Cancer risk at low-dose ionizing radiation has been the subject of great scientific controversy in the past century. The clear majority of national and international radiation protection regulators adopt the linear no-threshold (LNT) model based on the atomic-bomb survivors Life Span Study (LSS) for solid cancer risk assessment. The LNT...
The social sciences have the capacity to contribute to natural resource management through investigations of human dynamics associated with the environment. Sense of place (SOP), the formed relationships between an individual and the environment, has been considered a fundamental aspect of human well-being and can contribute to more holistic understanding...
The purpose of this research was to develop and test a radiation detector to perform beta dosimetry and spectroscopy. The detector utilizes plastic scintillator volumes to produce scintillation light in proportion to the amount of energy deposited in them, and a large-area avalanche photodiode to convert the light to electrical...
Tissue weighting factors, w[subscript T], used to convert equivalent dose to effective dose, account for differences in radiosensitivity of various organs in the human body and allow users to compare individual organ detriment to whole body risk. They are explicitly calculated in ICRP 26, 60, and 103, although the methods...
The recent reductions to the international dose limit recommendations for the lens
of the eye have renewed interest in radiation protection strategies in interventional
fluoroscopy, where eye-lens radiation exposure occurs frequently. Radiationshielding
eyewear can significantly reduce lens dose in these scenarios, but accurate
protection factors are elusive because they depend...
To quantify the relative activity contributions of beta emitters in mixed emission source spectra, the triple-layer phoswich detector was modeled to generate beta energy absorption spectra from mixed beta sources. These mixed sources include four pure beta emitters (C-14, Tc-99, Sr-90, and Y-90). Monte Carlo N-Particle (MCNP) computer code was...
International recommendations provided by the International Commission on Radiation Protection (ICRP), as well as national regulations, set by the U.S. Nuclear Regulatory Commission (NRC), state that the exposure of skin to highly concentrated radioactive sources should be monitored at specified depths in skin and kept below specific dose equivalence levels....
Bioprocessing design includes optimizing unit operations in a process in order to attain a desired amount of product. Process economics, safety, environmental impact, and product quality are considered. This study investigated which skills and conceptual knowledge related to bioprocessing design were most important for entry-level engineers in the bioprocessing industry....