• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2002년도 추계학술대회
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• pp.135-139
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• 2002

Yeast cells respond to condition of amino acid starvation by synthesizing GCN4, a typical eukaryotic transcriptional activator, which regulates the expression of many amino acids biosynthetic genes. By introducing point mutations in the DNA binding domain of GCN4, mutants with normal DNA binding activity but defective in transcriptional activity were isolated to identify unknown proteins that could suppress the mutant phenotype under an amino acid depletion condition. As a result, SSB(Stress-Seventy B) subfamily proteins were identified as suppressors of mutant GCN4. SSB proteins were known as a member of yeast hsp70 family that probably aids passage of nascent chain through ribosomes. Among them, the mechanism of suppression by SSB2 on the defective GCN4 mutant strains is under investigation. Gcn4p directly interacts with Ssb2p through the basic DNA binding domain of GCN4. It suggests the possibility that physical interaction might induce the transcriptional activation of Gcn4p.

• 자원리싸이클링
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• 제15권2호
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• pp.50-57
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• 2006

해양에서 발생하는 목질 폐기물의 재활용 방안의 일환으로 폐 어류 상자를 원료로 활성탄을 제조하는 방안을 검토하였다. 폐 황산을 활성화제로 하여 온도에 따른 활성탄의 흡착능의 변화를 검토한 결과 실험조건에서 $650^{\circ}C$부근에서 최대의 흡착능이 관찰되었으며 이보다 온도가 상승할 경우 열적 분해로 인해 흡착능이 감소하는 것으로 나타났다. 활성시간은 약 120분 정도가 적절한 것으로 파악되었으며 $550^{\circ}C$ 및 60분의 활성화 조건에서 원료 물질과 활성화제의 무게비가 1:3의 조건일 때 최대 흡착능이 관찰되었다. 활성화 조건은 황산의 농도가 1.2M일 때 최적인 것으로 조사되었으며 활성화제의 종류에 따른 활성능을 비교한 결과 황산은 질산에 비해 활성탄의 흡착능면에 있어서는 그 효과가 더욱 큰 것으로 파악되었으나 수율에 미치는 영향은 두 경우 뚜렷한 차이가 없는 것으로 나타났다. 제조된 활성탄은 중성 영역에서 분산도가 높은 것으로 관찰되었으며 전 pH 영역에 걸쳐 음의 전하를 띠는 것으로 파악되어 금속 이온 함유 폐수에 효과적인 흡착제로 사용될 수 있을 것으로 사료되었다.

• Toxicological Research
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• 제21권1호
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• pp.57-62
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• 2005

To investigate the mutant induction of wild ginseng culture extract, we performed chromosomal aberration assay with chinese hamster lung cell in vitro. The test concentration of the extract was decided for the standard with the 50% suppression of cell propagation in the cell. The concentrations for the chromosome test were 1,250, 2,500 and 5,000 ㎍/ml with metabolic activation (+S, 6 hours treatment), 1,100, 2,200 and 4,400 ㎍/ml without metabolic activation (-S, 6 hours treatment) 800, 1,600 and 3,200 ㎍/ml without metabolic activation (-S, 24 hours treatment). No significant increase in chromosome aberrations was observed at any of these concentrations both in the absence and presence of metabolic activation system. Cyclophosphamide monohydrate (CPA) and ethylmethanesulfonate (EMS) caused a significant increase in chromosome aberration. These results may be concluded that wild ginseng culture extract is not capable of inducing chromosome aberration in cultured chinese hamster lung cell regardless of metabolic activation and genotoxicity of that is negative under the present experimental condition.

• 한국환경과학회지
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• 제10권5호
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• pp.373-380
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• 2001

In recent years, the demand of activated carbon has been increasing steadily because of the environmental problems. Among them waste and water treatment and removal of poisonous gas were invorved. Therefore, in this study, activated carbon was made from the waste chinese cabbage and measured the iodine adsorption ability, carbonization yield, and activation yield of the produced activated carbon. The result showed that the carbonization yield was decreased when carbonization temperature was increaed and that the optimal carbonization temperature was $600{\circ}C$. The optimal concentration of NaOH for removing ash in the raw sample was 1~2N. The range of iodine adsorption number of activated carbon using chinese cabbage at $600{\circ}C$. carbonization was 610.82mg/g to 1019.58mg/g. The activation result of carbonization sample showed that the optimal activation condition was the carbonization at $400\circ}C$ and the activation at$700{\circ}C$. So the production of activated carbon using chinese cabbage was possible in the aspect of reuse of resource and decrease of environmental pollution compared to the commercial activated carbon.

• 한국가축번식학회지
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• 제18권2호
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• pp.121-126
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• 1994

This study was conducted to examine the condition of activation of the nuclear transplant bovine embryos. In vitro fertilized(IVF) and nuclear transplant embryos(NTs) were co-cultured with bovine oviduct epithelial tissue(BOET). NTs were treated with cycloheximide(CHXM) for 0 to 6 h after electrofusion to investigate the activation conditin of recipient ooplast. Then, the infljence of the CHXM treatment timing on the cleavage and development of NTs were investigated in relation to the nuclear transplant time. The cleavage rates of NTs were increased with the increasing time of the CHXM treatment from 0 to 6 h (54.7 to 91.3%, P<0.01). Similar trend was shown in the development into the morula or blastocyst stage, but very limitted. Activation of enucleated oocytes prior to fusion enhanced development of NTs compared with that post fustion. This result suggests that the frequency of activation of NTs can be greatly enhanced by treating with CHXM for 6 h. The result also suggests that if blastomeres of unknown cell cycle stage are used, activation of enucleated oocytes prior to fusion enhances development of NTs.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권3호
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• pp.209-214
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• 1999

This paper deals with the effects of activation process of MgO thin film on the dielectric characteristics of surface discharge type AC PDP. The discharge voltage decreased with increase in the MgO activation time and temperature until $400^{\circ}C$ under the condition of clean high vacuum. However, for the sample activated above $430^{\circ}C$ the discharge voltage increased. These results may be explained by the MgO morphology change and surface cleaning in the process of activation.

• 한국산학기술학회논문지
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• 제12권2호
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• pp.888-894
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• 2011

블랙보드 구조는 복잡하고 풀이 방법이 잘 규정되어 있지 않은 문제들을 다루기 위한 구조이다. 블랙보드구조를 사용하는 시스템의 효율을 높이기 위하여, 본 논문은 블랙보드의 상태가 변화할 때마다 문제 풀이에 잠재적으로 기여할 수 있는 활성 지식 원천들(knowledge source activations)의 집합을 신속하게 탐지하기 위한 메커니즘을 제안한다. 제안된 메커니즘은 블랙보드 데이터와 지식 원천들의 활성화 조건들(activation conditions) 간의 패턴 매칭을 신속하게 수행하기 위하여 지식 원천들이 등록하는 활성화 조건들로부터 Rete 네트워크를 생성하여 사용한다.

• 한국안전학회지
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• 제18권3호
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• pp.81-87
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• 2003

Latex polymers are widely used for adhesive, binder, paint etc. Especially the PVAc(Polyvinyl acetate) latex which manufactured by vinyl acetate and vinyl alcohol as protective colloid is a useful environmentally friendly adhesive. To increase useful property of PVAc latex, this study was carried out for checking thermal characteristics and physical condition of PVAc latex by DSC, FT-IR, Pyrolyzer GC-MS. The activation energies of thermal decomposition for 40, 48, 56, 64% solid content of PVAc latex were found as 28.1-36.0kcal/mol by Kissinger's method and 17.2-22.0kcal/mol by DSC method. Actually, reasonable solid content could be consiered as 56% because of activation energy and adhesive characteristics. According to the effect of protective colloid for 4, 10, 15, 20wt%, the activation energy shows same tendency to both method and in case of l5wt% has been found as the highest activation energy. The mechanism of thermal decomposition was mainly estimated by main chain scission, not by side group on FT-IR analysis. Main component of Pyrolzer GC-MS result were consisted of $CH_3COOH$, $CH_3$, $H_2O$ and light gases(CO, $CO_2$, $CH_4$ etc).

• 한국운동역학회지
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• 제26권4호
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• pp.421-426
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• 2016

Objective: The purpose of this study was to investigate how different levels of compression exerted on the femoral region (known as the power zone) by coated fabric influences the activation and anaerobic capacity of the rectus femoris. Method: Three different levels of compression on the rectus femoris of the participants, namely 0% (normal condition), 9% (downsize), and 18% (downsize), were tested. The material of the fabric used in this study was nonfunctional polyurethane. Surface electromyography test was used to investigate the activation of the rectus femoris, while the isokinetic test (Cybex, $60^{\circ}/sec$) and Wingate test were used to investigate the maximum anaerobic power. Results: The different compression levels (0%, 9%, and 18%) did not improve the strength and anaerobic capacity of the knee extensor. However, knee flexor interfered with activation of the biceps femoris, which is an agonist for flexion, during 18% compression. Conclusion: Compression garments might improve the stretch shortening cycle effect at the time of eccentric contraction and during transition from eccentric to concentric contraction. Therefore, future studies are required to further investigate these findings.

• 영어어문교육
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• 제3호
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• pp.95-122
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• 1997

The purpose of this research was to investigate the effects of content and formal schema on reading comprehension. Five hundred fiftynine subjects from high school were assigned to one of the following levels and treatment conditions : (1) Higher level & Schema Activation, (2) Higher level & Non-schema Activation, (3) Lower level & Schema Activation, and (4) Lower level & Non-schema Activation. To evaluate the effects of schema activation. two experiments were conducted : one was related to the content schema and the other to the formal schema. To evaluate the effects of content schema, three different types of tests were conducted : (1) cloze test, (2) guessing the meanings of nonsense words, and (3) immediate recall test. To evaluate the effects of formal schema instruction, four kinds of tests were conducted : (1) sorting the sentences according to the importance, (2) identifying the signal words, (3) immediate recall test, and (4) identifying the specific information. For content schema condition, results indicated that the subjects given the titles or pictures before reading in "Content Schema Activation" treatment had better grades than those of the other treatment in all types of tests. regardless of their levels. Schema activation helped the subjects to increase the cognitive predictability of missing words and to participate in the tasks more actively with risk-taking. And it was also shown that good readers tend to process the words meaningfully, while poor readers tend to process the words phonetically or morphologically. Formal schema activation through teaching the text organization also had a significant influence on three types of tests: sorting the sentences according to the importance, identifying the signal words, and immediate recall test, but not on identifying the specific information. The implications from this study can be briefly noted as follows : (l) In teaching reading, the student's background knowledge should be activated as a pre-reading activity. (2) In reading, it is more important to emphasize the student's schema than the features of the text. (3) Various educational interventions should be introduced, especially for the lower level students. (4) Teaching text structures can be a powerful method for the top-down processing strategy.