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Purpose: The purpose was to investigate the effects of short acquisition time on the image quality and the lesion detectability of oncological 18F-FDG total-body PET/CT. Methods: Nineteen oncological patients (6/13 women/men, age 65.6 ± 9.4 years) underwent total-body PET/CT on uEXPLORER scanner using 3D list mode. The administration of 18F-FDG was weight-based (4.4 MBq/kg). The acquisition time was 900 s, and PET data were reconstructed into 900-, 180-, 120-, 60-, 30-, and 18-s duration groups. The subjective PET image quality was scored using a 5-point scale (5, excellent; 1, poor) in 3 perspectives: overall quality, noise, and lesion conspicuity. The objective image quality was evaluated by SUVmax and standard deviation (SD) of the liver, SUVmax of the tumor, and tumor-to-background ratio (TBR). The lesion detectability was the percentage of identifiable lesions in the groups of 180 to 18 s using the group 900 s as reference. Results: Our results showed that sufficient and acceptable subjective image quality could be achieved with 60- and 30-s groups, and good image quality scores were given to 180- and 120-s groups without significant difference. For shortened acquisition time, SD was increased, while SUVmax of tumor and TBR remained unchanged. The lesion detectability was decreased with shorter acquisition time, but the detection performance could be maintained until the 60-s group compared with the 900-s group, although the image quality degraded. Conclusion: The total-body PET/CT can significantly shorten the acquisition time with maintained lesion detectability and image quality. [ABSTRACT FROM AUTHOR]

Iodine-modified ZnO with oxygen vacancies were synthesized by the solvothermal method. The crystal structure, morphology, optical properties and defects of as-prepared samples were characterized by XRD, SEM, DRS, XPS and ESR. The photocatalytic disinfection activity of I-modified ZnO in the dark and under visible light irradiation were investigated by the antibacterial drop-test method. The results showed that the iodine mainly exists in the form of I in the ZnO. The modified iodine increases the numbers of oxygen vacancies of ZnO as the amount of iodine increases. In addition, the I-ZnO exhibits much higher antibacterial activity than that of pure ZnO and was stable during the photocatalytic process. The enhanced antibacterial activity of I-ZnO is attributed to the co-operation of the oxygen vacancies and the iodine which promotes the separation of photo-generated carriers and subsequently produces more ROS (reactive oxygen species). Graphical Abstract: [ABSTRACT FROM AUTHOR]