• Journal of the Chungcheong Mathematical Society
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• v.25 no.2
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• pp.201-215
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• 2012

In this paper, we prove the stability in random normed spaces via fixed point method for the functional equation $f(x+y+z+w)\;+\;2f(x)\;+\;2f(y)\;+\;2f(z)\;+\;2f(w)\;-\;f(x+y)\;-\;f(x+z)\;-\;f(x+w)\;-\;f(y+z)\;-\;f(y+w)\;-\;f(z+w)=0$.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.1-6
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• 2006

Saccharomyces cerevisiae Dna2 helicase/endonuclease plays an essential role in removing DNA primers during Okazaki fragment processing in eukaryotic DNA replication. Genome-wide scale co-immunoprecipitation experiments predicted that Dna2 interacts with a novel protein YHR122W (1). In this study, we observed that overexpression of YHR122W gene suppressed the temperature-sensitive phenotype of $dna2\Delta405N$ mutation. To investigate direct interaction between these two proteins, a histidine-tagged recombinant YHR122W protein was expressed and purified from E. coli. Physical interaction between the purified YHR122W and Dna2 proteins was detected by enzyme-linked immunosorbent assays. Further more, the complex formation was most efficient at physiological salt concentration, 150 mM NaCl. The genetic and physical interactions between YHR122W and Dna2 shown in this study suggest that the biological functions of these two proteins may be closely related each other.

• Toxicological Research
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• v.26 no.3
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• pp.171-175
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• 2010

The human genome contains approximately 13 orphan cytochrome P450 (P450, CYP) genes, of which the apparent function or substrate has not been identified. However, they seem to possess their own biological relevance in some tissues or developmental stages. Here, we characterized the heterologously expressed CYP2W1, an orphan P450 enzyme. The recombinant CYP2W1 protein containing a $6{\times}$(His)-tag at Nterminus has been expressed in Escherichia coli and purified. Expression level of CYP2W1 holoenzyme was around 500 nmol P450 holoenzyme per liter culture medium. The reduced CO difference spectrum of CYP2W1 showed a maximum absorption at 449 nm. CYP2W1 indicated the significant induction to bioactivate Trp-P-1, MeIQ, and IQ in E. coli DJ701 tester strain. However, the bioactivation of B[$\alpha$]P, and NNK by CYP2W1 was relatively low. The model structure of CYP2W1 suggested the characteristic P450 folds with the lengths and orientations of the individual secondary elements. The F-G loop is situated on the distal side of heme to accommodate the flexibility of active site of CYP2W1. These studies can provide useful information for the finding of its biological roles and structure-function relationships of an orphan CYP2W1 enzyme.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.497-500
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• 2007

지열류량은 지열자원 개발 시 지열 이상대를 찾는데 있어서 중요한 자료로 사용된다. 우리나라의 지체구조별 지열류량 평균은 경기육괴 66 $mW/m^2$, 옥천습곡대 65 $mW/m^2$, 영남육괴 60 $mW/m^2$, 경상분지 72 $mW/m^2$, 연일분지 75 $mW/m^2$이다. 이러한 대륙 내의 지표 지열류량은 상부 지각내의 방사성 동위원소 붕괴에 의한 열생산율(${\sim}40%$)과 하부지각 및 상부맨틀에서부터 전도되어 올라온 지열류량(${\sim}60%$)으로 설명할 수 있다. 따라서 지열류량의 결정에 있어서 열생산율의 정보는 중요한 부분을 차지한다. 열생산율은 지각 내에 존재하는 주요 방사성 동위 원소인 U, Th, K의 붕괴열에 의한 것이며, 열생산율의 측정은 gamma-ray log 자료를 이용하는 방법과 화학분석을 통한 방법이 있다. 이 연구에서는 두 가지 방법을 이용하여 총 123개(화강암 86개, 편마암 37개) 지점에서의 열생산율을 산출하였다. 화강암의 열생산율 평균은 2.15 ${\mu}W/m^3$이며, 편마암의 열생산율 평균은 2.22 ${\mu}W/m^3$로 나타났다. 지체구조별 열생산율의 평균은 경기육괴 2.52 ${\mu}W/m^3$, 옥천습곡대 2.16 ${\mu}W/m^3$, 영남육괴 2.35 ${\mu}W/m^3$, 경상분지 2.01 ${\mu}W/m^3$로 나타났다. 지체 구조별 열생산율과 지열류량의 상관성 분석에서 우리나라의 경우 지열류량이 높은 지역에서 열생산율이 낮은 경향을 보인다. 따라서 열생산율이 지표 지열류량을 결정하는데 있어서 가장 중요한 요소가 아님을 확인할 수 있다.

• Analytical Science and Technology
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• v.15 no.1
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• pp.15-19
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• 2002

The pretreatment of tungsten added $BaTiO_x$ ceramics was performed to improve the recovery of Ba, Ti and W. $BaTiO_x$ ceramics were digested with HF : HCl ( 1 : 2 ) mixture in an acid digestion bomb at $220^{\circ}C$ for 3 hrs. The concentration of Ba, Ti and W were determined by ICP-AES. Recoveries of Ba, Ti and W were 99.6%, 99.8% and 99.2%, respectively. And their C.V. values were 1.02%, 0.73% and 1.79%. Using this method, the analytical results of Ba, Ti and W for a real sample were obainted to be 25.9% (w/w), 38.8% (w/w) and 3.31% (w/w), respectively.

• Food Science and Preservation
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• v.10 no.3
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• pp.360-364
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• 2003

This study was conducted to investigate the preparation possibility of Beni-koji by Monascus pilosus using dried soybean curd residue(Biji). The additional effect of water(0-50％), glucose(0-10％, w/w), monosodium glutamate(0-0.l％, w/w) and citrus peel water extracts (0-0.5％, v/w) on the pigment and monacolin K content of the Biji Beni-koji were examined. Optimal added amounts of water was 20％ of dried Biji. The highest pigment content(OD at 500 nm) of Biji Beni-koji was 1.06 in 10％ glucose, 2.26 in 0.01％ monosodium glutamate and 2.61 in 0.4％ citrus peel water extracts. The content of monacolin K in the Biji Beni-koji added with 10％ glucose, 0.01％ monosodium glutamate and 0.4％ citrus peel water extracts showed 96.38 mg％(w/w), 118.25 mg％(w/w) and 104.50 mg％(w/w), respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.320-325
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• 2003

The purpose of study was to investigate the effect of carbon dioxide laser on demineralization inhibition and rehardening of primary tooth enamel according to its power and irradiation time. 2mm diameter circle on the primary enamel surface was irradiated by defocused $10.6{\mu}m$ superpulse carbon dioxide laser at 6 Watt 2 seconds or at 3 Watt 8 seconds, before or after demineralization by Coca-Cola for 24 hours. Enamel surface change was measured by the Diagnodent. The results were analyzed with the former study results of 3 Watt 4 seconds and 6 Watt and 4 seconds. Diagnodent scores increased significantly after demineralization of irradiated enamel at 6W 2s or 3W 8s (P<0.05). Among the four groups, only 6W 4s group showed obvious demineralization inhibition effect. Diagnodent scores reduced significantly after 6W 2s or 3W 8s irradiation of demineralized enamel(P<0.05). Among the four groups, 6W 4s showed nearly complete rehardening effect, and the other groups showed partial effect. Tooth discoloration only occurred at 6W 4s. It seemed that caries inhibition and tooth discoloration depend on laser power more than total irradiation energy.

• Animal cells and systems
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• v.6 no.2
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• pp.167-170
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• 2002

The long terminal repeats (LTRs) of human endogenous retrovirus (HERV) have been found to be coexpressed with sequences of closely located genes. It has been suggested that the LTR elements have contributed to the structural change or genetic variation of human genome connected to various diseases and evolution. We examined the HERV-W LTR elements in various cancer cells (2F7, A43l , A549, HepG2, MIA-PaCa-2, PC-3, RT4, SiHa, U-937, and UO-31). Using genomic DNA from the cancer cells, we performed PCR amplification and identified twelve new HERV-W LTR elements. Those LTR elements showed a high degree of sequence similarity (88-99％) with HERV-W LTR (AF072500). A phylogenetic tree obtained by the neighbor-joining method revealed that HERV-W LTR elements could be mainly divided into two groups through evolutionary divergence. Three HERV-W LTR elements (RT4-2, A43l-1, and UO3l-2) belonged to Group 1, whereas nine LTR elements (2F7-2, A549-1, A549-3, HepG2-3, MP2-2, PC3-1, SiHa-8, SiHa-10, and U937-1) belonged to Group 11. Taken together, our new sequence data of the HERV-W LTR elements may contribute to an understanding of tissue-specific cancer by genomic instability of LTR integration.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.10
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• pp.1540-1544
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• 2003

This study chiefly aimed to ascertain the effect of age at weaning on caecal content characteristics, post-weaning performance and health of rabbits. A secondary aim was to study the effect of dietary restriction on performance and health of rabbits. After delivery, 30 litters of 8 pups each, were housed in separate cages. Fifteen litters were weaned 24 days from birth (group W 24) while the other 15 were weaned at 28 days (group W28). After weaning, 53 rabbits of group W24 and 56 of group W28 were fed ad libitum (group LIB), while 53 rabbits of group W24 and 57 of group W28 were restricted (group RES). All the rabbits were kept in individual cages. Fourteen other rabbits of groups W24 (7 fed ad libitum and 7 restricted) and 7 of group W28 were sacrificed to obtain data regarding caecum weight and caecal content. Age at weaning affected neither the state of health nor the final live weight. In comparison with those of group W28, the rabbits weaned at 24 days had a lower daily gain until 35 days of age but gain was higher subsequently. From the 28th day, however, the feed intake and the feed conversion ratio of the group W24 rabbits were always better than those of W28. The restricted diet until 42 days resulted in a lower weight both at 42 days (1,078 vs. 1,164 g) and at 70 days (2,192 vs. 2,294 g). Indeed, from the 42nd day, despite receiving feed ad libitum the rabbits of the restricted group continued to ingest less feed (120.8 vs. 127.2 g) than those of the ad libitum group, and had a slightly lower daily gain (39.8 vs. 40.3 g). The measurements carried out on the caecum highlighted significant differences among the groups in caecal content (33.1 vs. 31.7 vs. 25.3 g respectively for groups W24LIB, W28 and W24RES), for total volatile fatty acids (53.2 vs. 50.6 vs. 44.5 mmol/l respectively for groups W24LIB, W28and W24RES) for ammonia (7.0 vs. 7.2vs 8.8 mmol/l respectively for groups W24LIB, W28 and W24RES), for propionate (5.7 vs. 6.3 vs. 8.1% respectively for groups W24LIB, W28 and W24RES) and for propionate/butyrate (0.33 vs. 0.36 vs. 0.49 respectively for groups W24LIB, W28 and W24RES).

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.854-863
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• 2021

Weaning induces physiological changes in intestinal development that affect pigs' growth performance and susceptibility to disease. As a posttranscriptional regulator, microRNAs (miRNAs) regulate cellular homeostasis during intestinal development. We performed small RNA expression profiling in the small intestine of piglets before weaning (BW), 1 week after weaning (1W), and 2 weeks after weaning (2W) to identify weaning-associated differentially expressed miRNAs. We identified 38 differentially expressed miRNAs with varying expression levels among BW, 1W, and 2W. Then, we classified expression patterns of the identified miRNAs into four types. ssc-miR-196a and ssc-miR-451 represent pattern 1, which had an increased expression at 1W and a decreased expression at 2W. ssc-miR-499-5p represents pattern 2, which had an increased expression at 1W and a stable expression at 2W. ssc-miR-7135-3p and ssc-miR-144 represent pattern 3, which had a stable expression at 1W and a decreased expression at 2W. Eleven miRNAs (ssc-miR-542-3p, ssc-miR-214, ssc-miR-758, ssc-miR-4331, ssc-miR-105-1, ssc-miR-1285, ssc-miR-10a-5p, ssc-miR-4332, ssc-miR-503, ssc-miR-6782-3p, and ssc-miR-424-5p) represent pattern 4, which had a decreased expression at 1W and a stable expression at 2W. Moreover, we identified 133 candidate targets for miR-196a using a target prediction database. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed that the target genes were associated with 19 biological processes, 4 cellular components, 8 molecular functions, and 7 KEGG pathways, including anterior/posterior pattern specification as well as the cancer, PI3K-Akt, MAPK, GnRH, and neurotrophin signaling pathways. These findings suggest that miRNAs regulate the development of the small intestine during the weaning process in piglets by anterior/posterior pattern specification as well as the cancer, PI3K-Akt, MAPK, GnRH, and neurotrophin signaling pathways.