BACKGROUND Ultrasonography use is increasing in emergency departments, and ultrasound education is now recommended in resident training. Ultrasound phantoms are used in many institutions for training purposes. The purpose of this study is to describe an inexpensive and simple method to create ultrasound-imaging models for the purpose of education and practice using clear ballistic gel. METHOD...

We report studies of the motion of cold atoms in a time-dependent optical potential. The dynamics of our system are that of the quantum kicked rotor, and exhibit a wide variety of phenomena. One purely quantum effect is the quantum resonance, which occurs for well-chosen initial conditions and specific values of the period between kicks. Distinctly nonclassical behavior, such as ballistic growt...

Bartumeus et al. [Phys. Rev. Lett. 88, 097901 (2002)] compared the efficiency of a Lévy random walk predator strategy with a Brownian random walk strategy in a periodic one-dimensional domain with nonrevisitable moving targets. Their findings from numerical simulations conclude that "a Lévy search strategy is the best option in some, but not all, cases for a random search process." Using the sa...

Personal protective equipment worn by uniformed services (e.g., the police and the military) must ensure protection against bodily injuries. However, a high degree of protection is always associated with significant discomfort. This article presents the results of an assessment of the ergonomics parameters of new special purpose products, ballistic inserts with improved ballistic resistance, an...

The two-component model is a human movement model in which an aimed movement is broken into a voluntary ballistic movement followed by a corrective movement. Recently, experimental evidence has shown that 3D aimed movements in virtual environments can be modeled using the two-component model. In this paper, we use the two-component model for designing 3D interaction techniques which aim at faci...

We ana/lyze the performance of a recently reported Ge/Si core/shell nanowire transistor using a semiclassical, ballistic transport model and an sp3d5s* tight-binding treatment of the electronic structure. Comparison of the measured performance of the device with the effects of series resistance removed to the simulated result assuming ballistic transport shows that the experimental device opera...

OBJECTIVE To evaluate the role of ballistic ureteroscopic lithotripsy in children with ureteral stones. MATERIALS AND METHODS Children under 14 years with ureteral stones were treated with ureteroscopy in a 5-year period in our institution. RESULTS Twenty-three procedures were performed in 20 children. Mean surgical time, age and stone size were 31 min. (15 - 120 min.), 11 years. (4-13 year...

The large-scale TsNIIMASH ballistic facility was built in 1992 through modernization of the large shock tunnel. Having 0.5 m caliber, the facility is 200 m long. Each experiment on the facility envisages an explosion of stoichiometric hydrogen-oxygen mixture, up to 300 cub. m by volume. In the air-evacuated ballistic channel 60 m long, the expanding explosion products of the detonating gas mixt...

Dr. James Clay Moltz is Assistant Director and Research Professor at the Center for Nonproliferation Studies of the Monterey Institute of International Studies. He has published widely on Russian Far Eastern and East Asian security issues. The rise of theater ballistic missile capabilities in East Asia—particularly in China and North Korea—has raised fears among the United States, South Korea, ...