In this study, the gamma ray shielding properties of shields prepared from polyvinyl alcohol as a base material reinforced with barium sulfate nanoparticles at different reinforcement ratios (5,15,25,35,45 %) and thickness 1 cm were studied. To determine acceptability these for use in protection, some parameters including linear attenuation coefficient (μ), mean free path (λ), half value layer ...

A vast array of instruments are available for measuring disease activity in juvenile idiopathic arthritis (JIA). However, due to the high variability in the clinical presentation and course of JIA, no single measure can reliably capture disease activity in all patients. On the other hand, assessment of all measures individually may cause methodological and statistical problems, especially when ...

Active learning hands-on activities improve students’ learning. More active learning tools, approaches and activities for the engineering curriculum are critical for the education of the next generation of engineers. A new methodology specifically aimed at the creation of handson active learning products (ALPs) has been developed and is described in detail with examples. Methodology provides gu...

We report the first demonstration to our knowledge of broadly tunable, single-frequency operation of a cw Cr:YAG laser. Single-frequency operation was obtained from 1332 to 1554 nm with a maximum output power of 680 mW generated at 1457 nm with 10% conversion efficiency of 1047-nm pump laser radiation. A traveling-wave ring resonator was forced to operate unidirectionally by use of Faraday rota...

Hydration free energy calculations have become important tests of force fields. Alchemical free energy calculations based on molecular dynamics simulations provide a rigorous way to calculate these free energies for a particular force field, given sufficient sampling. Here, we report results of alchemical hydration free energy calculations for the set of small molecules comprising the 2011 Stat...