• Progress in Medical Physics
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• v.34 no.3
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• pp.33-39
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• 2023

Purpose: FLASH radiotherapy (RT) using ultra-high dose rate (>40 Gy/s) radiation is being studied worldwide. However, experimental studies such as preclinical studies using small animals are difficult to perform due to the limited availability of irradiation devices and methods for generating a FLASH beam. In this paper, we report the initial dosimetry results of a prototype electron linear accelerator (LINAC)-based irradiation system to perform ultra-high dose rate (UHDR) preclinical experiments. Methods: The present study used the prototype electron LINAC developed by the Research Center of Dongnam Institute of Radiological and Medical Sciences (DIRAMS) in Korea. We investigated the beam current dependence of the depth dose to determine the optimal beam current for preclinical experiments. The dose rate in the UHDR region was measured by film dosimetry. Results: Depth dose measurements showed that the optimal beam current for preclinical experiments was approximately 33 mA, corresponding to a mean energy of 4.4 MeV. Additionally, the average dose rates of 80.4 Gy/s and 162.0 Gy/s at a source-to-phantom surface distance of 30 cm were obtained at pulse repetition frequencies of 100 Hz and 200 Hz, respectively. The dose per pulse and instantaneous dose rate were estimated to be approximately 0.80 Gy and 3.8×10⁵ Gy/s, respectively. Conclusions: Film dosimetry verified the appropriate dose rates to perform FLASH RT preclinical studies using the developed electron-beam irradiator. However, further research on the development of innovative beam monitoring systems and stabilization of the accelerator beam is required.

• Journal of Nutrition and Health
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• v.46 no.3
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• pp.218-225
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• 2013

Although the functional ingredient has been evaluated by the Korea Food and Drug Administration (KFDA) based on scientific evidence, the levels of scientific evidence and consistency of the results might vary according to emerging data. Therefore, periodic re-evaluation may be needed for some functional ingredients. In this study, we re-evaluated scientific evidence for the antioxidant activity of coenzyme Q10 as a functional ingredient in health functional food. Literature searches were conducted using the Medline and Cochrane, KISS, and IBIDS databases for the years 1955-2010 with the search term of coenzyme Q10 in combination with antioxidant. The search was limited to human studies published in Korean, English, and Japanese. Using the KFDA's evidence based evaluation system for scientific evaluation of health claims, 33 human studies were identified and reviewed in order to evaluate the strength of the evidence supporting a relation between coenzyme Q10 and antioxidant activity. Among 33 studies, significant effects for antioxidant activities were reported in 22 studies and their daily intake amount was 60 to 300 mg. Based on this systematic review, we concluded that there was possible evidence to support a relation between coenzyme Q10 intake and antioxidant activities. However, because inconsistent results have recently been reported, future studies should be monitored.

• Journal of Preventive Medicine and Public Health
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• v.55 no.5
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• pp.464-474
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• 2022

Objectives: We introduced the cohort studies included in the Korean Cohort Consortium (KCC), focusing on large-scale cohort studies established in Korea with a prolonged follow-up period. Moreover, we also provided projections of the follow-up and estimates of the sample size that would be necessary for big-data analyses based on pooling established cohort studies, including population-based genomic studies. Methods: We mainly focused on the characteristics of individual cohort studies from the KCC. We developed "PROFAN", a Shiny application for projecting the follow-up period to achieve a certain number of cases when pooling established cohort studies. As examples, we projected the follow-up periods for 5000 cases of gastric cancer, 2500 cases of prostate and breast cancer, and 500 cases of non-Hodgkin lymphoma. The sample sizes for sequencing-based analyses based on a 1:1 case-control study were also calculated. Results: The KCC consisted of 8 individual cohort studies, of which 3 were community-based and 5 were health screening-based cohorts. The population-based cohort studies were mainly organized by Korean government agencies and research institutes. The projected follow-up period was at least 10 years to achieve 5000 cases based on a cohort of 0.5 million participants. The mean of the minimum to maximum sample sizes for performing sequencing analyses was 5917-72 102. Conclusions: We propose an approach to establish a large-scale consortium based on the standardization and harmonization of existing cohort studies to obtain adequate statistical power with a sufficient sample size to analyze high-risk groups or rare cancer subtypes.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.377-382
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• 2014

Micro-/macroporous carbons (MMCs) were prepared using a hollow mesoporous silica capsule (HMSC) as a sacrificial hard template. The carbonization process after the infiltration of furfuryl alcohol into the template-free HMSC material afforded MMC materials in high yield. The hard template HMSC could be removed by HF etching without deteriorating the structure of MMC. The MMC materials were fully characterized by SEM, TEM, PXRD, XPS, and Raman spectroscopy. The replication processes were so successful that MMCs exhibited a hollow capsular structure with multimodal microporosity. Detailed textural properties of MMC materials were investigated by volumetric $N_2$ adsorption-desorption analysis at 77 K. To explore the gas sorption abilities of MMCs for other gases, $H_2$ and $CO_2$ sorption analyses were also performed at various temperatures. The multimodal MMC materials were found to be good sorbents for both $H_2$ and $CO_2$ at low pressure.

• Research in Community and Public Health Nursing
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• v.26 no.1
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• pp.18-30
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• 2015

Purpose: The purpose of this study was to investigate the research methods, types and effects of community health center exercise programs for the elderly. Methods: We established the PICOTS-SD (Participants, Interventions, Comparisons, Outcomes, Timing of outcome measurement, Setting, Study Design), reviewed 583 studies from electronic database of DBpia, KoreaMed, KISS, RISS, NDSL and Pubmed, and finally selected 20 studies based on the inclusion and exclusion criteria. Methodological quality was assessed with the Risk-of-Bias Assessment tool for non-randomized studies. Results: With regard to research methods, the majority of studies on community health center exercise programs for the elderly were performed after 2010 and using non-equivalent control group pretest-posttest research design. As for the types and effects of exercise programs, the exercise period ranged from 6 to 28 weeks, and the most common exercise frequency was three times a week for 60 minutes. In addition, mixed-type and group exercise programs were performed most commonly. Conclusion: The results of this study provide a basis for the development of exercise programs to improve elders' health.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.30 no.3
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• pp.88-99
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• 2019

Objectives: With increasing concerns for the rapidly growing minority population in South Korea, this literature review addressed a range of mental health risks among multiethnic youths (MY) in South Korea by 1) comparing mental health outcomes with those of native-born youths and 2) identifying multiple layers of relevant environmental factors, from family and school relationships to culture. Methods: We reviewed 54 studies that fulfilled specific inclusion criteria. Results: Multiple common risk/protective factors, including family separation, family relationship quality, parental socioeconomic and mental health status, social relationships at school, and cultural acceptance, were noted. Conclusion: In general, empirical evidence indicates that minority youths have relatively heightened risks for emotional and behavioral problems. Future studies must elucidate the complex interplay between multiple risk and protective factors and the long-term adaptation and mental health service utilization of MY.

• Journal of the Korean Magnetic Resonance Society
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• v.18 no.2
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• pp.58-62
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• 2014

Human transmembrane proteins (hTMPs) are closely related to transport, channel formation, signaling, cell to cell interaction, so they are the crucial target of modern medicinal drugs. In order to study the structure and function of these hTMPs, it is important to prepare reasonable amounts of proteins. However, their preparation is seriously difficult and time-consuming due to insufficient yields and low solubility of hTMPs. We tried to produce large amounts of Syndecan-4 transmembrane domain (Syd4-TM) that is related to the healing wounds and tumor for a long time. In this study, we performed the structure determination of Syd4-TM combining the Polarity Index at Slanted Angle (PISA) wheel pattern analysis based on $^{15}N-^1H$ 2D SAMPI-4 solid-state NMR of expressed Syd4-TM and Molecular Dynamics (MD) simulation using Discovery Studio 3.1.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.6
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• pp.703-709
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• 2013

Among many microalgae cultivation types, heterotrophic culture with low cost carbon sources and energy saving culture method is crucial. A result of estimating the effects of pH on wastewater treatment using heterotrophic growing microalgae Chlorella sorokiniana shows that there was no difference in microalgae growth amount and nitrogen, phosphorus removal rate by wide range of pH(5 ~ 9). From pH 5 to 9, total nitrogen, phosphorous and glucose removal rates were 10.5 mg-N/L/d, 2 mg-P/L/d, 800 ~ 1000 mg/L respectively. This study reveals that C. sorokiniana cannot metabolite glycerol heterotrophically, however, glucose and acetate were proper carbon sources for growth and T-N, T-P and TOC removal. This research highlights the potential of heterotrophic microalgal growth with wastewater treatment plant with wide range of pH and carbon sources.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.3
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• pp.319-323
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• 2015

This study investigated the effects of the light conditions on the productivity of scenedesmus dimorphus in the continuous mass cultivation system. To compare the algal productivity according to the light conditions, S. dimorphus was cultivated continuously under the wide range of light intensity(200-600 PPFD) and various light wavelength(white light and red-blue mixed light). After 100 days of cultivation under the different light intensity, the productivity of S. dimorphus increased as light intensity decreased. So, the productivity was maximized as 100 mg/L/d when light intensity was 200 PPFD. In case of light wavelength, the productivity of S. dimorphus was enhanced about 20% with the white light compared to that of the red-blue mixed light. Consequently, the optimal light conditions for the continuous mass cultivation of S. dimorphus were 200 PPFD as light intensity and white light as light wavelength.

• The Journal of Korean Medicine
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• v.31 no.2
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• pp.64-70
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• 2010

Objective: This study aimed to construct an overview of health-related quality of life (HRQOL) scales for application in studies of traditional Korean medicine (TKM). Methods: We analyzed all HRQOL scales from the PROQOLID web site (www.proqolid.org) regarding to classification, application purposes, and translation to Korean version. We also searched clinical studies focused on "Quality of Life" using TKM. Results: A total of 660 HRQOL instruments were analyzed; 99 were for general condition while 559 were disease-specific. Twenty clinical studies for TKM were conduced using HRQOL scales. Conclusion: The adaptation of the international HRQOL instrument is strongly recommended in TKM-associated clinical study, and development of a TKM-specific HRQOL scale is needed for globalization of TKM.