• Journal of the Mineralogical Society of Korea
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• v.21 no.3
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• pp.271-281
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• 2008

The "Noerog", a traditional green mineral pigment occurs as veins or cavity-filings in the basaltic pyroclastic rocks of Quaternary Epoch in Mt. Noeseong in Janggi-myeon, Pohang. The "Noerog stone" mainly consists of celadonite with minor chlorite/smectite, mordenite and opal. Celadonite grains are several hundreds to several tens of ${\mu}m$ in size. The particle sizes under several tens of fm are likely to coagulate to aggregates. The coloring rate increases rapidly with decreasing particle size under $71{\mu}m$. The hiding power is maximum in the particle sizes of $0.2\sim0.3{\mu}m$. The resistance properties of the Noerog to both the light and the bacteria are absolutely superior to ordinary chemical pigments. The transparency of the Noerog is maximum in the nano-powders under 200 nm. Examination of the color of the Noerog pigment which has been prepared by traditional technique for "dancheong" shows that the best coloring effect is found in the particle sizes under $32{\mu}m$ and that the painting was not successful for the Noerog of particle size over $32{\mu}m$.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.90-96
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• 2017

Gray mold disease, cause by Botrytis cinerea, occurs severe damage on varieties of fruit and vegetable production, and have no a critical control method. In case of chemicals control, it is a trigger emergence of drug resistance strains due to using them continuously. In addition, the pathogen is difficult to control naturally because it is possible to survive regardless of host status. In this study, microorganisms were isolated from tomato flower and hive samples and in order to select suitable microbial control agents for tomato gray mold disease. During six-months study, we isolated 1,004 isolates from flower and 925 isolates from pollinator hive samples. Among them, 6 strains were selected based on result of antifungal activity test. The selected strains showed not only strong antifungal activity against gray mold pathogen, but also cellulase and protease enzyme activities. The selected strains were identified as Paenibacillus polymyxa. In plant assay, P. polymyxa prevented the gray mold disease occurrence near 75%.

• Journal of Oral Medicine and Pain
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• v.35 no.1
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• pp.19-29
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• 2010

Phytoncide, essential oil of trees, has microbicidal, insecticidal, acaricidal, and deodorizing effect. The present study was performed to examine the effect of phytoncide on Candida albicans, which is a commensal colonizer of the mucous membranes but has become an opportunistic pathogen. C. albicans was incubated with or without phytoncide extracted from Hinoki (Chamaecyparis obtusa Sieb. et Zucc.; Japanese cypress) and then changes were observed in its optical density, cell viability and morphology. As concentrations of phytoncide added to the culture medium increased, optical density and cell viability of C. albicans decreased. Minimum inhibitory concentration of phytoncide for C. albicans was observed to be 0.25%, and minimum fungicidal concentration was 0.5%. Numbers of morphologically atypical cells with electron-dense cytoplasm and granules and increased with increasing concentration of the phytoncide. At higher concentrations of phytoncide, compartments and organelles in the cytoplasm became indistinguishable. The overall results indicate that the phytoncide used for this study has a strong antimicrobial activity against C. albicans. Therefore, the phytoncide may be used as a candidate for prevention and therapeutic agent against oral candidiasis.

• Journal of fish pathology
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• v.5 no.2
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• pp.135-142
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• 1992

The absorption and excretion times of oxolinic acid(OX) used in farms as new aquatic antibiotics commonly were evaluated with determination of the effects of water temperature and feeding to parameters by using the bioassay technique. On the same time, antibacterial activity and the complex formation of oxolinic acid with serum proteins of two different fishes were compared to those oxytetracycline(OTC). With more than 10 times lower MIC values than those of OTC in the strains among 13 analyzed fish pathogens. OX did not show the decresed antibacterial activity by the binding of serum proteins in carp and tilapia. It implies more powerful potential of OX as aquatic medicine OTC. The serum concentration of OX after different administrations the oral, i.m., i.v and dipping methods were compared. The higher beginning concentration in serum and faster excretion times were obserbed in i.m. and dipping methods respectively. In the oral and i.m. administration, peak serum concentration after 24－48 hrs and slow excretion times demonstrated in both methods. These pharmacokinetic characteristics similar at $30^{\circ}C$ and $20^{\circ}C$ water temperature conditions, however, beginning serum concentration of OX in fish dipped in $50mg/\ell$ sol after starvation for 2 wks was appeared lower than those of fed fish. It suggests the importance of biological condition of the gill or skin for absorption of antibiotics after dipping administration.

• Journal of the Korea Convergence Society
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• v.11 no.7
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• pp.377-387
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• 2020

This study is a retrospective and descriptive research to identify the factors affecting development of spontaneous abortion in women of childbearing age. The subjects totaled 198 females aged 20~45 who had experienced childbirth or spontaneous abortion at least once, and data was collected for one month since July 2019 through self-reporting questionnaires. The results showed that the factors affecting development of spontaneous abortion were use of panty liners (daily: reference, 1~2 times a week: B=-1.74, no: B=-0.77) and antimicrobials (often or a lot: reference, small or normal: B=-0.71, no: B=0.79), occupational groups (inoccupation: reference, service industry employee: B=0.73, white collar: B=1.22, professional: B=0.63, manager: B=1.54), and exposure-risk behavior toward endocrine-disrupting chemicals (B=0.81) during pregnancy, and their explanatory power for development of spontaneous abortion was 24.4% (R²=.24). As a result, it is necessary to prevent endocrine-disrupting chemicals exposure and pay attention to the occupational environment during pregnancy in order to reduce the development of spontaneous abortion.

• Journal of Life Science
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• v.19 no.3
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• pp.390-396
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• 2009

In this study, extracts from S. officinalis were tested for antioxidative effects and inhibitory activities against $\alpha$-amylase, angiotensin converting enzyme (ACE) and xanthine oxidase (XOase). The content of total phenolic compounds in water, 60% ethanol, 60% methanol and 60% acetone extracts were 36.2, 42.7, 40.3 and 39.6 mg/g, respectively. In 60% ethanol extracts, the EDA by DPPH free radical scavenging test of S. officinalis was $66.3{\pm}2.2%$ at $200{\mu}g/ml$. The inhibition rate of ABTS was $97.6{\pm}0.1%$, the antioxidant protection factor was $2.26{\pm}0.63$ PF, and TBARS was $0.62{\pm}0.05$ (${\times}100{\mu}M$ in the control and $0.29{\pm}0.02$ (${\times}100{\mu}M$). Also in 60% ethanol extracts of S. officinalis, the inhibitory activity against XOase was 78% and was not shown to be against ACE. According to the $12.6{\pm}0.14\;mm$ of clear zone formed, the inhibition rate against $\alpha$-Amylase was 7.6% at $200{\mu}g/ml$ of phenolics content. Antimicrobial activities of 60% ethanol extracts of S. officinalis against Helicobacter pylori exhibited an inhibition rate of $12.5{\sim}66.1%$ according to the $10{\sim}15\;mm$ of clear zone at $50{\sim}200{\mu}g/ml$. The results suggest that the 60% ethanol extracts from Salvia officinalis L. will be useful as natural antioxidants and functional food sources.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.1-7
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• 2004

The effects of chitosan dipping treatments with different molecular weights on the meat quality of Hanwoo(Korean Cattle) beef during refrigerated storage were investigated. The beef(M. Semimembranosus) were dipped in 0.5% chitosan(in 1% acetic acid) with two different molecular weights(Mw=150 and 600 kDa) for 5 min and stored at $1^{\circ}C$(90% RH). The pH was significantly(p<0.05) higher in chitosan(600 kDa) group than in the other groups. The L＊ value for 3 days was significantly(p<0.05) higher in chitosan (600 kDa) group, but it was not significantly(p>0.05) different after 6 days. The a＊ value of day 0(before storage) was not significantly(p>0.05) different among the treatment groups, however the a＊ value of day 12 was significantly(p<0.05) higher in chitosan(150 kDa) group. The metmyoglobin(%) was significantly(p<0.05) lower in chitosan(600 kDa) group. The total bacterial counts of day 0(before storage) were significantly(p<0.05) lower in chitosan(600 kDa) group, but during storage, the chitosan(150 kDa) group was effective in antibacterial activity. The chitosan(l50 kDa) group had significantly(p<0.05) lower shear force than the other groups over time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.269-282
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• 2020

This paper presents the scientific basis for the significance and physiological activity of gongyang as tributes, focusing on the four summer fruits, i.e., grapes, watermelons, oriental melons, and dragon fruits, which were used as one of the yukbeopgongyang in Yeongsanjae's thorough literature review (yeongsanjae and 2010.3~2020.2 published fruit research). As a result of the study, the fruit is not obtained from fruit trees, but from enlightenment. Chemically, the fruit had a high content of antioxidants, such as polyphenol and flavonoid. The fruit had excellent DPPH and ABTS+ radical scavenging activities and reducing power. The skin of the fruits, the non-edible part, had higher physiological activity than the flesh, the edible part. Therefore, further studies on the physiological activity in each part of dragon fruit and regarding how to ingest and utilize the peel of the four fruits need to be conducted.

• Journal of Elementary Mathematics Education in Korea
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• v.11 no.1
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• pp.43-59
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• 2007

The goal of this thesis was to examine the effects of applying meta-problems to elementary school mathematics class In their achievements, beliefs and attitudes. To achieve this goal the following research questions were asked. a. What effects does the class applied with meta-problem have on students' mathematical achievements? b. What effects does the class applied with meta-problem have on students' mathematical beliefs and attitudes? To answer questions, an experimental study was designed and conducted. The subjects were 6th-grade students at S Elementary School located in Dobong-Gu, Seoul where the researcher teaches. Among them, the class that the researcher teach was chosen as the experimental group. During the experimental study, a teaching-learning with meta-problems was applied to the experimental group and a teaching-learning with general problems was applied to the comparative group. To examine changes in the mathematical achievements of the experimental group and the comparative group, a post-test of mathematical achievements was conducted and the results were t-tested. As well, to find answers to the second research question, a pre-test and a post-test of mathematical beliefs and attitudes were conducted on the experimental group and the results were t-tested. The results of this study were as follows First, the experimental group which was taught applying meta-problems got higher mathematical achievement than the comparative group. Second, the class with meta-problems did not bring significant changes in students' mathematical beliefs and attitudes. Synthesizing the study results above, a teaching-learning with meta-problems is a teaching-learning method that can accommodate problem solving naturally in school mathematics and give a positive effect on students' mathematical achievements.

• Journal of Elementary Mathematics Education in Korea
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• v.15 no.1
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• pp.95-120
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• 2011

Modern society is the age of the information. As new information is springing up every day and pace of change becomes faster, the importance of communication skills is growing. The recent mathematics education is recognized as not a fragmentary mathematical knowledge or results of the learning, but a procedure of mathematical thinking, and the effective expression skill of their mathematical ideas and the ability to forward it to others are regarded very serious. As the method of mathematics evaluation, mathematical essay is introduced to replace the existing multiple-choice written test. This method assess the ability which students have, that express the reorganized knowledge and information according to given situation by themselves. Ultimately, it is expected to help that students get the higher order thinking skills such as logical thinking and creativity. However, definition of elementary mathematical essay is unclear, and proper teaching methods is lacking for each stage of elementary school students. Thus, in this paper, I have defined the concept of elementary mathematical essay and made a foundation of elementary mathematical essay research, then researched about the effective utilization of elementary mathematical essay using school education. Also elementary mathematical essay teaching-learning materials is developed and applied to analyzed the students' responses. Using this program, in real elementary school education, the implications has deduced.