Abstract: A passive MRI enhancing embodiment includes a plurality of resonators and increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image. An isolator embodiment has a nonlinear resonator controllably configurable alternately into an isolation configuration and a transmission configuration, and a second resonator.

Abstract: A passive MRI enhancing embodiment includes a plurality of resonators and increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image. An isolator embodiment has a nonlinear resonator controllably configurable alternately into an isolation configuration and a transmission configuration, and a second resonator.

Abstract: A bilayler metamaterial silencer allows substantial fluid through the apparatus, while mitigating the propagation of sound through the apparatus, and while providing a form factor that is significantly more compact than previously-known devices. Moreover, illustrative embodiments allow a designer to specify one or both of the frequency or frequencies at which the apparatus mitigates sound propagation, and/or the bandwidth around the frequency or frequencies at which the apparatus mitigates sound propagation.

Abstract: A bilayler metamaterial silencer allows substantial fluid through the apparatus, while mitigating the propagation of sound through the apparatus, and while providing a form factor that is significantly more compact than previously-known devices. Moreover, illustrative embodiments allow a designer to specify one or both of the frequency or frequencies at which the apparatus mitigates sound propagation, and/or the bandwidth around the frequency or frequencies at which the apparatus mitigates sound propagation.

Abstract: A passive MRI enhancing embodiment includes a plurality of resonators and increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image. An isolator embodiment has a nonlinear resonator controllably configurable alternately into an isolation configuration and a transmission configuration, and a second resonator.

Abstract: A passive MRI enhancing embodiment includes a plurality of resonators and increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image. An isolator embodiment has a nonlinear resonator controllably configurable alternately into an isolation configuration and a transmission configuration, and a second resonator.

Abstract: A passive MRI enhancing embodiment includes a plurality of resonators and increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image. An isolator embodiment has a nonlinear resonator controllably configurable alternately into an isolation configuration and a transmission configuration, and a second resonator.

Abstract: A bilayler metamaterial silencer allows substantial fluid through the apparatus, while mitigating the propagation of sound through the apparatus, and while providing a form factor that is significantly more compact than previously-known devices. Moreover, illustrative embodiments allow a designer to specify one or both of the frequency or frequencies at which the apparatus mitigates sound propagation, and/or the bandwidth around the frequency or frequencies at which the apparatus mitigates sound propagation.

Abstract: A bilayer metamaterial silencer allows substantial fluid through the apparatus, while mitigating the propagation of sound through the apparatus, and while providing a form factor that is significantly more compact than previously-known devices. Moreover, illustrative embodiments allow a designer to specify one or both of the frequency or frequencies at which the apparatus mitigates sound propagation, and/or the bandwidth around the frequency or frequencies at which the apparatus mitigates sound propagation.

Abstract: A passive apparatus including a plurality of resonators increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Moreover, the apparatus enhances specimen safety by substantially avoiding unwanted generation of an electric field, or an increase in the electric field component of the RF energy. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image.

Abstract: A bilayler metamaterial silencer allows substantial fluid through the apparatus, while mitigating the propagation of sound through the apparatus, and while providing a form factor that is significantly more compact than previously-known devices. Moreover, illustrative embodiments allow a designer to specify one or both of the frequency or frequencies at which the apparatus mitigates sound propagation, and/or the bandwidth around the frequency or frequencies at which the apparatus mitigates sound propagation.

Abstract: A passive apparatus including a plurality of resonators increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Moreover, the apparatus enhances specimen safety by substantially avoiding unwanted generation of an electric field, or an increase in the electric field component of the RF energy. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image.

Abstract: A passive apparatus including a plurality of resonators increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Moreover, the apparatus enhances specimen safety by substantially avoiding unwanted generation of an electric field, or an increase in the electric field component of the RF energy. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image.

Abstract: A passive apparatus including a plurality of resonators increases signal-to-noise ratio of radiofrequency signals emitted by a specimen and captured by an MRI machine. The apparatus increases the magnetic field component of radiofrequency energy during signal transmission from the MRI machine to the specimen, and/or reception of signals from the specimen to the MRI machine. Moreover, the apparatus enhances specimen safety by substantially avoiding unwanted generation of an electric field, or an increase in the electric field component of the RF energy. Use of the apparatus improves the images generated by the MRI machine, and/or reduces the time necessary for the MRI machine to capture the image.

Abstract: In a first aspect this invention provides methods comprising administering an aqueous contrast agent to the vascular system of a subject, and performing a magnetic resonance scan to detect the MR signal enhancement effects of the aqueous contrast agent. In embodiments the magnetic resonance scan comprises applying at least one pulse sequence selected from a PD-weighted pulse sequence, a T1-weighted pulse sequence, a T2-weighted pulse sequence, and a D-weighted pulse sequence. In embodiments the magnetic resonance scan comprises applying a T1-weighted pulse sequence. A system for performing perfusion MRI comprising an aqueous contrast solution and an injection apparatus configured to provide a maximum injection rate of the aqueous contrast solution to a subject vascular system of at least about 5 ml/s. is also provided.

Abstract: A device is provided which can serve one or more of the multiple functions of impeding rotation of a shaft de-coupled turbine rotor, selectively impeding rotation of a first spool of the engine, for example to permit a second spool to generate power for use in ground operation, and facilitating reduced aircraft ground speed.