• Journal of Powder Materials
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• v.31 no.2
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• pp.169-179
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• 2024

Colloidal quantum dot (QDs) have emerged as a crucial building block for LEDs due to their size-tunable emission wavelength, narrow spectral line width, and high quantum efficiency. Tremendous efforts have been dedicated to improving the performance of quantum dot light-emitting diodes (QLEDs) in the past decade, primarily focusing on optimization of device architectures and synthetic procedures for high quality QDs. However, despite these efforts, the commercialization of QLEDs has yet to be realized due to the absence of suitable large-scale patterning technologies for high-resolution devices., This review will focus on the development trends associated with transfer printing, photolithography, and inkjet printing, and aims to provide a brief overview of the fabricated QLED devices. The advancement of various quantum dot patterning methods will lead to the development of not only QLED devices but also solar cells, quantum communication, and quantum computers.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.50 no.1
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• pp.67-75
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• 2024

Skin aging progresses due to external factors such as ultraviolet rays and infections. These factors cause skin fibroblasts to secrete proteolytic enzymes, matrix metalloproteinases (MMPs). MMPs induce the degradation of collagen located in the extracellular matrix, directly influencing aging. The stems of Akebia quinata Decaisne have been reported to have antioxidant and anti-inflammatory effects. However, the anti-aging effect of Akebia quinata Decaisne stem ethanol extract (AQSEE) is not known. Therefore, we studied the TNF-α-induced MMP-1 inhibitory effect in human fibroblasts. When the cell viability of AQSEE was confirmed through MTT asaay, it showed no toxicity up to 400 ㎍/mL. The inhibition of MMP-1 mRNA and protein secretion was confirmed through RT-qPCR and ELISA, and results showed a significant decrease at concentrations of 100, 200, 400 ㎍/mL. We also confirmed by Western blotting that phosphorylation of MAPKs signaling pathway and transcription factors was reduced. As a result, phosphorylation of p38, c-Jun, p65 was significantly decreased at all concentrations. DPPH and ABTS assays were performed to confirm the radical scavenging ability of AQSEE, and the results showed a significant decrease at all concentrations. The results of this study confirmed the MMP-1 inhibitory effect and radical scavenging ability, which suggests that it can be used as an anti-aging substance.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2007.05a
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• pp.300-320
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• 2007

정보기술의 발달과 함께 소프트웨어 제품은 모든 산업에 필수요소가 되었고, 품질과 평가에 대한 관심도 점차 증가되고 있다. 하지만 일부 산업에서는 소프트웨어 품질 평가에 대한 사용자들의 만병 통치적 기대, 품질 표준의 부족, 측정을 위한 양질의 데이터 부족, 소프트웨어 분석과 디자인에 대한 공학적 한계로 소프트웨어 품질 평가에 대해 많은 문제점이 지적되고 있다. 국내에서도 의료산업 관련 정보시스템의 오류 및 사용자들의 운영 미숙은 매년 많은 금액의 사회적 비용을 증가시켰고, 병원정보시스템의 품질에 대한 관심을 초래하였다. 특히, 산업적 특성이 강한 병원정보시스템은 성공적 구축을 위해 사용자 중심의 소프트웨어 디자인과 다양한 전문가들의 지식 통합이 필요하며, 정보시스템 품질 측정으로 연구자들과 개발자들의 시스템 설계 혼란을 감소시키는 방법론이 필요하다는 연구들이 등장하고 있다. 대부분의 병원정보시스템이 단편적인 업무처리 위주로 개발 운영되고 있고, 장기적 경영전략이나 임상연구를 위한 분석적 정보처리 기능들은 결여되어 있다. 또한 소프트웨어 재설계나 추가적 개발 에 활용될 수 있는 객관적 품질 기준이 부족하고, 사용자들의 요구사항에 대해 소프트웨어 설계에 있어서 효율적으로 반영되지 못하고 있다. 이에 본 연구는 최근 발표된 병원정보시스템 품질 평가에 대한 연구 경향을 종합하고, 품질 평가에 대 해 효율적으로 활용되고 있는 사용성(Usability)을 기준으로 병원산업의 특수성을 포함한 품질 평가 방법과 품질척도를 제안하고자 한다. 국제표준기구(ISO:International Standards Organization)에서는 품질 특성을 기능성, 신뢰성, 사용성, 효율성, 유지 보수성과 이식성의 특성을 제시하고 있다. 특히 Folmer & Bosch(2004)가 정리한 ISO9126에서는 품질의 특성을 배움의 용이성, 운영의 용이성, 이해성과 매력성으로 분류하였고, ISO9241-11는 효과성, 효율성과 만족성으로 분류하였다. 또한 Shackel(1991)은 배움의 용이성(배움과 시간, 기억력), 효과성(오류, 직무시간), 유연성과 마음가짐으로 분류하고 있다(Shackel, 1991). Nielsen(1997)은 배움의 용이성, 기억의 용이성, 오류, 효율성, 만족성으로 분류하고 있고(Nielsen, 1997), Shneiderman(1998)는 효과성(직무시간, 배움의 시간), 효율성(기억의 지속시간, 오류), 만족도를 품질의 특성으로 분류하였다. 이와 같은 소프트웨어의 품질은 소프트웨어 계획, 개발, 성장과 쇠퇴의 모든 과정에 적용되며, 환경적 변화에 따라 사용자들의 정보욕구를 적절하게 반영하여 만족도를 높이 는 것이라고 요약할 수 있다. 그러나 현재까지 소프트웨어 품질 평가에 대한 연구들 은 보편적인 평가 항목들을 대상으로 측정하여 일반적인 품질기준을 제시하고 있고, 유사한 측정 내용들이 중복되어 있다. 이러한 경향은 산업별 특수성이 강한 소프트웨어에 대해서는 정확한 품질측정이 어려웠고, 품질측정에 대한 신뢰성을 떨어뜨리는 계기가 되었다. 이러한 한계를 극복하고자 나타난 방법론이 최종사용자들의 요구사항을 얼마나 적절하게 시스템에 반영했는지에 대한 사용성(Usability) 측정이다. 사용성에 대한 정의는 사용자들이 실질적으로 일하는 장소에서 직접 사용자들의 시스템 운용실태를 파악하여 문제점을 개선하는 것으로 요약할 수 있다. ISO9124-11에서는 사용성을 "어떤 제품이 구체적인 사용자들에 의해 구체적인 목적을 달성하기 위한 구체적인 사용의 맥락에서 효율성, 효과성을 만족함으로 사용될 수 있는 정도"로 정의하고 있다. 지난 10년간 병원정보시스템 평가에 대한 문헌들을 고찰한 결과 품질 측정의 효과는 정보화에 대한 동기유발과 의료품질을 높이는 게기가 되었으며, 질병에 대한 예방효과도 높은 것으로 조사되었다. 그러나 평가에 대한 인식의 문제, 평가 방법의 신뢰성 부족, 평가 지침과 부분적 평가에 따른 인증의 어려움 평가 결과에 대한 확산과 단편적 연구의 한계 등으로 연구결과에 대한 신뢰도와 활용도는 낮은 것으로 조사되었고, HIS에 대한 연구 빈도와 범위 가 매우 미약하였다. 특히, 품질속성은 같은 용어이지만 연구자에 따라 전혀 다른 측정 내용을 제시하고 있어 효율적인 품질 지표를 제시하는데 많은 혼란을 초래하고 있다. 이러한 품질 평가의 경향은 시스템 설계 및 개발자들에게 필요한 사용자들의 구체적이고 독특한 욕구나 병원정보시스템 환경의 특수성 파악에 한계를 보였으며, 평가 범위도 부분적으로 이루어져 전사적 시스템 설계 및 개발에 중요한 자료를 제공하지 못하고 있다. 이러한 문제점과 한계를 극복하고자 ISO와 같은 품질 표준 속성과 컨텍스트(Context)를 중심으로 사용자에 의한 평가 척도의 설정은 구체적이고 실용적이며 신뢰성 있는 평가 방법이 될 것이다.

• Journal of Nutrition and Health
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• v.47 no.1
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• pp.1-11
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• 2014

Purpose: Several studies have proven that EGCG, the primary green tea catechin, and glucosamine-6-phosphate (PGlc) reduce triglyceride contents in 3T3-L1 adipocytes. The objective of this study is to evaluate the combination effect of EGCG and PGlc on decline of accumulated fat in differentiated 3T3-L1 adipocytes. Methods: EGCG and PGlc were administered for 6 day for differentiation of 3T3-L1 adipocytes. Cell viability was measured using the CCK assay kit. In addition, TG accumulation in culture 3T3-L1 adipocytes was investigated by Oil Red O staining. We examined the expres-sion level of several genes and proteins associated with adipogenesis and lipolysis using real-time RT-PCR and Western blot analysis. A flow cytometer Calibar was used to assess the effect of EGCG and PGluco on cell-cycle progression of differentiating 3T3-L1 cells. Results: Intracelluar lipid accumulation was significantly decreased by combination treatment with EGCG $60{\mu}M$ and PGlc $200{\mu}g/m$ compared with control and EGCG treatment alone. In addition, use of combination treatment resulted in directly decreased expression of $PPAR{\gamma}$, $C/EBP{\alpha}$, and SREBP1. In addition, it inhibited adipocyte differentiation and adipogenesis through downstream regulation of adipogenic target genes such as FAS, ACSL1, and LPL, and the inhibitory action of EGCG and PGlc was found to inhibit the mitotic clonal expansion (MCE) process as evidenced by impaired cell cycle entry into S phase and the S to G2/M phase transition of confluent cells and levels of cell cycle regulating proteins such as cyclin A and CDK2. Conclusion: Combination treatment of EGCG and PGlc inhibited adipocyte differentiation through decreased expression of genes related to adipogenesis and adipogenic and cell cycle arrest in early stage of adipocyte differentiation.

• Journal of Nutrition and Health
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• v.49 no.3
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• pp.135-143
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• 2016

Purpose: Ultraviolet (UV)-induced oxidative stress contributes to several adverse biological effects on skin. Many phenolic phytochemicals have been shown to have antioxidant properties and protect skin cells from UV-induced oxidative damage. In this study, we investigated whether or not Aralia elata (AE) has a protective effect against UVB-induced reactive oxygen species (ROS), ultimately leading to photoaging. Methods: Phenolic content of dried AE and antioxidant properties of AE extract in 70% ethanol weredetermined by measuring DPPH and ABTS radical scavenging activities and ferric reducing antioxidant power (FRAP). The effect of AE extract on cellular ROS generation and expression levels of oxidative stress-response proteins such as superoxide dismutase (SOD)-1, catalase, nuclear factor-erythroid 2-related factor (Nrf)-2, and heme oxygenase (HO)-1 in UVB-irradiated ($75mJ/cm^2$) human keratinocytes (HaCaT) were further determined by 2'-7'-dichlorofluoresceine diacetate assay and Western blotting, respectively. Results: The total phenolic and flavonoid contents of dried AE were 20.15 mg tannic acid/g and 18.75 mg rutin/g, respectively. The $IC_{50}$ of AE extract against DPPH radical was $98.5{\mu}g/mL$, and ABTS radical scavenging activity and FRAP upon treatment with $1,000{\mu}g/mL$ of AE extract were $41.8{\mu}g\;ascorbic\;acid\;(AA)\;eq./mL$ and $29.7{\mu}g\;AA\;eq./mL$,m respectively. Pretreatment with AE extract significantly reduced (p < 0.05) ROS generation compared to that in UVB-irradiated control HaCaT cells. Pretreatment with AE extract reversed reduction of Nrf-2 and SOD-1 protein expression and induction of HO-1 protein expression caused by UVB exposure in HaCaT cells, whereas it did not affect catalase expression. Conclusion: AE extract in 70% ethanol demonstrated a protective effect against UVB-induced oxidative stress and decreased expression of Nrf-2 and SOD-1 in human keratinocytes. These findings suggest that AE ethanol extract might have potential as a natural resource for a skin anti-photoaging product in the food and cosmetic industry.

• The Korean Journal of Pharmacology
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• v.32 no.1
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• pp.113-123
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• 1996

It has been well known that polyamines ensure the stability of chromatin structure and the fidelity of DNA transcription. This study was carried out to evaluate the effect of polyamines on the apoptosis of mouse thymocytes induced by dexamethasone and polyamine synthesis inhibitors. 1) In the histological death findings of thymocytes double-stained with acridine orange and ethidium bromide, the apoptotic and the necrotic fractions (AF; NF) in the control group were $9.4{\pm}4.2%$ and $4.5{\pm}5.3%$, respectively. Dexamethasone $(3\;{\times}\;10^{-8}\;M:\;DX)$ in creased AF upto $52.0{\pm}8.1%$ and did not change NF, but A23187 $(5\;{\times}\;10^{-7}\;M:\;A2)$ increased AF and NF upto $45.0{\pm}8.9%$ and $20.5{\pm}10.6%$, respectively. 2) The thymocyte viability was significantly reduced by DX, DHEA $(1\;{\times}\;10^{-4}\;M)$, A2, DFMO $(1\;{\times}\;10^{-4}\;M)$, and $MGBG\;(1\;{\times}\;10^{-4}\;M)$, respectively. It was, however, little affected by $aminoguanidine\;(1\;{\times}\;10^{-4}\;M:\;AG)$, $putrescine\;(1\;{\times}\;10^{-5}\;M:\;PT)$, $spermidine\;(1\;{\times}\;10^{-5}\;M:\;SD)$, and $spermine\;(1\;{\times}\;10^{-5}\;M:\;SM)$. 3) The genomic DNA of mouse thymocyte was markedly fragmented by DX and A2, respectively, and to a lesser extent, by DHEA, but was little affected by MGBG, DFMO, AG, and each of polyamines. 4) The DX induced reduction of thymocyte viability was moderately attenuated by DHEA, but little affected by DFMO, MGBC, and AG. However, SM significantly attenuated the viability reduction induced by A2 as well as DX. 5) The thymocyte viability reduction by MGBG and DFMO was significantly attenuated by only SM among three polyamines applied in this study. 6) The thymocyte viability redution by combined treatments of DX with DFMO and MGBG, respectively, was significantly attenuated by SM, and moderately by PT. But the viability reduction by combined treatment of DX with AG or DHEA was not affected by polyamines. These results suggest that polyamines, particularly spermine, might play the inhibitory role in thymocyte apoptosis and the inhibitory effect can be ascribed in part to the increase of polyamine uptake by thymocytes pretreated with DFMO and MGBG.

• Management & Information Systems Review
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• v.36 no.5
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• pp.1-26
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• 2017

In the meantime, research on corporate informatization focuses on the completeness of information technology itself and its financial effects, so there is insufficient research on whether information technology can support business strategy. It is necessary to verify whether the management strategy implementation of the company can be led through the informatization of the enterprise and the relation between the main mechanism factors and the informatization performance. In this study, what a mechanism factor is applied in the process of result creation of informatization from three mechanism perspectives such as selecting mechanism, learning mechanism and coordinating mechanism with cases of representative domestic IT company and what an importance mechanism factors have been ascertained. This study results in 8 propositions. For a main agent of companies, securement of information capability of organizations has been selected to realize informatization results and investment of informatization has been selected to solve organizational decentralization problems as the most important factor. Additionally, as competition in the industry gets fierce, investment on informatization has been changed to a utility way of implementation of strategies and decision on investment has been made through the official process and information technology. Differentiated company capability has been made based on acquisition of technical knowledge and company information has been expanded to its whole employees through the information system. Also, informatization change management and outside subcontractor management have been acknowledged as an important adjustment factor of company. The first implication of this study is that since case studies on mechanism factors that preceding studies on informatization results did not empirically cover have directly been dealt with based on experiences of executives in charge of business and in charge of informatization, this study can provide practical views about factors that should be mainly managed for informatization results of IT companies. Secondly, since ser-M framework has been applied for IT companies for the first time, this study can academically contribute to companies in other fields about main mechanism factors for result creation of informatization based on deeper understanding and empirical cases.

• Tuberculosis and Respiratory Diseases
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• v.54 no.5
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• pp.542-550
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• 2003

Background : Synthetic glucocorticoids are widely used in many chronic inflammatory diseases because of their excellent anti-inflammatory activity. Enhancing the transcription of $I{\kappa}B$ and preventing activated NF-${\kappa}B$ from binding to ${\kappa}B$ sites are thought to be the underlying mechanisms. But these data are largely derived from in vitro studies using cell lines. In this study, after administrating a steroid to volunteers, we evaluated the effect on the NF-${\kappa}B$ system. Methods : Prednisolone(0.5mg/kg/d) was orally administered to 5 healthy volunteers for 7 days. Before and after the administration, we sampled their peripheral blood monocytes, and performed western blot analysis both with stimulation, using IL-$1{\beta}$, LPS, TNF, and without stimulation(baseline). We also performed EMSA after stimulation with LPS. Results : After ingestion of the steroid, baseline expressions of $I{\kappa}B{\alpha}$ were increased in two of the subjects, while suppressed degradations of $I{\kappa}B{\alpha}$ to stimulations were observed in all five. In addition, the binding capacity of NF-${\kappa}B$ after the administration was decreased. Conclusion : Steroid plays such roles as enhancing the transcription of $I{\kappa}B{\alpha}$, suppressing the DNA binding capacity of NF-${\kappa}B$, and suppressing the degradation of $I{\kappa}B{\alpha}$.

• (The)Study of the Eastern Classic
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• no.57
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• pp.9-40
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• 2014

This article focuses on Yeheon's consideration and solution for the hostile of social circumstances during the time of the Japanese invasions. Yeheon thought that the Chosun dynasty must have faced such disorder before the war happened. People including the king and his subjects did not live their life according to the righteous principle, and the state was not under control in a way that it should accomplish the Dao. Yeheon thought that the Japanese invasion, which is more like a flood or certain disasters, was not primarily responsible for the harshest of environments. Yeheon paid his attention to the fact that even after the Japanese invasions ended, people were still in disorder losing their mind-and-heart. People's mind-and-heart became that of animals because of starvation and disease. This is because the government made people trapped in a difficult situation by forcing them to prepare for military operations, rather than taking care of them. As a result, in Yeheon's view, the main cause of the social disorder was people's lack of mind-and-heart, which brought about their actions of brutality like those of animals. Although Yeheon himself did not form righteous armies, he instead suggested a right path to overcome and solve the social disorder by describing and analyzing in detail the reality of the war as well as the problems of policies. In particular, Yeheon studied the Zhou yi at the time because understanding the principle of fortune and misfortune, as well as the rise and fall of a state, could give a proper solution to the social turmoil of his times. In Yeheon's eyes, the most important thing to do in the time of people's losing mind-and-heart was to follow li and accomplish the Dao in their daily life. And this was what he, as a gentleman, should do. Yeheon thought that in spite of the harshest of environments, one can still preserve one's grace and dignity, which would overcome one's adversity. This gives us the following questions: should one put aside one's grace and dignity to overcome wartime perils? Or in so doing, one should face more severe time after a short period of peace and stability? These questions concern the relationship between one's morality and the state's responsibility, and what is the right way of doing one's duty to the state is the main philosophical subject in this article.

• 한국노년학
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• v.40 no.4
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• pp.801-821
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• 2020

There are a number of prior studies on the poverty experience of Korean women, but little is known about the poverty experience of Korean elderly women in the U.S. The purpose of this study is to examine the poverty experiences of Korean elderly women who immigrated to the U. S. Qualitative case study methods were used to achieve these research objectives. Three Korean elderly women living in Oakland of California who received Supplemental Security Income (SSI) from the U.S. federal government were included in the study. The data were collected by conducting a total of six meetings per participant, and the researcher read the consent form directly to the participants and obtained a hand-written signature. The analysis and interpretation began by repeating the interview transcript several times, and the repeated keywords were to be understood in the context, focusing on time, space, and relationships with other people. The contextual understanding of Korean elderly women's experiences in poverty was interpreted in three dimensions: extending poverty in their mother country, double torture as female immigrants, and limiting labor due to aging and diseases. Before moving to the U.S., they had a difficult livelihood by farming and one of them had to live in poverty due to the bereavement to her husband. But even after moving to the U.S., they have continued to live in poverty. As female immigrants with low education and no special skills, they were incorporated into the periphery of the labor market in the industrialized U.S. and were forced to make a living with low wages. Korean elderly women were unable to return to the labor market in the surrounding areas due to aging and diseases, and were continuing their impoverished lives relying on SSI. From the findings, we discussed the role of the Korean immigrants community as a way to improve the quality of life for Korean elderly women in the U.S.