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Sodium Iodide doped with Thallium NaI(Tl) scintillation detectors have potential for the development of an active dosimeter for photon radiation. We aim to show that the photon dosimetry response for NaI(Tl) scintillation detector may be optimized by employing the Particle Swarm optimization algorithm, when the selective data sampling is applied for the detector readout. In this work, Sodium Iodide doped with Thallium NaI(Tl) scintillation detector is considered due to being highly sensitive to gamma radiation, and one of the affordable room temperature detectors. In this research, we intend to measure the dosimetry response of the NaI(Tl) detector for various gamma sources, as an example, by measuring the ambient dose equivalent H*(10) for different gamma radioactive sources. Furthermore, we demonstrate that the photon dosimetry response may be well optimized for various energies, especially at lower energies, by increasing the energy interval number in data sampling over the NaI(Tl) scintillation detector readout with the help of an optimization algorithm. The simulation software Geant4 has been used for determining the NaI(Tl) scintillation detector readout. To this end, experimental ambient dose equivalent measurements for gamma radiation sources are compared with the theoretical results. As three and six energy intervals are considered for the selective data sampling along with an optimization algorithm based on NaI(Tl) detector output, the error percentage will be less than 20 and 10%, respectively.

Fluorouracil (5-FU) is one of the most essential drugs, and widely used to treat different types of cancers. However, direct injection of 5-FU causes many inevitable side effects, and therefore, the design of new and targeted drug delivery methods can reduce such undesirable effects. In the present work, density functional theory methods at B3LYP-D3(BJ)/6-31 g* level of theory were used to study the pristine and Al, Ga, P and As doped monolayer boron nitride (BN) nanosheets, as possible adsorption substrates for modern and targeted nanotechnology based drug delivery methods. Natural bond orbitals and quantum theory of atoms in molecules analyses were further used to reveal the physicochemical nature of the adsorption process. It was found that, adsorption process is endothermic in all studied cases, and the interactions energies are in the range of physisorption for pristine, P and As doped BN nanosheets, whereas, the chemical absorption of the 5-FU on Al and Ga doped nanosheets was obtained with adsorption energies of À 45.7 and À 46.3 kcal/mol, respectively. The calculated solvation energies also show that, the dissolution of the 5-FU/nanosheet complexes in water is more than the pristine nanosheets. The overall results confirm the great potential of the studied nanosheets and specially Al and Ga doped BNNSs as promising drug delivery substances in modern targeted drug delivery methods for 5-FU drug.

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