• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.397.1-397.1
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• 2014

최근 방사선 진단 영역에 이용되고 있는 증감지는 입사된 방사선의 감도를 증가시키기 위해 형광체를 사용하고 있으며, 외부의 에너지를 흡수하여 빛으로 방출하는 역할을 한다. 이는 방사선 검출기, 디스플레이, 의료기기 등 다양한 분야에 활용되고 있다. 필름에 X선을 노출 할 경우 형광체의 사용 유무에 따라 방사선 흡수 효율에 영향을 미치며, 이는 발광 효율 및 감도에 주요한 인자로 작용한다. 현재 상용화되어 있는 형광체는 낮은 발광 효율로 인한 한계를 가지므로, 발광 효율 향상을 위하여 제작 구조에 대한 연구가 진행되고 있다. 이 중 반사막을 활용하는 연구가 활발히 진행되고 있다. 일반적으로 형광체의 제조를 위하여 보편적으로 이용하고 있는 스크린프린팅 방법에서 건조 공정을 수행 시 균일도가 감소하는 현상이 발생한다. 이러한 현상은 반사막의 증착을 불균일하게 만드는 원인으로 작용하고 빛의 산란을 초래하는 현상을 초래한다. 이에 본 연구에서는 증착 시 투명도 저하에 따라 반사율이 증가되는 반사막 성질을 가지며, 방수성 및 절연성과 같은 보호층 특성을 지닌 유기성 투명 박막 페를린에 대하여 연구하고자 한다. 본 연구에서는 화학적 증기 증착법(Chemical Vapor Deposition, CVD)을 이용하여 투명 필름의 상단에 페를린을 코팅한 시편과 코팅하지 않은 시편으로 구분하여 제작하였고, 상단에 스크핀프린팅 방법을 활용하여 형광체를 도포 하였다. 시편 제작 후 실험은 시편을 필름 상단에 위치시키고, 일반진단에너지 대역(Model-SF 80)의 X선을 조사하였다. 이 후 현상기(model-pro14)를 통해 현상된 필름에 나타난 광학적 농도(Optical Density, O.D)를 농도계(Fluke Biomedical Nuclear Associates Densitometer)로 측정하였는데, 불확실성을 줄이기 위하여 총 5회를 측정하여 그 중 2번째로 높은 값을 도출하였다. 측정 결과, 페를린을 코팅한 형광체에서는 1.71의 O.D 값이 측정되었고, 페를린을 코팅하지 않은 형광체에서는 1.43의 O.D 값이 측정되었다. 이를 이용하여 투명도를 산출한 결과 상대적으로 약 1.76% 차이가 나타났다. 이러한 결과는 페를린 활용 시 환자의 피폭 선량 저감화 및 해상력 개선을 도모할 수 있을 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1785-1790
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• 2013

The synthetic machinery of ATF4 (activating transcription factor 4) is activated in response to various stress conditions involved in nutrient restriction, endoplasmic reticulum homeostasis, and oxidation. Stress-induced inhibition of proteasome activity triggers the unfolded protein response and endoplasmic reticulum stress, where ATF4 is crucial for consequent biological events. In the current study, we showed that the $NAD^+$-dependent deacetylase, SIRT1, suppresses ATF4 synthesis during proteasome inhibition. SIRT1 depletion via transfection of specific siRNA into HeLa cells resulted in a significant increase in ATF4 protein, which was observed specifically in the presence of the proteasome inhibitor MG132. Consistent with SIRT1 depletion data, transient transfection of cells with SIRT1-overexpressing plasmid induced a decrease in the ATF4 protein level in the presence of MG132. Interestingly, however, ATF4 mRNA was not affected by SIRT1, even in the presence of MG132, indicating that SIRT1-induced suppression of ATF4 synthesis occurs under post-transcriptional control. Accordingly, we propose that SIRT1 serves as a negative regulator of ATF4 protein synthesis at the post-transcriptional level, which is observed during stress conditions, such as proteasome inhibition.

• 보존과학회지
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• 제36권4호
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• pp.255-263
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• 2020

Paulownia coreana has various advantages as a convenient workability, aesthetic outlook, beautiful patterns, low weight and high strength, and its permeability. P. coreana has been widely used for storage but there are no empirical researches proving its functionality in a field of conservation science until now. In this study, the seasonal and daily temperature and relative humidity control, and microbe and insect repellent activity were evaluated under the controlled and uncontrolled circumstances from 2015 to 2016. The results showed to be mainly excellent in relative humidity control and the buffering effect was good to adjust the average daily relative humidity range from the outside. With respect to the antimicrobial properties of P. coreana, we observed that its water-soluble extract produced visible zones of inhibition against five bacteria. However, it was difficult to predict the antimicrobial and/or insecticidal properties.

• 한국물환경학회지
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• 제20권6호
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• pp.547-554
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• 2004

We found that the Bacterium Burkholderia cepacia in livestock wastewater treatment plant was predominant species. We investigated the growth rate of this and treatment characteristics for organic matter and nitrogen removal in livestock wastewater using this microorganism. First, we cultured B. cepacia. And then, to conducted treatment for livestock wastewater by using B. cepacia., we changed C/N from 0.2~4.4. When we operated A and B process, changing F/M ratio from 1.2 to 4.4. In experiment of C/N variations, when C/N was 1.8, we found that the optimal condition for organic matter and nutrient removal effect was higher and the removal efficiency of $SCOD_{cr}$, $SBOD_5$,$NH_4-N$ was 78.4%, 95% and 74.8%. So, It is possible to treat the wastewater having the lower C/N contents such as livestock wastewater using this microorganism. In experiment of A and B process for livestock wastewater, we found that the removal efficiency of organic matter and nitrogen in operating mode of A process was higher than that of B process. Also, the optimal F/M operating A process was 0.013 and the removal efficiency of $SBOD_5$, $SCOD_{cr}$, TN and TP were 97%, 60%, 95% and 91%.

• 동의생리병리학회지
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• 제19권3호
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• pp.785-791
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• 2005

Corydalis Tuber has traditionally been used for the treatment of water retention in the body. Administration of the aqueous extract of Corydalis Tuber has been known to be effective for the control of pain and treatment of arthritis. It was reported that Corydalis Tuber possesses anti-inflammatory activity and modulates the intestinal immune system. The effect of Corydalis Tuber against LPS-stimulated expressions of COX-2, iNOS, and $IL-1{\beta}$ in cells of the murine RAW 264.7 macrophages was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, reverse transcription-polymerase chain reaction (RT-PCR), $PGE_2$ immunoassay, and NO detection. The aqueous extract of Corydalis Tuber was shown to suppress $PGE_2$ production by inhibition on the LPS-stimulated enhancement of COX-2 enzyme activity, $IL-1{\beta}$, and iNOS expression in the RAW 264.7 macrophages. Present results suggest that Corydalis Tuber exerts anti-inflammatory and analgesic effects probably by suppressing of COX-2, iNOS, and $IL-1{\beta}$ expressions, resulting in inhibition of $PGE_2$ synthesis. Corydalis Tuber has anti-inflammatory and analgesic effects probably by suppressing of COX-2, iNOS, and $IL-1{\beta}$ mRNA expressions, resulting in inhibition of $PGE_2$ and NO synthesis.

• 펄프종이기술
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• 제47권2호
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• pp.1-8
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• 2015

Disposable diaper has been used in order to handle urine and feces conveniently. At present the amount of disposable diaper waste increases gradually. Incineration and landfill have been the only ways to dispose of disposable diapers. However, if they are disposed by landfill, decomposition will take more than one hundred years. In addition, another way of dispose incineration has caused air pollution. Therefore, it is necessary to study recycling process for disposable diaper since plastic and wood fibers of diaper are useful materials to recycle. In this study, pulping condition of disposable diaper waste was studied in order to effectively separate the components. Recovery rates of plastic and fibers were analyzed under different pulping conditions. It was found that optimum pulping consistency was 5%, time was 60 minutes, temperature was $50^{\circ}C$, and cut size is $21cm{\times}21cm$. The recovery rate of plastic and fibers can be achieved above 70% under the optimum pulping condition.

• 한국의류학회지
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• 제35권3호
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• pp.325-335
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• 2011

This study analyzes the current educational curricula in the field of Clothing and Textiles in order to develop appropriate educational methods and courses. We reviewed the curricula offered by 58 Clothing and Textiles Departments at four-year universities in Korea. We analyzed the educational content of each curriculum by dividing all of the courses offered into eight categories. The analysis was based on the information posted on the universities' Internet websites, and the analysis was performed by using descriptive statistics. The results of this study are as follows: First, the educational courses of the Clothing and Textiles Departments are composed of, 36.2% design, 20.4% production, and 14.5% textile categories. In comparison with the results of a similar study conducted in 1999, emphases on the design, distribution, and marketing categories have increased, while the emphases on the production, apparel material, basic knowledge, and consumption science categories have decreased. Second, in the case of the apparel material category, basic knowledge of materials constituted 18.5%, the largest part of the category. The average number of units offered in the area of apparel materials by the 58 Departments was 17 units per year. The curricula were found to vary by regions of the country. The universities located in the Chungcheong region offer more textile material courses, but the universities in the Capital region offer fewer textile material courses than other regions. Departments that are affiliated with universities that emphasize Art and Design have more courses on basic knowledge, dyeing and finishing, and fabric design than other universities.

• 한국식품과학회지
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• 제42권5호
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• pp.637-642
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• 2010

천연물 유래의 생약에서 조골세포 증식을 높이면서, 파골세포의 분화 억제에 효과가 있는 시료를 검색하고자 15종의 한약재추출물의 효과를 검토해 보았다. Mouse calvaria 유래의 osteoblastic cells를 이용하여 세포 생존률 및 ALP 활성을 측정하였으며, 또한 마우스 골수 세포를 이용하여 M-CSF와 RANKL을 처리하여 파골세포의 분화를 유도한 후, 세포 생존율과 TRAP효소활성을 측정하였다. 그 결과, 두충, 곽향, 개다래, 형개, 정공등 추출물은 조골세포 증식 및 ALP 활성를 증가시켰으며, 파골세포 활성을 나타내는 TRAP활성이 억제되는 것으로 확인되었다. 따라서 이 추출물들은 조골세포의 기능을 향상시키는 동시에 파골세포의 기능을 억제하여 골 흡수와 관련된 질환과 함께 골 질환 예방에 효과가 있을 것으로 생각되어진다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2018년도 춘계학술대회 논문집
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• pp.88-88
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• 2018

DLC(Diamond Like Carbon) 박막은 높은 열전도도, 큰 전기저항, 높은 강도 등의 다이아몬드와 유사한 특성을 가지고 있으면서 저온 저압에서도 합성이 가능하고, 합성 조건에 따라 물리 화학적 특성도 넓게 조절 할 수 있으며 상대적으로 넓은 면적에서 균일하고 평활한 박막의 합성이 가능하여 산업적 응용 면에서도 경쟁력을 갖추고 있다[1]. 이러한 DLC 박막을 합성함에 있어서 RF-PECVD(Radio Frequency Plasma Enhanced Chemical Vapor Deposition) 방법은 PECVD 방법 중 가장 보편적으로 사용되고 또 캐패시터 타입의 RF-PECVD 방법은 균일한 대면적 증착과 대량생산이 가능하다[1,2]. 본 연구에서는 우수한 특성을 갖는 DLC 박막의 증착 조건을 찾기 위해 캐패시터 타입의 RF-PECVD를 사용하여 공정 가스의 유량과 RF Power를 변화하여 박막을 증착하고, 증착된 박막의 특성을 연구하였다. DLC 박막은 ITO(Indium Tin Oxide) 유리 기판 위에 $100^{\circ}C$에서 5 min 동안 아세틸렌($C_2H_2$) 가스를 사용하여 가스 유량과 RF Power를 변화하여 증착하였다. 증착된 DLC 박막의 특성은 투과도, 평탄도, 두께를 측정하여 비교하였다. 가시광선 영역(380-780 nm)에서 투과도를 측정한 결과 ITO 유리 기판을 기준으로 한 DLC 박막의 투과도는 가시광선 영역 평균 94.8~98.8% 사이의 값으로 매우 높은 투과율을 나타내었다. 투과도는 가스 유량이 증가함에 따라 증가하는 경향을 나타내었고, RF Power의 변화에는 특정한 변화를 나타내지 않았다. 박막의 평탄도($R_a$, $R_{rms}$)와 두께는 AFM(Atomic Force Microscope)을 사용하여 측정하였다. 평탄도 $R_{rms}$는 0.8~3.3 nm, $R_a$는 0.6~2.5 nm 사이를 나타내었고 RF Power와 가스 유량의 변화에 따른 경향성을 나타내지는 않았다. 두께는 RF Power 25 W에서 55 W로 증가함에 따라 증가하는 경향을 나타내었으나 70W에서는 가스의 유량에 따라 상이한 결과를 나타내었다.

• 한국치위생학회지
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• 제16권1호
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• pp.11-18
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• 2016

Objectives: The purpose of the study was to compare the oral health related characteristics between a long-term patients and general population. Methods: A direct interview questionnaire was completed by 160 patients and 165 general people from January 16 to April 31, 2014. The questionnaire consisted of general characteristics of the subjects, subjective health status, oral health behaviors, and needs of oral health. The data were analyzed using SPSS 18.0 program. Results: The long-term patients reported that most of them were denture wearers(38.1%), and had oral disease symptoms(62.5%) and xerostomia(65.6%). Most of the long-term patients were ex-smoker(31.3%) and did not receive regular dental check-up(92.5%). They did not know tooth brushing method(31.3%) and brushed their teeth less than twice a day(47.5%). Those who used tooth brush for more than 6 months accounted for 47.5%. Most of them did not use auxiliary oral hygiene devices(85.6%). The patients answered that oral health is not important(6.9%), oral health education is not necessary(7.5%), and oral cleaning(26.3%) should be included in oral health education. Conclusions: The self-reported oral health status of the long-term patients much more serious than the general population. It is necessary to educate the continuing oral health management program for the long-term patients.