260 results about "Annihilation" patented technology

A combined PET/MRI scanner generally includes a magnet for producing a magnetic field suitable for magnetic resonance imaging, a radiofrequency (RF) coil disposed within the magnetic field produced by the magnet and a ring tomograph disposed within the magnetic field produced by the magnet. The ring tomograph includes a scintillator layer for outputting at least one photon in response to an annihilation event, a detection array coupled to the scintillator layer for detecting the at least one photon outputted by the scintillator layer and for outputting a detection signal in response to the detected photon and a front-end electronic array coupled to the detection array for receiving the detection signal, wherein the front-end array has a preamplifier and a shaper network for conditioning the detection signal.

A method for acquiring PET images with reduced time coincidence window limits includes obtaining a preliminary image of a patient within a radiation field of view (FOV), determining the spatial location of the patient within the FOV based on the preliminary image, calculating a different time coincidence window based on the spatial location of the patient for each possible pair of oppositely disposed detectors, scanning the patient with a PET scanning system to detect a pair of gamma photons produced by an annihilation event, determining whether the detection of the pair of gamma photons occurs within the time coincidence window, accepting the detected event only if the detection of the gamma photons occurs within the time coincidence window, calculating the spatial location of accepted annihilation event, and adding the calculated spatial location of the annihilation event to a stored distribution of calculated annihilation event spatial locations representing the distribution of radioactivity in the patient.

Method and apparatus for real-time tracking of a target in a human body. In one embodiment of the invention, positron emission marker may be implanted into a target, the positron emission marker having a low activity positron isotope. In one embodiment, annihilation gamma rays associated with the low activity positron isotope may be detected using a plurality of position-sensitive detectors. In another embodiment, the target may be tracked in real-time based on a position of the positron emission marker.

The present invention concerns very fast scintillator materials comprising lutetium iodide doped with Cerium (Lu_1-xI₃:Ce_x; LuI₃:Ce). The LuI₃ scintillator material has surprisingly good characteristics including high light output, high gamma ray stopping efficiency, fast response, low cost, good proportionality, and minimal afterglow that the material is useful for gamma ray spectroscopy, medical imaging, nuclear and high energy physics research, diffraction, non-destructive testing, nuclear treaty verification and safeguards, and geological exploration. The timing resolution of the scintillators of the present invention provide compositions capable of resolving the position of an annihilation event within a portion of a human body cross-section.

Systems and methods for using antiprotons for terminating unwanted or undesirable cells which can be used in the treatment of conditions caused by the existence and/or proliferation of such undesirable cells. Such conditions include cardiovascular ailments, Parkinson's disease, wet macular degeneration, endocrine disorders, dermatological ailments, and cancer. Because of the unique nature of antiprotons and their annihilation characteristics, the preferred antiproton delivery device (1010, 1015, 1030) embodiments further incorporate detector arrays (1050a), capable of detecting characteristic emissions in the course of treatment.

An electrode structure comprises a semiconductor junction comprising an n-type semiconductor layer and a p-type semiconductor layer; a hole exnihilation layer on the p-type semiconductor layer; and a transparent electrode layer on the hole exnihilation layer. The electrode structure further comprises a conductive layer between the hole exnihilation layer and the transparent electrode layer. In the electrode structure, one or more of the hole exnihilation layer, the conductive layer and the transparent electrode layer may be formed by an atomic layer deposition. In the electrode structure, a transparent electrode formed of a degenerated n-type oxide semiconductor does not come in direct contact with a p-type semiconductor, and thus, annihilation or recombination of holes generated in the p-type semiconductor can be reduced, which increases the carrier generation efficiency. Further, the electric conductivity of the transparent electrode is increased by the conductive layer, which improves electrical characteristics of a device.

Methods and systems for imaging a patient are provided. The method includes determining a location of a volume of interest within the patient and acquiring a plurality of frames of emission data, at least one frame including the volume of interest. The method further includes determining a time-of-flight (TOF) information of at least a portion of the annihilations detected along a line of response between corresponding coincidence detectors and generating an image of the patient from the emission data using the determined TOF information.

This invention provides methods for fabricating substantially continuous layers of group III nitride semiconductor materials having low defect densities. The methods include epitaxial growth of nucleation layers on a base substrate, thermally treatment of said nucleation layer and epitaxial growth of a discontinuous masking layer. The methods outlined promote defect reduction through masking, annihilation and coalescence, therefore producing semiconductor structures with low defect densities. The invention can be applied to a wide range of semiconductor materials, both elemental semiconductors, e.g., combinations of Si (silicon) with strained Si (sSi) and/or Ge (germanium), and compound semiconductors, e.g., group II-VI and group III-V compound semiconductor materials.

Non-destructive testing apparatus may comprise a photon source and a source material that emits positrons in response to bombardment of the source material with photons. The source material is positionable adjacent the photon source and a specimen so that when the source material is positioned adjacent the photon source it is exposed to photons produced thereby. When the source material is positioned adjacent the specimen, the specimen is exposed to at least some of the positrons emitted by the source material. A detector system positioned adjacent the specimen detects annihilation gamma rays emitted by the specimen. Another embodiment comprises a neutron source and a source material that emits positrons in response to neutron bombardment.

A QRD processor for computing input signals in a receiver for wireless communication relies upon a combination of multi-dimensional Givens Rotations, Householder Reflections and conventional two-dimensional (2D) Givens Rotations, for computing the QRD of matrices. The proposed technique integrates the benefits of multi-dimensional annihilation capability of Householder reflections plus the low-complexity nature of the conventional 2D Givens rotations. Such integration increases throughput and reduces the hardware complexity, by first decreasing the number of rotation operations required and then by enabling their parallel execution. A pipelined architecture is presented (290) that uses un-rolled pipelined CORDIC processors (245a to 245d) iteratively to improve throughput and resource utilization, while reducing the gate count.

The present invention concerns very fast scintillator materials comprising lutetium iodide doped with Cerium (Lu_1-xI₃:Ce_x; LuI₃:Ce). The LuI₃ scintillator material has surprisingly good characteristics including high light output, high gamma-ray stopping efficiency, fast response, low cost, good proportionality, and minimal afterglow that the material is useful for gamma-ray spectroscopy, medical imaging, nuclear and high energy physics research, diffraction, non-destructive testing, nuclear treaty verification and safeguards, and geological exploration. The timing resolution of the scintillators of the present invention provide compositions capable of resolving the position of an annihilation event within a portion of a human body cross-section.

A device is provided that can capture and store electrically neutral excited species of antimatter or exotic matter (a mixture of antimatter and ordinary matter), in particular, excited positronium (Ps*). The antimatter trap comprises a three-dimensional or two-dimensional photonic bandgap (PBG) structure containing at least one cavity therein. The species are stored in the cavity or in an array of cavities. The PBG structure blocks premature annihilation of the excited species by preventing decays to the ground state and by blocking the pickoff process. A Bose-Einstein Condensate form of Ps* can be used to increase the storage density. The long lifetime and high storage density achievable in this device offer utility in several fields, including medicine, materials testing, rocket motors, high power/high energy density storage, gamma-ray lasers, and as an ignition device for initiating nuclear fusion reactions in power plant reactors or hybrid rocket propulsion systems.

In beam monitoring for detecting annihilation radiations produced by radiation irradiation in radiation therapy for cancer which is performed by irradiating the affected area by X-rays, gamma rays, or particle beams, a detector-shift type combined radiation therapy/PET apparatus is provided with an open PET device that includes a plurality of shiftable multi-ring detector rings; and a radiation irradiation device that is capable of irradiation with a radiation beam through between the detector rings. The apparatus changes the positions of the detector rings, performs irradiation with the radiation beam through between the detector rings, and then performs radiation measurement.

An imaging device, or a PET device, opposed gamma camera type PET device, or open PET device in particular, that is combined with a radiation therapy device, in which detectors are rotated to reduce incidence of nuclear fragments on the detectors. For example, in an opposed gamma camera type PET device, beam irradiation and detector rotation can be synchronized to prevent the detectors from interfering with the treatment beam and reduce the incidence of nuclear fragments on the detectors. This makes it possible to reduce the incidence of nuclear fragments on the detectors without interfering with a treatment beam, thereby enabling measurement of annihilation radiations and three-dimensional imaging of the irradiation field immediately after irradiation or during irradiation.

The method calculates a scatter estimate for annihilation photons in a subject having a distribution of attenuation. The method can be used for scatter correction of detection data from a positron emission tomographic scanner. The method uses the following steps: —select a first scatter point S₁ and a second scatter point S₂, —determine a first scatter probability for scattering of a photon at scatter point S₁ and a second scatter probability for scattering of a photon at scatter point S₂, —determine an integral of the attenuation over a line connecting S₁ and S₂, —multiply the integral and the scatter probabilities and use the product in the calculation of the scatter estimate.

Provided are new methods for enhancing the selection of true (T) annihilation events relative to the inclusion of true scattered (TS) and random (R) annihilation events in PET tomographs and thereby improving the sensitivity and/or resolution of PET scanners. The methods include reconstruction of Compton scattering interactions in the γ-ray detectors for determining the angles of incidence of the γ-rays received at the detectors and may utilize γ-ray polarization effects and electron recoil data associated with positron annihilation and Compton scattering. The use of the γ-ray polarization effects provides an improved ability for selecting data corresponding to T events while simultaneously suppressing data corresponding to TS and R events during PET applications.

A proton held aligned in a sufficiently strong magnetic field maintaining the low energy state for the body can be decayed with cyclic 2 Hz radio waves to provide one of three types of energy: fusion, gravity waves and anti-gravity, and particle-antiparticle annihilation. New elements may also be formed as a result of the ability to rapidly decay protons at room temperature.

The invention discloses a fused ring compound, which has a structure shown as a formula (I) or a formula (II). The effective conjugation of aromatic rings and heterocyclic rings is controlled in the fused ring compound; the hole performance is improved; meanwhile, the electronic transmission performance is favorably balanced; the compound has high triplet state energy level and glass transition temperature; material molecules cannot easily crystallize; when the fused ring compound is used as a luminescent layer host material, the efficient transfer of energy to guest materials can be guaranteed. The substituent group of the fused ring compound is regulated, so that the electron and hole transmission performance is further improved; the singlet state and triplet state energy level difference is reduced; the compound region of carriers is expanded; the triplet state exciton annihilation is prevented. The invention also discloses an organic electroluminescence device; at least one function layer contains the fused ring compound; the fused ring compound is used as the host material of the luminescent layer and is matched with the adjacent carrier transmission layer energy level; the luminous efficiency of the device is improved; meanwhile, the driving voltage of the device is reduced.

The invention discloses article detection equipment, comprising an X-ray machine, an X-ray machine collimator, a transmission detector array and at least one scattering detector array. Each scattering detector array comprises a plurality of identical detection modules which are arranged into i rows and j lines, wherein an transmission section, transmitted by X-rays, of an article is divided into identical partitioned areas of i rows and xj lines, and the ixj detection modules of each scattering detector array correspond to the ixj partitioned areas of the transmission section of the article in a one-to-one manner, and are used for detecting electron-pair-effect annihilation photons and Compton scattering photons generated by the X-rays at the corresponding partitioned areas, and acquiring atomic number of each partitioned area according to the specific vale of the count of the detected electron-pair-effect annihilation photons to the count of the detected Compton scattering photons, so as to form a three-dimensional image of the article. In addition, the invention further provides a method for detecting the article by using the article detection equipment.