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The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 caused the widespread contamination of Fukushima Prefecture by radioactive cesium. The cesium radioisotopes are considered to have remained in the soil for seven years. We investigated this situation by analyzing soil from paddy fields in the area. We investigated the structure of soil particles using scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDS) and autoradiogram (ARG). We estimated the percentage of clay in the soil based on its composition, and then obtained the radioactivity of the cesium radioisotopes for each soil particle size as a function of penetration. The cesium radioisotopes were exponentially distributed in soil containing a large proportion of clay. Hence, we confirmed that the quantity of clay in the soil is a very important factor with respect to the possibility of the resumption of agriculture in the restricted area.

The LNS Superconducting Cyclotron, named “Ciclotrone Superconduttore” (CS), has been in operation for more than 20 years. A wide range of ion species from hydrogen to lead, with energy in the range 10 to 80 AMeV, have been delivered to users. The maximum beam power is limited to 100 W due to the beam dissipation on the electrostatic deflectors. To fulfil the demand of users aiming at studying rare processes in nuclear physics, an upgrade of the cyclotron is necessarily intended to increase the intensity of ion beams with mass lower than 40 a.m.u. up to a power 10 kW. This will be achieved by means of extraction by stripping. This solution needs to replace the cryostat including the superconducting coils. The present capability of the cyclotron will be maintained, i.e. all the ion species allowed by the operating diagram will be available, being extracted by electrostatic extraction. In addition to the high power beams for nuclear physics, it will be possible to produce medical radioisotopes like ${}^{211}\mathrm{\text{At}}$ using an internal target.

Radioisotopes are crucial in medical imaging for the diagnosis and monitoring of disease. The current status of radioisotope production is outlined and examples of their use are provided.

Particle accelerators were initially developed to address specific scientific research goals, yet they were used for practical applications, particularly medical applications, within a few years of their invention. The cyclotron's potential for producing beams for cancer therapy and medical radioisotope production was realized with the early Lawrence cyclotrons and has continued with their more technically advanced successors — synchrocyclotrons, sector-focused cyclotrons and superconducting cyclotrons. While a variety of other accelerator technologies were developed to achieve today's high energy particles, this article will chronicle the development of one type of accelerator — the cyclotron, and its medical applications. These medical and industrial applications eventually led to the commercial manufacture of both small and large cyclotrons and facilities specifically designed for applications other than scientific research.

Medical applications represent the vast majority of the uses for radiotracers. This review addresses how accelerators are employed for the production of high purity radionuclides that are used in basic biomedical research, as well as for clinical medicine both for diagnosing disease and for treatment.

Objective: To explore the method and quality control of ${}^{11}$C radiolabeled $l$-SPD ($l$-Stepholidine) and biodistribution of ${}^{11}$C-$l$-SPD in vivo.

Methods: (1) ${}^{11}$CO₂ was produced by CTI RDS III cyclotron, converted ${}^{11}$CO₂ to ${}^{11}$C–CH₃I by CH₃I die-block, and then converted it to ${}^{11}$C-Triflate–CH₄, imported ${}^{11}$C-Triflate–CH₄ to $l$-SPD which was dissolved in Dimethyl sulfoxide [(CH₃)₂SO], reacted at common temperature and then obtained the product. (2) Take the sample of organs in different times 5, 15, 30, 60, 90min after injecting ${}^{11}$C-$l$-SPD by vail in mice and measure the radioactive counts per minute (cpm), then the percent injection dose of wet tissue per gram (%ID/g) was calculated.

Results: (1) The synthesis time of ${}^{11}$C-$l$-SPD was 15 to 20min with chemical $\mathrm{\text{purity}}>90$%, and PH values $6.5\pm 0.3$, radiochemical $\mathrm{\text{purity}}>95$% in 2h. All quality criteria of ${}^{11}$C-$l$-SPD met the requirements of the positron radio-pharmaceuticals. (2) ${}^{11}$C-$l$-SPD was of the characteristic that metabolism was through the liver, and kidney was the main excretory organ, which was $1.323\pm 0.153$%ID/g at 5min and was decreasing gradually, which was $1.484\pm 0.350$ID/g in liver at 5min.

Conclusion: (1) ${}^{11}$C-$l$-SPD can be used to further study the animal or human. (2) ${}^{11}$C-$l$-SPD could quickly discharge and decrease to the low level from background of issues in vivo.

Medical applications represent the vast majority of the uses for radiotracers. This review addresses how accelerators are employed for the production of high purity radionuclides that are used in basic biomedical research, as well as for clinical medicine both for diagnosing disease and for treatment.

Particle accelerators were initially developed to address specific scientific research goals, yet they were used for practical applications, particularly medical applications, within a few years of their invention. The cyclotron's potential for producing beams for cancer therapy and medical radioisotope production was realized with the early Lawrence cyclotrons and has continued with their more technically advanced successors — synchrocyclotrons, sector-focused cyclotrons and superconducting cyclotrons. While a variety of other accelerator technologies were developed to achieve today's high energy particles, this article will chronicle the development of one type of accelerator — the cyclotron, and its medical applications. These medical and industrial applications eventually led to the commercial manufacture of both small and large cyclotrons and facilities specifically designed for applications other than scientific research.