Abstract This paper aims to evaluate the dosimetric characteristics of modified VIPARnd for radiotherapy dosimetry using optical investigations. The absorbance spectrum of the irradiated gel dosimeter was evaluated optically with spectrophotometer techniques and with a CMOS imaging system. The useful dose range for the peak value and the relative area under the absorbance curve is 3-20 Gy. The dose-response curve for CMOS readout has an interval of linearity from 3-20 Gy. The modified VIPARnd developed has a good dose range and good temporal stability in the spectrophotometric analysis of the intervals studied. The CMOS readout is transportable, cheaper, easier to use and an excellent alternative for dosimetry.

Abstract Biodegradable polymers have become part of the realm of polymer science with specially when associated to renewable sources. Unraveling the plasticizer effect of natural occurring fatty acids in the Brazilian Cerrado on amylose oligomers was aimed in this work in an aqueous environment. Since the interactions within a material are of extreme importance to its molecular behavior, the main focus was directed to the molecular interactions whether intra or intermolecular type. Molecular Mechanics and Dynamics were carried out to shed light on this issue. The simulation results suggest the fatty acids could perform as efficient plasticizers for more complex polysaccharides such as starch. It also highlights the importance the solvation on the system stabilization, thus contributing to a clearer understanding of the chemical interactions role on plasticization. Our results provide a basis for simulating more complex systems such as a clay-mineral which will culminate in the parameterization for mesoscale studies.