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Petrology of the Cretaceous volcanic rocks in northern Yucheon Minor Basin, Korea (북부 유천소분지에 분포하는 백악기 화산암류에 대한 암석학적 연구)

  • Sang Wook Kim;Sang Koo Hwang;Yoon Jong Lee;Jae Young Lee;In Seok Koh
    • The Journal of the Petrological Society of Korea
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    • v.7 no.1
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    • pp.27-36
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    • 1998
  • The volcanic piles in the northern Yucheon Minor Basin area are the Hagbong basaltic rocks, the Chaeyaksan basaltic rocks, the Jusasan andesitic rocks, the Unmunsa rhyolitic rocks, and the Tertiary voicanics. Stratigraphically, from the lowermost, (1) the Hagbong basaltic rocks are composed mainly of basaltic tuff with two olivine basalt flows intercalated, (2) the Chaeyagsan basaltic rocks are predominantly in tuffs and agglomerate with 3 basaltic flow interlayers, (3) the Jusasan andesitic rocks consist of thick piles of alternated sequences of 4 andesite flows and 5 andesitic tuffs and tuffaceous sediments and (4) the Unmunsa rhyolitic rocks which embed some rhyolite and obsidian are dominant in tuffs such as ash flow and crystal welded tuff. These volcanics reveal distinguishable characteristics in petrochemistry. In discriminating by major elements, the Hagbong and the Chaeyagsan basaltic rocks are alkaline, whereas the latter is also spilitic. In comparison, the volcanic rocks of the Jusasan andesitic rocks and the Tertiary sequences are characteristically calc-alkaline although their distribution is spatially separated. On the other hand, the variations in immobile trace elements indicate that the Hagbong basaltic rocks range from alkaline to calc-alkaline and from WPB/VAB transition to VAB, whereas the Chaeyagsan basaltic rocks are calc-alkaline WPB/VAB transition type and the two others calc-alkaline VAB. In order to show such a variety in their rock series of the volcanic rocks, the environment during their magma generation, magma rising, and post-eruption alteration could be positively considered.

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Antioxidant activities of soymilk added with green tea and rosemary extract (녹차와 로즈마리 추출물을 첨가한 두유의 항산화 활성)

  • Ryu, Ji-yeon;Song, YeonWoo;Moon, Jeong Yong;Jun, Neung-Jae;Kim Cho, Somi
    • Food Science and Preservation
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    • v.24 no.6
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    • pp.871-878
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    • 2017
  • The objective of this study was to compare antioxidant activities of green tea, rosemary, lemon and bamboo leaves extracts using three different extraction methods (80% ethanol sonication extraction, distilled water autoclave extraction, distilled water extraction at room temperature). As a result, green tea and rosemary extracts showed relatively high antioxidant activities compared with those of lemon and bamboo leaves. These green tea and rosemary extracts were subsequently added to soymilk and their mixtures were examined for antioxidant activities. Soymilk added with 10% green tea distilled water autoclave extracts and distilled water at room temperature extracts showed relatively high DPPH, $85.09{\pm}2.26%$, $84.38{\pm}1.97%$, and ABTS radical scavenging activities, $73.43{\pm}2.78%$, $81.34{\pm}4.78%$, respectively. On the other hand, soymilk added with 10% rosemary distilled water autoclave extracts showed remarkably higher DPPH radical scavenging activity while their ABTS radical scavenging ability was similar to that of non-added soymilk. In conclusion, our results suggest that the addition of green tea distilled water autoclave extracts, distilled water at room temperature extracts and rosemary distilled water autoclave extracts to soymilk could contribute to the development of added value soymilk products with increased antioxidant activities.

EVALUATION OF SODIUM DICHLOROISOCYANURATE AS A ROOT CANAL IRRIGATION SOLUTION;Cl- CONCENTRATION, pH, CYTOTOXICITY AND ANTIMICROBIAL EFFECT IN VITRO (이염화이소시아뉼산나트륨 제재의 근관세척액 사용 가능성 평가;염소이온농도, 세포독성, 항균성 및 pH)

  • Lee, Woo-Cheol;Kang, Bong-Sun;Kim, Cheol-Ho;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
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    • v.28 no.5
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    • pp.425-430
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    • 2003
  • The purpose of this study was to evaluate the clinical applications of the Sodium Dichloroisocyanurate effervescent tablet as a routine root canal irrigant by performing several in vitro tests such as $Cl^{-}$ content. cytotoxicity. antimicrobial effect as well as its pH level compared to the equivalent concentration of sodium hypochlorite solution. 1. Sodium Dichloroisocyanurate demonstrated lower level of $Cl^{-}$ concentration than each dilution of sodium hypochlorite solution. Both solution has increased level of $Cl^{-}$ as the concentration of each solution increased. There was no significant change of $Cl^{-}$ concentration in sodium hypochlorite as time goes by. However. $Cl^{-}$ concentration in Sodium Dichloroisocyanurate was increased. 2. The antimicrobial effects of both solutions were increased when their concentrations were increased. One day after dilution. antimicrobial effect of Sodium Dichloroisocyanurate was slightly higher than sodium hypochlorite. however. there was no difference in 1 week dilution solution. One month dilution solution of sodium hypochlorite still retain its activity. but antimicrobial effect of Sodium Dichloroisocyanurate was drastically decreased 1 month after dilution. 3. The cytotoxicity of Sodium Dichloroisocyanurate was rather higher than same concentration of sodium hypochlorite solution until 1 week after dilution. Then in 1 month. cytotoxicity of Sodium Dichloroisocyanurate was decreased than that of 1 week dilution solution. especially 4% Sodium Dichloroisocyanurate solution has almost no toxicity. However. 1% and 2% sodium hypochlorite solution has unchanged moderate degree of cytotoxicity after the dilution. Furthermore. 4% sodium hypochlorite solution showed high level of toxicity. 4. The pH level of Sodium Dichloroisocyanurate showed that the solution was weak acid (pH5). On the other hand. sodium hypochlorite was revealed as a strong alkaline solution (pH12). There was no change in pH following the dilution of each solution. As results. Sodium Dichloroisocyanurate solution fully satisfy the basic requirements as a root canal irrigation solution. However. we strongly recommend to use this solution clinically in low concentration and try to apply into the root canal within 1 week after dilution.

Biochemical Changes in Brassica Seedlings Due to Cold Treatment (Brassica속 작물 유묘에서 저온처리에 따른 생화학적 변화)

  • Park, Woo-Churl;Park, Kyeong-Bae;Nam, Min-Hee
    • Applied Biological Chemistry
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    • v.38 no.3
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    • pp.207-211
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    • 1995
  • In order to determine the mechanism of cold tolerance in crops, changes in biochemical factors related with the biological reduction of molecular oxygen upon cold shock treatment were analyzed at an early stage of Brassica germination. As the cold shocked seedlings were recovered under the normal growth condition for 24 hours, the peroxidase activities in cold sensitive rape(B. napus) and cold tolerant 'Sandongchae'(B. campestris) were considerably increased by 33% and 87% in root fraction and, 84% and 206% in hypocotyl, respectively. The content of superoxide($H_2O_2$) in hypocotyl fraction was dramatically accumulated until 8 hours after recovery and then gradually decreased. The extent of superoxide accumulation was severer in B. napus than B. campestris. At 24 hours after cold shock, $H_2O_2$ content was decreased to the nearly control level in B. campestris but still remained by 38%, in E. napus. Even though $H_2O_2$ content in hypocotyl fraction was decreased only 2% in B. napus during cold shock, while in B. campestris it was severely decreased about 15%. On the other hand, the cold shock at 3 days after Uniconazole treatment was more effective in increase of peroxidase activity than each separate treatment.

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Antioxidant activities and quality characteristics of noodles containing Allium senescens L. (두메부추 첨가 국수의 항산화 활성 및 품질특성)

  • Yang, Eun-Young;Han, Young-Sil
    • Korean Journal of Food Science and Technology
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    • v.52 no.2
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    • pp.156-161
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    • 2020
  • This study was designed to evaluate the quality characteristics and antioxidant activities of noodles containing Allium senescens L. powder (0, 2, 4, 6, and 8%). With an increase in the consumption of Allium senescens L., there was a decrease in pH (p<0.001), water absorption ratio, volume expansion ratio, and turbidity (p<0.05). The colorvalue showed that the addition of Allium senescens L. decreased the L and b values. On the other hand, a value was increased (p<0.001). The mechanical texture of the noodles containing Allium senescens L. was decreased by the addition of Allium senescens L. considering its hardness and chewiness; however, it increased the adhesiveness, springiness, and cohesiveness (p<0.001). In the sensory evaluation, the noodles with 4% Allium senescens L. powder showed the best results (p<0.001). The total polyphenol content, total flavonoid content, DPPH radical scavenging, and reducing power were increased upon addition of Allium senescens L. powder (p<0.001).

Isolation, identification, and probiotic characteristics of Bacillus strains affecting the biogenic amine content in fermented soybean paste (발효 된장의 바이오제닉 아민 함량에 영향을 미치는 바실러스균의 분리 동정 및 프로바이오틱 특성)

  • Lim, Eun-Seo
    • Korean Journal of Microbiology
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    • v.55 no.2
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    • pp.131-142
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    • 2019
  • The primary objective of this study was to determine the content of biogenic amines in Korean traditional fermented soybean pastes (doenjang) and to isolate potential probiotic Bacillus sp. with the ability to inhibit biogenic amines accumulation. There were significant differences in the bacterial cell counts, pH value, titratable acidity, salinity, and biogenic amine content between the samples. Among Bacillus strains isolated from doenjang, Bacillus (B.) licheniformis DB102, B. subtilis DB203, B. stearothermophilus DB206, Bacillus sp. DB209, Bacillus sp. DB310, B. coagulans DB311, B. cereus DB313, B. amyloliquefaciens DB714, Bacillus sp. DB917, B. cereus DB 915, B. subtilis DB1020, and Bacillus sp. DB1022 were found to be able to produce biogenic amines. On the other hand, biogenic amine-degrading strains were identified as Bacillus sp. DB403, Bacillus sp. DB407, B. subtilis DB517, B. licheniformis DB612, and B. subtilis DB821. In particular, Bacillus sp. DB407 and B. subtilis DB821 showed probiotic properties including tolerance to artificial digestive juices, adherence to intestinal epithelial cells, resistance to antibiotics, and antibacterial activity against biogenic amine-producing strains. In conclusion, the two probiotic Bacillus strains may be considered as the suitable starter for manufacture of fermented soybean foods with low biogenic amines content.

Analysis of Progression Levels for Meta-modeling Knowledge of Science Gifted Students through Modeling (모델링을 통한 과학영재 학생들의 메타모델링 지식 발달 단계 분석)

  • Kim, Sung Ki;Kim, Jung Eun;Park, Se-Hee;Paik, Seoung-Hye
    • Journal of The Korean Association For Science Education
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    • v.39 no.3
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    • pp.457-464
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    • 2019
  • This study aims to explore meta-modeling knowledge of gifted students through the modeling. To do this, five gifted students were asked to do modeling related to candle burning, and all the processes of modeling were observed and then individual interviews were conducted. As a result of the study, two students were classified as first level and three students were classified as second level. The students of the first level did not have any model generation or model-based prediction activities, and observation was the most meaningful activity. On the other hand, the students of the second level performed all four modeling processes. However, the generation of the model and the prediction using the model were relatively strong. The data they gained from the experiments was perceived as just confirming the absolute model. No student was found in Level 3 or Level 4. The results of this study show that gifted students remain at the progression level of recognizing the model as an objective reality, and in order to cultivate a true scientist, it is necessary to educate the gifted students to recognize the subjectivity of the model.

Effects of Goal Management Training According to Bilateral Activities of Autism Spectrum Disorders: Pilot Study (자폐스펙트럼 장애 아동에게 목표관리 훈련이 양측활동에 미치는 영향: 예비연구)

  • Ahn, Si-Nae
    • Journal of Korean Society of Neurocognitive Rehabilitation
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    • v.10 no.2
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    • pp.1-7
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    • 2018
  • The study has compared normally developed children and children who were diagnosed as autism spectrum in goal management training them to observe the effect. The research was conducted to four normally developed children and four children who were diagnosed as autism spectrum, and all subjects were provided with identical goal management training. The children and the caregivers have selected desired objectives activity, and all three activities were followed by goal management training. Intervention periods were conducted ten times in total, two times a week for five weeks, and eight subjects in the two groups were trained one on one by the researcher. The training time was 40 minutes for every session. The descriptive statistics and frequency analysis were used as the statistical method, and the Mann-Whitney test, the nonparametric statistical analysis, was conducted to compare the difference between the two groups. Goal management training for two groups did not show a statistically significant difference in terms of the performance status of Canadian Occupational Performance Measure (p>.05). In the summary of Bruininks-Oseretsky Test of Motor Proficiency (2nd) which evaluates the motor skill, there was a statistically significant difference between the autism spectrum disorder group and normal group (p<.05). Additionally, the two groups showed a statistically significant difference in eye-hand coordination sub-test among Developmental Test of Visual Perception (2nd) which evaluates the visual perception performance (p<.05). The research has confirmed the applicability of goal management training to children with autism spectrum compared to the normally developed children, and it has confirmed the effectiveness of the training.

Removal of COD and Color from Anaerobic Digestion Effluent of Livestock Wastewater by Advanced Oxidation Using Microbubbled Ozone (마이크로버블 오존 고도산화를 이용한 축산폐수 혐기소화 배출수의 COD와 색도의 제거)

  • Lee, Inkyu;Lee, Eunyoung;Lee, Hyejung;Lee, Kisay
    • Applied Chemistry for Engineering
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    • v.22 no.6
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    • pp.617-622
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    • 2011
  • Ozone-based advanced oxidation was applied for the treatment of anaerobic digestion effluent of livestock wastewater. Initial COD and color value were 930 mg/L and 0.04, respectively, and the 1/10-diluted wastewater was used for the study. The treatment characteristics were compared between the conventionally generated ozone ($105{\mu}m$) and microbubbled ozone ($13{\mu}m$). The use of microbubbled ozone improved the removal of chemical oxygen demand (COD) and color by 85% and 26%, respectively, compared with the conventionally bubbled ozone. The application of microbubbled $O_3/UV$, $O_3/H_2O_2$, $O_3/UV/H_2O_2$ combinations resulted in 5~10% higher color removal than ozone alone, which implies that the contribution of UV or $H_2O_2$ is not significant in color removal. On the other hand, COD removal could be increased two folds compared with ozone alone through $O_3/UV/H_2O_2$ combination. The contribution of $H_2O_2$ was bigger than UV for COD removal with microbubbled ozone. Due to the enhancement of dissolved ozone and radical activity, the microbubbling enabled us to additional COD removal even after stopping ozone supply in the presence of UV or $H_2O_2$.

NCS proposal for industrial security (산업보안 분야에 대한 NCS 제안)

  • Park, Jong-Chan;Ahn, Jung-Hyun;Choi, Young-Pyul;Lee, Seung-Hoon;Baik, Nam-Kyun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2022.05a
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    • pp.358-360
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    • 2022
  • Modern society is developing rapidly and technologies that provide convenience in living are developing day by day. On the other hand, the development of cyber attacks that threaten cybersecurity is developing faster, and it still adversely affects the industrial environment, and industrial damage is steadily occurring every year. Industrial security is an activity that safely protects major assets or technologies of companies and organizations from these attacks. Therefore, it is a situation that requires professional manpower for security. Currently, the manpower situation for security is staffed, but knowledge of the understanding and concept of industrial security jobs is insufficient. In other words, there is a lack of professional manpower for industrial security. It is the NCS that came out to solve this problem. NCS is the state standardized ability (knowledge, attitude, skills, etc.) necessary to perform duties in the industrial field. NCS can systematically design the curriculum using NCS as well as help in hiring personnel, and NCS can be applied to the national qualification system. However, in the field of industrial security, NCS has not yet been developed and is still having difficulties in hiring personnel and curriculum. Although the NCS system in the field of industrial security has not been developed, this paper proposes the industrial security NCS to solve the problem of hiring professionals later and to help the field of industrial security NCS to be established later.

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