TRACK STRUCTURE CALCULATIONS

Información del proyecto

Identificador del acuerdo de subvención: BI6*0011

Proyecto cerrado

Fecha de inicio 1 Enero 1985

Fecha de finalización 31 Diciembre 1989

Financiado con arreglo a

• Multiannual research and training programme (Euratom) in the field of radiation protection, 1985-1989

Coste total

Sin datos

Aportación de la UE

Sin datos

Coordinado por

GSF - FORSCHUNGSZENTRUM FUER UMWELT UND GESUNDHEIT GMBH
Germany

Objetivo

IT IS WELL-KNOWN THAT DETAILED INFORMATION ON THE RELEVANT ASPECTS OF THE PRIMARY STRUCTURES OF MOLECULAR CHANGES PRODUCED IN MATTER BY IRRADIATION WITH IONIZING RADIATION REPRESENTS AN INDISPENSIBLE PREREQUISITE FOR ANY UNDERSTANDING AND INTERPRETATION OF RADIATION EFFECTS IN PARTICULAR IN THE IMPORTANT LOW DOSE REGION. THIS FACT HAS BEEN LEADING E.G. TO INCREASING RESEARCH EFFORTS IN MICRODOSIMETRY AND TRACK STRUCTURE THEORY. HOWEVER, ALL THESE EFFORTS COULD NOT YET REACH THEIR FINAL GOAL RELEVANT TO RADIATION PROTECTION, NAMELY THE DESCRIPTION OF THE PHYSICAL TRACK STRUCTURES IN REALISTIC BIOLOGICAL TARGETS AND THE IDENTIFICATION OF ITS IMPORTANT CHARACTERISTICS DETERMINING THE TYPES AND FREQUENCIES OF SUBSEQUENT BIOLOGICAL REACTIONS AND THEIR CONSEQUENCES. THIS SHORTCOMING HAS BEEN MAINLY DUE TO THE LACK OF BASIC EXPERIMENTAL TECHNIQUES, DATA AND THEORIES IN THE PAST, AND THEREFORE MAINLY GASEOUS, HOMOGENEOUS MODEL SUBSTANCES HAVE BEEN CONSIDERED AND USED IN MEASUREMENTS.
RECENTLY NEW EXPERIMENTAL DATA ON PROCESSES IN CONDENSED TARGETS (ALSO IN BIOLOGICAL MOLECULES LIKE DNA) ARE BECOMING AVAILABLE FROM OTHER FIELDS OF RESEARCH, AND LARGER AND FASTER COMPUTERS RENDER POSSIBLE NEW TYPES OF SIMULATION AND ANALYSIS PROGRAMMES. THEREFORE, IT NOW APPEARS POSSIBLE TO:
- IDENTIFY THE IMPORTANT ENERGY TRANSFER AND ABSORPTION PROCESSES IN CONDENSED BIOLOGICAL MOLECULES,
- DERIVE CROSS SECTIONS FOR THESE PROCESSES,
- DESIGN COMPUTER PROGRAMMES TO SIMULATE CHARGED PARTICLE TRACKS IN HETEROGENEOUS AND STRUCTURED COMPLEX TARGETS, AS E.G. A MAMMALIAN CELL, USING THE PHYSICAL INPUT DATA MENTIONED ABOVE, AND TO
- APPLY SOPHISTICATED CLASSIFICATION TECHNIQUES TO IDENTIFY THOSE PROPERTIES OF SUCH TRACK STRUCTURES WHICH ARE RELEVANT FOR THE INTERPRETATION OF BIOLOGICAL RADIATION EFFECTS AT LOW DOSES.
THESE FOUR POINTS ARE THE TOPICS OF THIS RESEARCH WORK PROPOSED.
Objective of the reporting period: to finalize work on and describe all interaction cross-sections needed in this project, taking shortcomings into account which cannot be resolved presently (due to the lack of adequate experiments and theories); to extend the HZE-cross-sections to the parameter range used in radiobiological experiments at GSI and Bevelac for the interpretation of the experimental data obtained there; to use the alpha-particle and electron code to estimate the potential hazard from incorporated warm and hot particles emitted from the Chernobyl reactor.
FIRST, CROSS SECTIONS FOR THE PROCESSES CONSIDERED IMPORTANT FOR ENERGY TRANSFER, TRANSPORT AND ABSORPTION IN DNA AND OTHER MOLECULES IN A REALISTIC BIOLOGICAL CELL WILL BE DERIVED FOR THE FOLLOWING PRIMARY RADIATIONS:
- ALPHA PARTICLES (IN PARTICULAR FROM NATURAL ISOTOPES LIKE RADON AND DAUGHTER PRODUCTS, BUT ALSO FOR TRANSURANIUM ELEMENTS, E.G. PU,AM,NP);
- ELECTRONS (E.G. PHOTOEFFECT AND COMPTON ELECTRONS FROM PHOTON FIELDS AND FROM RADIOISOTOPES (E.G. TC 99, IODINE) USED IN MEDICINE);
- HIGH CHARGE AND ENERGY PARTICLES (WHICH ARE OF RELEVANCY FOR RADIATION PROTECTION OF ASTRONAUTS).
THEN THE EXISTING MONTE-CARLO PROGRAMMES FOR SIMULATION OF CHARGED PARTICLE TRACK STRUCTURES IN HOMOGENEOUS, UNIFORM TARGETS WILL BE MODIFIED AND EXTENDED TO BE ABLE TO CALCULATE TRACK STRUCTURES IN COMPLEX HETEROGENEOUS AND STRUCTURED TARGETS LIKE A BIOLOGICAL CELL.
FINALLY, NEW CLASSIFICATION AND CORRELATION ANALYSIS PROGRAMMES WILL BE APPLIED TO SIMULATED TRACK STRUCTURES WITH RESPECT TO THE IDENTIFICATION OF THOSE CHARACTERISTICS OF TRACK STRUCTURES WHICH APPEAR FROM THE PHYSICAL POINT OF VIEW MOST RELEVANT FOR THE DETERMINATION OF THE FOLLOWING BIOLOGICAL END POINTS:
- DNA-DAMAGES (SINGLE, DOUBLE STRAND BREAKS, BASE DAMAGES),
- CHROMOSOME ABERRATIONS (FORMATION OF VARIOUS STRUCTURAL CHANGES),
- CELL INACTIVATION,
- CELLULAR MUTATIONS AND
- CELLULAR TRANSFORMATIONS.
THIS LATTER WORK (AND - IF PROGRESS OF KNOWLEDGE PERMITS - AN ANALYSIS OF THE IMPLICATIONS FOR CARCINOGENESIS) WILL BE CARRIED OUT IN COOPERATION WITH SCIENTISTS WORKING IN THE SECTIONS "NON-STOCHASTIC EFFECTS OF IONIZING RADIATION", "GENETIC EFFECTS OF IONIZING RADIATION" AND "RADIATION CARCINOGENESIS" OF THE CEC-RADIATION PROTECTION PROGRAMME.

Ámbito científico (EuroSciVoc)

• ciencias naturales › ciencias químicas › química inorgánica › gases nobles
• ciencias naturales › ciencias biológicas › bioquímica › biomoléculas
• ciencias naturales › ciencias físicas › física nuclear
• ciencias naturales › ciencias químicas › química inorgánica › halógenos
• ciencias naturales › ciencias físicas › física teórica › física de partículas › fotones

Programa(s)

• FP1-RADPROT 6C - Multiannual research and training programme (Euratom) in the field of radiation protection, 1985-1989

Tema(s)

Datos no disponibles

Convocatoria de propuestas

Datos no disponibles

Régimen de financiación

CSC - Cost-sharing contracts

Coordinador

GSF - FORSCHUNGSZENTRUM FUER UMWELT UND GESUNDHEIT GMBH

• Aportación de la UE: Sin datos
• Dirección: Ingolstaedter Landstrasse 1 ; 85764 NEUHERBERG ; Alemania
• Coste total: Sin datos