BACKGROUND The propeller flap is defined as (1) being island-shaped, (2) having an axis that includes the perforators, and (3) having the ability to be rotated around an axis. The advantage of the propeller flap is that it is a pedicle flap that can be applied to cover defects located at the distal ends of the extremities. The specific aims of the authors' study were (1) to evaluate the usefuln...

Almost all computational fluid dynamics (CFD) simulations of flow around marine propellers use turbulence models that are only well suited for fully turbulent flows, which in some cases may lead to accuracy degradation in the prediction of propeller performance characteristics. The discrepancy between computed thrust and torque and corresponding experimental data increases with increasing prope...

BACKGROUND AND PURPOSE MR diagnostic of postoperative recurrent cholesteatomas is difficult. Our purpose was to compare multishot fast spin-echo periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) diffusion-weighted MR imaging (DWI) with array spatial sensitivity encoding technique (ASSET) single-shot echo-planar DWI and late postgadolinium T1-weighted MR im...

The DDB1-Cul4A ubiquitin ligase complex promotes protein ubiquitination in diverse cellular functions and is reprogrammed by the V proteins of paramyxoviruses to degrade STATs and block interferon signaling. Here we report the crystal structures of DDB1 alone and in complex with the simian virus 5 V protein. The DDB1 structure reveals an intertwined three-propeller cluster, which contains two t...

Abstract This paper presents a novel conceptual design method for electric and hybrid propulsion systems in small aircraft. The effects of key parameters on the system performance are analyzed advantages drawbacks investigated discussed basis two sets thrust requirements. First, general algorithm is outlined. followed by description three investigated: fully electric; parallel hybrid; conventio...

Speed and position control systems for marine vehicles have been subject to an increased focus with respect to performance and safety. An example is represented by drilling operations performed with semi submersible rigs where the control of position and heading requires high accuracy. Drifting from the well position could cause severe damage to equipment and environment. Also, the use of under...

Speed and position control systems for marine vehicles have been subject to an increased focus with respect to performance and safety. An example is represented by drilling operations performed with semi submersible rigs where the control of position and heading requires high accuracy. Drifting from the well position could cause severe damage to equipment and environment. Also, the use of under...

This study investigates the unsteady dynamics and inherent instabilities of a cavitating propeller operating in a water tunnel. First, the steady characteristics of the cavitating propeller such as the thrust coefficient are obtained by applying continuity and momentum equations to a simple one-dimensional flow tube model. The effects of the tunnel walls as well as those of the propeller operat...

This paper deals with the estimation of propulsive effects for a three-lifting surface turboprop aircraft concept, rear engine installation at horizontal tail tips, conceived to carry up 130 passengers. work is focused on how system affects tailplane aerodynamics and, consequently, aircraft’s static stability characteristics using wind tunnel tests. Both direct and indirect have been estimated....

BACKGROUND AND PURPOSE Fluid-attenuated inversion recovery hyperintense vessels in stroke represent leptomeningeal collateral flow. We presumed that FLAIR hyperintense vessels would be more closely associated with arterial stenosis and perfusion abnormality in ischemic stroke on T2-PROPELLER-FLAIR than on T2-FLAIR. MATERIALS AND METHODS We retrospectively reviewed 35 patients with middle cere...