• 비파괴검사학회지
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• 제23권3호
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• pp.220-226
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• 2003

본 연구에서는 선박 용접구조물의 피로균열 발생 여부와 균열의 진전 상황을 실시간으로 모니터링하기 위한 기초 연구단계로서 선박의 전형적인 용접형태인 필렛용접부(fillet welded joint)의 피로시험에 대한 음향방출(Acoustic Emission, AE)기법의 적용성을 검토하였다. 필렛용접부의 피로시험에서 균열의 발생과 진전, 위치를 검출하기 위하여 AE 카운트(ring down count)와 위치표정(source location)등을 이용하였다. 시험결과 용접 토우(toe)부의 표면균열(surface crack)이 관통균열(through crack)로 발전하기 전까지의 AE 신호는 비교적 미약하게 나타났으나 균열의 발생시점과 위치를 카운트-위치표정으로 어느 정도 추정 가능함을 확인하였다. 표면균열이 브라켓의 두께방향으로 관통한 시점에서는 AE 카운트의 양이 급격히 증가하였으며 카운트-위치표정, 이벤트(event)-위치표정으로 균열의 위치와 발생시점을 명확하게 확인할 수 있었다. 또한 AE 위치표정과 클러스터(cluster) 기능을 이용하여 균열발생 위치 이외의 영역에서 검출된 신호는 잡음에 기인한 것으로 추정할 수 있었다.

• Journal of Ginseng Research
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• 제39권3호
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• pp.265-273
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• 2015

Background: Cancer has emerged as a major health problem globally as a consequence to the increased longevity of the population, changing the environment and life style. Chemoprevention is a new and promising strategy for reducing cancer burden. Recently, some natural products have been identified for their chemopreventive activity to reduce the cancer incidence. Ginseng is known for its potential to treat various ailments in human beings. The present study was designed to explore the anticancer and antioxidative potential of Panax ginseng against chemical-induced skin carcinogenesis in mammals. Methods: Skin tumors were induced in Swiss albino mice by a single topical application of 7,12-dimethylbenz(a)anthracene ($100{\mu}g/100{\mu}L$ acetone) and, 2 wks later, promoted by repeated applications of croton oil (thrice in a wk in 1% acetone) till the end of the experiment (i.e., 16 wk). Hydroalcoholic ginseng root extract at a dose of 25 mg/kg body weight/d was orally administered at the periinitiation, postinitiation, and peri-post-initiation stages. Results: Ginseng root extract treatment caused a significant reduction in tumor incidence, cumulative number of tumors, tumor yield, and tumor burden, as compared to the 7,12-dimethylbenz(a)anthracene-croton oil-treated control group. Further, biochemical assays revealed a significant enhancement in the levels of reduced glutathione, superoxide dismutase, catalase, vitamin C, and total proteins but a significant reduction in lipid peroxidation levels in both the liver and skin with ginseng root extract treatment, as compared to carcinogen-treated control group. Conclusion: These results suggest that P. ginseng has the potential to become a pivotal chemopreventive agent that can reduce cancer in mammals.

• 한국작물학회지
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• 제27권1호
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• pp.72-77
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• 1982

고려인삼의 삽목에 의한 영양번식방법을 개발하고저 완전히 전엽된 3매 소엽을 부착한 묘삼경을 삽수로 취하여 NAA의 처리농도가 이들 삽수의 발근에 미치는 영향을 조사하는 한편 삽목용토 및 삽목방법이 발근 및 발근후의 근생장에 미치는 영향을 조사하였다. NAA는 삽목후 관수시 NAA용액으로 관수하였던 바 1.0ppm 용액의 관수가 발근율 및 발근후의 근생장에 가장 효과적이었으며 또한 삽목용토로는 부엽토와 모래의 혼합토가 가장 이상적이었다. 삽목후 삽수에 부착된 엽에서의 증산을 억제하고 삽수의 고사를 방지하기 위해서는 Acril film으로 만든 덮개로 삽수의 지상부를 씌워 주는 것이 삽수의 발근에는 물론 특히 발근후의 근생육에 효과적이었다. 한편 5매의 소엽이 부착되어 있는 2년생 인삼의 엽병을 삽수로 하여 부엽토와 모래의 혼합토에 삽목하고 1.0ppm의 NAA 용액을 관수하였던 바 역시 양호한 발근율과 근생장을 보였는데 근의 생장량은 묘삼에서 취한 경삽보다는 약간 부진하였다.

• Preventive Nutrition and Food Science
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• 제13권3호
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• pp.157-165
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• 2008

Cancer-preventive effects of ethanol extract of elm tree root (EEE) were investigated. In the in vitro cytotoxicity assay, colon cancer cells were incubated with a chloroform fraction of EEE (CF-EEE). CF-EEE significantly inhibited the proliferation of cells and induced apoptotic cell death in a dose-dependent manner. For the assessment of chemopreventive efficacy in vivo, male F344 rats were fed with EEE (0.5 or 1%) in diet for 8 weeks, and were subcutaneously injected with 1,2-dimethylhydrazine (DMH) to induce colonic aberrant crypt foci (ACF). EEE (0.5 and 1%) significantly decreased both the numbers of AC (1191.1/colon) and ACF (529.3/colon) induced by DMH. In addition, in the Western blot analysis on the colonic mucosa, administration of EEE triggered expression of caspase-3, a key factor of an apoptotic cascade. These results suggest that extract of elm tree root may have potential chemopreventive principles that lead to apoptosis of cancer cells, and thereby suppress colorectal carcinogenesis during the initiation stage.

• 대한소아치과학회지
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• 제29권4호
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• pp.607-617
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• 2002

연령과 치아 발육상태 단계와의 상관관계, 치아의 발육에 따른 치아의 이동상태를 평가하기 위하여 최근 5년 이내에 경북대학교 병원에 내원한 아동(남아 446명, 여아 326명)의 파노라마 방사선사진을 대상으로 하여, Moorrees의 기준에 의하여 하악 영구치아의 발육단계를 평가한 후, 발육단계와 연령, 치조골내 치아의 위치를 평가하여 다음과 같은 결론을 얻었다. 치아의 발육시기는 치관이 완료될 때까지 남, 여의 차이가 없었으나, 치근형성이 되면서 부터는 남아보다 여아에서 더 빨리 발육되는 경향을 나타내었다. 치관형성의 완료시점의 평균연령은 남아 여아 각각에서 중절치 3.71, 4.05세, 측절치 4.44, 4.60세, 견치 5.35, 5.11세, 제1소구치 6.62, 6.36세, 제2소구치 7.36, 7.17세, 제1대구치 3.51, 3.69세, 제2대구치 7.90, 7.64세 이었고, 치근단이 폐쇄되기 전단계인 $A_{1/2}$는 중절치 8.70, 8.18세, 측절치 9.55, 8.99세, 견치 12.48, 11.60세, 제1소구치 12.30, 12.01세, 제2소구치 12.19, 12.26세, 제1대구치 912, 8.87세, 제2대구치 12.59, 12.45세 이었다. 치조골내의 교두점 위치는 치관형성 완료시까지는 거의 변화가 없었으나, 치근이 형성됨에 따라 빠르게 교합평면을 향해 이동하였고, 치근형성 완료단계(Rc)에서 다시 움직임 없이 정체되었다. 치근단의 위치는 치관형성 시작부터 치근 1/4 형성 시까지 일정한 위치에 유지되었으나, 그 후에 급격하게 교합면 쪽으로 이동하였고, 치근 3/4 형성시점부터 비교적 일정한 위치에 유지되었다. 치아의 석회화가 시작되는 초기의 치배 위치는 견치가 가장 하방에 위치하였으며, 그 다음이 제2소구치, 제1소구치, 측절치 제2대구치, 제1대구치 순이었고, 중절치가 가장 상방에 위치하였다.

• 한국산림과학회지
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• 제79권1호
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• pp.26-32
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• 1990

기내(器內)에서 배양(培養)된 5수종(樹種)의 Populus 류(類)(P. davidiana, P. maximowiczii, P. nigra, P. alba ${\times}$ P. glandulosa, P. nigra ${\times}$ P. maximowiczii)의 줄기를 Aluminium-EDTA가 0, 0.1, 0.2, 0.5, 1.0mM씩 첨가(添加)된 배지(培地)에 배양(培養)시켜 뿌리, 줄기, 잎의 생육(生育)상태를 조사(調査)하여 aluminium 내성(耐性)을 비교 분석하였다. 수종간(樹種間) Aluminium내성(耐性)의 차이(差異)는 비교적(比較的) 심(甚)하게 나타났고, 조사(調査)한 5수종중(樹種中) 사시나무가 가장강한 내성(耐性)을 지닌것으로 나타났다. Al-EDTA가 낮은 농도(濃度)로 첨가(添加)된 배지(培地)에서는 줄기와 뿌리생장에 촉진효과를 나타내는 종도 있었다. 1.0mM의 고농도(高濃度)에서는 사시나무 이외의 수종(樹種)에서는 발근(發根)이 억제되었다. 양버들, 황철, 현사시와 같은 내성(耐性)이 약(弱)한 수종(樹種)에서는 0.1mM의 낮은 농도(濃度)에서도 잎과 줄기에 형태적(形態的)인 변이현상이 나타났다. 양황철은 그 양친(兩親)인 양버들이나 황철보다 줄기생장(生長)에서 내성(耐性)이 증가했다.

• 대한조선학회논문집
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• 제41권6호
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• pp.40-47
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• 2004

The influence of heat input on fracture toughness was investigated in SAW weldments, which were prepared at two different welding conditions in API 2W Gr.50 and EN10225 5420. By examining the fracture initiation point, refined areas(ICHAZ and SCHAZ) in weld metal was identified as local brittle zone, in which M-A constituents and coarsed grain size were observed. Impact values showed the most significant difference at root portion, and CTOD transition temperature was related with impact values obtained at root portion. Hardness values in refined area were less than columnar microstructure about 20 HV5.

• 식물조직배양학회지
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• 제25권2호
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• pp.89-93
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• 1998

Tomato phenylalanine ammonia-lyase 5 (tPAL5) was identified that alternate initiation sites were utilized differentially in response to environmental stimuli (Lee et al, 1992b). In this study, we tried to look into tissue -or cell- specific expression pattern of tPAL5 gene by fusing with ${\beta}-glucuronidase$ (GUS) gene in transgenic tobacco plants. In transgenic plants, root and stem extracts contained 8~12 fold higher levels of GUS activity than petiole or leaf tissue while the highest levels of induction was observed from leaf tissue by mechanical wounding (5~11 fold). In trans-sections of stems and petioles, GUS activity was restricted to phloem cells(outer region) of developing vascular bundle and mainly at apical tip region in the root tissues. The levels of GUS activity was drastically reduced (10~12 fold reduction) when the 5'-upstream region of tPAL5 gene (-1151bp from ATG codon) was deleted up to -665. The levels of GUS expression, however, raised up by 6~8 fold when deleted up to -455. Therefore, we conclude that there are positive cis-elements at the region -1151 to -1008 and at -455 to -195 while the negative cis-element is at -1008 to -455.

• 농업생명과학연구
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• 제43권6호
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• pp.59-65
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• 2009

Combinations of plant growth regulators, darkness treatments, and the order of expanding leaves for explants were evaluated for optimizing in vitro shoot regeneration rate of 'Whangkeumbae' pear. In a MS medium, supplemented with $8.88{\mu}M$ 6-benzylaminopurine (BA) and $0.49{\mu}M$ indole-3-butyric acid (IBA), green foci were observed on the surface of the callus 8 days after culture initiation. Some adventitious buds were later induced from those green foci, resulting in the appearance of normal shoots. In a medium containing $22.20{\mu}M\;BA$, the surface of the callus became compact and greenish, and many adventitious buds were formed over the entire area of the callus surface. When comparing BA concentration via histological observation, the section which had been treated with $22.20{\mu}M\;BA$ exhibited closer cell aggregation than those with $8.88{\mu}M\;BA$. The darkness treatment enhanced the formation of adventitious shoots for up to 3 weeks. The youngest two expanding leaves, proximal to the shoot apex, were proved to be the most regenerative, and yielded the highest shoot number per regenerating leaf. A fourth strength MS medium, which was supplemented with $0.54{\mu}M\;NAA$, yielded good quality plantlets, with regard to root number and root length.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2301-2305
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• 2013

Ardisia crispa (Family: Myrsinaceae) is an evergreen, fruiting shrub that has been traditionally used as folklore medicine. Despite a scarcity of research publications, we have succeeded in showing suppressive effects on murine skin papillomagenesis. In extension, the present research was aimed at determining the effect of a quinone-rich fraction (QRF) isolated from the same root hexane extract on both initiation and promotion stages of carcinogenesis, at the selected dose of 30 mg/kg. Mice (groups I-IV) were initiated with a single dose of 7,12-dimethylbenz(${\alpha}$)anthracene (DMBA, $100{\mu}g/100{\mu}l$) followed by repeated promotion of croton oil (1%) twice weekly for 20 weeks. In addition, group I (anti-initiation) received QRF 7 days before and after DMBA; group II (anti-promotion) received QRF 30 minutes before each croton oil application; group III (anti-initiation/promotion) was treated with QRF as a combination of group I and II. A further two groups served as vehicle control (group V) and treated control (group VI). As carcinogen control, group IV showed the highest tumor volume ($8.79{\pm}5.44$) and tumor burden ($3.60{\pm}1.17$). Comparatively, group III revealed only 20% of tumor incidence, tumor burden ($3.00{\pm}1.00$) and tumor volume ($2.40{\pm}1.12$), which were significantly different from group IV. Group II also showed significant reduction of tumor volume (3.11), tumor burden (3.00) and tumor incidence (11.11%), along with prominent increase of latency period of tumor formation (week 12). Group I, nonetheless, demonstrated marked increment of tumor incidence by 40% with prompted latency period of tumor formation (week 7). No tumor formation was observed in groups V and VI. This study provided clear evidence of inhibitory effects of QRF during promotion period which was in agreement with our previous findings. The mechanism(s) underlying such effects have yet to be elucidated.