• Journal of the Korean Society for information Management
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• v.41 no.1
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• pp.85-105
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• 2024

Augmented Reality (AR) is a mix of the real world that is enhanced by virtual objects from computer-generated information. AR is currently used in a variety of information systems and library services. AR technologies are also being developed for today's children, who are digital natives and are exposed to various technologies even earlier. To assist librarians who need to accurately understand users' information needs and perceptions of the technology being used in their libraries, we conducted a study of AR perceptions among children. We conducted two online co-design sessions using "Would you rather?", a co-design technique that facilitates research into children's opinions. Through the co-design sessions, we found that children were psychologically wary about AR technology due to a lack of trust in the technology, and realism had a significant impact on these judgments. We also identified that children considered AR technology environments as an extension of the real world. Their real-world values directly influenced their perceptions of AR. This research provides insights into the wariness that libraries need to be aware of when developing AR content for children in the future, and how libraries can use AR as an educational tool.

• Nutrition Research and Practice
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• v.10 no.4
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• pp.371-376
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• 2016

BACKGROUND/OBJECTIVES: Chronic ultraviolet (UV) exposure-induced reactive oxygen species (ROS) are commonly involved in the pathogenesis of skin damage by activating the metalloproteinases (MMP) that break down type I collagen. Adenophora remotiflora (AR) is a perennial wild plant that inhabits Korea, China, and Japan. The present study investigated the protective effects of AR against UVB-induced photo-damage in keratinocytes. MATERIALS/METHODS: An in vitro cell-free system was used to examine the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and nitric oxide (NO). The effect of AR on ROS formation, antioxidant enzymes, elastase, MMP-1 level, and mRNA expression of MMP-1 were determined in UVB-irradiated human keratinocyte HaCaT cells. RESULTS: AR demonstrated strong DPPH free radical and NO scavenging activity in a cell-free system exhibiting $IC_{50}$ values of 1.88 mg/mL and 6.77 mg/mL, respectively. AR pretreatment dose-dependently attenuated the production of UVB-induced intracellular ROS, and antioxidant enzymes (catalase and superoxide dismutase) were enhanced in HaCaT cells. Furthermore, pretreatment of AR prevented UVB-induced elastase and collagen degradation by inhibiting the MMP-1 protein level and mRNA expression. Accordingly, AR treatment elevated collagen content in UVB-irradiated HaCaT cells. CONCLUSION: The present study provides the first evidence of AR inhibiting UVB-induced ROS production and induction of MMP-1 as a result of augmentation of antioxidative activity in HaCaT human keratinocytes. These results suggest that AR might act as an effective inhibitor of UVB-modulated signaling pathways and might serve as a photo-protective agent.

• Proceedings of the Petrological Society of Korea Conference
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• 2002.05a
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• pp.1-38
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• 2002

옥천변성대 서남부지역은 변성이질암의 광물조합을 기준으로 남동부부터 북서방향으로 흑운모대, 석류석대, 십자석대의 3개의 변성광물분대로 나누어진다. Oh et al. (1995a)의 연구에서 보고된 남정석들은 산출되지 않는 것이 확인되었고 변성도는 흑운모대에서 석류석대를 거쳐 십자석대로 갈수록 증가한다. 쥬라기 화강암 접촉부의 국부적인 변성암류에서는 화강암에 의한 접촉변성작용에 의해 형성된 홍주석과 규선석이 산출된다. 흑운모대의 변성 압력-온도는 4.2 - 5.1 kb, 400 - 500 $^{\circ}C$이다. 십자석대의 정누대구조를 가지는 석류석과 석류석안의 사장석, 흑운모, 금흥석, 일메나이트포유광물의 공생관계로 추정한 압력-온도 (석류석 주변부: 7.0 - 8.0 kb, 550 - 620 $^{\circ}C$； 석류석 중심부: 4.0 - 5.0 kb, 420 - 520 $^{\circ}C$) 및 십자석대 내에서 후퇴변성작용 및 접촉변성작용 받은 석류석 주변부에 기록된 압력-온도 조건(약 2.0 - 3.0kb, 450 - 55$0^{\circ}C$)과 함께 옥천변성대 서남부지역의 변성암류가 시계방향의 압력-온도 경로를 겪었음을 지시한다. 연구지역 내에서 정밀 기재된 단면들에 대한 퇴적환경을 종합하면 대체 적으로 남동부에서는 천해성 환경이 인지되나 북서쪽으로 갈수록 대륙사면을 거쳐 분지 중심의 환경으로 전이되는 경향을 보인다. 이러한 퇴적상의 공간적 분포는 분지의 남동쪽보다 북서쪽의 침강이 우세하였던 것으로 해석될 수 있으며, 이는 곧 분지가 형성될 때 반지구대 (half graben) 형태로 분지가 열개 (rifting) 되었음을 의미한다. 각 변성분대에서 채취한 변성이질암으로부터 측정된 K-Ar 과 40Ar/39Ar 흑운모와 백운모 연대들은 149 - 167 Ma에 집중된다. 그리고 각 변성분대에서 동일시료에 대한 K-Ar 과 40Ar/39Ar 연대들은 동일시기를 지시함으로 연대적인 신뢰성을 확인 할 수 있었다. 옥천변성대 서남부지역의 변성암류를 관입하는 2개의 괴상의 화강암과 1개의 엽리화강암에서 얻어진 백운모와 흑운모들의 K-Ar 연대는 모두 156 Ma이며 옥천변성대 서남부지역의 변성이 질암의 연대와 유사하다. 이는 연구지역의 변성암류와 화강암류는 40Ar/39Ar 과 K-Ar 계의 흑운모와 백운모의 폐쇄온도 (약 300 - 350 $^{\circ}C$) 까지 동시에 냉각된 사실을 지시한다. 각섬석 편암내의 각섬석들은 복잡한 40Ar/39Ar 연대를 보여주며 일부가 평형연대를 보여주지만 특별한 의미 부여가 힘들다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.281-284
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• 2004

Mean energy of electrons in $SF_6-Ar$ Mixtures Gas used by MCS-BEq algorithm has been analysed over the E/N range $30{\sim}300[Td]$ by a two term Boltzmann equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6-Ar$, 0.1[%] and 5.0[%], $SF_6-Ar$ mixtures were measured by time-of-flight(TOF) method. The transport Coefficients for electrons in (100[%])$SF_6$. (100[%])Ar, (0.2[%])$SF_6-Ar$ and (0.5[%]) $SF_6-Ar$, (5.0[%]) $SF_6-Ar$, (0.1[%])$SF_6-Ar$ mixtures were measured by time-of-flight method, and the electron energy distribution function and the parameters of the velocity and the diffusion were determined by the variation of the collision cross-sections with energy. The results obtained from Boltzmann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

• The Journal of Korean Physical Therapy
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• v.31 no.3
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• pp.141-146
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• 2019

Purpose: To investigate the effect of an augmented reality (AR) system on muscle strength and function level of the paretic lower limb and the balance ability in the early rehabilitation program of acute stroke patients. Methods: The participants (30 or fewer days after stroke) were randomly assigned to receive intervention with an early rehabilitation program using an AR system (n=1) or an early rehabilitation program consisting of functional electrical stimulation and tilt table use (n=1). Patients in both subjects received interventions 4-5 times a week for 3 weeks. Results: In the paretic limb muscle strength, AR subject was increased from 15 to 39.6 Nm and Control subject was increased from 5 to 30.2 Nm. The paretic limb function of AR subject motor function was increased from 8 to 28 score and Control subject motor function was increased from 6 to 14 score. But sensory function was very little difference between the two subjects (AR subject: from 4 to 10 score, Control subject: from 3 to 10 score). In the balance ability, AR subject had more difference after intervention than control subject (AR subject: 33 score, Control subject: 22 score). Conclusion: The early rehabilitation program using the AR system showed a slightly higher improvement in the motor function of the paretic lower limb and balance ability measurement than the general early rehabilitation program. The AR system, which can provide more active, task-oriented, and motivational environment, may provide a meaningful environment for the initial rehabilitation process after stroke.

• The Korea Journal of Herbology
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• v.37 no.1
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• pp.41-50
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• 2022

Objectives : The aim of this study was to investigate the effect of water extract of Agastache rugosa (AR) on productions of inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW 264.7 mouse macrophages. Methods : Cell viabilities were measured with MTT assay. The production of nitric oxide (NO) from RAW 264.7 cells was measured with Griess reagent assay. The production of cytokines in RAW 264.7 cells was measured with multiplex cytokine assay. Results : AR showed no cytotoxicity on RAW 264.7 cells. AR at concentrations of 25, 50, 100, and 200 ㎍/mL significantly inhibited NO production in LPS-stimulated RAW 264.7 cells. AR at concentrations of 50, 100, and 200 ㎍/mL significantly inhibited productions of TNF-α and IL-1β in LPS-stimulated RAW 264.7 cells; AR at concentrations of 50 and 200 ㎍/mL significantly inhibited productions of RANTES (CCL5) in LPS-stimulated RAW 264.7 cells; AR at concentrations of 100 ㎍/mL significantly inhibited productions of macrophage inflammatory protein-1β in LPS-stimulated RAW 264.7 cells; AR at concentrations of 50, 100, and 200 ㎍/mL significantly increased productions of IP-10 (CXCL10) in LPS-stimulated RAW 264.7 cells; AR at concentrations of 100 and 200 ㎍/mL significantly increased MCP-1 (CCL-2) in LPS-stimulated RAW 264.7 cells; AR at concentrations of 50 and 100 ㎍/mL significantly increased productions of IL-10 in LPS-stimulated RAW 264.7 cells. Conclusions : AR might have immunomodulatory effects on productions of NO, cytokines, and chemokines in LPS-stimulated RAW 264.7 mouse macrophages.

• Korean Journal of Optics and Photonics
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• v.14 no.3
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• pp.298-305
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• 2003

We have calculated the single mode yield of index-coupled (IC) DFB lasers above threshold for several kL, and facet reflectivity combinations, and investigated the correlation between those results and the single mode yield as a function of f number at the threshold. As a result, there is little correlation between the single mode yield above threshold and the single mode yield as a function of f number at the threshold. The single mode yields above threshold for kL of 0.8 and 1.25 is larger than those for kL, of 2 and 3 due to the spatial hole burning effect. Also, we have investigated the effect of the reflectivity of the AR facet on the single mode yield for AR-HR and AR-CL combinations. For AR-HR combinations, the single mode yield increases as the reflectivity of the AR facet decreases. However, for AR-CL combinations, the reflectivity of the AR facet for the largest single mode yield exists. In the single mode yield calculations for IC DFB lasers in this paper, the single mode yield for kL of 0.8 with AR(1％)-HR combination is largest above threshold.

• Journal of the Korean Vacuum Society
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• v.8 no.1
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• pp.51-54
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• 1999

Hydrogenated amorphous silicon (a-Si:H) films are fabricated by Argon radical annealing (ArRA). The deposition rate of continuously deposited a-Si:H film is 1.9 $\AA$/s. As ArRA time are increased to 0.5 and 1 minute, the deposition rate are increased to 2.8 $\AA$/s and 3.3 $\\AA$/s. The deposition rate of a-si:H films with 2 and 3 minutes ArRA time are 3.3 $\AA$/s. As the ArRA time is increased, the optical band gap and the hydrogen contents in the a-Si:H films are increased and slightly decreased. The light-induced degradation of ArRA treated a-Si:H films are less than that of continuously deposited a-Si:H film. The dark conductivity and the conductivity activation energy ($E_a$) of continuously deposited a-Si:H film are decreased to 1/25 in room temperature and increased to 0.09eV By 1 hour light soaking, respectively. The dark conductivity and $E_a$ of ArRA treated a-Si:H film decreased to 1/3 in room temperature and increased to 0.03eV by 1 hour light soaking, respectively. We could improve the stability of a-Si:H films under the light soaking by ArRA technique and discussed the microscopic process of ArRA technique.

• Clinical and Experimental Emergency Medicine
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• v.3 no.3
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• pp.175-180
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• 2016

Objective Combination of ${\beta}_1-adrenergic$ receptor (AR) blockade and ${\beta}_2-AR$ activation might be a potential novel therapy for treating heart failure. However, use of ${\beta}-AR$ agonists and/or antagonists in the clinical setting is controversial because of the lack of information on cardiac inotropic or chronotropic regulation by AR signaling. Methods In this study, we performed hemodynamic evaluation by examining force frequency response (FFR), Frank-Starling relationship, and response to a non-selective ${\beta}-AR$ agonist (isoproterenol) in hearts isolated from 6-month-old transgenic (TG) mice overexpressing ${\beta}_1-$ and ${\beta}_2-ARs$ (${\beta}_1-$ and ${\beta}_2-AR$ TG mice, respectively). Results Cardiac physiologic consequences of ${\beta}_1-$ and ${\beta}_2-AR$ overexpression resulted in similar maximal response to isoproterenol and faster temporary decline of positive inotropic response in ${\beta}_2-AR$ TG mice. ${\beta}_1-AR$ TG mice showed a pronounced negative limb of FFR, whereas ${\beta}_2-AR$ TG mice showed high stimulation frequencies with low contractile depression during FFR. In contrast, Frank-Starling relationship was equally enhanced in both ${\beta}_1-$ and ${\beta}_2-AR$ TG mice. Conclusion Hemodynamic evaluation performed in the present showed a difference in ${\beta}_1-$ and ${\beta}_2-AR$ signaling, which may be due to the difference in the desensitization of ${\beta}_1-$ and ${\beta}_2-ARs$.

• Journal of Plant Biotechnology
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• v.5 no.4
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• pp.233-238
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• 2003

Sweet potato cells derived from Yulmi were isolated from embryogenic callus and irradiated with 50 Gy dose. Resistant cells were selected on a MS medium containing 1.0 mM S-aminoethyl-L-cysteine (AEC). This level of AEC approximately inhibits non-selected wild type cells. The callus resistant to this analog of lysine was subcultured for 30 days in absence of AEC to proliferate. The three resistant calli (AR-1, AR-2 and AR-3) with better growth were divvied into 0.5~1mm diameter and placed on MS medium with 0, 0.4, 0.6, 0.8 and 1.0 mM AEC. There are considerable growth difference between control callus and AEC resistant callus on the AEC-medium. The selected calli were placed on the hormone-free medium for regeneration. Three plantlets, five plantlets and six plantlets were recovered from AR-1, AR-2 and AR-3 calli, respectively. Each two regenerants in AR-1, AR-2 and AR3 were randomly selected for RAPD and SDS PAGE analysis. RAPD polymorph isms between Yulmi and AEC resistant plant from irradiated calli were detected in several Wako primers. Also, it was identified that two AEC resistant plants had higher protein than the original variety Yulmi.