Abstract: An explosive and narcotics detection system detects the presence of trace particles of materials that are adhering to surfaces. In order to detect such particles, to the particles are first dislodged or released from the surface, then transported to the detection instrument, and then accumulated on or in a particle collection device. When the sample collecting system and the target surface are in relative motion across the line-of-sight greater than fifteen centimeters per second, non-contact sample collection may be accomplished using a vortex or vortex attractor particle collector together with a plurality of air or aerosol jets. A plurality of large diameter vortex collectors may obtain samples at relative line-of-sight velocities greater than five feet per second over a large surface area and for a complex-shaped surface.

Abstract: A radiation protection system for shielding medical personnel from a gamma ray source being used to provide brachytherapy to a patient is provided by disposing shielding material between the source of radiation and locations outside the radiation protection system in such a manner as to provide shielding for the primary radiation in directions from which radiation from the source may emerge, while providing the patient an open viewing area with a large field of view for the patient to view the locations outside the radiation protection system. The described system reduces the radiation exposure of staff in the treatment room, thereby permitting physicians and therapists to observe the patient without being exposed to excessive amounts of radiation. The opening in the radiation protection system around the head of the patient provides the ability for the patient to see his surroundings and to eliminate the anxiety resulting from the feeling of being closed in.

Abstract: Vapor concentrators are used to provide a higher concentration of trace target vapor than would normally be available in the environment. This is accomplished by allowing the trace target vapor to adsorb onto a concentrating surface and subsequently releasing the trace target vapor by heating the surface. An improved desorbing method is providing by a fast pulse of photons, which only heats the near surface region, rather than the entire mass of the substrate on which the concentrating surface resides. Since all of the trace target vapor is released in a short time interval, the vapor is less diluted by carrier gas than would occur during the slower temperature ramp that results when the entire substrate mass is heated. A more highly concentrated target vapor is produced with less input of energy.

Abstract: The presence of trace molecules in air is often determined using high sensitivity gas sensing instruments, such as an ion mobility spectrometer. Such devices are commonly utilized in the fields of explosives detection, identification of narcotics, and in applications characterized by the presence of very low airborne concentrations of organic molecules of special interest. The sensitivity of such instruments is dependent on the concentration of target gas in the sample. The sampling efficiency can be greatly improved when the target object is warmed, even by only a few degrees. A directed emission of photons in the range between infrared and ultraviolet light can be used to significantly enhance vapor emission.

Abstract: Intravascular devices having a radiopaque layer thereon for visualization are provided. The devices further includes a capping layer on the radiopaque layer to prevent exposure of the radiopaque material to surrounding tissues. A method of coating the device is also provided. The method includes using an unbalanced magnetic field magnetron to generate, from a source, metal atoms for coating and bombarding ions for compressing deposited metal atoms to the surface of the device.

Abstract: The presence of trace molecules in air may be determined using an ion mobility spectrometer. Such devices may be used in the fields of explosives detection, identification of narcotics, and in applications characterized by the presence of very low airborne concentrations of organic molecules of special interest. The sensitivity of such instruments may depend upon on the method of gas sampling utilized. A virtual wall gas sampling system can greatly improve the sampling efficiency, particularly when the sampling needs to be performed at a distance from the air intake and large volumes need to be sampled. The virtual wall gas sampling system consists of an intake gas flow and a separate group of one or more sheet-like gas flows, which may be either mutually deflected to move with a circular motion or may be formed into a cylindrical bounding surface.

Abstract: The presence of trace molecules in air is often determined using a well-known device called an ion mobility spectrometer. Such devices are commonly utilized in the fields of explosives detection, identification of narcotics, and in applications characterized by the presence of very low airborne concentrations of organic molecules of special interest. The sensitivity of such instruments is dependent on the method of gas sampling utilized. The vortex sampling nozzle consists of an intake gas flow and a separate coaxial heated, emitted gas flow that is deflected to move with a circular motion. A heated vortex sampling nozzle can greatly improve the sampling efficiency for low volatility target molecules, particularly when the sampling needs to be performed at a distance from the air intake and the vapor pressure of the target molecules is very low.

Abstract: The presence of trace molecules in air may be determined using an ion mobility spectrometer. Such devices may be used in the fields of explosives detection, identification of narcotics, and in applications characterized by the presence of very low airborne concentrations of organic molecules of special interest. The sensitivity of such instruments is dependent on the method of gas sampling utilized. A cyclone sampling nozzle can greatly improve the sampling efficiency, particularly when the sampling needs to be performed at a distance from the air intake. The cyclone sampling nozzle consists of an intake gas flow and a separate coaxial emitted gas flow which is deflected to move with a circular motion.

Abstract: An explosive detection system detects the presence of trace molecules in air. The sensitivity of such instruments is dependent on the concentration of target gas in the sample. The sampling efficiency can be greatly improved when the target object is warmed, even by only a few degrees. A directed emission of photons, typically infrared or visible light, can be used to significantly enhance vapor emission. The sensitivity of such instruments is also dependent on the method of gas sampling utilized. A cyclone sampling nozzle can greatly improve the sampling efficiency, particularly when the sampling needs to be performed at a distance from the air intake.

Abstract: A system for brachytherapy is provided. The system includes an implantation device having a tubular member, a radioactive source within the member, and a socket at opposing ends of the tubular member. A plurality of implantation devices may be joined into an assembly by use of a spacer positioned within the sockets of adjoining devices. The device may be deployed at an implantation site by use of a delivery mechanism, such as needle. The presence of the tubular members and spacers minimizes movement of the radioactive source subsequent to deployment, so as not to alter dose distribution for subsequent irradiation.

Abstract: This application relates to devices and methods for locally delivering therapeutic radiation to tissue in the body of a patient. In certain embodiments, the subject devices are implanted into a cavity in the patient left by surgical removal of tumorous tissue or other diseased tissue, to deliver radiation to the tissue surrounding the cavity. In certain embodiments, the devices are elastic or can otherwise be shaped to conform to the shape of the cavity in the patient.

Abstract: The present invention comprises methods for producing semiconductor devices useful in high temperature applications. The invention is based on using silicon ion implantation to convert a portion of the p-type base layer of magnesium-doped GaN into n-type GaN. The boundary of the n-type GaN within the p-type layer then becomes an n-p diode junction which can function as the emitter-base junction. The present methods utilize ion implantation to convert a portion of the p-type layer to n-type thereby forming an n-p junction having desirable diode characteristics. The invention also includes BJT and HBT devices incorporating the present implanted n-p diode junctions.

Abstract: A device for treating an occlusion or constriction, such as a stenosis in a blood vessel or other conduit within the body, as well as for treating a tumor or cancerous area occurring around a conduit or duct in the body is provided. The device includes an insert having a non-radioactive precursor, and a capsule encapsulating the insert. The precursor, containing tungsten which is substantially enriched in tungsten-180, can be activated to emit X-ray radiation and delivered to the treatment site to treat the stenosis or cancerous area. Upon activation by exposure to neutron flux, tungsten-180 is transmuted to contain an amount of X-ray-emitting tungsten-181 sufficient for treatment. The tungsten can also act as an X-ray-opaque marker to facilitate external visualization of capsule after delivery to the treatment site.

Abstract: A dental article coated with a friction-reducing coating and methods for coating dental articles are disclosed. In one embodiment, the dental device first is coated with an adhesion layer, followed by application of a friction-reducing coating. The friction-reducing coating is selected to create a hard, inert, friction-reducing layer on the device. The presence of the continuous outer coating of on the device reduces adhesive wear and friction on the device, and significantly improves its frictional properties.

Abstract: The present invention provides methods and devices which use a palladium source enriched in Pd-102 and depleted in Pd-108 and Pd-110 to coat the body of a medical device. Whereas prior devices, which include palladium throughout the volume of the body, require the use of highly enriched palladium sources to counteract the effect of absorption of radiation by palladium and other metals in the body, devices wherein palladium is located primarily on the surface of the body more efficiently deliver therapeutic radiation to the target tissue, and thus can employ less highly enriched palladium sources. Such palladium sources are significantly less expensive than highly enriched sources, thereby greatly reducing the cost of devices and methods which use such a coating of palladium.

Abstract: An implantable medical device according to the present invention comprises a body, such as a stent or a wire, and an isotope having a high neutron activation cross-section, such as 168Yb or 124Xe, ion-implanted onto the surface of the body. The use of isotopes having high neutron activation cross-sections allows a wider choice of substrates to be employed, including stainless steel, nickel, titanium, and alloys including these metals, because the time required for neutron activation of the device is reduced. A coating of high-density material may be incorporated to serve several useful purposes, including containment of undesirable beta particles from long-lived radioactive species, creation of a biologically inert surface, and enhancement of x-ray radiopacity to improve the visibility of an implanted medical device. The implantable medical devices of the present invention also comprise radioactive medical devices which include radioisotopes such as 169Yb and 125I.

Abstract: Past techniques utilized wet chemistry to produce a carrier free radioisotope for a seed implant. However, by using the technique of ion implantation, it is possible to physically separate the precursor isotope by magnetic means and further, to physically direct a beam of these isotopically pure atoms and to embed them into a suitable carrier body. Thus, formation of the seed implant may be accomplished using dry techniques, that is, no liquid chemistry. The systems and methods disclosed herein are designed to produce a beam of a single stable isotope using an ion implanter and to further implant this single stable isotope below the surface of a carrier body. After neutron activation, these single stable isotopes will produce the isotopes iodine-125, palladium-103, cesium-131, or ytterbium embedded within the carrier body. Optionally, the carrier body may be encapsulated prior to activating the precursor isotope embedded in the carrier body.

Abstract: An implantable medical device according to the present invention comprises a body, such as a stent or a wire, having a radioisotope or non-radioactive precursor isotope associated with the body. The isotope preferably is disposed on the body using an efficient deposition method, such as an effusion cell. The method reduces the waste of costly isotopes and reduces the buildup of hazardous material in the apparatus. A metal layer may be deposited simultaneously with or subsequent to deposition of the isotope to encapsulate the radioactive isotope.

Abstract: An implantable medical device according to the systems and methods described herein may include a metal body or stent that does not contain significant quantities of iron or chromium and that is initially formed from a non-radioactive structural material. A non-radioactive activatable additive (the precursor isotope) may be added into or onto the body of the medical device. Neutron activation of the body of the medical device with the incorporated non-radioactive isotope may then be accomplished, and, if the metal body of the medical device contains a significant quantity of nickel, a coating of a high-density material may be applied over the radioactive body of the medical device. In an alternate embodiment, a coating of certain types of high-density material may be applied prior to neutron activation.

Abstract: The present invention relates to a novel planar technology approach utilizing ion implantation to improve the fabrication procedure for manufacturing nitride light-emitting and laser diodes. The simplified processing significantly reduces the costs of manufacturing these devices and allows flip-chip bonding to be used for efficient heat removal, yielding much brighter LEDs and more powerful lasers.