Abstract: A SCUBA diving mask body is completely comprised of flexible material so that the mask can be folded into a small package. The inventive mask comprises a flexible rubber body which integrally incorporates the mask skirt. A rigid lens for each eye is inserted into a socket in the body. The mask strap is attached to the flexible body by means of two adjustable strap holders.

Abstract: Demonstration (demo) application software and various utility software programs are configured as a novel "protected demonstration environment" having layered security mechanisms for protecting the integrity of software executing on a computer. The security mechanisms include an underlying activity timer for ensuring that the demo program is periodically running in the absence of user input activity. When the demo program is not running, additional security mechanisms, such as message filters and icon disablers, are provided to reduce the vulnerability of the system. These security mechanisms cooperate to provide users access to certain innocuous features of the software through a graphical desktop interface on a computer screen, while preventing access to potentially destructive features.

Abstract: An improved self-lubricating catheter and guidewire introducer is provided with a reservoir containing lubrication fluid located proximally of a sealing gasket in a modified end cap. An improved self-sealing gasket provides hemostasis while reducing the force required to move a catheter or guidewire positioned within the gasket.

Abstract: A method of reducing radiation damping during free induction decay in NMR measurements of samples having a narrow line width uses the active switching of the quality factor value of the coil circuit of an NMR detection probe. After application of an excitation pulse to the sample, data acquisition is accomplished in periodic samples. The Q of the coil circuit is set to a high value while each sample is being taken, but is reduced significantly in between samples by detuning the coil circuit. Minimization of the high-Q state of the coil circuit and maximization of the difference between the high Q value and the low Q value greatly decrease the detrimental effects of radiation damping on free induction decay. The coil circuit Q is modified automatically by the application of a Q switching signal generated by a controller, such as a computer which controls other aspect of the NMR experiment.

Abstract: A golf putter is provided having a head and shaft. The head is provided with spaced-apart weights which extend at least about 35% of the maximum distance between the front face and back edge of the head. The shaft enters the head at a point at least about 65% of the length of the putter away from the front face. The shaft is angled toward the front face of the head and toward a user grasping the shaft.

Abstract: Heavy metal ions react with iron particles in acidic aqueous solution to form heavy metallic particles that are suitable for recycling and reuse when recovered from the aqueous solution. Chelating agents that are present are deactivated by bonding to ferrous ions produced from the iron particles. An alkali metal hydroxide is utilized to precipitate remaining heavy metal ions including ferrous and ferric ions which are recycled to the acidic aqueous solution.

Abstract: A dilatation balloon having at least one helical groove disposed in at least a portion of the dilating surface of the dilatation balloon is mounted on the distal end of a catheter shaft. Multiple helical grooves may be provided in the dilatation balloon extending parallel to each other or opposite to each other in the dilating surface. Each helical groove has a pitch, width and depth. According to one aspect of the invention, the pitch, width and depth of the helical groove, as well as the number of grooves, are selected to allow perfusion of blood past the dilatation catheter when the dilatation balloon is inflated in a blood vessel. According to another aspect of the invention, the pitch, width, and depth of the helical groove, as well as the number of grooves, are selected so that the dilatation balloon conforms to a tortuous blood vessel and does not straighten the blood vessel during dilation.

Abstract: A method of shimming an NMR magnet uses a plurality of 1D projections through a sample volume to determine the inhomogeneities of the field of the NMR magnet. The frequency distributions obtained are assembled from the phase signals of the various projections. In order to avoid frequency errors due to phase wrapping, the phase of each signal is monitored over time for discontinuities indicative of aliasing. For each phase wrap, the signal is "unwrapped" by adjusting the value of the phase signal by 2.pi.. The same method is used to establish a shim field map for each of the shim coils being used. With one shim coil at a time being driven with a predetermined current, the detection method is repeated to acquire a shim-base frequency map for each shim coil. The base frequency map is then subtracted from the shim-base frequency maps to obtain shim field maps. The proper shim currents are then acquired through matrix operations on the shim field maps and the base frequency map.

Abstract: A nuclear magnetic resonance cross polarization probe uses a dual-coil arrangement in which a single-turn inner coil is surrounded by a solenoid coil. The inner coil is tuned to the frequency of a relatively high Larmor frequency nuclei type, such as proton. The solenoid coil is tuned to a lower Larmor frequency nuclei type. An inner sample region surrounded by the inner coil has a first magnetic field component induced by an electrical signal at the relatively high frequency in the inner coil. An electrical signal at the lower frequency is input to the solenoid coil and results in the generation of a magnetic field alternating at the lower frequency. This field induces a current in the inner coil at the lower frequency that, in turn, induces a magnetic field component in the inner region at the lower frequency.

Abstract: A sample changer for a spectrometer of the type having a generally vertical sample loading air shaft in which an upflowing air stream is present. The sample changer includes a support for positioning at the spectrometer and a carriage movably supported by the support which carriage has an array of generally vertical passages extending entirely through the carriage, those passages being adapted to contain sample holders. The sample changer also includes an actuator for moving the carriage relative to the support to position each passage over the air shaft so that that passage becomes an extension of the air shaft whereby the sample holder in that shaft may be buoyed up and supported in its passage by the air stream from the airshaft.

Abstract: A unique vehicle ID number and other verification information is stored in a small memory mounted on a tank truck. When the truck is connected to a loading terminal by means of a cable which is used by an existing overfill/ground system, an interface circuit connected between the memory and the cable prevents signals which are normally found on the cable leads from damaging the memory circuits. When information must be read from the memory, a special identification and verification system connected to the overfill/grounding circuits modifies some of the normal signals on the cable in order to activate the on-board memory and retrieve the stored information without disabling the overfill and ground proving capabilities.

Abstract: B.sub.1 (RF) gradient echo pulse sequences are combined with frequency-selective pulse sequences to selectively suppress a solvent resonance signal by preventing the formation of an echo for the solvent resonance, while allowing the formation of an echo for the sample resonances under study. The RF gradient pulses may be planar or radial pulses. A pulse sequence for suppressing a solvent resonance signal in NMR experiments comprises a pair of (RF) gradient pulses which sandwich a selective inversion pulse sequence. In accordance with one embodiment of the invention, the RF gradient pulses are anti-symmetric (have opposite phase) and the selective inversion pulse sequence comprises a homogeneous frequency-selective inversion pulse, such as a .pi. pulse, applied in time between the two RF gradient pulses.

Abstract: A software reverberator system produces a sequence of "reverberated" samples from an input digital word sequence where each word in the input sequence comprises a digitized sample of an original analog audio signal. The invention generates the reverberated samples by adding together several scaled and delayed input words to produce a corresponding reverberated output word. The resulting reverberated output word stream can be converted to analog form in sequence to produce a reverberated version of the original audio signal. The delays are produced by clocking the input words through multi-stage first-in, first-out buffers with a number of stages selected to give the desired delay.

Abstract: An digital video image processing system employs codes of various lengths to encode the luminance information within the digital video images. The inventive method and apparatus divides a video image into non-overlapping regions containing a plurality of pixels with luminance values. Within each region, the method computes the total luminance variation across the region, the direction of greatest luminance change within the region, the base, or lowest, luminance value within the region and the location and type of luminance transition within the region. Depending on the variation of the luminance values within a region and on the quality desired in the decoded image, the computed information is used to encode the luminance values in short, medium, or long codes. The luminance codes may be predetermined and unchanging or they may vary from image to image or within given images.

Abstract: A powered planing catamaran has a pair of asymmetric V-bottom hulls such that the inner surfaces of each of the hulls defines less of a deadrise angle than the outer surfaces. The inner surfaces define the primary running and planing surfaces. The bridging structure that connects the hulls defines an inverted tunnel-like channel that is broader at the bow end of the boat than the aft end and which defines an essentially inverted U-shaped configuration from amidships aft. A V-shaped nacelle is formed at the bow end of the underside of the bridging structure and is configured to dampen the slamming effect of waves at low speeds. At planing speeds, the nacelle is out of the water.

Abstract: An improved self-sealing gasket provides hemostasis while reducing the force required to move a catheter or guidewire positioned within the gasket. Slits formed on one surface of the gasket intersect with a central aperture formed on the opposite face of the gasket. An annular ring formed on the gasket assists in retaining the gasket within a catheter introducer. An annular shelf may be provided distally of the gasket to prevent dislodgement of the gasket if an instrument is inserted into the introducer off axially.

Abstract: A composite RF pulse is created from a sequence of conventional homogeneous RF pulses and conventional gradient RF pulses and the composite pulse generates a gradient magnetic field with a spatially varying amplitude, but a spatially independent phase. In one embodiment of the invention, the pulse sequence consists of four conventional gradient RF pulses interspersed with two conventional homogeneous RF pulses. In another embodiment of the invention, a conventional gradient RF pulse is combined with a conventional homogeneous RF pulse and the pulse pair is repeated in order to generate an effective magnetic field with a spatially varying amplitude, but a spatially independent phase.

Abstract: A portable decking system formed from a plurality of flat panels adapted to be placed directly on the ground is provided with special clips that facilitate interconnection of adjacent edges of adjacent panels. The clips are generally W-shaped in cross-section to define a pair of channels each of which is receptive to a frame member of a flat panel. The clips are constructed to securely connect the panels together but in a manner that enables their ready detachment, all of which may be accomplished without tools or additional fasteners.

Abstract: In an AC-powered power supply with a bipolar controller V controlling the instantaneous value of a control quantity measured by a sensor F.sub.1 to a predetermined setting within a deviation of less than 0.1% at 1 Hz via the output DC current I.sub.o, and with an adjustable rectifier EQ followed by a charging inductance L.sub.1 and a filter capacitor C.sub.1, whereby the output of controller V is electrically connected to the output line of the power supply, the output of controller V is AC-decoupled from filter capacitor C.sub.1 by a decoupling inductance L.sub.2, two potentials V.sub.o +V.sub.1 and V.sub.o -V.sub.2 are supplied to controller V, and a sensor F.sub.2 is provided for the output current I.sub.2 of controller V, which feeds an output signal to a control unit CTR which controls rectifier EQ in such a way that the mean value of output current I.sub.2 of controller V is regulated to a minimum value.