Abstract: A method, computed tomography (CT) system and computer-readable medium for reconstructing an image volume of an object scanned in helical mode. An embodiment of the method includes determining discrete focal lengths within an imaging plane of the reconstructed field of view comprising the image volume; generating a circular scan sinogram(s) for the discrete focal lengths by interpolating the helical views; selecting within a backprojection operation a circular scan sonogram(s), for one or more image points within the imaging plane, over one or more circular views. The method then includes using the selected circular scan sinogram(s), in the backprojection of the image points point(s) over the circular views view(s) and performing a backprojection for all the image points over all the circular views to generate a reconstructed image of the object.

Abstract: Disclosed herein is a method of identifying a unidentified substance, comprising directing light from a light emitting source directly upon a stationary unidentified substance; collecting fluorescence from the unidentified substance in a detector; wherein the detector comprises a lock-in detection system; analyzing the fluorescence; and identifying the unidentified substance. Disclosed herein is a detection system comprising a light emitting source; a circuit board; wherein the trigger is operative to trigger a pulse of electrons from the circuit board to the light emitting source; a detector; and a central processing unit, wherein fluorescence generated from an unknown unidentified substance that is illuminated by light from the light emitting source is collected in the detector and analyzed in the central processing unit.

Abstract: Embodiments of the invention include a system for sensing homonuclear diatomic molecules, such as, for example, nitrogen. Other embodiments include a method for sensing homonuclear diatomic molecules. The system may include a light source, a hollow-core wave-guiding device that exhibits a low attenuation at predetermined operating optical frequencies and is in optical communication with the light source, a gas introduction system for introducing a gaseous medium between the light source and the hollow-core wave-guiding device, and a detector in optical communication with the hollow-core wave-guiding device.

Abstract: A system for detecting and counting individuals in a stationary or moving crowd based on a digital or digitized image captured from a single camera. Initial information is assumed based on a foot-to-head plane homology, where a geometric construct is developed to best enclose image features with a high probability of being an individual within a crowd. These geometric constructs are then subjected to further probabilistic analysis to determine individuals. The vector track of each individual is determined to validate the determination of a group of features as individuals, thereby compensating for occlusion of an individual within any given frame image. A virtual gate is then employed to count the individuals moving past the virtual gate. Also, by weighting portions of the individual, events near the gate can be predicted.

Abstract: An X-ray detection and inspection system is disclosed. The system includes an X-ray source configured to generate an interrogating X-ray beam, wherein the X-ray beam is directed towards a probe volume in a sample, one or more two-dimensional area detectors, wherein the one or more detectors are positioned at angles other than 90 degrees with respect to the direction of the interrogating beam and are configured to receive and detect non-circular conic sections of diffracted X rays from the probe volume, and an acquisition and analysis system configured to generate position and intensity data of the non-circular conic sections such that the corresponding mathematical equations of the conic sections could be generated, to identify one of a quasi-monochromatic or monochromatic XRD pattern from the non-circular conic sections, and to determine a position of the probe volume and at least two Bragg diffraction angles from said XRD pattern.

Abstract: A method of Raman detection for a portable, integrated spectrometer instrument includes directing Raman scattered photons by a sample to an avalanche photodiode (APD), the APD configured to generate an output signal responsive to the intensity of the Raman scattered photons incident thereon. The output signal of the APD is amplified and passed through a discriminator so as to reject at least one or more of amplifier noise and dark noise. A number of discrete output pulses within a set operational range of the discriminator is counted so as to determine a number of photons detected by the APD.

Abstract: A method of Raman detection for a portable, integrated spectrometer instrument includes directing Raman scattered photons by a sample to an avalanche photodiode (APD), the APD configured to generate an output signal responsive to the intensity of the Raman scattered photons incident thereon. The output signal of the APD is amplified and passed through a discriminator so as to reject at least one or more of amplifier noise and dark noise. A number of discrete output pulses within a set operational range of the discriminator is counted so as to determine a number of photons detected by the APD.

Abstract: An interface assembly for a sensor array is provided. The interface assembly may be made up of an integrated circuit package thermally coupled to the sensor array. The interface assembly may include a temperature control system for controlling the temperature of the sensor array. The temperature control system includes a temperature sensor for sensing a temperature variation of each sensor of the sensor array from an initial temperature beyond a predetermined threshold. A temperature controller is coupled to each temperature sensor and receives an output signal from the temperature sensor upon the sensor temperature variation exceeding the predetermined threshold. A temperature correction device is coupled to each temperature controller and causes the sensor temperature variation to fall within the predetermined threshold upon receiving a control signal from the temperature controller.

Abstract: A device for emission of electromagnetic radiation comprises a source of atomic particles and a collector disposed to receive atomic particles from the source. The collector comprises an emission medium, the medium comprising a crystal having a spatial dimension in the range from about 10 nanometers to about 50 micrometers, wherein the emission medium has the capability to generate opposing charge pairs upon absorption of atomic particles from the source and to emit electromagnetic radiation upon recombination of the pairs. The emission may be via spontaneous emission or, in certain embodiments, by stimulated emission. A laser assembly comprising this device, and methods for making the device are also presented herein.

Abstract: According to one embodiment, a micro-electrical mechanical system apparatus includes first and second mirrors that define a cavity. Moreover, a photonic band-gap structure coats a surface of at least one of the first or second mirrors to improve reflectivity. Another embodiment includes a third mirror, wherein the second and third mirrors form a second cavity. The spaces between the mirrors might comprise, for example, a pair of Fabry-Perot filter cavities for a spectrometer.

Abstract: A system and method for active MR tracking includes a magnetic resonance imaging (MRI) system having a plurality of gradient coils positioned about a bore of a magnet, an RF coil assembly positioned in the bore, and a pulse module. The MRI system also includes a polarization reversal switch controlled by the pulse module to transmit RF signals to the RF coil assembly coupled to the polarization reversal switch and an RF switch controlled by the pulse module to transmit the RF signals to the polarization reversal switch.

Abstract: An optofluidic device is provided. The device includes a cladding region having a first refractive index, and a channel defined by the cladding region such that the cladding region forms an inner surface or an interface of the channel. The channel is configured to house one or more of a liquid, a solid, a gas, a colloidal, or a suspension sample, wherein the sample has a second refractive index, where the channel is configured to guide radiation, and where the first refractive index is lower than the second refractive index.

Abstract: According to one embodiment, a micro-electrical mechanical system apparatus includes a bi-stable actuator and at least one movable Fabry-Perot filter cavity mirror coupled to the bi-stable actuator. The bi-stable actuator may be associated with a first latched position and a second latched position and may comprise, for example, a thermal device, an electrostatic device (e.g., a parallel plate or comb drive), or a magnetic device. According to some embodiments, a relationship between a voltage applied to an actuator of a Fabry-Perot filter and an amount of displacement associated with a movable mirror is substantially linear.

Abstract: A method of prioritizing messages on a Local Area Network comprises receiving a digitized incoming message, comparing a message signature of the incoming message with a stored priority message signature, passing non-priority messages to a standard Ethernet protocol stack for processing, storing priority messages temporarily, preventing priority messages from being processed in the standard Ethernet protocol stack, and handling priority messages using a simplified protocol stack designed to process a specific data packet type. This method may be performed by an Application Specific Integrated Circuit (ASIC) inserted between an Ethernet PHY layer and Ethernet MAC layer on a Network Interface Card of a host device. In particular, automated machinery control systems using the Ethernet protocol for networking are intended to benefit from the prioritizing method and implementation.

Abstract: A diagnostic imaging system includes a high frequency electromagnetic energy source that emits a beam of high frequency electromagnetic energy toward an object to be imaged. An energy discriminating (ED) detector receives high frequency electromagnetic energy emitted by the high frequency electromagnetic energy source. The ED detector includes a direct conversion layer dynamically operable in a photon counting mode in one view and in an integrating mode in another view and an indirect conversion layer. A data acquisition system (DAS) is operably connected to the ED detector and a computer operably connected to the DAS.

Abstract: A structured scintillator and a detection system employing structured scintillators. More specifically, a structured scintillator comprising a scintillator material having a plurality of isolated structures is disclosed. The structures may be conical in shape. The structures may be formed on a substantially transparent material layer which has been patterned to form a plurality of isolated regions. The structures may be formed on top of the isolated regions to provide isolated scintillator structures having space therebetween. The isolated regions and scintillator structures may be aligned with underlying detection devices.

Abstract: An anode assembly includes a rotatable hub having a rotation axis and having a cooling passage formed therethrough and a ferrofluid seal attached to the rotatable hub, the ferrofluid seal fluidically separating a first volume containing the target from a second volume. A target is attached to the rotatable hub, the target having a rotation axis coincident with the rotation axis of the rotatable hub and having a chamber formed therein fluidically coupled to the cooling passage, the target having a focal track material attached to an outer face of the target.