304 results about "Hourglass" patented technology

A bone fixation assembly for securing a fixation device such as a bone plate, to bone includes a fixation device, including at least a through hole with isolated protrusions (such as pegs or spikes); and locking bone engaging members such as screws. The screw has a shank with a thread for engaging bone and a partial sphere head with a thread configured and dimensioned to match with the isolated protrusions of the hourglass shaped through holes of the bone plate. The bone plate has a through hole shaped like an hourglass which diameter matches that of the screw spherical head and is provided with multiple isolated protrusions. In use, the screw is threaded into the bone, through the hole of the bone plate at a selected angle. The partial sphere head of the screw engages in the protrusions of the plate hole resulting in the strong locking of the screw at the selected orientation within the through hole in just one single surgical action.

A prosthetic heart valve having an anchoring sleeve that changes shape when the valve is implanted and contacts the surrounding annulus to prevent migration of the valve. The heart valve may be non-expandable and the anchoring sleeve may provide the primary anchoring structure of the valve. Alternatively, the valve may be expandable wherein the anchoring sleeve supplements the inherent anchoring capacity of the valve structure. The anchoring sleeve is at least partly made of a material that increases in size, i.e., swells, due to absorption of body fluids. For instance, the anchoring sleeve may be formed of an inner material that swells upon contact with body fluids enclosed by a cover. The anchoring sleeve desirably changes shape to provide spaced apart annular flanges for securing the valve around a fibrous annulus. An anchoring sleeve for a prosthetic heart valve having an expandable frame surrounds a majority of the frame and may define an external hourglass configuration.

A method and apparatus enabling increased sensitivity in ion mobility spectrometry / mass spectrometry instruments which substantially reduces or eliminates the loss of ions in ion mobility spectrometer drift tubes utilizing a device for transmitting ions from an ion source which allows the transmission of ions without significant delay to an hourglass electrodynamic ion funnel at the entrance to the drift tube and / or an internal ion funnel at the exit of the drift tube. An hourglass electrodynamic funnel is formed of at least an entry element, a center element, and an exit element, wherein the aperture of the center element is smaller than the aperture of the entry element and the aperture of the exit elements. Ions generated in a relatively high pressure region by an ion source at the exterior of the hourglass electrodynamic funnel are transmitted to a relatively low pressure region at the entrance of the hourglass funnel through a conductance limiting orifice. Alternating and direct electrical potentials are applied to the elements of the hourglass electrodynamic funnel thereby drawing ions into and through the hourglass electrodynamic funnel thereby introducing relatively large quantities of ions into the drift tube while maintaining the gas pressure and composition at the interior of the drift tube as distinct from those at the entrance of the electrodynamic funnel and allowing a positive gas pressure to be maintained within the drift tube, if desired. An internal ion funnel is provided within the drift tube and is positioned at the exit of said drift tube. The advantage of the internal ion funnel is that ions that are dispersed away from the exit aperture within the drift tube, such as those that are typically lost in conventional drift tubes to any subsequent analysis or measurement, are instead directed through the exit of the drift tube, vastly increasing the amount of ions exiting the drift tube.