Abstract: The disclosed electrometer is of the type including an integrating amplifier and an electronically controlled switch. When the switch is closed, the electrometer is reset or cleared, and when the switch is open, the amplifier operates as an integrator. The switch is configured to substantially eliminate leakage currents between the switch and the inputs of the amplifier. The electrometer is operative for very small input currents and is operative over a wide dynamic range. The disclosed electrometer may be used to implement a highly accurate pressure transducer.

Abstract: Multi-lumen balloons for use as or in conjunction with balloon dilation catheters, and methods for making such balloons, are disclosed.

Abstract: An apparatus for mounting a magnetometer including a frame and a platform mounted for rotation within the frame. The magnetometer and one or more counterweights are mounted within the platform such that gravity acting on the counterweights maintains the magnetometer in a horizontal orientation. A first coil is coupled in parallel with the magnetometer and is wound around the perimeter of the platform. A second coil is wound around the perimeter of the frame such that the first and second coils form an air core transformer. The second coil terminates in two terminals which provide a communication port. A sensing circuit coupled to the port electrically communicates with the magnetometer via the inductive coupling provided by the transformer. In alternative embodiments, each of the first and second coils is implemented as two coils with associated diodes.

Abstract: A liquid vaporizer includes a stack of coaxially aligned, thermally conductive, thin, flat disks having different diameters. The larger diameter disks each include at least one aperture and preferably a plurality of closely spaced apertures radially located a predetermined distance from the center of the disk. The vaporizer further includes means for establishing a liquid film on at least a portion of the surfaces of the larger diameter disks and for accelerating the vaporization of the liquid thereon by passing a gas through the apertures of the larger diameter disks over the liquid film on the portion of the surfaces of the larger diameter disks.

Abstract: In a medical imaging system having a data acquisition system (DAS) that provides both image data and non-image data to a main computer of the medical imaging system via a plurality of DAS channels, wherein the DAS channels convey mostly image data, a method and apparatus is provided for selectively sampling and multiplexing auxiliary (AUX) data, such as system monitoring and system diagnostic data, and providing the AUX data along with the image data to a bank of analog-to-digital converters. A plurality of programmable sampling and multiplexing modes are provided so as to ensure that each AUX data signal is sampled at a rate that is appropriate to a phase of operation of the medical imaging system, such as system monitoring, or system diagnostics.

Abstract: An apparatus for compensating for drift of the focal spot of an X-ray radiation source used in a tomography system is disclosed so as to maintain a primary collimated beam of radiation emanating from the focal spot aligned with target detectors of the tomography system. A second collimated beam of radiation is produced from the same focal spot and directed along a different axis from the first beam. An array of detectors track the movement of the second collimated beam and produce signals which are used to reposition the collimator used to collimate the primary beam so as to maintain the primary beam substantially aligned with the target detectors.

Abstract: Disclosed are stabilized ribozyme analogs having the ability to endonucleolytically cleave a sequence of 3' to 5' linked ribonucleotides. These ribozyme analogs include modifications at specific loop, catalytic core, and flanking region nucleotides which makes them more resistant to nucleases. Also disclosed are methods of preparing and utilizing the ribozyme analogs of the invention, and pharmaceutical formulations and kits containing such ribozyme analogs.