• Title/Summary/Keyword: AT&T

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Immunohistochemical Study on the Suppression of Cell mediated immunity in Lymph node of mouse by Cyclosporin A -Based on the change of T lymphocytes, Il-2 receptors, and NK cells- (Cyclosporin A로 유도된 생쥐 림프절의 세포성 면역억제에 관한 면역조직화학적 연구 -T 림프구, IL-2 수용기 및 NK세포의 변화를 중심으로-)

  • Kim, Jin-Taek;Park, In-Sick;Ahn, Sang-Hyun;Choi, Nan-Hee;Kim, Dong-Hoan
    • The Journal of Dong Guk Oriental Medicine
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    • v.6 no.2
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    • pp.99-107
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    • 1998
  • Cyclosporin A(CsA) is a selective immunosuppressive agent that has been credited with improved survival of solid organ allografts. Lymph node of BALB/C mouse administered CsA immunohistochemically observed to understand immunosuppressive effects of CsA on T lymphocytes, IL-2 receptors, and natural killer NK cells in lymph node. CsA orally administered daily for 10days at the dose 45mg/kg/day/. The lymph node were obtained at day 3, 7, and 14 after CsA administration and embedded with paraffin, and then stained by following ABC method that used monoclonal antibody including L3T4(CD4), Ly2(CD8), IL-2R(CD25), and NK-1.1(CD56). There were little changes of reactive degree and number of helper T lymphocytes, cytotoxic T lymphocytes, IL-2 receptors, and NK cells at day 3 after CsA administration, but they began to decrease at day 7. These decrease were greatest at day 14. The helper T lymphocytes. cytotoxic T lymphocytes, IL-2 receptors, and NK cells distributed in paracortex and medullary sinus. These results indicated that the secretion of IL-2 began to decrease at day 7 after CsA administration and subsequently to suppress T lymphocytes and NK cell as components of cell-mediated immunity.

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Evaluation of Kinetic Parameters and Thermal Stability of Melt-Quenched BixSe100-x Alloys (x≤7.5 at%) by Non-Isothermal Thermogravimetric Analysis

  • Ahmad, Mais Jamil A.;Abdul-Gader Jafar, Mousa M.;Saleh, Mahmoud H.;Shehadeh, Khawla M.;Telfah, Ahmad;Ziq, Khalil A.;Hergenroder, Roland
    • Applied Microscopy
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    • v.47 no.3
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    • pp.110-120
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    • 2017
  • Non-isothermal thermogravimetry (TG) measurements on melt-quenched $Bi_xSe_{100-x}$ specimens (x=0, 2.5, 7.5 at%) were made at a heating rate ${\beta}=10^{\circ}C/min$ in the range $T=35^{\circ}C{\sim}950^{\circ}C$. The as-measured TG curves confirm that $Bi_xSe_{100-x}$ samples were thermally stable with minor loss at $T{\leq}400^{\circ}C$ and mass loss starts to decrease up to $600^{\circ}C$, beyond which trivial mass loss was observed. These TG curves were used to estimate molar (Se/Bi)-ratios of $Bi_xSe_{100-x}$ samples, which were not in accordance with initial composition. Shaping features of conversion curves ${\alpha}(T)-T$ of $Bi_xSe_{100-x}$ samples combined with a reliable flow chart were used to reduce kinetic mechanisms that would have caused their thermal mass loss to few nth-order reaction models of the form $f[{\alpha}(T)]{\propto}[1-{\alpha}(T)]^n$ (n=1/2, 2/3, and 1). The constructed ${\alpha}(T)-T$ and $(d{\alpha}(T)/dT)-T$ curves were analyzed using Coats-Redfern (CR) and Achar-Brindley-Sharp (ABS) kinetic formulas on basis of these model functions, but the linearity of attained plots were good in a limited ${\alpha}(T)-region$. The applicability of CR and ABS methods, with model function of kinetic reaction mechanism R0 (n=0), was notable as they gave best linear fits over much broader ${\alpha}(T)-range$.

Two-Phase Flow through a T-Junction

  • Tae Sang-Jin;Cho Keum-Nam
    • International Journal of Air-Conditioning and Refrigeration
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    • v.14 no.1
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    • pp.28-39
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    • 2006
  • Two-phase flow through a T-junction has been studied by numerous researchers so far. The dividing characteristics of the gas and liquid phases at the T-junction are very complicated due to a lot of related variables. The prediction models have been suggested by using experimental data for a specific condition or working fluid. But, they showed the application limitation for the most of the other conditions or fluids. Since most of them are applicable for their own experimental range, the generalized model for the wide range of conditions and fluids is needed. Even though it's not available now, some of the models developed for air-water flow at a T-junction might be applicable for the part of refrigerants with some modifications. Especially, for the two-phase flow of refrigerants at the T-junction, very few studies have been performed. Further experimental study is required to be performed for the wide range of test conditions and fluids to predict properly the two-phase flow distribution and phase separation through the T-junction.

Characteristics of Pollutants Concentrations at Paddy Field Areas during Irrigation Periods (관개기 광역논에서의 오염물질의 농도 특성)

  • 김진수;오승영;김규성;권순국
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.43 no.6
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    • pp.163-173
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    • 2001
  • This study describes the characteristics of concentrations of pollutants such as total nitrogen(T-N), total phosphorous(T-P), and chemical oxygen demand(COD) at paddy areas during 2-year irrigation periods. The most common order in average concentrations of T-P and COD is podded water > irrigation(or drainage) water > percolated water. Most of pollutants concentrations in drainage water are lower than those in irrigation water after early July due to large uptake of pollutants by rice crop and denitrification. The exponential L (load)-Q(discharge) equations for classified irrigation periods are significant at 0.001 level for irrigation and drainage waters. For drainage water, the concentrations of T-N and COD slightly decrease with discharge, while the T-P concentrations slightly increase with discharge.

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A Study on the Treatment of Nutrients and Organic Carbon in Wastewater through Spatial Separation and Internal Recycling in a Modified Oxidation Ditch (격벽에 의한 조분리와 내부반송을 이용한 산화구 시설의 고도처리개선에 관한 연구)

  • Lee, Young-Shin;Oh, Dae-Min
    • Journal of Environmental Health Sciences
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    • v.37 no.1
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    • pp.64-72
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    • 2011
  • This study was performed to assess the removal efficiency on nitrogen, phosphorus and organic carbon in wastewater by spatial separation and internal recycling in a modified oxidation ditch process (modified OD). The performances of the modified OD were evaluated via laboratory-scale experiments. The process was operated at hydraulic retention times of 6-48 hours and solid retention times of 17-38 days. We found that organic carbon removal efficiency increased after the modified OD operation period. T-N removal efficiency remained stable; average T-N concentration of effluent was 8.02 mg/l after modified OD operation. In contrast, T-P concentration of effluent was over 1 mg/l. Nitrogen and phosphorus removal efficiency of modified OD at HRT 12 hr were 83.1% and 74.1%, respectively. Also, maximum efficiency was found at SRTs from 20 to 30 days. T-N removal efficiency was 83.1% at a C/N ratio from 3.0 to 3.5. However, T-N removal efficiency decreased at C/N ratios over 3.5. Also, T-P removal efficiency increased with HRT at C/P ratios in the same condition. Maximum efficiency was 74.1% at a C/P ratio from 25 to 28. T-N removal efficiency was 79.2% and T-P removal efficiency was 65.3% after M4 mode operation (added to the internal recycle line connected to the anoxic reactor). The modified OD with spatial separation and internal recycling developed in this study is, therefore, believed to be an improvement for solving problems in the nutrient removal technologies.

Development and Verification of the Fog Stability Index for Incheon International Airport based on the Measured Fog Characteristics (인천국제공항의 안개 특성에 따른 안개 안정 지수 FSI(Fog Stability Index) 개발 및 검증)

  • Song, Yunyoung;Yum, Seong Soo
    • Atmosphere
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    • v.23 no.4
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    • pp.443-452
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    • 2013
  • The original Fog Stability Index (FSI) is formulated as FSI=$2(T-T_d)+2(T-T_{850})+WS_{850}$, where $T-T_d$ is dew point deficit (temperature-dew point temperature), $T-T_{850}$ is atmospheric stability measure (temperature-temperature at 850 hPa altitude) and $WS_{850}$ is wind speed at 850 hPa altitude. As a way to improve fog prediction at Incheon International Airport (IIA), we develop the modified FSI for IIA, using the meteorological data at IIA for two years from June 2011 to May 2013, the first one year for development and the second one year for validation. The relative contribution of the three parameters of the modified FSI is 9: 1: 0, indicating that $WS_{850}$ is found to be a non-contributing factor for fog formation at IIA. The critical success index (CSI) of the modified FSI is 0.68. Further development is made to consider the fact that fogs at IIA are highly influenced by advection of moisture from the Yellow Sea. One added parameter after statistical evaluation of the several candidate parameters is the dew point deficit at a buoy over the Yellow Sea. The relative contribution of the four parameters (including the new one) of the newly developed FSI is 10: 2: 0.5: 6.4. The CSI of the new FSI is 0.50. Since the developmental period of one year is too short, the FSI should be refined more as the data are accumulated more.

SOME LOCAL SPECTRAL PROPERTIES OF T AND S WITH AT - SA = 0

  • Yoo, Jong-Kwang;Han, Hyuk
    • Journal of applied mathematics & informatics
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    • v.26 no.5_6
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    • pp.1263-1272
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    • 2008
  • Let T and S be bounded linear operators on Banach spaces X and y, respectively. A linear map A : X ${\rightarrow}$ y is said to be an intertwiner if AT - SA = 0. In this paper we study the relation between local spectral properties of T and S on the assumption of AT - SA = 0. We give some example of intertwiner with T and S.

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MAXIMUM SUBSPACES RELATED TO A-CONTRACTIONS AND QUASINORMAL OPERATORS

  • Suciu, Laurian
    • Journal of the Korean Mathematical Society
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    • v.45 no.1
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    • pp.205-219
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    • 2008
  • It is shown that if $A{\geq}0$ and T are two bounded linear operators on a complex Hilbert space H satisfying the inequality $T^*\;AT{\leq}A$ and the condition $AT=A^{1/2}TA^{1/2}$, then there exists the maximum reducing subspace for A and $A^{1/2}T$ on which the equality $T^*\;AT=A$ is satisfied. We concretely express this subspace in two ways, and as applications, we derive certain decompositions for quasinormal contractions. Also, some facts concerning the quasi-isometries are obtained.

Comparison of Image Quality in Magnetic Resonance Imaging of the Abdominal Organ at 1.5T and 3.0T before the Gadolinium Injection (조영제 주입 전 1.5T 와 3.0T를 이용한 복부장기 자기공명영상에서 영상의 질 비교)

  • Goo, Eun-Hoe
    • Journal of the Korean Society of Radiology
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    • v.11 no.7
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    • pp.619-625
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    • 2017
  • The sudy was intended to evaluate the optimal equipment selection by quantitatively assessing the SNR(signal to noise ratio) and CNR(contrast to noise ratio) on the abdominal organ. This study performed on 1.5 T and 3.0 T MRI units focusing on HASTE, HASTE(f/s) and FFE(in of phase), FFE(out of phase) without using the contrast medium(Gadolinium). The data analysis was performed by randomly selecting on 1.5 T and 3.0 T abdominal MRI images. As a results, SNR and CNR values of 3.0 T is higher than 1.5 T at liver, kidney and spleen(p<0.05). Stomach, abdominal fat and pancreas was obtained a higher value at 1.5 T(p<0.05). On conclusion, the organs of outer part in the body showed generally a high value at 3.0 T, and the organs of inner part in the body including the gas showed a high value at 3.0 T because of a large difference on magnetic susceptibility.

Effects of Supplementing Coated Vitamin C+E with Cottonseed on Rumen Fermentation and Growth Performance and Blood Metabolites in Hanwoo Steers Fed Fermented Feedstuff (발효사료에 대한 보호처리한 Vitamin C+E 및 면실의 첨가가 반추위 발효특성과 거세한우의 육성성적 및 혈액성상에 미치는 영향)

  • 박병기;홍병주;김창혁;라창식;신종서
    • Journal of Animal Science and Technology
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    • v.48 no.6
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    • pp.861-870
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    • 2006
  • This study was conducted to examine the effects of supplementing coated vitamin C+E with cottonseed on rumen fermentation and body weight gain, blood metabolites and hormone concentrations in Hanwoo steers fed fermented feedstuff. Experiments were done with two treatment groups, T1 without any supplements and T2 supplemented with coated vitamin C+E and cottonseed. Ruminal pH was lower in T2 than in T1 at 3h after morning feeding (p<0.05), but was higher in T2 than in T1 at 6 and 9h after morning feeding (p<0.05). Ruminal ammonia concentration was higher in T2 than in T1 for 12h after morning feeding (p<0.05). Concentrations of acetate, propionate, butyrate and total-VFA were higher in T2 than in T1 at 3h after morning feeding (p<0.05), but were lower in T2 than in T1 at 9 and 12h after morning feeding (p<0.05). Average daily gain and concentrations of blood metabolites and hormones between T1 and T2 were similar. Results indicate that supplementation of coated vitamin C+E and cottonseed to fermented feedstuff affects on ruminal pH, ammonia and VFA. But it has no influences on body weight gain and concentrations of blood metabolites and hormones in Hanwoo steers.