• 에너지공학
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• 제13권4호
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• pp.259-266
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• 2004

세라믹핵연료의 비열기구는 격자 진동 비열, 팽창 비열, 전도전자 및 결함비열 그리고 과잉비열로 구성된다. 비열을 표현하는 모델은 정압비열 항과 팽창비열 항 그리고 결함비열 항으로 구성된다. 본 연구에서는 세라믹 핵연료의 실험자료 또는 발표된 자료들을 종합 분석하였으며, 가장 적합한 모델을 추천하였다. $UO_2$, (U, Pu)혼합핵연료 및 사용후 핵연료의 비열 자료들이 분석되었다. 사용 후 핵연료의 경우 모의 핵연료의 비열로 대신하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.1012-1015
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• 2001

The purpose of this paper is to evaluate the specific cutting energy characteristics during turning SM45C steel. Using the orthogonal array method the specific cutting energy has been predicted. And the significance of the equation is checked by ANOVA test. Predicted values of specific cutting energy are well concide with the measured ones. When the feed rate becaomes larger than 0.5mm/rev, predicted specific cutting energy increases.

• Tribology and Lubricants
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• 제17권4호
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• pp.297-306
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• 2001

Under the condition of variable density and specific heat, maximum pressure, maximum temperature, bearing load, friction and side leakage in high-speed journal bearing operation are examined within some degree of Journal misalignment. The results are compared with the calculation results under the conditions of constant density and specific heat, and variable density and constant specific heat. It is found that the condition of variable density and specific heat play important roles in determining friction and load of Journal bearing at high speed operation.

• Molecules and Cells
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• 제40권3호
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• pp.169-177
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• 2017

Tissue-specific transcription is critical for normal development, and abnormalities causing undesirable gene expression may lead to diseases such as cancer. Such highly organized transcription is controlled by enhancers with specific DNA sequences recognized by transcription factors. Enhancers are associated with chromatin modifications that are distinct epigenetic features in a tissue-specific manner. Recently, super-enhancers comprising enhancer clusters co-occupied by lineage-specific factors have been identified in diverse cell types such as adipocytes, hair follicle stem cells, and mammary epithelial cells. In addition, noncoding RNAs, named eRNAs, are synthesized at super-enhancer regions before their target genes are transcribed. Many functional studies revealed that super-enhancers and eRNAs are essential for the regulation of tissue-specific gene expression. In this review, we summarize recent findings concerning enhancer function in tissue-specific gene regulation and cancer development.

• Ocean and Polar Research
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• 제39권4호
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• pp.257-267
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• 2017

Although Pacific mackerel (Scomber japonicus) is an important commercial species in Korea, its recruitment mechanism remains largely unknown. Diel vertical positioning of larvae in the water column, which is affected by their specific gravity and the surrounding water density, may help to provide an understanding on recruitment success through predator avoidance and prey availability. The specific gravity measurement on Pacific mackerel eggs and larvae would seem to be essential information necessary to learn about the transport process from spawning to nursery grounds, and consequently the recruitment success. Eggs were artificially fertilized, and larvae were fed with rotifer when their mouths opened 3-4 days after hatching. We conducted the experiment using a density gradient water column to measure the ontogenetic changes in specific gravity from fertilization to 10 days after hatching. Egg specific gravity was stable during most of the embryonic period, but a sudden increase to $1.0249g\;cm^{-3}$ happened just before hatching. However, the specific gravity of newly hatched larvae was much lighter ($1.0195g\;cm^{-3}$), and specific gravity tended to increase continuously after hatching. Comparison of specific gravity with seawater density reveals that eggs and newly hatched larvae can float in the surface layer of the ocean. For the later period of the experiment, the specific gravity showed a cyclic diel pattern: the highest in the evening while the lowest at dawn. The fullness of larval stomach may be responsible for the observed differences in specific gravity, because stomach fullness was lower (40-60%) at midnight, and higher (80-85%) in evening. The diel pattern of specific gravity might provide clues regarding how larvae match the diel vertical migration of prey organisms.

• 한국작물학회지
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• 제53권4호
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• pp.434-439
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• 2008

The amount of salt to make seed sorting solution of the specific gravity of 1.13 was reconsidered and determined as 3.8 kg salt in 18 L water, which is lower amount than currently used. Five rice cultivars were examined. Percent germination and seedling emergence were not similar. Seedling emergence rate of Japonica varieties, Nampyungbyeo and Daerypbyeo-1 were 87% and 95% under specific gravity of 1.13, respectively. Seedling emergence rate of Tongil type variety, Dasanbyeo was as high as 67% in specific gravity of 1.06. Seedling emergence rate of waxy rice, Hwasunchalbyeo and Aranghangchalbyeo were examined. Seedling emergence rate was 94% in both cultivars in specific gravity of 1.04. Seedling emergence rate was same in specific gravity of 1.08 which is generally used for selecting seed currently. Early growth (plant height, leaf number, and dry weight) were not significantly different by specific gravity within species. In all cultivars except waxy rice, highest seedling emergence rate was observed in specific gravity of 1.13 which is currently used for selection and decreased as specific gravity is lowed. However, considering total amount of seeds in each group of specific gravity, amount of seed in lower specific gravity group is relatively small and total seedling emergence rate within variety dose not show big difference. However, if seeds with low speicific gravity are produced due to the bad grain filling condition and consequently total seed content of low specific gravity increases, results will be differnt. Reduction in total growth and yield could occur. It will be important to comply with the seed sorting criterion of 1.13 for Japonica, 1.06 for Tongil, and 1.04 for waxy rice variety to ensure the maximum rice growth and yield.

• 생명과학회지
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• 제22권2호
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• pp.209-219
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• 2012

눈조직의 젖산탈수소효소(LDH, EC 1.1.1.27) eye-specific $C_4$ 동위효소의 특성을 native-PAGE, Western blotting, 면역침강반응 및 효소 역학을 이용하여 연구하였고, LDH eye-specific $C_4$ 동위효소의 활성을 측정하는 조건을 제시하였다. 파랑볼우럭(Lepomis macrochirus)과 큰입우럭(Micropterus salmoides) 눈조직의 세포기질에서 LDH eye-specific $C_4$ 동위효소가 확인되었으며 $B_4$ 동위효소보다 $A_4$ 동위효소에 유사하였다. 파랑볼우럭 눈조직의 LDH/CS는 9월에 증가하여 혐기적 대사가 높게 이루어졌다. 파랑볼우럭과 큰입우럭 눈조직 미토콘드리아 LDH의 전기영동상은 세포기질 LDH와 유사하였다. 눈조직의 LDH eye-specific $C_4$ 동위효소는 Preparative native-PAGE에 의해 정제되었다. 파랑볼우럭과 큰입우럭의 LDH eye-specific $C_4$ 동위효소의 활성은 피루브산 0.2 mM과 0.1 mM 이상의 농도에서 각각 감소되었고, 피루브산 10 mM에서 5.2%, 15.8% 활성이 남아 저해 정도가 크게 나타났다. 그리고 눈조직의 LDH 활성도 젖산 22 mM과 24 mM 이상의 농도에서 각각 감소되어졌다. 파랑 볼우럭 eye-specific $C_4$ 동위효소의 $Km^{PYR}$는 0.088 mM, 큰입우럭 eye-specific $C_4$ $Km^{PYR}$는 0.033 mM였으며, 세포기질과 미토콘드리아 eye-specific $C_4$ 동위효소는 ${\alpha}$-ketobutyric acid에서 활성이 높게 나타났다. 눈조직과 eye-specific $C_4$ 동위효소의 활성은 피루브산 0.5 mM과 Tris-HCl 완충액, pH 7.5에서 측정하는 것이 적합한 것으로 확인되었다. 실험 결과, 큰입우럭 LDH eye-specific $C_4$ 동위효소는 파랑볼우럭 LDH eye-specific $C_4$보다 피루브산에 대한 친화력이 큰 것으로 확인되었고, 더 낮은 피루브산의 농도에서 최대 활성에 이르고, 더 높은 젖산의 농도에서 최대 활성을 나타냈다. 따라서 LDH eye-specific $C_4$ 동위효소에 의해 생성된 에너지가 포식 행동의 초기 반응에 사용되는 것으로 사료된다.

• 생명과학회지
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• 제21권11호
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• pp.1565-1572
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• 2011

쥐노래미(Hexagrammos otakii) 눈 조직의 젖산탈수소효소(EC 1.1.1.27, lactate dehydrogenase, LDH) eye-specific $C_4$ 동위효소를 affinity chromatography 및 continuous-elution electrophoresis system으로 정제하였다. 정제된 eye-specific LDH $C_4$ 동위효소의 분자량은 154.8 kDa이었다. 효소반응의 최적 pH는 8.5로 나타났다. 피루브산을 기질로 하였을 때 eye-specific LDH $C_4$ 동위효소의 $K^{PYR}_m$ 값은 $1.88{\times}10^{-5}$ M로 나타났다. 본 실험결과 eye-specific LDH $C_4$ 동위효소의 활성 측정 시 pH를 고려해야만 하고 eye-specific LDH $C_4$ 동위효소는 LDH A4 동위효소보다 피루브산에 대한 기질결합친화성이 큰 것으로나타났다. 생성된 eye-specific LDH $C_4$ 동위효소에 대한 항체는 사람에서의 병증진단 및 어류에서의 비교생리학적 연구에 폭 넓게 사용될 것이라고 생각된다.

• 한국도서관정보학회지
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• 제14권
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• pp.39-69
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• 1987

The purpose of this research is to analyze the differences between literature (Belles-letters) class in DDC 19 and literature class in KDC 3. The results of the study can be summarized as follows : 1. The section of philosophy and theory of literature in DDC was subdivided according to the properties as including subsection of theory of criticism but KDC didn't subdivide this section. 2. In DDC, the subsections of 'rhetoric in specific languages' and 'rhetoric of specific kinds of composition' in rhetoric section was established and can subdivide according to each languages and subjects. These considerations can be useful as compared with KDC. 3. In DDC, collections or criticism of several literatures in specific forms can be more subdivide according to specific aspects or features dealing with in the collections or criticism by a n.0, pplying Table 3-A when specified more than the literary form. 4. Reviewing a notational rank to be assigned in literatures of specific languages, Latin literature and Classical Greek literature to be ranked in division in DDC was established as subsection in KDC to treat them as literatures of minor languages. 5. The DDC can sometimes a n.0, pply, in literatures of all languages, the notations of Table 3 to be subdivided again as specific kinds of literary forms, but KDC subdivided literary forms as specific kinds of each forms in only Korean, Chinese, Japanese literature. 6. In DDC, even literatures of minor languages are provided with 'the period table for the specific literature' under each literature of specific languages in schedules and these period tables can be a n.0, pplied a n.0, ppropriately, but period numbers in KDC was established in only Korean, Chinese, Japanese literature. 7. The optional use of letter prefixes or special numbers such as 828.99 to distinguish literatures of countries other than the "mother country" which makes the use of period tables feasible, but the KDC can only use to distinguish without the function of dividing a period such as DDC. 8. According to a n.0, pplying Table 3 and 3-A also in literatures of specific languages(810-890), a literature of specific languages, a specific literary form in literature of specific languages and a literature or literary form of specific period, in case of a n.0, pplying 'form divisions 08-09', can subdivide again by a specific aspect or feature dealing with in the works when specified. 9. For grasping the rate of subdividing, after selecting several sample-titles in literary field, they classified by DDC and KDC and gave a definite score in accordance with analytic small subjects. According to the results, the rate of subdividing in literature class of KDC is proved as less 22.8% than DDC. than DDC.

• 생명과학회지
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• 제14권4호
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• pp.708-715
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• 2004

칠성장어(Lampetra japonica) 간조직 젖산탈수소효소(EC 1.1.1.27, lactate dehydrogenase, LDH) 동위효소는 affinity chromatography에서 buffer를 유입한 후 용출된 분획에서 정제되었다. 대구(Gadus macrocephalus)의 liver-specific $C_4$동위효소는 열처리한 후 affinity chromatography하여 NAD+ 를 함유한 buffer에서 용출되기 시작하여 buffer를 유입한 후 $B_4$ 동위효소와 함께 용출되어, DEAE-Sephacel chromatography에 의해 정제되었다. 대구 간조직에서 열에 대한 안정성은$C_4$$B_4$$A_4$ 동위효소의 순서로 나타났다. Chromate-focusing에 의해 정제한 칠성장어 간조직의 pH 7.45 분획의 LDH 동위효소는 정제된 간조직 LDH보다 피루브산에 의한 기질저해도가 컸다. 칠성장어 간조직 LDH의 최적 pH는 7.5, liver-specific $C_4$동위효소는 pH 8.5였다. 칠성장어 간조직 LDH는 항원-항체반응에서 꺽지 $A_4$ 항체와 liver-specific $C_4$ 항체의 순서로 반응하였고 eye-specific $C_4$ 항체와는 반응 정도가 낮았다. 따라서 칠성장어 간조직 LDH는 하부단위체 A와 liver-specific $C_4$의 구조와 유사하게 진화되었으며, 하부단위체 C 는 진화속도가 매우 빠른 것으로 확인되었다. 칠성장어 간조직의 LDH는 단일 동위효소가 아니라, 하부단위체 A, B 및 C로 구성된 동위효소들인 것으로 사료된다.