We are using a novel position sensitive avalanche photodiode (PSAPD) for the construction of a high resolution positron emission tomography (PET) camera. Up to now most researchers working with PSAPDs have been using an Anger-like positioning algorithm involving the four corner readout signals of the PSAPD. This algorithm yields a significant non-linear spatial "pin-cushion" distortion in raw crystal positioning histograms. In this paper, we report an improved positioning algorithm, which combines two diagonal corner signals of the PSAPD followed by a 45° rotation to determine the X or Y position of the interaction. We present flood positioning histogram data generated with the old and new positioning algorithms using a 3 × 4 array of 2 × 2 × 3 mm and a 3 × 8 array of 1 × 1 × 3 mm of LSO crystals coupled to 8 × 8 mm PSAPDs. This new algorithm significantly reduces the pin-cushion distortion in raw flood histogram image.
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http://dx.doi.org/10.1109/TNS.2007.894129 | DOI Listing |
Genome Med
January 2025
Blizard Institute, Barts and The London Faculty of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, UK.
Background: Senescence classification is an acknowledged challenge within the field, as markers are cell-type and context dependent. Currently, multiple morphological and immunofluorescence markers are required. However, emerging scRNA-seq datasets have enabled an increased understanding of senescent cell heterogeneity.
View Article and Find Full Text PDFISA Trans
January 2025
School of Mechanical Engineering, Dongguan University of Technology, Dongguan 523015, China; School of Mechanical Engineering, Yanshan University, Qinhuangdao 066004, China. Electronic address:
Excavators, a type of human-operated construction machinery, suffer from poor hydraulic load braking stability, which seriously affects operator comfort. To address this challenge, this study investigates load braking laws through model analysis and designs an open-loop control algorithm called command reshaping, which can prolong the small-opening time of the main valve by segmentally adjusting the joystick command during load braking and then actively adjusting the key parameters reflecting the system's kinetic-potential energy state, thereby suppressing braking oscillations. The experimental results based on a 1.
View Article and Find Full Text PDFBMJ Open Ophthalmol
January 2025
Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China
Objective: We compared the protein structure and pathogenicity of clinically relevant variants of the gene with AlphaFold2 (AF2), Alpha Missense (AM), and ThermoMPNN for the first time.
Methods And Analysis: The sequences of clinically relevant Cog4 missense variants (one novel identified p.Y714F and three pre-existing p.
J Environ Manage
January 2025
School of Economics and Management, China University of Geosciences Beijing, Beijing, 100083, China.
Achieving the national climate target would depend on national actions. China has implemented important market mechanisms for a green and low-carbon energy transition, including the Renewable Portfolio Standard (RPS), the Tradable Green Certificate (TGC) market, the green power trading market, and so on. However, how to effectively integrate coupled TGC and green power trading to achieve a balance between maximizing economic benefits and environmental friendliness remains to be explored.
View Article and Find Full Text PDFBiomed Phys Eng Express
January 2025
Xi'an Jiaotong University, No.28 Xianning West Road, Xi'an, Shaanxi 710049, P.R. China, Xi'an, 710049, CHINA.
The optimal method for three-dimensional thermal imaging within cells involves collecting intracellular temperature responses while simultaneously obtaining corresponding 3D positional information. Current temperature measurement techniques based on the photothermal properties of quantum dots face several limitations, including high cytotoxicity and low fluorescence quantum yields. These issues affect the normal metabolic processes of tumor cells.
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