• Title/Summary/Keyword: Alternation

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Alternation in the Cell-mediated Immune Reaction by Bisphenol A Exposure in vitro (In vitro에서 Bisphenol A 노출에 의한 세포성 면역반응의 변화)

  • Pyo Myoung-Yun
    • YAKHAK HOEJI
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    • v.49 no.1
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    • pp.92-96
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    • 2005
  • In order to investigate the effects of bisphenol A (BPA) on cell mediated immune reaction in vitro we examined the allogenic mixed lymphocyte reaction (MLR), splenocytes proliferation (SP) to T cell mitogens and IFN-${\gamma}\;production$. Splenocytes of Balb/c mice ($1.5{\times}10^5$ cells/well) were co-cultured with different numbers of mitomycin C-treated mature dentritic cells (DCs) in presence of BPA (25, 50, 100 ${\mu}M$) and $[^{3}H]$thymidine incorporation (cpm) was measured by scintilation counting. Splenocytes ($2{\times}10^6$ cells/well) were cultured with mitogens, Con A ($2\;{\mu}g/ml$), PHA ($5\;{\mu}g/ml$) and IL-2 ($0.1\;{\mu}g/ml$), or PMA ($5\;{\mu}g/ml$) and INO ($1\;{\mu}g/ml$) in presence of BPA (1, 10, 25, 50, 100 ${\mu}M$) and SP was assessed by MTT assay. $IFN-{\gamma}$ levels in culture supernant were determined by ELISA. At low concentration, BPA slightly increased MLR, SP and $IFN-{\gamma}$ levels, but at higher concentration it showed significant inhibitory effects on these immunological parameters. These results indicate that BPA is able to alternate cell-mediated immune reaction.

Study on Application of Shaft Box type Balcony for Improvement of Ventilation Performance in Apartment (공동주택의 환기성능 개선을 위한 Shaft Box형 발코니의 적용성 검토)

  • Roh, Ji-Woong;Kim, Gon
    • KIEAE Journal
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    • v.7 no.6
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    • pp.3-8
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    • 2007
  • Recently, because of the continuous rise of international oil price, energy saving is strongly demanding. So, Ecological technics of architecture such as use of natural energy have been actively explored in the field of building. In the method of utilizing natural energy, the key point is to saving energy effectively as not lowering the comfort of indoor environment, various systems investigated. Many papers about double skin facade system have been reported, it is announced broadly that the system is very effective in improvement of natural ventilation and indoor thermal environment, and also protecting outdoor sound. The shaft box facade is a special form of box window construction. It consists of a system of box windows with continuous vertical shafts that extend over a number of stories to create a stack effect. The facade layout consists of an alternation of box windows and vertical shaft segments. This research investigated the natural ventilation performance of shaft box type balcony which conform the shaft box type double skin to the exiting balcony construction. First, analyzed various types of exiting apartments, proto-type was decided. By using virtual environment Program, modeling the proto-type, compared the contribution of air temperature and the effect of outdoor air cooling. by this research, we confirmed that shaft box type balcony had many possibility for improvement of indoor environment.

Effects of Chloride Concentration on Zinc Electroplating (염화물의 농도가 전기아연도금에 미치는 영향)

  • Kim, Jae-Min;Lee, Jung-Hoon;Kim, Yong-Hwan;Kim, Young-Ha;Hong, Moon-Hi;Jeong, Hwon-Woo;Chung, Won-Sub
    • Journal of the Korean institute of surface engineering
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    • v.43 no.2
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    • pp.51-56
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    • 2010
  • The zinc electroplating with respect to the chloride concentration was investigated by X-ray diffraction(XRD), scanning electron microscope (SEM), and cathodic polarization measurement. The cathodic overpotential during electroplating was first decreased and then increased with increase of chloride concentration in electrolyte. The decreased cathodic overpotential leads to preferred orientation of (002) plane, high current efficiency and satisfactory zinc deposits. The increased cathodic overpotential causes random orientation, low current efficiency and edge burning. The cathodic overpotential was affected by chloride concentration in electrolyte, not by the kind of chloride, such as NaCl and KCl. An optimized chloride concentration was 3 M for zinc electroplating. Also, it is considered that NaCl can be a alternation for KCl as a main salt of zinc electroplating bath.

A study on MOS Characteristics of 2'nd Silicidation Process (2단계 실리사이드 형성방법에 의한 MOS 공정특성 연구)

  • Eom, Gum-Yong;Han, Gi-Kwan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.195-196
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    • 2005
  • In recent years, as the needs of MOS's a high quality is desired to get the superior electrical characteristics and reliability on MOSFET. As an alternative gate dielectric have drawn considerable alternation due to their superior performance and reliability properties over MOSFET, 2'nd silicidation formation process has been proposed as a dielectric growth/annealing process. In this study the author observed process characteristics on MOS structure. In view points of the process characteristics of MOS capacitor, the oxygen & polysilicon was analyzed by SIMS analysis on l'st & 2'nd Ti process, the oxygen and Si2 contents[Count/sec] of 1.5e3 & 3.75e4 on l'st process and l.1e3 & 2.94e4 on 2'nd process, the Ti contents' of 8.2e18 & 6.5e18 on 1'st and 2'nd process. The sheet resistance[$\Omega/sq.$] was 4.5 & 4.0, the film stress[dyne/cm 2] of 1.09e10 & 1.075e10 on l'st and 2'nd process. I could achieved the superior MOS characteristics by 2'nd silicidation process.

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Identification of Aecial Host Ranges of Four Korean Gymnosporangium Species Based on the Artificial Inoculation with Teliospores Obtained from Various Forms of Telia

  • Yun, Hye-Young;Lee, Seung-Kyu;Lee, Kyung-Joon
    • The Plant Pathology Journal
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    • v.21 no.4
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    • pp.310-316
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    • 2005
  • The objectives of this study were to identify the aecial host ranges of four Korean Gymnosporangium species, G. asiaticum, G. cornutum, Gjaponicum and Gyamadae, and to verify the morphological characteristics of telia as diagnostic keys to the species. Thirteen Korean Rosaceous woody species were artificially inoculated with teliospores obtained from Juniperus species. There was high specificity between telial and aecial hosts and the fungal species, providing the first experimental proof on host alternation of these rust fungi in Korea. Telia on the witches' broom and on the small galls were identified as new telial characteristics in G asiaticum and in G. yamadae, respectively. Aecial hosts of G. asiaticum and G. yamadae showed varying responses in their susceptibility and in the days required for formation and duration of spermogonia and aecia after inoculation. Four telial host species in Juniperus were confirmed for the first time in Korea, which include J. chinensis var. kaizuka, J. chinensis var. horizontalis and J. chinensis var. globosa for G. asiaticum; and J. chinensis var. kaizuka for G. yamadae.

e-Passport Integrated Authentication Mechanisms with Improved Efficiency (효율성이 강화된 전자여권 통합 인증 메커니즘)

  • Lee, Dong-Bum;Go, Woong;Kwak, Jin
    • Journal of Internet Computing and Services
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    • v.10 no.2
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    • pp.53-63
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    • 2009
  • e-Passport system is new type of emigration and immigration control system and it is a research to introduce the e-Passport Authentication Protocol with Improved Efficiency is lively proceeded over the entire world. The e-Passport's chip has a biometric information and personal identification information, Radio Frequency Identification(RFID) technology is used for communication with the Inspection System(IS). However, the feature of the RFID system may bring about various security threats such as eavesdropping, data forgeries, data alternation, cloning, biometric data-leakage. Therefore, in this paper, we analyse the e-Passport system's authentication protocol to protect vulnerability and proposed e-Passport system's authentication protocol reduce computation. Also, we compared their efficiency.

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Preparation of Pseudotetragonal $ZrO_{0.75}S$ and Its Electric Responses on Temperature and Frequency Related to Microstructural Relaxation

  • Ro, Yeong A;Kim, Seong Jin;Lee, Yu Gyeong;Kim, Ja Hyeong
    • Bulletin of the Korean Chemical Society
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    • v.22 no.11
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    • pp.1231-1235
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    • 2001
  • Pseudotetragonal ZrO0.75S whose space group is P212121 was synthesized and the cell dimensions were a=5.110(2) $\AA$, b=5.110(7) $\AA$, and c=5.198(8) $\AA.$ The space group P212121 seems to be resulted from lowering the symmetry of cubic ZrOS structure with P213 space group by lattice distortion due to the oxygen defects. In the distorted structure, bond shortening between metal-nonmetal by reduction of cell volume and alternation of Zr-Zr distance were observed. Dielectric constant and loss data of the bulk material in temperature range -170 to 20 $^{\circ}C$ and frequency range 50 Hz to 1 MHz showed that there was dielectric transition at around -70 $^{\circ}C$ originated from the relaxation of Zr-S segment. Comparing with ZrO2 exhibited the dielectirc constants, 9.0 at room temperature, ZrO0.75S showed high dielectric constant, k = 200.2 at 100 kHz. The activation energy of relaxation time due to dielectric relaxation of Zr-S was 0.47 eV (11.3 kcal/mole). According to the impedance spectra, ZrO0.75S showed more parallel circuit character between the resistance and capacitance components at the temperature (-70 $^{\circ}C)$ that the Zr-S dielectric relaxation was observed.

A Study on the Standards of Open Information About Telecommunications Facilities for Promoting FTTH Investment (FTTH망 투자 촉진을 위한 전기통신설비의 정보제공 기준에 관한 연구)

  • Cho, Eun-jin;Kweon, Soo-cheon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.674-677
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    • 2009
  • The one of the big issues in fixed markets is the investment of next generation networks. The nation-wide incumbent has provided the copper cable based access networks in so far. However in the future multiple providers participant in investing network in first stage of the network investment like mobile networks. Each NRA makes efforts on the resolving construction cost of civil engineering costs through the opening conduits. To smooth operation, information opening service is needed then NRAs must determined the level of opened information and cost of usage information and so on. This paper proposed the alternation of the issues to boost the investment of the next generation networks.

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Sclerotiorin: a Novel Azaphilone with Demonstrated Membrane Targeting and DNA Binding Activity against Methicillin-Resistant Staphylococcus aureus

  • Dasagrandhi, Chakradhar;Pandith, Anup;Imran, Khalid
    • Microbiology and Biotechnology Letters
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    • v.48 no.4
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    • pp.429-438
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    • 2020
  • The emergence of multi-drug resistant, pathogenic methicillin-resistant Staphylococcus aureus (MRSA) is a threat to global health and has created a need for novel functional therapeutic agents. In this study, we evaluated the underlying mechanisms of the anti-MRSA effect of an azaphilone pigment, sclerotiorin (SCL) from Penicillium sclerotiorum. The antimicrobial activity of SCL was evaluated using agar disc diffusion, broth microdilution, time-kill assays and biophysical studies. SCL exhibits selective activity against Gram positive bacteria including MRSA (range, MIC = 128-1028 ㎍/ml) and exhibited rapid bactericidal action against MRSA with a > 4 log reduction in colony forming units within three hours of administration. Biophysical studies, using fluorescent probes and laser or electron microscopy, demonstrated a SCL dose-dependent alternation in membrane potential (62.6 ± 5.0.4% inhibition) and integrity (> 95 ± 2.3%), and the release of UV260 absorbing materials within 60 min (up to 3.2 fold increase, p < 0.01) of exposure. Further, SCL localized to the cytoplasm and hydrolyzed plasmid DNA. While in vitro checkerboard studies revealed that SCL potentiated the antimicrobial activity of topical antimicrobials such as polymixin, neomycin, and bacitracin (Fractional Inhibitory Concentration Index range, 0.26-0.37). Taken together these results suggest that SCL targets the membrane and DNA of MRSA to facilitate its anti-MRSA antimicrobial effect.

A study on the forecasting of container cargo volumes in northeast ports by development of competitive model (컨테이너 항만간의 경쟁 상황을 고려한 물동량예측에 관한 연구)

  • K.T.Yeo;Lee, C.Y.
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 1998.10a
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    • pp.263-269
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    • 1998
  • The forecasting of container cargo volumes should be estimated correctly because it has a key roles on the establishment of port development planning, and the decision of port operating system. Container cargo volumes have a dynamic characteristics which was changed by effect of competitive ports. Accordingly forecasting was needed overall approach about competitive port's development, alternation and information. But, until now, traffic forecasting was not executed according to competitive situation, and that was accomplished at the point of unit port. Generally, considering the competition situation, simulation method was desirable at forecasting because system's scale was increased, and the influence power was intensified. In this paper, considering this situation, the objectives can be outlined as follows. 1) Structural model constructs by System dynamics method. 2) Structural simulation model develops according to modelling of competitive situation by expended SD method which included HEP(Hierarchical Fuzzy Process) And actually, effectiveness was verified according to proposed model to major port in northeast asia.

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