• Mass Spectrometry Letters
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• v.7 no.2
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• pp.31-40
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• 2016

The analysis of nuclear materials and environmental samples is an important issue in nuclear safeguards and nuclear forensics. An analysis technique for safeguard samples has been developed for the detection of undeclared nuclear activities and verification of declared nuclear activities, while nuclear forensics has been developed to trace the origins and intended use of illicitly trafficked nuclear or radioactive materials. In these two analytical techniques, mass spectrometry has played an important role in determining the isotope ratio of various nuclides, contents of trace elements, and production dates. These two techniques typically use similar analytical instruments, but the analytical procedure and the interpretation of analytical results differ depending on the analytical purpose. The isotopic ratio of the samples is considered the most important result in an environmental sample analysis, while age dating and impurity analysis may also be important for nuclear forensics. In this review, important aspects of these techniques are compared and the role of mass spectrometry, along with recent progress in related technologies, are discussed.

• Journal of the Korean Society of Costume
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• v.55 no.8 s.99
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• pp.73-84
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• 2005

Collections in the buddhist statue owned by Dr. Jong-Hm Baik(白宗欽) included 3 ancient documents and 2 wooden cylinders that showed a clear historical order. The temple and buddhist statue that these objects were belonged to were not known, however, according to the document, it could be inferred as Chunsukwaneumsang(천수관음상) created in 1322 and reformed in 1614 from the list of donator for the statue. Inside a wooden cylinder, a bundle of ivory, yellow, green, orange, and dark brown fabrics that were folded up and tided up with 5 different colored thread strands and aromatic trees and rice plant was placed on the bottom. All the fabrics were silk. Three thread strands were silk. The white and blue strands were cotton fibers as a result of analysis of IR spectrum and the microscope. According to a radioactive carbon isotope dating by accelerator mass spectroscopy, years before present was 160$\pm$40, and cablibrated ages were 1680-1890 (79.3$\%$), 1910-1960(16.1$\%$) in 95.4$\%$ probability. Accordingly, the fabrics in the buddhist statue proved to be reformed in 1614 not the original ones in 1322.

• Advances in pediatric surgery
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• v.2 no.2
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• pp.133-137
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• 1996

A 17 month-old girl presented in the pediatric clinic on November 27th, 1990 with a neck mass. The mass was 2 cm in diameter, firm in consistency and movable on the upper pole of the thyroid cartilage in the midline. The technetium thyroid scan showed a hot reactivity at the compatible site of the mass, but no other radioactivity in either site of the normal thyroid positions. At her second visit on January 23th, 1996, the mass had enlarged up to 3.5cm in diameter in the same location of the neck. The follow up thyroid scan revealed a walnut sized, snowman-like radioactivity. One of the snowman-like double images seemed to be a lingual ectopic thyroid and the other a midline ectopic thyroid remnant in the infrahyoid level. This interpretation was supported by the computed tomography of the neck, which showed a ligual mass in the foramen cecum area and an another mass in the anterior comis-sure of the larynx in the mildline. Thyroid function test was normal except a slightly increased TSH. As a result of this changing pattern of thyroid radioactive images, a case of a lingual thyroid as well as another midline ectopic thyroid tissue at the infrahyoid level is reported.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.184-188
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• 2009

Identification of differently expressed genes under specific tissues and/or environments provides insights into the nature and underlying mechanisms of cellular processes. Although cDNA-AFLP (Amplified Fragment Length Polymorphism) is a powerful method for analyzing differentially expressed genes, its use has been limited to the requirement of radioactive isotope use and the difficulty of isolating the bands of interest from a gel. Here, we describe a modified method for cDNA-AFLP that uses a fluorescence dye for detection and isolation of bands directly from a small size polyacrylamide gel. This method involves three steps: (i) preparation of cDNA templates, (ii) PCR amplification and differential display, and (iii) identification of differentially expressed genes. To demonstrate its utility and efficiency, differentially expressed genes during vegetative growth and appressorial development of Magnaporthe oryzae were analyzed. This method could be applied to compare gene expression profiles in a diverse array of organisms.

• Journal of Radiation Protection and Research
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• v.9 no.2
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• pp.112-117
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• 1984

A lot of radioisotopes are applied to medical fields. It's very important to measure the activities on airborne radioiodine discharged in air from $Na^{131}I$ solutions and from patients treated with radioiodine. Also surface decontamination is another one important problem to be completly solved in the isotope laboratory where there is always the possibility of radiation contamination. The Authors measured the activities on airborne radioiodine with RI collector and scintillation counter. 1. The mean accumulative activity of airborne radioiodine discharged into air from $Na^{131}I$ solution was measured as $1.3{\times}10^{-3}/hr$ rate, and the maximum value was $1.8{\times}10^{-3}/hr$. 2. Radioactivity rate per hour of airborne iodine discharged into air from patients treated with $Na^{131}I$ was measured as $6.2{\times}10^{-5}/hr$ at 8 hour after administration of radioiodine and decreased into $2{\times}10^{-6}/hr$ after 24 hour. 3. Metalic surfaces such as stainless steel or aluminum are decontaminated 5 to 6 times more rapidly than wood and concrete surfaces. 4. Decontamination with wet wiping with detergent was 9 to 10 times more rapidly than dry wiping method, but dry wiping was useful for the first step to prevent spreading and flowing from liquid radioactive materials.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.449-457
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• 2012

The purpose of this study is to investigate the relationship between radiation origin and health professionals, and to reduce exposed dose of radiation through efficient management. Increasing exposed dose of radiation to health professionals are caused by the increase of PET/CT use and a radioactive isotope. Hence, in this study, space dose from each origin of radiation generating was analyzed and the use of personnel protective clothing and shields was compared. As a result of this study, we confirmed that the exposed dose of radiation was much higher in case of wearing personnel protective clothing(0.5 mm pb) than no wearing personnel protective clothing under high energy gamma radiation(511 keV) of the position emitter($^{18}F$).

• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.483-488
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• 2001

A patient diagnosed as cellulitis by bone scan was taken the therapeutic intervention of Oriental medicine for 35 days. Cellulitis is characterized by acute purulence inflammation deeply diffused throughout epidermal connective tissue to subcutaneous adipose tissue. This patient presented a finding of soft tissue radioactive isotope uptake increase on bone scan of both foot and ankle. Cellulitis belongs to the category of ong(癰) in Oriental medicine. During therapeutic intervention, 3 herbal prescriptions were applied. Yeonkyopedok-san was applied for high fever and severe chilling on acute stage. After the application of Yeonkyopedok-san and Sunbangwhalmyong-eum, clinical symptoms improved with changes of CRP($112{\rightarro}12),\;WBC(13{\rightarro}8.8),\;ESR(65{\rightarro}46$). After the application of Chungpesagan-tang, clinical symptoms improved with changes of $CRP(12{\rightarro}3),\;WBC(8.8{\rightarro}5),\;ESR(46{\rightarro}13$).

• Journal of Radiation Industry
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• v.11 no.1
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• pp.33-38
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• 2017

RI-Biomics technology is advanced convergence technologies that can be measured in real time and track in vivo behavior and metabolism of substances using characteristics of the radioactive isotope. Its application fields are increasing such as drug development, agriculture, development of new materials and their utilization, etc. In addition, according to domestic and international developments and changes in the RI-Biomics environment, RI-Biomics professionals are needed to train continuously. To develop systematic human resources basement and competency-based curriculum, we perform competency modeling of pedagogical perspective to targeted at high-performance on RI-Biomics. Furthermore, we redefine the competency model and verified by industry experts with focus group interviews. In the result, two general competencies and three professional competencies were extracted by interview. Each competencies are organized six sub-competencies and nine sub-competencies. In the finial steps, the same procedures were repeated to obtain the consensus of experts on derived competencies and behavioral objectives. The results of the study are applicable to enhance human resource management and to develop the curriculum for RI-Biomics expert training. It is expected to be used as reference material of long term-planning for RI-Biomics professional.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3398-3402
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• 2022

We fabricated a 15 m long position-sensitive plastic scintillation optical fiber (PSOF) detector consisting of a PSOF, two photomultiplier tubes, four fast amplifiers, and a digitizer. A single PSOF was used as a sensing part to estimate the gamma-ray source position, and ¹³⁷Cs, an uncollimated solid-disk-type radioactive isotope, was used as a gamma-ray emitter. To improve the sensitivity, accuracy, and measurement time of a PSOF detector compared to those of previous studies, the performance of the amplifier was optimized, and the digital signal processing (DSP) was newly designed in this study. Moreover, we could measure very low dose rates of gamma-rays with high sensitivity and accuracy in a very short time using our proposed PSOF detector. The results of this study indicate that it is possible to accurately and quickly locate the position of a very low dose rate gamma-ray source in a wide range of contaminated areas using the proposed position-sensitive PSOF detector.

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3692-3699
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• 2023

The Rare isotope Accelerator complex for ON-line experiments in Korea houses several accelerator complexes. Among them, the µSR facility will be initially equipped with a 600 MeV and 100 kW proton beam to generate surface muons, and will be upgraded to 400 kW with the same energy. Accelerated proton beams lose approximately 20% of the power at the target, and the remaining power is concentrated in the beam direction. Therefore, to ensure safe operation of the facility, concentrated protons must be distributed and absorbed at the beam dump. Additionally, effective dose levels must be lower than the legal standard, and the beam dumps used at 100 kW should be reused at 400 kW to minimize the generation of radioactive waste. In this study, we introduce a tailored method for designing beam dumps based on the characteristics of the µSR facility. To optimize the geometry, the absorbed power and effective dose were calculated using the MCNP6 code. The temperature and stress were determined using the ANSYS Mechanical code. Thus, the beam dump design consists of six structures when operated at 100 kW, and a 400 kW beam dump consisting of 24 structures was developed by reusing the 100 kW beam dump.