Abstract: This invention provides small position sensors for applications where localized sensing in a small volume of space is needed but where measurement of large relative displacement is also necessary. The invention enables a surgeon to accurately position the tip of a catheter during minimally invasive therapy. The current invention further improves the quality of tactile feedback to a physician during catheter-based surgeries with an axial force sensor at the tip of the catheter that allows for the transmission of force information to the physician. One embodiment of this invention is a position sensor for active interventional catheters, where the sensor may be laser-machined shape memory alloy (SMA), and the catheter actuators may be heated SMA or wire-pulleys. Providing position feedback from a catheter during minimally invasive therapy allows for closed-loop control of the catheter tip position under computer-aided guidance and enable force feedback to the physician.

Abstract: A hydrogel-metal assembly is provided. An intervening polymer network is used to bond together a water-swollen hydrogel layer and a biocompatible surface-modified metallic layer. The hydrogel layer is a water-swollen hydrogel layer of at least two interpenetrating polymers. The surface of the biocompatible surface-modified metallic layer is surface-modified with an inorganic material. The intervening polymer network has been chemically grafted to the inorganic material of the biocompatible surface-modified metallic layer through bi-functional linker molecules. The intervening polymer network is further physically or chemically cross-linked with the polymers of the water-swollen hydrogel. The hydrogel-metal assembly can be adapted to form a medical device, medical implant, an artificial implant, an orthopedic implant, or at least as part of a joint.

Abstract: Surface modification methods for an interpenetrating polymer network (IPN) hydrogel to provide a basis for cell or tissue attachment are provided. The method involves the activation of functional groups on the surface of the IPN hydrogel. The activated functional groups are then reacted with amine-containing molecules or hydroxyl-containing molecules. The methods (i) can be performed in an aqueous environment and do not require the use of any organic solvent, (ii) do not require UV treatment, thereby avoiding denaturation of the IPN hydrogel or proteins, and/or (iii) can be performed as a one pot reaction.

Abstract: Techniques for the production of flow-oriented collagen gels using hydrodynamics to influence the assembly of collagen fibers. Highly concentrated monomeric solutions of collagen are subjected to shear and extensional flow as they are drawn onto a substrate to induce fibrillogenesis under a high Ph buffer. The produced gel captures the flow induced ordering of molecular collagen upon fibril formation. The depositing or the induction of fibrillogenosis occurs without the application of a magnetic field to the concentration of collagen. These highly oriented 3D scaffolds are capable inducing contact guidance and guiding mammalian cell growth. The collagen fibers mimic the construction of in vivo fibers with the characteristic D-periodicity and the integrin receptors on the fibroblasts respond to this organization. The industrial applications of three-dimensional collagen gels as a biomaterial are widespread from drug delivery to burn repair or tissue engineering system.

Abstract: The present invention provides a radiotherapy treatment apparatus that includes a treatment beam, a magnetic field disposed parallel collinear to the treatment beam, and a target that is disposed along the treatment beam. The treatment beam can be a charged particle beam, a proton beam, an electron beam, or a linear accelerator (Linac) beam. The magnetic field is from a magnetic resonance imager (MRI), a megavolt x-ray imager, or a kilovolt x-ray imager and is disposed to operate in coordination with operation of the treatment beam and to narrow the beam. The tumor is disposed to rotate with respect to the treatment beam and the magnetic field, or the treatment beam and the magnetic field are disposed to rotate up to 360° with respect to the target when mounted to a ring gantry. The apparatus can include a rotation angle dependent shim disposed to account for Earth's magnetic field.

Abstract: Automatic selection, recording and meaningful labeling of tracks from media streams is provided. Content information which relates to tracks currently being played and/or to previously played tracks is used to guide selection of tracks to be recorded and to provide meaningful labels for recorded tracks. This content information does not provide an advance schedule of tracks to be played in the future. A segment is temporarily recorded from a selected media stream. The content information relating to tracks in the segment is compared with previous user input (i.e., track preferences) to select tracks within the segment to be recorded. For each selected track, clipping is performed to identify track start and end times. Clipped tracks are recorded onto a suitable long-term recording medium, and labeled with a meaningful label derived from the content information. Content information can be derived by automatic analysis of the media stream.

Abstract: A distributed power control technique for wireless networking efficiently balances communication delay against transmitter power on each wireless link. Packets are transmitted over a wireless link from a transmitter to a receiver using a dynamically controlled transmit power level that is periodically updated at the transmitter. The transmit power is computed from i) an observed noise plus interference value of the wireless link and ii) a parameter that determines a balance between per-packet average delay and per-packet average power. In a preferred implementation, the dynamically controlled transmit power level is computed by minimizing the sum of an average delay cost and an average power cost, weighted by the parameter.

Abstract: The current invention provide a microfluidic valve having a housing that includes a microfluid control port disposed adjacent to a microfluid exhaust port, where a movable rigid material having a first diameter is disposed in the housing between the microfluid control port and the microfluid exhaust port. The housing further includes a microfluid pressure port having a first microfluid pressure. The microfluid pressure port is connected to the microfluid exhaust port by a microfluid valve orifice having a second diameter, where the first diameter is larger than the second diameter, and when a second microfluid pressure is applied to the control port the moveable rigid material closes the microfluid valve orifice, where the first microfluid pressure is greater than the second microfluid pressure.

Abstract: An orthotic foot device with a walking boot is provided. The orthotic foot device with a walking boot includes at least one boot wall having at least one guide disposed along an anteroposterior direction of the boot wall. At least one upright bar is disposed to attach to an individual's lower leg and is disposed to translatably engage the at least one guide. At least one fastener fixedly holds the at least one upright bar to the at least one guide when the at least one upright bar is desirably positioned the anatomical ankle axis and calf midline of a patient suffering from an injured Achilles tendon, hair line fractures of the foot and ankle, plantar fasciitis, diabetes, or other foot and ankle pathologies that require a cam boot.

Abstract: In a geo-security system, a device receives RF signals from multiple distinct classes of RF communication systems and extracts location-dependent signal parameters. A current geotag is computed from the parameters by fuzzy extractors involving quantization of the parameters and Reed-Solomon decoding to provide a reproducible unique geotag. The current geotag is compared with a stored geotag, and a geo-secured function of the device is executed based on the result of the comparison. The use of multiple signal sources of different types, combined with special fuzzy extractors provides a robust geotag that allows both lower false rejection rate and lower false acceptance rate.

Abstract: A method of reducing a total number of beam segments in a dose distribution for a radiation therapy field is provided.

Abstract: A transient blocking unit (TBU) is an arrangement of two or more transistors connected to each other in series such that they automatically switch off when a TBU current passing through these transistors exceeds a predetermined threshold. Voltage turnoff capability is provided for a TBU by adding a voltage comparison circuit to the TBU. The voltage comparison circuit provides gate voltages to one or more of the TBU transistors that tend to turn off the TBU transistors, if the voltage at the TBU output (i.e., the protected device output voltage) falls outside a predetermined range. The voltage provided by the voltage comparison circuit adds constructively to the gate voltages provided by normal TBU operation. Accordingly, TBU switch off can be driven by an over-current condition (TBU current out of range) and/or by an over-voltage condition (TBU output voltage out of range).

Abstract: The present invention provides a high-speed Quantum Efficiency (QE) measurement device that includes at least one device under test (DUT), at least one conditioned light source with a less than 50 nm bandwidth, where a portion of the conditioned light source is monitored. Delivery optics are provided to direct the conditioned light to the DUT, a controller drives the conditioned light source in a time dependent operation, and at least one reflectance measurement assembly receives a portion of the conditioned light reflected from the DUT. A time-resolved measurement device includes a current measurement device and/or a voltage measurement device disposed to resolve a current and/or voltage generated in the DUT by each conditioned light source, where a sufficiently programmed computer determines and outputs a QE value for each DUT according to an incident intensity of at least one wavelength of from the conditioned light source and the time-resolved measurement.

Abstract: A localized nanostructure growth apparatus that has a partitioned chamber is provided, where a first partition includes a scanning probe microscope (SPM) and a second partition includes an atomic layer deposition (ALD) chamber, where the first partition is hermetically isolated from the second partition, and at least one SPM probe tip of the SPM is disposed proximal to a sample in the ALD chamber. According to the invention, the hermetic isolation between the chambers prevents precursor vapor from damaging critical microscope components and ensuring that contaminants in the ALD chamber can be minimized.

Abstract: A wireless access point coherently receives signals transmitted from client devices and from interfering devices, measures noise and interference capture samples from the received signals, and computes a characterization of noise plus interference. Receive gains and threshold levels are adjusted based on the computed noise plus interference characterization. A set of weights for an interference suppression spatial filter are calculated from the measured noise and interference capture samples and used to produce a filtered signal by spatially filtering the received signals such that interference is spatially nulled in the filtered signal. The method may also include setting PHY parameters at the wireless access point based on the computed noise plus interference characterization. In some embodiments, a protection transmission is transmitted from the wireless access point, requesting connected client devices to suspend transmissions during a specified time period.

Abstract: Monitoring the status and behavior in a wireless network is provided. In a wireless network of operational nodes, one or more monitoring nodes are embedded in the network to monitor the status and behavior of the network without unintentionally disturbing the network. The monitoring nodes receive state information from the operational nodes. The operational nodes can be nodes in a wireless sensor network or a broadcast-only distributed wireless network. State information is sent in small state messages during the idle period of the communication frame of the operational node to be received by monitoring nodes. Transmission of state messages in the idle period for monitoring purposes does not disturb communication between operational nodes and can be energy efficient. The monitoring nodes can also intercept communications between operational nodes. Providing feedback to and influencing operational nodes are also provided.

Abstract: A current-limiting surge protection device is provided. The current-limiting surge protection device includes a pair of series connected normally on MOSFET's and a pair of voltage controlled normally off switches that are disposed to monitor a voltage across the normally on MOSFET pair. Here, the voltage controlled normally off switches close according to an excess threshold voltage across the MOSFET pair and reduces a gate drive potential of the normally on MOSFET pair to limit a current through the normally on MOSFET pair.

Abstract: A method of modifying properties of intrinsic tissue of an organ is provided. The method includes providing an organ, where a first electrode is disposed proximal to the organ first end. The first electrode has a surface area and insulator. A second electrode is disposed opposite the first electrode, where the organ is disposed between the first electrode and the second electrode. The second electrode has surface area and surface insulator. An organ-shaping device is provided that is disposed on the organ between the electrodes, where the organ-shaping device deforms the organ middle section along at least one lateral direction between the electrodes. An electric current is provided between the first second electrodes, where a current density gradient is provided by the electrode surface areas and the deformed organ middle section, and the properties of the intrinsic muscle tissue are modified according to the current density gradient.

Abstract: One or more quantum dots are used to control current flow in a transistor. Instead of being disposed in a channel between source and drain, the quantum dot (or dots) are vertically separated from the source and drain by an insulating layer. Current can tunnel between the source/drain electrodes and the quantum dot (or dots) by tunneling through the insulating layer. Quantum dot energy levels can be controlled with one or more gate electrodes capacitively coupled to some or all of the quantum dot(s). Current can flow between source and drain if a quantum dot energy level is aligned with the energy of incident tunneling electrons. Current flow between source and drain is inhibited if no quantum dot energy level is aligned with the energy of incident tunneling electrons. Here energy level alignment is understood to have a margin of about the thermal energy (e.g., 26 meV at room temperature).

Abstract: The present invention provides a device that measures at least one property of the liquid or gas, where the invention is a CMUT sensor that includes a substrate, a first layer disposed on the substrate, where the first layer includes a cavity, and a compound plate, where the compound plated includes a bottom plate, an intermediate plate and a top plate. According to the invention, the intermediate plate has at least one sample inlet, a sample cavity and at least one sample outlet, where the bottom plate is disposed on the first layer, and the cavity in the first layer is sealed by the compound plate. The cavity in the first layer can be a vacuum or contain a gas. The CMUT sensor can be disposed in an array of two or more sensors and connected electrically in parallel.