• 한국초전도ㆍ저온공학회논문지
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• 제11권3호
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• pp.60-64
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• 2009

We investigated an operating characteristic of linear-type magnetic flux pump (LTMFP) as a current compensator under the various conditions. In order to explain the mechanism of the LTMFP, the magnetic behavior of superconducting Nb foil according to pumping actions should be understood. In this paper, the magnetic field analysis of superconducting Nb foil installed in LTMFP has been performed based on the three-dimensional finite element method (3D FEM). Through the simulation analysis, the normal spot region on the superconducting Nb foil is found to be enhanced swiftly over about 20 Hz. The simulated finding agreed with an analytical estimation based on the phenomenon of magnetic diffusion.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.175-177
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• 1996

This paper is studied on the numerical analysis of temperature distribution on the Nb-foil due to the eddy current under operating a superconducting power supply. The increase of rotating speed and magnetic flux above critical magnetic field lead to the temperature rising in the normal spot, the heat was distributed in the region of 30% distance from the center of the normal spot, but the most of the heat was transferred to LHe. Under operation of the sc power supply, the increase of rotation speed has the more influence on the temperature rising than that of magnetic flux. we can conclude that the totaling speed of normal spot is the main design consideration of the sc power supply, and get the optimal value of rotating speed.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.23-33
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• 2021

"China's Western Development Policy" has brought multiple opportunities to the development of tourism in Southwest China including Sichuan, Guizhou, Yunnan, Chongqing and Tibet. The 4 provinces and 1 municipality overall show a certain degree of accumulation effect and coordinated development in tourism due to their location, traffic and traditional economic cooperation. This study takes the Southwest China as the research object and utilized the spatial dislocation model and the tourism spatial misalignment index to estimate the mismatch degree between tourism resources and tourism income among provinces and try to find out the internal reason background. The results show that each of the five provinces has its own advantages in index of economy, tourism resources, human resource, and transportation, leading to differences in the center of gravity of the entire region in all aspects. In view of the results of spatial dislocation analysis, suggestions for improvement and optimization are put forward to promote the high-quality development of tourism in Southwest region. development.

• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6403-6409
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• 2013

Purpose: Biallelic germline variants of the 8-hydroxyguanine (8-OG) repair gene MYH have been associated with colorectal neoplasms that display somatic $G:C{\rightarrow}T:A$ transversions. However, the effect of single germline variants has not been widely studied, prompting the present investigation of monoallelic MYH variants and susceptibility to sporadic colorectal cancer (CRC) in a Chinese population. Patients and Methods: Between January 2006 and December 2012, 400 cases of sporadic CRC and 600 age- and sex-matched normal blood donors were screened randomly for 7 potentially pathogenic germline MYH exons using genetic testing technology. Variants of heterozygosity at the MYH locus were assessed in both sporadic cancer patients and healthy controls. Univariate and multivariate analyses were performed to determine risk factors for cancer onset. Results: Five monoallelic single nucleotide polymorphisms (SNPs) were identified in the 7 exon regions of MYH, which were detected in 75 (18.75%) of 400 CRC patients as well as 42 (7%) of 600 normal controls. The region of exon 1 proved to be a linked polymorphic region for the first time, a triple linked variant including exon 1-316 $G{\rightarrow}A$, exon 1-292 $G{\rightarrow}A$ and intron 1+11 $C{\rightarrow}T$, being identified in 13 CRC patients and 2 normal blood donors. A variant of base replacement, intron 10-2 $A{\rightarrow}G$, was identified in the exon 10 region in 21 cases and 7 controls, while a similar type of variant in the exon 13 region, intron 13+12 $C{\rightarrow}T$, was identified in 8 cases and 6 controls. Not the only but a newly missense variant in the present study, p. V463E (Exon 14+74 $T{\rightarrow}A$), was identified in exon 14 in 6 patients and 1 normal control. In exon 16, nt. 1678-80 del GTT with loss of heterozygosity (LOH) was identified in 27 CRC cases and 26 controls. There was no Y165C in exon 7 or G382D in exon 14, the hot-spot variants which have been reported most frequently in Caucasian studies. After univariate analysis and multivariate analysis, the linked variant in exon 1 region (p=0.002), intron 10-2 $A{\rightarrow}G$ (p=0.004) and p. V463E (p=0.036) in the MYH gene were selected as 3 independent risk factors for CRC. Conclusions: According to these results, the linked variant in Exon 1 region, Intron 10-2 $A{\rightarrow}G$ of base replacement and p. V463E of missense variant, the 3 heterozygosity variants of MYH gene in a Chinese population, may relate to the susceptibility to sporadic CRC. Lack of the hot-spot variants of Caucasians in the present study may due to the ethnic difference in MYH gene.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 전기설비
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• pp.55-57
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• 2005

Along with the development of the industrial society, as the transportation of water which is the indirect capital of society and petroleum, gas, etc used as energy sources is rapidly increased. the underground material is being expanded. Like this, the pipes laid under the ground not only bring the corrosion to the land circumstances to reduce the life of the pipes, but also raise the social problem of leakage accidents and the economic loss by Pin Hole. By reason of this, for the purpose of protecting the corrosion of the underground material, we are constructing and operating the electrolytic protection facilities. In case of a region of which specific resistance is high, however, we are not keeping proper protection potential(that is -850mV) to get protection effects. In this study, for the water pipes that under-voltage phenomena occur in the protection potential, we made a spot survey on the under-voltage section and normal-voltage section, compared, analyzed each of the contents and examined the under-voltage causes of the protection potential.

• 대한화장품학회지
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• 제27권1호
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• pp.119-131
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• 2001

Exposure of the human skin to UV-light can cause sun-tanning, photoaging and even photo-carcinogenesis. Melanin is important in protecting the skin against UV damage, but excessive or uneven melanin production can lead to the formation of freckles and aged spot. Control of hyperpigmentation is becoming even more important as aged population continues to grow. These needs led us to develop effective and safe depigmenting-agent, kojyl 3-aminopropyl phosphate (kojyl-APPA), called Whitegen. The development of whitegen was based on the fact that phosphate group of 3-aminopropyl phosphate can make kojic acid more compatible to the skin membrane and more stable. Instability of kojic acid has been a problem in cosmetic use. The insertion of phosphoester group has been recognized as a powerful tool to improve such physical properties as solubility and stability, because the phosphodiester residue is well characterized as a non-toxic moiety, having a high affinity for cell membranes. Kojyl-APPA showed no tyrosinase inhibition effect compared to kojic acid in vitro, but showed tyrosinase inhibition effect in situ. It means that kojyl-APPA is converted to kojic acid enzymatically in cells. Kojyl-APPA showed the inhibitory activity on melanin synthesis in mouse melanoma and normal humal melnaocytes and also showed long-lasting stability in comparison with its original form (kojic acid). Kojyl-APPA showed depigmenting effects when applied to UVB-induced hyperpigmentated region of guinea pig skin. Based on these results, kojyl 3-aminopropyl phosphate can be used as a safe and effective ingredient for the brightness and cleanness of skin.

• Radiation Oncology Journal
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• 제22권3호
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• pp.165-176
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• 2004

목적: 두개척수조사(Craniospinal irradiation) 후 전두엽 하방에서 재발(Subfrontal recurrence) 한 수모세포종 두 예를 경험하고, 방사선치료 측면에서 재발의 원인을 분석하고자 하였으며, 효과적인 구제 치료 방법을 모색 하고자 하였다. 대상 및 방법: 두 예 모두 고위험군(T3bMl, T3bM3) 수모세포종으로 수술, 항암화학제 및 방사선 병합요법을 시행 받았으며, CT-Simulation으로 방사선치료계획이 이루어졌다. 한 예는 방사선치료 후 16개월에 재발하여 구제수술을 시행하고, 세기조절방사선치료로 30.6 Gy의 방사선을 재조사하였다 다른 한 예는 12개월에 재발하여 구제수술만 시행하였다. 재발인자 확인을 위해 초기 방사선치료 시 사용되었던 모의치료사진을 확인하였고, 안구차폐의 과다 여부 및 가능한 원인 인자의 분석과 재발을 방지하기 위한 대안을 찾고자 하였다. 한 예에서 방사선재조사에 대한 부담과 주변 중요정상장기의 인접성 때문에 전두엽하방재발 종양에 대한 구제 치료로서 세기조절방사선치료를 계획하였으며, 표적체적에 대해서 7문 조사, 평균선량 30.6 Gy (1.8 Gy 분할, 최대선량의 85$\%$)를 처방하고, 주변 정상중요장기인 시신경은 평균선량을 25 Gy, 안구는 10 Gy로 제한하였다. 결과: 두 예 모두에서 모의치료사진상 정상장기 보호를 위한 안구차폐과다로 인한 전두엽하방 표적체적 일부에서의 저선량점을 확인할 수 있었다. CT-Simulation 상에서 automatic organ drawing 기능을 이용하여 전뇌와 안구의 외측 경계를 모의치료사진 화면에 같이 올릴 경우 차폐의 적절성을 판단하기가 더 용이하였다. 세기조절방사선치료계획 결과 표적체적에는 평균선량 31.1 Gy, 최대선량 36 Gy, 좌측 및 우측 시신경의 평균선량은 각각 13.9 Gy와 14.7 Gy, 좌우측 안구의 평균선량은 각각 5.5 Gy와 6.9 Gy로 우수한 치료계획을 획득하였다. 구제치료로 수술 및 세기변조방사선치료를 시행한 환자는 이후 방사선치료에 의한 부작용 없이 1년간 무병상태이다. 결론: 수모세포종의 전두엽하방 재발을 방지하기 위한 노력으로 두개척수조사 시 전두엽하방 및 체판 부위에 대한 각별한 주의를 기울여 차폐를 실시하여야 하겠고, 일단 재발하여 방사선재조사의 필요가 있는 경우 주변정상장기와의 방사선 선량 차이를 극대화할 수 있는 세기조절방사선치료를 통해 방사선치료 부작용의 부담을 줄일 수 있을 것으로 기대된다

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권5호
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• pp.373-384
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• 2001

Cellular proliferation is an intricately regulated process mediated by the coordinated interactions of critical growth control genes. Two of these factors in mammalian cells are the p53 and mdm-2 genes. A protein product of the mem-2 oncogene has been recently shown to associate with the protein encoded by the tumor suppressor gene p53. The p53 tumor suppressor protein is stabilized in response to DNA damage and other stress signals and causes the cell to undergo growth arrest or apoptosis, thus preventing the establishment of mutations in future cellular generations. Mutation or loss of p53 is a very common event in tumor progression. It occurs in about 50% of all tumors analysed including of colon, lung, breast and liver. The cellular mdm-2 gene, which has potential transforming activity that can be activated by overexpression, is amplified in a significant percentage of human sarcoma and in other mammalian tumors. Proteins encoded by the mdm-2 gene are able to bind to the p53 protein and, when overexpressed, can inhibit p53's transcriptional activation function, thus mdm-2 can act as a negative regulator of p53 function. Experimental study was performed to observe the relationship between p53 gene mutation and mdm-2 protein expression and apply the results to the clinical activity. 36 golden syrian hamster each weighing $60{\sim}80g$ were used and painted with 0.5% DMBA by 3 times weekly on the right buccal cheek(experimental side) for 6, 8, 10, 12, 14 and 16 weeks. Left buccal cheek(control side) was treated with mineral oil as the same manner to the right side. The hamsters were sacrificed on the 6, 8, 10, 12, 14 & 16 weeks. Normal and tumor tissues from paraffin block were examined for histology and immunohistochemistry observation, and were completely dissected by microdissection and DNA from both tissue were isolated by proteins K/phenol/chloroform extraction. Segments of the hamster p53 exons 5, 6, 7 and 8 were amplified by PCR using the oligonucleotide primers, and then confirmational change was observed by SSCP respectively. The results were as follows : 1. Dysplasia at 6 weeks, carcinoma in situ at 8 weeks and invasive carcinoma from 10 weeks could be observed in experimental groups. 2. p53 mutations were detected in 10 of the 36(28%) and the exons 6(6 of the 10 : 60%) was the most hot spot area among the highy conserved region(exons 5, 6, 7 & 8). 3. Immunohistochemical study confirmed 22 of the 36(61%) of p53 expression involving 10 of p53 mutations. 4. mdm-2 expression of was showed in 3 of the 36(8%) involving 1 of the 22 of p53 expression and 2 of the 14 of p53 non-expression. From the above results, mutation of p53 gene or expression of p53 protein may have the influence of the DMBA induced carcinoma of hamster buccal pouch but the expression of mdm-2 protein may not have relationship with tumorigenesis.