• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.147-159
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• 2024

Plutonium-238 has always been considered as the one of the promising radioisotopes for space nuclear power supply, which has long half-life, low radiation protection level, high power density, and stable fuel form at high temperatures. The industrial-scale production of ²³⁸Pu mainly depends on irradiating solid ²³⁷NpO₂ target in high flux reactors, however the production process faces problems such as large fission loss and high requirements for product quality control. In this paper, a conceptual design study of producing ²³⁸Pu in a multi-purpose high flux reactor was evaluated and analyzed, which includes a sensitivity analysis on ²³⁸Pu production and a further study on the irradiation scheme. It demonstrated that the target structure and its location in the reactor, as well as the operation scheme has an impact on ²³⁸Pu amount and product quality. Furthermore, the production efficiency could be improved by optimizing target material concentration, target locations in the core and reflector. This work provides technical support for irradiation production of ²³⁸Pu in high flux reactors.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.174-182
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• 2024

In patients with multiple missing molars, wear patterns or displacement of anterior teeth, collapsed occlusal plane, and reduction in vertical dimension may occur. Particularly, in case of a few remaining teeth on one side, a removable partial denture has biomechanical disadvantage. For this reason, an implant-assisted removable partial denture with a few implant surveyed crowns can be an alternative. In this case, due to the right mandibular posterior teeth loss, the anterior teeth were severely worn and the occlusal plane was collapsed. With minimal increasing vertical dimension, oral rehabilitation was performed using a maxillary fixed prosthesis and mandibular implant-assisted removable partial denture. As a result, functional and aesthetic clinical outcomes were obtained.

• Journal of Chest Surgery
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• v.57 no.4
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• pp.329-338
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• 2024

Background: Video-assisted thoracoscopic surgery (VATS) is recognized as a safe and effective treatment modality for early-stage lung cancer and anterior mediastinal masses. Recently, novel articulating instruments have been developed and introduced to endoscopic surgery. Here, we share our early experiences with VATS major pulmonary resection and thymectomy performed using ArtiSential articulating instruments. Methods: At the Seoul Metropolitan Government-Seoul National University Boramae Medical Center, 500 patients underwent VATS pulmonary resection between July 2020 and April 2023, while 43 patients underwent VATS thymectomy between January 2020 and April 2023. After exclusion, 224 patients were enrolled for VATS major pulmonary resection, and 38 were enrolled for VATS thymectomy. ArtiSential forceps were utilized in 35 of the 224 patients undergoing pulmonary resection and in 12 of the 38 individuals undergoing thymectomy. Early clinical outcomes were retrospectively analyzed. Results: No significant differences were observed in sex, age, surgical approach, operation time, histological diagnosis, or additional procedures between the patients who underwent surgery using novel articulating instruments and the group treated with conventional endoscopic instruments for both VATS major pulmonary resection and thymectomy. However, the use of the novel articulating endoscopic forceps was associated with a significantly larger number of dissected lymph nodes (p=0.028) and lower estimated blood loss (p=0.009) in VATS major pulmonary resection. Conclusion: Major pulmonary resection and thymectomy via VATS using ArtiSential forceps were found to be safe and effective, with early clinical outcomes comparable to established methods. Further research into long-term clinical outcomes and cost-effectiveness is warranted.

• Hip & pelvis
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• v.34 no.2
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• pp.69-78
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• 2022

Fragility fractures of the pelvis (FFP) and fragility fractures of the sacrum (FFS), which are emerging in the geriatric population, exhibit characteristics that differ from those of pelvic ring disruptions occurring in the younger population. Treatment of FFP/FFS by a multidisciplinary team can be helpful in reducing morbidity and mortality with the goal of reducing pain, regaining early mobility, and restoring independence for activities of daily living. Conservative treatment, including bed rest, pain therapy, and mobilization as tolerated, is indicated for treatment of FFP type I and type II as loss of stability is limited with these fractures. Operative treatment is indicated for FFP type II when conservative treatment has failed and for FFP type III and type IV, which are displaced fractures associated with intense pain and increased instability. Minimally invasive stabilization techniques, such as percutaneous fixation, are favored over open reduction internal fixation. There is little evidence regarding outcomes of patients with FFP/FFS and more literature is needed for determination of optimal management. The aim of this article is to provide a concise review of the current literature and a discussion of the latest recommendations for orthopedic treatment and management of FFP/FFS.

• Research in Plant Disease
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• v.30 no.3
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• pp.268-277
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• 2024

Erwinia pyrifoliae is a gram-negative bacterial pathogen that commonly causes black shoot blight in pear and apple tree. Although the pathogenicity of this bacterial species is very similar to E. amylovora, there is no specific explanation of its pathogenic genes and mechanisms. In this study, our investigation into E. pyrifoliae pathogenicity involved generating seven YKB12327 mutant strains using Tn5 transposon mutagenesis. Observations revealed weakened growth rate and loss of pathogenicity in these mutants. Whole-genome sequencing and alignment analysis identified transposon insertions within the coding sequences of five strains and in the intergenic region of two strains. Annotation analysis elucidated genes directly or indirectly associated with pathogenicity. Notably, mutant strain MT16 displayed a transposon insertion mutation in the cyclic-di-GMP phosphodiesterase (pdeF) gene, a key player in bacterial signaling, governing microbial behavior and adaptation to environmental changes. Our findings provide insights into the genetic regulation of E. pyrifoliae pathogenicity, suggesting potential avenues for further research aimed at understanding and controlling this bacterial pathogen by targeting pdeF to mitigate apple black shoot blight disease.

• Journal of Haehwa Medicine
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• v.2 no.2
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• pp.219-246
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• 1993

In 1991, Obesity rate of South Korea has reached to 18.7%. Because of economical development, the pattern of diet is exchanged from carbohydrate to rich protein and fat. The more problem is not only obesity of adult but also one of little child. Obesity is induced to diabetes mellitus, hypertension, artherosclerosis, hyperlipoidemia. heart and C.V.A disease, etc. In Woman, special important ploblem is the complex of beauty about Woman's figure. In Oriental Medicine, the factor of obesity is mainly regarded as dampness. And there are many treatments and methods to body weight loss, but obesity patients dislike to use them because of their side effects and inconvenience, intolerance. Now ear acupuncture is applied on so many disease because of its easy handly, non-side effect and high efficiency in clinics. Here obesity acupuncture is used to ear and whole body acupuncture. Because they react eachother for lack point. Therefore, in order to investigate the effect of obesity acupuncture and develop non-drug, non-starvation etc, we analyzed 453 the cases of body weight loss patients treated with ear and whole body acupuncture in Oriental Medicine Hospital of Jeon-Ju Woo-Sug University from April.1.1992. to March.17. 1993. The results were summarized as follows. 1. Distribution of sex ; male (4.4%), Female(95.6%) 2. Distribution of age in descending order ; 30s, 20s, 40s, 10s, 50s, below 10s, abowe 60s. The 20s-30s are group made up 60.7% of the group. 3. Distribution of occupation in descending order; housewife, student, service, salaried, merchant, teacher, farmer, inoccupation. 4. Distribution of human coporal constitution in descending order : Tae-Eum-In, So-Eum-In, So-Yang-In. 5. Distribution of body height and weight, 155-164cm ; 71.1%, 60-70kg, 74.6% are majority. 6. Distribution of weight variation, 2-6kg(71.0%) is majority, also 13-14kg(0.4%). 7. Distribution of duration in descending order ; 1-3 years, 3-6 years, 1-12months, above 10 years but in success, 1-12 months, 1-3 years, 3-6 years, above 10 years. Therefore, we know that the shorter duration of obesity is, the more loss of body weight. 8. Past experiences to body weight loss; Yes(69.5%), No(30.5%). The success rate accordant with the past temporary experiences shows that the cases without experience is higher than the ones with experience. 9. In distribution of times(treatments), 10 times is top. The rate of body weight loss is the highest in 14 times. Therefore, I think that one would need at least 10 times. in order lose body weight 10. Distribution of body weight variation in treatments times is at 2 times(3-4kg loss), and surprisingly is 14kg loss at above 15 times. 11. Distribution of symptoms improvement, in descending order ; heavy sense in body, dec. of appetite, inc.of exercise, lumbago, edema, knee pain, inc.of urine, inc. of fullness sense, thirsty, disease of gynecology, white tung, chest burning, heart burning, dec.of tobacco, drink taste. motion sickness, allergy, water eczema, arthma, belching. 12. Distribution of snack; Yes(87.4%), No(78.6%) 13. Distribution of exercise; Yes(21.4%), No(78.6%) 14. Distribution of sleeping times, above 7 hours(79.0%) 15. Distribution of the reason to body loss, the complex of beauty(68.7%) is top. 16. Distribution of side effect in obesity acupuncture, constipation (17.4%) is top. 17. Distribution of method in body weight loss ; dietary treatment (31.1%), sauna(26.7%), exercise(19.7%), the center of body weight loss (15.0%) herb-med and starvation treatments (5.1%), hand-finger acupuncture (hand-foot acupuncture) is 1.6%, diet pill(0.3%), etc(0.6%).

• The Korean Journal of Nuclear Medicine
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• v.25 no.2
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• pp.286-293
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• 1991

$^{123}I$, which is applied for the thyroid and other in vivo kinetic study, has a special role in life sciences. The 159 KeV $\gamma-ray$ from $^{123}I$ is almost ideally appropriate for the current imaging instrumentation. Its decay mode (electron capture) and short half-life (13.3 hr) reduced the burden of radiation dose to the patients, and its chemical property makes it easy to synthesize the labelling compounds. In this experiment, the production of $^{123}I$ via the nuclear reaction $^{124}Te(p,2n)^{123}I$ with 28 MeV protons was sutdied. $TeO_2$ is used as a target material, because it has good physical properties. The target was prepared with $TeO_2$ powder and was molten into a ellipsoidal cavity (a=14 mm, b=10 mm, $270.8mg/cm^2$ thick) of pure platinum. The irradiation was carried out in the external proton beam with incident energies range from 28 MeV to 22 MeV, and current was $30{\mu}A$. The loss of $TeO_2$ target was significantly reduced by using $4\pi-cooling$ system in irradiation. The dry distillation method was adopted for the separation of $^{123}I$ from irradiated target, and when it was kept 5 minutes at $780^{\circ}C$, its result was quantitative. The loss of the target material $(TeO_2)$ was below 0.2% for each production run and $^{123}I$ from the dry distillation apparatus was captured with 0.01 N NaOH in $Na^{123}I$ form, then the pH of the solution was adjusted to $7.5\sim9.0$ with HC1/NaOH. The $Na^{123}I$ solution was passed through $0.2{\mu}m$ membrane filter, and sterilized under high pressure and temperature for 30 minutes. The production of $^{123}I$ is acceptable for clinical application based on the quality of USP XXI.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.147-151
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• 2009

Purpose: 2-[$^{18}F$]Fluoro-2-deoxy-D-glucose ([$^{18}F$]FDG) particularly plays as a important role in Positron Emission Tomography (PET) imaging in nuclear medicine. Domestic [$^{18}F$]FDG auto synthesizers are installed in Seoul National University Bundang Hospital (SNUBH) at June 2008, these modules were known that it's synthetic yields were guaranteed in average $45{\pm}5%$ so far. To improve yields and convenience of domestic [$^{18}F$]FDG auto synthesizer, numerous trials in reaction time, base concentration, pressure and temperature were performed to increase [$^{18}F$]FDG yields. Materials and Methods: Several synthetic factors (temperature, time and pressure) and shortcoming were corrected based on many evaporation test. Syringe dispensing of tetra-butylammonium bicarbonate (TBAB) was replaced with micro pipette to prepare tetrabutyl ammonium fluoride salt ([$^{18}F$]TBAF). Troublesome refill of liquid nitrogen every 2 hours which was used to protect vacuum system was changed to charcoal cartridge, base guard filter. To monitor the volume of delivered $[^{18}O]OH_2$ from cyclotron by surveillance camera, we set up the volumetric vial on the cover of the module. In addition to, the recovery vial was added in [$^{18}F$]FDG production system to recover [$^{18}F$]FDG loss due to the leak of valve ($V_{13,14}$) in [$^{18}F$]FDG purification process. Results: When we used micro pipette for adding TBAB ($30\;{\mu}L$ in 12% $H_2O$ in acetonitrile), this quantitative dispensation has enabled to improve $5.5{\pm}1.7%$ residual fluorine-18 activity in fluorine separation cartridge compared to syringe adding. Besides, the synthetic yields of [$^{18}F$]FDG has increased $58{\pm}2.6%$ (n=19), $58{\pm}2.9%$ (n=14), $60%{\pm}2.5%$ (n=17) for 3 months. The life cycle of charcoal cartridge and base vacuum was 3 months prior to filling liquid nitrogen every 2 hours and additional side separator can prevent pump corrosion by organic solvent. After setting of volumetric indicator vial, the operator can easily monitor the total volume of irradiated $[^{18}O]OH_2$ from cyclotron. The recovery vial can be used for the stabilizer when an irregular [$^{18}F$]FDG loss was generated by the leak of valves ($V_{13,14}$). Conclusions: We has optimized appropriate synthetic conditions (temperature, time, pressure) in domestic [$^{18}F$]FDG auto synthesizer. In addition to, the remodeling with several accessories improve yields of domestic [$^{18}F$]FDG auto synthesizer with reliable reproducibility.

• Journal of Periodontal and Implant Science
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• v.44 no.1
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• pp.13-19
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• 2014

Purpose: The purpose of this study was to retrospectively evaluate the survival of periodontally hopeless teeth that were intentionally extracted and replanted after a delay and to compare the radiographic characteristics of the survival group with those of the failure group. Methods: The clinical and radiographic data from patients who underwent delayed intentional replantation between March 2000 and July 2010 were reviewed. Twenty-seven periodontally hopeless teeth were extracted and preserved in medium supplemented with antibiotics for 10-14 days. The teeth were then repositioned in the partially healed extraction socket and followed for 3 to 21 months. The radiographic parameters were analyzed using a paired t test and the cumulative survival rate was analyzed using Kaplan-Meier analysis. Results: Seven replanted teeth failed and the overall cumulative survival rate was 66.4%. In the survival group, the amount of bone loss was reduced from 68.45% to 34.66% three months after replantation. There was radiologic and clinical evidence of ankylosis with 5 teeth. However, no root resorption was found throughout the follow-up period. In the failure group, bone formation occurred from the bottom of the socket. However, a remarkable radiolucent line along the root of a replanted tooth existed. The line lengthened and thickened as time passed. Finally, in each case of failure, the tooth was extracted due to signs of inflammation and increased mobility. Conclusions: Delayed intentional replantation has many advantages compared to immediate intentional replantation and could serve as an alternative treatment for periodontally involved hopeless teeth. However, techniques for maintaining the vitality of periodontal structures on the tooth surface should be developed for improved and predictable results.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.21 no.1
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• pp.37-41
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• 2010

Background and Objectives : Transient minor voice changes after thyroidectomy are not infrequent complaints even in cases without any evidence of recurrent laryngeal nerve damage. However, clinical course, diagnosis and management of such voice changes are not fully understood. This study aimed to evaluate the clinical characteristics of minor voice changes after thyroidectomy. We also tried to assess the significance and feasibility of superior laryngeal nerve monitoring and to find out the optimal evaluation tools for such voice changes after thyroidectomy. Materials and Method : Nine adult patients who received total thyroidectomy without evidence of recurrent laryngeal nerve injury were enrolled for this prospective study. Voice evaluations were performed preoperatively and 3 months postoperatively ; acoustic analyses including voice range profile, aerodynamic study, stroboscopic evaluation and subjective voice assessment with questionnaires. The external branch of superior laryngeal nerve was monitored by nerve stimulator after ligation of superior thyroidal vessels. Results: Four of nine patients complained their voice change at 3 months after the surgery. Three of them reported complete recovery of their voice at 6 months after the surgery. Acoustic analysis revealed significant decrease in their phonatory range especially with high tone loss. Questionnaires related to singing was more sensitive than previously well-known "voice handicap index". Stimulation of the superior laryngeal nerve was feasible in most of the cases (94.4%), but it failed to show any correlation with minor voice changes after thyroidectomy. Conclusion : Minor voice changes were not rare events during the first 6 month after thyroidectomy. Decrease in phonatory range with high tone loss and therefore, discomfort in singing was the most common finding. Superior laryngeal monitoring was feasible but it was not a sensitive tool for the prediction of minor voice change after thyroidectomy.