• Title/Summary/Keyword: Y$_2$O$_3$

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An Interpretive Inquiry into the Guidance Experiences of Senior Elementary Teachers (초등학교 원로교사의 생활지도 경험에 관한 해석학적 탐구)

  • Lee, Jeong-Hee
    • The Korean Journal of Elementary Counseling
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    • v.7 no.1
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    • pp.111-133
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    • 2008
  • The purpose of this study was closely to explore the guidance experiences of senior elementary teachers who have had over 30 years of teaching experiences in elementary school based on interpretive(or hermeneutic) inquiry. The entry research question was 'What are the guidance experiences of senior elementary teachers like?' Seven senior elementary teachers working for O elementary School in G city participated in this study voluntarily. Each participant was interviewed twice in a consecutive manner. 14 periods of interview were completed all together and each period took about 40-60 minutes. In conclusion, this study conceptualized the guidance experiences of the senior elementary teachers(participants) as follows: First, the concepts of guidance held by the participants were conceptualized as 1) supporting and caring activity helping students to lead joyful school life, 2) assisting activity helping students to grow on good basic life habits, 3) character building activity helping students to lead integrative growth. Second, the fields and contents of guidance held by the participants were conceptualized as basic life habits, manners, and health & safety. Interestingly, these concepts were evolved in connection with their personal, practical teaching experiences rather than in-service teacher education. Third, the guidance methods frequently used by the participants were co-work with parents, exemplary storytelling, counselling, and praise. The participants applied these methods differently according to the grade, individual difference, and school curriculum policy to some degree. Fourth, the participants have experienced a lot of struggles with students, teachers, and parents in doing their guidance practices throughout the whole teaching career. Their guidance experiences commonly shifted from more teacher-centered or authoritative to more student-centered or relational way as their teaching years accumulated. Interestingly, all the participants more or less lived as lifelong learners to create their own right space as senior teachers in today's competitive and challenging landscape. This study strongly suggests that responsible teacher education can playa great role of enabling senior teachers to cope with guidance issues successfully. Compared with the speedy social change, the teacher education in Korea had been so authoritative, provider-based, subject-based until recently and it have not met the needs and wants of the elementary teachers in field. This trend has significantly hindered them from catching up with the needs of the speedy social change in terms of contemporary guidance issues. This study is limited in that the data is solely collected based on interview. So, an observational research is strongly suggested in order to uncover the situated understanding of the guidance experiences of elementary senior teachers.

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A Calculation Method of in vivo Energy Consumption in Estimation of Harvesting Date for High Potato Solids (고 고형분함량 감자의 수확시기 예측모형을 위한 식물체내 에너지 소모량 추정)

  • Jung, Jae-Youn;Suh, Sang-Gon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.55 no.4
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    • pp.284-291
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    • 2010
  • A simulation modeling for predicting the harvesting date with high potato solids consists of development of mathematical models. The mathematical model on potato growth and its development should be obtained by using agricultural elements which analyze relations of solar radiation quantity, temperature, photon quantity, carbon dioxide exchange rate, water stress and loss, relative humidity, light intensity, and wind etc. But more reliable way to predict harvesting date against climatic change employs in vivo energy consumption for growth and induction shape in a slight environmental adaptation. Therefore, to calculate in vivo energy loss, we take a concept of estimate of the amount of basal metabolism in each tuber on the basis of $Wm={\int}^m_tf(x)dt$ and $Tp=\frac{Tm{\cdot}Wm^{Tp}}{Wm^{Tm}}$. In the validation experiments, results of measuring solid accumulation of potato harvested at simulated date agreed fairly well with the actual measured values in each regional field during the growth period of 2005-2009. The calculation method could be used to predict an appropriate harvesting date for a production of high potato solids according to weather conditions.

The Role of Universities and the Characteristics of Knowledge Networks in Three Regions (지역 대학의 역할과 지식 네트워크 특징에 대한 연구 : 3개 지역 비교를 중심으로)

  • Jeong, Dae-hyun;Kwon, O-Young;Jung, Yong-Nam
    • Journal of Korea Technology Innovation Society
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    • v.20 no.2
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    • pp.487-517
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    • 2017
  • In the context of an increased demand in universities' expansion of networks between other innovation actors, this research attempts to make a comparison on university-centered SCIE knowledge networks between regions. Using regional comparison, we have looked into these networks in regards to their characteristics, the importance of regional boundaries, and the effect of the regional industrial policy. As a result of this comparative analysis, we discovered that the point universities and research universities hold high centrality in regional knowledge networks, and that the characteristics of regions are reflected into this network. For instance, the Gyeonggi province had a preeminent level of industry-academy relationship, while for Daejeon it was public research institutions and academy, and Gangwon province it was between academy between academy. As a network analysis based on journals above SCIE levels, regional boundaries were not very clear in the network structures. However, within these boundaries, the impact of regional industrial policies were proven to be stronger in the Gang-won province where the academy-academy network was most prominent. The implication of this research outcome is that for regional innovation, government should more actively implement policies that can link academic institutes' knowledge to industry by expanding knowledge networks. In addition, we emphasize on the necessity of a regionally-appropriate policy, rather than a generalized industrial policy. And fundamentally, in regards to innovation, establishing a sound industrial infrastructure for regional development and efforts to link relevant actors are required.

A Monte Carlo Study of Dose Enhancement according to the Enhancement Agents (몬테칼로 기법을 이용한 방사선 선량증가 물질에 따른 선량증가 효과 평가)

  • Kim, Jung-Hoon;Kim, Chang-Soo;Hwang, Chulhwan
    • Journal of radiological science and technology
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    • v.40 no.1
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    • pp.93-99
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    • 2017
  • Dose enhancement effects at megavoltage (MV) X and ${\gamma}-ray$ energies, and the effects of different energy levels on incident energy, dose enhancement agents, and concentrations were analyzed using Monte Carlo simulations. Gold, gadolinium, Iodine, and iron oxide ($Fe_2O_3$) were compared as dose enhancement agents. For incident energy, 4, 6, 10 and 15 MV X-ray spectra produced by a linear accelerator and a Co-60 ${\gamma}-ray$ were used. The dose enhancement factor (DEF) was calculated using an ICRU Slab phantom for concentrations of 7, 18, and 30 mg/g. The DEF was higher at higher concentrations of dose enhancement agents and at lower incident energies. The calculated DEF ranged from 1.035 to 1.079, and dose enhancement effects were highest for iron oxide, followed by iodine, gadolinium, and gold. Thus, this study contributes to improving the therapeutic ratio by delivering larger doses of radiation to tumor volume, and provides data to support further in vivo and in vitro studies.

Mutagenicities of Carbonyl Compounds Derived from Maillard Reaction and their Desmutagenicity Mechanisms (Maillard 반응 유래(由來) 저분자 카르보닐화합물의 돌연변이원성과 그 억제기구)

  • Kim, Seon-Bong;Yeom, Dong-Min;Do, Jeong-Ryong;Yoon, Hyeung-Sik;Byun, Han-Seok;Kim, In-Soo;Park, Yeung-Ho
    • Korean Journal of Food Science and Technology
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    • v.21 no.3
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    • pp.435-440
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    • 1989
  • The present study was attempted to investigate the mutagenicities of carbonyl compounds(methyl glyoxal, glyoxal, diacetyl, dihydroxyacetone, glycolaldehyde, glyceraldehyde and furfural) derived from Maillard reaction toward Salmonella typhimurium TA 100(base-substitution mutant) without metabolic activation . And for further Investigation of mutagenicity mechanism including desmutagenicity, active oxygen scavengers (cysteine, ${\alpha}-tocopherol$, tris (hydroxymethyl) aminomethane, catalase, ascorbic acid) and reducing agents (glutathione, sodium bisulfite) were also used. Among carbonyl compounds tested, methyl glyoxal, glyoxal, dihydroxyacetone, glycolaldehyde and glyceraldehyde exhibited mutagenicities, and methyl glyoxal showed the strongest mutagenic activity. On the other hand , the mutagenicities of carbonyl compounds were significantly suppressed by cysteine, tris (hydroxymethyl) aminomethane, glutathione and sodium bisulfite. Also, these active oxygen scavengers and reducing agents alone did not show mutagenicity in the present study.

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Anti-inflammatory and apoptosis improving effects of sulfasalazine and Cinnamomi cortex and Bupleuri radix mixture in TNBS-induced colitis mouse model (TNBS로 유발된 마우스 대장염모델에서 설파살라진, 육계와 시호 복합 추출물의 항염증 및 세포 자멸 개선효과)

  • Kim, Kyeong Jo;Shin, Mi-Rae;Kim, Soo Hyun;Kim, Su Ji;Lee, Ah Reum;Kwon, O Jun;Kil, Ki-Jung;Roh, Seong-Soo
    • Journal of Applied Biological Chemistry
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    • v.60 no.3
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    • pp.227-234
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    • 2017
  • Inflammatory bowel disease (IBD) is including Crohn's disease and ulcerative colitis. Sulfasalazine commonly used in IBD, possibly has various side effects after high dosage and long term intake. The present study aimed to investigate the sulfasalazine and combination with herbal medicine on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced in mice model. TNBS-induced mice were injected through a flexible catheter 4 cm in length 1.6 mg TNBS. Animals were divided into five groups (n=12): Normal group, TNBS control group, Sulfasalazine (30 mg/kg) group, Sulfasalazine (60 mg/kg) group, Sulfasalazine (30 mg/kg)+Cinnamomi cortex and Bupleuri radix mixture (30 mg/kg) (SCB) group. Administration groups were fed extract during 7 days. The inflammatory, and apoptotic protein levels were determined using western blotting. SCB treatment showed an outstanding effectiveness in counteracting the IBD, as assessed by reduction of body weight loss, down-regulation of pro-inflammatory proteins and cytokines, and by inhibition of proteins related to apoptosis. This is the first report that sulfasalazine and Cinnamomi cortex plus Bupleuri radix mixture improve the severity of experimental IBD through the inhibition of both inflammation and apoptosis. We confirm that the SCB treatment instead of sulfasalazine alone may be promising as an alternative therapeutic plan against IBD, without any evidence of adverse effects.

Labeling Efficiency of $^{99m}Tc$-Labeled RBC Due to Labeling Time Change (표지시간 변화에 의한 $^{99m}Tc$과 적혈구 표지효율)

  • Dong, Kyeong-Rae;Kim, Ho-Seong;Choi, Seong-Kwan
    • Journal of radiological science and technology
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    • v.30 no.3
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    • pp.259-263
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    • 2007
  • For the preparation of $^{99m}Tc$-labeled RBC, $10{\sim}20\;{\mu}g/kg$ of Stannous(II) chloride and $10{\sim}40\;min$ of preparation was used. For finding out the effect of contrast agent, the blood samples were collected in three days, seven days, and 1 months after the diagnostic procedure. In the normal volunteer, the concentration of reducing agent and preparation time did not effect on the radiochemical yield. But in the patients, 10 mg of Stannous(II) chloride and 60 min incubation times was shown high radiochemical yield. Contrast agent has a significant effect on the radiochemical yield. Although the blood samples which were collected after seven days of diagnostic procedure did not effect on the radiochemical yield of $^{99m}Tc$-labeled RBC, but the radiochemical yield of $^{99m}Tc$-labeled RBC which was prepared with a sample of high concentration of contrast agent in blood led to low radiochemical yield. For these samples, the modified method showed high radiochemical yield than previous in vivo preparation method. The recommended method is followed. Blood collecting was performed at 30 minutes after injection of reducing agent, and it is centrifuged for removal of plasma. After addition of $^{99m}TcO^-_4$, sample reservoir was rotated. After addition of normal saline, and it is centrifuged for separation of saline. Then $^{99m}Tc$-labeled RBC was obtained after removal of saline.

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Antioxidant and α-Glucosidase Inhibitory Activities of the Extracts of Aster koraiensis Leaves (국내산 벌개미취 잎 추출물의 α-glucosidase 억제능 및 항산화 활성 평가)

  • Lee, Tae Gu;Hyun, Soo Wang;Lee, Ik Soo;Park, Bong Kyun;Kim, Jin Sook;Kim, Chan Sik
    • Korean Journal of Medicinal Crop Science
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    • v.26 no.5
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    • pp.382-390
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    • 2018
  • Background: The plant Aster koraiensis has long been used as an ingredient in folk medicine. It has been reported that Aster koraiensis extract (AKE) prevents the progression of diabetes-induced retinopathy and nephropathy. However, although these beneficial effects of AKE on diabetes complications have been identified, the antidiabetic effects of AKE have not yet been completely investigated and quantified. In the present study, the glucose-lowering and antioxidant effects of aqueous and ethanolic AKEs were evaluated. Methods and Results: The glucose-lowering effects of aqueous and ethanolic (30%-, 50%-, and 80%-ethanol) AKEs were investigated via ${\alpha}$-glucosidase inhibitory assays. The mode of inhibition by AKEs on ${\alpha}$-glucosidase was identified through kinetic analysis. The total antioxidant capacity of each of the 4 AKEs was evaluated by assessing their conversion rate of $Cu^{2+}$ to $Cu^+$. The content of chlorogenic acid and 3,5-di-O-caffeoylquinic acid, the bioactive compounds in AKE, in each extract were analyzed by high performance liquid chromatography (HPLC). The AKEs showed potent ${\alpha}$-glucosidase inhibitory activity with mixed inhibition mode, and significant antioxidant capacity. Conclusions: These results of this study suggested that the AKEs tested had ${\alpha}$-glucosidase inhibitory and antioxidant effects. Among the extracts, the 80% ethanol extract showed the most significant ${\alpha}$-glucosidase inhibitory activity, with a half maximal inhibitory concentration ($IC_{50}$ value) of $1.65{\pm}0.36mg/m{\ell}$ and a half maximal effective concentration ($EC_{50}$ value) for its antioxidant activity of $0.42{\pm}0.10mg/m{\ell}$. It can therefore be used as a source of therapeutic agents to treat diabetes patients.

Studies on Biological Activities of the Polysaccharides and Oligosaccharides of Orostachys japonicus (와송 다당체 및 올리고당류의 생리 활성)

  • Kim Ki Hoon;Kim Eun Young;Kim Yea Oon;Baek Geum Ok;Kim Han Bok;Lee Dong Seok
    • Korean Journal of Microbiology
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    • v.40 no.4
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    • pp.334-341
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    • 2004
  • Polysaccharides were prepared from Orostachys japonicus by extration with hot steam water (OJPl). The OIPl fraction was further purified by Sephadex G-50 gel filtration chromatography to produce FI (polysaccharides) and FII (oligosaccharides) fraction. The average molecular masses o fFI and FII fraction were determined to be 3050 kDa and 13 kDa, respectively. The antimicrobial activity of OIPl was tested against 8 strains of bacteria and one strain of yeast by the disc diffusion method, fluorescein diacetate (FDA) method and broth dilution method. The OIPl exhibited a very strong growth inhibition to Candida albicans. The OIPl remarkably sup­pressed the growth of Salmonella typhimurium and Staphylococcus aureus. The OIPl showed higher growth inhibition to Escherichia coli and Pseudomonas aeruginosa than propolis, positive control. When the anticancer activity of the OIPl, FI or FII was examined against human cancer cell lines and the Sarcoma 180 cells, these widely suppressed the proliferation of cell lines in the MTT assay and morphology study. Especially, they remarkably inhibited the growth of A549, HeLa and AGS cells. Also treatment of cancer cells with OJPl, FI or FII induced apoptotic cell death characterized by DNA fragmentation. The OJPl, FI or FII exhibiting various biological activities such as antimicrobial activity and anticancer activity is expected to be developed as new biohealth products.

Expression and Antibacterial Activity of Recombinant Human Lactoferrin in Methylotrophic Yeast, Pichia pastoris (Methylotrophic Yeast, Pichia pastoris에서 사람 락토페린의 발현 및 항균성 연구)

  • Lee Sang O;Im Eun Mi;Nam Eun Joo;Lee Hyune Hwan
    • Korean Journal of Microbiology
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    • v.40 no.4
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    • pp.348-354
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    • 2004
  • The expression and antibacterial. activity of recombinant human lactoferrin (hLf) was studied from meth­ylotrophic yeast Pichia pastoris. The gene encoding hLf, isolated from human breast cDNA library, was subcloned into the expression vector, pPIC3.5K under the control of AOX1 promoter. The gene was integrated into the host chromosome and was identified by Southern blotting. The expression of the integrated gene was investigated by RT-PCR, Northern blotting, SDS-PAGE and Western blotting. Discrete band corresponding to hLf was detected from the SDS-PAGE, which was confirmed by Western blotting. The expression was also confirmed by RT-PCR and Northern blotting. The antibacterial activity of the recombinant hLf (rhLf) was investigated using Staphy­lococcus aureus ATCC 6538P and Micrococcus flavus ATCC 10240 as test organisms. The rhLf showed strong antibacterial activities against the bacteria. Furthermore, many Gram-negative animal pathogens such as E.coli ATCC8739, 25922, and Salmonella typhimurium 114 and 115, Pseudomonas fluorescens ID 963 I, P. aeruginosa KCCM 11802, and Gram-positive bacteria Bacillus mesentericus were also inhibited in their growth by the rhLf.