Patents Assigned to The Board of Trustees of the Leland
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Patent number: 5264800Abstract: A Monolithic Microwave Integrated Circuit (MMIC) for capturing transients in the GHz range is disclosed. The device includes a transmission line formed in a GaAs substrate. The transmission line includes a number of threshold devices forming shunts on the transmission line. The threshold devices are positioned at predetermined locations with respect to one another. A reference signal and an unknown signal are counter-propagated along the transmission line. When the two signals collide, they produce a collision voltage which exceeds the threshold voltage of the threshold devices. The voltage information is distributed along the predetermined length of several threshold devices. Thus, amplitude, phase, and timing information regarding the two signals may be obtained. This information may be utilized for triggering, clock interpolation, data demodulation, and other applications.Type: GrantFiled: September 15, 1992Date of Patent: November 23, 1993Assignee: The Board of Trustees of the Leland Stanford, Jr. Univ.Inventor: Alistair D. Black
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Method of noninvasive motion analysis by using forced closure of phase contrast MRI maps of velocity
Patent number: 5257625Abstract: Measures of a velocity component during a plurality of time frames of cyclical motion of a region of interest are obtained using contrast cine MRI techniques. A position error is obtained between a known starting location and a calculated cyclical motion and is used for recalculating cyclical motion of the region of interest using the measures of velocity and the measure of error in velocity.Type: GrantFiled: April 9, 1992Date of Patent: November 2, 1993Assignee: Board of Trustees of the Leland Stanford Junior UniversityInventor: Norbert J. Pelc -
Patent number: 5257626Abstract: Measures of a velocity component during a plurality of time frames of cyclical motion of a region of interest are obtained using contrast cine MRI techniques. Trajectories of the region of interest are calculated in a backward direction and in a forward direction. The trajectories are then combined to define a motion trajectory. The forward and backward trajectories are weighted prior to combining with the forward trajectory being more heavily weighted for early frames and the backward trajectory being more heavily weighted for late frames.Type: GrantFiled: July 28, 1992Date of Patent: November 2, 1993Assignee: Board of Trustees of the Leland Stanford Junior UniversityInventors: Norbert J. Pelc, Douglas C. Noll, John M. Pauly
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Patent number: 5257544Abstract: The present invention provides for an inspection system and method for detecting defects in test objects which includes means for generating expansion inducing energy focused upon the test object at a first location, such expansion being allowed to contract, thereby causing pressure wave within and on the surface of the test object. Such expansion inducing energy may be provided by, for example, a laser beam or ultrasonic energy. At a second location, the amplitudes and phases of the acoustic waves are detected and the resonant frequencies' quality factors are calculated and compared to predetermined quality factor data, such comparison providing information of whether the test object contains a defect. The inspection system and method also includes means for mounting the bearing ball for inspection.Type: GrantFiled: January 22, 1992Date of Patent: November 2, 1993Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: B. T. Khuri-Yakub, Chung-Kao Hsieh
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Patent number: 5256996Abstract: An integrated coplanar strip nonlinear transmission line comprising a substrate of gallium arsenide upon which a heavily doped buried layer and a lightly doped surface layer of epitaxially grown gallium arsenide are grown. Two parallel conductors are integThis work was funded by the United States Government's Office of Naval Research under contract No. N99914-85-K-0381. The United States Government has a paid up license in this technology.Type: GrantFiled: July 6, 1992Date of Patent: October 26, 1993Assignee: The Board of Trustees of the Leland Stanford, Junior UniversityInventors: Robert A. Marsland, Mark J. W. Rodwell, David M. Bloom
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Patent number: 5255274Abstract: A laser source comprises an optical fiber doped with a homogeneously broadened lasing medium, preferably with Erbium, pumped by a laser pump source and an intracavity acousto-optic modulator. When the acousto-optic modulator is driven by a variable frequency source, the Erbium fluorescence line emitted by the Erbium-doped optical fiber can be electronically tuned. In another embodiment, an electronic sweep waveform is used to frequency modulate the acoustic signal produced by the acousto-optic modulator. Without the low-rate frequency modulation, Erbium in a silica optical fiber is a mostly homogeneously broadened gain medium with a narrow laser linewidth. When measured on a long time scale, low-rate frequency modulation provides a broader spectral width, on the order of 19 nm, which makes such a source an ideal source for certain optical applications such as fiber optic gyroscopes.Type: GrantFiled: June 8, 1992Date of Patent: October 19, 1993Assignee: The Board of Trustees of the Leland Stanford UniversityInventors: Paul F. Wysocki, Michel J. F. Digonnet, Byoung Y. Kim
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Patent number: 5250898Abstract: Disclosed is a method of detecting NMR signals indicative of a short T.sub.2 species in the presence of a long T.sub.2 species by utilizing magnetization transfer between species without requiring an auxiliary RF amplifier and with reduced power deposition (SAR). One or more zero degree RF pulses are applied to a body containing the short T.sub.2 species and the long T.sub.2 species with the pulses being at the resonant frequency. The RF pulses provides selective magnetization saturation of the short T.sub.2 species, and the RF pulses are spaced in time to allow magnetization transfer from the short T.sub.2 species to the long T.sub.2 species. Gradients can then be applied to the body for signal localization with signals detected from the long T.sub.2 species due to magnetization transfer from the short T.sub.2 species being indicative of the presence of the short T.sub.2 species. The signals are indicative also of the magnetization transfer between species.Type: GrantFiled: August 9, 1991Date of Patent: October 5, 1993Assignee: Board of Trustees of the Leland Stanford Junior UniversityInventors: Bob S. Hu, Steven M. Conolly
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Patent number: 5250818Abstract: MOS transistors are formed in thin films of Ge/Si alloys (Ge.sub.x Si.sub.1-x). According to the process of the present invention, polycrystalline films of Ge/Si are deposited using commercially-available LPCVD equipment, which in the preferred process uses silane and germane as the sources of Ge and Si. The deposited Ge.sub.x Si.sub.1-x films are polycrystalline at temperatures for processing down to as below 400.degree. C., and the films can be doped heavily by ion implantation and annealing at temperatures as low as 600.degree. C. to give high mobility and dopant activation yielding very low resistivity. By carrying out the annealing step in the formation of the thin film transistors in the temperature range of 400.degree. to 500.degree. C., the films provide very large grain size, minimizing the impact of grain boundaries in the polycrystalline films where the thin film transistors are to be formed. As a result, thin film MOS transistors are fabricated at temperatures below 500.degree. C.Type: GrantFiled: March 1, 1991Date of Patent: October 5, 1993Assignee: Board of Trustees of Leland Stanford UniversityInventors: Krishna C. Saraswat, Tsu-Jae King
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Patent number: 5243284Abstract: The acquisition of radial lines in 2-D Fourier space (k-space) allows the realization of the extremely short echo times useful in the imaging of short-T.sub.2 species and flow using Magnetic Resonance (MR). The disadvantage of this imaging method, which is also known as projection reconstruction, is that in order to prevent aliasing at a given resolution, .pi. times as many excitations are required as the conventional 2-D Fourier transform or spin-warp acquisition. Disclosed is an acquisition and reconstruction method that reduces the required number of radial lines and excitations by using the properties that projections are real or have slowly varying phase and the at radial acquisition methods are oversampled at the center of k-space. This method preserves resolution while reducing imaging time at the expense of signal-to-noise ratio (SNR). This has been verified with both phantom and human subjects.Type: GrantFiled: July 24, 1991Date of Patent: September 7, 1993Assignee: Board of Trustees of the Leland Stanford Junior UniversityInventor: Douglas C. Noll
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Patent number: 5241470Abstract: A method is provided for determining the packing conformation of amino acid side chains on a fixed peptide backbone. Using a steric interaction potential, the side chain atoms are rotated about carbon-carbon bonds such that the side chains preferably settle in a low energy packing conformation. Rotational moves are continued according to a simulated annealing procedure until a set of low energy conformations are identified. These conformations represent the structure of the actual peptide. The method may be employed to identify the packing configuration of mutant peptides.Type: GrantFiled: January 21, 1992Date of Patent: August 31, 1993Assignee: The Board of Trustees of the Leland Stanford UniversityInventors: Christopher Lee, Subramanian Subbiah
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Patent number: 5240542Abstract: Two pieces of composite material are simultaneously joined together throughout an interface between the two pieces, by induction heating the interface region with an induction coil placed, at least in part, adjacent to the bonding region, and forcing the composite material at the interface together while heating. The approach is particularly useful in joining pieces having "long interfaces" whose longitudinal dimension is substantially larger than its transverse dimension, for example the long interfaces between aircraft wing stiffeners and skins. The induction coil is configured so that, at any one longitudinal location along the interface, the primary current flowing therethrough does not flow in opposite directions in the portions of the coil overlying the interface, and preferably flows in substantially the same direction throughout the interface. Unheated "cold spots" in the interface being bonded, which would not bond properly, are thereby avoided.Type: GrantFiled: September 6, 1990Date of Patent: August 31, 1993Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Alan K. Miller, Wendy Lin
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Patent number: 5239066Abstract: Nucleic acids encoding all or part of a Yersinia ail gene are provided. The nucleic acid comprises at least 50 base pairs of a Yersinia ail gene in isolated form or consists or a fragment consisting essentially of at least 50 base pairs but not more than 50 kilo base pairs of a Yersinia ail gene. Such nucleic acids can also be operably linked to transcriptional and translational initiation and termination sequences which are functional in a microorganism host.Type: GrantFiled: January 23, 1991Date of Patent: August 24, 1993Assignee: The Board of Trustees of Leland Stanford Jr. UniversityInventors: St. Geme, III: Joseph W., Stanley Falkow, Ralph Isberg, Virginia Miller
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Patent number: 5235404Abstract: A method and apparatus for measuring nonreciprocal optical effects contemplates directing two circularly polarized optical beams having a known phase relation to each other at a sample, and detecting the difference in phase between the two beams after they have encountered the sample. In a transmission measurement the two circularly polarized beams have the same handedness, but pass through the sample in opposite directions. In a reflection measurement, the two circularly polarized beams have opposite handedness, but encounter the sample in the same direction. In a particular embodiment of the invention a linearly polarized beam is introduced into a Sagnac interferometer and split into two linearly polarized beams which are ultimately recombined.Type: GrantFiled: June 27, 1991Date of Patent: August 10, 1993Assignee: Board of Trustees, Leland Stanford Junior University, Stanford UniversityInventors: Martin M. Fejer, Aharon Kapitulnik, Kenneth A. Fesler
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Patent number: 5233991Abstract: The oxygen saturation of blood is determined by obtaining spin-spin relaxation time (T2.sub.b) of the fluid using magnetic resonance imaging techniques. A simplified model relates oxygen saturation of blood to measured spin-spin relaxation time. A pulse sequence is given for in vivo estimation of T2.sub.b including a plurality of 180.degree. refocusing RF signals which are equally spaced in time. The last refocusing pulse is slice selective. Fat signal is suppressed by initially using a short inversion recovery sequence followed by a frequency selective 90.degree. pulse that excites only water protons.Type: GrantFiled: August 8, 1991Date of Patent: August 10, 1993Assignee: Board of Trustees of the Leland Stanford Junior UniversityInventor: Graham A. Wright
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Patent number: 5233301Abstract: A high resolution NMR signal is obtained for a thin slice through a body by combining signals in which excitation k-space is covered in two or more excitations. An RF excitation pulse is applied along with an oscillating (e.g. triangular, trapezoidal, sinusoidal) wave modulated magnetic gradient with the RF pulse having nulls corresponding to zero values of the gradient. The RF pulse is applied a second time with the magnetic gradient inverted NMR signals detected following the application of the RF excitation pulses are summed. Minimum phase RF pulses can be employed to reduce signal dropout and reduce artifacts.Type: GrantFiled: August 16, 1990Date of Patent: August 3, 1993Assignee: Board of Trustees of the Leland Stanford Junior UniversityInventors: Craig H. Meyer, John M. Pauly
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Patent number: 5232565Abstract: In the capillary electrophoretic system, the components of a sample to be separated and detected are labelled by a radioactive material which emits gamma rays or beta particles with energy high enough to penetrate the electrolyte and the capillary tube. A semiconductor detector outside the tube and placed adjacent to the tube detects the gamma rays or beta particles in order to detect the presence of the components of the sample. A weaker radio-label may also be used in conjunction with scintillating material which is introduced together with the sample into the tube or through a different tube. Alternatively, the scintillating material may be placed inside the tube or made a part of the tube. The scintillating material emits light in response to radiation from the radio labels on the components of the sample to enable detection of the component.Type: GrantFiled: April 22, 1992Date of Patent: August 3, 1993Assignee: The Board of Trustees of the Leland Standford Junior UniversityInventors: Richard N. Zare, Stephen L. Pentoney, Jr., John W. Frost, Jeff Quint
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Patent number: 5231349Abstract: Three classes of active probes all with coaxial inputs and coplanar waveguide probe tips are described. A millimeter-wave active probe for generating signals with frequencies about 50 gHz and supplying same to millimeter-wafer including a substrate upon which a frequency multiplier consisting of filter sections and impedance matching sections and nonlinear elements are integrated in uniplanar transmission line medium. Also disclosed is a harmonic mixer probe to step down RF received from an integrated circuit to a lower frequency by mixing it with the harmonics of a local oscillator signal.Type: GrantFiled: December 24, 1990Date of Patent: July 27, 1993Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Gholamreza Majidi-Ahy, David M. Bloom
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Patent number: 5229412Abstract: Compounds that selectively bind 5-HT.sub.1A receptors in preference to other 5-HT receptors are provided along with methods for their use. Such compounds have the formula ##STR1## wherein A is an aromatic group selected to provide, with the glycidyl residue that forms the next portion of the molecule, a 5-HT-like portion of the molecule that represents the primary binding site of the molecule with a 5-HT receptor: X represents a quarternary carbon and its attached alkyl groups: Y represents a hydrocarbon linking group: Z represents hydrogen or an organic group containing up to 12 carbon and/or heteroatoms in its skeletal structure: and R.sup.1 and R.sup.2 independently represent hydrogen or an alkyl group. The aromatic group is most preferably indole or an indole derivative.Type: GrantFiled: March 25, 1988Date of Patent: July 20, 1993Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Stephen J. Peroutka, Josef Pitha
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Patent number: 5227911Abstract: The combination of a resonator having total internal reflection with a coupler providing coupling via frustrated total internal reflection. Both linear and non-linear embodiments are described. The linear embodiment is a spectrum analyzer. The non-linear embodiment is a second harmonic generator, although modifications are described for turning the same into an optical parametric oscillator.Type: GrantFiled: February 28, 1992Date of Patent: July 13, 1993Assignee: The Board of Trustees of the Leland Stanford, Jr. UniversityInventors: Stephan Schiller, Martin M. Fejer, Andreas Sizmann, Robert L. Byer
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Patent number: 5223114Abstract: An on-column conductivity detector for microcolumn electrokinetic separation systems is disclosed. The detector is based on the column itself, the column having a largest internal cross-sectional dimension of 500 microns or less and includes one or more sensing electrodes positioned directly upon or immediately adjacent to (i.e. contiguous with) the wall of the column into communication with the analyte stream so as to present no dead volume and no increase in cross-sectional area to the fluid flow. In one embodiment, this conductivity detector has a single on-column electrode, located immediately adjacent to the exit end of the column. In a preferred embodiment, this conductivity detector has one or more pairs of on-column sensing electrodes and these paired electrodes are located directly across from each other on the microcolumn, to minimize potential across the electrodes and concomitant electrochemical reactions.Type: GrantFiled: August 8, 1991Date of Patent: June 29, 1993Assignee: Board of Trustees of the Leland Stanford Junior UniversityInventors: Richard N. Zare, Xiao-Hua Huang, Joseph Pang