摘要:
Medical devices for in vivo medical applications are disclosed. The medical devices are constructed of shape memory polymer (SMP) materials capable of assuming a memory shape at physiological temperatures. These medical devices may be used in surgical procedures and in both vascular and non-vascular applications. These SMP medical devices have a post-implantation memory shape that is substantially identical to or slightly larger than the insertion site to adapt to vessel growth or size changes. SMP medical devices may be formed as stents or occlusion devices (i.e., plugs) having a number of different structural features. The SMP medical devices may be formed from a first monomer and a second cross-linking monomer, wherein the weight percentages of the first and second monomers are selected by performing an iterative function to reach a predetermined glass transition temperature (Tg) and a predetermined rubbery modulus to optimize post-implantation memory shape properties of the devices.
摘要:
Transcervical contraceptive devices (TCDs) are disclosed. The TCDs are constructed of shape memory polymer (SMP) materials capable of assuming a memory shape at physiological temperatures. These SMPTCDs (410) have a post-implantation memory shape that is substantially identical to or slightly larger than the insertion site (420) to adapt to changes that may occur in a fallopian tube. The SMPTCDs (410) may be formed as occlusion devices (i.e., plugs) having a number of different structural features. The SMPTCDs (410) may provide for a temporary or permanent means of contraception.
摘要:
A synchrocyclotron comprises a resonant circuit that includes electrodes having a gap therebetween across the magnetic field. An oscillating voltage input, having a variable amplitude and frequency determined by a programmable digital waveform generator generates an oscillating electric field across the gap. The synchrocyclotron can include a variable capacitor in circuit with the electrodes to vary the resonant frequency. The synchrocyclotron can further include an injection electrode and an extraction electrode having voltages controlled by the programmable digital waveform generator. The synchrocyclotron can further include a beam monitor. The synchrocyclotron can detect resonant conditions in the resonant circuit by measuring the voltage and or current in the resonant circuit, driven by the input voltage, and adjust the capacitance of the variable capacitor or the frequency of the input voltage to maintain the resonant conditions. The programmable waveform generator can adjust at least one of the oscillating voltage input, the voltage on the injection electrode and the voltage on the extraction electrode according to beam intensity and in response to changes in resonant conditions.
摘要:
A system includes a patient support and an outer gantry on which an accelerator is mounted to enable the accelerator to move through a range of positions around a patient on the patient support. The accelerator is configured to produce a proton or ion beam having an energy level sufficient to reach a target in the patient. An inner gantry includes a robotic arm capable of directing an aperture for directing the proton or ion beam towards the target.
摘要:
Among other things, an accelerator is mounted on a gantry to enable the accelerator to move through a range of positions around a patient on a patient support. The accelerator is configured to produce a proton or ion beam having an energy level sufficient to reach any arbitrary target in the patient from positions within the range. The proton or ion beam passes essentially directly from the accelerator to the patient. In some examples, the synchrocyclotron has a superconducting electromagnetic structure that generates a field strength of at least 6 Tesla, produces a beam of particles having an energy level of at least 150 MeV, has a volume no larger than 4.5 cubic meters, and has a weight less than 30 Tons.
摘要:
Interposing a programmable path length of one or more materials into a particle beam modulates scattering angle and beam range in a predetermined manner to create a predetermined spread out Bragg peak at a predetermined range. Materials can be “low Z” and “high Z” materials that include fluids. A charged particle beam scatterer/range modulator can comprise a fluid reservoir having opposing walls in a particle beam path and a drive to adjust the distance between the walls of the fluid reservoir under control by a programmable controller. A “high Z” and, independently, a “low Z” reservoir, arranged in series, can be used. When used for radiation treatment, the beam can be monitored by measuring beam intensity, and the programmable controller can adjust the distance between the opposing walls of the “high Z” reservoir and, independently, the distance between the opposing walls of the “low Z” reservoir according to a predetermined relationship to integral beam intensity. Beam scattering and modulation can be done continuously and dynamically during a treatment in order to deposit dose in a target volume in a predetermined three dimensional distribution.
摘要:
A diaphragm cover apparatus and method for a sensor are disclosed. A sensor cover is located proximate to a base. A dimple can be located centrally within the cover, wherein the dimple comprises a component that is separate from the sensor cover and diaphragm. The dimple contacts a sense element of the sensor. Additionally, a foil can be adapted for use in blocking air permeation through the sensor diaphragm, when the sensor experiences pressure. An over mold diaphragm is generally located as part of the sensor cover. The dimple itself comprises a highly polished surface to reduce stress concentrators from contacting the sense element. The dimple can be formed from materials such as stainless steel, ceramic and the like to optimize the performance of the sensor.
摘要:
A system includes a patient support and an outer gantry on which an accelerator is mounted to enable the accelerator to move through a range of positions around a patient on the patient support. The accelerator is configured to produce a proton or ion beam having an energy level sufficient to reach a target in the patient. An inner gantry includes a robotic arm capable of directing an aperture for directing the proton or ion beam towards the target.
摘要:
Methods of manufacturing a three-dimensional, biodegradable, thermoset polymeric network composition having desirable degradation and mechanical properties, comprising a macromer component cross-linked with a monofunctional acrylate-containing component. The macromer component can comprise a diacrylate-containing component polymerized with an amine-containing component, wherein the molar ratio of the diacrylate-containing component to the amine-containing component is greater than or equal to 1.