Sökning: "γ rays"

Visar resultat 6 - 10 av 22 avhandlingar innehållade orden γ rays.

  1. 6. In vitro and in vivo aspects of intrinsic radiosensitivity

    Författare :Karl Brehwens; Andrzej Wojcik; Siamak Haghdoost; Wolfgang Dörr; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Radiation biology; changing dose rates; cytogenetics; hypothermia; X-rays; radiotherapy; osteoradionecrosis; biomarkers; oxidative stress; individual radiosensitivity; molekylär biovetenskap; Molecular Biosciences;

    Sammanfattning : This thesis focuses on how physical and biological factors influence the outcome of exposures to γ/X-rays. That the dose rate changes during real life exposure scenarios is well-known, but radiobiological data from exposures performed at increasing or decreasing dose rates is lacking. LÄS MER

  2. 7. Quantum-state Selective Nuclear Decay Spectroscopy

    Författare :Ch. Lorenz; Kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nuclear structure; alpha decay; beta decay; gamma rays; spectroscopy; Penning traps; shell-model calculations; Geant4 Monte Carlo Simulations;

    Sammanfattning : This thesis focusses on the results of two experiments employing Penning traps to prepare pure beams of the 213Ra ground state and 127Cd, which were then studied with the decay-spectroscopy setup TASISpec. The experiments were conducted with SHIPTRAP at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany, and JYFLTRAP at the IGISOL Accelerator Facility at the University of Jyväskylä, Finland. LÄS MER

  3. 8. Characterisation of the Neutron Wall and of Neutron Interactions in Germanium-Detector Systems

    Författare :Joa Ljungvall; Johan Nyberg; Andres Gadea; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; High-purity Ge detectors; Liquid scintillator detectors; Neutron scattering; Digital electronics; Time-of-flight technique; Pulse-shape simulation and analysis; Monte Carlo simulations; Geant4; Gamma-ray tracking; AGATA; Neutron Wall; Kärnfysik; Nuclear physics; Kärnfysik;

    Sammanfattning : A Monte Carlo simulation of the Neutron Wall detector system has been performed using Geant4, in order to define optimum conditions for the detection and identification of multiple neutrons. Emphasis was put on studying the scattering of neutrons between different detectors, which is the main source of the apparent increase of the number of detected neutrons. LÄS MER

  4. 9. Internal Bremsstrahlung Accompanying the Positon Decay of 82Rb

    Författare :Roland Akselsson; Börje Persson; Ergonomi och aerosolteknologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; internal Bremsstrahlung; positon decay;

    Sammanfattning : The internal bremsstrahlung from the positon decay of 82Rb has been measured in the energy ranges 0.95-1.3 and 1.7-2. LÄS MER

  5. 10. Studies of DNA repair strategies in response to complex DNA damages

    Författare :Ainars Bajinskis; Mats Harms-Ringdahl; Bo Stenerlöw; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ionizing radiation; complex DNA damage; indirect effect of radiation; dimethyl sulfoxide; molekylärgenetik; Molecular Genetics;

    Sammanfattning : The main aim of this thesis was to study the role of the indirect actions of γ-rays and α-particles on the complexity of primary DNA damages and the repair fidelity of major DNA repair pathways: non-homologous end joining (NHEJ), homologous recombination repair (HRR) and base excision repair (BER). The complexity of radiation-induced damages increases and the proximity between damages decreases with increasing LET due to formation of ionization clusters along the particle track. LÄS MER