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raditional digitizers for signal readout of PET detectors are based on commercial analog-to-digital converters (ADC). However, the cost and power consumption of an entire electronic readout system based on digitizers for a PET scanner are high. To address this problem, a soft-core ADC based on a field-programmable gate array (FPGA) was proposed. An FPGA-based ADC (FPGA-ADC) combines low loss and high performance. To achieve good performance, the FPGA-ADC requires three calibrations: time-to-digital converter (TDC) length calibration, TDC alignment calibration, and TDC-to-ADC calibration. A prototype front-end electronics based on FPGA-ADC was built to evaluate the performance of time-of-flight positron emission tomography (TOF PET) detectors. Each PET detector consists of a LYSO crystal single-ended coupled to a silicon photomultiplier (SiPM). The experimental results show that the full-width at half-maximum (FWHM) energy resolution for 511 keV gamma photons after saturation correction of the SiPM was 12.3 %. The FWHM coincidence timing resolution (CTR) of the TOF PET detector with the readout of the front-end electronic prototype is 385.2 ps. FPGA-ADC-based front-end electronics are very promising for multichannel, low-cost, highly integrated, and power-efficient readout electronic systems for radiation detector applications.

Background]In the decommissioning of nuclear facilities and emergency response to nuclear accidents, the existing decontamination materials mostly lack the function of real- monitoring of radioactive nuclides such as uranium, resulting in the decontamination process being difficult to control precisely and the decontamination effect being difficult to assessaneously. [Purpose] In view of the current material usage situation, this study prepared a strippable decontamination material with uranium colorimetric tracing function. This material undergo significant color changes during the process of adsorbing uranium contamination, thus realizing the visual monitoring of uranium contamination[Methods]. In this paper, the stress-strain, acid-base, wettability, and surface spreading degree of the decontaminant were tested, and the factors affecting the decontamination and colorimetric performance processes of the deaminant were discussed. The film-forming performance, decontamination efficiency, colorimetric sensitivity, and environmental stability of the material were systematically studied to verify its feasibility and in practical applications.

he technique of B-defined isochronous mass spectrometry (B-IMS), established at a storage ring, serves as a valuable tool for determining the masses of short-lived nuclei. In the previous B-IMS experiments, the effects of magnetic field drifts have to be corrected in order to improve the mass resolving power of B-IMS [Eur. Phys. J. A 59, 27 (2023)]. The correction procedures are complicated and require multiple reference ions with well-known masses in each injection, which may not be the cases in the measurements of exotic nuclei with tiny production yields. In this study, we propose a novel approach of B-IMS that requires only one reference ion for mass determination in an individual injection, avoiding the tedious and complicated correction procedures. This approach achieves the mass precision comparable to that of previous B-IMS results, and is approved to be suitable for future mass measurements of exotic nuclei with extremely low production yields.

Background: Driven by the wave of post-industrial transformation, cities worldwide are experiencing a structural shift from productive spaces to cultural consumption spaces. As an integral component of urban stock spaces, industrial heritage has increasingly become a focal point in urban regeneration and cultural revitalization, with its spatial and value transformations emerging as key research topics.Methods: This study takes Hechai 1972 Creative Park as a case, examining its spatial characteristics, cultural scenes, and media communication elements. Employing field interviews, data analysis, and multidimensional evaluation, and drawing on spatial production theory, scene theory, and spatial media theory, it analyzes the overall transformation logic and value of industrial heritage in its transition toward the cultural and creative industries, framed as driving forcesproduction logicscene constructionspatial mediation.Findings: In the cultural and tourism transformation of industrial heritage, spatial production drives and dominates the transformation logic; the construction of diverse oldnew scenes generates new urban cultural tensions; and digital communication fosters the mediated reproduction of space. The overall transformation path presents a spiral development process of spatial attribute transformationspatial productionscene constructionspatial mediation, reflecting a coupling mechanism of multiple types of spatial production that progress from spatial regeneration to cultural value enhancement and symbolic dissemination.Discussion: The case reveals several challenges, including the weak knowledge attributes and educational potential of space, insufficient depth in cultural scene construction, and underdeveloped social participation mechanisms with relatively singular governance actors. Policy and operational recommendations are proposed to strengthen historical education functions, enhance cultural embeddedness, and build co-governance mechanisms involving diverse stakeholders.

ardiovascular diseasesCVDand their risk factors are exerting an increasingly significant impact on public healthand the incidence rate of CVD continues to rise. The economic burden brought by CVD to residents and society is increasing, and it has become a major public health problem, and it is urgent to strengthen the government-led CVD prevention and control work. This article provides an interpretation of essentials from the newly published Annual Report on Cardiovascular Health and Diseases in China2024aiming to offer scientific evidence for CVD preventiontreatmentand the formulation of relevant policies.