The X-Ray fluorescence parameters and radiation shielding efficiency of silver doped superconducting alloys

The Kβ/Kα X-ray intensity ratios of Cu and Ag in Cu-Ag thin alloy films

Kβ/Kα X-ray intensity ratio values of Cu and Ag in CuxAg1-x (x = 53.5, 67.6, 76.9, 85.4, 89.6) thin alloy films produced from two different sources by the physical vapour deposition method have been determined by the Energy Dispersive X-ray Fluorescence Spectroscopy (EDXRF) method. The changes in the crystal structures of CuxAg1-x thin alloy films caused by the changes in the Cu and Ag concentrations, which affect the valence electronic structure have been investigated by the X-ray Diffraction (XRD) techniques. The obtained values were compared with the theoretical and fitted values for pure Cu and Ag elements.

A comparative neutron and gamma-ray radiation shielding investigation of molybdenum and boron filled polymer composites

This work presents a detailed radiation shielding study for polymer composites filled with Boron and Molybdenum additives. The chosen novel polymer composites were produced at different percentages of the additive materials to provide a proper evaluation of their neutron and gamma-ray attenuation abilities. The effect of additive particle size on the shielding characteristics was further investigated. On the gamma-ray side, simulation, theoretical and experimental evaluations were performed in a wide range of photon energies varying from 59.5 keV to 1332.5 keV with help of MC simulations (GEANT4 and FLUKA), WinXCOM code, a High Purity Germanium Detector, respectively. A remarkable consistency was reported between them. On the neutron shielding side, the prepared samples produced with nano and micron particle size additives were additionally examined by providing fast neutron removal cross-section (Σ_R) and the simulated neutron transmissions through the prepared samples. The samples filled with nano sized particles show better shielding capability than the one filled with micron sized particles. In other words, a new polymer shielding material that does not contain toxic content is introduced: the sample codded N-B0Mo50 exhibits superior radiation attenuation.

Targeting metabolic adaptations in the breast cancer-liver metastatic niche using dietary approaches to improve endocrine therapy efficacy

Estrogen receptor-positive (ER+) metastatic tumors contribute to nearly 70% of breast cancer-related deaths. Most patients with ER+ metastatic breast cancer (MBC) undergo treatment with the estrogen receptor antagonist fulvestrant (Fulv) as standard-of-care. Yet, among such patients, metastasis in the liver is associated with reduced overall survival compared to other metastasis sites. The factors underlying the reduced responsiveness of liver metastases to ER-targeting agents remain unknown, impeding the development of more effective treatment approaches to improve outcomes for patients with ER+ liver metastases. We therefore evaluated site-specific changes in MBC cells and determined the mechanisms through which the liver metastatic niche specifically influences ER+ tumor metabolism and drug resistance. We characterized ER activity of MBC cells both in vitro, using a novel system of tissue-specific extracellular matrix hydrogels representing the stroma of ER+ tumor metastatic sites (liver, lung and bone), and in vivo, in liver and lung metastasis mouse models. ER+ metastatic liver tumors and MBC cells grown in liver hydrogels displayed upregulated expression of glucose metabolism enzymes in response to Fulv. Furthermore, differential ERα activity, but not expression, was detected in liver hydrogels. In vivo, increased glucose metabolism led to increased glycogen deposition in liver metastatic tumors, while a fasting-mimicking diet increased efficacy of Fulv treatment to reduce the metastatic burden. Our findings identify a novel mechanism of endocrine resistance driven by the liver tumor microenvironment. Implications: These results may guide the development of dietary strategies to circumvent drug resistance in liver metastasis, with potential applicability in other metastatic diseases.