A control system (12) for a power supply (14), such as a high voltage power supply, includes a control circuit (16) and a feedback circuit (18, 28, 30). The feedback circuit (18, 28, 30) is configured to produce a feedback signal indicative of the voltage of the power supply output. The control circuit (16) is configured to control the power supply (14) based on the feedback signal and a predetermined voltage value to maintain the output of the power supply (14) at about the predetermined voltag...

A method and apparatus for operating a mass spectrometer include providing at least two different ion sources, and coupling ion streams simultaneously from the at least two different ion sources to the spectrometer. Another method of operating a spectrometer includes a first coupling an ion stream from a first one of the ion sources into the spectrometer, next coupling an ion stream from a second one of the ion sources into the spectrometer, next coupling an ion stream from the second one of the...

The present invention is directed to a method of modulating the release of at least one endogenous compound in vivo. The method comprises delivering intranasally at least one micro-construct comprising an agonist and a pharmaceutically acceptable carrier to a locus comprising an agonist receptor and a heterologous receptor that is coupled to at least one common signaling molecule. The micro-construct used in the present inventive method provides sustained release of the agonist provided by erosi...

An arrangement for performing chromatography with a mobile phase and a chromatographic bed having a stationary phase is provided. The arrangement includes a support assembly configured to support the stationary phase. The support assembly has a sealed cavity configured so that when the support assembly is supporting the stationary phase a portion of the chromatographic bed and the stationary phase extends into the sealed cavity. The arrangement further includes a bladder having a void defined th...

The invention provides novel tetradentate enediyne ligands that are themselves thermally stable, yet react at about room temperature or slightly higher upon addition of metal ions or under photothermal conditions. In another aspect of the invention, a method of treating a disorder in a mammal comprising administering a therapeutically effective amount of a compound or composition is provided. In addition, the free ligand can be delivered to the mammal prior to complexation to metals, such that t...

A MALDI mass spectrometer directs a laser shot onto a MALDI sample to generate a sample spectrum which is analyzed to determine if the sample spectrum meets a predetermined criteria. If so, subsequent laser shots are directed to predetermined locations on the MALDI sample. In essence, if the analysis of a previous laser shot indicates that a "sweet spot" of the MALDI sample has be located, subsequent laser shots may be directed to areas proximate to the previous shot thereby allowing the sweet s...

A circuit and method for generating a delayed event following a trigger pulse occurring at a random time between clock pulses is disclosed. The circuit includes a clock circuit, a voltage converter, an analog-to-digital converter circuit, a memory storage circuit, and a summing circuit. The method includes representing the time between the triggering pulse and a subsequent clock pulse as a voltage, converting the voltage to a stored digital value, and defining a desired delay time by adding a fi...

Disclosed are chiral organic compounds and metal coordination complexes thereof having C.sub.2 symmetry.

The present invention includes the receptor protein 4-1BB and the cDNA gene encoding for receptor protein 4-1BB. The nucleotide sequence of the isolated cDNA is disclosed herein along with the deduced amino acid sequence. The 4-1BB protein and fragments and derivatives can be used: 1) as a probe to isolate ligands to receptor protein 4-1BB, 2) to stimulate proliferation of B-cell's expressing 4-1BB, or 3) to block 4-1BB ligand binding. A monoclonal antibody against 4-1BB was developed which spec...

A portable, lightweight digital imaging device uses a slit scanning arrangement to obtain an image of the eye, in particular the retina. The scanning arrangement reduces the amount of target area illuminated at a time, thereby reducing the amount of unwanted light scatter and providing a higher contrast image. A detection arrangement receives the light remitted from the retinal plane and produces an image. The device is operable under battery power and ambient light conditions, such as outdoor o...