University of California

Brigham Young University

Siemens Mobility Gmbh

Siemens Industry, Inc.

Holger Schmidt

Aaron Roe Hawkins

Brian Joseph Hogan

Brian Harp

David W Deamer

William Dunbar

Heinrich Helmut Degen

A Nathan Edds

Nathan Clanney

Richard Bamfield

Stefan Fritschi

Jay Yocum

Philip Measor

Sergei Kuehn

Joshua Wayne Parks

Systems, methods, and techniques for optofluidic analyte detection and analysis using multi-mode interference (MMI) waveguides are disclosed herein. In some embodiments, spatially and spectrally multiplexed optical detection of particles is implemented on an optofluidic platform comprising multiple analyte channels intersecting a single MMI waveguide. In some embodiments, multi-stage photonic structures including a first stage MMI waveguide for demultiplexing optical signals by spatially separating different wavelengths of light from one another may be implemented. In some embodiments, a second stage may use single-mode waveguides and/or MMI waveguides to create multi-spot patterns using the demultiplexed, spatially separated light output from the first stage. In some embodiments, liquid-core MMI (LC-MMI) waveguides that are tunable by replacing a liquid core, heating/cooling the liquid core, and/or deforming the LC-MMI to change its width may be implemented in one or more of the analyte detection/analysis systems disclosed herein.

Optofluidic analyte detection systems using multi-mode interference waveguides

A grade crossing control system includes a track circuit with a grade crossing predictor (GCP) system coupled to rails of a railroad track at a grade crossing, wherein a railroad vehicle travelling on the railroad track causes a change of impedance when entering the track circuit, and wherein the GCP system generates grade crossing activation signals in response to the change of the impedance of the track circuit, wherein, for detecting the change of impedance, the GCP system includes a first transmitter transmitting a first signal over the track circuit and a first receiver detecting a first response signal, a second transmitter transmitting a second signal over the track circuit and a second receiver detecting a second response signal, wherein the first transmitter and the first receiver are preprogrammed to a first frequency, and wherein the second transmitter and the second receiver are preprogrammed to a second frequency.

Determination of train direction for bi-directional grade crossings

A disclosed system uses modulations of ionic current across a nanopore in a membrane to detect target molecules passing through the nanopore. This principle has been applied mainly to nucleic acid sequencing, but can also be used to detect other molecular targets such as proteins and small molecules. In addition, the system delivers target molecules to a nanopore to provide label-free single molecule analysis using a chip-based system. Target molecules are concentrated on microscale carrier beads, and the beads are delivered and optically trapped in an area within the capture radius of the nanopore. The target molecules are released from the beads and detected using nanopore current modulation. In addition, the disclosed system combines sample preparation (e.g. purification, extraction, and pre-concentration) with nanopore-based readout on a microfluidic chip. Finally, target molecules can be specifically bound to carrier beads and particles are positioned within the capture volume of a nanopore using a chip-based microfluidic platform proven to handle specific detection of molecular targets from milliliters of raw sample.

Systems and methods of delivering target molecules to a nanopore

Aspects of the disclosed embodiments generally relate to railway track circuits, in particular track circuits with continued distance monitoring and broken rail protection.

Track circuit with continued distance monitoring and broken rail protection

Spatially distributed optical excitation and integrated waveguides are used for ultrasensitive particle detection based on individual electrokinetic velocities of particles. In some embodiments, chip-integrated systems are used to identify individual particles (e.g., individual molecules) based on their velocity as they move through an optically interrogated channel. Molecular species may be identified and quantified in a fully integrated setting, allowing for particle analysis including molecular analysis that can operate at low copy numbers down to the level of single-cell lysates. In some embodiments, the single-particle velocimetry-based identification and/or separation techniques are applied to various diagnostic assays, including nucleic acids, metabolites, macromolecules, organelles, cell, synthetic markers, small molecules, organic polymers, hormones, peptides, antibodies, lipids, carbohydrates, inorganic and organic microparticles and nanoparticles, whole viruses, and any combination thereof.

Velocimetry-based identification of single proteins and other particles

A railroad crossing control system () includes a constant warning time device () with a control unit () configured to produce multiple signals, and a wheel sensing system () comprising at least one sensor () connected to a rail () of a railroad track () at a predetermined position (P), wherein the wheel sensing system () detects a presence of railroad vehicle travelling on the railroad track () such that the at least one sensor () detects wheels of the railroad vehicle using electromagnetic fields, wherein the wheel sensing system () provides speed values of the railroad vehicle to the constant warning time device (), and wherein the constant warning time device () produces a constant warning time signal for controlling a railroad crossing warning device in response to receiving the speed values of the wheel sensing system ().

Railroad crossing control system including constant warning time device and axle counter system

Disclosed herein are systems, methods, and techniques for optical detection of analytes (e.g., biomarkers or other objects) using a liquid-core waveguide in which the analytes are suspended in a high-index liquid inside a liquid channel of the waveguide. The term 'high-index' may indicate a refractive core index of the carrier liquid that is higher than or equal to that of one or more surrounding cladding layer(s) (e.g., ethylene glycol liquid inside a glass channel). In some embodiments, a method includes illuminating, by a light-source, one or more particles in a liquid-core waveguide, wherein the liquid-core waveguide comprises a first cladding layer having a first index of a refraction, and a hollow core comprising a liquid inside the hollow core, wherein the liquid has a second index of refraction higher than the first index of refraction; and detecting, by a detector, light emitted from the one or more particles.

High efficiency optical detection of biomolecules in micro-capillaries

A traffic control system () includes a railroad crossing control system () with a constant warning time device (), a wheel sensing system () with a sensor () connected to a rail () of a railroad track () at a predetermined position (P), and a communication network () interfacing with the railroad crossing control system () and the wheel sensing system () and adapted to transmit data. The wheel sensing system () provides speed values of a rail vehicle travelling on the railroad track (), wherein the speed values are transmitted to the railroad crossing control system () via the communication network () for producing a preemption signal for the traffic signal control system (). Further, a method for providing a preemption signal for a traffic signal control system () is described.

Traffic control system and method for providing a preemption signal

A combination of microvalves and waveguides may enable the creation of reconfigurable on-chip light sources compatible with planar sample preparation and particle sensing architecture using either single-mode or multi-mode interference (MMI) waveguides. A first type of light source is a DFB laser source with lateral gratings created by the light valves. Moreover, feedback for creating a narrowband light source does not have to be a DFB grating in the active region. A DBR configuration (Bragg mirrors on one or both ends of the active region) or simple mirrors at the end of the cavity can also be used. Alternately, ring resonators may be created using a valve coupled to a bus waveguide where the active gain medium is either incorporated in the ring or inside an enclosed fluid. The active light source may be activated by moving a fluid trap and/or a solid-core optical component defining its active region.

Physically operable and mechanically reconfigurable light sources

Provided is a device comprising a channel through and defined by a plurality of layers surrounding the channel, the channel connecting a first and a second chambers separated by the plurality of layers, wherein the plurality of layers comprise a first layer, a second layer; and a conductive middle layer disposed between the first and second layers, wherein the channel comprises (a) a first region defined by the first layer, denoted as an inlet, that is about 0.5 nm to about 100 nm in diameter and (b) a second region defined by the second layer, denoted as an outlet, wherein the inlet and the outlet are about 10 nm to about 1000 nm apart from each other, and wherein the first and second chambers and the middle layer are connected to a power supply. Also provided are methods of preparing and using the device, in particular for nucleic acid sequencing.

Two-chamber dual-pore device

A railway road crossing warning system () including a railway road crossing control unit () that may be selectively set to a primary or a secondary mode of operation is provided. In the primary mode of operation, the railway road crossing control unit is responsive to a primary activation signal () received from a primary activation-signal source (), such as a positive train control (PTC) system. In the event the primary activation signal from the primary activation-signal source is not available, railway road crossing control unit () is set to the secondary mode of operation, where the railway road crossing control unit is responsive to one or more signals () received from a secondary activation-signal source () including a railway-vehicle sensing system () electrically-decoupled from a railroad track (). Disclosed embodiments maintain operational robustness in the presence of changing weather and avoid variable electrical ballast conditions that otherwise could develop across the rails, while providing a cost-effective and reliable backup capability for a PTC-started crossing system.

Railway road crossing warning system with sensing system electrically-decoupled from railroad track

An optical waveguide comprises multiple layers of solid-state material disposed on a substrate. One of the layers is a lifting-gate valve made of a high refractive index material. The device provides for better optical confinement in microfluidic channels, and has the capability to integrate both optical signals and fluid sample processing. The optical paths on the chip are reconfigurable because of the use of a movable microvalve that guides light in one of its positions.

Reconfigurable microvalve optical waveguide

A computer implemented digital bridge that reduces the time and costs associated with designing and configuring hardware and/or logic for an application while also reducing the potential for errors during the process.

Digital bridge for drawing and configuration tools

A coded track circuit of a signaling control equipment to be located at a wayside location of a railway track is provided. The coded track circuit comprises a first track circuit card coupled to rails of the railway track to detect an absence of a train on the railway track, inform signallers and control relevant signals via track codes. The coded track circuit further comprises a second track circuit card coupled to rails of the railway track, the second track circuit card is inactive but ready to provide a warm-standby or a hot-standby such that the second track circuit card to take over control from the first track circuit card should the first track circuit card fails.

Warm or hot standby track card module for use on a wayside of a railway system

A lamp driver card to control lighting of a lamp load located on a wayside of a railway system is provided. The lamp driver card comprises a light source controller module including at least one channel having a semiconductor switch or a relay to receive power on a copper cable sized at a selected gauge size from a power source to turn ON or OFF the lamp load. The light source controller module is configured to support a multi-voltage rating range operation extended from a limited voltage to an extended operating voltage and a current rating to light the lamp load such that the light source controller module is compatible with relatively higher DC/AC voltages. The copper cable is sized at the selected gauge size of a first size to a second size based on a selected voltage rating of a first voltage system or a second multi-voltage ranges system.

Growing community of inventors

Capitola, CA, United States of America

Holger Schmidt