• Elastomers and Composites
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• 제48권1호
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• pp.10-17
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• 2013

선형 poly(ethylene-ter-1-hexene-ter-divinylbenzene) 소프트 탄성체 블럭내의 styrene 관능기로부터 poly(t-butylstyrene)하드 블록을 graft-from 음이온 중합을 통해 고온에서 사용 가능한 기능성 폴레올레핀 열가소성 탄성체인 polyolefin-g-poly(t-butylstyrene)을 합성하였다. sec-BuLi/TMEDA와 styrene 단위로부터 반응에 의하여 100% 수율의 음이온 개시 자리를 만들고 4-tert-butylstyrene을 graft-from 중합시켜 10,000~30,000 g/mol 분자량을 가지는 블록을 합성함으로서, 고온 $T_g$를 가지는 폴리올레핀 그라프트 고분자를 얻을 수 있었다. 단량체 함량과 중합시간에 따라 그라프트 분자량이 비례하여 증가하는 효과적인 리빙 중합방법임을 확인하였다. 사슬 말단에 다수의 수산기가 도입된 폴리올레핀 TPE의 합성방법으로서, 리빙 그라프트 고분자 사슬에 계속하여 isoprene을 블록 중합하여 얻어진 polyolefin-g-[poly(t-butylstyrene)-b-high vinyl polyisoprene]의 비닐기와 2-mercaptoethanol간의 thiol-ene 클릭 반응을 이용하는 방법을 통해 진행하였다. 연구 결과, 높은 $T_g$(> $145^{\circ}C$)를 갖는 정밀 제어된 기능성 그라프트 형태의 폴리올레핀 기반 TPE를 합성하는 방법을 확립하였다.

• Molecules and Cells
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• 제39권4호
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• pp.352-357
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• 2016

Vertebrate neurogenesis requires inhibition of endogenous bone morphogenetic protein (BMP) signals in the ectoderm. Blocking of BMPs in animal cap explants causes the formation of anterior neural tissues as a default fate. To identify genes involved in the anterior neural specification, we analyzed gene expression profiles using a Xenopus Affymetrix Gene Chip after BMP-4 inhibition in animal cap explants. We found that the xCyp26c gene, encoding a retinoic acid (RA) degradation enzyme, was upregulated following inhibition of BMP signaling in early neuroectodermal cells. Whole-mount in situ hybridization analysis showed that xCyp26c expression started in the anterior region during the early neurula stage. Overexpression of xCyp26c weakly induced neural genes in animal cap explants. xCyp26c abolished the expression of all trans-/cis-RA-induced posterior genes, but not basic FGF-induced posterior genes. Depletion of xCyp26c by morpholino-oligonucleotides suppressed the normal formation of the axis and head, indicating that xCyp26c plays a critical role in the specification of anterior neural tissue in whole embryos. In animal cap explants, however, xCyp26c morpholinos did not alter anterior-to-posterior neural tissue formation. Together, these results suggest that xCyp26c plays a specific role in anterior-posterior (A-P) neural patterning of Xenopus embryos.

• 미생물학회지
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• 제50권4호
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• pp.384-386
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• 2014

녹농균은 병원, 물, 토양 및 대기 등의 많은 자연과 인공환경에서 서식하는 기회주의적 병원체로, 병원 내 감염 등의 심각한 문제점을 야기할 수 있다. 본 연구에서는 신뢰높은 표준화 방법인 International Organization for Standardization (ISO)을 적용하여, 물과 토양에서 220개의 녹농균의 추정 집락을 분리하였으며, 생리생화학적 특성으로 녹농균을 동정하였다. ISO/NP 16266 방법을 적용하였을 때, 총 220개의 추정 집락 중 방류수에서 drain swab으로 채취한 오직 1개의 집락만이 최종적으로 녹농균 양성으로 확정되었다. 한편, ISO에서 2014년 새롭게 제안한 1,10 phenanthroline 저항성 실험은, 환경 중 P. aeruginosa를 검출 및 동정하기 위해 적합한 방법으로 사료된다.

• 대한임상독성학회지
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• 제16권2호
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• pp.75-85
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• 2018

Purpose: This study examined the Poisoning Severity Score (PSS) from acute poisoning patients, to determine the relationships among the PSS, PSSsum, the primary outcome (prolonged stay at the ER over 24 hours, general ward and ICU admission and the application of intubation and mechanical ventilator, and the administration of inotropes). Methods: A retrospective study was conducted through the EMR for 15 months. The PSS grade was classified according to the evidence of symptoms and signs. The differences in the primary outcomes between the PSS of when a single organ was damaged, and the PSS, PSSsum combined with the grade of when multiple organs were damaged, were studied. The cutoff value was calculated using the receiving operating characteristics (ROC) curve. Results: Of the 284 patients; 85 (29.9%) were men with a mean age of 48.8 years, and their average arrival time to the ER was $4.4{\pm}6.7\;hours$. The most frequently used drug was hypnotics. The number of patients with PSS grade 0, 1, 2, 3, and 4 was 17, 129, 122, 24, and one, respectively. No ICU admissions, application of intubation and mechanical ventilators, administration of inotropes were observed among the patients with PSS grades 0 and 1 but only on patients with PSS grades 2 to 4. At PSS, when separating the patients according to the number of damaged organs, 17 had no symptoms, 133 had one organ damaged, 75 had two organs damaged, 36 had three organs damaged, and 23 had four organs damaged. Significant differences were observed between increasing number of damaged organs and the primary outcome. Conclusion: Among the acute poisoning patients, the PSS was higher in severity when the grade was higher. The number of damaged organs and the primary outcome showed meaningful statistical differences. This study confirmed that when the patients' PSS>2 and PSSsum>5, the frequency of ICU admission was higher, and they were considered to be severe with an increased prescription risk of application of intubation and mechanical ventilator, and the administration of inotropes.

• 대한지역사회작업치료학회지
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• 제3권2호
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• pp.33-46
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• 2013

목적 : 가상현실 프로그램과 현실화된 과제 지향 프로그램이 노인의 균형에 어떠한 영향을 미치는지 그 효과를 비교해 보고자 한다. 연구방법 : 12명의 건강한 노인을 대상으로 가상현실 프로그램과 현실화된 과제 지향 프로그램을 각각 6주간 주 2회씩 실시하였다. 균형 능력 변화를 위해 버그 균형 척도(Berg Balance Scale: BBS), 이동 능력검사(Timed Up and Go: TUG), 한 발 서기 검사(One-Legged Stance Test: OLST), 5회 반복 앉았다 일어서기 검사(5-Repetition Sit-To-Stand Test: 5R-STS Test)를 사용하였다. 결과 : 분석결과 프로그램 전 후에서는 통계적으로 유의한 결과를 얻지 못하였다. 하지만 세 집단 간 비교에서는 버그 균형 척도, 한 발 서기 검사 중 눈 뜨고 좌, 우에서 통계적으로 유의한 결과를 얻었으며 사후 검정결과 눈 뜨고 검사 - 좌에서 가상현실 프로그램과 현실화된 과제 지향 프로그램 간에 유의한 결과를 얻었다. 결론 : 현실화된 과제 지향 프로그램은 노인의 균형 능력 향상에 좀 더 긍정적이었으며 임상 및 지역사회에서 좀 더 쉽게 수행할 수 있는 프로그램으로 유용하게 사용될 수 있을 것이라 생각된다.

• 한국농공학회논문집
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• 제58권5호
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• pp.11-18
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• 2016

The objective of this study was to develop the simple method to estimate ungauged river section for flood stage analysis. Damage prediction should be prioritized using hydrological modeling to reduce flood risk. Mostly, the geographical data using hydrological modeling depends on national river cross-section survey. However because of the lack of measured data, it is difficult to apply to many local streams or small watersheds. For this reason, this study suggest the method to estimate unguaged river cross-section. Simple regression equations were derived and used to estimate river cross-section by analyzing the correlation between the river cross-sectional characteristics (width, height and area). The estimated cross-sections were used to simulate flood level by HEC-RAS (Hydrologic Engineering Center's River Analysis System). The applicability of this method was verified by comparing simulated flood level between measured and estimated cross-section. The water surface elevation of the flood stage analysis was 6.56-7.24 m, 5.33-5.95 m and 6.12-6.75 m for measured cross section, for estimated cross section and for estimated cross section based on DEM elevation, respectively. Further study should consider other factors for more accurate flood stage analysis. This study might be used one of the guidelines to estimate ungauged river section for flood stage analysis.

• Journal of the Optical Society of Korea
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• 제19권6호
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• pp.700-704
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• 2015

As pH is a widely used index in chemical, medical, and environmental applications, research on pH sensors has been active in recent years. This study obtained RGB values by measuring the reflected light from a liquid sample to detect fine changes in pH, and performed mathematical modeling to investigate the relationship between the detected optical signal and pH value. Also, the trends in pH changes were easily identified by analyzing RGB values and displaying them in the color coordinate for easy visualization of data. This method implemented a user-friendly system that can measure and analyze in real time. This system can be used in many fields such as genetic engineering, environmental engineering, and clinical engineering, because it not only can measure pH but also replaces a colorimeter or turbidimeter.

• Perspectives in Nursing Science
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• 제10권2호
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• pp.120-132
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• 2013

Purpose: Since the perception of the public on nurses tends to be shaped substantially by the media, this study analyzed the image of nurses portrayed in Korean medical TV dramas. Methods: This study was on five Korean medical TV dramas in recent five years selected based on their popularity. Ten coders broke into five groups of two. Full episodes of each drama were assigned to each group. The coders made assessments separately and cross-matched their analysis, checking with the Holsti's method. Results: Ten of the analyzed twenty nurses were supporting characters. They were mainly in their twenties. Only one nurse was male and 13 (65%) were staff nurses. Nurses were described as strong (30.0%), active (30.8%) and kind (40.0%). They were mostly portrayed discussing patients mainly with doctors (24.4%). In terms of their attitude toward work, they appeared diligent (37.6%) and communicative (31.6%). Conclusion: There have been positive changes compared to past studies. Despite the enhancement in the image of nurses in medical dramas, there is yet a long way for dramas to properly portray the professionalism nurses truly have. Further research is needed and diverse measures should be taken for the improvement in the social recognition of the nursing profession.

• 한방재활의학과학회지
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• 제31권2호
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• pp.1-14
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• 2021

Objectives We evaluated the improving effects of Taeksa-tang (TST) using 3T3-L1 cells and C57BL/6 mice were fed on a high-fat diet. Methods The anti-radical activities of TST were studied using 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid). The content of total polyphenol was measured using Folin-Ciocalteu reagent, whereas aluminum chloride colorimetric method was used for the content of total flavonoid. Moreover, the factors related to lipid profile and the protein expressions such as 𝛽-oxidation and anti-oxidant enzyme were analyzed using serum and western blotting of 3T3-L1 cells. Additionally, we examined lipolysis through glycerol appearance in mouse adipose tissue. Results TST treatment showed strong free radical scavenging activities with half maximal inhibitory concentration and the presence of a amount of total polyphenol and total flavonoid. TST treatment significantly increased factors related to 𝛽-oxidation such as carnitine palmitoyl transferase-1 and uncoupling protein 2 via the phosphorlyation of liver kinase B1 (LKB1) and AMP-activated protein kinase (AMPK). Moreover, the protein expressions of anti-oxidant enzyme and lipolysis were significantly elevated by TST administration. In addition, TST supplementation lowered serum malondialdehyde, triglyceride, and total cholesterol levels compared with the control group. Taken together, these data suggest that TST treatment regulated lipid parameters via the increase of 𝛽-oxidation by LKB1-AMPK signaling pathway. Conclusions TST may have a potential remedy in the prevention and treatment of obesity. Therefore, this study may provide the scientific basis for TST use.

• 대한화장품학회지
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• 제47권1호
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• pp.75-84
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• 2021

본 연구에서는 3 개의 아미노산으로 이루어진 트리펩타이드의 미세먼지에 의한 인간각질형성세포의 손상 억제 효과에 대해 확인하였다. 실험 결과 트리펩타이드 처리 시 미세먼지에 의한 세포 사멸이 억제되어 생존율 증가가 관찰되었으며, aryl hydrocarbon receptor (AhR) 기전 활성이 억제 되어 독성 대사체 생성과 염증반응에 관여하는 하위 인자인 cytochrome P450 family 1 subfamily A member 1 (CYP1A1) 및 cyclooxygenase-2 (COX-2)의 발현이 저해되었다. 또한 미세먼지에 의한 산화적 스트레스 억제 효과를 나타내어 염증성 사이토카인의 발현을 저해하였고, 피부 구성 단백질의 분해를 유도하는 matrix metalloproteinase-1 (MMP-1)의 발현을 저해하였으며, 세포 사멸 인자의 수준을 저해하였다. 이 결과를 종합해 볼 때, 본 연구의 트리펩타이드는 미세먼지에 의한 인간각질형성세포의 사멸 및 주변 피부 조직의 손상을 유도할 수 있는 기전들을 억제하여 보호 효과를 나타내는 것으로 보인다. 트리펩타이드의 이러한 안티폴루션 효과는 신규 기능성 화장품 소재로 응용될 수 있을 것으로 기대된다.