Abstract: A method is disclosed for analyzing composition of a body part from nuclear magnetic resonance measurements made on the body part. The method includes exciting a predetermined sequence of nuclear magnetic resonance phenomena in the body part and measuring nuclear magnetic resonance signals from the body part. At least a part of the measured signals are composed into a measurement vector. The mass of the at least one constituent is determined as a predetermined function of the measurement vector. The predetermined function represents the at least one constituent and defines a standard for a range of at least one of compositional variations and temperature variations of the at least one constituent.

Abstract: A method is disclosed for analyzing body composition. The method includes inducing a static magnetic field in the body. The static magnetic field has a known distribution along a longitudinal axis of the body. A radio frequency magnetic field is induced in the body. The radio frequency and a bandwidth thereof are selected to induce nuclear magnetic resonance phenomena in a selected axial segment along the body. Nuclear magnetic resonance phenomena are from the selected axial segment. Composition is determined from the magnetic resonance signals. The measurement may be repeated in different axial segments by changing the static field amplitude or a frequency of the RF magnetic field. In some embodiments, a gradient field is superimposed over the static field.

Abstract: A method is disclosed for measuring whole body composition. The method includes confining movement of the body to a selected volume, inducing a static magnetic field in the volume, inducing a pulsed radio frequency magnetic field in the volume, and receiving nuclear magnetic resonance signals from the body. The resonance signals from any part of the body are substantially independent of a position of the body part within the volume. Whole body composition is assessed from the resonance signals.

Abstract: An electromagnetic wellbore logging tool including an elongated sonde adapted for traversing the wellbore, a source of alternating current, an antenna connected to the source of alternating current, and a receiver circuit connected to the antenna. The receiver circuit provides an output corresponding to electromagnetic signals induced in the antenna. The invention includes at least one insulating insert disposed in an annular space between the exterior of the sonde and the wall of the wellbore. The insert extends in a direction so as to segment the paths of eddy current which would otherwise flow in the annular space. In a preferred embodiment, the logging tool includes a nuclear magnetic resonance apparatus having a longitudinal dipole antenna. The insulating inserts extend along the longitudinal axis of the tool so as to segment eddy current paths perpendicular to the longitudinal axis of the tool.