Kanchan Kumar

    2008-02-01

    People are exposed to ionizing radiation from the radionuclides that are present in different types of natural sources, of which phosphate fertilizer is one of the most important sources. Radionuclides in phosphate fertilizer belonging to 232Th and 238U series as well as radioisotope of potassium (40K) are the major contributors of outdoor terrestrial natural radiation. The study of alpha activity in fertilizers, which is the first ever in West Bengal, has been performed in order to determine the effect of the use of phosphate fertilizers on human health. The data have been compared with the alpha activity of different types of chemical fertilizers. The measurement of alpha activity in surface soil samples collected from the cultivated land was also performed. The sampling sites were randomly selected in the cultivated land in the Midnapore district, which is the largest district in West Bengal. The phosphate fertilizer is widely used for large agricultural production, mainly potatoes. The alpha activities have been measured using solid-state nuclear track detectors (SSNTD), a very sensitive detector for alpha particles. The results show that alpha activity of those fertilizer and soil samples varies from 141 Bq/kg to 2,589 Bq/kg and from 109 Bq/kg to 660 Bq/kg, respectively. These results were used to estimate environmental radiation exposure on human health contributed by the direct application of fertilizers.

  7. Simulation of radiation damage in zircon

    Energy Technology Data Exchange (ETDEWEB)

    Weber, W.J.; Maupin, G.D.

    1988-05-01

    Radiation damage in natural zircon minerals due to alpha decay over geologic time has been simulated in laboratory studies extending over 5.5 years using Pu-doped synthetic zircon. These studies confirm for the first time that laboratory testing of actinide-doped materials can accurately predict the radiation-damage behavior of radioactive waste forms over geologic time and also provide new insights into interpretation of radiation damage in natural minerals.

  8. Simulation of radiation damage in zircon

    Energy Technology Data Exchange (ETDEWEB)

    Weber, W.J.; Maupin, G.D.

    1987-06-01

    Radiation damage in natural zircon minerals due to alpha decay has been simulated in laboratory studies using Pu-doped synthetic zircon. These studies confirm that laboratory testing of actinide-doped materials can accurately predict the radiation-damage behavior of radioactive waste forms over geologic time, and also provide new insights into interpretation of radiation damage in natural minerals. 15 refs., 4 figs., 2 tabs.

  9. Radiation biology

    International Nuclear Information System (INIS)

    Neumeister, K.

    1977-01-01

    This chapter is included in a textbook which is primarily intended for medical students. The following topics are dealt with: radiation effects on molecules; chemical and biochemical radiation effects; modification of radiation effects and radiosensitivity; radiation-induced pathomorphological and pathophysiological effects in organs and organ systems; radiation syndrome; radiation effects in embryos and fetuses; genetic radiation effects; carcinogenesis and leukemogenesis after irradiation; and radiation effects after intake of radionuclides

  10. RADIATION AND EFFECTS ON HUMAN HEALTH

    Directory of Open Access Journals (Sweden)

    Hakan YAREN

    2005-08-01

    Full Text Available In modern world, living without radiation is impossible. Radiation is defined as ?energy transmitted through space as waves or particles? and also determined as ?particles or waves emitted from the nucleus of unstable radioactive atoms to become stable? Mainly two types of radiation are exist; ionising radiation and non-ionising radiation. Ionising radiation is consist of alpha, beta particules, neutrons, x rays and gamma rays. Ionising radiation which can be measured by ion chambers, geiger-Mueller detectors, Scintillation Counters, fluorescent counters etc. Has harmfull effects on human health in levels of molecular, cellular, tissue, organs and organ systems. These harmfull effects can also be named somatic and genetic. One of the most encountered problem is ?Acute Radiation Syndrom? which has three sub syndroms called haematopoetic syndrom, gastrointestinal syndrom and neurovascular syndrom. Exposure time, distance and armorisation are the key elements of protection from radiation. [TAF Prev Med Bull 2005; 4(4.000: 199-208

  11. Conditioning of alpha bearing wastes

    International Nuclear Information System (INIS)

    1991-01-01

    Alpha bearing wastes are generated during the reprocessing of spent fuel, mixed oxide fuel fabrication, decommissioning and other activities. The safe and effective management of these wastes is of particular importance owing to the radiotoxicity and long lived characteristics of certain transuranic (TRU) elements. The management of alpha bearing wastes involves a number of stages which include collection, characterization, segregation, treatment, conditioning, transport, storage and disposal. This report describes the currently available matrices and technologies for the conditioning of alpha wastes and relates them to their compatibility with the other stages of the waste management process. The selection of a specific immobilization process is dependent on the waste treatment state and the subsequent handling, transport, storage and disposal requirements. The overall objectives of immobilization are similar for all waste producers and processors, which are to produce: (a) Waste forms with sufficient mechanical, physical and chemical stability to satisfy all stages of handling, transport and storage (referred to as the short term requirements), and (b) Waste forms which will satisfy disposal requirements and inhibit the release of radionuclides to the biosphere (referred to as the long term requirements). Cement and bitumen processes have already been successfully applied to alpha waste conditioning on the industrial scale in many of the IAEA Member States. Cement systems based on BFS and pozzolanic cements have emerged as the principal encapsulation matrices for the full range of alpha bearing wastes. Alternative technologies, such as polymers and ceramics, are being developed for specific waste streams but are unlikely to meet widespread application owing to cost and process complexity. The merits of alpha waste conditioning are improved performance in transport, storage and disposal combined with enhanced public perception of waste management operations. These

  12. Radiation physics, biophysics, and radiation biology

    International Nuclear Information System (INIS)

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood ''biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons

  13. Radiation physics, biophysics, and radiation biology

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  14. Evaluate an impact of incident alpha particle and gamma ray on human blood components: A comparison study

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, Asaad H.; Yaba, Sardar P.; Ismail, Haider J. [Medical Physics Research Group, Physics Department, Education College, Salahaddin University-Erbil, Iraqi Kurdistan (Iraq)

    2015-07-01

    An impact of alpha and gamma irradiation on human blood components have been evaluated and compared for healthy blood samples (male and females). Irradiation dose and time of irradiation calibrated and considered as a main comparison factors. Density of blood components measured for each in vitro irradiation before and after irradiation for males and females. Survey radiation dosimeter (Inspector Exp) and nuclear track detectors type CR-39 used to evaluate exposure dose rate and incident density of alpha particles, respectively. Experiment results verified that the irradiation of blood makes ionizing of blood components, either alpha or gamma irradiation dose, and the impacts of ionizing radiation were relativity for WBC, RBC, and PLT. Limited irradiation doses of 1-5 μSv/hr considered as a low radiation dose of alpha and gamma radiation sources ({sup 226}Ra, and {sup 137}Cs). Density of alpha particles accumulated on the blood surface was 34 (alpha particle/cm{sup 2}) for selected dose of incident alpha particle. Optimum value of irradiation dose and time of irradiation were 5 μSv/hr and 4 second for males and females. On the other hands, the values of irradiation dose and time of irradiation were 2.1 μSv/hr and 2 second for males and females for gamma irradiation. Thus, present results demonstrated that densities of RBC and WBC cells are capable of inducing reproduction in vitro for both type of irradiation. (authors)

  15. La polémica influencia de Adolfo Posada en el pensamiento de los catedráticos de derecho de la generación del 900

    Directory of Open Access Journals (Sweden)

    Raquel García Bouzas

    2014-10-01

    Full Text Available Contenido: Las razones de la influencia de Posada entre los juristas rioplatenses. Un particular enfoque del krausismo. Receptividad y difusión de su pensamiento. Concepción organicista del estado. El sufragio como un deber.Valoración de su influencia en nuestra historia intelectual

  16. Improved Alpha Testing Using Hashed Sampling.

    Science.gov (United States)

    Wyman, Chris; McGuire, Morgan

    2017-08-14

    We further describe and analyze the idea of hashed alpha testing from Wyman and McGuire [1], which builds on stochastic alpha testing and simplifies stochastic transparency. Typically, alpha testing provides a simple mechanism to mask out complex silhouettes using simple proxy geometry with applied alpha textures. While widely used, alpha testing has a long-standing problem: geometry can disappear entirely as alpha mapped polygons recede with distance. As foveated rendering for virtual reality spreads, this problem worsens as peripheral minification and prefiltering introduce this problem on nearby objects.

  17. Response of commercial photodiodes for application in alpha spectrometry

    International Nuclear Information System (INIS)

    Ferreira Filho, Alfredo Lopes

    1998-06-01

    The use of semiconductor detector for ionizing radiations spectrometry and dosimetry has been growing in the last years due to its characteristics of fast response, good efficiency for unit of volume and excellent resolution. Since the working principle of a semiconductor detector is identical to that of the semiconductor junctions of commercial electronic devices, a study was carried out on the PIN-photodiodes response, aiming at set up an alpha spectrometry system of low cost and easy acquisition. The tested components have the following characteristics: active area varying between 13.2 and 25 mm 2 , window of thickness equal or lower than 57 mg/cm 2 , depletion area with depth ranging from 10 to 300 μm and junction capacitance of 16 to 20 pF.Am-241, Cm-244, U-233 and Np-237 alpha sources produced by electrodeposition were used to evaluate the response of the devices as a function of the radiation energy. The results have shown a linear response of the photodiodes with the incident alpha particle energy. The resolution varied from 1.6% to 0.45% and the better detection efficiency found was about 7.2. The low cost of the photodiodes and the excellent results obtained at room temperature make such components very attractive for teaching purposes for environmental monitoring. (author)

  18. TARCC: Targeting Alpha-Radionuclide to Combat Cancer

    International Nuclear Information System (INIS)

    Barbet, J.; Cherel, M.; Maecke, H.; Senekowitsch-Schmidtke, R.; Meyer, G.; Forssell-Aronsson, E.; Gmeiner Stopar, T.; Montavon, G.; Bruchertseifer, F.; Lambert, B.; Joseph-Mathieu, P.

    2009-01-01

    Cancer is a human health problem with many unmet needs. Today treatments mainly rely on surgery, external beam radiation and chemotherapy to remove or destroy bulky tumours. However, they cannot permanently treat all cancer and relapse occurs in up to 50% of the patients' population. Targeted radionuclide therapy (TRT) offers an alternative with unlikely cross-resistance with established therapies to treat small size tumours (residual disease, micro metastases). In contrast to beta radionuclides, alpha-emitting radionuclides seem particularly promising to selectively destroy disseminated cancer cells, due to their decay characteristics. The challenge remains to deliver the radioactive atoms fast and efficiently enough and to find the right balance between toxicity and anti-tumour effect. The TARCC project proposes a concerted and multidisciplinary action plan to develop targeted alpha-radionuclide therapy to: - Improve the access to the most promising alpha-emitting radionuclides. - Test in appropriate preclinical models new radiolabelling methods and new biological vectors to target the radionuclides to cancer cells in vivo. - Compare the results obtained with the different vectors (antibodies, peptides, amino- acids or nanocolloids) in different preclinical tumour models. - Evaluate short-term and long-term treatment toxicity and dosimetry at both macroscopic and microscopic levels. It is expected that this network approach will make it possible to select several candidates for future preclinical and clinical developments and to define the most promising settings for targeted alpha-radionuclide therapy in terms of vector properties and modes of administration. (author)

  19. The alpha effectiveness of the dating ESR signal in barite

    International Nuclear Information System (INIS)

    Toyoda, Shin; Sato, Fumihiro; Nishido, Hirotsugu; Kayama, Masahiro; Ishibashi, Jun-Ichiro

    2012-01-01

    The alpha effectiveness was investigated for an ESR signal due to SO 3 − in barite by comparing the dose responses of the signal for gamma irradiation and for He ion implantation with an energy of 4 MeV. The value was obtained to be 0.043 ± 0.018 for samples from Morocco and to be 0.0089 ± 0.0006 for Kanehira Mine. The dose response for He ion implantation for the latter sample better fits to a correlation line but the signal shape changes with gamma ray dose, indicating contribution from an unknown radiation sensitive signal, while the former sample shows the same signal shapes. A value of 0.043 ± 0.018 is adopted as the alpha effectiveness of SO 3 − signal in barite, which is used for ESR dating of submarine hydrothermal activity. - Highlights: ► The alpha effectiveness is one of the essential factors in ESR dating. ► The alpha effectiveness value was determined for barite. ► The dose responses for gamma and for He ion implantation were compared. ► A sample shows signal shape change by gamma ray irradiation.

  20. Natural radiation dose to Gammarus

    International Nuclear Information System (INIS)

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

    1975-01-01

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

  1. Induction of endogenous tumor necrosis factor-alpha: suppression of centrally stimulated gastric motility.

    Science.gov (United States)

    Hermann, G E; Tovar, C A; Rogers, R C

    1999-01-01

    Gastric stasis is frequently seen in conjunction with critical infectious illness, chronic inflammatory disorders, radiation sickness, and carcinogenesis. These conditions are associated with elevated circulating levels of the cytokine tumor necrosis factor-alpha (TNF-alpha). The present studies examined the relationship between endogenously produced TNF-alpha and the central neural mechanisms that augment gastric motility. Systemic lipopolysaccharide (LPS) was employed to induce TNF-alpha production in thiobutabarbital-anesthetized rats. Sixty minutes after intravenous LPS injection, gastric motility could not be stimulated by a potent centrally acting gastrokinetic stimulant, thyrotropin-releasing hormone (TRH). This failure to elicit gastric motility via central mechanisms coincided with high circulating levels of TNF-alpha. However, intravenous injections of bethanecol, a peripherally acting cholinergic agonist with direct gastrokinetic effects, were still able to elicit normal increases in gastric motility in the presence of TNF-alpha and LPS. Therefore, the inability to stimulate gastric motility via central TRH could not be attributed to the direct inhibitory effects of either LPS or TNF-alpha on the stomach. If the production of endogenous TNF-alpha was suppressed via the use of urethan as the anesthetic agent, then intravenous injections of LPS were no longer effective in suppressing gastric motility. Thus these effects on gastric motility are not directly attributable to LPS nor are they due to direct effects on the gastric smooth muscle. Our previous study demonstrated that microinjection of femtomole quantities of TNF-alpha in the brain stem dorsal vagal complex (DVC) can modulate gastric motility. This central TNF-alpha effect on gastric motility was dose dependent and required an intact vagal efferent pathway. The results from these two studies suggest that systemically produced TNF-alpha may gain access to the DVC to modulate gastric function.

  2. ALPHA,·ANTITRYPSIN DEFICIENCY*

    African Journals Online (AJOL)

    1971-02-06

    Feb 6, 1971 ... Lieberman," in fact, found that 15·2% of 66 patients hospitalized with pulmonary emphysema had heterozygous alpha,-antitrypsin deficiency. The over-all incidence of the deficiency was 25'8% in this group. Of patients under the age of 50 years, 47·8% had deficient levels. If such observations are confirmed ...

  3. Alpha sources deposit by sublimation

    International Nuclear Information System (INIS)

    Amoudry, F.; Eloy, J.F.

    1983-09-01

    We studied and realized a device able to perform some very thin substracts used for alpha spectrometry measurements. Sources are prepared by sublimation of the sample in a vacuum container. The energy required for this sublimation is furnished by a laser beam [fr

  4. Luminiscent emission of molecular levels excited by ionizant radiations

    International Nuclear Information System (INIS)

    Ortiz Ramis, M.

    1977-01-01

    The emission spectra and the time dependence of scintillations produced by alpha particles, gamma rays and ultraviolet light in some organic compounds crystals and liquids solutions normally used as radiation detectors has been studied. (author) [es

  5. Alpha-emitting radionuclides in cigarette tobacco

    International Nuclear Information System (INIS)

    Neton, James W.; Ibrahim, Shawki Amin

    1978-01-01

    As part of general studies of the concentration of 239/240 Pu, 238 Pu and 228,230,232 Th in the tissues of non-occupationally exposed individuals, it became evident that there was little or no information on their content in cigarette tobacco. To better understand this possible route of intake and its potential for lung exposure we have measured these nuclides in tobacco samples, from the U.S. Department of Agriculture (USDA), which have a well-known growing history, and in brand name cigarettes purchased commercially. The concentration of 239/240 Pu in both USDA and brand name tobacco has a range of 0.4-0.7 pCi/kg of tobacco while the 238 Pu concentration was ≤ 0.05 pCi/kg. The 228 Th concentration for USDA tobacco was 200 pCi/kg tobacco while the 232 Th was only 14 pCi/kg. The high 228/232 Th ratio may result from a lower uptake of 232 Th compared to that of 228 Ra. By comparing the concentration of these measured nuclides to other alpha emitters in tobacco that have been reported in the literature, i.e. 210 Po (400 pCi/kg) and 226 Ra (150 pCi/kg), it is apparent that 228 Th represents a significant fraction of the total alpha activity. It is also evident there is a much greater potential for exposure of the lung to radiation from 228 Th than from 239/240 Pu as a result of cigarette smoking. (author)

  6. Three-Dimensional Conformal Radiotherapy in Prostate Cancer Patients: Rise in Interleukin 6 (IL-6) but not IL-2, IL-4, IL-5, Tumor Necrosis Factor-{alpha}, MIP-1-{alpha}, and LIF Levels

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Lopes, Carlos [Universidade do Vale do Paraiba, Centro de Oncologia Radioterapica do Vale do Paraiba, Universidade do Vale do Paraiba Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Sao Jose dos Campos, Sao Paulo (Brazil); Callera, Fernando, E-mail: fcallera@gmail.com [Centro de Hematologia Onco-hematologia e Transplantes de Medula Ossea do Vale do Paraiba, Sao Paulo (Brazil)

    2012-03-15

    Purpose: To investigate the effect of radiotherapy (RT) on serum levels of interleukin-2 (IL-2), IL-4, IL-5, IL-6, tumor necrosis factor alpha (TNF-{alpha}), macrophage inflammatory protein-1-alpha (MIP-1-{alpha}) and leukemia inhibitory factor (LIF) in patients with prostate cancer. Methods and Materials: Forty eight patients with prostate cancer received three-dimensional conformal blocking radiation therapy with a linear accelerator. IL-2, IL-4, IL-5, IL-6, TNF-{alpha}, MIP-1-{alpha}, and LIF levels were measured by the related immunoassay kit 1 day before the beginning of RT and during RT at days 15 and 30. Results: The mean IL-2 values were elevated before and during the RT in contrast with those of IL-4, IL-5, IL-6, TNF-{alpha}, MIP-1-{alpha}, and LIF, which were within the normal range under the same conditions. Regarding markers IL-2, IL-4, IL-5, TNF-{alpha}, MIP-1-{alpha}, and LIF, comparisons among the three groups (before treatment and 15 and 30 days during RT) did not show significant differences. Although values were within the normal range, there was a significant rise in IL-6 levels at day 15 of RT (p = 0.0049) and a decline at day 30 to levels that were similar to those observed before RT. Conclusions: IL-6 appeared to peak after 15 days of RT before returning to pre-RT levels. In contrast, IL-2, IL-4, IL-5, TNF-{alpha}, MIP-1-{alpha}, and LIF levels were not sensitive to irradiation. The increased levels of IL-6 following RT without the concurrent elevation of other cytokines involved in the acute phase reaction did not suggest a classical inflammatory response to radiation exposure. Further studies should be designed to elucidate the role of IL-6 levels in patients with prostate cancer treated with RT.

  7. La influencia de Gregorio Magno en Alberto Magno: Super Dionysii Mysticam Theologiam et Epistulas

    Directory of Open Access Journals (Sweden)

    Anneliese Meis

    2010-01-01

    Full Text Available Si bien la influencia de Gregorio Magno fue decisiva para la historia del pensamiento teológico práctico en la Edad Media, siendo Gregorio el autor más citado en la STh de Tomás de Aquino después de Agustín, su influencia sobre Alberto Magno no ha sido estudiada recientemente. En efecto, Alberto Magno orienta su Comentario al Corpus Dionisiacum de la misma manera que Gregorio por la revelación de este misterio, que busca entender racionalmente. El estudio se detiene en las citas tomadas por el Doctor Universalis de los Moralia en SMT II, la Ep I, la Ep V y la Ep IX, para descubrir cuál es, concretamente, la influencia de Gregorio Magno sobre Alberto Magno en la intelección del problema razón y revelación.Although the influence of Gregory Magnus was crucial for the history of practical theological thought in the Middle Ages -being the most cited author in Thomas Aquinas' STh after Augustine- his influence over Albertus Magnus has not been studied recently. In effect, Albertus Magnus's Commentary on Corpus Di-onysiacum is guided, in the same way as Gregory, by the revelation of this mystery, which he seeks to understand rationally. This study focuses on the citations from the Moralia that Doctor Universalis uses in SMT II (Super Mysticam Theologiam Dionysii, the Ep. I, the Ep.V and the Ep. IX, in an effort to concretely discover what Gregory Magnus' influence was over Albertus Magnus in his understanding of the problem of reason and revelation.

  8. The effect of a metalloproteinase inhibitor (GI5402) on tumor necrosis factor-alpha (TNF-alpha) and TNF-alpha receptors during human endotoxemia

    NARCIS (Netherlands)

    Dekkers, P. E.; Lauw, F. N.; ten Hove, T.; te Velde, A. A.; Lumley, P.; Becherer, D.; van Deventer, S. J.; van der Poll, T.

    1999-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is released from the cell surface by cleavage of pro-TNF-alpha by metalloproteinases (MPs). In cell cultures, inhibition of MPs has been found not only to reduce the release of TNF-alpha, but also to enhance the surface expression of TNF-alpha and TNF-alpha

  9. Conocimientos sobre sexualidad y su influencia en el embarazo en adolescentes

    OpenAIRE

    Carmina Alexandra García Macías; Leticia Remón Ramírez; Josefa Margarita Miranda Vázquez; Silvia Rosana Defaz Taipe

    2017-01-01

    Introducción: El embarazo en la adolescencia es en la actualidad un problema de salud que genera serias consecuencias personales, sociales y económicas, con repercusión en la salud individual, familiar y colectiva. Objetivo: Identificar los conocimientos sobre la sexualidad y su influencia en el embarazo en la adolescencia. Métodos: Se realizó un estudio observacional analítico, transversal, en un universo de 80 adolescentes de 15 a 19 años del Equipo Urbano de Salud 23 Latacunga, a q...

  10. INFLUENCIA DEL DESARROLLO MOTRIZ EN EL APRENDIZAJE DE LA ESCRITURA, ASÍ COMO EN LAS COMPETENCIAS

    OpenAIRE

    Soto-Ruiz, María del Pilar

    2012-01-01

    La idea central de esta investigación fue examinar el desarrollo de los patrones motrices básicos en niños de infantil y su posible influencia en el proceso de aprendizaje, concretamente en la escritura. La metodología empleada fue de tipo exploratoria-descriptiva y correlacional, dirigida a una muestra de 40 niños de 5 años, a los cuales se les aplicó una serie de pruebas para valorar la motricidad, escritura y calificaciones escolares. El análisis e interpretación de los resu...

  11. Influencia de la familia en los trastornos alimenticios (Estudio de un caso clínico)

    OpenAIRE

    González Gómez, Dulce María

    2016-01-01

    Los trastornos de la conducta alimentaria son un conjunto de patologías cuya prevalencia no deja de aumentar, encontrando casos cada vez a edades más tempranas y siendo mucho más frecuentes en mujeres. Su tratamiento no es nada fácil, pues la curación completa suele conllevar años y en un gran número de casos se produce cronificación o recaídas. Su etiología, como en muchas enfermedades, es el resultado de una compleja interacción entre factores genéticos e influencia del ambiente exter...

  12. Influencia de la humedad en el ensayo de resistencia de los ladrillos de suelo-cemento

    OpenAIRE

    Lima, José I.; Escobar Martín, Dunia

    1994-01-01

    A través de un diseño experimental adecuado se pretende mostrar la influencia de la humedad en el ensayo a compresión de los ladrillos de suelo-cemento, obteniendo las ecuaciones que muestran esta relación. Su generalización posterior permitió elaborar una matriz de correlación de las resistencias con las diferentes humedades de ensayo, de forma tal que se pueda ensayar con una humedad dada y estimar la resistencia que tendrá esa muestra para diferentes valores de humedad, con un buen nive...

  13. La motivación laboral y su influencia en la empresa

    OpenAIRE

    Jiménez Cacho, Raquel

    2017-01-01

    Este proyecto se centra en un tema de gran interés como es la motivación laboral y su influencia en la empresa. Como sabemos este tema no es nuevo y se ha analizado y estudiado desde hace mucho tiempo, debido a la incidencia que tiene en el mundo laboral, económico y social. La motivación laboral lleva una trayectoria positiva en cuanto a su estudio e importancia, gracias a su estrecha relación con los problemas, soluciones, costes, beneficios y ventajas competitivas de las empresas. Para ...

  14. Estructura portante y estructura formal: Mies Van Der Rohe y su influencia sobre la arquitectura paulista

    OpenAIRE

    Mahfuz, Edson da Cunha

    2014-01-01

    El artículo trata de la posible influencia de Mies van der Rohe sobre la arquitectura paulista. Su característica más evidente es el rol de la estructura portante en la construcción de la forma. El uso de un número reducido de soportes busca liberar el suelo para actividades colectivas. The article describes the possible influence of Mies van der Rohe on the architecture practiced in São Paulo. Its most noticeable feature is the role of the structure on the definition of the overall art...

  15. Influencia del aceite de coco en enfermos de alzhéimer a nivel cognitivo.

    OpenAIRE

    De la Rubia Ortí, Jose Enrique; Sánchez Álvarez, Carmen; Selvi Sabater, Pablo; Bueno Cayo, Alma María; Sancho Castillo, Sandra; Julián Rochina, Mariano; Hu Yang, Iván

    2017-01-01

    La enfermedad de Alzheimer es a día de hoy la demencia neurodegenerativa con mayor prevalencia en el primer mundo. Este hecho, unido a la falta de tratamiento farmacológico que cure la enfermedad, hace que se estudien nuevas estrategias terapéuticas no farmacológicas como es la administración de nutrientes. En este sentido, destaca la posible influencia del aceite de coco como fuente energética alternativa, capaz de frenar la muerte neuronal que se produce de modo progresivo en esta enfermeda...

  16. La influencia de las guerras civiles sobre la represión estatal en posguerras

    OpenAIRE

    Herreros, Francisco

    2014-01-01

    En este artículo se analizan los determinantes de la represión estatal en posguerras. Su argumento principal es que ciertas dinámicas de las guerras civiles explican la variación en represión estatal en la posguerra. Para comprobar la influencia de las guerras civiles en la represión estatal, se emplea una base de datos que incluye a todos los países que han experimentado una guerra civil en el período 1976-2009. Los resultados muestran que una victoria rebelde en la guerra o un compromiso en...

  17. Influencia del tempo de la música en las emociones

    Directory of Open Access Journals (Sweden)

    Jonathan Azael Caballero-Meneses

    2010-01-01

    exposición de 24 estudiantes de licenciatura a treinta extractos musicales de distinto tempo. Además se evaluó la posible modulación de la relación tempo-valencia por el rasgo de personalidad extroversión/introversión. Los resultados confirmaron la influencia del tempo sobre el arousal, pero no sobre la valencia, así como una posible mediación de la dimensión de personalidad introversión-extroversión sobre la valencia.

  18. Culpabilidad sexual en jóvenes: influencia de las actitudes y la experiencia sexual

    OpenAIRE

    Juan Carlos Sierra; Felipe Perla; Pablo Santos-Iglesias

    2011-01-01

    La culpabilidad sexual es un factor determinante de la conducta sexual. El objetivo del presente estudio fue analizar la culpabilidad sexual en una muestra de 594 jóvenes salvadoreños con edades comprendidas entre 14 y 18 años, seleccionados mediante un procedimiento no aleatorio, con el propósito de determinar la influencia que sobre la misma tienen una serie de variables sociodemográficas y de actitudes hacia la sexualidad. Los participantes contestaron el Inventario de Culpabilidad Sexual ...

  19. Absceso paravalvular en la endocarditis bacteriana: influencia en el pronóstico postoperatorio

    OpenAIRE

    Varela Barca, Laura; López Menéndez, Jose; Martín García, Miren; Redondo Palacios, Ana; Centella Hernández, Tomasa; Miguelena Hycka, Javier; Muñoz Pérez, Rafael; Rodríguez-Roda Stuart, Jorge

    2017-01-01

    Objetivo: El absceso paravalvular (AbP) aumenta la mortalidad, la complejidad y las complicaciones asociadas a la cirugía de endocarditis infecciosa (EI). Analizamos la influencia del AbP en las distintas formas de presentación de endocarditis bacteriana. Métodos: Estudio retrospectivo, observacional, incluyendo a todos los pacientes intervenidos de EI entre 2002 y 2015, y realizando seguimiento clínico tras el alta. Resultados: Se intervino a 169 pacientes, presentando AbP el 33% de lo...

  20. La influencia del apego y del trauma infantil en la psicopatología del adulto

    OpenAIRE

    Marrodán Muro, Isabel

    2015-01-01

    En el presente trabajo se hace una revisión bibliográfica de la influencia de dos factores personales de la infancia, apego y trauma infantil, en la psicopatología de la edad adulta. En la primera parte se analiza cómo afecta el apego a la hora de sufrir trastornos mentales en un futuro, y se demuestra que un apego inseguro es un factor de riesgo a la hora de sufrir psicopatologías. La segunda parte trata de cómo influye el trauma infantil (abuso sexual, maltrato físico o psicológico o violen...

  1. La influencia de la musicoterapia en ni??os con disfemia

    OpenAIRE

    P??rez Bazoco, M??nica

    2015-01-01

    En este trabajo se pretende realizar una peque??a investigaci??n sobre la influencia que tiene la musicoterapia en los ni??os que presentan disfemia. La musicoterapia es un medio de rehabilitaci??n que incide tanto desde el punto de vista fisiol??gico (como puede ser la ejercitaci??n de la voz), como desde la perspectiva emocional e intelectual, proporcionando un desarrollo afectivo y cognoscitivo. Por tanto, la din??mica planteada de modelos mel??dicos y r??tmicos parece repercutir en el des...

  2. Las organizaciones contemporáneas tipo MP3 y su influencia cultural

    OpenAIRE

    Macías Cardona, Hugo

    2011-01-01

    En este artículo se hace una reflexión sobre la influencia cultural de organizaciones contemporáneas con estructuras des-jerarquizadas y procesos internos no secuenciales, que el profesor Richard Sennet ha llamado organizaciones MP3. A partir de las estructuras organizacionales descritas por Álvaro Zapata, la distinción entre trabajo y labor de Hannah Arendt, los mecanismos de vigilancia foucaultianos y una contextualización en Colombia, se analiza la baja lealtad institucional, la disminució...

  3. Uso e influencia de la televisión en la infancia

    OpenAIRE

    Arroyo Jiménez, Isabel

    2012-01-01

    Esta investigación está contextualizada en torno al uso e influencia que ejerce la televisión en la infancia. En concreto hemos escogido un grupo de niños del tercer ciclo de Educación Primaria (10-12 años). Primeramente, tratamos de comprobar el uso que hacen de la televisión los alumnos que hemos tomado como muestra así como el tipo de programas que ven. Posteriormente, analizaremos una pequeña muestra de esos programas más seguidos por nuestros alumnos encuestados. Para ello, partire...

  4. Influencia de la electroestimulación y lesión del ligamento cruzado anterior

    OpenAIRE

    Nuñez, Alberto

    2011-01-01

    En este trabajo se estudio en profundidad la lesión del ligamento cruzado anterior (LCA) y la influencia de la electroestimulación. En la primer parte del trabajo se desarrolló un protocolo para aplicar electroestimulación a diez pacientes que sufrieron lesión del LCA y que habían sido sometidos a cirugía. En la segunda parte, se indagó en profundidad a dichos pacientes a través de una entrevista sobre las causas de la lesión, el contexto en que ocurrió la lesión, el proceso pr...

  5. INFLUENCIA DEL CULTIVO INTERCALADO EN LA PRODUCCIÓN Y CALIDAD DEL FRUTO DE TOMATE CEREZA

    OpenAIRE

    Fabricio Rossi; Edmilson José Ambrosano; Eliana Aparecida Schammass; Glaucia María Bovi Ambrosano; Nivaldo Guirado; Fabio Luis Ferreira Días; Roberto Antonio Arévalo; Edna Ivani Bertoncini

    2013-01-01

    El presente trabajo tiene por objetivo determinar la influencia en la cosecha y calidad de los frutos de Solanum lycopersicum L. (1753) cv. cereza [Lycopersicum esculentum Mill. 1768] (tomate) en convivencia con cultivos intercalares de cinco Fabaceae, plantas auxiliadoras en la agricultura y dos tratamientos con y sin residuos de cosecha de Zea mayz L. El estudio fue im- plantado en el Polo Centro Sul, Piracicaba-SP. Brasil, en suelo Argisol rojo-amarillo distrófico. El diseño experimental f...

  6. Las organizaciones contemporáneas tipo mp3 y su influencia cultural

    Directory of Open Access Journals (Sweden)

    Hugo Macías Cardona

    2011-06-01

    Full Text Available En este artículo se hace una reflexión sobre la influencia cultural de organizaciones contemporáneas con estructuras des-jerarquizadas y procesos internos no secuenciales, que el profesor Richard Sennet ha llamado organizaciones MP3. A partir de las estructuras organizacionales descritas por Álvaro Zapata, la distinción entre trabajo y labor de Hannah Arendt, los mecanismos de vigilancia foucaultianos y una contextualización en Colombia, se analiza la baja lealtad institucional, la disminución de la confianza informal entre quienes laboran y el debilitamiento del conocimiento institucional.

  7. Chromosomal aberrations induced by alpha particles; Aberraciones cromosomicas inducidas por particulas {alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Brena V, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: cgc@nuclear.inin.mx

    2005-07-01

    The chromosomal aberrations produced by the ionizing radiation are commonly used when it is necessary to establish the exposure dose of an individual, it is a study that is used like complement of the traditional physical systems and its application is only in cases in that there is doubt about what indicates the conventional dosimetry. The biological dosimetry is based on the frequency of aberrations in the chromosomes of the lymphocytes of the individual in study and the dose is calculated taking like reference to the dose-response curves previously generated In vitro. A case of apparent over-exposure to alpha particles to which is practiced analysis of chromosomal aberrations to settle down if in fact there was exposure and as much as possible, to determine the presumed dose is presented. (Author)

  8. Development of thermal conditioning technology for Alpha-containment wastes: Alpha-contaminated waste incineration technology

    International Nuclear Information System (INIS)

    Kim, Joon Hyung; Kim, Jeong Guk; Yang, Hee Chul; Choi, Byung Seon; Jeong, Myeong Soo

    1999-03-01

    As the first step of a 3-year project named 'development of alpha-contaminated waste incineration technology', the basic information and data were reviewed, while focusing on establishment of R and D direction to develop the final goal, self-supporting treatment of α- wastes that would be generated from domestic nuclear industries. The status on α waste incineration technology of advanced states was reviewed. A conceptual design for α waste incineration process was suggested. Besides, removal characteristics of volatile metals and radionuclides in a low-temperature dry off-gas system were investigated. Radiation dose assessments and some modification for the Demonstration-scale Incineration Plant (DSIP) at Korea Atomic Energy Research Institute (KAERI) were also done

  9. La influencia externa en las políticas educativas de Argentina, Brasil y Chile (1990-2006)

    OpenAIRE

    Rambla, Francesc Xavier,

    2009-01-01

    El objetivo del artículo es analizar el papel que juega la influencia internacional en el diseño y aplicación de políticas educativas en el Cono Sur. Específicamente pretende explorar el proceso a través del cual las ideas, recomendaciones y metas globales modelan las políticas educativas latinoamericanas. Para ello, el artículo se centra en el programa de Educación para Todos en el Acuerdo General de Comercio de Servicios, analizando los mecanismos de influencia externa que intervienen en ca...

  10. Relaciones sociales y trayectorias biográficas : hacia un enfoque comprensivo de los modos de influencia

    OpenAIRE

    Bourdon, Sylvain

    2009-01-01

    El objetivo del presente texto es proponer algunos elementos para un enfoque comprensivo de la influencia de las relaciones en las trayectorias biográficas. El análisis se apoya en los datos de un estudio longitudinal sobre el papel que desempeñan la familia y las redes en la perseverancia en los estudios, realizado con 96 jóvenes que inician su trayectoria postsecundaria. En lugar de abordar la influencia en términos de características sociales, o a partir de un enfoque estructural de las re...

  11. Calibration of sources for alpha spectroscopy systems

    International Nuclear Information System (INIS)

    Freitas, I.S.M.; Goncalez, O.L.

    1992-01-01

    This paper describes the calibration methodology for measuring the total alpha activity of plane and thin sources with the Alpha Spectrometer for Silicon Detector in the Nuclear Measures and Dosimetry laboratory at IEAv/CTA. (author)

  12. CERN Radiation Protection (RP) calibration facilities

    CERN Document Server

    AUTHOR|(CDS)2082069; Macián-Juan, Rafael

    Radiation protection calibration facilities are essential to ensure the correct operation of radiation protection instrumentation. Calibrations are performed in specific radiation fields according to the type of instrument to be calibrated: neutrons, photons, X-rays, beta and alpha particles. Some of the instruments are also tested in mixed radiation fields as often encountered close to high-energy particle accelerators. Moreover, calibration facilities are of great importance to evaluate the performance of prototype detectors; testing and measuring the response of a prototype detector to well-known and -characterized radiation fields contributes to improving and optimizing its design and capabilities. The CERN Radiation Protection group is in charge of performing the regular calibrations of all CERN radiation protection devices; these include operational and passive dosimeters, neutron and photon survey-meters, and fixed radiation detectors to monitor the ambient dose equivalent, H*(10), inside CERN accelera...

  13. Collective Thomson Scattering diagnostic for fusion product alpha particle measurement

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.; Kondoh, Takashi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2000-03-01

    In JT-60U, a pulsed CO{sub 2} laser (10.6 {mu}m 10 MW) have been developed to measure ion temperature and velocity distribution of fast ions to demonstrate feasibility of measurements of confined alpha particles in ITER. High power pulsed CO{sub 2} laser and heterodyne receiver system (a quantum-well infrared photodetector, QWIP) has been developed and installed in the diagnostic room (in collaboration with the Oak Ridge National Laboratory team). We describe the present states of the JT-60U CTS (Collective Thomson Scattering) system and also present a calculation of the scattered spectrum associated with the density and velocity distribution of energetic fusion produced alpha particles. Scattering of CO{sub 2} radiation is evaluated for the plasma condition for both ITER and JT-60U. (author)

  14. Alpha-ray spectrometry at high temperature by using a compound semiconductor detector.

    Science.gov (United States)

    Ha, Jang Ho; Kim, Han Soo

    2013-11-01

    The use of conventional radiation detectors in harsh environments is limited by radiation damage to detector materials and by temperature constraints. We fabricated a wide-band gap semiconductor radiation detector based on silicon carbide. All the detector components were considered for an application in a high temperature environment like a nuclear reactor core. The radiation response, especially to alpha particles, was measured using an (241)Am source at variable operating voltages at room temperature in the air. The temperature on detector was controlled from 30°C to 250°C. The alpha-particle spectra were measured at zero bias operation. Even though the detector is operated at high temperature, the energy resolution as a function of temperature is almost constant within 3.5% deviation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Enzyme replacement therapy for alpha-mannosidosis

    DEFF Research Database (Denmark)

    Borgwardt, Line Gutte; Dali, Christine I.; Fogh, J

    2013-01-01

    Alpha-mannosidosis (OMIM 248500) is a rare lysosomal storage disease (LSD) caused by alpha-mannosidase deficiency. Manifestations include intellectual disabilities, facial characteristics and hearing impairment. A recombinant human alpha-mannosidase (rhLAMAN) has been developed for weekly intrave...... intravenous enzyme replacement therapy (ERT). We present the preliminary data after 12 months of treatment....

  16. THE ALPHA/BETA-HYDROLASE FOLD

    NARCIS (Netherlands)

    OLLIS, DL; CHEAH, E; CYGLER, M; FROLOW, F; FRANKEN, SM; HAREL, M; REMINGTON, SJ; SILMAN, [No Value; SCHRAG, J; SUSSMAN, JL; VERSCHUEREN, KHG; GOLDMAN, A

    We have identified a new protein fold-the alpha/beta-hydrolase fold-that is common to several hydrolytic enzymes of widely differing phylogenetic origin and catalytic function. The core of each enzyme is similar: an alpha/beta-sheet, not barrel, of eight beta-sheets connected by alpha-helices. These

  17. The evaluation of the real alpha value in Brazil and its projection until the year 2050

    International Nuclear Information System (INIS)

    Perez, Clarice F.; Ghobril, Carlos N.; Sordi, Gian Maria; Sahyun, Adelia

    2017-01-01

    When a cost-benefit analysis is applied to the optimization of practices involving radiation protection, the alpha value is used to determine the amount of money required to be invested in a practice to minimize radiation doses to acceptable levels. The alpha value is often linked to the gross domestic product (GDP) per capita, so the monetary reference value of person-Sievert can often be different in each country. Evaluation of the alpha value in Brazil was performed in 1993 and 2000 making use of the procedure advised by ICRP to produce projections up to 2015 and subsequently in 2004 by using the procedure recommended by the IAEA. This paper, in response to the social and economic situation in Brazil, calculates the alpha value and compares it with the projections of the 1993 and 2000 papers and includes a dollar correction to take account of the differences in the purchasing power from that time. This procedure illustrates the significant gap of value in use and that the actual value should be two to three times higher. By GDP per capita, the authors could calculate the alpha value updated to various countries including the European Union and compare them with the official value currently in use. In conclusion, it is believed that all countries that adopt an alpha value should upgrade it to the present day. (authors)

  18. The Evaluation of The Real Alpha Value in Brazil and its Projection until The Year 2050.

    Science.gov (United States)

    Perez, Clarice F; Ghobril, Carlos N; Sordi, Gian Maria; Sahyun, Adelia

    2017-04-01

    When a cost-benefit analysis is applied to the optimization of practices involving radiation protection, the alpha value is used to determine the amount of money required to be invested in a practice to minimize radiation doses to acceptable levels. The alpha value is often linked to the gross domestic product (GDP) per capita, so the monetary reference value of person-Sievert can often be different in each country. Evaluation of the alpha value in Brazil was performed in 1993 and 2000 making use of the procedure advised by ICRP to produce projections up to 2015 and subsequently in 2004 by using the procedure recommended by the IAEA. This paper, in response to the social and economic situation in Brazil, calculates the alpha value and compares it with the projections of the 1993 and 2000 papers and includes a dollar correction to take account of the differences in the purchasing power from that time. This procedure illustrates the significant gap of value in use and that the actual value should be two to three times higher. By GDP per capita, the authors could calculate the alpha value updated to various countries including the European Union and compare them with the official value currently in use. In conclusion, it is believed that all countries that adopt an alpha value should upgrade it to the present day. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Nature of the pygmy dipole resonance in Ce-140 studied in (alpha, alpha 'gamma) experiments

    NARCIS (Netherlands)

    Savran, D.; Babilon, M.; van den Berg, A.M.; Harakeh, M.N.; Hasper, J.; Matic, A.; Wörtche, H.J.; Zilges, A.

    2006-01-01

    A concentration of electric-dipole excitations below the particle threshold, which is frequently denoted as the pygmy dipole resonance, has been studied in the semimagic nucleus Ce-140 in (alpha, alpha(')gamma) experiments at E-alpha=136 MeV. The technique of alpha-gamma coincidence experiments

  20. Radiation monitor

    International Nuclear Information System (INIS)

    Pao, C.T.; Green, W.K.

    1978-01-01

    A system for indicating radiation from a radioactive fluid such as a gas wherein simultaneous indications of the activity concentration of radioactivity of the gas, the radiation dose rate and average energy of the radiation are provided

  1. Radiation protection

    International Nuclear Information System (INIS)

    Ures Pantazi, M.

    1994-01-01

    This work define procedures and controls about ionizing radiations. Between some definitions it found the following topics: radiation dose, risk, biological effects, international radioprotection bodies, workers exposure, accidental exposure, emergencies and radiation protection

  2. Biological Effects of Radiation

    International Nuclear Information System (INIS)

    Jatau, B.D.; Garba, N.N.; Yusuf, A.M.; Yamusa, Y. A.; Musa, Y.

    2013-01-01

    In earlier studies, researchers aimed a single particle at the nucleus of the cell where DNA is located. Eighty percent of the cells shot through the nucleus survived. This contradicts the belief that if radiation slams through the nucleus, the cell will die. But the bad news is that the surviving cells contained mutations. Cells have a great capacity to repair DNA, but they cannot do it perfectly. The damage left behind in these studies from a single particle of alpha radiation doubled the damage that is already there. This proved, beyond a shadow of doubt, those there biological effects occur as a result of exposure to radiation, Radiation is harmful to living tissue because of its ionizing power in matter. This ionization can damage living cells directly, by breaking the chemical bonds of important biological molecules (particularly DNA), or indirectly, by creating chemical radicals from water molecules in the cells, which can then attack the biological molecules chemically. At some extent these molecules are repaired by natural biological processes, however, the effectiveness of this repair depends on the extent of the damage. The interaction of ionizing with the human body, arising either from external sources outside the body or from internal contamination of the body by radioactive materials, leads to the biological effects which may later show up as a clinical symptoms. Basically, this formed the baseline of this research to serve as a yardstick for creating awareness about radiation and its resulting effects.

  3. Alternative splicing of T cell receptor (TCR) alpha chain transcripts containing V alpha 1 or V alpha 14 elements.

    Science.gov (United States)

    Mahotka, C; Hansen-Hagge, T E; Bartram, C R

    1995-10-01

    Human acute lymphoblastic leukemia cell lines represent valuable tools to investigate distinct steps of the complex regulatory pathways underlying T cell receptor recombination and expression. A case in point are V delta 2D delta 3 and subsequent V delta 2D delta 3J alpha rearrangements observed in human leukemic pre-B cells as well as in normal lymphopoiesis. The functional expression of these unusual (VD) delta (JC) alpha hybrids is almost exclusively prevented by alternative splicing events. In this report we show that alternative splicing at cryptic splice donor sites within V elements is not a unique feature of hybrid TCR delta/alpha transcripts. Among seven V alpha families analyzed by RT-PCR, alternatively spliced products were observed in TCR alpha recombinations containing V alpha 1 or V alpha 14 elements. In contrast to normal peripheral blood cells and thymocytes, the leukemia cell line JM expressing functional V alpha 1J alpha 3C alpha transcripts lacked evidence of aberrant TCR alpha RNA species.

  4. Ionizing radiation

    International Nuclear Information System (INIS)

    Kruger, J.

    1989-01-01

    Ionizing radiation results in biological damage that differs from other hazardous substances and is highly dangerous to man. Ionizing radiation cannot be perceived by man's sense organs and the biological damage cannot be detected immediately afterwards (except in very high doses). Every human being is exposed to low doses of radiation. The structure of the atom; sources of ionizing radiation; radiation units; biological effects; norms for radiation protection; and the national control in South Africa are discussed. 1 fig., 5 refs

  5. Radiation dosimetry

    CERN Document Server

    Hine, Gerald J; Hine, Gerald J

    1956-01-01

    Radiation Dosimetry focuses on the advancements, processes, technologies, techniques, and principles involved in radiation dosimetry, including counters and calibration and standardization techniques. The selection first offers information on radiation units and the theory of ionization dosimetry and interaction of radiation with matter. Topics include quantities derivable from roentgens, determination of dose in roentgens, ionization dosimetry of high-energy photons and corpuscular radiations, and heavy charged particles. The text then examines the biological and medical effects of radiation,

  6. Influencias platónicas en el pensamiento de clemente de alejandría

    Directory of Open Access Journals (Sweden)

    José Antonio Llamas Martínez

    2001-01-01

    Full Text Available Las obras de Clemente de Alejandría son el reflejo más exacto de la filosofía platónica. La influencia de Platón fue bastante evidente durante el periodo helenístico. Clemente de Alejandría es un intelectual formado a la luz de diversas escuelas helenísticas. Sin embargo, esta razón no es suficiente para confirmar tal influencia. Es cierto que Clemente elige a Platón y no a Aristóteles como inspiración de su pensamiento cristiano. Hubo otros intelectuales que, no sólo no hicieron referencia a ningún filósofo, sino que losrechazaron abiertamente. Clemente admira tanto a Platón que identifica su filosofía como un auténtico testamento, con un valor realmente propedéutico, como hubiera sido el testamento para la nueva filosofía cristiana

  7. El seminario de Wachsmann en Japón: Las influencias compartidas

    Directory of Open Access Journals (Sweden)

    Martino Peña Fernández-Serrano

    2017-11-01

    Full Text Available En 1955 Konrad Wachsmann, arquitecto alemán de origen judío y establecido en Estados Unidos, impartió el seminario denominado The Wachsmann Seminar en Japón. En el taller de Wachsmann se ejemplifican las influencias directas que el maestro transmite a una joven generación de estudiantes japoneses de arquitectura entre los cuales se encontraban algunos de los futuros componentes del grupo Metabolista. Kenzo Tange es el organizador del taller y a través de él se materializó el resultado en el edifico denominado Big Roof, situado en la exposición universal que se celebró en Osaka en 1970. Esta edificación, que sirve de entrada al complejo, aloja varias exposiciones entre las que se encuentraba la denominada ciudad aérea, donde arquitectos colocaron sus artefactos. En esta exposición se utiliza la cubierta como gran contenedor de células habitacionales diseñadas por algunos componentes del grupo Metabolista y otros grupos internacionales como Archigram. Se constatan por tanto las influencias directas e indirectas de una generación de arquitectos sobre otra más joven, y a su vez entre ellos, derivadas del seminario de Wachsmann que fue posible gracias al inicio de los viajes aéreos comerciales que siguen a los militares.

  8. INFLUENCIA DEL TEMPO DE LA MÚSICA EN LAS EMOCIONES

    Directory of Open Access Journals (Sweden)

    Jonathan Azael Caballero-Meneses

    2010-01-01

    Full Text Available Se sabe que la música puede influir en dos componentes de lasemociones: el arousal y la valencia. En particular, se ha reportadoque el tempo o rapidez de la música está directamenterelacionado con el arousal, aunque su relación con la valenciao medida de afecto no es aún clara. En este trabajo se analizóla influencia del tempo en ambos componentes mediante laexposición de 24 estudiantes de licenciatura a treinta extractosmusicales de distinto tempo. Además se evaluó la posiblemodulación de la relación tempo-valencia por el rasgo de personalidadextroversión/introversión. Los resultados confirmaronla influencia del tempo sobre el arousal, pero no sobrela valencia, así como una posible mediación de la dimensiónde personalidad introversión-extroversión sobre la valencia.

  9. De la influencia al poder: elementos para una mirada foucaultiana al Liderazgo

    Directory of Open Access Journals (Sweden)

    Juan Javier Saavedra Mayorga

    2013-10-01

    Full Text Available El artículo tiene como objetivo contribuir a la construcción de una mirada crítica al liderazgo. Examina la posibilidad de estudiar el problema central del liderazgo, el de la influencia, desde un punto de vista más amplio, el de las relaciones de poder entre los individuos, y en particular desde la teoría del poder de Michel Foucault. El artículo hace una revisión de la obra de Michel Foucault y de su utilización por parte de los estudios organizacionales, y propone la tesis según la cual su filosofía, que señala una estrecha relación entre el discurso y los dispositivos para el ejercicio del poder, puede contribuir a la comprensión de los mecanismos a través de los cuales se ejerce la influencia en las organizaciones. Para desarrollar esta tesis de exploran tres formas complementarias de estudiar el liderazgo desde la perspectiva de Foucault: el liderazgo como discurso, como tecnología de poder y como técnica del yo.

  10. La influencia de la televisión en una campaña electoral

    Directory of Open Access Journals (Sweden)

    ELISABETH NOELLE-NEUMANN

    1978-01-01

    Full Text Available Se examina el efecto de los medios de comunicación de masas sobre las elecciones en base a datos relativos las elecciones federales de la República Federal de Alemania que tuvieron lugar en 1965, 1972 y 1976. Se sugiere que durante una campaña electoral la opinión pública seguirá las expectativas mostradas por los medios y la visibilidad que éstos dan a las diferentes partes. Se perfilan los cambios en la opinión pública que alteran el clima político mediante el análisis de datos recabados en varios períodos. Dichos análisis revelan que no se puede demostrar la existencia de una relación causal entre las sentencias políticas que aparecen en la televisión y la opinión pública. Si bien parece que la televisión tenga alguna influencia en el clima de opinión, el problema de cómo verificar dicha influencia permanece irresuelto.

  11. Influencia de la estrategia "toma de decisiones" en el autoconcepto de adolescentes consumidores de alcohol

    Directory of Open Access Journals (Sweden)

    Reyna Isabel Hernández Pedroza

    2015-12-01

    Full Text Available El objetivo de esta investigación fue determinar la influencia de la estrategia "toma de decisiones" en el autoconcepto de adolescentes consumidores de alcohol. Se aplicó un estudio longitudinal, pre-experimental. Se incluyeron 30 adolescentes, previo consentimiento informado de estudiantes y padres. La recolección de datos se realizo con AUDIT, test de conflicto decisional y The Tennessee Self-Concep Scale (TSCS. Se encontró que la edad promedio fue 16.56 ± 0.85 años, 60% hombres, el 100% de los adolescentes presentaron conflicto decisional. El 100% habían consumido alcohol alguna vez en su vida. No se encontró diferencia estadísticamente significativa entre el autoconcepto pre y post intervención (p = 0.27, excepto en la dimensión Yo moral (p = 0.01. Se concluye de acuerdo a los resultados obtenidos en la pre y post intervención que la estrategia de intervención tuvo una influencia en la dimensión del autoconcepto Yo Moral del adolescente consumidor de alcohol. Es posible que esto influyera en la percepción de sí mismo al encontrarse con la realidad de que por primera vez consideraba su capacidad o incapacidad para tomar decisiones.

  12. La influencia social de los medios de comunicación en Twitter

    Directory of Open Access Journals (Sweden)

    Karines Rodríguez Díaz

    2017-06-01

    Full Text Available En este artículo se expone cómo se desarrolla la influencia social de los medios de comunicación sobre los usuarios en Twitter, durante la celebración de la VII Cumbre de la Asociación de Estados del Caribe (AEC. La investigación parte del análisis de un corpus de 1500 tuits con las etiquetas temáticas #CubaCaribe, #VIICumbreAEC, #CumbreAEC. Utilizando el análisis del discurso mediado por computador, los resultados muestran la habilidad de influencia de los medios de comunicación a través de patrones de repetición-reacción y en la construcción del consenso sobre la valoración del acontecimiento. El reporte de caso explica cómo los parlamentos mediáticos repercuten en la comunidad de usuarios en el contexto microblogging.

  13. Factores determinantes de la actividad en el mercado laboral gallego. Influencia del género

    Directory of Open Access Journals (Sweden)

    Mª Carmen Sánchez Sellero

    2013-04-01

    Full Text Available En este trabajo se estudian las características personales que determinan la actividad (ocupación o paro en la población gallega. Para ello se construye el modelo de actividad, en el cual se estima la probabilidad de que una persona en edad de trabajar forme parte de la población activa.Una vez estimados los parámetros del modelo mediante regresión logística binaria, se calculan las probabilidades de actividad condicionadas a distintas características personales, para evaluar la influencia real de las mismas en la forma en que un individuo se integra en el mercado de trabajo. Del análisis empírico se obtiene que la característica más destacada es el sexo, y que la influencia de las demás variables sobre las distintas probabilidades varía en función del sexo de la persona analizada.

  14. Measurement and analysis of $\\alpha$ particle induced reactions on yttrium

    CERN Document Server

    Singh, N L; Chintalapudi, S N

    2000-01-01

    Excitation functions for /sup 89/Y[( alpha ,3n); ( alpha ,4n); ( alpha , p3n); ( alpha , alpha n); ( alpha , alpha 2n)] reactions were measured up to 50 MeV using stacked foil activation technique and HPGe gamma ray spectroscopy method. The experimental data were compared with calculations considering equilibrium as well as preequilibrium reactions according to the hybrid model of Blann (ALICE/90). For ( alpha , xnyp) type of reactions, the precompound contributions are described by the model. There seems to be indications of direct inelastic scattering effects in ( alpha , alpha xn) type of reactions. To the best of our knowledge, the excitation functions for ( alpha ,4n), ( alpha , p3n), ( alpha , alpha n) and ( alpha , alpha 2n) reactions were measured for the first time. (23 refs).

  15. Measurement and analysis of alpha particle induced reactions on yttrium

    Energy Technology Data Exchange (ETDEWEB)

    Singh, N.L.; Gadkari, M.S. [Baroda Univ. (India). Dept. of Physics; Chintalapudi, S.N. [IUC-DAEF Calcutta Centre, Calcutta (India)

    2000-05-01

    Excitation functions for {sup 89}Y[({alpha},3n);({alpha},4n);({alpha},p3n);({alpha},{alpha}n);({alpha},{alpha}2n)] reactions were measured up to 50 MeV using stacked foil activation technique and HPGe gamma ray spectroscopy method. The experimental data were compared with calculations considering equilibrium as well as preequilibrium reactions according to the hybrid model of Blann (ALICE/90). For ({alpha},xnyp) type of reactions, the precompound contributions are described by the model. There seems to be indications of direct inelastic scattering effects in ({alpha},{alpha}xn) type of reactions. To the best of our knowledge, the excitation functions for ({alpha},4n), ({alpha},p3n), ({alpha},{alpha}n) and ({alpha},{alpha}2n) reactions were measured for the first time. (orig.)

  16. First fast-ion D-alpha (FIDA) measurements and simulations on C-2U

    Energy Technology Data Exchange (ETDEWEB)

    Bolte, N. G., E-mail: nbolte@TriAlphaEnergy.com; Gupta, D.; Onofri, M.; Dettrick, S.; Granstedt, E. M.; Petrov, P. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); Stagner, L. [University of California, Irvine, Irvine, California 92697 (United States)

    2016-11-15

    The first measurements of fast-ion D-alpha (FIDA) radiation have been acquired on C-2U, Tri Alpha Energy’s advanced, beam-driven field-reversed configuration (FRC). These measurements are also forward modeled by FIDASIM. This is the first measurement and simulation of FIDA carried out on an FRC topology. FIDA measurements are made of Doppler-shifted Balmer-alpha light from neutralized fast ions using a bandpass filter and photomultiplier tube. One adjustable line-of-sight measured signals at eight locations and eight times during the FRC lifetime over 26 discharges. Filtered signals include only the highest energy ions (>6 keV) and share some salient features with the FIDASIM result. Highly Doppler-shifted beam radiation is also measured with a high-speed camera and is spatially well-correlated with FIDASIM.

  17. Effect of radioactive isotope 32P upon alpha amylase activity and glucose concentration in chickens

    International Nuclear Information System (INIS)

    Kraljevic, P.; Emanovic, D.; Simpraga, M.; Nejedli, S.; Stojevic, Z.

    1996-01-01

    An attempt has been made to investigate whether alpha amylase activity and glucose concentration in blood plasma can serve as the help in establishing on early diagnosis of organic or functional damage caused by ionizing radiation in chickens. Fifty day old hybrid chickens of heavy 'Jata' breeds of both sexes, were treated by 32 P administered intramusculary as sodium orthophosphate in a single dose of 333 MBq per kilogram of body weight. Blood samples was taken from the wing vein on day 1, 3, 5, 7 and 10 after administration of 32 P. Alpha amylase activity and glucose concentration were determined spectrophotometrically using kits produced by 'Radonja', Sisak. Alpha amylase activity was decreased and glucose concentration was increased during investigated period. Yet, the further investigations are needed to find out whether these two parameters can be used for early diagnosis of injury in chicken organism by ionizing radiation. (author)

  18. Impact of ICRH on the measurement of fusion alphas by collective Thomson scattering in ITER

    DEFF Research Database (Denmark)

    Salewski, Mirko; Eriksson, L.-G.; Bindslev, Henrik

    2009-01-01

    , corresponding to an off-axis resonance. The sensitivities of the results to the He-3 concentration (0.1-4%) and the heating power (20-40 MW) are considered. Fusion born alphas dominate the total CTS signal for large Doppler shifts of the scattered radiation. The tritons generate a negligible fraction......Collective Thomson scattering (CTS) has been proposed for measuring the phase space distributions of confined fast ion populations in ITER plasmas. This study determines the impact of fast ions accelerated by ion cyclotron resonance heating (ICRH) on the ability of CTS to diagnose fusion alphas...... perpendicular velocities, it may be difficult to draw conclusions about the physics of alpha particles alone by CTS. With this exception, the CTS diagnostic can reveal the physics of the fusion alphas in ITER even under the presence of fast ions due to ICRH....

  19. Assessment of alpha radioactivity in Indian tobacco leaf-a detailed study with SSNTD

    International Nuclear Information System (INIS)

    Ghosh, Dipak; Deb, Argha; Sengupta, Rosalima; Patra, K.K.; Halder, S.; Maiti, S.

    2009-01-01

    People who inhale tobacco smoke are exposed to higher concentrations of radioactivity since tobacco contains polonium ( 210 Po) and lead ( 210 Pb) both of which are radioactive elements of radon decay series. Among these 210 Po emits damaging type of radiation-alpha radiation is 1000 times more carcinogenic than gamma radiation (DiFranza and Winters, 1982). It generates the localized radiation dose and the health of common people gets affected seriously. In view of this a detail measurement of radioactivity of tobacco leaf is essential. This paper presents a detail investigation on the measurement of alpha radioactivity in raw tobacco leaves, in a few commonly used Indian brand cigarettes and in packed chewing tobacco materials with solid state nuclear track detector (SSNTD). The study reveals the presence of pronounced alpha activity in cigarette tobacco and chewing tobacco samples ranging from 60-75 mBq/gm and 60- 75 mBq/gm. The alpha activity value is comparatively lower in raw tobacco leaves (9-50 mBq/gm). The annual committed effective dose of the smokers of these branded cigarettes has estimated to be 50-700 (μSv/y), whereas the effective dose value in raw tobacco leaves and chewing tobacco samples is 54-201 μSv/y and 230-290 μSv/y, respectively which are within the range found in cigarette samples. (author)

  20. Parameter-free calculation of K alpha chemical shifts for Al, Si, and Ge oxides

    DEFF Research Database (Denmark)

    Lægsgaard, Jesper

    2001-01-01

    The chemical shifts of the K alpha radiation line from Al, Si, and Ge ions between their elemental and oxide forms are calculated within the framework of density functional theory using ultrasoft pseudopotentials. It is demonstrated that this theoretical approach yields quantitatively accurate...

  1. A CO2 Laser Thomson Scattering Diagnostic For The Measurement Of Fusion Product Alpha Particles

    Science.gov (United States)

    Richards, R. K.; Bennett, C. A.; Fletcher, L. K.; Hunter, H. T.; Hutchinson, D. P.

    1988-11-01

    A Thomson scattering diagnostic for measuring the alpha particle velocity distribution is described. Calculations of scattering are made for a CIT type plasma using available CO2 laser and heterodyne technology. Tests of a long pulse CO2 laser, multichannel heterodyne detector, and an absorption cell for stray laser radiation are presented.

  2. Tensile behavior of orthorhombic alpha ''-titanium alloy studied by in situ X-ray diffraction

    DEFF Research Database (Denmark)

    Wang, X.D.; Lou, H.B.; Ståhl, Kenny

    2010-01-01

    The tensile behavior of a Ti-11%Zr-14%Nb-10%Sn alloy with pure orthorhombic alpha '' phase was studied by in situ X-ray diffraction using synchrotron radiation. It is found that no phase transformation happens during the whole tensile process. The "double-yielding" platforms of this alloy...

  3. Alpha emitters activity measurement using the defined solid angle method

    International Nuclear Information System (INIS)

    Blanchis, P.

    1983-01-01

    The defined solid angle counting method can reach a very high accuracy, specially for heavy ions as alpha particles emitted by a radioactive source. The activity measurement of such sources with a relative uncertainty of the order of 0.01% is investigated. Such an accuracy is available only under suitable conditions: the radiation emitted by the source must be isotropic and all the particles emitted in the effective solid angle must be detected. The efficiency detection value must be equal to unity and phenomena such as absorption or scattering must be null. It is shown that corrections often become necessary. All parameters which can influence the measurements are studied [fr

  4. Automation of a measurement systems of waste drum alpha activity

    International Nuclear Information System (INIS)

    Labarre, S.; Bardy, N.

    1985-10-01

    The alpha radiator activity in the two-hundred liter waste drums is found by an IN96, computerized analyzer of the society Intertechnique, from data delivered by a gamma detector (GeHP) and by neutron detection blocks (He counter). This computerized analyzer manages not only the drum rotation and position in front of the detector, but also the experimental data monitoring and their processing from specific programs (background noise, calibration, drum measurements). Thanks to this automation, the measurement number and their reliability are optimized [fr

  5. Interferon Alpha in Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Timothy B. Niewold

    2010-01-01

    Full Text Available The pleiotropic cytokine interferon alpha is involved in multiple aspects of lupus etiology and pathogenesis. Interferon alpha is important under normal circumstances for antiviral responses and immune activation. However, heightened levels of serum interferon alpha and expression of interferon response genes are common in lupus patients. Lupus-associated autoantibodies can drive the production of interferon alpha and heightened levels of interferon interfere with immune regulation. Several genes in the pathways leading to interferon production or signaling are associated with risk for lupus. Clinical and cellular manifestations of excess interferon alpha in lupus combined with the genetic risk factors associated with interferon make this cytokine a rare bridge between genetic risk and phenotypic effects. Interferon alpha influences the clinical picture of lupus and may represent a therapeutic target. This paper provides an overview of the cellular, genetic, and clinical aspects of interferon alpha in lupus.

  6. Novel alpha-mannosidase inhibitors; Nye alfa-mannosidaseinhibitorer

    Energy Technology Data Exchange (ETDEWEB)

    Farr, R.A.; Kang, M.S.; Peet, N.P.; Sunkara, S.P.

    1997-05-20

    [4S-(4{alpha}, 4a{beta}, 6{alpha}, 7{alpha}, 7a{alpha})]-Octahydro-1H-1-pyridine-4,5,6,7-tetrols and [4R-(4{alpha}, 4a{alpha}, 5{alpha}, 6{beta}, 7{beta}, 7a{beta})]-octahydro-1H-1-pyridine-4,5,6,7-tetrols are useful inhibitors of alpha-mannosidase and are useful immunostimulants, chemoprotective and radioprotective agents and antimetastatic agents.

  7. A novel method for alpha dosimetry using peeled-off Gafchromic EBT3 films

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kwang-Ho; Kim, Eun-Hee [Seoul National University, Seoul (Korea, Republic of)

    2016-10-15

    One can estimate dose imposed to film by measuring the optical density of film. EBT3 film has been used in dose measurement for photon, proton, and electron beams but not for alpha particles. Both sides of diacetylene monomer layer are covered with 100 μm-thick polyester coating layers, through which alpha particles even at several MeV cannot penetrate. A recent study demonstrated the use of EBT3 film in alpha dosimetry by peeling off one side of polyester coating layer. Their study did not inform the reliability of measurement using the peeled-off films. In this study, we evaluated the feasibility of EBT3 film as a substitute for conventional alpha dosimeters and checked the uncertainty of dose measurements obtained with peeled-off EBT3 films. We also applied this film dosimeter to measuring of the fluence distribution at cell targets in a culture dish set in the alpha irradiation chamber of the Radiation Bioengineering Laboratory (RadBio Lab) at Seoul National University (SNU). In this work, we confirmed the feasibility of using Gafchromic EBT3 films for alpha dosimetry. The peeled-off EBT3 films can make a convenient alpha dosimeter by carrying an uncertainty less than 9 %.

  8. Evolución de la inmunología e influencia en los trasplantes de órganos

    OpenAIRE

    Carretero Vegas, Luz María

    2012-01-01

    Se profundiza en el conocimiento sobre los mecanismos del sistema inmunológico y la evolución histórica de los mismos para conocer la influencia de la inmunología en los trasplantes y las medidas preventivas más adecuadas para evitar las complicaciones

  9. Activator protein 2alpha mediates parathyroid TGF-alpha self-induction in secondary hyperparathyroidism.

    Science.gov (United States)

    Arcidiacono, Maria Vittoria; Cozzolino, Mario; Spiegel, Noah; Tokumoto, Masanori; Yang, Jing; Lu, Yan; Sato, Tetsuhiko; Lomonte, Carlo; Basile, Carlo; Slatopolsky, Eduardo; Dusso, Adriana S

    2008-10-01

    In secondary hyperparathyroidism, enhanced expression of TGF-alpha in the parathyroid leads to its own upregulation, generating a feed-forward loop for TGF-alpha activation of its receptor, EGFR receptor (EGFR), which promotes parathyroid hyperplasia. These studies examined the role of activator protein 2alpha (AP2), an inducer of TGF-alpha gene transcription, in the upregulation of parathyroid TGF-alpha in secondary hyperparathyroidism. In rat and human secondary hyperparathyroidism, parathyroid AP2 expression strongly correlated with TGF-alpha levels and with the rate of parathyroid growth, as expected. Furthermore, the increases in rat parathyroid content of AP2 and its binding to a consensus AP2 DNA sequence preceded the increase in TGF-alpha induced by high dietary phosphate. More significant, in A431 cells, which provide a model of enhanced TGF-alpha and TGF-alpha self-induction, mutating the core AP2 site of the human TGF-alpha promoter markedly impaired promoter activity induced by endogenous or exogenous TGF-alpha. Important for therapy, in five-sixths nephrectomized rats fed high-phosphate diets, inhibition of parathyroid TGF-alpha self-induction using erlotinib, a highly specific inhibitor of TGF-alpha/EGFR-driven signals, reduced AP2 expression dosage dependently. This suggests that the increases in parathyroid AP2 occur downstream of EGFR activation by TGF-alpha and are required for TGF-alpha self-induction. Indeed, in A431 cells, erlotinib inhibition of TGF-alpha self-induction caused parallel reductions in AP2 expression and nuclear localization, as well as TGF-alpha mRNA and protein levels. In summary, increased AP2 expression and transcriptional activity at the TGF-alpha promoter determine the severity of the hyperplasia driven by parathyroid TGF-alpha self-upregulation in secondary hyperparathyroidism.

  10. Gemstone enhancement by radiation treatment

    International Nuclear Information System (INIS)

    Desai, Shripal N.

    1998-01-01

    Since the discovery of radioactivity, investigations on the effects of atomic rays on precious stones began and Crookes established that alpha rays from radium produced green colour in diamonds. Gamma rays, x-rays, electrons, neutrons, protons etc. are effective in producing colour in precious stone like topaz and corundum. Some of these also produce considerable amount of radioactivity which is not acceptable if the radioactivity exceeds permissible limits. Colour enhancement by radiation treatment, different radiations, safety of irradiated gem stones and market related aspects are discussed. (author)

  11. La influencia de la cultura política de la Revolución Francesa en los liberalismos europeos (1789-1848)

    OpenAIRE

    López Alcañiz, Vladimir

    2006-01-01

    Conferències impartides en el curs de doctorat La influencia de la cultura política de la Revolución Francesa en los liberalismos europeos (1789-1848). Conferencias del curso de doctorado La influencia de la cultura política de la Revolución Francesa en los liberalismos europeos (1789-1848). Seminar postgraduate courses La influencia de la cultura política de la Revolución Francesa en los liberalismos europeos (1789-1848).

  12. Radiation protection

    CERN Multimedia

    CERN. Geneva

    2001-01-01

    This will be a simple explanation of the reasons why CERN has to be careful about radiation protections issues, a practical guide on how to recognize radiation dangers, the monitoring systems that make sure radiation levels are well tolerable norms, and a quick summary of what radiation levels mean in terms of personal risk.

  13. Alpha particle studies during JET DT experiments

    International Nuclear Information System (INIS)

    1999-01-01

    The 1997 DT experiment (DTE1) at the Joint European Torus included studies of the behaviour of alpha particles in high temperature plasmas. Clear alpha particle heating was observed in a series of otherwise similar 10MW hot-ion H-modes by scanning the DT mixture from 0%T to 93%T. Maxima in central temperature and energy content were obtained which corresponded with the maximum in fusion yield. Alfven Eigenmodes (AEs) have been detected in JET, driven by NBI or ICRH fast ions. However, in agreement with theory, no AE activity was observed in DT plasmas which could be attributed to alpha particle drive, except in the afterglow of some Optimised Shear pulses. Ion Cyclotron Emission (ICE) was detected at harmonics of the alpha particle cyclotron frequency at the outer edge of the plasma. The ICE is interpreted as being close to magnetoacoustic cyclotron instability, driven by inverted alpha distributions at the plasma edge. The high-energy neutral particle spectra showed features, which are ascribed to a mixture of alphas, neutralised by helium-like impurities, and deuterons, born from elastic collisions with alpha particles and neutralised by hydrogen-like impurities. The results of all these studies are consistent with classical alpha particle trapping and slowing-down. Future DT experiments will aim to increase alpha particle pressure, so interactions with plasma instabilities can be studied. The measurement of knock-on neutral triton spectra offers a clean way to determine confined alpha densities in these future experiments. (author)

  14. Alpha particle studies during JET DT experiments

    International Nuclear Information System (INIS)

    2001-01-01

    The 1997 DT experiment (DTE1) at the Joint European Torus included studies of the behaviour of alpha particles in high temperature plasmas. Clear alpha particle heating was observed in a series of otherwise similar 10MW hot-ion H-modes by scanning the DT mixture from 0%T to 93%T. Maxima in central temperature and energy content were obtained which corresponded with the maximum in fusion yield. Alfven Eigenmodes (AEs) have been detected in JET, driven by NBI or ICRH fast ions. However, in agreement with theory, no AE activity was observed in DT plasmas which could be attributed to alpha particle drive, except in the afterglow of some Optimised Shear pulses. Ion Cyclotron Emission (ICE) was detected at harmonics of the alpha particle cyclotron frequency at the outer edge of the plasma. The ICE is interpreted as being close to magnetoacoustic cyclotron instability, driven by inverted alpha distributions at the plasma edge. The high-energy neutral particle spectra showed features, which are ascribed to a mixture of alphas, neutralised by helium-like impurities, and deuterons, born from elastic collisions with alpha particles and neutralised by hydrogen-like impurities. The results of all these studies are consistent with classical alpha particle trapping and slowing-down. Future DT experiments will aim to increase alpha particle pressure, so interactions with plasma instabilities can be studied. The measurement of knock-on neutral triton spectra offers a clean way to determine confined alpha densities in these future experiments. (author)

  15. The Alpha Magnetic Spectrometer (AMS)

    CERN Document Server

    Alcaraz, J; Ambrosi, G; Anderhub, H; Ao, L; Arefev, A; Azzarello, P; Babucci, E; Baldini, L; Basile, M; Barancourt, D; Barão, F; Barbier, G; Barreira, G; Battiston, R; Becker, R; Becker, U; Bellagamba, L; Bene, P; Berdugo, J; Berges, P; Bertucci, B; Biland, A; Bizzaglia, S; Blasko, S; Bölla, G; Boschini, M; Bourquin, Maurice; Brocco, L; Bruni, G; Buénerd, M; Burger, J D; Burger, W J; Cai, X D; Camps, C; Cannarsa, P; Capell, M; Casadei, D; Casaus, J; Castellini, G; Cecchi, C; Chang, Y H; Chen, H F; Chen, H S; Chen, Z G; Chernoplekov, N A; Tzi Hong Chiueh; Chuang, Y L; Cindolo, F; Commichau, V; Contin, A; Crespo, P; Cristinziani, M; Cunha, J P D; Dai, T S; Deus, J D; Dinu, N; Djambazov, L; Dantone, I; Dong, Z R; Emonet, P; Engelberg, J; Eppling, F J; Eronen, T; Esposito, G; Extermann, P; Favier, Jean; Fiandrini, E; Fisher, P H; Flügge, G; Fouque, N; Galaktionov, Yu; Gervasi, M; Giusti, P; Grandi, D; Grimm, O; Gu, W Q; Hangarter, K; Hasan, A; Hermel, V; Hofer, H; Huang, M A; Hungerford, W; Ionica, M; Ionica, R; Jongmanns, M; Karlamaa, K; Karpinski, W; Kenney, G; Kenny, J; Kim, W; Klimentov, A; Kossakowski, R; Koutsenko, V F; Kraeber, M; Laborie, G; Laitinen, T; Lamanna, G; Laurenti, G; Lebedev, A; Lee, S C; Levi, G; Levchenko, P M; Liu, C L; Liu, H T; Lopes, I; Lu, G; Lü, Y S; Lübelsmeyer, K; Luckey, D; Lustermann, W; Maña, C; Margotti, A; Mayet, F; McNeil, R R; Meillon, B; Menichelli, M; Mihul, A; Mourao, A; Mujunen, A; Palmonari, F; Papi, A; Park, I H; Pauluzzi, M; Pauss, Felicitas; Perrin, E; Pesci, A; Pevsner, A; Pimenta, M; Plyaskin, V; Pozhidaev, V; Postolache, V; Produit, N; Rancoita, P G; Rapin, D; Raupach, F; Ren, D; Ren, Z; Ribordy, M; Richeux, J P; Riihonen, E; Ritakari, J; Röser, U; Roissin, C; Sagdeev, R; Sartorelli, G; Schwering, G; Scolieri, G; Seo, E S; Shoutko, V; Shoumilov, E; Siedling, R; Son, D; Song, T; Steuer, M; Sun, G S; Suter, H; Tang, X W; Ting, Samuel C C; Ting, S M; Tornikoski, M; Torsti, J; Ulbricht, J; Urpo, S; Usoskin, I; Valtonen, E; Vandenhirtz, J; Velcea, F; Velikhov, E P; Verlaat, B; Vetlitskii, I; Vezzu, F; Vialle, J P; Viertel, Gert M; Vitè, Davide F; Gunten, H V; Wallraff, W; Wang, B C; Wang, J Z; Wang, Y H; Wiik, K; Williams, C; Wu, S X; Xia, P C; Yan, J L; Yan, L G; Yang, C G; Yang, M; Ye, S W; Yeh, P; Xu, Z Z; Zhang, H Y; Zhang, Z P; Zhao, D X; Zhu, G Y; Zhu, W Z; Zhuang, H L; Zichichi, A; Zimmermann, B

    2002-01-01

    The Alpha Magnetic Spectrometer (AMS) is a large acceptance (0.65 sr m sup 2) detector designed to operate in the International Space Station (ISS) for three years. The purposes of the experiment are to search for cosmic antimatter and dark matter and to study the composition and energy spectrum of the primary cosmic rays. A 'scaled-down' version has been flown on the Space Shuttle Discovery for 10 days in June 1998. The complete AMS is programmed for installation on the ISS in October 2003 for an operational period of 3 yr. This contribution reports on the experimental configuration that will be installed on the ISS.

  16. Targeted alpha therapy for cancer

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Barry J [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Raja, Chand [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Rizvi, Syed [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Li Yong [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Tsui, Wendy [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Zhang, David [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Song, Emma [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Qu, C F [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Kearsley, John [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Graham, Peter [Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray St, Kogarah 2217, NSW (Australia); Thompson, John [Sydney Melanoma Unit, Royal Prince Alfred Hospital, Camperdown 2050 NSW (Australia)

    2004-08-21

    Targeted alpha therapy (TAT) offers the potential to inhibit the growth of micrometastases by selectively killing isolated and preangiogenic clusters of cancer cells. The practicality and efficacy of TAT is tested by in vitro and in vivo studies in melanoma, leukaemia, colorectal, breast and prostate cancers, and by a phase 1 trial of intralesional TAT for melanoma. The alpha-emitting radioisotope used is Bi-213, which is eluted from the Ac-225 generator and chelated to a cancer specific monoclonal antibody (mab) or protein (e.g. plasminogen activator inhibitor-2 PAI2) to form the alpha-conjugate (AC). Stable alpha-ACs have been produced which have been tested for specificity and cytotoxicity in vitro against melanoma (9.2.27 mab), leukaemia (WM60), colorectal (C30.6), breast (PAI2, herceptin), ovarian (PAI2, herceptin, C595), prostate (PAI2, J591) and pancreatic (PAI2, C595) cancers. Subcutaneous inoculation of 1-1.5 million human cancer cells into the flanks of nude mice causes tumours to grow in all mice. Tumour growth is compared for untreated controls, nonspecific AC and specific AC, for local (subcutaneous) and systemic (tail vein or intraperitoneal) injection models. The {sup 213}Bi-9.2.27 AC is injected into secondary skin melanomas in stage 4 patients in a dose escalation study to determine the effective tolerance dose, and to measure kinematics to obtain the equivalent dose to organs. In vitro studies show that TAT is one to two orders of magnitude more cytotoxic to targeted cells than non-specific ACs, specific beta emitting conjugates or free isotopes. In vivo local TAT at 2 days post-inoculation completely prevents tumour formation for all cancers tested so far. Intra-lesional TAT can completely regress advanced sc melanoma but is less successful for breast and prostate cancers. Systemic TAT inhibits the growth of sc melanoma xenografts and gives almost complete control of breast and prostate cancer tumour growth. Intralesional doses up to 450 {mu

  17. The Alpha Magnetic Spectrometer (ams)

    Science.gov (United States)

    Ionica, Maria

    2004-01-01

    The Alpha Magnetic Spectrometer (AMS), once installed on the International Space Station will provide precise measurements of the cosmic ray spectra up to TeV energy range, and will search for cosmological antimatter and missing matter. A prototype version of the detector was operated successfully on the space shuttle Discovery in June 1998 (STS-91). Here we briefly report on the design of the AMS apparatus and present the results of the measurements of the fluxes of proton, electron, positron and helium from the STS-91 flight.

  18. Crossing symmetry in Alpha space

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    The conformal bootstrap program aims to catalog all conformal field theories (second-order phase transitions) in D dimensions. Despite its ambitious scope much progress has been made over the past decade, e.g. in computing critical exponents for the 3D O(N) models to high precision. At this stage, analytic methods to explore the CFT landscape are not as well developed. In this talk I will describe a new mathematical framework for the bootstrap known as "alpha space", which reduces crossing symmetry to a set of integral equations. Based on arXiv:1702.08471 (with Balt van Rees) and arXiv:1703.08159.

  19. The Alpha Magnetic Spectrometer (AMS)

    International Nuclear Information System (INIS)

    Alcaraz, J.; Alpat, B.; Ambrosi, G.; Anderhub, H.; Ao, L.; Arefiev, A.; Azzarello, P.; Babucci, E.; Baldini, L.; Basile, M.; Barancourt, D.; Barao, F.; Barbier, G.; Barreira, G.; Battiston, R.; Becker, R.; Becker, U.; Bellagamba, L.; Bene, P.; Berdugo, J.; Berges, P.; Bertucci, B.; Biland, A.; Bizzaglia, S.; Blasko, S.; Boella, G.; Boschini, M.; Bourquin, M.; Brocco, L.; Bruni, G.; Buenerd, M.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Camps, C.; Cannarsa, P.; Capell, M.; Casadei, D.; Casaus, J.; Castellini, G.; Cecchi, C.; Chang, Y.H.; Chen, H.F.; Chen, H.S.; Chen, Z.G.; Chernoplekov, N.A.; Chiueh, T.H.; Chuang, Y.L.; Cindolo, F.; Commichau, V.; Contin, A.; Crespo, P.; Cristinziani, M.; Cunha, J.P. da; Dai, T.S.; Deus, J.D.; Dinu, N.; Djambazov, L.; DAntone, I.; Dong, Z.R.; Emonet, P.; Engelberg, J.; Eppling, F.J.; Eronen, T.; Esposito, G.; Extermann, P.; Favier, J.; Fiandrini, E.; Fisher, P.H.; Fluegge, G.; Fouque, N.; Galaktionov, Yu.; Gervasi, M.; Giusti, P.; Grandi, D.; Grimm, O.; Gu, W.Q.; Hangarter, K.; Hasan, A.; Hermel, V.; Hofer, H.; Huang, M.A.; Hungerford, W.; Ionica, M.; Ionica, R.; Jongmanns, M.; Karlamaa, K.; Karpinski, W.; Kenney, G.; Kenny, J.; Kim, W.; Klimentov, A.; Kossakowski, R.; Koutsenko, V.; Kraeber, M.; Laborie, G.; Laitinen, T.; Lamanna, G.; Laurenti, G.; Lebedev, A.; Lee, S.C.; Levi, G.; Levtchenko, P.; Liu, C.L.; Liu, H.T.; Lopes, I.; Lu, G.; Lu, Y.S.; Luebelsmeyer, K.; Luckey, D.; Lustermann, W.; Mana, C.; Margotti, A.; Mayet, F.; McNeil, R.R.; Meillon, B.; Menichelli, M.; Mihul, A.; Mourao, A.; Mujunen, A.; Palmonari, F.; Papi, A.; Park, I.H.; Pauluzzi, M.; Pauss, F.; Perrin, E.; Pesci, A.; Pevsner, A.; Pimenta, M.; Plyaskin, V.; Pojidaev, V.; Postolache, V.; Produit, N.; Rancoita, P.G.; Rapin, D.; Raupach, F.; Ren, D.; Ren, Z.; Ribordy, M.; Richeux, J.P.; Riihonen, E.; Ritakari, J.; Roeser, U.; Roissin, C.; Sagdeev, R.; Sartorelli, G.; Schultz von Dratzig, A.; Schwering, G.; Scolieri, G.; Seo, E.S.; Shoutko, V.; Shoumilov, E.; Siedling, R.; Son, D.; Song, T.; Steuer, M.; Sun, G.S.; Suter, H.; Tang, X.W.; Ting, S.C.C.Samuel C.C.; Ting, S.M.; Tornikoski, M.; Torsti, J.; Tr umper, J.; Ulbricht, J.; Urpo, S.; Usoskin, I.; Valtonen, E.; Vandenhirtz, J.; Velcea, F.; Velikhov, E.; Verlaat, B.; Vetlitsky, I.; Vezzu, F.; Vialle, J.P.; Viertel, G.; Vite, D.; Gunten, H. Von; Wicki, S.W.S. Waldmeier; Wallraff, W.; Wang, B.C.; Wang, J.Z.; Wang, Y.H.; Wiik, K.; Williams, C.; Wu, S.X.; Xia, P.C.; Yan, J.L.; Yan, L.G.; Yang, C.G.; Yang, M.; Ye, S.W.; Yeh, P.; Xu, Z.Z.; Zhang, H.Y.; Zhang, Z.P.; Zhao, D.X.; Zhu, G.Y.; Zhu, W.Z.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.

    2002-01-01

    The Alpha Magnetic Spectrometer (AMS) is a large acceptance (0.65 sr m 2 ) detector designed to operate in the International Space Station (ISS) for three years. The purposes of the experiment are to search for cosmic antimatter and dark matter and to study the composition and energy spectrum of the primary cosmic rays. A 'scaled-down' version has been flown on the Space Shuttle Discovery for 10 days in June 1998. The complete AMS is programmed for installation on the ISS in October 2003 for an operational period of 3 yr. This contribution reports on the experimental configuration that will be installed on the ISS

  20. Hydrocarbon photochemistry and Lyman alpha albedo of Jupiter

    Science.gov (United States)

    Yung, Y. L.; Strobel, D. F.

    1980-01-01

    A combined study of hydrocarbon and atomic hydrogen photochemistry is made to calculate self-consistently the L alpha albedo of Jupiter. It is shown that the L alpha emissions observed by Voyagers I and II can be explained by resonance scattering of sunlight. Precipitation of energetic particles from the magnetosphere can provide the large required source of atomic hydrogen, although the contribution of direct particle excitation to the disk-averaged brightness is insignificant. The variability of the L alpha brightness inferred from many observations in recent years is examined. The large difference in the brightness of the He 584 A resonance line observed by Pioneer and Voyager is briefly discussed. Driving the photochemistry by solar ultraviolet radiation alone yields a maximum mixing ratio of C2H6 + C2H2 at 0.01 atm of about 4 x 10 to the -6th. The possibility of additional CH4 dissociation from precipitation of magnetospheric particles is discussed. The photochemistry of C2H2 and C2H3 is sufficiently uncertain not to permit accurate calculations of their densities and the ratio C2H6/C2H2.

  1. Precision measurements on trapped antihydrogen in the ALPHA experiment

    Science.gov (United States)

    Eriksson, S.

    2018-03-01

    Both the 1S-2S transition and the ground state hyperfine spectrum have been observed in trapped antihydrogen. The former constitutes the first observation of resonant interaction of light with an anti-atom, and the latter is the first detailed measurement of a spectral feature in antihydrogen. Owing to the narrow intrinsic linewidth of the 1S-2S transition and use of two-photon laser excitation, the transition energy can be precisely determined in both hydrogen and antihydrogen, allowing a direct comparison as a test of fundamental symmetry. The result is consistent with CPT invariance at a relative precision of around 2×10-10. This constitutes the most precise measurement of a property of antihydrogen. The hyperfine spectrum of antihydrogen is determined to a relative uncertainty of 4×10-4. The excited state and the hyperfine spectroscopy techniques currently both show sensitivity at the few 100 kHz level on the absolute scale. Here, the most recent work of the ALPHA collaboration on precision spectroscopy of antihydrogen is presented together with an outlook on improving the precision of measurements involving lasers and microwave radiation. Prospects of measuring the Lamb shift and determining the antiproton charge radius in trapped antihydrogen in the ALPHA apparatus are presented. Future perspectives of precision measurements of trapped antihydrogen in the ALPHA apparatus when the ELENA facility becomes available to experiments at CERN are discussed. This article is part of the Theo Murphy meeting issue `Antiproton physics in the ELENA era'.

  2. Radiation Basics

    Science.gov (United States)

    ... such as hydrogen-3 ( tritium ), carbon-14 and strontium-90 . Beta particles are more penetrating than alpha ... Waste, and Cleanup Lead Mold Pesticides Radon Science Water A-Z Index Laws & Regulations By Business Sector ...

  3. Alpha radioactivity in Indian cement samples

    International Nuclear Information System (INIS)

    Nain, M.; Chauhan, R. P.; Chakarvarti, S. K.

    2006-01-01

    The essential constituents of radioactive and each of cements like lime, silica and alumina are derived from earth's crust in which radioactive elements like uranium, thorium etc are also present in varying amounts almost everywhere. These two elements are considered as the parent elements of uranium and thorium radioactive decay series in which radon and thoron are produced respectively as decay products. In the present study the samples of ordinary Portland cement , Portland pozzolana cement and some other cementious finishing materials like white cement, Plaster of Paris , cement putty etc were collected and analysed for radium and radon concentrations along with radon exhalation rates. Materials and Methods: Alpha sensitive LR-115 Type II plastic track detectors commonly known as S olid State Nuclear Track Detectors w ere used to measure the radium and radon concentration. The alpha particles emitted from the radon causes the radiation damaged tracks. The Chemical etching in NaOH at 60 C for about 90 minutes was done to reveal these latent tracks, which were then scanned and counted by an optical microscope of suitable magnification. By calculating the track density of registered tracks, the radon and radium concentrations along with exhalation rate of radon, were determined using required formulae. Results: The radon and radium concentration in various brands of cements found to vary from 333±9.9 to 506±13.3 Bq m-3 and from 3.7±0.1 to 5.6±0.2 Bq k g-1 while in various cementious finishing materials used in the construction, these were found to vary from 378±19.7 to 550±9.8 Bq m-3 and from 4.2±0.2 to 6.1±0.1 Bq Kg-1, respectively. Based on the data the mass and surface exhalation rates were also calculated Conclusion: The measurements indicate that there is marginal variation of the concentration of radium and radon in various brands of cements in India with lower levels in the cement samples having red oxide and higher levels in fly ash based cement

  4. Influencia del rol de género en la conducta sexual de riesgo en adolescentes universitarios Influence of gender role on the sexual behavior of university students

    Directory of Open Access Journals (Sweden)

    Yesica Yolanda Rangel Flores

    2010-12-01

    Full Text Available Objetivo: Analizar el comportamiento sexual de estudiantes universitarios y la influencia del género en la caracterización del mismo. Material y métodos: Estudio transversal, descriptivo y correlacional efectuado de Enero a Junio de 2009. Muestra probabilística estratificada de 250 estudiantes de cinco programas de Licenciatura. Aplicación de instrumento creado ex profeso, validado mediante expertos y con una confiabilidad comprobada de .78 mediante Alpha de Cronbach. Estadística descriptiva e inferencial a través de SPSS 17.0. Resultados: 56.6% de la población refiere vida sexual activa, con mayor ejercicio en los hombres (x²=13.272 p=.01. Hombres más que mujeres y con una diferencia significativa refirieron tener relaciones sexuales con más de una persona en un mismo periodo de tiempo (Tb=.730 p=.000, tener encuentros sexuales casuales (Tb=.294 p=.000. La utilización del condón se refiere como habitual más en hombres (86.8% que en mujeres (50% (V=.377 p=.002. Conclusiones: Se identifican conductas de riesgo tanto en hombres como en mujeres, en ambos casos íntimamente ligados a las representaciones sociales de género.Objective: Analyze the sexual behavior of University students and the influence of gender in the characterization of the referred behavior. Material and methods: Transverse, descriptive and correlational study which was carried out from January to June 2009. Stratified probabistical sample of 250 students from five bachelor degree programs. Application of an instrument created on purpose, validated by experts with a proven reliability of .78 using Cronbach Alpha. Descriptive statistical s and inferential using SPSS 17.0. Results: 56.6% of the population referred having an active sex life, with greater exercise in men (x² = 13. 272 p =. 01. Men more than women and with a significant difference, men spoke of having sex with more than one person in a same period of time (Tb =. 730 p =. 000, having casual sexual

  5. First Results of Using a UVTron Flame Sensor to Detect Alpha-Induced Air Fluorescence in the UVC Wavelength Range

    Directory of Open Access Journals (Sweden)

    Anita J. Crompton

    2017-11-01

    Full Text Available In this work, a robust stand-off alpha detection method using the secondary effects of alpha radiation has been sought. Alpha particles ionise the surrounding atmosphere as they travel. Fluorescence photons produced as a consequence of this can be used to detect the source of the alpha emissions. This paper details experiments carried out to detect this fluorescence, with the focus on photons in the ultraviolet C (UVC wavelength range (180–280 nm. A detector, UVTron R9533 (Hamamatsu, 325-6, Sunayama-cho, Naka-ku, Hamamatsu City, Shizuoka Pref., 430-8587, Japan, designed to detect the UVC emissions from flames for fire alarm purposes, was tested in various gas atmospheres with a 210Po alpha source to determine if this could provide an avenue for stand-off alpha detection. The results of the experiments show that this detector is capable of detecting alpha-induced air fluorescence in normal indoor lighting conditions, as the interference from daylight and artificial lighting is less influential on this detection system which operates below the UVA and UVB wavelength ranges (280–315 nm and 315–380 nm respectively. Assuming a standard 1 r 2 drop off in signal, the limit of detection in this configuration can be calculated to be approximately 240 mm, well beyond the range of alpha-particles in air, which indicates that this approach could have potential for stand-off alpha detection. The gas atmospheres tested produced an increase in the detector count, with xenon having the greatest effect with a measured 52% increase in the detector response in comparison to the detector response in an air atmosphere. This type of alpha detection system could be operated at a distance, where it would potentially provide a more cost effective, safer, and faster solution in comparison with traditional alpha detection methods to detect and characterise alpha contamination in nuclear decommissioning and security applications.

  6. First Results of Using a UVTron Flame Sensor to Detect Alpha-Induced Air Fluorescence in the UVC Wavelength Range.

    Science.gov (United States)

    Crompton, Anita J; Gamage, Kelum A A; Bell, Steven; Wilson, Andrew P; Jenkins, Alex; Trivedi, Divyesh

    2017-11-29

    In this work, a robust stand-off alpha detection method using the secondary effects of alpha radiation has been sought. Alpha particles ionise the surrounding atmosphere as they travel. Fluorescence photons produced as a consequence of this can be used to detect the source of the alpha emissions. This paper details experiments carried out to detect this fluorescence, with the focus on photons in the ultraviolet C (UVC) wavelength range (180-280 nm). A detector, UVTron R9533 (Hamamatsu, 325-6, Sunayama-cho, Naka-ku, Hamamatsu City, Shizuoka Pref., 430-8587, Japan), designed to detect the UVC emissions from flames for fire alarm purposes, was tested in various gas atmospheres with a 210 Po alpha source to determine if this could provide an avenue for stand-off alpha detection. The results of the experiments show that this detector is capable of detecting alpha-induced air fluorescence in normal indoor lighting conditions, as the interference from daylight and artificial lighting is less influential on this detection system which operates below the UVA and UVB wavelength ranges (280-315 nm and 315-380 nm respectively). Assuming a standard 1 r 2 drop off in signal, the limit of detection in this configuration can be calculated to be approximately 240 mm, well beyond the range of alpha-particles in air, which indicates that this approach could have potential for stand-off alpha detection. The gas atmospheres tested produced an increase in the detector count, with xenon having the greatest effect with a measured 52% increase in the detector response in comparison to the detector response in an air atmosphere. This type of alpha detection system could be operated at a distance, where it would potentially provide a more cost effective, safer, and faster solution in comparison with traditional alpha detection methods to detect and characterise alpha contamination in nuclear decommissioning and security applications.

  7. Spreadsheet design and validation for characteristic limits determination in gross alpha and beta measurement

    International Nuclear Information System (INIS)

    Prado, Rodrigo G.P. do; Dalmazio, Ilza

    2013-01-01

    The identification and detection of ionizing radiation are essential requisites of radiation protection. Gross alpha and beta measurements are widely applied as a screening method in radiological characterization, environmental monitoring and industrial applications. As in any other analytical technique, test performance depends on the quality of instrumental measurements and reliability of calculations. Characteristic limits refer to three specific statistics, namely, decision threshold, detection limit and confidence interval, which are fundamental to ensuring the quality of determinations. This work describes a way to calculate characteristic limits for measurements of gross alpha and beta activity applying spreadsheets. The approach used for determination of decision threshold, detection limit and limits of the confidence interval, the mathematical expressions of measurands and uncertainty followed standards guidelines. A succinct overview of this approach and examples are presented and spreadsheets were validated using specific software. Furthermore, these spreadsheets could be used as tool to instruct beginner users of methods for ionizing radiation measurements. (author)

  8. Computation of Cosmic Ray Ionization and Dose at Mars: a Comparison of HZETRN and Planetocosmics for Proton and Alpha Particles

    Science.gov (United States)

    Gronoff, Guillaume; Norman, Ryan B.; Mertens, Christopher J.

    2014-01-01

    The ability to evaluate the cosmic ray environment at Mars is of interest for future manned exploration. To support exploration, tools must be developed to accurately access the radiation environment in both free space and on planetary surfaces. The primary tool NASA uses to quantify radiation exposure behind shielding materials is the space radiation transport code, HZETRN. In order to build confidence in HZETRN, code benchmarking against Monte Carlo radiation transport codes is often used. This work compares the dose calculations at Mars by HZETRN and the Geant4 application Planetocosmics. The dose at ground and the energy deposited in the atmosphere by galactic cosmic ray protons and alpha particles has been calculated for the Curiosity landing conditions. In addition, this work has considered Solar Energetic Particle events, allowing for the comparison of varying input radiation environments. The results for protons and alpha particles show very good agreement between HZETRN and Planetocosmics.

  9. Entretenimiento, espiritualidad, familia y la influencia de pares universitarios en el consumo de drogas

    Directory of Open Access Journals (Sweden)

    Aydee Rivera de Parada

    2015-01-01

    Full Text Available El objetivo del estudio fue examinar la relación de los factores socio-culturales de familia, entretenimiento y espiritualidad y la influencia de pares y el consumo de drogas entre los estudiantes universitarios. Estudio es multicéntrico, con un diseño transversal, participaron 250 estudiantes de una universidad en San Salvador, El Salvador. Se realizaron análisis porcentuales, pruebas de asociación y correlación. Se encontró que los factores socioculturales de familia y espiritualidad podrían estar protegiendo ya que la mayoría 80% valoran positivamente estos dos valores. La mayoría de estudiantes consumen muy poco drogas ilícitas, marihuana 2%, cocaína 1% y anfetaminas 1.2%; pero consume más las drogas lícitas alcohol 42%, tabaco 21%.

  10. Influencia del yeso sobre la velocidad de hidratación del cemento portland

    Directory of Open Access Journals (Sweden)

    Yamaguchi, G.

    1961-12-01

    Full Text Available Not availablePara esclarecer la Influencia del yeso sobre el fraguado y endurecimiento del cemento, los autores estudiaron el grado de hidratación de los cuatro principales minerales del clínker de cemento Portland y el efecto del yeso sobre ellas. Haciendo uso del análisis cuantitativo de rayos X, se determinó la porción no hidratada. Simultáneamente, se determinaron los tiempos de fraguado y las resistencias. Los ensayos se llevaron a cabo sobre tres clínkeres sintéticos de diferentes composiciones y sobre dos clínkeres de cemento Portland comerciales.

  11. La Doctrina del Secondary Meaning, su influencia en los sistemas constitutivos de derechos marcarios.

    Directory of Open Access Journals (Sweden)

    Javier Romero Calero

    2009-06-01

    Full Text Available El presente trabajo aborda, teniendo como referencia la legislación cubana, la esencia de la doctrina del secondary meaning o distintividad sobrevenida, así como su influencia en el sistema constitutivo de derecho marcario, considerándose acertado el hecho de que el legislador nacional prevea en el articulado del decreto Ley 203 de marcas y otros signos distintivos de 2000, que dos de las prohibiciones absolutas establecidas en dicho cuerpo legal puedan ser convalidadas, por adquirir el signo, que ad initio fue denegado, aptitud distintiva con relación a los productos o servicios a los que se destina dado el uso de éste en el comercio, sin que esto entre en contradicción con el sistema constitutivo de adquisición de derechos que prevalece en el ordenamiento jurídico nacional.

  12. Influencia de curso pre cálculo en ecuaciones diferenciales y desarrollo de pensamiento variacional

    Directory of Open Access Journals (Sweden)

    Mawency Vergel Ortega

    2018-01-01

    Full Text Available La investigación sigue un enfoque cuantitativo con apoyo del enfoque cualitativo, descriptivo, diseño cuasi experimental. En esta investigación se plantearon los objetivos: estudiar si mejoran las competencias en pensamiento variacional y didácticas de los estudiantes con la utilización de curso precálculo utilizando plataforma virtual respecto a enseñanza tradicional; examinar la influencia en desarrollo del pensamiento matemático y su enseñanza; así como analizar qué tipología de alumnos obtiene mejores resultados en relación a su nivel de competencia digital. Se han obtenido los siguientes avances: el grupo experimental ha obtenido una mejora estadísticamente significativa de sus competencias interpretativas y de pensamiento matemático respecto al grupo control.

  13. La influencia del liderazgo sobre el aprendizaje. El papel mediador del contexto organizativo

    Directory of Open Access Journals (Sweden)

    Susana Pérez López

    2012-09-01

    Full Text Available En este trabajo se analiza la relación existente entre liderazgo y aprendizaje organizativo. Con apoyo en investigaciones previas, se plantea un modelo cuya premisa básica es que la relación entre ambos conceptos es directa e indirecta, en la medida en que el liderazgo influye sobre el contexto organizativo en que se desarrolla el aprendizaje. El presente modelo teórico ha sido contrastado empíricamente a partir de una muestra de 162 empresas españolas, confirmándose la influencia del liderazgo sobre la cultura organizativa y el desarrollo de las políticas de recursos humanos, factores que, a su vez, influyen sobre el aprendizaje. Sin embargo, la relación directa entre liderazgo y aprendizaje organizativo no se confirma. Las implicaciones del estudio, limitaciones y futuras líneas de investigación son discutidas en el trabajo.

  14. Influencia de variables psicológicas en el rendimiento de jugadores amateurs de golf

    Directory of Open Access Journals (Sweden)

    Susana Irazusta

    2006-01-01

    Full Text Available El propósito de la presente investigación es analizar las variaciones del estado de ánimo intracompetición en los jugadores amateurs de golf, así como analizar la influencia que tiene el grado de confianza y otras variables motivacionales en el resultado de la competición. Se realizó la investigación con un total de 296 jugadores y se pasaron los cuestionarios a cada jugador en tres momentos, antes, durante y después de la competición.Una vez analizados los datos se constató que existen grandes fluctuaciones en el estado de ánimo de los jugadores y que el resultado esperado sufre modificaciones a lo largo de la competición.

  15. Biophysical interpretation on the biological actions of radiations

    International Nuclear Information System (INIS)

    Nishiwaki, Yasushi

    1960-01-01

    It is known that nuclear radiations such as alpha, beta, gamma, x-rays and neutron, proton and other heavy ion beams have many different actions on living cells; as killing, delaying growth, abnormal cell divisions and various genetical mutations and chromosomal aberrations. This document describes the mechanisms and kinetics of biological effects of ionizing radiation

  16. Localized defects in radiation-damaged zircon

    Science.gov (United States)

    Rios; Malcherek; Salje; Domeneghetti

    2000-12-01

    The crystal structure of a radiation-damaged natural zircon, ZrSiO(4) (alpha-decay radiation dose is ca 1.8 x 10(18) alpha-decay events g(-1)), has been determined. The anisotropic unit-cell swelling observed in the early stages of the amorphization process (0.17% along the a axis and 0.62% along the c axis compared with the undamaged material) is a consequence of the anisotropy of the expansion of ZrO(8) polyhedra. Larger anisotropic displacement parameters were found for Zr and O atoms, indicating that the distortion produced by alpha particle-induced localized defects mainly affects the ZrO(8) unit. The overall shape of SiO(4) tetrahedra remains essentially undistorted, while Si-O bonds are found to lengthen by 0.43%.

  17. Influencia del medio familiar en niños con conductas agresivas

    Directory of Open Access Journals (Sweden)

    Nilo Valentín Noroño Morales

    2002-06-01

    Full Text Available Se realizó un estudio descriptivo, sobre la influencia del medio familiar en niños de 9 a 11 años, con conductas agresivas, evaluados y diagnosticados en el Departamento de Psicología del Policlínico " Dr. Tomás Romay"; la muestra estuvo conformada además, por los padres de estos niños. A todos ellos se les aplicó una serie de técnicas con el objetivo principal de describir las características del medio familiar y su influencia en las conductas agresivas de los infantes. Se concluyó en que como características del medio familiar predominaron las familias disfuncionales incompletas, con manifestaciones de agresividad, alcoholismo, mala integración social y familiar, rechazo hacia los hijos e irresponsabilidad en su cuidado y atención.A descriptive study of the influence of the family environment on children aged 9-11 years old, evaluated and diagnosed at the Psychology Department of "Dr Tomás Romay" polyclinics, was carried out. The children´s parents were also part of the sample. All of them were applied a series of techniques to find out the characteristics of the family environment and its influence on children´s aggressive behaviors. It was concluded that the predominant characteristics were uncompleted dysfunctional families with manifestations of aggressiveness, alcoholism, poor social and family integration, rejection to children and lack of responsibility in relation to their care and attention.

  18. Influencia del clima escolar y familiar en adolescentes, víctimas de ciberacoso

    Directory of Open Access Journals (Sweden)

    Jessica Ortega Barón

    2016-01-01

    Full Text Available El ciberacoso es un fenómeno de creciente preocupación social que afecta cada vez más a niños y adolescentes de todos los países desarrollados. A diferencia de la considerable literatura que hay sobre las relaciones entre el acoso escolar y el contexto familiar y escolar, todavía hay pocos trabajos sobre la influencia de estos entornos sociales en el problema del ciberacoso. Mediante una metodología cuantitativa, el objetivo principal del presente estudio fue analizar la influencia del contexto escolar y familiar en víctimas de ciberacoso. La muestra estuvo formada por 1.062 adolescentes (51,5% chicos y 48,5% chicas, de edades comprendidas entre los 12 y los 18 años (M=14,5; DT=1,62. Se establecieron tres grupos de contraste: cibervíctimas severas, cibervíctimas moderadas y no víctimas de ciberacoso. Los resultados del análisis de varianza indicaron que las cibervíctimas severas en comparación con las no víctimas puntúan significativamente más alto en conflicto familiar y obtienen puntuaciones más bajas en el resto de variables familiares (autoestima familiar, cohesión y expresividad, y variables escolares (implicación, afiliación y ayuda al profesor, consideradas en el estudio. Los análisis de regresión revelaron que la autoestima académica y familiar y algunas dimensiones del clima familiar y escolar predicen la cibervictimización en la adolescencia. Estos novedosos resultados muestran la importancia de incluir a la familia y a la escuela en los programas de prevención del ciberacoso.

  19. Solid state nuclear track detectors in the measurement of alpha to fission branching ratios of heavy actinides

    International Nuclear Information System (INIS)

    Pandey, A.K.; Sharma, R.C.; Padalkar, S.K.; Kalsi, P.C.; Iyer, R.H.

    1992-01-01

    A sequential etching procedure for revelation of alpha and fission tracks in CR-39 was developed and optimized. Using this technique alpha and fission tracks can be differentiated unambiguously because of significant differences in their sizes and etching times. This registration and revelation procedure for alpha and fission tracks may be used for the studies of half lives, alpha to fission branching ratios and identification of radionuclides based on their decay schemes. It has the added advantage that both alpha decay and fission events can be studied using one detector and hence uncertainties related to efficiency, registration geometry, registration times, amount of radionuclides etc can be eliminated or minimized. The effects of neutron, gamma and alpha radiations on the alpha and fission fragment tracks registration and revelation properties of CR-39 detectors [CR-39, CR-39 (DOP)] were also studied. The IR spectra were also studied to find out the nature of chemical changes produced by these radiations on CR-39. (author). 32 refs., 7 figs., 4 tabs

  20. Radiation polymerized hot melt pressure sensitive adhesives

    International Nuclear Information System (INIS)

    Pastor, S.D.; Skoultchi, M.M.

    1977-01-01

    Hot melt pressure sensitive adhesive compositions formed by copolymerizing at least one 3-(chlorinated aryloxy)-2-hydroxypropyl ester of an alpha, beta unsaturated carboxylic acid with acrylate based copolymerizable monomers, are described. The resultant ethylenically saturated prepolymer is heated to a temperature sufficient to render it fluid and flowable. This composition is coated onto a substrate and exposed to ultraviolet radiation

  1. Quantum Estimates of Alpha Emitter Life Time

    Directory of Open Access Journals (Sweden)

    B. Santoso

    2006-01-01

    Full Text Available Quantum estimates of several alpha radioactive life time have been made using the probability of quantum tunneling through the nuclear potential barrier. It is assumed that for a given nucleus with mass number A and isotopic number Z, there exists an alpha particle moving freely back and forth in the nucleus with mass and isotopic numbers A -4 and Z-2. If the probability of penetrating the nuclear potential barrier is Τ, then after N times (N=1/Τ hitting the barrier an alpha particle is emitted. To obtain the elapsed time for emitting an alpha particle requires N times τ0, where τ0 is the time travel for alpha across the nuclear diameter, which is dependent on alpha energy. It is assumed here that this kinetic energy is the same as the emitted energy. The emitting alpha kinetic energies here are calculated by the difference of the masses of the parent and daughter nuclei and the alpha particles. They are in closed agreement with the experimental observations. While the alpha radioactive life time are not the same order of magnitudes but give the same linearity on the logarithmic scale as function of the inverse square root of energy.

  2. Sterically hindered C(alpha, alpha)-disubstituted alpha-amino acids: synthesis from alpha-nitroacetate and incorporation into peptides.

    Science.gov (United States)

    Fu, Y; Hammarström, L G; Miller, T J; Fronczek, F R; McLaughlin, M L; Hammer, R P

    2001-10-19

    The preparation of sterically hindered and polyfunctional C(alpha,alpha)-disubstituted alpha-amino acids (alpha alpha AAs) via alkylation of ethyl nitroacetate and transformation into derivatives ready for incorporation into peptides are described. Treatment of ethyl nitroacetate with N,N-diisopropylethylamine (DIEA) in the presence of a catalytic amount of tetraalkylammonium salt, followed by the addition of an activated alkyl halide or Michael acceptor, gives the doubly C-alkylated product in good to excellent yields. Selective nitro reduction with Zn in acetic acid or hydrogen over Raney Ni gives the corresponding amino ester that, upon saponification, can be protected with the fluorenylmethyloxycarbonyl (Fmoc) group. The first synthesis of an orthogonally protected, tetrafunctional C(alpha,alpha)-disubstituted analogue of aspartic acid, 2,2-bis(tert-butylcarboxymethyl)glycine (Bcmg), is described. Also, the sterically demanding C(alpha,alpha)-dibenzylglycine (Dbg) has been incorporated into a peptide using solid-phase synthesis. It was found that once sterically congested Dbg is at the peptide N-terminus, further chain extension becomes very difficult using uronium or phosphonium salts (PyAOP, PyAOP/HOAt, HATU). However, preformed amino acid symmetrical anhydride couples to N-terminal Dbg in almost quantitative yield in nonpolar solvent (dichloroethane-DMF, 9:1).

  3. Influencia de la actividad física y la alimentación equilibrada en la mejora de la calidad de vida /

    OpenAIRE

    Vidaurrazaga Dobaran, Andoni

    2013-01-01

    Se estudia la influencia que la actividad física tiene en la calidad de vida de las personas. Es de sobra conocido que vivir de forma saludable es beneficioso para la salud pero se trata de esclarecer qué entendemos por “vivir de forma saludable” y cuál puede ser su influencia en el mantenimiento y mejora de la calidad de vida de las personas

  4. Radiation Therapy

    Science.gov (United States)

    ... radiation may be external, from special machines, or internal, from radioactive substances that a doctor places inside your body. The type of radiation therapy you receive depends on many factors, including The ...

  5. Radiation safety

    International Nuclear Information System (INIS)

    Woods, D.A.

    1982-01-01

    Sections include: dose units, dose limits, dose rate, potential hazards of ionizing radiations, control of internal and external radiation exposure, personal dosemeters, monitoring programs and transport of radioactive material (packaging and shielding)

  6. Radiation Therapy

    Science.gov (United States)

    ... kill any cancer cells that remain. Lifetime Dose Limits There is a limit to the amount of radiation an area of ... total dose of radiation more quickly or to limit damage to healthy cells. Different ways of delivering ...

  7. Radiation Emergencies

    Science.gov (United States)

    ... amounts of radiation and could be caused by Dirty bombs - a mix of explosives with radioactive powder Fallout from a nuclear bomb Accidental release from a nuclear reactor or a nuclear weapons plant A lot of radiation over a short ...

  8. Report of a Technical Meeting on ''Alpha emitting radionuclides and radiopharmaceuticals for therapy''

    International Nuclear Information System (INIS)

    2013-01-01

    Considering the high potential of α-emitters for future development of radionuclide therapy, the International Atomic Energy Agency (IAEA) organized a Technical Meeting on ‘Alpha Emitting Radionuclides and Radiopharmaceuticals for Therapy’, from June 24 to 28, 2013, at IAEA Headquarters in Vienna with the purpose of gathering eminent Experts in the field and discuss with them the status and future perspectives of the field. Sixteen Experts and two External Observers from ten different countries, and four IAEA Technical Officers attended this meeting. Outstanding lectures have been presented covering all relevant aspects of α-therapy, which were followed by extensive discussions and analysis. Selected arguments encompassed production methods and availability of alpha-emitting radionuclides, labelling chemistry of alpha-emittting radioelements, design and development of target-specific radiopharmaceuticals, physical principles of alpha-particle dosimetry and advanced dosimetric models, biological effects of alpha radiation at the cellular level, on-going preclinical and clinical studies with new radiopharmaceuticals, results of clinical trials on the use of radium-223 chloride solutions for the treatment of metastatic bone cancer. The broad scientific background of invited components of the Experts’ panel conferred a strong interdisciplinary trait to the overall discussion and stimulated a critical analysis of this emerging unexplored field. Results of this comprehensive overview on alpha therapy, including recommendations to the Agency on suitable initiatives that may help to promote and spread the knowledge to Members States on this emerging therapeutic modality, are summarized in the present Report

  9. alpha-MSH activates immediate defense responses to UV-induced oxidative stress in human melanocytes.

    Science.gov (United States)

    Song, Xiuzu; Mosby, Nicole; Yang, Jennifer; Xu, Aie; Abdel-Malek, Zalfa; Kadekaro, Ana Luisa

    2009-12-01

    Exposure of cultured human melanocytes to ultraviolet radiation (UV) results in DNA damage. In melanoma, UV-signature mutations resulting from unrepaired photoproducts are rare, suggesting the possible involvement of oxidative DNA damage in melanocyte malignant transformation. Here we present data demonstrating immediate dose-dependent generation of hydrogen peroxide in UV-irradiated melanocytes, which correlated directly with a decrease in catalase activity. Pretreatment of melanocytes with alpha-melanocortin (alpha-MSH) reduced the UV-induced generation of 7,8-dihydro-8-oxyguanine (8-oxodG), a major form of oxidative DNA damage. Pretreatment with alpha-MSH also increased the protein levels of catalase and ferritin. The effect of alpha-MSH on 8-oxodG induction was mediated by activation of the melanocortin 1 receptor (MC1R), as it was absent in melanocytes expressing loss-of-function MC1R, and blocked by concomitant treatment with an analog of agouti signaling protein (ASIP), ASIP-YY. This study provides unequivocal evidence for induction of oxidative DNA damage by UV in human melanocytes and reduction of this damage by alpha-MSH. Our data unravel some mechanisms by which alpha-MSH protects melanocytes from oxidative DNA damage, which partially explain the strong association of loss-of-function MC1R with melanoma.

  10. Contribution to the calculation of the alpha value in the study of optimization on radiological protection

    International Nuclear Information System (INIS)

    Perez, Clarice de Freitas Acosta

    2007-01-01

    The Alpha value is an extremely important criterion because it determines the time that each country takes to reach its proposals to decrease the doses to workers involved with ionizing radiation sources. Presently, countries adopt a single value for alpha based in the annual gross national product, GNP, per capita. The aim of this paper is to show that it should be more efficient the selection of a curve for alpha in place of a single value. This curve, in its turn, should allow an alpha value that would be constraint to the greatest individual doses present in each optimization process, applied to design and operation. These maximum individual doses should represent the dose distribution between the workers team. To build the curve, alpha values suggested will not be based on the GNP per capita but on a distribution function of the maximum individual doses and on the time necessary to reach the goal of 1/10 of the annual dose limit, that is, to reach the region where the individual doses are considered acceptable. This new alpha value approach solves several problems risen by the present methodology, among which we emphasize: a) It can be accomplished only one optimization for each radiological protection option set; b) each country may have different constraints limits that can create serious problems in the international interchange; c) it avoids the possibility to calculate the probable death rate due to the collective dose. This type of calculation is undesirable to international organization. (author)

  11. Mechanisms of cell sensitization to alpha radioimmunotherapy by doxorubicin or paclitaxel in multiple myeloma cell lines.

    Science.gov (United States)

    Supiot, Stephane; Gouard, Sebastien; Charrier, Josiane; Apostolidis, Christos; Chatal, Jean-Francois; Barbet, Jacques; Davodeau, François; Cherel, Michel

    2005-10-01

    The purpose of this study was to analyze different mechanisms (cell cycle synchronization, DNA damage, and apoptosis) that might underlie potential synergy between chemotherapy (paclitaxel or doxorubicin) and radioimmunotherapy with alpha radionuclides. Three multiple myeloma cell lines (LP1, RMI 8226, and U266) were treated with 213Bi-radiolabeled B-B4, a monoclonal antibody that recognizes syndecan-1 (CD138) 24 hours after paclitaxel (1 nmol/L) or doxorubicin (10 nmol/L) treatment. Cell survival was assessed using a clonogenic survival assay. Cell cycle modifications were assessed by propidium iodide staining and DNA strand breaks by the comet assay. Level of apoptosis was determined by Apo 2.7 staining. Radiation enhancement ratio showed that paclitaxel and doxorubicin were synergistic with alpha radioimmunotherapy. After a 24-hour incubation, paclitaxel and doxorubicin arrested all cell lines in the G2-M phase of the cell cycle. Doxorubicin combined with alpha radioimmunotherapy increased tail DNA in the RPMI 8226 cell line but not the LP1 or U266 cell lines compared with doxorubicin alone or alpha radioimmunotherapy alone. Neither doxorubicin nor paclitaxel combined with alpha radioimmunotherapy increased the level of apoptosis induced by either drug alone or alpha radioimmunotherapy alone. Both cell cycle arrest in the G2-M phase and an increase in DNA double-strand breaks could lead to radiosensitization of cells by doxorubicin or paclitaxel, but apoptosis would not be involved in radiosensitization mechanisms.

  12. Radiation-induced cardiovascular effects

    Science.gov (United States)

    Tapio, Soile

    Recent epidemiological studies indicate that exposure to ionising radiation enhances the risk of cardiovascular mortality and morbidity in a moderate but significant manner. Our goal is to identify molecular mechanisms involved in the pathogenesis of radiation-induced cardiovascular disease using cellular and mouse models. Two radiation targets are studied in detail: the vascular endothelium that plays a pivotal role in the regulation of cardiac function, and the myocardium, in particular damage to the cardiac mitochondria. Ionising radiation causes immediate and persistent alterations in several biological pathways in the endothelium in a dose- and dose-rate dependent manner. High acute and cumulative doses result in rapid, non-transient remodelling of the endothelial cytoskeleton, as well as increased lipid peroxidation and protein oxidation of the heart tissue, independent of whether exposure is local or total body. Proteomic and functional changes are observed in lipid metabolism, glycolysis, mitochondrial function (respiration, ROS production etc.), oxidative stress, cellular adhesion, and cellular structure. The transcriptional regulators Akt and PPAR alpha seem to play a central role in the radiation-response of the endothelium and myocardium, respectively. We have recently started co-operation with GSI in Darmstadt to study the effect of heavy ions on the endothelium. Our research will facilitate the identification of biomarkers associated with adverse cardiac effects of ionising radiation and may lead to the development of countermeasures against radiation-induced cardiac damage.

  13. Environmental radiation monitoring around the nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Woo; Choi, Geun Sik and others

    2001-02-01

    Environmental Radiation Monitoring was carried out with measurement of environment. Radiation and environmental radioactivity analysis around KAERI nuclear facilities and Seoul Research Reactor. The results of environmental radiation monitoring around KAERI nuclear facilities and Seoul Research Reactor are the follows : The average level of environmental radiation dose measured by NaI scintillation counter and accumulated radiation dose by TLD was almost same level compared with the past years. Gross {alpha}, {beta} radioactivity in environmental samples showed a environmental level. {gamma}-radionuclides in water samples were not detected. But only radionuclide K-40, which is natural radionuclide, was detected in the all samples and Cs-137 was detected in the surface soil and discharge sediment. The average level of environmental radiation dose around Seoul Research Reactor was almost same level compared with the past years, and Be-7 and Cs-137 were detected in some surface soil and discharge sediment by {gamma}-spectrometry.

  14. Radiation synthesis of materials and compounds

    CERN Document Server

    Kharisov, Boris Ildusovich; Ortiz Méndez, Ubaldo

    2013-01-01

    Researchers and engineers working in nuclear laboratories, nuclear electric plants, and elsewhere in the radiochemical industries need a comprehensive handbook describing all possible radiation-chemistry interactions between irradiation and materials, the preparation of materials under distinct radiation types, the possibility of damage of materials under irradiation, and more. Radiation nanotechnology is still practically an undeveloped field, except for some achievements in the fabrication of metallic nanoparticles under ionizing flows. Radiation Synthesis of Materials and Compounds presents the state of the art of the synthesis of materials, composites, and chemical compounds, and describes methods based on the use of ionizing radiation. It is devoted to the preparation of various types of materials (including nanomaterials) and chemical compounds using ionizing radiation (alpha particles, beta particles, gamma rays, x-rays, and neutron, proton, and ion beams). The book presents contributions from leaders ...

  15. Environmental radiation monitoring around the nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Geun Sik; Lee, Chang Woo; Joo, Young Hyun [and others

    2005-04-01

    Environmental Radiation Monitoring was carried out with measurement of environment. radiation and environmental radioactivity analysis around KAERI nuclear facilities and Seoul Research Reactor. The results of environmental radiation monitoring around KAERI nuclear facilities and Seoul Research Reactor are the follows : The average level of environmental radiation dose measured by NaI scintillation counter and accumulated radiation dose by TLD was almost same level compared with the past years. Gross {alpha} ,{beta} radioactivity in environmental samples showed a environmental level. {gamma}-radionuclides in water samples were not detected. But only radionuclide K-40, which is natural radionuclide, was detected in the all samples and Cs-137 was detected in the surface soil and discharge sediment. The average level of environmental radiation dose around Seoul Research Reactor was almost same level compared with the past years, and Be-7 and Cs-137 were detected in some surface soil and discharge sediment by {gamma}-spectrometry.

  16. Determination by transfer reaction of alpha widths in fluorine for astrophysical interest; Determination par reaction de transfert de largeurs alpha dans le fluor 19. Applications a l'astrophysique

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Santos, F. de

    1995-04-15

    The nucleosynthesis of fluorine is not known. Several astrophysical models predict the alpha radiative capture onto N{sup 15} as the main fluorine production reaction. In the expression of the reaction rate, one parameter is missing: the alpha width of the resonance on the E = 4.377 MeV level in fluorine. A direct measurement is excluded due to the very low cross-section expected. We have determined this alpha width using a transfer reaction followed by analyses with FR-DWBA (Finite Range Distorted Wave Born Approximation) in a simple cluster alpha model. This experiment was carried out with a Li{sup 7} beam with E = 28 MeV onto a N{sup 15} gas target. The 16 first levels were studied. Spectroscopic factors were extracted for most of them. Alpha widths for unbound levels were determined. Many alpha width were compared with known values from direct reaction and the differences lie within the uncertainty range (factor 2). The alpha width for the E = 4.377 MeV level was determined ({gamma}{sub {alpha}} = 1.5*10{sup -15} MeV), its value is about 60 times weaker than the used value. The influence of our new rate was studied in AGB (Asymptotic Giant Branch) stars during thermal pulses. In this model the alteration is sensitive. (author)

  17. Hypothalamic PGC-1 alpha Protects Against High-Fat Diet Exposure by Regulating ER alpha

    NARCIS (Netherlands)

    Morselli, Eugenia; Fuente-Martin, Esther; Finan, Brian; Kim, Min; Frank, Aaron; Garcia-Caceres, Cristina; Navas, Carlos Rodriguez; Gordillo, Ruth; Neinast, Michael; Kalainayakan, Sarada P.; Li, Dan L.; Gao, Yuanqing; Yi, Chun-Xia; Hahner, Lisa; Palmer, Biff F.; Tschöp, Matthias H.; Clegg, Deborah J.

    2014-01-01

    High-fat diets (HFDs) lead to obesity and inflammation in the central nervous system (CNS). Estrogens and estrogen receptor alpha (ER alpha) protect premenopausal females from the metabolic complications of inflammation and obesity-related disease. Here, we demonstrate that hypothalamic PGC-1 alpha

  18. Tumor necrosis factor alpha (TNF alpha) in human skin : A comparison of different antibodies for immunohistochemistry

    NARCIS (Netherlands)

    van der Laan, N; de Leij, LFMH; Buurman, W; Timens, W; ten Duis, HJ

    Conflicting results have been reported regarding the localization and presence of TNF alpha in normal human skin, To study TNF alpha expression, we tested a panel of antibodies directed against human TNF alpha, First, antibodies were tested for immunoreactivity on cytospots of isolated

  19. Study of the pygmy dipole resonance in Mo-94 using the (alpha, alpha ' gamma) coincidence technique

    NARCIS (Netherlands)

    Derya, V.; Endres, J.; Elvers, M.; Harakeh, M. N.; Pietralla, N.; Romig, C.; Savran, D.; Scheck, M.; Siebenhuehner, F.; Stoica, V. I.; Wortche, H. J.; Zilges, A.

    2013-01-01

    The (alpha, alpha' gamma) reaction at E-alpha = 136 MeV was used to study the electric dipole response in the open-shell vibrational nucleus Mo-94 below the neutron-separation threshold. The coincidence experiment has been performed at the Kernfysisch Versneller Instituut in Groningen, The

  20. Radiation effects in silicate glasses

    International Nuclear Information System (INIS)

    Bibler, N.E.; Howitt, D.G.

    1988-01-01

    The study of radiation effects in complex silicate glasses has received renewed attention because of their use in special applications such as high level nuclear waste immobilization and fiber optics. Radiation changes the properties of these glasses by altering their electronic and atomic configurations. These alterations or defects may cause dilatations or microscopic phase changes along with absorption centers that limit the optical application of the glasses. Atomic displacements induced in the already disordered structure of the glasses may affect their use where heavy irradiating particles such as alpha particles, alpha recoils, fission fragments, or accelerated ions are present. Large changes (up to 1%) in density may result. In some cases the radiation damage may be severe enough to affect the durability of the glass in aqueous solutions. In the paper, the authors review the literature concerning radiation effects on density, durability, stored energy, microstructure and optical properties of silicate glasses. Both simple glasses and complex glasses used for immobilization of nuclear waste are considered

  1. Radiation related basic cancer research

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Hoon; Yoo, Young Do; Hong, Seok Il [and others

    2000-04-01

    We studied the mechanism of radiation-induced apoptosis, the factors involved signaling, and the establishment of radiation-resistant cell lines in this study. During the TGF beta-stimulated epithelial mesenchymal transition(EMT), actin rearrangement occurred first and fibronectin matrix assembly followed. These two events were considered independent since cytochalasin-D did not inhibit TGF stimulated matrix assembly and fibronectin supplementation did not induce EMT. During EMT, alpha 5 beta 1 integrin and alpha v integrin have increased but MMP activation was not accompanied, which suggest that induction of extracellular matrix and activation of integrins may be main contributor for the EMT. Serum depriving induced apoptosis of HUVECs was prevented by vascular endothelial growth factor(VEGF) and PMA. The apoptosis prevention by VEGF and PMA were conformed by DNA fragmentation assay. The p53 expression level was down regulated by VEGF and PMA compared with serum deprived HUVECs. However, VEGF and PMA induces c-Myc expression level on these cells. We made the 5 radiation-resistant clones from breast, lung and cervical cancer cells. More than 70%, 100% and 50% increased resistance was detected in breast cancer cells, lung cancer cells, and cervical cells, respectively. We carried out differential display-PCR to clone the radiation-resistant genes. 9 out of 10 genes were analyzed their sequence.

  2. Radiation related basic cancer research

    International Nuclear Information System (INIS)

    Lee, Seung Hoon; Yoo, Young Do; Hong, Seok Il

    2000-04-01

    We studied the mechanism of radiation-induced apoptosis, the factors involved signaling, and the establishment of radiation-resistant cell lines in this study. During the TGF beta-stimulated epithelial mesenchymal transition(EMT), actin rearrangement occurred first and fibronectin matrix assembly followed. These two events were considered independent since cytochalasin-D did not inhibit TGF stimulated matrix assembly and fibronectin supplementation did not induce EMT. During EMT, alpha 5 beta 1 integrin and alpha v integrin have increased but MMP activation was not accompanied, which suggest that induction of extracellular matrix and activation of integrins may be main contributor for the EMT. Serum depriving induced apoptosis of HUVECs was prevented by vascular endothelial growth factor(VEGF) and PMA. The apoptosis prevention by VEGF and PMA were conformed by DNA fragmentation assay. The p53 expression level was down regulated by VEGF and PMA compared with serum deprived HUVECs. However, VEGF and PMA induces c-Myc expression level on these cells. We made the 5 radiation-resistant clones from breast, lung and cervical cancer cells. More than 70%, 100% and 50% increased resistance was detected in breast cancer cells, lung cancer cells, and cervical cells, respectively. We carried out differential display-PCR to clone the radiation-resistant genes. 9 out of 10 genes were analyzed their sequence

  3. EUV sources for the alpha-tools

    Science.gov (United States)

    Pankert, Joseph; Apetz, Rolf; Bergmann, Klaus; Damen, Marcel; Derra, Günther; Franken, Oliver; Janssen, Maurice; Jonkers, Jeroen; Klein, Jürgen; Kraus, Helmar; Krücken, Thomas; List, Andreas; Loeken, Micheal; Mader, Arnaud; Metzmacher, Christof; Neff, Willi; Probst, Sven; Prümmer, Ralph; Rosier, Oliver; Schwabe, Stefan; Seiwert, Stefan; Siemons, Guido; Vaudrevange, Dominik; Wagemann, Dirk; Weber, Achim; Zink, Peter; Zitzen, Oliver

    2006-03-01

    In this paper, we report on the recent progress of the Philips Extreme UV source. The Philips source concept is based on a discharge plasma ignited in a Sn vapor plume that is ablated by a laser pulse. Using rotating electrodes covered with a regenerating tin surface, the problems of electrode erosion and power scaling are fundamentally solved. Most of the work of the past year has been dedicated to develop a lamp system which is operating very reliably and stable under full scanner remote control. Topics addressed were the development of the scanner interface, a dose control system, thermo-mechanical design, positional stability of the source, tin handling, and many more. The resulting EUV source-the Philips NovaTin(R) source-can operate at more than 10kW electrical input power and delivers 200W in-band EUV into 2π continuously. The source is very small, so nearly 100% of the EUV radiation can be collected within etendue limits. The lamp system is fully automated and can operate unattended under full scanner remote control. 500 Million shots of continuous operation without interruption have been realized, electrode lifetime is at least 2 Billion shots. Three sources are currently being prepared, two of them will be integrated into the first EUV Alpha Demonstration tools of ASML. The debris problem was reduced to a level which is well acceptable for scanner operation. First, a considerable reduction of the Sn emission of the source has been realized. The debris mitigation system is based on a two-step concept using a foil trap based stage and a chemical cleaning stage. Both steps were improved considerably. A collector lifetime of 1 Billion shots is achieved, after this operating time a cleaning would be applied. The cleaning step has been verified to work with tolerable Sn residues. From the experimental results, a total collector lifetime of more than 10 Billion shots can be expected.

  4. Alpha Radiolysis of Nuclear Solvent Extraction Ligands Used for An(III) and Ln(III) Separations

    Energy Technology Data Exchange (ETDEWEB)

    Mezyk, Stephen P. [California State Univ. (CalState), Long Beach, CA (United States); Mincher, Bruce J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Nilsson, Mikael [Univ. of California, Irvine, CA (United States)

    2016-08-01

    This document is the final report for the Nuclear Energy Universities Program (NEUP) grant 10-910 (DE-AC07-05ID14517) “Alpha Radiolysis of Nuclear Solvent Extraction Ligands used for An(III) and Ln(III) Separations”. The goal of this work was to obtain a quantitative understanding of the impacts of both low Linear Energy Transfer (LET, gamma-rays) and high LET (alpha particles) radiation chemistry occurring in future large-scale separations processes. This quantitative understanding of the major radiation effects on diluents and ligands is essential for optimal process implementation, and could result in significant cost savings in the future.

  5. Nuclear radiation-warning detector that measures impedance

    Science.gov (United States)

    Savignac, Noel Felix; Gomez, Leo S; Yelton, William Graham; Robinson, Alex; Limmer, Steven

    2013-06-04

    This invention is a nuclear radiation-warning detector that measures impedance of silver-silver halide on an interdigitated electrode to detect light or radiation comprised of alpha particles, beta particles, gamma rays, X rays, and/or neutrons. The detector is comprised of an interdigitated electrode covered by a layer of silver halide. After exposure to alpha particles, beta particles, X rays, gamma rays, neutron radiation, or light, the silver halide is reduced to silver in the presence of a reducing solution. The change from the high electrical resistance (impedance) of silver halide to the low resistance of silver provides the radiation warning that detected radiation levels exceed a predetermined radiation dose threshold.

  6. Medical radiation

    Energy Technology Data Exchange (ETDEWEB)

    1992-06-01

    This leaflet in the At-a-Glance Series describes the medical use of X-rays, how X-rays help in diagnosis, radiation protection of the patient, staff protection, how radioactive materials in nuclear medicine examinations help in diagnosis and the use of radiation in radiotherapy. Magnetic resonance imaging, a diagnostic technique involving no ionizing radiation, is also briefly examined. The role of the NRPB in the medical use of radiation is outlined. (UK).

  7. Radiation watchdog

    International Nuclear Information System (INIS)

    Manning, R.

    1984-01-01

    Designated by WHO as a Collaborating Centre, the Radiation Emergency Assistance Center/Training Site (REAC/TS) in Oak Ridge, Tennessee provides assistance to all countries of the Americas in radiation accidents including human contamination or overexposure. It also conducts courses in radiation emergency response for health professionals from throughout the world

  8. Radiation Exposure

    Science.gov (United States)

    Radiation is energy that travels in the form of waves or high-speed particles. It occurs naturally in sunlight. Man-made radiation is used in X-rays, nuclear weapons, nuclear power plants and cancer treatment. If you are exposed to small amounts of radiation over a long ...

  9. Radiation damage measurements in room-temperature semiconductor radiation detectors

    CERN Document Server

    Franks, L A; Olsen, R W; Walsh, D S; Vizkelethy, G; Trombka, J I; Doyle, B L; James, R B

    1999-01-01

    The literature of radiation damage measurements on cadmium zinc telluride (CZT), cadmium telluride (CT), and mercuric iodide (HgI sub 2) is reviewed and in the case of CZT supplemented by new alpha particle data. CZT strip detectors exposed to intermediate energy (1.3 MeV) proton fluences exhibit increased interstrip leakage after 10 sup 1 sup 0 p/cm sup 2 and significant bulk leakage after 10 sup 1 sup 2 p/cm sup 2. CZT exposed to 200 MeV protons shows a two-fold loss in energy resolution after a fluence of 5x10 sup 9 p/cm sup 2 in thick (3 mm) planar devices but little effect in 2 mm devices. No energy resolution effects were noted from a moderated fission spectrum of neutrons after fluences up to 10 sup 1 sup 0 n/cm sup 2 , although activation was evident. Exposures of CZT to 5 MeV alpha particles at fluences up to 1.5x10 sup 1 sup 0 alpha/cm sup 2 produced a near linear decrease in peak position with fluence and increases in FWHM beginning at about 7.5x10 sup 9 alpha/cm sup 2. CT detectors show resolution...

  10. Anomalous Temporal Behaviour of Broadband Ly Alpha Observations During Solar Flares from SDO/EVE

    Science.gov (United States)

    Milligan, Ryan O.; Chamberlin, Phillip C.

    2016-01-01

    Although it is the most prominent emission line in the solar spectrum, there has been a notable lack of studies devoted to variations in Lyman-alpha (Ly-alpha) emission during solar flares in recent years. However, the few examples that do exist have shown Ly-alpha emission to be a substantial radiator of the total energy budget of solar flares (of the order of 10 percent). It is also a known driver of fluctuations in the Earth's ionosphere. The EUV (Extreme Ultra-Violet) Variability Experiment (EVE) on board the Solar Dynamics Observatory (SDO) now provides broadband, photometric Ly-alpha data at 10-second cadence with its Multiple EUV Grating Spectrograph-Photometer (MEGS-P) component, and has observed scores of solar flares in the 5 years since it was launched. However, the MEGS-P time profiles appear to display a rise time of tens of minutes around the time of the flare onset. This is in stark contrast to the rapid, impulsive increase observed in other intrinsically chromospheric features (H-alpha, Ly-beta, LyC, C III, etc.). Furthermore, the emission detected by MEGS-P peaks around the time of the peak of thermal soft X-ray emission and not during the impulsive phase when energy deposition in the chromosphere (often assumed to be in the form of non-thermal electrons) is greatest. The time derivative of Ly-alpha lightcurves also appears to resemble that of the time derivative of soft X-rays, reminiscent of the Neupert effect. Given that spectrally-resolved Ly-alpha observations during flares from SORCE / SOLSTICE (Solar Radiation and Climate Experiment / Solar Stellar Irradiance Comparison Experiment) peak during the impulsive phase as expected, this suggests that the atypical behaviour of MEGS-P data is a manifestation of the broadband nature of the observations. This could imply that other lines andor continuum emission that becomes enhanced during flares could be contributing to the passband. Users are hereby urged to exercise caution when interpreting

  11. Psychiatric Symptoms in Alpha-Mannosidosis

    Science.gov (United States)

    Malm, D.; Pantel, J.; Linaker, O. M.

    2005-01-01

    Alpha-mannosidosis is characterized by mild to moderate intellectual disability (ID), moderate to severe neurosensory hearing loss, frequent infections, psychomotor disturbances and skeletal dysmorphism. For the first time, a panel of nine alpha-mannosidosis patients with psychiatric symptoms is presented. The clinical picture has several…

  12. Coefficient Alpha Bootstrap Confidence Interval under Nonnormality

    Science.gov (United States)

    Padilla, Miguel A.; Divers, Jasmin; Newton, Matthew

    2012-01-01

    Three different bootstrap methods for estimating confidence intervals (CIs) for coefficient alpha were investigated. In addition, the bootstrap methods were compared with the most promising coefficient alpha CI estimation methods reported in the literature. The CI methods were assessed through a Monte Carlo simulation utilizing conditions…

  13. Alpha Shape Topology of the Cosmic Web

    NARCIS (Netherlands)

    Weygaert, Rien van de; Platen, Erwin; Vegter, Gert; Eldering, Bob; Kruithof, Nico

    2010-01-01

    We study the topology of the Megaparsec Cosmic Web on the basis of the Alpha Shapes of the galaxy distribution. The simplicial complexes of the alpha shapes are used to determine the set of Betti numbers (βk, k = 1, . . . , D), which represent a complete characterization of the topology of a

  14. Central and peripheral alpha-adrenoceptors

    NARCIS (Netherlands)

    van Zwieten, P A; van Meel, J. C. A.; de Jonge, A; Wilffert, B; Timmermans, P B

    1982-01-01

    The recent interest in the characterization and functional, role of alpha-adrenoceptors has prompted us to study the following different, although interdigitated, lines of research: (a) The functional role of calcium ions in the process of vasoconstriction, induced by alpha 2-adrenoceptor

  15. Producing alpha-olefins using polyketide synthases

    Energy Technology Data Exchange (ETDEWEB)

    Fortman, Jeffrey L.; Katz, Leonard; Steen, Eric J.; Keasling, Jay D.

    2018-01-02

    The present invention provides for a polyketide synthase (PKS) capable of synthesizing an .alpha.-olefin, such as 1-hexene or butadiene. The present invention also provides for a host cell comprising the PKS and when cultured produces the .alpha.-olefin.

  16. Bayesian Meta-Analysis of Coefficient Alpha

    Science.gov (United States)

    Brannick, Michael T.; Zhang, Nanhua

    2013-01-01

    The current paper describes and illustrates a Bayesian approach to the meta-analysis of coefficient alpha. Alpha is the most commonly used estimate of the reliability or consistency (freedom from measurement error) for educational and psychological measures. The conventional approach to meta-analysis uses inverse variance weights to combine…

  17. ALPHA experiment facility and Prof. Jeffrey Hangst.

    CERN Multimedia

    Maximilien Brice

    2010-01-01

    Picture 01-07: General views of the ALPHA experiment Picture 5: Andrea Gutierrez, a PhD student from UBC, transfers liquid helium from a storage dewar into the cryostat containing the superconducting magnetic trap used by the ALPHA experiment.Picture 08-11: Jeffery Hangst, spokesperson for ALPHA Picture 12: The ALPHA silicon detector, which surrounds the trapping resion and is used for imaging antiproton annihilations (Credit University of Liverpool) Picture 13: Untrapped antihydrogen atoms annihilating on the inner surface of the ALPHA trap. These are measured by the ALPHA annihilation detector. The events are concentrated at the electrode radius of about 22.3 mm. The coordinates are defined in the Nature article, Figure 1b. Picture 14: The electrodes (gold) for the ALPHA Penning trap being inserted into the vacuum chamber and cryostat assembly. This is the trap used to combine or "mix" positrons and antiprotons to make antihydrogen. (Credit: Niels Madsen ALPHA/Swansea.) Picture 15: Top, a diagram of the...

  18. Alpha-1 Antitrypsin Deficiency (Inherited Emphysema)

    Science.gov (United States)

    ... antitrypsin inactivates elastase once it has finished its job. Without alpha 1 antitrypsin, elastase can destroy the air sacs of the lung. How is the diagnosis made? Because Alpha-1 related disease is COPD, the diagnosis is made by the same methods. Your doctor may have you do a number ...

  19. A stable lipid-induced aggregate of alpha-synuclein

    NARCIS (Netherlands)

    Drescher, Malte; van Rooijen, Bart D; Veldhuis, Gertjan; Subramaniam, Vinod; Huber, Martina

    2010-01-01

    The Parkinson's disease-related protein alpha-Synuclein (alphaS) is a 140 residue intrinsically disordered protein. Its membrane-binding properties are thought to be relevant for its physiological or pathologic activity. Here, the interaction of alphaS with POPG

  20. INFLUENCIA DE LA PRESIÓN ATMOSFÉRICA EN LAS TRANSMISIONES A FRECUENCIA 2.4 GHz

    OpenAIRE

    González Romero, Pedro Vicente; Espina Ávila, Luis Gerardo

    2012-01-01

    La presente investigación se planteó como propósito fundamental determinar la influencia de la presión atmosférica sobre una señal transmitida en una frecuencia de 2.4 GHz. La investigación es de tipo explicativa, con diseño metodológico experimental. Mediante ella se obtiene la atenuación de una señal de 2.4GHz a diferentes presiones atmosféricas y se determinan las gráficas que muestran el comportamiento observado. Como resultado de esta investigación se observó que sí existe una influencia...

  1. Influencia de la autoestima y del apoyo social percibido sobre el bienestar psicológico de estudiantes universitarios chilenos

    Directory of Open Access Journals (Sweden)

    Enrique Barra Almagia

    2012-01-01

    Full Text Available El presente estudio, de tipo correlacional transeccional, examinó la influencia de la autoestima y del apoyo social percibido sobre el bienestar psicológico, en una muestra de 450 estudiantes de ambos sexos de la Universidad de Concepción, Chile, quienes respondieron las Escalas de Autoestima de Rosenberg, de Bienestar Psicológico de Ryff y el Cuestionario de Apoyo Social Percibido. Se encontró que la autoestima tenía una influencia mayor sobre el bienestar psicológico que el apoyo social percibido. Aunque no hubo diferencias de sexo en el bienestar psicológico global, se observaron diferencias a favor de los hombres en las dimensiones de autoaceptación y autonomía, y a favor de las mujeres, en crecimiento personal, así como diferencias a favor de los hombres en autoestima y a favor de las mujeres en apoyo socialpercibido.

  2. ROL DE LOS RIOS TRIBUTARIOS EN LOS SISTEMAS LACUSTRE Y MARINO COSTERO NOR-PATAGONICOS BAJO INFLUENCIA ANTROPICA

    OpenAIRE

    LEON MUÑOZ, JORGE EDUARDO

    2011-01-01

    Primer Capítulo se abordó la hipótesis específica Hl, analizándose la variabilidad interanual (años 1944- 2007) del régimen hidrológico del río Puelo (41.5°S, Q = 650 m3/seg) y su influencia en la capa superficial del fiordo Reloncaví, uno de los sistemas costeros más importantes para la salmonicultura nacional. La importancia del estudio radicó en analizar la relación río/fiordo en escenarios contrastantes de caudal, ésto permitió registrar cómo la influencia del río Puelo es altamente...

  3. INFLUENCIA DE LOS INVERSIONISTAS INSTITUCIONALES EN LAS DECISIONES DE ESTRUCTURA DE CAPITAL DE LA EMPRESA. Evidencia para un mercado emergente

    Directory of Open Access Journals (Sweden)

    Felipe Araya Sepúlveda

    2015-01-01

    Full Text Available Este artículo analiza empíricamente la influencia de las Administradoras de Fondos de Pensión (AFP como principales accionistas institucionales, sobre las decisiones de estructura de capital de la empresa chilena. Estos inversionistas pueden influir en la estructura de capital mediante distintos papeles como los de monitoreo a la gestión y de recopilación y transferencia de información al mercado. El análisis es desarrollado durante el periodo 2009-2011 para una muestra de 109 empresas chilenas que cotizan en la bolsa. Las AFP no sólo participan en el mercado accionario sino que también compiten por la deuda pública, por lo que nuestros resultados son relevantes al indicar la positiva influencia de este tipo de inversionistas en la contratación y emisión de deuda, particularmente la pública.

  4. C595 antibody: A potential vector for targeted alpha therapy

    International Nuclear Information System (INIS)

    Perkins, A.C.; Allen, B.J.

    2005-01-01

    Full text: Mucins are high molecular-weight heavily glycosylated glycoproteins with many oligosaccharide side-chains, linked to a protein backbone called apomucin. A total of 19 different mucin genes (MUC1-MUC4, MUC5B, MUC5AC, MUC6-MUC18) have been identified to date. Mucins are present on the surface of most epithelial cells and play a role in their protection and lubrication. In cancer cells the mucin molecule becomes altered, thus representing an important target for diagnosis and therapy. Urinary epithelial mucin1 (MUC1) is found to be frequently up-regulated and abnormally glycosylated in a number of common malignancies, including breast, bladder, colon, ovarian and gastric cancer. The monoclonal antibody C595 is an IgG3 murine MAb raised against the protein core of human MUC1. Epitope mapping has shown that C595 recognizes a tetrapeptide motif (RPAP) within the protein core of MUC1 mucin that contains a large domain of multiples of a highly conserved 20-amino-acid-repeat sequence (PDTRPAPGSTAPPAHGVTSA). This antibody has previously been radiolabelled with 99m Tc and 111 In and used for imaging a range of tumour types including ovary, breast and bladder. The antibody has also been radiolabelled with 67 Cu and 188 Re for the therapy of superficial bladder cancer. More recently we have investigated the pre-clinical use of the C595 antibody for targeted alpha therapy using 213 Bi which emits alpha particles with high linear energy transfer (LET), short range (80 m) radiation and has a short physical half-life of 45.6 minutes. Alpha particles are some 7300 times heavier than beta particles and in theory, following binding of an alpha immunocongugates to the target, a large fraction of the alpha particle energy is delivered to cancer cells, with minimal concomitant radiation of normal tissues. 213 Bi was produced from the 225 Ac/ 213 Bi generator. For antibody conjugation the chelator, cyclic diethylenetriaminepentacetic acid anhydride (DTPA) was used. Initial

  5. Use of studies with laboratory animals to assess the potential early health effects of combined internal alpha and beta irradiation

    International Nuclear Information System (INIS)

    Scott, B.R.; Hahn, F.F.; Guilmette, R.A.; Muggenburg, B.A.; Snipes, M.B.; Boecker, B.B.; McClellan, R.O.

    1986-01-01

    The potential health impacts of radionuclides released in nuclear accidents are of major concern to the public and to regulatory and other governmental agencies. One mode of potential exposure is by inhalation of airborne radionuclides, which could lead to combined internal irradiation by high (alpha) and low (beta) linear energy transfer (LET) radiations. Epidemiological data for health effects of human inhalation exposure are too limited to derive reliable estimates of risks of potential health effects. However, results of studies in which beagle dogs were exposed by inhalation to insoluble radioactive aerosols can be used to estimate expected effects in humans. Data for mortality from radiation pneumonitis and pulmonary fibrosis caused by internal irradiation of dog lungs by alpha or beta radiations are used to derive the relative biological effectiveness (RBE) of alpha irradiation compared to beta irradiation; predict the expected combined effects of alpha and beta irradiation of dog lungs; and extrapolate the results to humans. The extrapolation to humans assumed that, for similar ages at exposure, dog and human lungs have similar sensitivities to lung irradiation. Results of theoretical calculations related to mortality from early effects indicated that the synergistic effects of high- and low-LET radiations should depend on the percentages of the total dose contributed by high- and low-LET radiations, and for very low or very high doses, synergistic effects should be negligible. 23 refs., 8 figs

  6. Characterization of saturation of CR-39 detector at high alpha-particle fluence

    Directory of Open Access Journals (Sweden)

    M. El Ghazaly

    2018-04-01

    Full Text Available The occurrence of saturation in the CR-39 detector reduces and limits its detection dynamic range; nevertheless, this range could be extended using spectroscopic techniques and by measuring the net bulk rate of the saturated CR-39 detector surface. CR-39 detectors were irradiated by 1.5 MeV high alpha-particle fluence varying from 0.06 × 108 to 7.36 × 108 alphas/cm2 from Am-241 source; thereafter, they were etched in a 6.25N NaOH solution at a temperature of 70°C for different durations. Net bulk etch rate measurement of the 1.5 MeV alpha-irradiated CR-39 detector surface revealed that rate increases with increasing etching time and reaches its maximum value at the end of the alpha-particle range. It is also correlated with the alpha-particle fluence. The measurements of UV–Visible (UV–Vis absorbance at 500 and 600 nm reveal that the absorbance is linearly correlated with the fluence of alpha particles at the etching times of 2 and 4 hour. For extended etching times of 6, 10, and 14.5 hour, the absorbance is saturated for fluence values of 4.05 × 108, 5.30 × 108, and 7.36 × 108 alphas/cm2. These new methods pave the way to extend the dynamic range of polymer-based solid state nuclear track detectors (SSNTDs in measurement of high fluence of heavy ions as well as in radiation dosimetry. Keywords: Alpha Particle, Bulk Etch Rate, CR-39 Detector, Saturated Regime, UV–Vis Spectroscopy

  7. Improved peak shape fitting in alpha spectra.

    Science.gov (United States)

    Pommé, S; Caro Marroyo, B

    2015-02-01

    Peak overlap is a recurrent issue in alpha-particle spectrometry, not only in routine analyses but also in the high-resolution spectra from which reference values for alpha emission probabilities are derived. In this work, improved peak shape formulae are presented for the deconvolution of alpha-particle spectra. They have been implemented as fit functions in a spreadsheet application and optimum fit parameters were searched with built-in optimisation routines. Deconvolution results are shown for a few challenging spectra with high statistical precision. The algorithm outperforms the best available routines for high-resolution spectrometry, which may facilitate a more reliable determination of alpha emission probabilities in the future. It is also applicable to alpha spectra with inferior energy resolution. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Radiation imaging

    Energy Technology Data Exchange (ETDEWEB)

    Redmayne, I.

    1986-05-21

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed.

  9. Radiation imaging

    International Nuclear Information System (INIS)

    Redmayne, Ian.

    1986-01-01

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed. (author)

  10. Technical Basis for the Use of Alpha Absorption Corrections on RCF Gross Alpha Data

    International Nuclear Information System (INIS)

    Ceffalo, G.M.

    1999-01-01

    This document provides the supporting data and rationale for making absorption corrections to gross alpha data to correct alpha data for loss due to absorption in the sample matrix. For some time there has been concern that the gross alpha data produced by the Environmental Restoration Contractor Radiological Counting Facility, particularly gross alpha analysis on soils, has been biased toward low results, as no correction for self-absorption was applied to the counting data. The process was investigated, and a new methodology for alpha self-absorption has been developed

  11. Elimination of alpha-gal xenoreactive epitope: alpha-galactosidase treatment of porcine heart valves.

    Science.gov (United States)

    Choi, Sun-Young; Jeong, Hee-Jin; Lim, Hong-Gook; Park, Seong-Sik; Kim, Soo-Hwan; Kim, Yong Jin

    2012-05-01

    Porcine heart valves are among the most widely used tissue valves in clinical heart valve implantation. However, immunologic responses have been implicated as potential causes of the limited durability of xenograft heart valves. The study aim was to determine the effectiveness of alpha-galactosidase treatment used to degrade the major xenoreactive antigens found in xenograft heart valves. Fresh porcine heart valves and pericardium treated with alpha-galactosidase were studied to evaluate the xenoreactive galactose (alpha1,3) galactose (alpha-gal) antigen. Removal of the alpha-gal epitope from the porcine heart valve was monitored via 3,3'-diaminobenzidine staining intensity, while the removal of alpha-gal from N-glycans on porcine heart valves treated with recombinant alpha-galactosidase was determined either qualitatively or quantitatively by mass fingerprinting using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The porcine pericardium was used for monitoring the change in mechanical properties after alpha-galactosidase treatment. In addition, the biomechanical modification property of collagen fiber rearrangement on tissue was assessed using transmission electron microscopy (TEM). Following a 24-h incubation at pH 7.2, 4 degrees C, employing 0.1 U/ml of Bacteroides thetaiotaomicron-derived recombinant alpha-galactosidase, the enzyme effectively removed the alpha-gal epitopes expressed on porcine heart valves. The identification type of alpha-gal N-glycan on fresh aortic valve, aortic wall, pulmonary valve, and pulmonary wall was 7.1%, 10.3%, 6% and 8%, respectively. In the presence of alpha-galactosidase treatment, alpha-gal-containing N-glycans were converted into alpha-gal-negative N-glycans. Likewise, alpha-gal-containing N-glycans were not detected when MALDI-TOF MS quantitative analysis was used. Furthermore, no significant difference was observed in the mechanical properties and findings from TEM in alpha

  12. Moessbauer spectroscopy with synchrotron radiation

    International Nuclear Information System (INIS)

    Bergmann, U.

    1994-01-01

    The short pulse nature of synchrotron radiation makes it possible to perform Moessbauer spectroscopy in the time domain, i.e. instead of measuring the transmitted intensity time integrated as a function of source/absorber velocity, the intensity of the scattered radiation is measured time differential. The resulting time spectrum is essentially source independent and complications in the data analysis which are related to the radioactive source are completely removed. Furthermore, the large brightness and well defined polarization of the synchrotron radiation can, e.g., speed up the data collection and facilitate studies of polarization phenomena. To illustrate these new spectroscopic possibilities, measurements of the temperature dependence and polarization dependence of forward scattering from alpha - sup 5 sup 7 Fe nuclei are presented and discussed 26 refs., 5 figs. (author)

  13. Influencia de Las Cargas Térmicas Sobre Flujos de Aire Generados en Una Habitacíon

    DEFF Research Database (Denmark)

    Olmedo, Inés; Ruiz de Adana Santiago, Manuel; Nielsen, Peter V.

    2011-01-01

    El flujo de aire en el interior de un local generado con un sistema de ventilación y difusión de aire puede verse afectado por las cargas térmicas internas del local. En este trabajo, se estudia la influencia de las cargas térmicas internas debidas a personas en el flujo de aire interior de un lo...

  14. Estudio de influencia de variables en la polimerización de bisfenol-acetofenona con difenilcarbonato

    OpenAIRE

    Ginestá Anzola, Anahí

    2008-01-01

    El enfoque de este estudio consiste en determinar experimentalmente la influencia que las distintas variables de operación (temperatura, concentración del catalizador y relación entre reactantes)ejercen en el procesol de policondensación entre el bisfenol acetofenona (AP) y el DPC, para que de esta manera puedan obtenerse las constantes cinéticas de esta reacción. Escuela Técnica Superior de Ingeniería Industrial

  15. Cambios espaciales y su influencia en la configuración territorial de Aguazul y Tauramena 1974–2005

    Directory of Open Access Journals (Sweden)

    Claudia Yolima Devia Acosta

    2011-09-01

    una periodización basada en el cambio en las actividades económicas y en los cambios político-administrativos en la configuración territorial de estos municipios. El artículo centra el análisis en la influencia de la actividad petrolera en la región, y en su capacidad directa e indirecta de transformar el territorio.

  16. Celos y violencia en alumnos de enseñanza secundaria. Influencia de los estilos educativos familiares

    OpenAIRE

    Aymerich Navarro, Mª del Milagro

    2016-01-01

    El objetivo de la tesis consiste en establecer la relación entre los celos en la adolescencia y la influencia de los estilos educativos familiares a la hora de explicar la violencia entre iguales, las reacciones emocionales y las conductas desajustadas de los adolescentes. Las reacciones emocionales se miden con las variables: celos, ansiedad y hostilidad. En cuanto a las reacciones conductuales se maneja como variable el bullying o victimización entre iguales. Con respecto a la variable e...

  17. Effect of Alpha-Particle Irradiation on Brain Glycogen in the Rat

    Science.gov (United States)

    Wolfe, L. S.; Klatzo, Igor; Miquel, Jaime; Tobias, Cornelius; Haymaker, Webb

    1962-01-01

    The studies of Klatzo, Miquel, Tobias and Haymaker (1961) have shown that one of the earliest and most sensitive indications of the effects of alpha-particle irradiation on rat bran is the appearance of glycogen granules mainly in the neuroglia of the exposed area of the brain. Periodic acid-Schiff (PAS) positive, alpha-amylase soluble granules were demonstrated within 12 hr after irradiation, preceding by approximately 36 hr the first microscopically detectable vascular permeability disturbances, as shown by the fluorescein labeled serum protein technique. These studies suggested that the injurious effects of alpha-particle energy were on cellular elements primarily, according to the physical properties and distribution of the radiation in the tissue, and that the vascular permeability disturbances played a secondary role in pathogenesis. The purpose of this study was to correlate the histochemical observations on glycogen with a quantitative assessment of the glycogen in the irradiated brain tissue. It is felt that such a study may contribute to the understanding of radiation injury at the molecular level. A practical aspect of this problem is that the information on biological radiation effects due to accelerated particles from the cyclotron source, is employed in this study, is applicable to radiation from cosmic particles both in free space and entrapped in the Van Allen belts.

  18. Alpha particle induced DNA damage and repair in normal cultured thyrocytes of different proliferation status

    Energy Technology Data Exchange (ETDEWEB)

    Lyckesvärd, Madeleine Nordén, E-mail: madeleine.lyckesvard@oncology.gu.se [Department of Oncology, Sahlgrenska Academy, University of Gothenburg (Sweden); Delle, Ulla; Kahu, Helena [Department of Oncology, Sahlgrenska Academy, University of Gothenburg (Sweden); Lindegren, Sture [Department of Radiation Physics, Sahlgrenska Academy, University of Gothenburg (Sweden); Jensen, Holger [The PET and Cyclotron Unit Copenhagen University Hospital, Rigshospitalet (Denmark); Bäck, Tom [Department of Radiation Physics, Sahlgrenska Academy, University of Gothenburg (Sweden); Swanpalmer, John [Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg (Sweden); Elmroth, Kecke [Department of Oncology, Sahlgrenska Academy, University of Gothenburg (Sweden)

    2014-07-15

    Highlights: • We study DNA damage response to low-LET photons and high-LET alpha particles. • Cycling primary thyrocytes are more sensitive to radiation than stationary cells. • Influence of radiation quality varies due to cell cycle status of normal cells. • High-LET radiation gives rise to a sustained DNA damage response. - Abstract: Childhood exposure to ionizing radiation increases the risk of developing thyroid cancer later in life and this is suggested to be due to higher proliferation of the young thyroid. The interest of using high-LET alpha particles from Astatine-211 ({sup 211}At), concentrated in the thyroid by the same mechanism as {sup 131}I [1], in cancer treatment has increased during recent years because of its high efficiency in inducing biological damage and beneficial dose distribution when compared to low-LET radiation. Most knowledge of the DNA damage response in thyroid is from studies using low-LET irradiation and much less is known of high-LET irradiation. In this paper we investigated the DNA damage response and biological consequences to photons from Cobolt-60 ({sup 60}Co) and alpha particles from {sup 211}At in normal primary thyrocytes of different cell cycle status. For both radiation qualities the intensity levels of γH2AX decreased during the first 24 h in both cycling and stationary cultures and complete repair was seen in all cultures but cycling cells exposed to {sup 211}At. Compared to stationary cells alpha particles were more harmful for cycling cultures, an effect also seen at the pChk2 levels. Increasing ratios of micronuclei per cell nuclei were seen up to 1 Gy {sup 211}At. We found that primary thyrocytes were much more sensitive to alpha particle exposure compared with low-LET photons. Calculations of the relative biological effectiveness yielded higher RBE for cycling cells compared with stationary cultures at a modest level of damage, clearly demonstrating that cell cycle status influences the relative

  19. Automated personnel radiation monitor

    International Nuclear Information System (INIS)

    Sterling, S.G.

    1981-01-01

    An automated Personnel Low-Level Radiation Portal Monitor has been developed by UNC Nuclear Industries, Inc. It is micro-computer controlled and uses nineteen large gas flow radiation detectors. By employing a micro-computer, sophisticated mathematical analysis is used on the detector informational data base to determine the statistical probability of contamination. This system provides for: (1) Increased sensitivity to point source contamination; (2) Real time background level compensation before and during Portal occupancy; (3) Variable counting periods as necessary to provide a significant statistical probability of contamination; (4) Continuous self-testing of system components, detector operability and sensitivity; and (5) Multiple modes of operation allowing the operator/owner control from continuous walk-through (for SNM detection at gates) to complete whole body counts (at step-off points from radiation zones). Sr-90 sources of .005 uCi can be detected from the hands and feet with a 90% confidence level, less than .1% false alarm rate with background levels up to 0.1 mR/hr. For the occupants periphery adjacent to the detectors, a sensitivity of .01 uCi is readily attainable. Alpha particle detection is legitimately available on hands, due to close proximity detection and thin Mylar detector cover techniques

  20. Automated personnel radiation monitor

    Energy Technology Data Exchange (ETDEWEB)

    Sterling, S.G.

    1981-06-01

    An automated Personnel Low-Level Radiation Portal Monitor has been developed by UNC Nuclear Industries, Inc. It is micro-computer controlled and uses nineteen large gas flow radiation detectors. By employing a micro-computer, sophisticated mathematical analysis is used on the detector informational data base to determine the statistical probability of contamination. This system provides for: (1) Increased sensitivity to point source contamination; (2) Real time background level compensation before and during Portal occupancy; (3) Variable counting periods as necessary to provide a significant statistical probability of contamination; (4) Continuous self-testing of system components, detector operability and sensitivity; and (5) Multiple modes of operation allowing the operator/owner control from continuous walk-through (for SNM detection at gates) to complete whole body counts (at step-off points from radiation zones). Sr-90 sources of .005 uCi can be detected from the hands and feet with a 90% confidence level, less than .1% false alarm rate with background levels up to 0.1 mR/hr. For the occupants periphery adjacent to the detectors, a sensitivity of .01 uCi is readily attainable. Alpha particle detection is legitimately available on hands, due to close proximity detection and thin Mylar detector cover techniques.

  1. Electromagnetic radiation optimum neutralizer

    International Nuclear Information System (INIS)

    Smirnov, Igor

    2002-01-01

    This particular article relates to subtle electrical effects, and provides some evidence of a fundamental nature on how subtle low frequency electromagnetic fields might be utilized to protect human body against harmful effects of high frequencies electromagnetic radiation. I have focused my efforts on definite polar polymer compound named EMRON which is patented in the USA. This polar polymer compound can be excited by external high frequencies electromagnetic fields to generate subtle low frequency oscillations that are beneficial for cellular life structures. This concept is based on the possibility of existence of resonance phenomenon between polar polymers and biopolymers such as proteins, nucleic acids, lipids, etc. Low frequency patterns generated by defined polar polymer compound can interact with biostructures and transmit the signals that support and improve cellular functions in the body. The mechanism of this process was confirmed by number of studies. The animal (including human) brain is affected by electromagnetic waves to the extent that production of Alpha or Theta waves can be directly induced into brain by carrying an ELF (extremely low frequency, 5-12 Hz) signal on a microwave carrier frequency. EMRON does not reduce the power of electromagnetic fields. It 'shields' the cellular structures of the body against the harmful effects of EMR. The radiation is still entering the body but the neutralizing effect of EMRON renders the radiation harmless

  2. Radiation practices. Annual report 2011

    Energy Technology Data Exchange (ETDEWEB)

    Rantanen, E. (ed.)

    2012-09-15

    1791 safety licences for the use of radiation were current at the end of 2011. 1702 responsible parties were engaged in notifiable licence-exempt dental X-ray activities. Use of radiation was controlled through regular inspections performed at places of use, test packages sent by post to dental X-ray facilities and maintenance of the Dose Register. Radiation safety guides were also published and research was conducted in support of regulatory control. The Radiation and Nuclear Safety Authority (STUK) conducted 575 inspections of licensed practices in 2011. 633 repair orders and recommendations were issued in the course of inspections. A total of nearly 11 700 workers were subject to individual monitoring in 2011 and about 143 000 dose entries were made in the Dose Register maintained by STUK. Regulatory control of natural radiation focused on radon at workplaces and exposure of aircrews to cosmic radiation. 166 workplaces including a total of 288 work areas were subject to radon monitoring during 2011. Just over 3600 cockpit and cabin crew members were monitored for exposure to cosmic radiation. STUK was involved in four ionizing radiation research projects, and also took part in an international expert group evaluation of STUK research activities. New alpha and beta sources were procured for metrological activities and a Co-60 irradiation device procured in 2010 was installed and taken into use. Calibration and testing services continued as in previous years. Regulatory control of the use of non-ionizing radiation in 2011 focused particularly on mobile phones, sunbeds and lasers. Orders were issued to 5 responsible parties to discontinue the use of tattoo removal lasers. 7 sunbed facilities were inspected and 10 on-site laser display inspections were performed. Five mobile phone types were tested in market surveillance of wireless communication devices. Non-ionizing radiation research activities were also subjected to the evaluation of STUK research activities

  3. Radiation practices. Annual report 2011

    International Nuclear Information System (INIS)

    Rantanen, E.

    2012-09-01

    1791 safety licences for the use of radiation were current at the end of 2011. 1702 responsible parties were engaged in notifiable licence-exempt dental X-ray activities. Use of radiation was controlled through regular inspections performed at places of use, test packages sent by post to dental X-ray facilities and maintenance of the Dose Register. Radiation safety guides were also published and research was conducted in support of regulatory control. The Radiation and Nuclear Safety Authority (STUK) conducted 575 inspections of licensed practices in 2011. 633 repair orders and recommendations were issued in the course of inspections. A total of nearly 11 700 workers were subject to individual monitoring in 2011 and about 143 000 dose entries were made in the Dose Register maintained by STUK. Regulatory control of natural radiation focused on radon at workplaces and exposure of aircrews to cosmic radiation. 166 workplaces including a total of 288 work areas were subject to radon monitoring during 2011. Just over 3600 cockpit and cabin crew members were monitored for exposure to cosmic radiation. STUK was involved in four ionizing radiation research projects, and also took part in an international expert group evaluation of STUK research activities. New alpha and beta sources were procured for metrological activities and a Co-60 irradiation device procured in 2010 was installed and taken into use. Calibration and testing services continued as in previous years. Regulatory control of the use of non-ionizing radiation in 2011 focused particularly on mobile phones, sunbeds and lasers. Orders were issued to 5 responsible parties to discontinue the use of tattoo removal lasers. 7 sunbed facilities were inspected and 10 on-site laser display inspections were performed. Five mobile phone types were tested in market surveillance of wireless communication devices. Non-ionizing radiation research activities were also subjected to the evaluation of STUK research activities

  4. Influencia del carbono y el cromo en el comportamiento tribológico de aleaciones férreas

    Directory of Open Access Journals (Sweden)

    García, A.

    2005-12-01

    Full Text Available This study compares the abrasive wear resistance of a carbon steel, used in the linings of coal mills, and ferrous alloys with different chromium and carbon content. It also analyses the influence of chromium and carbon content on mechanical properties, such as hardness, and microstructure. The abrasive wear resistance of the different materials was determined by means of ASTM G 105, "Standard Test Method for Conducting Wet Sand/Rubber Wheel Abrasion Test". A blasting test was used to study erosive wear resistance.

    En este estudio se analiza la influencia, en las propiedades tribológicas, del contenido en carbono para distintas aleaciones férreas con similares contenidos en cromo, así como la influencia del cromo cuando el contenido en carbono es semejante. También, se analizó la influencia de estos elementos en propiedades como la dureza y en la microestructura de las aleaciones. Para el estudio tribológico se llevaron a cabo dos ensayos, el ensayo descrito en la norma ASTM G105: Standard Test Method for Conducting Wet Sand/Rubber Wheel Abrasion Test y ensayos de chorreo.

  5. Entretenimiento, espiritualidad, familia y su relación con la influencia de pares en el consumo

    Directory of Open Access Journals (Sweden)

    Rolando Salazar Sarmiento

    2015-01-01

    Full Text Available El presente estudio fue una investigación de tipo exploratorio quantitativa. Examina la relación entre el uso de drogas en estudiantes universitarios de una universidad en Bogotá, Colombia y la influencia del grupo de pares, en torno al efecto moderador de factores socio-culturales como las relaciones familiares, el entretenimiento y la espiritualidad en dicho consumo. La muestra non probabilistica fue conformada por 350 estudiantes. El 89,4% de los jóvenes encuestados reportaran que consumen drogas ilícitas y el 82,2% aceptaran la influencia que los pares en este tipo de conductas. Los más altos consumos se presentan en alcohol con un 91,1% y tabaco con un 37,4%, las drogas de más bajo consumo son la cocaína y las anfetaminas. El consumo de drogas en estudiantes presenta índices elevados, y la influencia de los grupos entre los jóvenes es determinante de muchos de sus comportamientos.

  6. Determination of alpha_s using jet cross section parameterizations at hadron colliders

    CERN Document Server

    Stenzel, H

    2001-01-01

    Precise measurements of the single inclusive jet cross section have been performed by the TEVATRON experiments and will be provided by the LHC experiments extending to larger values of transverse energy. Theoretical predictions of this observable at NLO in perturbative QCD depend both on the PDF parameterization set and on the value of the strong coupling constant alpha_s. In this paper the dependence of the jet cross section on alpha_s is investigated. A method is presented to extract alpha_s(E_T) from a cross section measurement based on a parameterization of the alpha_s dependence. Systematic uncertainties and the E_T-range of applicability are discussed. A comparative study is performed between the case of ppbar at sqrt{s}=1.8 TeV (TEVATRON) and pp scattering at sqrt{s}=14 TeV (LHC).

  7. Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

    Energy Technology Data Exchange (ETDEWEB)

    Lochter, Andre; Navre, Marc; Werb, Zena; Bissell, Mina J

    1998-06-29

    Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions of integrins during tumor cell invasion.

  8. Mapping High-Velocity H-alpha and Lyman-alpha Emission from Supernova 1987A

    Science.gov (United States)

    France, Kevin; McCray, Richard; Fransson, Claes; Larsson, Josefin; Frank, Kari A.; Burrows, David N.; Challis, Peter; Kirshner, Robert P.; Chevalier, Roger A.; Garnavich, Peter; hide

    2015-01-01

    We present new Hubble Space Telescope images of high-velocity H-alpha and Lyman-alpha emission in the outer debris of SN 1987A. The H-alpha images are dominated by emission from hydrogen atoms crossing the reverse shock. For the first time we observe emission from the reverse shock surface well above and below the equatorial ring, suggesting a bipolar or conical structure perpendicular to the ring plane. Using the H-alpha imaging, we measure the mass flux of hydrogen atoms crossing the reverse shock front, in the velocity intervals (-7,500 < V(sub obs) < -2,800 km/s) and (1,000 < V(sub obs) < 7,500 km/s), ?M(sub H) = 1.2 × 10(exp -3) M/ y. We also present the first Lyman-alpha imaging of the whole remnant and new Chandra X-ray observations. Comparing the spatial distribution of the Lyman-alpha and X-ray emission, we observe that the majority of the high-velocity Lyman-alpha emission originates interior to the equatorial ring. The observed Lyman-alpha/H-alpha photon ratio, R(L-alpha/H-alpha) approx. = 17, is significantly higher than the theoretically predicted ratio of approx. = 5 for neutral atoms crossing the reverse shock front. We attribute this excess to Lyman-alpha emission produced by X-ray heating of the outer debris. The spatial orientation of the Lyman-alpha and X-ray emission suggests that X-ray heating of the outer debris is the dominant Lyman-alpha production mechanism in SN 1987A at this phase in its evolution.

  9. Radiation in dwellings and cancer in children

    International Nuclear Information System (INIS)

    Stjernfeldt, M.; Samuelsson, L.; Ludvigsson, J.

    1987-01-01

    Indoor radiation, especially radon exposure, has been in focus in the public domain during the past several years. The growing concern among parents of children with cancer possibly having high radiation levels in their homes led us to study the levels of gamma- and alpha-radiation levels in the homes of a group of children in the county of Ostergoetland. The indoor concentration of alpha-emitting radon daughters was measured by a high-voltage method. The gamma activity was measured with a standard detector scintillation meter. The yearly average for radon-daughter concentration in both cases (57 Bq/m3) and controls (61 Bq/m3) corresponds fairly well with the national average of 53 Bq/m3. The yearly average for gamma radiation (cases 0.37 mGy, controls 0.36 mGy) is much lower than the permissible upper level in dwellings (2.5 mGy/year). The values seem to be of the same order as the subtracted cosmic radiation, which is 0.24-0.26 mGy. No appreciable difference could thus be found between cases and controls either from gamma radiation or radon-daughter exposure. We cannot from our study rule out the possibility of an effect of low-level radiation in susceptible individuals, but it seems clear that children who get cancer do not live in more radioactive homes than other children

  10. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with the design and measurement of physical parameters used in theory or to support biological experiments. The radiation biophysics program tests and uses the theoretical developments for experimental design, and provides information for further theoretical development through experiments on cellular systems

  11. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with design and measurement of those physical parameters used in the theory or to support biological experiments. The radiation biophysics program tests and makes use of the theoretical developments for experimental design. Also, this program provides information for further theoretical development through experiments on cellular systems

  12. Atoms, Radiation, and Radiation Protection

    CERN Document Server

    Turner, James E

    2007-01-01

    Atoms, Radiation, and Radiation Protection offers professionals and advanced students a comprehensive coverage of the major concepts that underlie the origins and transport of ionizing radiation in matter. Understanding atomic structure and the physical mechanisms of radiation interactions is the foundation on which much of the current practice of radiological health protection is based. The work covers the detection and measurement of radiation and the statistical interpretation of the data. The procedures that are used to protect man and the environment from the potential harmful effects of

  13. Antioxidant Tocols as Radiation Countermeasures (Challenges to be Addressed to Use Tocols as Radiation Countermeasures in Humans

    Directory of Open Access Journals (Sweden)

    Ujwani Nukala

    2018-02-01

    Full Text Available Radiation countermeasures fall under three categories, radiation protectors, radiation mitigators, and radiation therapeutics. Radiation protectors are agents that are administered before radiation exposure to protect from radiation-induced injuries by numerous mechanisms, including scavenging free radicals that are generated by initial radiochemical events. Radiation mitigators are agents that are administered after the exposure of radiation but before the onset of symptoms by accelerating the recovery and repair from radiation-induced injuries. Whereas radiation therapeutic agents administered after the onset of symptoms act by regenerating the tissues that are injured by radiation. Vitamin E is an antioxidant that neutralizes free radicals generated by radiation exposure by donating H atoms. The vitamin E family consists of eight different vitamers, including four tocopherols and four tocotrienols. Though alpha-tocopherol was extensively studied in the past, tocotrienols have recently gained attention as radiation countermeasures. Despite several studies performed on tocotrienols, there is no clear evidence on the factors that are responsible for their superior radiation protection properties over tocopherols. Their absorption and bioavailability are also not well understood. In this review, we discuss tocopherol’s and tocotrienol’s efficacy as radiation countermeasures and identify the challenges to be addressed to develop them into radiation countermeasures for human use in the event of radiological emergencies.

  14. Direct binding of syndecan-4 cytoplasmic domain to the catalytic domain of protein kinase C alpha (PKC alpha) increases focal adhesion localization of PKC alpha

    DEFF Research Database (Denmark)

    Lim, Ssang-Taek; Longley, Robert L; Couchman, John R

    2003-01-01

    alpha. Full-length PKC alpha weakly interacted with 4V by yeast two-hybrid assays, but PKC alpha constructs that lack the pseudosubstrate region or constructs of the whole catalytic domain interacted more strongly. A mutated 4V sequence (4V(YF): LGKKPIFKK) did not interact with PKC alpha, indicating...

  15. Increased virulence and competitive advantage of a/alpha over a/a or alpha/alpha offspring conserves the mating system of Candida albicans.

    Science.gov (United States)

    Lockhart, Shawn R; Wu, Wei; Radke, Joshua B; Zhao, Rui; Soll, David R

    2005-04-01

    The majority of Candida albicans strains in nature are a/alpha and must undergo homozygosis to a/a or alpha/alpha to mate. Here we have used a mouse model for systemic infection to test the hypothesis that a/alpha strains predominate in nature because they have a competitive advantage over a/a and alpha/alpha offspring in colonizing hosts. Single-strain injection experiments revealed that a/alpha strains were far more virulent than either their a/a or alpha/alpha offspring. When equal numbers of parent a/alpha and offspring a/a or alpha/alpha cells were co-injected, a/alpha always exhibited a competitive advantage at the time of extreme host morbidity or death. When equal numbers of an engineered a/a/alpha2 strain and its isogenic a/a parent strain were co-injected, the a/a/alpha2 strain exhibited a competitive advantage at the time of host morbidity or death, suggesting that the genotype of the mating-type (MTL) locus, not associated genes on chromosome 5, provides a competitive advantage. We therefore propose that heterozygosity at the MTL locus not only represses white-opaque switching and genes involved in the mating process, but also affects virulence, providing a competitive advantage to the a/alpha genotype that conserves the mating system of C. albicans in nature.

  16. Influencia do indice de massa corporal no equilibrio e na configuracao plantar em obesos adultos

    Directory of Open Access Journals (Sweden)

    Liu Chiao Yi

    2014-01-01

    Full Text Available INTRODUÇÃO: A obesidade é uma doença crônica degenerativa multifatorial que pode levar a alterações do sistema musculoesquelético, como mudança do centro de gravidade e sobrecarga mecânica sobre os membros inferiores. OBJETIVOS: Correlacionar o índice de massa corporal (IMC com o equilíbrio corporal e verificar associação entre o IMC e a configuração plantar. MÉTODOS: Foram avaliados 30 obesos, de ambos os gêneros, com IMC maior ou igual a 30 Kg/m². Inicialmente, os voluntários foram submetidos às avaliações de medidas antropométricas a fim de calcular o valor do IMC. Em seguida, foram submetidos ao teste de equilíbrio corporal estático Balance Error Scoring System (BESS e a plantigrafia para a identificação da impressão plantar. Por meio do método de Viladot, os voluntários foram classificados em grupos: pé plano (GPP, pé cavo (GPC e pé neutro (GPN. A correlação entre as variáveis IMC e BESS foi calculada por meio do coeficiente de correlação linear de Pearson e associação entre o IMC e a configuração plantar foi realizada por meio da análise de variância (Anova. Para todas as análises, nível de significância considerado foi p < 0,05. RESULTADOS: Os valores da correlação entre o IMC e o BESS foram r = - 0,1 e p = 0,59. Os valores da associação do IMC entre GPN - GPP; GPN - GPC; GPP - GPC foram respectivamente: p = 0,76; p = 0,001; p = 0,07. CONCLUSÃO: O índice de massa corporal de adultos obesos não influencia o equilíbrio corporal, porém influencia na configuração plantar.

  17. Determination of alpha particle detection efficiency of an imaging plate (IP) detector

    International Nuclear Information System (INIS)

    Rahman, N.M; Iida, Takao; Yamazawa, Hiromi; Moriizumi, Jun

    2006-01-01

    In order to determine the detection efficiency of the imaging plate (IP) detector, the true radioactivity of the alpha particles, which sampled in the collection media, should be known. The true radioactivity could be accurately predicted with the help of the reference alpha spectrometer measurement. The detection efficiency calculated for the IP was estimated with the theoretical curve and the experimental data. It is assumed that the air sample contained the decay products of both 222 Rn and 220 Rn series, the most significant sources of alpha particles. The present study estimated the detection efficiency of the IP as 39.3% with an uncertainty of 2.9 that is well enough to confirm the future use of the IP as a radiation detector. Experimental materials and methods are described. (S.Y.)

  18. NMR Metabolomics in Ionizing Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jian Z.; Xiao, Xiongjie; Hu, Mary Y.

    2016-09-08

    Ionizing radiation is an invisible threat that cannot be seen, touched or smelled and exist either as particles or waves. Particle radiation can take the form of alpha, beta or neutrons, as well as high energy space particle radiation such as high energy iron, carbon and proton radiation, etc. (1) Non-particle radiation includes gamma- and x-rays. Publically, there is a growing concern about the adverse health effects due to ionizing radiation mainly because of the following facts. (a) The X-ray diagnostic images are taken routinely on patients. Even though the overall dosage from a single X-ray image such as a chest X-ray scan or a CT scan, also called X-ray computed tomography (X-ray CT), is low, repeated usage can cause serious health consequences, in particular with the possibility of developing cancer (2, 3). (b) Human space exploration has gone beyond moon and is planning to send human to the orbit of Mars by the mid-2030s. And a landing on Mars will follow.

  19. Radiation effects in the lung

    International Nuclear Information System (INIS)

    Coggle, J.E.; Lambert, B.E.; Moores, S.R.

    1986-01-01

    This article outlines the principles of radiobiology that can explain the time of onset, duration, and severity of the complex reactions of the lung to ionizing radiation. These reactions have been assayed biochemically, cell kinetically, physiologically, and pathologically. Clinical and experimental data are used to describe the acute and late reactions of the lung to both external and internal radiation including pneumonitis, fibrosis and carcinogenesis. Acute radiation pneumonitis, which can be fatal, develops in both humans and animals within 6 months of exposure to doses greater than or equal to 8 Gy of low LET radiation. It is divisible into a latent period lasting up to 4 weeks; an exudative phase (3-8 weeks) and with an acute pneumonitic phase between 2 and 6 months. There is much evidence to suggest that pneumonitis is an epithelial reaction and some evidence to suggest that this early damage may not be predictive of late fibrosis. However, despite detailed work on collagen metabolism, the pathogenesis of radiation fibrosis remains unknown. The data on radiation-induced pulmonary cancer, both in man and experimental animals from both external and internal irradiation following the inhalation of both soluble and insoluble alpha and beta emitting radionuclides are reviewed. 312 references. (Abstract Truncated)

  20. Alpha intrusion on ovenight polysomnogram

    Directory of Open Access Journals (Sweden)

    Nahapetian R

    2014-06-01

    Full Text Available No abstract available. Article truncated after 150 words. A 30 year-old Army veteran with a past medical history significant for chronic lumbar back pain stemming from a fall-from-height injury sustained in 2006 was referred to the sleep laboratory for evaluation of chronic fatigue and excessive daytime hypersomnolence. His Epworth sleepiness scale score was 16. He denied a history of snoring and witnessed apnea. Body Mass Index (BMI was 25.7 kg/m2. His main sleep related complaints were frequent nocturnal arousals, poor sleep quality, un-refreshing sleep, prolonged latency to sleep onset, and nightmares. An In-lab attended diagnostic polysomnogram was performed. Sleep efficiency was reduced (73% and overall arousal index was not significantly elevated (3.2 events/hour. The sleep study showed rapid eye movement (REM related sleep disordered breathing that did not meet diagnostic criteria for sleep apnea. There was no evidence for period limb movement disorder. However, the study was significant for alpha wave intrusion in stage N2 non-REM and stage ...

  1. Diabetes and alpha lipoic acid

    Directory of Open Access Journals (Sweden)

    Issy eLaher

    2011-11-01

    Full Text Available Diabetes mellitus is a multi-faceted metabolic disorder where there is increased oxidative stress that contributes to the pathogenesis of this debilitating disease. This has prompted several investigations into the use of antioxidants as a complementary therapeutic approach. Alpha lipoic acid, a naturally occurring dithiol compound which plays an essential role in mitochondrial bioenergetic reactions, has gained considerable attention as an antioxidant for use in managing diabetic complications. Lipoic acid quenches reactive oxygen species, chelates metal ions, and reduces the oxidized forms of other antioxidants such as vitamin C, vitamin E and glutathione. It also boosts antioxidant defense system through Nrf2-mediated antioxidant gene expression and by modulation of peroxisome proliferator activated receptors-regulated genes. ALA inhibits nuclear factor kappa B and activates AMPK in skeletal muscles, which in turn have a plethora of metabolic consequences. These diverse actions suggest that a lipoic acid acts by multiple mechanisms, many of which have only been uncovered recently. In this review we briefly summarize the known biochemical properties of lipoic acid and then discussed the oxidative mechanisms implicated in diabetic complications and the mechanisms by which lipoic acid may ameliorate these reactions. The findings of some of the clinical trials in which lipoic acid administration has been tested in diabetic patients during the last 10 years are summarized. It appears that the clearest benefit of lipoic acid supplementation is in patients with diabetic neuropathy.

  2. Diagnostics for PLX-alpha

    Science.gov (United States)

    Gilmore, Mark; Hsu, Scott

    2015-11-01

    The goal of the Plasma Liner eXperiment PLX-alpha at Los Alamos National Laboratory is to establish the viability of creating a spherically imploding plasma liner for MIF and HED applications, using a spherical array of supersonic plasma jets launched by innovative contoured-gap coaxial plasma guns. PLX- α experiments will focus in particular on establishing the ram pressure and uniformity scalings of partial and fully spherical plasma liners. In order to characterize these parameters experimentally, a suite of diagnostics is planned, including multi-camera fast imaging, a 16-channel visible interferometer (upgraded from 8 channels) with reconfigurable, fiber-coupled front end, and visible and VUV high-resolution and survey spectroscopy. Tomographic reconstruction and data fusion techniques will be used in conjunction with interferometry, imaging, and synthetic diagnostics from modeling to characterize liner uniformity in 3D. Diagnostic and data analysis design, implementation, and status will be presented. Supported by the Advanced Research Projects Agency - Energy - U.S. Department of Energy.

  3. Cortical Alpha Activity in Schizoaffective Patients

    Directory of Open Access Journals (Sweden)

    Mahdi Moeini

    2017-02-01

    Full Text Available Objective: Electrophysiological studies have identified abnormal oscillatory activities in the cerebral cortex in schizophrenia and mood disorders. Biological and pathophysiological evidence suggests specific deficits in serotonin (5-HT receptor function in schizoaffective disorder (SA, a clinical syndrome with characteristics of both schizophrenia and bipolar disorder. This study investigated alpha oscillations in patients with SA.Method: Electroencephalography was used to measure ongoing and evoked alpha oscillations in 38 adults meeting Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition (DSM–IV criteria for SA, and in 39 healthy controls.Results: Spontaneous alpha power of the participants with SA was significantly lower than that of healthy participants [F (1, 75 = 8.81, P < 0.01]. Evoked alpha activity was also decreased in SA compared to controls [F (1, 75 = 5.67, P = 0.025].Conclusion: A strong reduction of alpha power in the posterior regions may reflect abnormality in the thalamocortical circuits. It is shown that hypoxia and reduced cerebral blood flow is associated with reduced alpha activity among different regions of the brain. Therefore, it can be concluded that greatly decreased alpha activity, particularly in centro-parietal and occipital regions, is related to SA symptoms such as hallucinations.

  4. Lucid dreaming and alpha activity: a preliminary report.

    Science.gov (United States)

    Ogilvie, R D; Hunt, H T; Tyson, P D; Lucescu, M L; Jeakins, D B

    1982-12-01

    10 good dream recallers spent 2 nights in the sleep lab during which they were awakened 4 times per night from REM sleep, twice during their highest alpha activity in REM, and twice during low REM alpha. 5 were given alpha feedback training prior to sleep onset. Arousals from high alpha REM sleep yielded significantly higher lucidity ratings. Alpha feedback had no effect upon lucidity or REM alpha levels. Similarities between lucid dreams and meditative phenomena are discussed.

  5. Studying effects of Magnolol on alpha-particle induced bystander effects using PADC-film based dishes

    Energy Technology Data Exchange (ETDEWEB)

    Wong, T.P.W. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Tse, A.K.W.; Fong, W.F. [Research and Development Division, School of Chinese Medicine, Hong Kong Baptist University, Baptist University Road, Kowloon Tong (Hong Kong); Yu, K.N., E-mail: peter.yu@cityu.edu.h [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong)

    2009-10-15

    Radiation-induced bystander effect refers to the biological response found in cells (called bystander cells) which are not irradiated directly by ionizing radiation but are next to cells irradiated directly by ionizing radiation. In the present paper, the effects of Magnolol, an extract from the bark of Magnolia officinalis which is used as a traditional Chinese medicine, were studied on alpha-particle induced bystander effects. In our experiments, Chinese hamster ovary (CHO) cells were cultured in PADC-film based dishes and were irradiated with low fluences of alpha particles passing through the PADC films. The precise number of cells traversed or missed by alpha particles could be determined by studying the alpha-particle tracks developed on the PADC films upon subsequent chemical etching. TdT-mediated dUTP Nick-End Labeling (TUNEL) assay was employed to analyze the biological response of bystander cells in terms of DNA strand breaks. With the pretreatment of Magnolol, the DNA strand breaks in bystander cells were reduced, which showed that the alpha-particle induced bystander effects were suppressed with the presence of Magnolol. Since Magnolol is an antioxidant which can scavenge reactive oxygen species (ROS), our results give support to that ROS play a role in the bystander signal transmission in our experiments.

  6. How we can Transform the Constant Alpha Value into a Variable Function

    Energy Technology Data Exchange (ETDEWEB)

    Acosta P, C.F.; Sordi, G.M.A.A. [Instituto de Pesquisas Energeticas e Nucleares, Sao Paulo (Brazil)]. e-mail: cani@osite.com.br

    2006-07-01

    For the cost-benefit analysis used in the quantitative decision aiding techniques the alpha value is the aim of the question, because it is the alpha value that, directly or indirectly determines the analytical solution Y, consequently, the workers doses distribution involved with ionizing radiation source. Currently, each country adopts a single alpha value that can be linked to the annual gross product (GNP) per capita. Otherwise, the risks due to the ionizing radiation practices Y the ultimate objective, that is, to decrease the doses to admissible levels, are the same in any place of the world. In this case, it seems reasonable to think that the alpha value would be the same in every country. With this view, this paper has the objective to present, as suggestion, how it is possible to make a variable of the alpha value. To achieve this goal using a rigorous mathematical model, the protection options were linked by a curve selected among several curves that best fit in place of the straight line as the ICRP does. The curve selection was applied to the small uranium mine example provide by ICRP in publication number 55. Introducing a variable alpha value as function of the highest individual dose, their values will not depend on the GNP per capita anymore, but on the maximum individual dose distribution Y the length of time necessary to comprise, if possible, the aim of 1/10 of the annual dose limits for workers foreseen in the successive optimizations, that is, to range the individual dose zone considered acceptable. (Author)

  7. How we can Transform the Constant Alpha Value into a Variable Function

    International Nuclear Information System (INIS)

    Acosta P, C.F.; Sordi, G.M.A.A.

    2006-01-01

    For the cost-benefit analysis used in the quantitative decision aiding techniques the alpha value is the aim of the question, because it is the alpha value that, directly or indirectly determines the analytical solution Y, consequently, the workers doses distribution involved with ionizing radiation source. Currently, each country adopts a single alpha value that can be linked to the annual gross product (GNP) per capita. Otherwise, the risks due to the ionizing radiation practices Y the ultimate objective, that is, to decrease the doses to admissible levels, are the same in any place of the world. In this case, it seems reasonable to think that the alpha value would be the same in every country. With this view, this paper has the objective to present, as suggestion, how it is possible to make a variable of the alpha value. To achieve this goal using a rigorous mathematical model, the protection options were linked by a curve selected among several curves that best fit in place of the straight line as the ICRP does. The curve selection was applied to the small uranium mine example provide by ICRP in publication number 55. Introducing a variable alpha value as function of the highest individual dose, their values will not depend on the GNP per capita anymore, but on the maximum individual dose distribution Y the length of time necessary to comprise, if possible, the aim of 1/10 of the annual dose limits for workers foreseen in the successive optimizations, that is, to range the individual dose zone considered acceptable. (Author)

  8. Radiation physics

    International Nuclear Information System (INIS)

    Robles, Ana Maria

    1994-01-01

    A brief historical review of radioactivity, nuclear physics, atomic nucleus, nuclear models,nuclear instability, mass defect, nuclear transmutations, radioactivity phenomenon, Batemand equations, decay constants, half life, mean life, des integration rates,units.Alpha, Beta and gamma decay, other less probably encountered decay modes.Bibliography

  9. Radiation carcinogenesis

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1976-01-01

    The risk of iatrogenic tumors with radiation therapy is so outweighed by the benefit of cure that estimates of risk have not been considered necessary. However, with the introduction of chemotherapy, combined therapy, and particle radiation therapy, the comparative risks should be examined. In the case of radiation, total dose, fractionation, dose rate, dose distribution, and radiation quality should be considered in the estimation of risk. The biological factors that must be considered include incidence of tumors, latent period, degree of malignancy, and multiplicity of tumors. The risk of radiation induction of tumors is influenced by the genotype, sex, and age of the patient, the tissues that will be exposed, and previous therapy. With chemotherapy the number of cells at risk is usually markedly higher than with radiation therapy. Clearly the problem of the estimation of comparative risks is complex. This paper presents the current views on the comparative risks and the importance of the various factors that influence the estimation of risk

  10. Radiation acoustics

    CERN Document Server

    Lyamshev, Leonid M

    2004-01-01

    Radiation acoustics is a developing field lying at the intersection of acoustics, high-energy physics, nuclear physics, and condensed matter physics. Radiation Acoustics is among the first books to address this promising field of study, and the first to collect all of the most significant results achieved since research in this area began in earnest in the 1970s.The book begins by reviewing the data on elementary particles, absorption of penetrating radiation in a substance, and the mechanisms of acoustic radiation excitation. The next seven chapters present a theoretical treatment of thermoradiation sound generation in condensed media under the action of modulated penetrating radiation and radiation pulses. The author explores particular features of the acoustic fields of moving thermoradiation sound sources, sound excitation by single high-energy particles, and the efficiency and optimal conditions of thermoradiation sound generation. Experimental results follow the theoretical discussions, and these clearl...

  11. Anomalous atomic volume of alpha-Pu

    DEFF Research Database (Denmark)

    Kollar, J.; Vitos, Levente; Skriver, Hans Lomholt

    1997-01-01

    We have performed full charge-density calculations for the equilibrium atomic volumes of the alpha-phase light actinide metals using the local density approximation (LDA) and the generalized gradient approximation (GGA). The average deviation between the experimental and the GGA atomic radii is 1.......3%. The comparison between the LDA and GGA results show that the anomalously large atomic volume of alpha-Pu relative to alpha-Np can be ascribed to exchange-correlation effects connected with the presence of low coordinated sites in the structure where the f electrons are close to the onset of localization...

  12. Alpha spectral analysis via artificial neural networks

    International Nuclear Information System (INIS)

    Kangas, L.J.; Hashem, S.; Keller, P.E.; Kouzes, R.T.; Troyer, G.L.

    1994-10-01

    An artificial neural network system that assigns quality factors to alpha particle energy spectra is discussed. The alpha energy spectra are used to detect plutonium contamination in the work environment. The quality factors represent the levels of spectral degradation caused by miscalibration and foreign matter affecting the instruments. A set of spectra was labeled with a quality factor by an expert and used in training the artificial neural network expert system. The investigation shows that the expert knowledge of alpha spectra quality factors can be transferred to an ANN system

  13. Production of alpha 1-proteinase inhibitor (human).

    Science.gov (United States)

    Hein, R H; Van Beveren, S M; Shearer, M A; Coan, M H; Brockway, W J

    1990-03-01

    A method for large scale isolation of alpha 1-proteinase inhibitor (alpha 1-PI) is described. This method employs waste Cohn Fraction IV-1 as the starting material and involves fractional precipitation with polyethylene glycol followed by ion exchange chromatography on diethylaminoethanol (DEAE)-Sepharose. The process also incorporates a ten hour, at 60 degrees C, heat-treatment step to reduce or eliminate the risk of transmission of viral disease. The final product, having a purity of approximately 60%, is freeze-dried. This preparation behaves almost identically to the alpha 1-PI in plasma and is suitable for replacement therapy in hereditary emphysema.

  14. Measurements of $\\alpha_s$ in $pp$ Collisions at the LHC

    CERN Document Server

    Warburton, Andreas; The ATLAS collaboration

    2015-01-01

    The coupling of the strong force, $\\alpha_s$, is deemed to be a fundamental parameter of Nature, and, beyond the quark masses, constitutes the only free parameter in the QCD Lagrangian. Provided is an overview of CERN Large Hadron Collider (LHC) measurements of $\\alpha_s(M_Z)$ evaluated at the $Z$-boson mass and of the running of $\\alpha_s(Q)$ as a function of energy-momentum transfer $Q$. The measurements were performed by the ATLAS and CMS Collaborations using proton-proton ($pp$) collisions with centre-of-mass energies of 7 TeV and data samples with time-integrated luminosities of up to 5 fb$^{-1}$. Four different categories of observable were used in the described extractions of $\\alpha_s$: inclusive jet cross sections, 3-jet to 2-jet inclusive cross-section ratios, 3-jet mass cross sections, and top-quark pair production cross sections. These results, which include the first NNLO measurement of $\\alpha_s$ at a hadron collider and the first determinations of $\\alpha_s$ at energy scales above 1 TeV, are co...

  15. A Quantitative Electrochemiluminescence Assay for Clostridium perfringens alpha toxin

    National Research Council Canada - National Science Library

    Merrill, Gerald A; Rivera, Victor R; Neal, Dwayne D; Young, Charles; Poli, Mark A

    2006-01-01

    .... Biotinylated antibodies to C. perfringens alpha toxin bound to streptavidin paramagnetic beads specifically immunoadsorbed soluble sample alpha toxin which subsequently selectively immunoadsorbed ruthenium (Ru...

  16. Hawking radiation

    Science.gov (United States)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

  17. Radiation protection

    International Nuclear Information System (INIS)

    1989-01-01

    A NRPB leaflet in the 'At-a-Glance' series explains in a simple but scientifically accurate way what radiation is, the biological effects and the relative sensitivity of different parts of the human body. The leaflet then discusses radiation protection principles, radiation protection in the UK and finally the effectiveness of this radiation protection as judged by a breakdown of the total dose received by an average person in the UK, a heavy consumer of Cumbrian seafood, an average nuclear industry worker and an average person in Cornwall. (UK)

  18. GRAVITATIONAL RADIATION

    Directory of Open Access Journals (Sweden)

    Metin SALTIK

    1996-03-01

    Full Text Available According to classical electromagnetic theory, an accelerated charge or system of charges radiates electromagnetic waves. In a radio transmitter antenna charges are accelerated along the antenna and release electromagnetic waves, which is radiated at the velocity of light in the surrounding medium. All of the radio transmitters work on this principle today. In this study an analogy is established between the principles by which accelerated charge systems markes radiation and the accelerated mass system, and the systems cousing gravitational radiation are investigated.

  19. Radiation medicine

    International Nuclear Information System (INIS)

    1991-01-01

    This booklet has been produced by UKAEA and the Marie Curie Memorial Foundation to give some basic information about what radiation is and how it is used in day to day diagnosis and treatment. It will be of interest to people undergoing treatment, their relatives and friends, and anyone who wants to know more about this important area. After a brief historical introduction the booklet explains what radiation is, the natural and man-made sources of radiation, how it is produced and how X-rays are used in medical diagnosis and treatment. The radiation protection measures taken and safety standards followed are mentioned. (author)

  20. High Energy K(alpha) Radiography Using High-intensity, Short-pulse Lasers

    Energy Technology Data Exchange (ETDEWEB)

    Park, H; Izumi, N; Key, M H; King, J A; Koch, J A; Landen, O L; Patel, P K; Price, D F; Remington, B A; Robey, H F; Snavely, R A; Tabak, M; Town, R J; Wickersham, J E; Stoeckl, C; Storm, M; Theobald, W; Chambers, D M; Eagelton, R; Goldsack, T; Clarke, R J; Heathcote, R; Giraldez, E; Nikroo, A; Steinman, D A; Stephens, R B; Zhang, B B

    2005-11-16

    We have performed experiments using Callisto, the Vulcan 100 TW and the Vulcan Petawatt high intensity lasers to understand the characteristics of high energy, K{alpha} x-ray sources and to implement workable radiography solutions at 20-100 keV. Our measurements show that the K{alpha} size from a simple foil target is larger than 60 {micro}m, far larger than the experiment resolution requirement. The total K{alpha} yield is independent of target thicknesses verifying that refluxing plays a major role in photon generation. Smaller radiating volumes emit brighter K{alpha} radiation. 1-D radiography experiments using small-edge-on foils resolved 10 {micro}m features with high contrast. We tested a variety of small volume 2-D point sources such as cones, wires, and embedded wires, measuring photon yields and comparing our measurements with predictions from hybrid-PIC LSP simulations. In addition to high-energy, high-resolution backlighters, future experiments will also need imaging detectors and diagnostic tools that are workable in the 20-100 keV energy range. An initial look at some of these detector issues is also presented.

  1. RETROSPECTIVE METHOD VALIDATION AND UNCERTAINTY ESTIMATION FOR ACTINIDES DETERMINATION IN EXCRETA BY ALPHA SPECTROMETRY.

    Science.gov (United States)

    Hernández, C; Sierra, I

    2016-09-01

    Two essential technical requirements of ISO 17025 guide for accreditation of testing and calibration laboratories are the validation of methods and the estimation of all sources of uncertainty that may affect the analytical result. Bioelimination Laboratory from Radiation Dosimetry Service of CIEMAT (Spain) uses alpha spectrometry to quantify alpha emitters (Pu, Am, Th, U and Cm isotopes) in urine and faecal samples from workers exposed to internal radiation. Therefore and as a step previous to achieving the ISO 17025 accreditation, the laboratory has performed retrospective studies based on the obtained results in the past few years to validate the analytical method. Uncertainty estimation was done identifying and quantifying all the contributions, and finally the overall combined standard uncertainty was calculated. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Induction of the lambda bacteriophage synthesis in Escherichia coli K 12 by polonium alpha rays

    International Nuclear Information System (INIS)

    Devoret, Raymond

    1958-06-01

    This research thesis reports the study of the inducing action of polonium alpha radiations in Escherichia Coli K 12 by using an external irradiation device. This work comprised the development of a method to spread bacteria in layer with a thickness less than 20 microns, and the measurement of the number of α particles falling on the irradiated surface. This measurement has been performed by using a nuclear emulsion and a simple photographic film. It appears that alpha radiations have an inducing action, and that at most 15 per cent of bacteria can be induced. The comparison of the induction curve with the survival curves of lysogen and sensitive stains shows that there is no abortive induction. Thus, it appears that this inducing action is not due to an indirect effect of the irradiated medium [fr

  3. INFLUENCIA DE LA LONGITUD DEL CONO DE UN CICLÓN SOBRE LAS VARIABLES DE FLUJO

    Directory of Open Access Journals (Sweden)

    Horacio A. Petit

    2012-01-01

    Full Text Available Los ciclones son separadores gas-polvo ampliamente empleados en la industria. Su eficiencia depende de las variables geométricas de diseño y de las condiciones de operación. En este trabajo se estudia el efecto de la longitud de la parte cónica sobre la eficiencia de recolección de polvo. Se realiza la simulación del flujo turbulento presente en los ciclones para analizar la distribución de velocidades tangenciales y determinar la caída de presión. Se utiliza el modelo LES (Large Eddy Simulation y se aplican las técnicas de fluidodinámica computacional (CFD: Computacional Fluid Dynamics. Empleando el modelo del número de vórtices para determinar la eficiencia fraccional, se pudo establecer que los ciclones con mayor largo de cono presentan mejor eficiencia de separación y menor caída de presión. Esto ocurre para cualquier diámetro de partícula y en todo el rango de temperaturas estudiado, siendo la influencia del largo del cono mayor para las menores temperaturas.

  4. Influencia de los Roles de Equipo en las Actividades del Desarrollador de Software

    Directory of Open Access Journals (Sweden)

    Elsa Estrada Guzmán

    2013-05-01

    Full Text Available Uno de los roles básicos en el proceso del software es precisamente el de desarrollador, también denominado ingeniero de software, cuyas actividades principales son: el análisis, diseño, programación y pruebas del producto a desarrollar. Estas actividades, dependiendo generalmente del tamaño del proyecto y de la metodología, pueden estar a cargo de diferentes personas o bien de un grupo de desarrolladores que en conjunto las llevan todas a cabo; en este último caso, estaríamos hablando de trabajo en equipo entre iguales o pares. Por otro lado, de acuerdo con la teoría de roles de equipo, las personas tienden a comportarse de manera regular en forma distintiva cuando colaboran, estas formas particulares de colaborar es probable que influyan en el desempeño del equipo de desarrolladores de software. En este documento se presenta un caso de estudio con la finalidad de entender la influencia de los roles de equipo en ciertas actividades involucradas en el proceso de desarrollo de software.

  5. La influencia de la Revolución Cultural en las mujeres chinas

    Directory of Open Access Journals (Sweden)

    María Gómez y Patiño

    2013-11-01

    Full Text Available Si todos los procesos de transición política influyen en la ciudadanía en general, las mujeres suelen sufrir sus consecuencias doblemente: primero, a título individual, y segundo, como mujer. La influencia que la Revolución Cultural tuvo en China persiste en la mentalidad y en la vida de las mujeres del país asiático emergente par excellence. Este artículo presenta diez entrevistas personales realizadas in situ, a mujeres de distintos orígenes, edades, estatus social y nivel cultural, cuya vida se vio afectada por uno de los procesos políticos más fuertes que la historia universal ha recogido. El análisis y la interpretación de estas entrevistas ofrecen una perspectiva inédita de su visión del mundo, así como un testimonio oral de ese capítulo de la historia.

  6. La influencia de los rasgos psicológicos en las actitudes hacia el empleo

    Directory of Open Access Journals (Sweden)

    Antonia Mercedes García Cabrera

    2008-01-01

    Full Text Available Esta investigación explica la influencia que el rasgo psicológico locus de control, conjuntamente con las variables que definen el capital humano de un país -género, edad y educación-, ejercen sobre las actitudes hacia el empleo en la República de Cabo Verde. De entre estos rasgos demográficos del individuo, el género es analizado más profundamente debido al interés actual por reducir las desigualdades en razón de género en el mercado laboral. Los 448 cuestionarios recabados muestran que, en este país, los atributos demográficos edad y nivel de estudios, así como el rasgo de personalidad locus de control, son importantes determinantes de las actitudes hacia el empleo de la población activa. Los resultados ofrecen las bases sobre las que redirigir las políticas de empleo en Cabo Verde para afrontar los puntos débiles que limitan el desarrollo del mercado de trabajo y amenazan la integración social.

  7. El fantasma del abstencionismo y la influencia mediática

    Directory of Open Access Journals (Sweden)

    Lic. Edith Barajas

    2001-01-01

    Full Text Available Nadie duda, en el inicio de un nuevo milenio, de la influencia y el impacto de los medios masivos de comunicación. La prensa, la radio, la televisión y, contemporáneamente Internet, juegan un papel clave en la nueva era de la humanidad, donde la paradoja es tener información a mansalva para un ser actual dominado por fenómenos como el cortoplacismo, los antimodelos, las guerras, el esoterismo, la hambruna, la religión y la violencia, todo englobado, a su vez, en una economía mundializada que rompe y descarna las fronteras de las naciones, y en donde los futurólogos citan las dos grandes vías: la era digital y la era biológica.En el llamado "control de masas", el medio masivo, especialmente el electrónico, desarrolla un actor importante dentro del mundo global, pues mantiene a la mayoría de la población concentrada en temas que no son precisamente los del orden de mayor interés (en nuestro país, podemos considerar el escándalo Trevi-Andrade como un elemento distractor, sobre los problemas que aquejan al país; es decir, la opinión pública se concentra en ese enfoque, antes de irse a lo medular

  8. Influencia del polvo del horno de cemento sobre plantas y animales

    Directory of Open Access Journals (Sweden)

    Pajenkamp, H.

    1963-06-01

    Full Text Available Not availableEl pretendido «polvo de cemento» de los alrededores de las fábricas no es de cemento, sino que se compone, en su mayor parte, de caliza molida muy fina. Es, por tanto, un producto intermedio de la fabricación del cemento. Sería mucho más correcto llamarle «polvo del horno de cemento». Continuamente alegan los agricultores que este «polvo del horno de cemento» es dañino para plantas y animales, y en los últimos años, para probar la validez de tales asertos, se han llevado a cabo numerosas investigaciones científicas para estudiar los efectos de este polvo. Estamos hoy día en posesión de una serie· de trabajos muy completos que dan una idea clara sobre el efecto del polvo del horno de cemento. Los animales domésticos útiles (por ejemplo: corderos, vacas de leche no sufren ningún perjuicio clínico, ninguna deficiencia de su estado general, a pesar de serie administradas grandes dosis de polvo. Los ensayos agrícolas con plantas útiles (avena, trébol, remolacha azucarera, pastos que han sido efectuados durante varios años, han demostrado que ni siquiera cantidades elevadas de polvo provocan perjuicios ni influencias nefastas sobre el crecimiento y sobre la recolección.

  9. La influencia del conocimiento político en las decisiones de voto

    Directory of Open Access Journals (Sweden)

    Marta FRAILE

    2007-01-01

    Full Text Available Este trabajo discute y compara dos lógicas explicativas del comportamiento electoral: el voto por resultados y el voto ideológico. En concreto, el trabajo pone a prueba uno de los principales supuestos de ambas teorías: que las reglas que guían las decisiones de voto de los ciudadanos son las mismas independientemente de su nivel de interés, conocimiento e información sobre los temas políticos. Para ello se analiza material empírico proveniente de encuestas postelectorales en cuatro democracias: España, Portugal, Hungría y Polonia. Los datos pertenecen al segundo módulo del programa de Estudio Comparado de Sistemas Electorales (CSES, 2005, que contiene información sobre el comportamiento electoral y el conocimiento político de los ciudadanos. Los resultados apuntan a que mientras la influencia del conocimiento político en la lógica del voto por resultados es clara y contundente, resulta mucho menos concluyente en el caso del voto ideológico. Todo ello sugiere que el control democrático de los gobiernos a través de la sanción de su rendimiento requiere unos niveles mínimos de conocimiento e información sobre la política por parte de la ciudadanía.

  10. Mejora de la calidad del acero obtenido por colada continua mediante influencias electrofísicas

    Directory of Open Access Journals (Sweden)

    Shklyar, V.

    1998-12-01

    Full Text Available Laboratory tests with tin smelted in a crucible and industrial tests with crude steel poured in moulds had been carried out. These metals were subjected to electrophysical influences. As a result of the applied electric field, it is observed in tin that during the solidification, the crystalization temperature and the solidification time are changed. Crystal growth in the electric field direction and an increase of the fracture limit in the steel ingot are observed.

    Se han realizado ensayos de laboratorio con estaño fundido en crisol y a escala industrial con acero líquido vertidos en moldes, sometiendo estos metales a influencias electrofísicas. Como resultado del campo aplicado, en el estaño se observa que durante la solidificación varía la temperatura de cristalización y el tiempo de solidificación. En el lingote de acero se observa un crecimiento de los cristales en dirección del campo eléctrico y un aumento del límite de rotura.

  11. Influencia de las diferentes etapas de procesamiento sobre la microestructura de dispositivos multicapa basados en PZT

    Directory of Open Access Journals (Sweden)

    Solera, E.

    2002-02-01

    Full Text Available A comparative study of the influence of both rheological and processing parameters on the microstructure and reliability of multilayer ceramic chips based on PZT has been conducted. The multilayer chips were obtained by tape casting. Viscosity measurements of different slurries with various solids content have been correlated with both the thickness and the green density of the casted layers. The critical points of the thermal treatments, organics burn-out and sintering, have been identified. The green microstructure of the layers and the final microstructure of the sintered chips have been studied by SEM.

    Se ha realizado un estudio comparativo de la influencia de los parámetros reológicos y de procesamiento sobre la microestructura y consistencia de chips multicapa de PZT obtenidos mediante un proceso de colado en cinta. Para ello se han realizado medidas de viscosidad de distintas barbotinas con diferente contenido en sólidos y su relación con el espesor y densidad en verde de las cintas obtenidas, se han identificado los puntos críticos del ciclo de quemado-sinterización y, mediante MEB se ha estudiado la microestructura en verde de las láminas coladas y la microestructura final de los chips multicapa fabricados.

  12. Influencia familiar sobre las actitudes ante el consumo de drogas en adolescentes españoles

    Directory of Open Access Journals (Sweden)

    María de la Villa Moral Jiménez

    2013-08-01

    Full Text Available En la cultura mediterránea la familia sigue siendo la agencia socializadora por excelencia, a pesar de diversos cambios referenciales y en la intensidad de los afectos, así como en los estilos disciplinares característicos de nuevas tipologías de familias postmodernas. La influencia y modelado familiar sobre las actitudes ante el consumo de sustancias psicoactivas en adolescentes está bien establecida en indicadores tales como experiencias paternas con las drogas, apego y supervisión parental, clima afectivo, dinámica sociofamiliar, etc. Nuestro objeto de estudio se centra en el análisis psicosocial de tales indicadores, así como en ofrecer un análisis diferencial de la valoración de la relación paterno-filial en relación con las actitudes ante el consumo de drogas en un colectivo de adolescentes españoles. Se ha confirmado una mayor permisividad actitudinal y menor concienciación ante los efectos dañinos de las drogas en los hijos de padres consumidores de sustancias psicoactivas tanto legales como ilegales. Se confirma la importancia psicosocial del Apoyo más valorado por los adolescentes que no consumen drogas, así como la percepción diferencial del empleo del Castigo-Coerción y de la Reprobación en adolescentes consumidores que presentan niveles de mayor permisividad actitudinal.

  13. Las nuevas plataformas televisivas en España y su influencia en el mercado

    Directory of Open Access Journals (Sweden)

    JV García Santamaría

    2014-06-01

    Full Text Available Introducción. Los procesos de absorción de las cadenas Cuatro y La Sexta por Telecinco y Antena 3, respectivamente, han configurado un nuevo mapa audiovisual en España. Las dos nuevas plataformas mediáticas, denominadas ahora Mediaset España y Atresmedia, han acumulado un considerable poder en la facturación televisiva, la configuración de las audiencias y la gestión publicitaria de la televisión en abierto. El objetivo es analizar las causas de estas integraciones, su influencia en el mercado televisivo español, y comprobar si afectan —en cuanto a “mercados relevantes”—, a la supervivencia de otros concurrentes. Metodología. Parte de la Economía Política de la Comunicación, que proporciona un marco teórico integrado, que se centra especialmente en la propiedad y la concentración de los medios de comunicación. Resultados y conclusiones. La conclusión general es que, desde el año 2010, fecha de la primera operación, el mercado audiovisual ha visto modificadas sus condiciones de competencia.

  14. Radiation and radiation protection; Strahlung und Strahlenschutz

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomaeus, Melanie (comp.)

    2017-04-15

    The publication of the Bundesamt fuer Strahlenschutz covers the following issues: (i) Human beings in natural and artificial radiation fields; (ii) ionizing radiation: radioactivity and radiation, radiation exposure and doses; measurement of ionizing radiation, natural radiation sources, artificial radiation sources, ionizing radiation effects on human beings, applied radiation protection, radiation exposure of the German population, radiation doses in comparison; (iii) non-ionizing radiation; low-frequency electric and magnetic fields, high-frequency electromagnetic fields, optical radiation; (iiii) glossary, (iv) units and conversion.

  15. Targeted alpha therapy using short-lived alpha-particles and the promise of nanobodies as targeting vehicle

    Science.gov (United States)

    Dekempeneer, Yana; Keyaerts, Marleen; Krasniqi, Ahmet; Puttemans, Janik; Muyldermans, Serge; Lahoutte, Tony; D’huyvetter, Matthias; Devoogdt, Nick

    2016-01-01

    ABSTRACT Introduction: The combination of a targeted biomolecule that specifically defines the target and a radionuclide that delivers a cytotoxic payload offers a specific way to destroy cancer cells. Targeted radionuclide therapy (TRNT) aims to deliver cytotoxic radiation to cancer cells and causes minimal toxicity to surrounding healthy tissues. Recent advances using α-particle radiation emphasizes their potential to generate radiation in a highly localized and toxic manner because of their high level of ionization and short range in tissue. Areas covered: We review the importance of targeted alpha therapy (TAT) and focus on nanobodies as potential beneficial vehicles. In recent years, nanobodies have been evaluated intensively as unique antigen-specific vehicles for molecular imaging and TRNT. Expert opinion: We expect that the efficient targeting capacity and fast clearance of nanobodies offer a high potential for TAT. More particularly, we argue that the nanobodies’ pharmacokinetic properties match perfectly with the interesting decay properties of the short-lived α-particle emitting radionuclides Astatine-211 and Bismuth-213 and offer an interesting treatment option particularly for micrometastatic cancer and residual disease. PMID:27145158

  16. Precision measurements on trapped antihydrogen in the ALPHA experiment.

    Science.gov (United States)

    Eriksson, S

    2018-03-28

    Both the 1S-2S transition and the ground state hyperfine spectrum have been observed in trapped antihydrogen. The former constitutes the first observation of resonant interaction of light with an anti-atom, and the latter is the first detailed measurement of a spectral feature in antihydrogen. Owing to the narrow intrinsic linewidth of the 1S-2S transition and use of two-photon laser excitation, the transition energy can be precisely determined in both hydrogen and antihydrogen, allowing a direct comparison as a test of fundamental symmetry. The result is consistent with CPT invariance at a relative precision of around 2×10 -10 This constitutes the most precise measurement of a property of antihydrogen. The hyperfine spectrum of antihydrogen is determined to a relative uncertainty of 4×10 -4 The excited state and the hyperfine spectroscopy techniques currently both show sensitivity at the few 100 kHz level on the absolute scale. Here, the most recent work of the ALPHA collaboration on precision spectroscopy of antihydrogen is presented together with an outlook on improving the precision of measurements involving lasers and microwave radiation. Prospects of measuring the Lamb shift and determining the antiproton charge radius in trapped antihydrogen in the ALPHA apparatus are presented. Future perspectives of precision measurements of trapped antihydrogen in the ALPHA apparatus when the ELENA facility becomes available to experiments at CERN are discussed.This article is part of the Theo Murphy meeting issue 'Antiproton physics in the ELENA era'. © 2018 The Author(s).

  17. Model for assessing alpha doses for a Reference Japanese Man

    International Nuclear Information System (INIS)

    Kawamura, Hisao

    1993-01-01

    In view of the development of the nuclear fuel cycle in this country, it is urgently important to establish dose assessment models and related human and environmental parameters for long-lived radionuclides. In the current program, intake and body content of actinides (Pu, Th, U) and related alpha-emitting nuclides (Ra and daughters) have been studied as well as physiological aspects of Reference Japanese Man as the basic model of man for dosimetry. The ultimate object is to examine applicability of the existing models particularly recommended by the ICRP for workers to members of the public. The result of an interlaboratory intercomparison of 239 Pu + 240 Pu determination including our result was published. Alpha-spectrometric determinations of 226 Ra in bone yielded repesentative bone concentration level in Tokyo and Ra-Ca O.R. (bone-diet) which appear consistent with the literature value for Sapporo and Kyoto by Ohno using a Rn emanation method. Specific effective energies for alpha radiation from 226 Ra and daughters were calculated using the ICRP dosimetric model for bone incorporating masses of source and target organs of Reference Japanese Man. Reference Japanese data including the adult, adolescent, child and infant of both sexes was extensively and intensively studied by Tanaka as part of the activities of the ICRP Task Group on Reference Man Revision. Normal data for the physical measurements, mass and dimension of internal organs and body surfaces and some of the body composition were analysed viewing the nutritional data in the Japanese population. Some of the above works are to be continued. (author)

  18. Liquid scintillation alpha particle spectrometry. Progress report

    International Nuclear Information System (INIS)

    Bell, L.L.; Hakooz, S.A.; Johnson, L.O.; Nieschmidt, E.B.; Meikrantz, D.H.

    1979-12-01

    Objective to develop a technique whereby Pu may be put into solution, extracted by solvent extraction into a suitable extractive scintillant and subsequently counted. Presented here are results of attempts to separate beta and alpha activities through pulse shape discrimination. A qualitative discussion is given which yields alpha particle peak widths, resolution and response. The detection efficiency for alpha particles in a liquid scintillant is 100%. Present detection sensitivities of the equipment being used are: 4.5 x 10 -6 μCi (100 s), 1.2 x 10 -6 μCi (1000 s), and 4.0 x 10 -7 μCi (10,000 s) at the 3 sigma level. The detectability of a particular alpha-emitting species is strongly dependent upon the population of other species. The ability to discriminate depends upon the system resolution. 14 figures, 2 tables

  19. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    Energy Technology Data Exchange (ETDEWEB)

    FISHER,R.K

    2004-04-01

    Three new approaches to obtain information on the confined fast alphas in International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by {approx}140 microns per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER.

  20. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    International Nuclear Information System (INIS)

    FISHER, R.K.

    2004-01-01

    Three new approaches to obtain information on the confined fast alphas in International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by ∼140 microns per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER

  1. Strichartz estimates on $alpha$-modulation spaces

    Directory of Open Access Journals (Sweden)

    Weichao Guo

    2013-05-01

    Full Text Available In this article, we consider some dispersive equations, including Schrodinger equations, nonelliptic Schrodinger equations, and wave equations. We develop some Strichartz estimates in the frame of alpha-modulation spaces.

  2. Targeted alpha therapy: Applications and current status

    Energy Technology Data Exchange (ETDEWEB)

    Bruchertseifer, Frank, E-mail: frank.bruchertseifer@ec.europa.eu [European Commission, Joint Research Centre, Karlsruhe (Germany)

    2017-07-01

    Full text: The field of targeted alpha therapy has been developed rapidly in the last decade. Besides {sup 223}Ra, {sup 211}At and {sup 212}Pb/{sup 212}Bi the alpha emitters {sup 225}Ac and {sup 213}Bi are promising therapeutic radionuclides for application in targeted alpha therapy of cancer and infectious diseases. The presentation will give a short overview about the current clinical treatments with alpha emitting radionuclides and will place an emphasis on the most promising clinical testing of peptides and antibodies labelled with {sup 225}Ac and {sup 213}Bi for treatment of metastatic castration-resistant prostate cancer patients with glioma and glioblastoma multiform, PSMA-positive tumor phenotype and bladder carcinoma in situ. (author)

  3. Calibration of alpha surface contamination monitor

    International Nuclear Information System (INIS)

    Freitas, I.S.M. de; Goncalez, O.L.

    1990-01-01

    In this work, the results, as well as the methodology, of the calibration of an alpha surface contamination monitor are presented. The calibration factors are obtained by least-squares fitting with effective variance. (author)

  4. Solar Imagery - Chromosphere - H-Alpha

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of H-alpha photographic datasets contributed by a number of national and private solar observatories located worldwide. Solar...

  5. Concepts of radiation protection

    International Nuclear Information System (INIS)

    2013-01-01

    This seventh chapter presents the concepts and principles of safety and radiation protection, emergency situations; NORM and TENORM; radiation protection care; radiation protection plan; activities of the radiation protection service; practical rules of radiation protection and the radiation symbol

  6. Energy dependence of event shapes and of $\\alpha_s$ at LEP 2

    CERN Document Server

    Abreu, P; Adye, T; Adzic, P; Albrecht, Z; Alderweireld, T; Alekseev, G D; Alemany, R; Allmendinger, T; Allport, P P; Almehed, S; Amaldi, Ugo; Amapane, N; Amato, S; Anassontzis, E G; Andersson, P; Andreazza, A; Andringa, S; Antilogus, P; Apel, W D; Arnoud, Y; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barbiellini, Guido; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Behrmann, A; Beillière, P; Belokopytov, Yu A; Belous, K S; Benekos, N C; Benvenuti, Alberto C; Bérat, C; Berggren, M; Bertini, D; Bertrand, D; Besançon, M; Bianchi, F; Bigi, M; Bilenky, S M; Bizouard, M A; Bloch, D; Blom, H M; Bonesini, M; Bonivento, W; Boonekamp, M; Booth, P S L; Borgland, A W; Borisov, G; Bosio, C; Botner, O; Boudinov, E; Bouquet, B; Bourdarios, C; Bowcock, T J V; Boyko, I; Bozovic, I; Bozzo, M; Branchini, P; Brenke, T; Brenner, R A; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Burgsmüller, T; Buschbeck, Brigitte; Buschmann, P; Cabrera, S; Caccia, M; Calvi, M; Camporesi, T; Canale, V; Carena, F; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Chabaud, V; Chapkin, M M; Charpentier, P; Chaussard, L; Checchia, P; Chelkov, G A; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Chudoba, J; Cieslik, K; Collins, P; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Cowell, J H; Crawley, H B; Crennell, D J; Crépé, S; Crosetti, G; Cuevas-Maestro, J; Czellar, S; Davenport, Martyn; Da Silva, W; Deghorain, A; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; de Boer, Wim; De Clercq, C; De Lotto, B; De Min, A; De Paula, L S; Dijkstra, H; Di Ciaccio, Lucia; Dolbeau, J; Doroba, K; Dracos, M; Drees, J; Dris, M; Duperrin, A; Durand, J D; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Ellert, M; Elsing, M; Engel, J P; Erzen, B; Espirito-Santo, M C; Falk, E; Fanourakis, G K; Fassouliotis, D; Fayot, J; Feindt, Michael; Fenyuk, A; Ferrari, P; Ferrer, A; Ferrer-Ribas, E; Ferro, F; Fichet, S; Firestone, A; Flagmeyer, U; Föth, H; Fokitis, E; Fontanelli, F; Franek, B J; Frodesen, A G; Frühwirth, R; Fulda-Quenzer, F; Fuster, J A; Galloni, A; Gamba, D; Gamblin, S; Gandelman, M; García, C; Gaspar, C; Gaspar, M; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Ghodbane, N; Gil, I; Glege, F; Gokieli, R; Golob, B; Gómez-Ceballos, G; Gonçalves, P; González-Caballero, I; Gopal, Gian P; Gorn, L; Górski, M; Guz, Yu; Gracco, Valerio; Grahl, J; Graziani, E; Green, C; Grimm, H J; Gris, P; Grosdidier, G; Grzelak, K; Günther, M; Guy, J; Hahn, F; Hahn, S; Haider, S; Hallgren, A; Hamacher, K; Hansen, J; Harris, F J; Hedberg, V; Heising, S; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Heuser, J M; Higón, E; Holmgren, S O; Holt, P J; Hoorelbeke, S; Houlden, M A; Hrubec, Josef; Huet, K; Hughes, G J; Hultqvist, K; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, C; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, P E; Joram, C; Juillot, P; Kapusta, F; Karafasoulis, K; Katsanevas, S; Katsoufis, E C; Keränen, R; Kersevan, Borut P; Khomenko, B A; Khovanskii, N N; Kiiskinen, A P; King, B J; Kinvig, A; Kjaer, N J; Klapp, O; Klein, H; Kluit, P M; Kokkinias, P; Koratzinos, M; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Krammer, Manfred; Kriznic, E; Krstic, J; Krumshtein, Z; Kubinec, P; Kurowska, J; Kurvinen, K L; Lamsa, J; Lane, D W; Langefeld, P; Lapin, V; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Leinonen, L; Leisos, A; Leitner, R; Lemonne, J; Lenzen, Georg; Lepeltier, V; Lesiak, T; Lethuillier, M; Libby, J; Liko, D; Lipniacka, A; Lippi, I; Lörstad, B; Loken, J G; Lopes, J H; López, J M; López-Fernandez, R; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Mahon, J R; Maio, A; Malek, A; Malmgren, T G M; Maltezos, S; Malychev, V; Mandl, F; Marco, J; Marco, R P; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Masik, J; Mazzucato, F; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; McPherson, G; Meroni, C; Meyer, W T; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Moch, M; Møller, R; Mönig, K; Monge, M R; Moreau, X; Morettini, P; Morton, G A; Müller, U; Münich, K; Mulders, M; Mulet-Marquis, C; Muresan, R; Murray, W J; Muryn, B; Myatt, Gerald; Myklebust, T; Naraghi, F; Nassiakou, M; Navarria, Francesco Luigi; Navas, S; Nawrocki, K; Negri, P; Némécek, S; Neufeld, N; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nikolenko, M; Nomokonov, V P; Normand, Ainsley; Nygren, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Orazi, G; Österberg, K; Ouraou, A; Paganoni, M; Paiano, S; Pain, R; Paiva, R; Palacios, J; Palka, H; Papadopoulou, T D; Papageorgiou, K; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Pegoraro, M; Peralta, L; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Phillips, H T; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Ratoff, P N; Read, A L; Rebecchi, P; Redaelli, N G; Regler, Meinhard; Reid, D; Reinhardt, R; Renton, P B; Resvanis, L K; Richard, F; Rídky, J; Rinaudo, G; Røhne, O M; Romero, A; Ronchese, P; Rosenberg, E I; Rosinsky, P; Roudeau, Patrick; Rovelli, T; Royon, C; Ruhlmann-Kleider, V; Ruiz, A; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sampsonidis, D; Sannino, M; Schneider, H; Schwemling, P; Schwering, B; Schwickerath, U; Schyns, M A E; Scuri, F; Seager, P; Sedykh, Yu; Segar, A M; Sekulin, R L; Shellard, R C; Sheridan, A; Siebel, M; Simard, L C; Simonetto, F; Sissakian, A N; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Sopczak, André; Sosnowski, R; Spassoff, Tz; Spiriti, E; Sponholz, P; Squarcia, S; Stanescu, C; Stanic, S; Stevenson, K; Stocchi, A; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Tegenfeldt, F; Terranova, F; Thomas, J; Timmermans, J; Tinti, N; Tkatchev, L G; Todorova-Nová, S; Tomaradze, A G; Tomé, B; Tonazzo, A; Tortora, L; Tranströmer, G; Treille, D; Tristram, G; Trochimczuk, M; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tzamarias, S; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; Van der Velde, C; van Apeldoorn, G W; van Dam, P; Van Doninck, W K; Van Eldik, J; Van Lysebetten, A; Van Vulpen, I B; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Verzi, V; Vilanova, D; Vitale, L; Vlasov, E; Vodopyanov, A S; Vollmer, C F; Voulgaris, G; Vrba, V; Wahlen, H; Walck, C; Weiser, C; Wicke, D; Wickens, J H; Wilkinson, G R; Winter, M; Witek, M; Wolf, G; Yi, J; Yushchenko, O P; Zaitsev, A; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zucchelli, G C; Zumerle, G

    1999-01-01

    Infrared and collinear safe event shape distributions and their mean values are determined using the data taken at ve di erent centre of mass energies above $M_Z$ with the DELPHI detector at LEP. From the event shapes, the strong coupling $\\alpha_s$ is extracted in $O(\\alpha^2_s)$, NLLA and a combined scheme using hadronisation corrections evaluated with fragmentation model generators as well as using an analytical power ansatz. Comparing these measurements to those obtained at MZ, the energy dependence (running) of $\\alpha_s$ is accessible. The logarithmic energy slope of the inverse strong coupling is measured to be $d\\alpha_{s}^{-1}/d log(E_{cm}) = 1.39 \\pm 0.34(stat) \\pm 0.17(syst)$, in good agreement with the QCD expectation of 1.27.

  7. Influence of fast alpha diffusion and thermal alpha buildup on tokamak reactor performance

    International Nuclear Information System (INIS)

    Uckan, N.A.; Tolliver, J.S.; Houlberg, W.A.; Attenberger, S.E.

    1988-01-01

    The effect of fast alpha diffusion and thermal alpha accumulation on the confinement capability of a candidate Engineering Test Reactor plasma (Tokamak Ignition/Burn Experimental Reactor) in achieving ignition and steady-state driven operation has been assessed using both global and 1-1/2-dimensional transport models. Estimates are made of the threshold for radial diffusion of fast alphas and thermal alpha buildup. It is shown that a relatively low level of radial transport, when combined with large gradients in the fast alpha density, leads to a significant radial flow with a deleterious effect on plasma performance. Similarly, modest levels of thermal alpha concentration significantly influence the ignition and steady-state burn capability

  8. Radiation myelopathy

    International Nuclear Information System (INIS)

    Berlit, P.

    1987-01-01

    After a review of the world literature, the case histories of 43 patients with radiation myelopathy are analyzed. In 1 patient there was a radiation injury of the medulla oblongata, in 2, cervical, in 28, thoracic, and in 12, lumbosacral. In the medulla oblongata lesion an alternans syndrome resulted. The patients with cervical and thoracic radiation myelopathies presented with a Brown-Sequard syndrome, a spinalis anterior syndrome or a transversal syndrome with pyramidal and spinothalamic tract involvement as the most prominent signs. For this group the term 'pyramidal-spinothalamic radiation myelopathy' is proposed. In lumbosacral radiation lesions a pure anterior horn syndrome may lead to spinothalamic tract involvement and the development of a cauda conus syndrome. The clinical presentation of these cases suggests that the location of the radiation lesion is most likely the region of the conus medullaris. The most frequent initial symptom was dysesthesia; the patients complained of burning pain or a feeling of coldness. Usually the neurological deficits were progressive, in pyramidal-spinothalamic radiation myelopathy over 12 months in average, in lumbosacral radiation lesions up to 10 years. The latent period between the finish of radiation therapy and the first neurological signs was 8 months (median) in cervical and thoracic myelopathy and 33 months in lumbosacral lesions. For the entire group of 43 patients there was an inverse relationship between the radiation dose (ret) and the latent period. A positive relation could be demonstrated between the age of patients at the time of radiation therapy and the latent period. Patients simultaneously receiving cytostatic drugs presented after a longer latent period than the remaining group. (orig./MG)

  9. Lyman alpha emission in nearby star-forming galaxies with the lowest metallicities and the highest [OIII]/[OII] ratios

    Science.gov (United States)

    Izotov, Yuri

    2017-08-01

    The Lyman alpha line of hydrogen is the strongest emission line in galaxies and the tool of predilection for identifying and studying star-forming galaxies over a wide range of redshifts, especially in the early universe. However, it has become clear over the years that not all of the Lyman alpha radiation escapes, due to its resonant scattering on the interstellar and intergalactic medium, and absorption by dust. Although our knowledge of the high-z universe depends crucially on that line, we still do not have a complete understanding of the mechanisms behind the production, radiative transfer and escape of Lyman alpha in galaxies. We wish here to investigate these mechanisms by studying the properties of the ISM in a unique sample of 8 extreme star-forming galaxies (SFGs) that have the highest excitation in the SDSS spectral data base. These dwarf SFGs have considerably lower stellar masses and metallicities, and higher equivalent widths and [OIII]5007/[OII]3727 ratios compared to all nearby SFGs with Lyman alpha emission studied so far with COS. They are, however, very similar to the dwarf Lyman alpha emitters at redshifts 3-6, which are thought to be the main sources of reionization in the early Universe. By combining the HST/COS UV data with data in the optical range, and using photoionization and radiative transfer codes, we will be able to study the properties of the Lyman alpha in these unique objects, derive column densities of the neutral hydrogen N(HI) and compare them with N(HI) obtained from the HeI emission-line ratios in the optical spectra. We will derive Lyman alpha escape fractions and indirectly Lyman continuum escape fractions.

  10. An automated alpha scanner for estimating plutonium contamination levels on FBTR fuel pin

    International Nuclear Information System (INIS)

    Bagul, D.G.; Sharma, V.P.; Benadikar, S.V.; Karnani, N.K.; Kamath, K.V.

    1995-01-01

    An automated alpha scanner has been developed for estimating plutonium contamination on SS clad fuel pins fabricated in Radiometallurgy Division for Fast Breeder Test Reactor (FBTR). The unit can detect as low as 1% of the allowed contamination limit for the fuel pin. Because of automation, large number of pins can be systematically scanned for Pu contamination with minimum radiation exposure to the operator. (author). 3 refs., 1 fig., 1 tab

  11. Flexible silicon-based alpha-particle detector

    Science.gov (United States)

    Schuster, C. S.; Smith, B. R.; Sanderson, B. J.; Mullins, J. T.; Atkins, J.; Joshi, P.; McNamara, L.; Krauss, T. F.; Jenkins, D. G.

    2017-08-01

    The detection of alpha particles in the field can be challenging due to their short range in air of often only a few centimeters or less. This short range is a particular issue for measuring radiation inside contaminated pipework in the nuclear industry, for which there is currently no simple method available without cutting the pipes open. Here, we propose an approach for low cost, rapid, and safe identification of internally contaminated pipework based on a flexible 30 × 10 mm2 sheet of 50 μm thin crystalline silicon. Following established fabrication steps of pn-junction diodes, we have constructed a device with a signal-to-noise ratio of >20 in response to 5.5 MeV alpha-particles using a bespoke amplifier circuit. As flexible detectors may readily conform to a curved surface and are able to adapt to the curvature of a given pipeline, our prototype device stands out as a viable solution for nuclear decommissioning and related applications.

  12. Controlling the alpha risk in the EDF facilities

    International Nuclear Information System (INIS)

    Roupioz, A.; Labouglie, J.F.

    2003-01-01

    Due to the characteristics of the radiation they emit. alpha emitters are highly radio-toxic in terms of internal exposure but their low penetration makes them inoffensive in terms of external exposure. In PWR power plants, α emitters are rare and the risk of contamination is particularly low. Until now, this risk has always been well controlled by the operator, and is not one of the main Radiological protection priorities within EDF. Nevertheless, requirements are always increasing, whether for the radiological protection of workers or the public, and have led EDF to reconsider the α risk, to ensure that the current provisions are adequate and to reinforce them if necessary. Therefore, a study of the α risk was started in 1999. (authors)

  13. An Alpha spectrometer for measuring radon daughter individual activity concentration

    International Nuclear Information System (INIS)

    Berico, M.; Formignani, M.; Mariotti, F.

    2001-01-01

    In the frame of the program of the Institute for Radiation Protection of ENEA, related to the evaluation of dose from radon and thoron progeny, an alpha spectrometer for the continuous air monitoring (CAM type) of radon and thoron has been realized. The constructive characteristics of the device are here presented together with energy and efficiency calibration. The device allows, by means of a screen type diffusion battery and a filter, to determinate the single radioactivity of each radionuclide of the progeny selecting them in relation to their diffusive behaviour (dichotomous particle size selection). The three-count filter method has been employed to measure the concentrations of 218 Po, 214 Pb and 214 Bi in air. Radon and thoron effective doses using a dosimetric, instead of an epidemiologic approach, will be then evaluated [it

  14. The Alpha Magnetic Spectrometer on the International Space Station

    CERN Document Server

    Paniccia, M

    2008-01-01

    The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to measure charged cosmic rays spectra up to TV region, with high energy photon detection capability up to few hundred GeV. With the large acceptance, the long duration (3 years) and the state of the art particle identification techniques, AMS will provide the most sensitive search for the existence of antimatter nuclei and for the origin of dark matter. The detector is being constructed with an eight layers Silicon Tracker inside a large superconducting magnet, providing a ~ 0.8 Tm2 bending power and an acceptance of ~ 0.5 m2sr. A Transition Radiation Detector and a 3D Electromagnetic Calorimeter allow for electron, positron and photon identification, while independent velocity measurements are performed by a Time of Flight scintillating system and a Ring Image Cherenkov detector. The overall construction is due to be completed by 2008.

  15. Pulsar H(alpha) Bowshocks probe Neutron Star Physics

    Science.gov (United States)

    Romani, Roger W.

    2014-08-01

    We propose a KOALA/AAOmega study of southern pulsar bow shocks. These rare, Balmer-dominated, non-radiative shocks provide an ideal laboratory to study the interaction of the relativistic pulsar wind with the ISM. We will cover H(alpha) at high spectral resolution to measure the kinematics of the upstream ISM and the post-shock flow, while the blue channel measures the Balmer decrement and probes for a faint cooling component. These data, with MHD models, allow us to extract the 3D flow geometry and the orientation and asymmetry of the pulsar wind. These data can also measure the pulsar spindown power, thus estimating the neutron star moment of inertia and effecting a fundamental test of dense matter physics.

  16. The family of alpha coefficients in X-ray fluorescence analysis

    International Nuclear Information System (INIS)

    Lachance, G.R.

    1979-01-01

    The demand for comprehensive analysis of materials by XRF using automated instrumentation has led to increasing use of the coefficient approach for dealing with the ever-present interelement effect. A survey of the literature shows that this has often led to a multiplicity of families of calibration curves being replaced by a multiplicity of tables of correction coefficients. A practical approach is outlined which facilitates the recognition of (a) the alpha subset of influence coefficients, and (b) three related subsets of alpha coefficients - basic, modified and hybrid. This mobility of alpha coefficients (alloys, oxides, fusions, solutions) coupled to their adaptability (geometry, primary radiation) and accessibility (theoretical, experimental) has wide implications. It permits a consolidated view of the influence of coefficients, and comparison of the sign, magnitude and pattern of basic alphas so as to establish if and when there is consensus. the confirmed alpha coefficients thus obtained can then be transferred with confidence to suit specific operating conditions and methods. Examples are given using data that have appeared in XRF literature. (author)

  17. Gene conversion of two functional goat alpha-globin genes preserves only minimal flanking sequences.

    Science.gov (United States)

    Schon, E A; Wernke, S M; Lingrel, J B

    1982-06-25

    We have determined the complete nucleotide sequence of the nonallelic adult goat I alpha- and II alpha-globin genes and, as is the case with the duplicated human alpha-to each other. Such high homology (99%) has most likely been preserved via a gene conversion mechanism. The conversion unit in goats is only about 9000 base pairs in length, and contained within this short region are all the known signals required for accurate and efficient transcription, with the CCAAT box adjacent to the 5'-boundary of the conversion unit and the poly(A) addition site adjacent to the 3' end. This conversion unit is also flanked by a 23-base-pair direct repeat "boundary sequence," vestiges of which are also observable in the human and mouse alpha-globin genes and pseudogenes. These direct repeats imply that a transposition-like event may have been responsible for the insertion of an ancestral alpha-like sequence into a new chromosomal locus, and that this insertion event and subsequent gene duplication may have predated the mammalian radiation.

  18. Change in the alpha criterion policy: variable based on the maximum individual dose function

    International Nuclear Information System (INIS)

    Freitas Acosta Perez, C. de; Sordi, G.M.A.A.

    2006-01-01

    The Alpha value is an extremely important criterion because it determines the time that a country takes to achieve its proposals in order to decrease the workers doses involved with ionizing radiation sources. Currently the countries adopt a single value for alpha based on the annual gross national product, GNP, per capita. The aim of this paper is to show that the selection of a curve for the alpha in place of a single value would be more efficient. This curve would provide alpha values that would will be constraints to the biggest individual doses presented in each optimization process as applied both to designs and to operations. These maximum individual doses would represent the dose distribution among the workers team. To build the curve, the alpha values suggested are not based on the GNP per capita but on a distribution function of the maximum individual doses and on the time necessary to reach the proposal of 1/10 of the annual dose limit foreseen in the sequential optimization processes, that is to reach the region where the individual doses are considered acceptable. So, the differential equations will be - d X/dS =α(H m ax). To clarify our sight about the alpha value we started using the uranium mine example presented in ICRP publication 55, adopting the decision-aiding technique known as extended cost-benefit. for right. Then we used the same example in a hypothetical curve with portions: constant, linear, quadratic and exponential. Eventually we discussed briefly the different shapes of the curves that the alpha value can assume in function of the individual doses. Each of these shapes can correspond to the so called 'risk neutral attitude', 'risk adverse attitude' or 'risk prone attitude' suggested in the appendix B of the ICRP publication 55

  19. Measurement of the angle alpha at BABAR

    Energy Technology Data Exchange (ETDEWEB)

    Perez, A.; /Orsay, LAL

    2009-06-25

    The authors present recent measurements of the CKM angle {alpha} using data collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory, operating at the {Upsilon}(4S) resonance. They present constraints on {alpha} from B {yields} {pi}{pi}, B {yields} {rho}{rho} and B {yields} {rho}{pi} decays.

  20. Improved peak shape fitting in alpha spectra

    OpenAIRE

    POMME Stefaan; CARO MARROYO BELEN

    2014-01-01

    Peak overlap is a recurrent issue ina lpha-particle spectrometry, not only in routine analyses but also in the high-resolution spectra from which reference values for alpha emission probabilities are derived. In this work, improved peak shape formulae are presented for the deconvolution of alpha-particle spectra. They have been implemented as fit functions in a spreadsheet application and optimum fit parameters were searched with built-in optimisation routines. Deconvolution results are shown...