Abstract: A catheter maps an electrical conduction pattern in an annular region of a heart. The catheter has a tubular shaft that has a pre-shaped curved distal section adjacent the distal end thereof, and at least one lumen extending between the distal end and the proximal end of the shaft, with a plurality of electrodes disposed on the distal section. A handle is attached to the proximal end of the shaft, with a steering mechanism provided at the handle for adjusting the curvature of the distal section, and a deflection mechanism provided at the handle for deflecting the distal section. The electrodes are positioned in a parallel plane separate from the shaft when the distal section is undeflected.

Abstract: A catheter maps an electrical conduction pattern in an annular region of a heart. The catheter has a tubular shaft that has a pre-shaped curved distal section adjacent the distal end thereof, and at least one lumen extending between the distal end and the proximal end of the shaft, with a plurality of electrodes disposed on the distal section. A handle is attached to the proximal end of the shaft, with a steering mechanism provided at the handle for adjusting the curvature of the distal section, and a deflection mechanism provided at the handle for deflecting the distal section. The electrodes are positioned in a parallel plane separate from the shaft when the distal section is undeflected.

Abstract: A photonic crystal fiber (1) has a fiber body including a core (2) and a cladding (3) which is provided to surround the core (2) and having a plurality of microscopic holes (3a) extending along the core (2). In the photonic crystal fiber (1), the openings of the plurality of microscopic holes (3a) of the cladding (3) located at an end of the fiber body are closed with blocking element (5) having a lower refractive index than the core (2), and thereafter the fiber end face is polished.

Abstract: A foamable composition containing a base polymer containing a polyethylene mixture of a low density-polyethylene having a density of 0.91-0.925 g/cm3 and a high density polyethylene having a density of 0.94-0.97 g/cm3, and a fluororesin powder and/or a boron nitride powder as a nucleator, wherein the high density polyethylene has an swelling ratio smaller than that of the low density polyethylene and a melt flow rate greater than that of the low density polyethylene, and is contained in a proportion of not less than 50 percent by weight of the polyethylene mixture, and the base polymer has a shear viscosity (temperature:170° C., shear rate:1216 sec−1) of not more than 3150 poise, and a coaxial insulating cable having an electrically insulating layer formed of a foam having an expansion ratio of not less than 70% and obtained by foaming the above foamable composition are provided.

Abstract: An insulating material for coaxial cables, made at least in part with a polyolefin resin capable of heat-melt extrusion and a fluororesin powder as a nucleator, which material being capable of foam extrusion in the presence of a foaming agent; a coaxial cable made at least in part with a foam insulating layer prepared from the insulating material; and a method for producing a coaxial cable, by extruding, on a conductor, the insulating material to form a foam insulating layer. The insulating material for coaxial cables of the present invention containing a fluororesin powder such as PTFE as a nucleator provides a foamed article having fine and uniform cells, and a high expansion ratio. Such foamed article is superior in electric properties, and the coaxial cable having such insulating layer is superior in attenuation property. The material of the invention can obviate drying of the insulating layer, which contributes to an improved production efficiency of the coaxial cable and reduced production cost.

Abstract: A nucleator for foaming comprising a fluororesin powder comprising particles having a particle size of 0.1-0.5 .mu.m in a proportion of at least 50% by number and containing particles having a particle size of not less than 5 .mu.m in a proportion of not more than 40% by number, a foamable composition comprising this nucleator and an organic polymer, a foam made therefrom, and a production method of the foam. The nucleator of the present invention can produce a foam made from an organic polymer improved in expansion ratio, fineness of the cells, uniformity of foaming and the like by the use of an extremely small amount thereof. It is preferably used for forming an insulating foam layer of a high frequency coaxial cable.

Abstract: A foamable organic composition comprising a compound foamable to 50% or more comprising an organic polymer and a chemical foaming agent, and, as a physical foaming agent, at least one member selected from the group consisting of rare gases and carbon dioxide; and a method for producing a foamed article having a high expansion ratio by using said composition. According to the present invention, a foamed article having a uniform and fine foam structure and a high expansion ratio of not less than 75% (which is as high as when freon gas is used) can be obtained without causing environmental problems such as depletion of the ozon layer. When applied, in particular, to a foamed layer for an insulated conductor, such as foam-insulated electric wire which is required to have high performance insulation and is occasionally installed under severe conditions, the composition of the present invention advantageously provides an insulated conductor with no potential buckling.