Abstract: An adaptive controller for delivering fractional inspired oxygen to a patient. The controller utilizes a pulse oximeter connected by an optical sensor to the patient for measuring the patient's blood hemoglobin saturation and pulse rate. Signals from the oximeter are used by a calculator for determining the fractional inspired oxygen level to be delivered to the patient. The calculated percentage of oxygen is provided to the patient so that the gas taken in by the patient automatically causes the blood in the patient to reach a predetermined hemoglobin saturation level which adapts to the patient's requirements. The calculator is programmed to determine when there is an excess deviation of the patient's pulse rate. When an excess deviation is detected, the fractional inspired oxygen level to the patient is fixed until the excess deviation of the pulse rate has been terminated.

Abstract: A device and method for rapidly performing automatic magnet shimming using algebraic techniques, based on field maps computed by phase measurement within Carr-Purcell echo sequences. The correction computation for determining shim currents is carried out by a linear programming algorithm which compensates field inhomogeneities within the sample by a linear combination of all the shims. The procedure is non-iterative, thus avoiding instability problems and improving speed performance.

Abstract: A multiple tuning NMR probe includes a radio frequency (RF) probe tuned by means of a circuit which creates a multiple pole circuit response in the probe, each of the poles being sufficiently separated from each other as to cause resonance of the probe at distinct frequencies. When tuning for nuclei with resonances substantially apart, this function may be accomplished using a parallel capacitor-inductor (L-C) trap with an impedance matching network. When tuning for nuclei with substantially closely spaced resonances, a tank circuit is used which has a single resonance which is split into two resonances by strongly coupling it to another tank circuit in resonance with the sample coil tank circuit.