Abstract: An adjustable resistance upper body exerciser includes a generally arcuate belt (2) encircling the waist of a user and having a generally flat, rigid posterior central portion 3 and flexible anterior portions (4, 4a) including buckling means (5). A flexible inelastic cord (7) having a length and left and right ends (8, 8a) passes through an elongated guide means (12) attached to the belt, slidably retaining a central portion of the length the cord and leaving the right and left ends of the cord extending in the anterior direction. A snubber (15) is attached to the rigid posterior portion of the belt, contacting the slidable cord and applying an adjustable friction load to the slidably retained cord. A pair of handles (18, 18a) are attached to left and right ends of the cord, whereby a user wearing the belt encircling the waist may alternately pull said left and right handles with a tension force generally proportional to the friction load applied to the cord by the snubber.

Abstract: A plastic light conduit of cross-linked polymer material having good light transmitting characteristics, without voids or noticeable bubbles, is disclosed. Also disclosed is a method of manufacture and an apparatus, involving progressive heating of reactive monomer mixture in a tube which is submerged in a progressive reactor utilizing cold oil to maintain a cold, non-reacting zone, and hot water to create a hot zone that causes reaction, while simultaneously carrying away the excess exothermic heat of reaction.

Abstract: The present invention is directed to a heat shrink clad core optical conduit and to an optical conduit having either a thermoplastic, thermoset or liquid, light transmitting core surrounded by, preferably a fluoropolymer cladding which is in turn surrounded by a tight-fitting, finish polymer jacket which may be either transparent or translucent, and is preferably made of a polyvinyl chloride, polycarbonate, acrylic or silicone material. Numerous fillers and inserts may be used in the finish jacket polymer and the finish jacket polymer may be formed into various shapes. Bondable jacket materials may be used. The preferred method of forming the manufacturing jacket around a heat shrinkable fluoropolymer cladding is by extruding a low extrusion temperature polymer over a heat shrink clad in its expanded form into which an increased interior pressure is maintained to prevent shrinkage during the extrusion process.

Abstract: A single-layer blood separation medium for separating erythrocytes from whole blood and made of a composite including glass microfibers, cellulose fibers, and synthetic textile fibers, having enhanced tensile strength and lower absorptive capacity compared to binderless glass microfiber sheet. The mean bulk density of the glass microfiber component is less than 0.1 g/cm.sup.3, and is typicaly about 0.05 g/cm.sup.3.