A new simulation protocol for the prediction of the infrared absorption of the amide I vibration of proteins was developed. The method incorporates known effects on the intrinsic frequencies (backbone conformation, inter-peptide and peptide-solvent hydrogen bonding) and couplings (nearest neighbor coupling, transition dipole coupling) of amide I oscillators in a parametrized manner. Model parameters for the simulation of amide I spectra were determined through fitting and optimization of simulated spectra to experimentally measured infrared spectra of 44 proteins that represent maximum structural variation in terms of different folds and secondary structure contents. Prediction of protein spectra using the optimized parameters resulted in good agreement with experimental spectra and in a considerable improvement compared to a description involving only transition dipole coupling.

A characterization of the Galactic Cosmic Ray (GCR) induced radiation environment on-board Columbus and the International Space Station (ISS) has been carried out using the Geant4 Monte Carlo particle transport toolkit and detailed geometry models of Columbus and ISS. Dose and dose equivalent rates, as well as penetrating particle spectra are presented. Simulation results indicate that the major part of the dose rates due to GCR protons are associated with secondary particles produced in the hull of ISS. Neutrons contribute about 15% of the GCR proton dose equivalent rate and mesons about 10%. More than 40% of the simulated GCR proton dose and dose equivalent rates are due to protons in the energy range above 10 GeV. Protons in the energy range above 50 GeV contribute only 5% to the dose rates. The total simulated dose and dose equivalent rates at solar maximum are 63 Gy/d and 123 Sv/d, respectively. The dose equivalent rate underestimates measurements made during the 2001 solar maximum. The discrepancy can be attributed to deficiencies in hadronic ion-nuclei interaction models for heavy ions and to the lack of such models above 10 GeV/N in Geant4.

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The Dose Estimation by Simulation of the ISS Radiation Environment (DESIRE) project aims to accurately calculate radiation fluxes and doses to astronauts inside the European Columbus module of the International Space Station using Geant4. Since Geant4 has not been previously used for this type of application it needs to be validated. This will be followed by a detailed evaluation of the incident radiation fields on ISS and culminate with the geometry modeling and full-scale flux and dose simulations for Columbus. Geant4 validation studies and comparisons to other tools are presented. These concern the angle and energy distributions of particles leaving irradiated targets and of energy depositions in the targets. Comparisons are made between simulations using different Geant4 physics models, experimental data, and other particle transport programs. Geant4 using the "Binary Cascade" model for inelastic nucleon reactions performs very well in these comparisons, but some issues with other models remain to be resolved if they are to be used for space radiation shielding applications. Results of Geant4 simulations of the transport of some relevant radiation field components through the hull of a simplified model of Columbus are also presented.

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