Abstract: A system for detecting wear debris particulate from a medical implant within the body of a living animal is provided. The system includes an acoustic transmitter for transmitting acoustic energy from outside the body to a soft tissue region proximate the medical implant containing wear debris particles; an acoustic receiver located outside the body to detect resultant acoustic energy generated by the wear debris particles and produce a received signal indicative thereof; a processor for processing the received signal to evaluate at least one parameter associated with the wear debris particles; and an output for indicating the at least one parameter.

Abstract: An implant device which includes a structure implantable within a living animal and a sensor included as part of the structure. The sensor is operatively configured to detect accretion of biological material on the sensor by producing an output which varies as a function of the accretion of biological material on the sensor. A communication element is further included as part of the structure and is operatively coupled to the output of the sensor. The communication element is configured to communicate information based on the output of the sensor wirelessly to a remote element located outside the living animal.

Abstract: An analyzer apparatus and method is provided for analyzing restenosis associated with a stent implanted within a living body. The apparatus includes an input for receiving ultrasonic data from an ultrasonic imaging apparatus; digital memory for storing the ultrasonic data at least temporarily; a processor for analyzing the ultrasonic data, the processor being configured to analyze the data in accordance with at least one predefined criteria to diagnose a degree of restenosis experienced by the stent; and an output for outputting information indicative of the diagnosis.

Abstract: An implant device is provided which is responsive to an external interrogation circuit. The implant device includes a structure implantable within a living animal and operatively configured to carry out or assist in carrying out a function within the living animal. The device further includes an electrically passive sensing circuit integral with the structure for sensing a parameter associated with the function. In particular, the sensing circuit includes an inductive element wherein the sensing circuit has a frequency dependent variable impedance loading effect on the interrogation circuit in response to an interrogation signal provided by the exciter/interrogator element, the impedance loading effect varying in relation to the sensed parameter.

Abstract: A device and system for remotely interrogating a diagnostic implant device utilizes acoustic energy to power and/or interrogate the device. Acoustic energy is utilized to excite the device from outside the body of a patient. By analyzing the response of the device to such excitation, it is possible to ascertain the condition of the device. Additionally, acoustic energy may be used to provide operating power to the device.

Abstract: An implant device which includes a structure implantable within a living animal and a sensor included as part of the structure. The sensor is operatively configured to detect accretion of biological material on the sensor by producing an output which varies as a function of the accretion of biological material on the sensor. A communication element is further included as part of the structure and is operatively coupled to the output of the sensor. The communication element is configured to communicate information based on the output of the sensor wirelessly to a remote element located outside the living animal.

Abstract: A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, a useful powder is disclosed that has a two-tier distribution in which substantially no primary particles have an average diameter greater than 180 .mu.m, provided further that the number average ratio of particles smaller than 53 .mu.m is greater than 80%, the remaining larger particles being in the size range from 53 .mu.m to 180 .mu.m. A powder with slow recrystallization rates, as evidenced by non-overlapping endothermic and exothermic peaks in their differential scanning calorimetry characteristics for scan rates of on the order of 10.degree. C. to 20.degree. C.

Abstract: Ternary alloys of PVC/CPVC/alloying polymers are disclosed which make use of the unexpected results of interactions between alloying polymers and CPVC and PVC, interactions which result in higher heat distortion temperatures than predictable by linear addition of the properties of the binary blends of PVC/CPVC and PVC/alloying polymer systems. This effect allows replacement of substantial amounts of alloying polymer with a predetermined amount of CPVC without changing substantially HDT or melt viscosity. Such effects allow the use of these ternary alloys in place of binary PVC/alloying polymer systems in injection molding and extrusion applications.

Abstract: A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering (SLS) machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, the powder has a two-tier distribution in which substantially no primary particles has an average diameter greater than 180.mu.m, provided further that the number average ratio of particles smaller than 53.mu.m is greater than 80%, the remaining larger particles being in the size range from 53.mu.m to 180.mu.m. When the powder is a semicrystalline synthetic resin having a number average molecular weight in the range from about 30,000 to 500,000; a molecular weight distribution M.sub.w /M.sub.

Abstract: This method teaches how to recover and reuse a powder of a thermally degradable material which is used in a selective laser sintering (SLS) process. To recycle such a laser-sinterable powder successfully in a SLS machine it is protected against degradation by cooling the hot bed while layer-upon-layer (layer-wise) of powder is being sintered, seriatim, to form successive slices fused together to form an article of arbitrary shape (part). The process requires maintaining the powder which has more than 80% of the number of particles <53 .mu.m as a quiescent bed which is nevertheless porous enough to permit flowing a cooling gas downwardly through the bed without disrupting its surface. Since each slice is formed at the surface, and the part, as it is formed, is supported in a well-insulated bed, the powder adjacent the slice is at a much higher temperature than powder in the rest of the bed, which, but for the cooling gas, would get overheated.

Abstract: Smoke retardant vinyl chloride and vinylidene chloride polymer compositions are obtained by including cobaltous oxide (CoO) in the composition.

Abstract: Smoke retardant vinyl chloride and vinylidene chloride polymer compositions are obtained by including therein a synergistic mixture of (A) at least one nickel compound selected from the group consisting of NiCO.sub.3, NiCrO.sub.4, NiI.sub.2, NiO, NiS, NiSO.sub.4, nickel acetylacetonate, nickel citrate and nickel formate and (B) at least one iron compound selected from the group consisting of Fe.sub.3 C, Fe.sub.2 (MoO.sub.4).sub.3, Fe.sub.2 O.sub.3, Fe.sub.3 O.sub.4, FeS, cyclopentadienyl iron dicarbonyl, ferric acetylacetonate, ferric hydroxy distearate, and ferrocene. Substantial smoke retardation is also obtained by including the above nickel compounds or iron compounds individually in the vinyl chloride or vinylidene chloride polymer compositions.

Abstract: Smoke retardant vinyl chloride and vinylidene chloride polymer compositions are obtained by including therein a synergistic mixture of (A) at least one nickel compound selected from the group consisting of NiCl.sub.2, NiCO.sub.3 NiMoO.sub.4, NiO, Ni.sub.2 O.sub.3, NiS, NiSO.sub.4, NiWO.sub.4, nickel citrate and nickel formate, and (B) at least one bismuth compound selected from the group consisting of BiBO.sub.3, Bi.sub.2 O.sub.3, Bi.sub.2 O.sub.2 CO.sub.3, and Bi.sub.2 S.sub.3. Substantial smoke retardation is also obtained by including the above nickel compounds or bismuth compounds individually or the following nickel compounds or bismuth compounds individually in the vinyl chloride or vinylidene chlorides polymer compositions: NiB.sub.2, NiCrO.sub.4, NiFe.sub.2 O.sub.4, NiI.sub.2, Ni.sub.3 (PO.sub.4).sub.2, Ni.sub.2 Si, NiSnO.sub.3, nickel acetylacetonate, BiI.sub.3, or BiPO.sub.4.3H.sub.2 O.

Abstract: Smoke retardant vinyl chloride and vinylidene chloride polymer compositions are obtained by including therein a synergistic mixture of (A) at least one nickel compound selected from the group consisting of NiCO.sub.3, NiCl.sub.2, NiO, NiS and nickel acetylacetonate and (B) at least one zinc compound selected from the group consisting of ZnCO.sub.3, ZnCrO.sub.4, ZnMoO.sub.4, Zn.sub.3 (PO.sub.4).sub.2, Zn.sub.2 SiO.sub.4, ZnSO.sub.4, ZnTiO.sub.3, Zn.sub.2 ZrO.sub.4, zinc ammonium sulfate, zinc borate, zinc acetylacetonate, zinc formate, zinc oxalate, and M.sub.2.sub.-2x Zn.sub.3.sub.+x [Fe(CN).sub.6 ].sub.2.yH.sub.2 O wherein M is an alkali metal, x is from 0 to 1, and y is from 0 to 4. Substantial smoke retardation is also obtained by including the above nickel compound or zinc compounds individually in the vinyl chloride or vinylidene chloride polymer compositions.

Abstract: Smoke retardant vinyl chloride and vinylidene chloride polymer compositions are obtained by including therein a synergistic mixture of (A) at least one nickel compound selected from the group consisting of NiCO.sub.3, NiCrO.sub.4, NiMoO.sub.4, NiO, NiSO.sub.4, NiSnO.sub.3 and nickel stearate and (B) at least one copper compound selected from the group consisting of CuI, CuO, CuSCN, and 2-aminothiophenol Cu(I). Substantial smoke retardation is also obtained by including the above nickel compounds or copper compounds individually in the vinyl chloride or vinylidene chloride polymer compositions.

Abstract: Smoke retardant vinyl chloride and vinylidene chloride polymer compositions are obtained by including therein a synergistic mixture of (A) at least one nickel compound selected from the group consisting of NiCO.sub.3 and nickel citrate and (B) at least one zinc compound selected from the group consisting of ZnO and ZnTiO.sub.3. Substantial smoke retardation is also obtained by including the above nickel compounds or zinc compounds individually in the vinyl chloride or vinylidene chloride polymer compositions, except for ZnO.