Bio-inspired compound feet with spines and foot pads were made to improve the take off performance of the Flea, a jumping robot that can jump 30 times its body length. A no-slip model of the flea was used to compare the performance of the flea with and without spines and foot pads on styrofoam, sandpaper 60Cw, and Teflon. On styrofoam, the flea with spines increased its kinetic energy by 65%, b...

Thirty-five consecutive patients with ventricular septal defect (VSD) associated with aortic insufficiency (AI) who underwent corrective surgery are presented. There were seven operative and three late deaths among the patients operated upon before 1968. No death, however, was encountered among the most recent 18 consecutive patients. The VSD was closed directly in 14 patients and with a Teflon...

In this work we report on progress in the development of models for a Micro-Pulsed Plasma Thruster (μPPT) and its exhaust plume. As a working example we consider a μPPT developed at the Air Force Research Laboratory. This is a miniaturized design of the axisymmetric PPT with a thrust in the 10 μN range that utilizes Teflon as a propellant. The plasma plume is simulated using a hybrid fluid-PIC-...

A superhydrophobic behavior can be obtained by properly modifying the surface topography of Teflon or other fluorinated polymers having an inherent hydrophobic character. According to this strategy, we have micro/nanotextured Teflon both as plane material (sheets) and as three-dimensional (3D) object (spheres) with a single step plasma process. The obtained textured Teflon samples were compared...

When a thermopile is used to measure the heat production of isolated muscle, the muscle is surrounded by gas saturated with water vapour, initially in equilibrium with the muscle. After contraction, the osmolarity of the muscle is raised so that it is no longer in equilibrium with the gas around it, and condensation will occur. When artificial muscles of known osmolarity were placed on a thermo...

Control of surface wetting properties to produce strongly hydrophobic or hydrophilic effects is at the heart of many macro- and microfluidic applications. In this work, we have investigated coaxial electrospinning to produce core-sheath-structured nano/microfibers that combine different properties from individual core and sheath materials. Teflon AF is an amorphous fluoropolymer that is widely ...

OBJECTIVE The purpose of this paper is to present the late clinical results of mitral valve repair with the "Double Teflon" technique. METHODS "Double Teflon" technique consists of a quadrangular resection of the posterior leaflet, annulus plication with "pledgetted" stitches over a Teflon patch, and leaflet suture. Between 1994 and 2003, 133 patients with degenerative mitral insufficiency du...

background & objectives: the aim of this study was to compare the effectiveness of two stapes prostheses in hearing improvement of patients undergoing stapes surgery for otosclerosis.   materials & methods: in this retrospective and descriptive study, the charts of 291 stapedectomies performed by one surgeon (first author) from 1997 to 2011 in imam khomeini and apadana hospitals of ahva...

We have measured the transmission of microwave radiation through a nearly cubic metal-wire network with a lattice constant of 1 cm and a length of 8 cm on each side. We observe a sharp drop in the transmission below a cutoff frequency nc59.33 GHz when the structure is empty. The gap persists when the network is filled with randomly positioned Teflon spheres, but nc is reduced by the ratio of th...