Abstract: The present invention relates to an electromagnetic device for non-contact injection of strong modulated (0-1000 Hz) electric fields with intensity of 1-2 volts per centimeter into a whole human body at the frequency band 10-500 kHz. The device of the present invention is a low-pass birdcage coil resonator with a very large number of rungs, with two inductively coupled loop feeds, and with a high quality factor of 300.

Abstract: In various embodiments, a method for performing quality control on a gasket material for use in a cell assembly in a high-pressure cubic press is disclosed. In an embodiment, the method includes determining at least one physical characteristic of the gasket material using a nondestructive testing technique, and predicting a moisture content for the tested gasket material at least partially based on the at least one physical characteristic. In an embodiment, the method includes determining a dissipation factor for the gasket material using an electromagnetic energy frequency testing technique, and predicting a moisture content for the tested gasket material at least partially based on the dissipation factor and a dissipation factor-moisture content calibration curve for the gasket material.

Abstract: Embodiments of the invention relate to electrical impedance tomography testing systems and methods for non-destructively testing a polycrystalline diamond element (e.g., a polycrystalline diamond table of a polycrystalline diamond compact or a freestanding polycrystalline diamond table) using electrical impedance tomography to locate one or more high-electrical-conductivity regions (e.g., one or more regions of poorly sintered diamond crystals and/or high-metal-solvent catalyst content) and/or one or more low-electrical-conductivity regions (e.g., porosity and/or cracks) in the tested polycrystalline diamond element. Further embodiments relate to a rotary drill bit including at least one polycrystalline diamond compact that has been selectively positioned so that one or more high-electrical-conductivity regions of a polycrystalline diamond table thereof identified using the non-destructive testing systems and methods disclosed herein are not positioned to engage a subterranean formation during drilling.

Abstract: A microstrip-based RF coil for use in an MRI apparatus constructed to perform human head and extremity imaging according to one embodiment of the present invention includes a coil former defined by an inner core member and a shield support that surrounds the inner core member. An outer surface of the shield support supports a conductive segmented shield and a plurality of conductive strip lines are disposed on an inner surface of the inner core module and extend parallel to a longitudinal axis thereof. According to one aspect of the present invention, all of the strip lines are not homogenous so as to introduce asymmetry into the coil design.

Abstract: Radio frequency (RF) coil configurations and methods are disclosed. Non-magnetic elements may be used in combination with an RF coil. The non-magnetic elements may be metal. The non-magnetic metal elements may be designed and configured to facilitate tuning of an RF coil, and to modify a magnetic field produced by an RF coil. The non-magnetic metal elements may also be used in connection with a RF receiver coil to control the region from which the receiver coil detects signals. The configurations and methods described may be used in various RF applications, including magnetic resonance imaging (MRI).

Abstract: A microstrip-based RF coil for use in an MRI apparatus constructed to perform human head and extremity imaging according to one embodiment of the present invention includes a coil former defined by an inner core member and a shield support that surrounds the inner core member. An outer surface of the shield support supports a conductive segmented shield and a plurality of conductive strip lines are disposed on an inner surface of the inner core module and extend parallel to a longitudinal axis thereof. According to one aspect of the present invention, all of the strip lines are not homogenous so as to introduce asymmetry into the coil design.

Abstract: A dual-tuned volume coil for performing MR imaging according to one embodiment includes an inner cylinder having a first coil structure disposed on an inner surface thereof and a second coil structure disposed on an outer surface thereof. The first coil structure operates at a first resonance frequency and the second coil structure operates at a second resonance frequency. The volume coil includes an outer shield disposed about the inner cylinder, with the first and second coil structure being connected to the outer shield by means of a plurality of capacitors.

Abstract: In one aspect, a restraining assembly for an awake animal within a magnetic resonance imaging (MRI) device is provided and includes a body restrainer having a first part and a second part that hold a body of the awake animal therebetween. The assembly is of a dual coil design in that it has a volume coil for generating an excitation RF signal and an RF surface coil for receiving an RF response from the animal. The assembly further includes components that serve to restrain movements of the animal, thereby eliminating motion artifacts during the MRI procedure.

Abstract: A microstrip-based RF coil for use in an MRI apparatus constructed to perform human head imaging is provided and includes (a) a cylindrical non-magnetic core module having an outer surface and a longitudinal axis, a cylindrical bore extending through the core module along the longitudinal axis and defining an inner surface; and a plurality of conductive strip lines. The strip lines extend parallel to the longitudinal axis on the outer surface of the core module. The coil is constructed such that one or more of the conductive strips are divided into conductive microstrip segments with one or more tuning capacitors being bridged between two adjacent microstrip segmented sections of the conductive strip. The coil also include a shield support cylinder that is disposed concentrically about the core module and is spaced therefrom to receive the tuning capacitors.

Abstract: A dual-tuned volume coil for performing MR imaging according to one embodiment includes an inner cylinder having a first coil structure disposed on an inner surface thereof and a second coil structure disposed on an outer surface thereof. The first coil structure operates at a first resonance frequency and the second coil structure operates at a second resonance frequency. The volume coil includes an outer shield disposed about the inner cylinder, with the first and second coil structure being connected to the outer shield by means of a plurality of capacitors.

Abstract: Multi-modal coils for coupling MRI RF signals from an anatomical region(s) to be imaged. The coil includes a segmented annular base ring conductor including a plurality of capacitances disposed between the segments, and at least one arcuate conductor symmetrically connected at each end to the base ring, one end terminating in direct contact with the base ring, the other end electrically connected to the base ring via two of the capacitive electrical connections. The RF coil is operable in multiple receiving modes in phase quadrature to establish a rotating magnetic field phasor orthogonal to the temporally constant uniform magnetic field of the magnetic resonance instrument. The RF coil can be combined with a second RF coil to simultaneously image two anatomical regions.

Abstract: A microstrip-based RF coil for use in an MRI apparatus constructed to perform human head imaging is provided and includes (a) a cylindrical non-magnetic core module having an outer surface and a longitudinal axis, a cylindrical bore extending through the core module along the longitudinal axis and defining an inner surface; and a plurality of conductive strip lines. The strip lines extend parallel to the longitudinal axis on the outer surface of the core module. The coil is constructed such that one or more of the conductive strips are divided into conductive microstrip segments with one or more tuning capacitors being bridged between two adjacent microstrip segmented sections of the conductive strip. The coil also include a shield support cylinder that is disposed concentrically about the core module and is spaced therefrom to receive the tuning capacitors.

Abstract: Multi-modal coils for coupling MRI RF signals from an anatomical region(s) to be imaged. The coil includes a segmented annular base ring conductor including a plurality of capacitances disposed between the segments, and at least one arcuate conductor symmetrically connected at each end to the base ring, one end terminating in direct contact with the base ring, the other end electrically connected to the base ring via two of the capacitive electrical connections. The RF coil is operable in multiple receiving modes in phase quadrature to establish a rotating magnetic field phasor orthogonal to the temporally constant uniform magnetic field of the magnetic resonance instrument. The RF coil can be combined with a second RF coil to simultaneously image two anatomical regions.

Abstract: The present invention relates to systems and methods of performing magnetic resonance imaging (MRI) in awake animals. The invention utilizes head and body restrainers to position an awake animal relative to a radio frequency dual coil system operating in a high field magnetic resonance imaging system to provide images of high resolution without motion artifact.

Abstract: In one aspect, a restraining assembly for an awake animal within a magnetic resonance imaging (MRI) device is provided and includes a body restrainer having a first part and a second part that hold a body of the awake animal therebetween. The assembly is of a dual coil design in that it has a volume coil for generating an excitation RF signal and an RF surface coil for receiving an RF response from the animal. The assembly further includes components that serve to restrain movements of the animal, thereby eliminating motion artifacts during the MRI procedure.

Abstract: The present invention relates to systems and methods of performing magnetic resonance imaging (MRI) in awake animals. The invention utilizes head and body restrainers to position an awake animal relative to a radio frequency dual coil system operating in a high field magnetic resonance imaging system to provide images of high resolution without motion artifact.

Abstract: The present invention relates to systems and methods of performing magnetic resonance imaging (MRI) in awake animals. The invention utilizes head and body restrainers to position an awake animal relative to a radio frequency dual coil system operating in a high field magnetic resonance imaging system to provide images of high resolution without motion artifact.