Book reviewsDetermination of Dose Equivalents from External Radiation Sources, Part 2. ICRU Report 43, pp. x + 51, 1988 (International Commission on Radiation Units and Measurements, Maryland, USA), $17. ISBN 0–913394–33–5

1990 ◽  
Vol 63 (749) ◽  
pp. 409-409
Author(s):  
Anne Walker
2021 ◽  
Vol 11 (17) ◽  
pp. 7820
Author(s):  
Marco Martini ◽  
Anna Galli

In this work, we present some new results in applying thermoluminescence (TL) dating to the clay core of bronze statues. This is very important, due to the impossibility of directly dating a metal. Very few cases of indirect dating of clay cores by TL are reported in the literature. We re-considered three cases of dating of clay core from important bronzes in Rome. The parameters to be considered were not easy to calculate in the case of the Lupa Capitolina. However, its traditionally reported Etruscan origin is definitely ruled out, even if the accuracy in the dating is too low to precisely propose a date of the casting. The comparison with radiocarbon results shows good agreement for a Medieval dating. Two other bronze statues were analysed in order to date their casting by TL; a horse from Musei Capitolini resulted to have been cast in the Greek classical period, excluding its casting in the Rome imperial period. A third study shows that, in particularly favourable situations, TL dating of clay core can give rather precise results. This is the case where in the clay core are present materials that behave like good dosimeters, as generally happens in dating ceramics. Furthermore, the possibility of measuring all the parameters influencing the calculation of the dose rate is essential; both the external radiation sources and the radiation reduction by the water content must be taken into account. This was the case of Saint Peter in the Vatican that turned out to be a cast from the beginning of the XIV century.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marc Benjamin Hahn ◽  
Julián Mateo Zutta Villate

AbstractDose enhancement by gold nanoparticles (AuNP) increases the biological effectiveness of radiation damage in biomolecules and tissue. To apply them effectively during cancer therapy their influence on the locally delivered dose has to be determined. Hereby, the AuNP locations strongly influence the energy deposit in the nucleus, mitochondria, membrane and the cytosol of the targeted cells. To estimate these effects, particle scattering simulations are applied. In general, different approaches for modeling the AuNP and their distribution within the cell are possible. In this work, two newly developed continuous and discrete-geometric models for simulations of AuNP in cells are presented. These models are applicable to simulations of internal emitters and external radiation sources. Most of the current studies on AuNP focus on external beam therapy. In contrast, we apply the presented models in Monte-Carlo particle scattering simulations to characterize the energy deposit in cell organelles by radioactive 198AuNP. They emit beta and gamma rays and are therefore considered for applications with solid tumors. Differences in local dose enhancement between randomly distributed and nucleus targeted nanoparticles are compared. Hereby nucleus targeted nanoparticels showed a strong local dose enhancement in the radio sensitive nucleus. These results are the foundation for future experimental work which aims to obtain a mechanistic understanding of cell death induced by radioactive 198Au.


2006 ◽  
Vol 133 ◽  
pp. 1173-1175
Author(s):  
C. A. Back ◽  
J. F. Seely ◽  
J. L. Weaver ◽  
U. Feldman ◽  
R. Tommasini ◽  
...  
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