Gamma / neutron radiation shielding, structural and physical characteristics of iron slag nanopowder.

The current study explores the effectiveness of an iron slag nanopowder (ISNP), which prepared from local iron steel industry, against gamma/neutron shielding. The structural and physical characteristics were experimentally determined. The crystal structure, morphology and elemental composition of the ISNP were studied using X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX). On the other hand, a comprehensive experimental and theoretical study on the γ-ray shielding effectiveness of the ISNP was performed. In which, the experimental results have been validated by comparison with theoretical data which obtained by using the WinXcom program. This paper uses the well-known mathematical relationships to derive many shielding and dosimetry parameters such as effective atomic number and, effective electron density, for photon interaction and photon energy absorption as well as the γ-ray kerma coefficient from the mass attenuation coefficient. The exposure and energy absorption buildup factors have been also calculated. Furthermore, the shielding effectiveness against thermal and fast neutrons has been tested in terms of total macroscopic cross-sections. The results have revealed that the produced ISNP, with crystallite size of 24.5 nm, exhibits good shielding characteristics. Finally, based on this preliminary study, we can have concluded that the iron slag nanoparticles can be suitably used as an effective and safe (lead - free) component for radiation shielding.

RETROSPECTIVE ANALYSIS OF PATIENT RADIATION DOSES IN DIGITAL CORONARY ANGIOGRAPHY AND INTERVENTIONS.

This study sought to assess patient and operator eye lens doses in diagnostic coronary angiography (DCA) and percutaneous coronary interventions (PCI) in a University hospital in Oman. Kerma area product (PkA), cumulative air kerma (CAK) and fluoroscopic time (FT) were retrospectively recorded from the DICOM header for 264 patients. The median (interquartile range) of FT, PKA and CAK were: 5.3 min (2.6-10.5), 60.9 Gy cm2 (41.3-91.4) and 0.86 Gy (0.61-1.29), respectively, for DCA procedures, and they were 20.2 min (13.3-30.1), 174.0 Gy cm2 (113.7-253.3) and 2.6 Gy (1.8-3.9), respectively, for PCI procedures. The results revealed wide variability in patient doses among individual patients. Monitoring and recording patient dose data can be valuable for quality assurance and patient safety purposes. Feedback to the operator may help optimize radiation doses to patients and prompt further action, as needed.

PIXE study on the effects of parathyroid hormone on elemental content in rat bones.

Parathyroid hormone (PTH) has attracted considerable interest as a bone anabolic agent. PTH plays a central role in regulating calcium phosphate metabolism and its increases in production in response to low serum calcium levels. A continuous hypersecretion of PTH, as occurs in primary hyperparathyroidism, leads to bone resorption. In this study, the effect of different doses of parathyroid hormone (PTH) on bone mineral content (BMC) in rats was investigated by particle-induced X-ray emission (PIXE). This study will help in investigating further the toxicity of extremely high doses of PTH on BMC. For this study, PTH at doses of 15, 45, or 135µg/kg/day were applied to 9-month-old male and female Sprague Dawley (SD) rats. The concentrations of calcium (Ca), phosphorus (P), strontium (Sr), and zinc (Zn) were measured for bone treatment of PTH. From the results of the research, it was revealed that the biomechanical characteristics of the bone as well as the bone mass were enhanced after the treatment. It was further found that the concentrations of other elements also increased, excluding Zn. This research proved that PTH assists in the treatment of osteoporosis as revealed by the characteristics of different elements. PIXE can be used to determine the concentrations of bone mineral content.