Abstract: The invention is directed towards structures for use with micro-formed membrane ultrasonic transducers, and methods for fabricating the structures. In one embodiment, the transducer includes a planar member having a piezoelectric material and spaced apart electrodes disposed on the planar member and coupled to the piezoelectric material for applying an electric field to the layer, and an acoustic backing member joined to the electrodes. In another embodiment, the transducer includes a planar member having a piezoelectric material that adjoins a semiconductor material, the semiconductor material having monolithically formed active circuits formed in the layer and coupled to the piezoelectric material. In still another embodiment, the transducer includes a planar member having a piezoelectric material, and an acoustic backing member having an adjoining layer of a semiconductor material having monolithically formed active circuits, the active circuits being coupled to the electrodes.

Abstract: In general, peer-to-peer techniques are described for providing secure communications using digital certificates assigned to secure communication servers (SCSs). The secure communication techniques allows enterprise users to communicate data securely between on another without requiring a centralized system. The SCS provides the secure communication services, such as certification authentication, usually provided by the centralized system. The non-centralized secure communication services provide high fault-tolerance, so that the failure of any system, communication link or other infrastructure will only affect the communication sessions directly associated with the infrastructure experiencing failure.

Abstract: The invention is directed towards structures for use with micro-formed membrane ultrasonic transducers, and methods for fabricating the structures. In one embodiment, the transducer includes a planar member having a piezoelectric material and spaced apart electrodes disposed on the planar member and coupled to the piezoelectric material for applying an electric field to the layer, and an acoustic backing member joined to the electrodes. In another embodiment, the transducer includes a planar member having a piezoelectric material that adjoins a semiconductor material, the semiconductor material having monolithically formed active circuits formed in the layer and coupled to the piezoelectric material. In still another embodiment, the transducer includes a planar member having a piezoelectric material, and an acoustic backing member having an adjoining layer of a semiconductor material having monolithically formed active circuits, the active circuits being coupled to the electrodes.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: The invention provides techniques for validating security credentials locally within an enterprise. For example, a trust server within the enterprise intercepts a validation request from a secure electronic email service being used by a client within the enterprise. The trust server accesses security credential information, which may be maintained in a directory, to answer for the validation request. When the trust server is unable to answer the validation request, the trust server queries a bridge service provider, which associates the trust server with trust servers maintained by other enterprises, for the security credential information necessary for validation. The bridge service provider forwards the query to the appropriate one the trust servers of another enterprise. The trust server of the other enterprise returns the necessary security credential information, which the bridge service provider relays to the querying trust server for validation.

Abstract: Techniques are described for constructing and maintaining secure communities over a computer network, such as the Internet. In particular, the techniques allow security to be integrated and managed in a “directory-centric” fashion. In other words, the techniques described herein allow a community of trusted members to easily be managed via one or more online directories rather than hierarchical certification authorities. A system includes, for example, a server having a directory of members of a network community, wherein the directory stores data defining digital identities of the members for securely exchanging information with the members. A software application executing on a network device coupled to the server accesses the directory and exchanges the information between the members in accordance with the digital identities of the members.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic transducer array element operating in the k31 mode is formed by two piezoelectric subelements joined to form a 2—2 composite by a conductive filler material. An energizing potential is applied to the conductive filler material, and a return potential is applied to the outer opposing faces of the subelements. Preferably the conductive filler material comprises a conductive epoxy. Arrays of such elements in one and two dimensions are formed with the conductive epoxy in alternating kerfs in a row being connected to the opposing polarities of an energizing potential.

Abstract: A multiplane TEE probe is provided in which an aluminum sheet is embedded in the acoustic lens in front of the transducer to dissipate heat which accumulates in the lens. The embedded aluminum foil sheet in front of the transducer helps reduce such heat buildup by spreading out heat which develops at hot spots and conducting the heat trapped in the lens material to a heatsink mass behind the transducer and away from the patient contacting surface of the probe. A mylar sheet covers the front of the transducer. The inner surface of the mylar sheet is aluminized. This aluminum layer in the inner surface of the cover serves a like purpose.

Abstract: A multiplane TEE probe is provided in which rotation of the ultrasonic transducer is motor controlled. The motor is controlled to rotate the transducer either clockwise or counterclockwise, and at either a high rotational speed or a low rotational speed. The motor is also automatically controlled to drive the transducer to a predetermined home position. The transducer tip of the probe is detachably connected to the gastroscope tube. An aluminum sheet is embedded in the acoustic lens in front of the transducer to dissipate heat which accumulates in the lens. The gastroscope tube includes an articulating section formed of a plurality of matching cylindrical links which form alternating pivot axes from one link to the next. The pivot range of each link with respect to an adjoining link is controlled by opposing limit stops orthogonally located with respect to the pivot points of the links.