• 한국방사선학회논문지
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• 제14권3호
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• pp.303-311
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• 2020

일반영상 검사 시 발생되는 산란선은 검사목적 부위 외 다른 장기 및 조직에 대해 2차적인 피폭을 유발할 수 있다. 현재 방사선 피폭을 저감하기 위해 사용되는 차폐기구는 종사자들의 방사선 방호 목적으로 대부분 사용되며, 환자의 방사선 방호는 거의 이뤄지지 않고 있다. 이에 본 연구에서는 모의실험을 통해 일반 영상 검사 시 산란선에 의한 장기 선량과 3D 프린팅 재료를 통한 방사선 차폐기구로의 효용성을 평가하고자 한다. 그 결과, 검사 시 장기별 흡수선량은 선원과의 거리가 인접하고, 피부표면에 근접한 장기일수록 2차 산란선에 의해 높은 영향을 나타내었다. 이를 방호하기 위한 3D 프린팅 차폐기구 사용에 따른 선량감소효과는 플라스틱 계열에 비해 혼합 프린팅 재료의 경우 더 높은 차폐효과를 나타내었다.

• 한국식품영양학회지
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• 제22권1호
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• pp.103-109
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• 2009

현재까지 미생물에 의해 생산되는 10,000여 종의 항생물질 가운데 약 2/3 에 해당하는 64% 정도가 방선균으로부터 발견되었다. 따라서 토양 중에 널리 분포하고 있는 방선균을 분리하여 광범위 항생물질 생산능이 가강 우수한 Y-88을 최종 선정하였다. 이 균을 형태학적, 생리상 및 배양학적으로 동정한 결과 Streptomyces 속으로 밝혀져 Streptomyces sp. Y-88 이라 명명하였다. Y-88로부터 항생물질 생산 최적 배양조건을 검토한 결과 soluble starch 1.6%, glucose 1.6%, beef extract 0.6%, $K_2HPO_4$, $MgSO_4$ $7H_2O$ 및 $ZnSO_4$ $7H_2O$가 각각 0.01%였으며, 최적 pH4.0, 배양온도 25$^{\circ}C$ 그리고 배양시간으로 위의 조건에 30시간에서 항생물질 생산이 빠른 것으로 나타났다.

• 한국축산식품학회지
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• 제35권3호
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• pp.413-420
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• 2015

The aim of our study was to evaluate the potential benefits of an oral supplement containing porcine placenta extract (PPE) on skin parameters related to cutaneous physiology and aging. PPEs were administered orally to hairless mice for 12 wk. The effects of oral PPE administration on skin water-holding capacity and Transepidermal Water Loss (TEWL) were similar to those of oral collagen (HYCPU2) administered as a positive control. Magnified photographs and replica images showed a reduction in UVB-induced wrinkle formation after collagen and PPE treatments. PPE treatments ameliorated the thicker skin surface that results from UVB exposure, based on a histological examination of skin tissue. The groups that were orally administered PPE (0.05%, OL; 0.1%, OH group) showed significantly reduced Matrix Metaloproteinase-2 (MMP-2) mRNA expression levels compared with the UVB control (Con), by 33.5% and 35.2%, respectively. The mRNA expression of another collagen-degrading protein, MMP-9, was also significantly lower in the groups that received oral administration of PPE (especially in the OH group) than in the control group. Additionally, oral administration of PPE significantly upregulated tissue inhibitor of metalloproteinase-1 (TIMP-1) and -2 mRNA expression levels compared with expression levels in the control group (p<0.05). This indicates that orally administered PPE activated the expression of Timp-1 and -2, inhibitors of MMP, which is responsible for collagen degradation in skin. Taken together, we propose that long-term oral administration of PPE might have a beneficial effect with respect to skin photo-aging.

• 한국화재소방학회논문지
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• 제22권2호
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• pp.30-37
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• 2008

건축용 바닥재의 화재예방을 위하여 국제규격으로 정해져 있는 바닥재 시험평가 방법인 KSISO 9239-1을 이용하여 각종 바닥재에 대한 연소성 시험을 복사열 판넬 시험기를 사용하여 실시하였다. 복사열 판넬 시험기를 이용하여 각종 바닥재에 대한 화염 전파거리, 임계 열류량 그리고 연기 발생농도 측정하였다. 측정결과 바닥재의 구성 물질 별로 서로 다른 연소특성을 나타내었으며, 바닥재의 표면 재질 및 구성성분이 열 방출과 연기 발생량에 있어 중요한 영향을 미치게 된다는 것을 확인할 수 있었다. 위의 평가방법은 화재위험성을 연구하는데 중요한 인자인 임계 열류량, 연기 발생량 및 화염 전파거리를 정량적으로 평가하는 중요한 시험방법임을 알 수 있었고 국내 건축용 바닥재 화재평가 방법을 국내실정에 맞게 제정 및 적용하는 것이 적합할 것으로 판단되었다.

• 한국의류학회지
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• 제34권12호
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• pp.2073-2084
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• 2010

This study provides references that can be applied to future suit design by analyzing the formative characteristics of modern men's and women's suits. Research on related literature and case studies were carried out simultaneously. A criterion for analyzing formative characteristics of suits was drawn up through an examination of past research. A total of 1,410 suit photographs that appeared in the U.S. edition of Vogue Magazine from 1985 to 2008 were analyzed in order to observe the formative characteristics of men's and women's suits. Research results showed that in the 1980s suits pursued a more comfortable and natural fit based on the original properties of simplicity, modernity, and practicality; in addition, women's suits had a tendency to use excessive shoulder pads due to the power-look influence. In the early 1990s exaggerated shoulders and boxy straight silhouettes were in fashion but towards the later years suit designs gradually started to fit the body and established a skinny versus slouch conflict. Women's suits gradually began to show more curvy body lines, and men's suits became more feminine on the surface in terms of color and material. In the 2000s suits have become more feminine and sensual than the 1990s, design focuses of both men's and women's suits moved to the waistline. Skinny and long styles became the ideal silhouette and differences between formative characteristics of the two genders decreased. Fashion elements of men's and women's suits are seen to have changed with a mutual intimate connection under the influence of a similar societal environment.

• 생약학회지
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• 제47권2호
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• pp.128-136
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• 2016

Tiny leaf fragments were found in the Annals of the Joseon Dynasty, which were compiled about 500 years ago. The records describing the detailed process of compiling the Annals indicate that silk bags packed with the powders of 'Cheongung' and 'Changpo', which have been used as traditional herbal medicines in the northeast Asian countries such as China and Japan as well as Korea, were put in the wooden storage boxes together with the volumes of the Annals. However, there is no record that parts of plants were used in the process of compiling the Annals. The botanical origin of leaf fragments was identified as Ligusticum sinense 'Chuanxiong' by the analysis of trnK of chloroplast DNA as well as the examination of leaf surface with SEM. The comparative analysis of trnK sequences showed that the chloroplast DNA haplotype of 'Tocheongung', a triploid species cultivated in Korea, was identical with Cnidium officinale, but different from L. sinense 'Chuanxiong'. The molecular results provide a new suggestion on the botanical origin of crude drugs used as 'Cheongung', which has been disputed in Korea.

• The Plant Pathology Journal
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• 제23권3호
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• pp.223-225
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• 2007

Many plant growth-promoting rhizobacteria (PGPRs) have been known for beneficial effects on plants including biological control of soilborne pathogens, induced systemic resistance to plant pathogens, phytohormone production, and improvement of nutrient and water uptake of plants. We developed a simple and rapid method for screening potential PGPR, especially phytohormone producing rhizobacteria, or for analyzing their functions in plant growth using cucumber seedling cuttings. Surface-sterilized cucumber seeds were grown in a plastic pot containing steamed vermiculite. After 7 days of cultivation, the upper part 2 cm in length of cucumber seedling, was cut and used as cucumber cuttings. The base of cutting stem was then dipped in a microcentrifuge tube containing 1.5ml of a bacterial suspension and incubated at $25^{\circ}C$ with a fluorescent light for 10 days. Number and length of developed adventitious roots from cucumber cuttings were examined. The seedling cuttings showed various responses to the isolates tested. Some isolates resulted in withering at the day of examination or in reduced number of roots developed. Several isolates stimulated initial development of adventitious roots showing more adventitious root hair number than that of untreated cuttings, while some isolate had more adventitious root hair number and longer adventitious roots than that of untreated control. Similar results were obtained from the trial with rose cuttings. Our results suggest that this bioassay method may provide a useful way for differentiating PGPR's functions involved in the development of root system.

• Parasites, Hosts and Diseases
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• 제35권2호
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• pp.111-118
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• 1997

Theileria sergeni의 진단방법으로 Giemsa 염색에 의한 광학현미경적 관찰이 가장 통상 적으로 이용되고 있으나 감염이 아주 적거나 내과성인 경우 검출하기가 매우 곤란하다. 이에 PCR 진단을 위한 대강유전자로서 p33의 염기서열을 이용하여 4개의 oligonucleotide primers. TS1, TS2 ,TS3,, TS4를 작성하였다. 작성된 primer의 각 조합에 따라 PCR한 결과 TS1과 TS4 조합에서는 499 bps, TS1과 TS3 조합에서는 381 bps, TS2와 TS4 조합에서는 365 bps, TS2 와 TS3 조합에서는 247 bps 크기의 산물을 획득하였다 이 PCR산물은 p33 유전자 염기서열 분석을 통한 제한효소처리 및 Southern blot hybridization 방법을 통하여 그 특이성을 확인하였다. Primer의 특이성을 조사한 결과 미감염 백혈구 및 다른 주혈기생충인 Babesic ouota, Anaplosmn marginate에 대해서는 교차 반응을 나타내지 않았다. 또한 야외시료에 PCR 기법을 적용한 결과 Giemsa 염색에 의한 광학현미경적 관찰에서는 64.8%의 양성률을 보인 반면, PCR 진단에서는 본 실험에서 작성된 TS1과 TS4, TS2와 TS3 조합이 공희 88.7%의 양성률을 나타내었다.

• 대한수의학회지
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• 제42권2호
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• pp.153-162
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• 2002

For the induction of arthropathy, 5% hydrogen peroxide($H_2O_2$) was injected for 5 weeks into the intraarticular space of the New Zealand white rabbits to damage articular cartilage. Alginic acid of low molecular weight (2%) made from macromolecular alginate treated with enzyme was administered into articular space at the dose of 5 mg/kg twice a week for 3 and 6 weeks using 1 ml syringe and 26 G needle. Saline was injected for the control. Tissues surrounding the articulation were obtained for the measurements of superoxide dismutase(SOD) activity as a major antioxidant enzyme and malondialdehyde (MDA) as a lipid peroxidation level. Histopathologic examination on the surface of articular cartilage was carried out. Data showed that injection of hydrogen peroxide for 5 weeks had led to the induction of free radical damage and of articular cartilage change as confirmed by microscopic observation. The application of hydrogen peroxide caused a gradual increase in the SODs and MDA. These patterns were similar after 3 and 6 weeks of alginate treatment. Furthermore, microscopic examinations revealed that hydrogen peroxide caused flaking, fibrillation, fissuring, denudation, and hypocellularity in the articular surfaces. In conclusion, lipid peroxidation was demonstrated in the articular cartilage by the administration of hydrogen peroxide in the rabbit model. This lipid peroxidation could be caused by oxygen free radicals. The histologic and enzymatic correlations on lipid peroxidation in the articulation have provided a better understanding of arthropathy. It is possible to take advantage of these findings to evaluate effective alginate dosage more efficiently.

• 한국해양공학회지
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• 제11권4호
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• pp.61-75
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• 1997

The social demand urges us to use some equipments and structures in high temperature environment. By this occasion, the necessity of studying the fatigue crack growth is an important aspect of new materials. However, the present situation is rarely to accumulate the fatigue data. Especially, 1Cr-1Mo-0.25V steel and 304 stainless steel have been increased to be used under the severe condition of high temperature. And so, the fatigue estimation of those materials is important and appropriate. Fatigue tests have been carried out to examine the crack initiation, growth behaviour for the small fatigue crack of 1Cr-1Mo-0.25V steel and 304 stainless steel at room temperature and 538^{\circ}C$. The remote measurement system which has many merits of checking and saving the image for detailed examination was applied to closely detect the crack length. Generally, the fatigue crack initiated in the form of multiple cracks and grew each other. And then it coalesced to become a major crack. The major crack governed the rest of the fatigue life. In the growing process, each peripheral cracks interact and grow for a certain period. After then, it coalesced and fractured. On the basis of the above experimental data for the small crack, a simulation program was developed to predict the residual life time and to estimate the integrity of machine elements and structures. At the same time, the simulation was extended to 1Cr-1Mo-0.25V steel. The simulation results have shown a good agreement to those of the experimental ones for both materials of 1Cr-1Mo-0.25V steel and 304 stainless steel with small cracks. The NASCRAC has applied to compare the fatigue life with the experimental results. And so, it can be said that the simulation program is valuable tools to the industrial fields.