Abstract: Systems and methods for correcting output signals from non-linear photosensors, specifically silicon photomultipliers (SiPMs). SiPMs are used in a PET detector to readout light emissions from LSO scintillator crystals. The non-linear output of the SiPM can distort and compress the energy spectrum which is crucial in PET imaging. The non-linearity effect for inter-crystal scattered events can place an energy event outside of the PET detector energy window, resulting in a rejected event. Systems and methods to correct the SiPM non-linearity for inter-crystal scattered events, so as to be able to obtain the proper energy event and produce an accurate medical image, are disclosed.

Abstract: An apparatus and method to decrease light saturation in a photosensor array and increase detection efficiency uses a light distribution profile from a scintillator-photodetector geometry to configure the photosensor array to have a non-uniform sensor cell pattern, with varying cell density and/or varying cell size and shape. A solid-state photosensor such as a SiPM sensor having such a non-uniform cell structure realizes improved energy resolution, higher efficiency and increased signal linearity. In addition the non-uniform sensor cell array can have improved timing resolution due to improvements in statistical fluctuations. A particular embodiment for such photosensors is in PET medical imaging.

Abstract: A system and method are provided for determining the onset of gamma interactions for positron emission tomography (PET) imaging more accurately than with existing techniques. The timing of a sequence of primary trigger events is obtained and used to determine a weighted combination, which mixes the timing information from the various primary trigger events to compute an overall event trigger timing with improved time resolution. Numerical simulations demonstrate that the invention improves time resolution by approximately 10% over state-of-the-art methods. This improved time resolution directly benefits the imaging performance of the PET scanner, especially in time-of-flight (TOF) mode, where a high time resolution directly translates to a reduction in image noise at the same dose—or, alternatively, a reduction of dose to the patient or scan time for the same image quality.

Abstract: Analytical cartridges, systems and methods of processing a sample for analysis using capillary flows. Vertical gradient sample filtration provides filtrate to an incubation chamber for a time controlled by a flow modulator at the outlet of the incubation chamber. The flow modulator can include a serpentine capillary flow path without side walls. Incubated filtrate can flow from the incubation chamber to a detection channel after a predetermined time. The detection chamber can include one or more analytical regions in a porous substrate for detection of two or more analytes on the same cartridge from the same sample.

Abstract: A catalyst for olefin polymerization and method of preparing the same are disclosed.

Abstract: A method of optimising a processing system comprising a plurality of apparatuses includes defining a system model indicative of a predetermined range of apparatus options within a processing system, constraints indicative of feasible interconnections between each apparatus and another apparatus, and parameters indicative of performance criteria associated with each apparatus. The system model is analysed with respect to predetermined criteria to determine a preferred arrangement of apparatuses within the processing system. A parameter relating to at least one apparatus is indicative of the availability and/or the reliability of the apparatus expressed as a function of time.

Abstract: The present invention discloses 23-hydroxyl-betulinic acid derivatives, including 3-oxo-23-hydroxyl-betulinic acid, 3-oxo-23-hydroxyl-dihydrobetulinic acid, and 23-hydroxyl-dihydrobetulinic acid. The present invention also discloses the preparation methods thereof and medical applications as anti-tumor and anti-HIV agents.

Abstract: Gel nanoparticles for encapsulating and delivering a pharmaceutical compound to a patient. The nanoparticles are formed from N-trimethyl chitosan and polysialic acid, preferably in the presence of sodium tripolyphosphate. A ratio of polysialic acid to N-trimethyl chitosan of about 0.5 to 1 produces nanoparticles having diameter of about 100 nm (plus or minus 25 nm) and a zero potential above 30 milivolts that can stability contain a pharmaceutical compound, such as methotrexate, for delivery to a patient.

Abstract: A temperature controller for adjusting temperature includes a substrate side contact portion formed on a surface on one side of a circuit substrate for processing an input signal. The substrate side contact portion is configured to be brought into contact with a cable device.

Abstract: Analytical cartridges, systems and methods of processing a sample for analysis using capillary flows. Vertical gradient sample filtration provides filtrate to an incubation chamber for a time controlled by a flow modulator at the outlet of the incubation chamber. The flow modulator can include a serpentine capillary flow path without side walls. Incubated filtrate can flow from the incubation chamber to a detection channel after a predetermined time. The detection chamber can include one or more analytical regions in a porous substrate for detection of two or more analytes on the same cartridge from the same sample.

Abstract: Signals generated by radiation sensors can be encoded to reduce the number of cables needed to transport information from a nuclear imaging apparatus to a processor for reconstruction. For example, signals from 16 radiation sensors can be encoded into three signals: T (top), L (left), and E (energy). This method of encoding signals can be capable of substantially reducing the number of signals, thereby reducing costs. In addition, reducing the number of signals could improve system timing performance by eliminating cable time-skew and facilitate the filter design by downgrading the circuit accuracy requirements such as group-delay error and filter signal skews.

Abstract: The present invention is a photodetector including improved photosensors configured of an array of small (sub-millimeter) high-density avalanche photodiode cells utilized to readout a single scintillator. Each photosensor comprises a plurality of avalanche photodiodes cells arranged in an (n×n) array of avalanche photodiode cells (where, n>1) that are coupled to a single scintillation crystal. The overall (n×n) array area as the photosensor is the same as the area of a face of the scintillator and each avalanche photodiode cell has a surface area that is not greater than one square millimeter. The photosensor is also configured to facilitate reading the output of each avalanche photodiode cell in the array. By reading out each small avalanche photodiode cell independently, the noise and capacitance are minimized and thereby provide a more accurate determination of energy and timing.

Abstract: An optical mask positioned on a scintillator array. The optical mask includes a reflective layer. One or more windows can be positioned on the surface of optical mask.

Abstract: A method and algorithm are disclosed that can be used to determine if an electrical fault exists within a protection zone defined as in the area between specific current transformers. (CTs). Currents from CTs are brought into a microprocessor (or other device) that converts the analog currents into digital quantities. The current quantities are summed both vectorially and arithmetically by the microprocessor. The mathematical derivative of the vector and the arithmetic sums are compared in order to determine if an electrical fault exists within the protection zone. An electrical trip signal is generated by the microprocessor if the fault is deemed to be in the protection zone.

Abstract: As file systems reach the petabytes scale, users and administrators are increasingly interested in acquiring high-level analytical information for file management and analysis. Two particularly important tasks are the processing of aggregate and top-k queries which, unfortunately, cannot be quickly answered by hierarchical file systems such as ext3 and NTFS. Existing pre-processing based solutions, e.g., file system crawling and index building, consume a significant amount of time and space (for generating and maintaining the indexes) which in many cases cannot be justified by the infrequent usage of such solutions. User interests can often be sufficiently satisfied by approximate (i.e., statistically accurate) answers. A just-in-time sampling-based system can, after consuming a small number of disk accesses, produce extremely accurate answers for a broad class of aggregate and top-k queries over a file system without the requirement of any prior knowledge. The system is efficient, accurate and scalable.

Abstract: The present invention is a photodetector including improved photosensors configured of an array of small (sub-millimeter) high-density avalanche photodiode cells utilized to readout a single scintillator. Each photosensor comprises a plurality of avalanche photodiodes cells arranged in an (n×n) array of avalanche photodiode cells (where, n>1) that are coupled to a single scintillation crystal. The overall (n×n) array area as the photosensor is the same as the area of a face of the scintillator and each avalanche photodiode cell has a surface area that is not greater than one square millimeter. The photosensor is also configured to facilitate reading the output of each avalanche photodiode cell in the array. By reading out each small avalanche photodiode cell independently, the noise and capacitance are minimized and thereby provide a more accurate determination of energy and timing.

Abstract: A catalyst for olefin polymerization and method of preparing the same are disclosed.

Abstract: A method of modifying a substrate for deposition of charged particles thereon, the method comprising the steps of: providing a substrate that is incapable of bonding to a polyelectrolyte coating that has a charge that is opposite to the charge of the particles that are to be deposited thereon; modifying the surface of the substrate to provide a layer of silicon thereon or therein; and coating the silicon layered surface of the substrate with the polyelectrolyte coating, the polyelectrolyte coating containing functional groups that are capable of forming bonds with said silicon layer and wherein said polyelectrolyte coating enables a substantially even distribution of said charged particles to be deposited thereon.

Abstract: The present invention is a Silicon PhotoMulitplier comprising a plurality of photon detection cell clusters each comprising a plurality of avalanche photodiodes connected in parallel, so that the output of each avalanche photodiode is summed together and applied to a cell cluster output. Each of the plurality of cell cluster outputs is connected to one of a plurality of cluster readout circuits, each of which includes an analog to digital converter that converts an analog representation of the total energy received by a photon detection cell cluster to a digital energy signal. A SiPM Pixel reader circuit is connected to the plurality of cluster readout circuits and configured to generate an overall pixel output by digital processing the plurality of digital energy signals received from the plurality of photon detection cell clusters by way of the plurality of cluster readout circuits.

Abstract: The catalyst for olefin polymerization contains three components A, B and C. The component A is a solid catalyst containing titanium, magnesium, chlorine element and an internal electron donor, the internal electron donor consists of 1,4-diether [2,2?-dialkoxy-1,1?-biphenyl, 2,2?-dialkoxy-1,1?-binaphthalene, 10,10?-dialkoxy-9,9-biphenanthrene]and organic acid ester or 1,3-diether [9,9-bis(methoxymethyl)fluorine, 2,2-dialky 1-1,3-dimethoxypropane]; the component B is an organoaluminum compound; the component C is external electron donor-organic silicon compound or the 1,4 aromatic diether. The catalyst has high catalytic activity, and can be adjusted in the range from 40,000 to 150,000 gPP/gCat when used in propylene polymerization. The polymer made therefrom has isotactivity of 80 to 99 percent and the molecular weight distribution can be adjusted in a wide range. The invention provides a novel method for preparing the 1,4 aromatic diether.