• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.68-69
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• 2020

Recently, the problem of air pollution is drawing attention as a social problem worldwide. Particularly, fine dust is the biggest issue among air pollutants, and it is analyzed that fine dust is generated from air pollutants such as burning fossil fuels such as petroleum or coal, or exhaust gases from automobiles. In addition, yellow dust originating from China adjacent to Korea flows into the Korean Peninsula in a western wind, causing the concentration of fine dust to deteriorate. Fine dust is a harmful substance to the human body such as asthma or respiratory disease, and awareness of the risk is also increasing to a degree designated as a primary carcinogen. In this study, as a method for improving the indoor air quality, the Properties of the matrix according to the mixing ratio of powdered activated carbon based on blast furnace slag are reviewed. The flexural strength and compressive strength were measured, and a fine dust concentration measurement experiment will be conducted later.

• Microbiology and Biotechnology Letters
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• v.51 no.2
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• pp.184-190
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• 2023

Bioethanol has recently attracted much attention as a sustainable and environmentally friendly alternative energy source. This study aimed to develop a potential process for bioethanol production by fed-batch fermentation using instant dry yeast. To obtain the highest cell growth, we studied the influence of the initial sugar concentrations and pH of sugarcane molasses in batch fermentation. The batch system employed three levels of sugar concentrations, viz. 10%, 15%, 20% (w/v), and two levels of pH, 5.0 and 5.5. The highest cell growth was achieved at 20% (w/v) and pH 5.5 of molasses. The fed-batch system was then performed using the best batch fermentation conditions, with a molasses concentration of 13% (w/v) which resulted in high ethanol concentration and fermentation efficiency of 15.96% and 89%, respectively.

• Journal of Oriental Neuropsychiatry
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• v.35 no.1
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• pp.27-36
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• 2024

Objectives: This study aimed to assess the effects of a 1-night, 2-day mental health healing center program on the physical stress, autonomic nervous system health, brain activity levels, brain stress, concentration levels, and Patient Health Questionnaire-9 (PHQ-9) scores of dementia patients and their caregivers. Methods: Forty-eight dementia patients (average age 80 years, 14 males and 34 females) and 48 caregivers (average age 65.23 years, 14 males and 34 females) participated in the program. Pre- and post-assessments were conducted to measure the variables. Results: Dementia patients experienced reduced physical stress, increased brain activity levels, decreased brain stress, improved concentration levels, and a significant decrease in PHQ-9 scores (p<0.05). However, there was a tendency for a decline in autonomic nervous system health among dementia patients. A significant decrease in physical stress was seen in caregivers, but no other significant differences were observed. Conclusions: While the 1-night, 2-day mental health healing center program did not produce significant changes in the caregivers of dementia patients, it exhibited overall positive effects in dementia patients. Consequently, mental healing programs should be utilized effectively for dementia patients. Furthermore, investigating the significance of ongoing programs for the mental well-being of dementia caregivers is imperative, mirroring the attention given to dementia patient care.

• Science of Emotion and Sensibility
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• v.24 no.1
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• pp.37-44
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• 2021

A study was conducted on the effects of improving concentration by obscuring the peripheral vision using a blindfold that only covers the left and right sides of the field of view. The blindfold was trapezoidal in shape (5 × 4.8 cm in length and width) and was fixed to the left and right sides of the glasses with fixing clips. The material was a black-colored polypropylene (PP) and weighed 2.3 g including the clip. Qualitative and quantitative evaluations were performed on 50 healthy college students during the 15 days of using a blindfold. The qualitative analysis was performed utilizing a questionnaire regarding the improvement of concentration and the structure of the blindfold. EEG was measured while watching a learning video that required attention for quantitative analysis, and signal power and ERD/S analyses were performed for the mid β band (15-20 Hz) at the F4 position, which was the frontal lobe. The results showed that 40 of the 50 people reported improved concentration when they wore a vision shield, and 80% of the total subjects found it to be effective. From the quantitative evaluation, the ERS peak (p = 0.023) and the ERD + ERS peak value showed a significant difference (p = 0.017). In conclusion, concentration still improved even if only the left and right visual fields were used. Thus, it is expected that blindfolding could be used in various environments that require concentration.

• The Korean Journal of Nuclear Medicine Technology
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• v.27 no.1
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• pp.29-35
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• 2023

Purpose The concentration of PSA (Prostate Specific Antigen) after radical prostatectomy in prostate cancer patients is a predictor of biochemical recurrence, and the AUA (American Urological Association) is defined as biochemical recurrence when the concentration of PSA is measured at 0.2 ng/mL or more, and when the concentration is measured at 0.2 ng/mL or more at the retest. This standard is also applied our hospital. In this laboratory, the PSA reagent using IRMA (Immunoradiometric Assay) is used, and the sensitivity at a very low value was not as good as the reagent used in the department of laboratory medicine. This study aims to increase the reliability of the results by improving the precision and sensitivity of very low values. Materials and Methods As a reagent for the study, PSA reagent using IRMA was used. As a method to improve the precision and sensitivity of very low values, a variation method on the serum volume(25 uL, 50 uL, 100 uL, 200 uL) was studied, and variation usefulness evaluation was conducted. The evaluation items were compared the results of precision, analytical sensitivity, recovery rate, dilution test, high-dose hook effect test, parallel test and very low concentration values(n = 20). Results The validation results were displayed in the order of 25 uL, 50 uL, 100 uL, 200 uL. As the serum volume increased, it was confirmed that CV (Coefficient of Variation)(%) improved. Analytical sensitivity(ng/mL) was 0.038, 0.041, 0.017, 0.015 and recovery rate(%) was 101±3, 101±3, 99±2, 97±4. very low concentration values(ng/mL) between each volume(n=20) were 0.135±0.068, 0.076±0.050, 0.048±0.034, 0.046±0.034. and high dose hook effect appeared as the serum volume increased. Conclusion Through the variation usefulness evaluation, it was confirmed that as the serum volume increased, the precision and sensitivity improved at very low concentration values. However, it is necessary to pay special attention to the occurrence of high-dose hook effect as the serum volume increases. In the case of tests that requires very low concentration values, it is thought that the reliability of the result will be increased if the variation method is properly used after the variation usefulness evaluation.

• Journal of the Korean Society of Earth Science Education
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• v.13 no.3
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• pp.211-225
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• 2020

The purpose of this study was to investigate and analyze pre-service teachers' eye-movement in science textbooks in the learning process, whether they perceived "arrow" presented in textbooks, and changes in eye-movement by arrows. For the study, an eye-tracker, a eye-movement tracking device, was used, and 10 pre-service teachers attending a teacher training college were selected and conducted. The science textbook unit used in the research was the "Weather and Our Life" unit, one of the areas of earth science. As a result of the study, first, it was investigated that pre-service teachers devote more time to texts rather than illustrations in the learning process of science textbooks. Second, it was analyzed that pre-service teachers did not pay attention to the "arrow" presented in science textbooks. Third, it was confirmed that in order for "affordance of the eye-movement by arrow" to occur, sufficient concentration on "arrow" should be made. These findings suggest the importance of the learner's visual attention to learning elements in science textbooks such as "arrow". In addition, it suggests the importance of developing a textbook editing design that can induce visual attention to learning elements in textbooks through eye-movement research data for effective learning.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.5
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• pp.224-228
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• 2014

Recently, the demands for separation/recovery of valuable metals such as nickel or tin from copper based alloys has been attracting much attention from the viewpoints of environmental protection and resource utilization. In this report, experimental results on concentration increasement of nickel and tin compared to the previous report are investigated. Ni is successfully separated by a organic solvent and reduced to the metal powder whose concentration is over 98 %. Sn is separated by a selective solution method and its concentration is increased to 97.5 % by three consecutive solution and reduction process. Crystal structure, surface morphology and microstructure of the separated samples are studied.

• The Korean Journal of Ecology
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• v.27 no.1
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• pp.15-20
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• 2004

With attention to different human activities around Anzali wetland and introduction of different pollutants containing heavy metals into this water ecosystem and absorption and accumulation of heavy metals in shell and muscle of Astacus leptodactylus which is native benthose of Anzali wetland and enjoys food and economic importance; Sampling of waters and sediments from 18 stations and shell and muscle of Astacus leptodactylus from 5 stations had been conducted. After biometric evaluation of Astacus leptodactylus, the chemical analysis of the samples by using international and standard methods and then their heavy metals content was determined by Atomic Absorpotion Spectrophotometer (AAS), model P.U 9400 philips. Result of the analysis stated that; 1) The mean values of Cr, Zn, Pb, Ni, V in Anzali waters were 6.4, 184.5, 28.8, 28.9, 47.1 ($\mu$ gr/lit) respectively, which comparing to the international standards, is not suitable for drinking, but it can be used for agricultural and aquacultural purposes. Even though the concentration of heavy metals in sediments were high, there are in range of acceptable limit for aquatics organisms; 2) Comparatively, the concentration of heavy metals in shell and muscle of Astacus leptodactylus in Anzali wetland (Cr, Zn, Pb, Ni, V in shell were 3.48, 109.3, 14.13, 7.17, 36.2 and in muscle were 2.98, 131.98, 3.12, 4.77, 9.05 ppm respectively) were more than what is determined for Aras dam (in shell were 1.6, 224.3, 7.8, 7.6, 10.3 and in muscle were 1.4, 60.2, 0.45, 2.7, 4.4 mg/kgr respectively); 3) For all samples, concentration of heavy metals in all Astacus leptodactylus in Anzali wetland and Aras dam, was at tolerance level for human consumption; 4) There was no association with significant difference between weight and size of Astacus leptodactylus with absorption and accumulation of heavy metals; but there was a significant association between heavy metals content in water and in sediments, and in sediments, shell and muscle of Astacus leptodactylus in Anzali wetland.

• The Korean Journal of Nuclear Medicine
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• v.18 no.1
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• pp.39-44
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• 1984

It is well known that glucagon, like insulin, is very important in the moment-to-moment control of the homeostasis of glucose, and of amino acids. Glucagon has been shown to have potent glycogenolytic, gluconeogenic and lipolytic activities. Attention to its role in the pathogenesis of diabetes mellitus and hypoglycemia has been also advanced recently. To evaluate the diurnal variation of plasma glucagon concentration, we measured serum glucose, insulin, and plasma glucagon every 30 minutes or every hour in 7 normal Korean adults. Results were as follows: 1) Although plasma glucagon concentration showed wide individual variations, it had a tendency to decrease after meals. After lunch and dinner, plasma glucagon concentration had gradually declined and reached its nadir at postprandial 2-2.5 hours. The minimal level of plasma glucagon was at 4 A.M. 2) Serum insulin:plasma glucagon ratios were increased promptly after meals. Especially after lunch, its peak was prominent $(3.65{\pm}1.95)$. The minimal level of serum insulin:plasma glucagon ratio appeared at 6 A.M.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.2
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• pp.25-56
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• 2000

Trace element are involved in enzymatic activities, immunological reactions. physiological mechanisms. Deficiency in some trace elements, such as iron and iodine. is still an important health problem, The role of trace elements deficiency is suspected in various clinical situations and is now confirmed by well designed supplementation studies. However, the importance of trace elements as chinese herbal constituents is not sufficiently appreciated by the oriental medical profession, although in recent years a significant increase of new finding on their essential character in chinese herbal medicine occurred. It is well known that herbal medicine contains a variety of trace elements which would show therapeutic effects with active components in herbal medicine . In china, recent work showed some positive correlation between trace element and traditional chinese medicine (TCM) in terms of therapeutic effects even if their role in therapeutic effects is still obscure. In korea, not much attention has been on the therapeutic importance of trace element contained in herbal medicine Here, the therapeutic effects of trace element in TCM were reviewed and summarized. 1. Iron, copper, zinc and manganese are mainly contained in TCM. In addtion, chromium, magnesium, molybdenum, nickel, alminium, cobalt, arsenic and selenium has been studied for their therapeutic effects 2. Zinc, is decreased in patients who have deficiency of kindney(腎虛) and chronic disease. Fe is decreased in patients who have deficiency of blood(血虛). However copper is increased in patients who have chronic disease and hepatic disease.3 Iron concentration is high in herbs used for tonifying and nourishing yin or blood(補陰補血藥) Zinc concentration is high also in herb used for tonifying kidiney and vital essence(補腎補精藥). In addition. copper concentration Is high in herb used for replenishing qi(補氣藥) 4 In herbal drugs, the therapeutic substances in TCM are not only organic but also inorganic. It seems that trace elements would be one of components in herb for its therapeutic effects. This indicates that therapeutic effects of TCM should be extended not only to herb itself, bur also to trace elements contained in herb.