Abstract: A system for analyzing bone conditions, particularly (but not solely) for diagnosing osteoporosis and periodontal bone disease in humans. An ultrasonic signal (generally a pulse) having components in a range from about 50 kHz to about 600 kHz (and preferably to about 3 MHz) is launched transdermally into a bony member such as the patella, and received after passage therethrough. Scattering of the incident wave energy in the bony member, and absorption and phase delay in the tissue, cause the transmission to vary in both amplitude and phase as a function of frequency. A multivariable analysis is performed on a plurality of variables characterizing the signals transmitted through, reflected from or scattered by the bony member and soft tissue. The measured parameter values characterize the bone architecture and are compared with the statistics for one or more groups having known bone condition, to yield a probabilistic diagnosis of bone condition.

Abstract: A system for analyzing bone conditions, particularly (but not solely) for diagnosing osteoporosis and periodontal bone disease in humans. An ultrasonic signal (generally a pulse) having at least two components of distinguishable waveshape or frequency content in a range from about 100 kHz to about 3 MHz is launched transdermally into the patient, through a bony member such as the patella, and received at the other side. The transmission through the bony member and surrounding soft tissue varies in both amplitude and phase as a function of frequency, and the velocity of transmission varies between the bony member and the soft tissue. A variety of techniques are employed for analyzing the transmission of the ultrasonic signal to assess bone condition. These include at least: comparing the transit times through the bony member of energy in a first frequency range and energy in a second frequency; evaluating the transfer function through the bony member (i.e.

Abstract: Optical strain gauge employing evanescent field coupling between optical fibers. Optical fibers are spaced apart for evanescent field coupling on a structure whose strain is to be measured. Light is introduced into an input fiber which couples into an output fiber depending on the separation between the fibers. Light coupled into the output fiber is detected to generate an output signal indicative of the separation between fibers and hence strain in the supporting structure. In one embodiment, apparatus is provided to measure strain at a plurality of locations with but a single input and a single output fiber. In this embodiment, the input fiber and the output fiber are separated for evanescent coupling at a plurality of locations. The lengths of the input and output fibers between the locations where strain is measured are unequal to produce light propagation time delays.

Abstract: A system for establishing, in vivo, the strength of bone in a live being such as, for example, a horse. The system permits determination of the speed of travel of sound through the bone and the strength of the bone is assessed on the basis of said speed of travel.

Abstract: A method of coating a portion of the walls and effecting a degree of penetration into a bone with a coating material to produce a modified bone surface, the method comprising: introducing the coating material onto the bone surface in an initial physical state; applying pressure to the coating material to force the material into the structure of the bone; and maintaining pressure on the coating material until it reaches a desired final physical state.

Abstract: An optical transistor wherein an optical medium receives a pump signal and produces therefrom an internal optical signal, an optical control signal being directed into the optical medium to perturb the optical properties of the medium and to thereby modify the amplitude of the internal optical signal. A plurality of optical transistors are shown in various logic configurations.

Abstract: Solid-state waveguide structures are disclosed to detect and/or encode very fast (picosecond) optical signals. The waveguides are appropriately configured to cause very fast signals to interact with interrogation or erasure pulses by a two photon absorption mechanism. The coincidence of the pulses in particular regions causes erasure and/or changes in the waveguide conductivity which can be measured conventionally by parallel circuitry.

Abstract: A method for establishing, in vivo, the strength of bone in a live being such as, for example, a horse. The method permits determination of the speed of travel of sound through the bone and the strength of the bone is assessed on the basis of said speed of travel.

Abstract: A pre-coated body implant, such as, for example, a hip prosthesis, in which that portion of the implant that attaches to or is inserted into a skeletal member of the body has a pre-coating of a material (e.g., an acrylic material) covering all or most of said portion and bonded thereto.

Abstract: A method of assessing performance potential of a quadruped by determining the timing of successive making and breaking of ground contact by the legs during the stride and the swing time of a leg of the quadruped while in a high-speed gait. Overlap time of the legs, that is, the time that more than one leg is on the ground at one time, as a function of the forward speed of the quadruped and the time required to complete the stride are derived. The total airborne time is determined and related to the stance, swing, and overlap of the stride time. Performance is assessed in terms of swing time, stance time, overlap time, airborne time and combinations thereof. A method is disclosed of relating measurements of the gait taken at an arbitrary speed to a standard reference speed for purposes of comparing different individuals.

Abstract: Luminescent semiconductor device having a wide-gap semiconductor material substrate (e.g., ZnS), a thin (.ltorsim.100A thick) alkali halide insulating layer (e.g., NaI, KI, LiI) in the substrate and a metal layer on the insulating layer such that the insulating layer is sandwiched between the substrate and the metal layer. The device emits light in the blue and in the green regions of the electromagnetic spectrum.

Abstract: A system operable to measure the time varying forces transmitted by a body and to combine the forces transmitted by different parts of the body. The system can be employed to measure physiological forces associated with motion of the body such as the gait of humans or animals. It can also be employed to measure forces internally generated by the body at rest such as ballistocardiographic and posture control forces. The posture control forces can be used as a measure of lameness. The Fourier transform of the force ballistocardiogram and posture control forces are found to contain information related to physiological condition. In some configurations the system employs ceramic capacitors as piezoelectric force transducers in a special circuit. The use of ceramic capacitors as pyroelectric bolometers is also discussed.

Abstract: Apparatus for altering (i.e., deactivating or activating) the biological or chemical activity of macromolecular species that employs laser beam radiation at a frequency that excites vibrational and rotational states of the irradiated species and at an intensity sufficient to activate the species (but below the denaturation level) or to a level such that the weak bonds -- e.g., hydrogen bonds -- that determine the spatial character, and hence the biological activity of macromolecules are irreversibly broken to such extent that the macromolecule loses its original form (the process of denaturation) and assumes an inactive (denatured) configuration. In the case of absorbing materials, pulses of energy from the beam, which are obtained by interrupting a c.w. beam, using a pulsed laser, or as a Q-switched configuration, are used. In a broad sense, the invention is primarily directed to the breakdown of large molecules either into varieties with different spatial characteristics or into smaller molecular units.

Abstract: A spark plug wherein corona discharge is employed to create a long arc and to determine, in part, the path of the arc, electrodes of the spark plug being shaped, oriented and positioned to create an arc of desired length, orientation and at a desired location as well as to effect electromagnetic interaction between electric current in the arc and the current in at least one of the electrodes to provide a force on the arc which acts in consort with the electrode shapes, positions and orientations to control its spatial behavior, the electrode configuration being further selected so that ionized species in the flame of ignited fuel are subjected to a high electric field over a substantial volume.

Abstract: A discharge device for igniting a fuel-air mixture whereby fuel droplets in the mixture are electrically charged and, under the influence of an electric field, caused to congregate at a region thereby concentrating the mixture at said region, means being provided to create an arc at said region. A device of more general use is also disclosed.

Abstract: A spark plug wherein corona discharge is employed to create a long arc and to determine, in part, the path of the arc, electrodes of the spark plug being shaped, oriented and positioned to create an arc of desired length and at a desired location as well as to effect electromagnetic interaction between electric current in the arc and the electrodes to provide a force on the arc which acts to control its spatial behavior. The spark plug includes means to enhance the electromagnetic interaction.

Abstract: A method of altering (i.e., deactivating or activating) the biological activity of macromolecular species that employs laser beam radiation at a frequency that excites vibrational and rotational states of the irradiated species and at an intensity sufficient to activate the species (but below the denaturation level) or to a level such that the weak bonds-- e.g., hydrogen bonds--that determine the spatial character, and hence the biological activity of macromolecules are irreversibly broken to such extent that the macromolecule loses its original form (the process of denaturation) and assumes an inactive (denatured) configuration. The latter is a sterilization or inactivating process and for such sterilization the macromolecular species may be disposed on a highly reflecting surface, such as a metal, which reflects the beam and is capable of amplifying the destructive characteristic, or upon absorbing surfaces, such as plastics, cloth or paper which ordinarily would be destroyed by the beam.

Abstract: A system for establishing, in vivo, the strength of bone in a live being such as, for example, a horse. The system permits determination of the speed of travel of sound through the bone and the strength of the bone is assessed on the basis of said speed of travel.The questions raised in reexamination request No. 90/000,815, filed 07/22/85, have been considered and the results thereof are reflected in this reissue patent which constitutes the reexamination certificate required by 35 U.S.C. 307 as provided in 37 CFR 1.570(e).