heavy ion beam
Recently Published Documents


TOTAL DOCUMENTS

664
(FIVE YEARS 56)

H-INDEX

31
(FIVE YEARS 4)

CYTOLOGIA ◽  
2021 ◽  
Vol 86 (4) ◽  
pp. 283-289
Author(s):  
Tsuyoshi Takeshita ◽  
Kaori Takita ◽  
Kotaro Ishii ◽  
Yusuke Kazama ◽  
Tomoko Abe ◽  
...  

CYTOLOGIA ◽  
2021 ◽  
Vol 86 (4) ◽  
pp. 291-295
Author(s):  
Yoichi Sato ◽  
Tomonari Hirano ◽  
Yoriko Hayashi ◽  
Nobuhisa Fukunishi ◽  
Tomoko Abe ◽  
...  

CYTOLOGIA ◽  
2021 ◽  
Vol 86 (4) ◽  
pp. 273-274
Author(s):  
Kotaro Ishii ◽  
Shigeyuki Kawano ◽  
Tomoko Abe

2021 ◽  
Vol 9 ◽  
Author(s):  
Fuquan Zhang ◽  
Junyu Zhang ◽  
Yan Lu ◽  
Yixiangzi Sheng ◽  
Yun Sun ◽  
...  

Purpose: The radioactivity induced by proton and heavy ion beam belongs to the ultra-low-activity (ULA). Therefore, the radioactivity and space range of commercial off-line positron emission tomography (PET) acquisition based on ULA should be evaluated accurately to guarantee the reliability of clinical verification. The purpose of this study is to quantify the radioactivity and space range of off-line PET acquisition by simulating the ULA triggered by proton and heavy ion beam.Methods: PET equipment validation phantom and low activity 18F-FDG were used to simulate the ULA with radioactivity of 11.1–1480 Bq/mL. The radioactivity of ULA was evaluated by comparing the radioactivity in the images with the values calculated from the decay function with a radioactivity error tolerance of 5%. The space range of ULA was evaluated by comparing the width of the R50 analyzed activity distribution curve with the actual width of the container with a space range error tolerance of 4 mm.Results: When radioactivity of ULA was >148 Bq/mL, the radioactivity error was <5%. When radioactivity of ULA was >30 Bq/mL, the space range error was below 4 mm.Conclusions: Off-line PET can be used to quantify the radioactivity of proton and heavy ion beam when the ULA exceeds 148 Bq/mL, both in radioactivity and in space range.


2021 ◽  
Vol 173 ◽  
pp. 112845
Author(s):  
H.R. Fan ◽  
T. Ido ◽  
A.D. Liu ◽  
Min Xu ◽  
Z.Y. Liu ◽  
...  

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Xiaoyun Ma ◽  
Mengling Zhang ◽  
Wanbin Meng ◽  
Xiaoli Lu ◽  
Ziheng Wang ◽  
...  

Background. The dose distribution of heavy ions at the edge of the target region will have a steep decay during radiotherapy, which can better protect the surrounding organs at risk. Objective. To analyze the dose decay gradient at the back edge of the target region during heavy ion radiotherapy. Methods. Treatment planning system (TPS) was employed to analyze the dose decay at the edge of the beam under different incident modes and multiple dose segmentation conditions during fixed beam irradiation. The dose decay data of each plan was collected based on the position where the rear edge of the beam began to fall rapidly. Uniform scanning mode was selected in heavy ion TPS. Dose decay curves under different beam setup modes were drawn and compared. Results. The dose decay data analysis showed that in the case of single beam irradiation, the posterior edge of the beam was 5 mm away, and the posterior dose could drop to about 20%. While irradiation in opposite direction, the posterior edge of the beam was 5 mm away, and the dose could drop to about 50%. In orthogonal irradiation of two beams, the posterior edge of the beam could drop to about 30-38% in a distance of 5 mm. Through the data analysis in the TPS, the sharpness of the dose at the back edge of the heavy ion beam is better than that at the lateral edge, but the generated X-ray contamination cannot be ignored. Conclusions. The effect of uneven CT value on the dose decay of heavy ion beam should also be considered in clinical treatment.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yan Du ◽  
Shanwei Luo ◽  
Jian Zhao ◽  
Zhuo Feng ◽  
Xia Chen ◽  
...  

Abstract Background Flower longevity is closely related to pollen dispersal and reproductive success in all plants, as well as the commercial value of ornamental plants. Mutants that display variation in flower longevity are useful tools for understanding the mechanisms underlying this trait. Heavy-ion beam irradiation has great potential to improve flower shapes and colors; however, few studies are available on the mutation of flower senescence in leguminous plants. Results A mutant (C416) exhibiting blossom duration eight times longer than that of the wild type (WT) was isolated in Lotus japonicus derived from carbon ion beam irradiation. Genetic assays supported that the delayed flower senescence of C416 was a dominant trait controlled by a single gene, which was located between 4,616,611 Mb and 5,331,876 Mb on chromosome III. By using a sorting strategy of multi-sample parallel genome sequencing, candidate genes were narrowed to the gene CUFF.40834, which exhibited high identity to ethylene receptor 1 in other model plants. A physiological assay demonstrated that C416 was insensitive to ethylene precursor. Furthermore, the dynamic changes of phytohormone regulatory network in petals at different developmental stages was compared by using RNA-seq. In brief, the ethylene, jasmonic acid (JA), and salicylic acid (SA) signaling pathways were negatively regulated in C416, whereas the brassinosteroid (BR) and cytokinin signaling pathways were positively regulated, and auxin exhibited dual effects on flower senescence in Lotus japonicus. The abscisic acid (ABA) signaling pathway is positively regulated in C416. Conclusion So far, C416 might be the first reported mutant carrying a mutation in an endogenous ethylene-related gene in Lotus japonicus, rather than through the introduction of exogenous genes by transgenic techniques. A schematic of the flower senescence of Lotus japonicus from the perspective of the phytohormone regulatory network was provided based on transcriptome profiling of petals at different developmental stages. This study is informative for elucidating the molecular mechanism of delayed flower senescence in C416, and lays a foundation for candidate flower senescence gene identification in Lotus japonicus. It also provides another perspective for the improvement of flower longevity in legume plants by heavy-ion beam.


2021 ◽  
pp. 131153
Author(s):  
Sourav Bhakta ◽  
Indra Sulania ◽  
S. Ojha ◽  
D. Kanjilal ◽  
Pratap K. Sahoo

2021 ◽  
Vol 22 (8) ◽  
Author(s):  
Andi Muliarni Okasa ◽  
Rinaldi Sjahril ◽  
Muhammad Riadi ◽  
Meta Mahendradatta ◽  
Tadashi Sato ◽  
...  

Abstract. Okasa AM, Sjahril R, Riadi M, Mahendradatta M, Sato T, Toriyama K, Ishii K, Hayashi Y, Abe T. 2021. Evaluation of Toraja (Indonesia) local aromatic rice mutant developed using heavy-ion beam irradiation. Biodiversitas 22: 3474-3481. The aromatic local Toraja rice "Pare Bau" has a good grain quality and aroma. However, it has some disadvantages, including a late heading and low yield for a modern farming system. This study aims to evaluate and select early heading as well as high yield mutant lines induced by heavy-ion beam irradiation. Furthermore, dry seeds of Pare Bau were irradiated with Argon-ion (300 keV/?m) and Carbon-ion (30 keV/?m) at RI-beam factory, RIKEN Nishina Center, Japan. The germination percentages of the M1 seeds were 49% for Pare Bau irradiated with Argon-ion (PB-A), 53% for Pare Bau irradiated with Carbon-ion (PB-C), and 70% for the Control. The 13 PB-A and 13 PB-C M1 plants were selected, and the seeds were sampled in the paddy field of Hasanuddin University (20 m asl.), Makassar. During the following planting season, the M2 generation plant was examined in Enrekang District (650 m asl.), South Sulawesi, Indonesia. Based on the early heading and a larger number of panicles, the 18 PB-A and one PB-C M3 line were selected from a total of 404 M2 survival plants. The selected lines and control were grouped into seven clusters based on the quantitative phenotypic traits, indicating the existence of genetic variability. The plant yield was significantly correlated with plant height, the number of tillers, the number of panicles, as well as grain weight per panicle, which showed that these traits are good criteria for selection.


Sign in / Sign up

Export Citation Format

Share Document