Abstract: An improved inductive plethysmography sensor involving a conductor having alternating active and inactive segments. The active segments preferably have a narrow diamond shape which minimizes the possibility of artifact. Because of the conductor design, the sensors can be placed completely about the chest and abdomen with any overlap arranged so that active segments overlap inactive segments.

Abstract: The self-inductance sensor disclosed includes a band of distensible material, and a strap of nondistensible material which form in combination a closed loop which circumscribes the object. A conductor is secured to the band of distensible material. The conductor includes two portions each extending from one end of the band to the other and having an irregular repetitive configuration. The conductor portions are symmetrically juxtaposed to one another to form a series of substantially enclosed areas which change shape as the band is distended. The self-inductance of the conductor is measured to indicate the relative extension of the band and thus the change in circumference of the object.

Abstract: An improvement is made in 2-site immunoradiometric assay wherein a single labelled antibody can be used to assay many different antigens.

Abstract: An apparatus for conducting chemical assays features a coiled soft plastic tube as a reaction chamber. Along the length of the plastic tubing is a slit therein through which a needle-like member of a travelling dispenser injects samples to be analyzed. The injected samples may react with a reactant previously deposited in the interior of the plastic tube. The apparatus is applicable to carrying out radioimmunoassays.