A fully nonlinear modal analysis identifies a critical centerline wave number q(c) for river meandering that separates long-wavelength bends, which grow to cutoff, from short-wavelength bends, which decay. Exact, numerical, and approximate analytical results for q(c) rely on the Ikeda, Parker, and Sawai [J. Fluid Mech. 112, 363 (1981)] model, supplemented by dynamical equations that govern the ...

A method for creating planar As2S3 waveguides with a minimum of processing steps is proposed, and the resulting waveguides have been characterized. When the processing parameters are optimized, the losses are low enough for practical use. The authors demonstrate this by creating serpentine waveguides with multiple bends and lengths in excess of 23cm. Keywords-component; chalcogenide glass; opti...

The registration and alignment of a monolayer of microdomains in a self-assembled block copolymer thin film can be controlled by chemical or physical templating methods. Although planar patterns are useful for nanoscale device fabrication, three-dimensional multilevel structures are required for some applications. We found that a bilayer film of a cylindrical-morphology block copolymer, templat...

During the past decade, the issue of strong bending of the double helix has attracted a lot of attention. Here, we overview the major experimental and theoretical developments in the field sorting out reliably established facts from speculations and unsubstantiated claims. Theoretical analysis shows that sharp bends or kinks have to facilitate strong bending of the double helix. It remains to b...

III. Geometry There are three logically independent facets to calculating the transfer map through a bend magnet: physics, geometry, and representation. We will derive the exact map for transit through ideal bends while separating these three, esp., isolating the geometry problem from the other two.

This study investigated whether the "constant limb force" hypothesis can be applied to bend sprinting on an athletics track and to understand how force production influences performance on the bend compared with the straight. Force and three-dimensional video analyses were conducted on seven competitive athletes during maximal effort sprinting on the bend (radius 37.72 m) and straight. Left ste...

At present, no decompression algorithm is able to predict safe decompression for all dive scenarios. In practice, empirical adjustments are made by experienced organisations or divers in order to improve decompression profiles for the range of depths and durations needed on any particular dive. Bubble formation and growth in the human body are the fundamental causes of decompression sickness, a...

OBJECTIVES/HYPOTHESIS Scuba diving may cause severe hearing loss and vertigo due to inner ear barotrauma and decompression sickness. These may be difficult to differentiate clinically. Decompression sickness requires costly and potentially dangerous hyperbaric therapy, whereas such treatment may worsen barotrauma. The objective of this study was to assess the potential utility of magnetic reson...

OBJECTIVE To describe the rehabilitation outcome of a case of spinal decompression sickness presenting as partial Brown-Sequard syndrome treated with robotic-assisted body-weight support treadmill training. STUDY DESIGN Case report. BACKGROUND Type II decompression sickness patients commonly suffer from myelopathy with gait disturbances necessitating rehabilitation. Robotic-assisted body-we...

The kink turn (K-turn) is an RNA structural motif found in many biologically significant RNAs. While most examples of the K-turn have a similar fold, the crystal structure of the Azoarcus group I intron revealed a novel RNA conformation, a reverse kink turn bent in the direction opposite that of a consensus K-turn. The reverse K-turn is bent toward the major grooves rather than the minor groove...