• 제목/요약/키워드: AR(l)

검색결과 415건 처리시간 0.033초

Adenophora remotiflora protects human skin keratinocytes against UVB-induced photo-damage by regulating antioxidative activity and MMP-1 expression

  • Kim, Hye Kyung
    • Nutrition Research and Practice
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    • 제10권4호
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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.

중첩된 이동 네트워크 환경에서 빠른 경로 최적화를 지원하는 핸드오프 방안 (Network Mobility Handoff Scheme to Support Fast Route Optimization in Nested Network Mobility)

  • 이일호;이준호
    • 한국컴퓨터정보학회논문지
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    • 제14권5호
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    • pp.119-131
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    • 2009
  • 기존 경로 최적화 방안들은 최적화된 경로가 형성되기까지 경로 최적화 소요시간 이외에 3계층 핸드오프 소요시간도 포함되어 이동 라우터(Mobile Router:MR)의 이동이 빈번한 환경에서는 빠른 경로 최적화가 어렵다는 단점을 가진다. 본 논문에서는 MR이 중첩된 이동 네트워크 환경으로 이동하더라도 별도의 경로 최적화 과정이 없어도 즉시 경로 최적화를 지원하는 3계층 핸드오프 방안을 제안하고자 한다. 이를 위해 제안한 방안에서는 MR과 액세스라우터(Access Router:AR)간의 위치등록과정을 통해 AR로 하여금 MR들의 주소정보를 획득하는 과정을 갖도록 하였다. 이 후 AR은 MR이 수행해야할 홈 에이전트(Home Router:HA)와의 위치등록과정을 대신 수행해줌으로써 AR과 MR의 HA들 사이에 양방향 터널이 형성되고, 패킷들은 해당 목적지 MR의 HA만 경유한 후 AR로 전송된다. 성능평가 결과, 본 논문에서 제안한 3계층 핸드오프 방식은 Reverse Routing Header(RRH), Optimization NEMO(ONEMO) 방안보다 약 $0.6{\sim}1.5[s]$ 감소된 소요시간으로 경로 최적화를 지원할 수 있음을 확인할 수 있었다.

AR(l) 공정을 탐지하는 VSS $\overline{A}$ 관리도의 통계적 설계 (Statistical Design of VSS $\overline{A}$ Charts for Monitoring an AR(1) Process)

  • 이재헌
    • 품질경영학회지
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    • 제31권3호
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    • pp.126-135
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    • 2003
  • A basic assumption in standard applications of control charts is that the observations are statistically independent. However, this assumption is often violated from processes in many industries. The presence of autocorrelation has a serious impact on the performance of control charts, causing a dramatic increase in the frequency of false alarms. This paper considers a process in which the observations can be modeled as a first order autoregressive(AR(1)) process, and develops (equation omitted) charts with the variable sample size(VSS) scheme for monitoring the mean of this process.

EFFECT OF ARGON AND OXYGEN PLASMAS ON VARIOUS POLYETHYLENE SHEETS

  • Chen, Yashao;Hirayama, Naoki;Gomi, Masaki;Kiuchi, Kenji;Momose, Yoshihiro
    • 한국표면공학회지
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    • 제32권3호
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    • pp.344-350
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    • 1999
  • The surface chemical structure of three kinds of polyethylene (PE): high density (HD) PE, low density (LD) PE and linear (L)-LDPE exposed to Ar and $O_2$ plasmas has been investigated using XPS. Oxygen was incorporated in a more increased amount for HDPE than for L-LDPE and LDPE. Ar plasma tended to incorporate more oxygen than $O_2$ plasma. The XPS valence band spectra for Ar plasma exhibited a clear peak assigned to $O_2$s character. By chemical derivatization method it was found that the amount of -COOH group at the surface was much greater than that of -OH group. The hydrophilic nature of plasma-treated PE increased in the order: LDPE

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메밀 및 다시마를 포함하는 유산균 발효액의 생리적 기능 (Physiological Functions of Lactic Acid Bacteria Fermented Broth Containing Fagopyrum esculentum and Saccharina japonica)

  • 전숭종;김애령;이종환
    • 생명과학회지
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    • 제25권10호
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    • pp.1110-1114
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    • 2015
  • 본 연구에서는 각종 곡물(메밀, 귀리, 검은깨, 검은콩, 율피, 현미, 보리, 들깨, 밀) 및 다시마를 포함하는 Lactobacillus brevis AR1의 발효물 중에서 섬유아세포의 콜라겐 합성을 촉진하는 화장품 소재를 조사하였다. 그결과 메밀 및 다시마를 포함하는 Lb. brevis AR1의 발효물을 처리한 섬유아세포에서 효과적으로 콜라겐 합성이 증가하였다. 특히, 다시마 함유 Lb. brevis AR1의 발효물은 양성 대조구인 β-glucan 보다 높은 콜라겐 합성능을 나타내었다. Lb. brevis AR1은 메밀 또는 다시마와 함께 4% MSG를 첨가한 배지에서 72시간 배양한 후, 180 mM의 GABA를 생산하여 84.5%의 GABA 전환율을 나타내었다. 메밀 및 다시마를 포함하는 Lb. brevis AR1의 발효물은 생쥐 피부의 염증 반응을 감소시키는 효과를 가졌고 섬유아세포에서는 세포 독성을 나타내지 않았다. 이 결과들은 메밀 및 다시마를 포함하는 Lb. brevis AR1의 발효물이 피부 주름 개선과 항염증 효과를 가지는 기능성 화장품 소재로서 사용될 수 있다는 것을 나타낸다.

Vitamin D serum levels in children with allergic and vasomotor rhinitis

  • Lee, Seung Jin;Kang, Bong Hwa;Choi, Bong Seok
    • Clinical and Experimental Pediatrics
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    • 제58권9호
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    • pp.325-329
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    • 2015
  • Purpose: In addition to regulating calcium and phosphorus homeostasis and bone metabolism, vitamin D is known as an immune modulator. Recently, there has been increased worldwide interest in the association between low levels of vitamin D and allergic diseases. The purpose of this study was to assess the relationship between serum vitamin D levels and allergic/vasomotor rhinitis (AR/VR) in children. Methods: This study included 164 patients. The sample included 59 patients with AR, 42 patients with VR, and 63 controls. Their ages ranged from 0 to 16 years. We examined the levels of 25-hydroxyvitamin D, Immunoglobulin E, specific IgE, and eosinophil cationic protein; peripheral blood eosinophil count; and the results of a skin prick test. Results: Serum 25-hydroxyvitamin D levels were $19.0{\pm}8.5ng/mL$ in the AR group, $25.5{\pm}10.9ng/mL$ in the VR group, and $26.9{\pm}10.7ng/mL$ in the control group. After adjustment for body mass index and season at the time of blood sampling, vitamin D levels in the AR group were lower than those of the VR group (P=0.003) and control group (P<0.001). Vitamin D levels were inversely correlated with Immunoglobulin E levels (r=-0.317, P<0.001). AR patients with food allergy or atopic dermatitis did not have lower levels of 25-hydroxyvitamin D than AR patients without these diseases. Conclusion: This study demonstrates a possible relationship between vitamin D levels and allergic rhinitis in Korean children.

다결정 Si ingot 응고 시 도가니 열전도도 및 Ar 유입량 변화에 대한 열유체 해석 (Heat and Fluid Flow Analysis on the Effect of Crucible Heat Conductivity and Flow Rate of Ar to Solidification of Polycrystalline Silicon Ingot)

  • 신상윤;예병준
    • 한국주조공학회지
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    • 제32권6호
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    • pp.276-283
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    • 2012
  • This study presents the results on the changes of crucible thermal conductivity and inflow of Ar, and constructed the mathematical model about heat transfer into furnace. As process variables, simulation model was designated thermal conductivity of crucible to $0.5W{\cdot}m^{-1}{\cdot}K^{-1}$, $1W{\cdot}m^{-1}{\cdot}K^{-1}$, $2W{\cdot}m^{-1}{\cdot}K^{-1}$, $4W{\cdot}m^{-1}{\cdot}K^{-1}$, and inflow rate of Ar to 15 L/min, 30 L/min, 60 L/min. Initial condition and boundary condition were set respectively in two terms of process. Each initial conditions were set up by the preceding simulation of heat and fluid flow. The primary goal is the application of unidirectional growth of Si ingot using the result. In the result of the change of heat conductivity of crucible, the higher thermal conductivity of crucible shows the shorter solidification time and the bigger temperature difference. And the flow patterns are changed with the inflow rate of Ar. Finally, we found that the lower crucible's thermal conductivity, the better crucible is at polycrystalline Si ingot growth. But in case of Ar inflow, it is hard to say about good condition. This data will be evaluated as useful reference used in allied study or process variable control of production facilities.

Structure Activity Relationship of ar-Turmerone Analogues

  • Baik, Kyong-Up;Jung, Sang-Hun;Ahn, Byung-Zun
    • Archives of Pharmacal Research
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    • 제16권3호
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    • pp.219-226
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    • 1993
  • For the analysis of structure relationship of ar-turmerone analogues, the compounds containing the various substituents on the phenyl ring and 1(or 2)-naphthyl group in the place of phenyl of ar-turmerone were prepared and tested their cytotoxicity against HL-60, K-562, and L1210 leukemia cells in vitro. The substituents at para position are methoxy, phenoxy, methyl, trifluoromethyl, fluoro, and chloro. At meta position methoxy, methyl, trifluoromethyl, or chloro groups at ortho position mathoxy or chloro group were introduced. Against HL-60 and K-562 cells, $ED_{50}$ values of the analogues are ranged from 0.8 to $30.0\;\mu{g/ml}$. Againste L1210 cell, these are located more than $20.0\;\mu{g/ml}$. However, 5-carbone-thoxy-2-methyl-6(1-naphthyl)-2-octen-4-one (5n)possesses $ED_{50}$ valuses 0.8, 2.1, $6.5\;\mu{g/ml}$ against HL-60, L1210 cells, respectively. The electronic nature of the substituents on phenyl ring of ar-tumerone dose not affect the biological activity. Therefore the flat structure of aromatic potion of ar-tumerone analogues is the more important factor for their activity rather than its electronic nature. The potentiation of the cytotoxicity with the enlargement of aromatic ring region also supports the importance of the plane structure of this area. The restriction of the single bond rotation between C-6 and aromatic ring through the introduction of substituents at the ortho position of phenyl ring and the increment of size of alkyl group at C-6 position enhances the activity. Therefore the effective conformation should by the one having the orthogonal arrangement between the aromatic ring and the side chain.

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철도차량내의 효율적인 인터넷 서비스를 위한 Stateless 기반의 Care of Address 구성방안 (The Stateless Care of Address Configuration Scheme To Provide an Efficient Internet Service in a Train)

  • 이일호;이준호
    • 한국컴퓨터정보학회논문지
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    • 제14권9호
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    • pp.37-46
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    • 2009
  • 철도차량에 탑재된 이동 라우터(Mobile Router:MR)의 이동방향은 랜덤하게 이동하는 일반 무선단말기와 달리 선로를 따라 양방향 이동으로 제한된다. 따라서 이동라우터와 접속된 액세스 라우터 (Access Router:AR)은 인접한 이웃 AR의 주소정보를 이용하여 이동라우터의 2계층, 3계층 핸드오프 수행 전에 이동라우터 대신 미리 Care of Address(CoA)를 구성할 수 있다. 이동라우터는 현재 접속된 AR에서 어느 AR 영역으로 이동하더라도 이동검출과정 후 현지 AR로부터 새로운 CoA를 즉시 획득할 수 있게 된다. 성능분석결과, 제안한 방안은 Stateless 방식과 달리 별도의 CoA 과정과 주소중복확인절차(Duplicate Address Detection:DAD)를 수행하지 않아 Stateless 방식보다 최소 약 1.8(s), 최대 4.98(s) 빠르게 CoA를 획득할 수 있음을 확인할 수 있었다.

The Role of Substituents of ar-Turmerone for its Anticancer Activity

  • Oh, Won-Geun;Baik, Kyong-Up;Jung, Sang-Hun;Ahn, Byung-Zun
    • Archives of Pharmacal Research
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    • 제15권3호
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    • pp.256-262
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    • 1992
  • For the evaluation of the role of substituents of ar-turmerone for its anticancer activity, ar-turmerone (1a) and its analogs like 2-methyl-6-(4'-methyphenyl)-2-octen-4-one (1b), 2-methyl-6-phenyl-2-hepten-4-one (1c), 2-methyl-6-phenyl-2-octen-4-one (1d) and 2 methyl-6-(trans-4'-methylcyclohexyl)-2-hepten-4-one (1e) were preparedd and their cytotoxic activities against $L_{1210}$ cell were determined. Omission of methyl group at para-position dose not variate the cytotoxicity of ar-turmerone. Elongation of alkyl group at 6-position decreases $ED_{50}$ value. Saturation of aromatic ring of ar-turmerone markedly decreases the cytotoxicity. Therefore the smaller size of alkyl group at 6-position and aromatic ring of ar-turmerone should be essential for exhibiting its anticancer activity.

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