• Title/Summary/Keyword: selective

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Effects of Age on Selective Antagonist Binding to Muscarinic Receptors in Rat Striatum

  • Kim, Hwa-Jung;Lee, Sun-Hyoung;Molly H. Weiler
    • Biomolecules & Therapeutics
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    • v.6 no.4
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    • pp.337-344
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    • 1998
  • The objective of the present study was to investigate the effect of senescence on the binding properties of muscarinic receptors in the neostriatum of young (3 months), middle-aged (18 months) and aged (33 months) male Fischer 344 x Brown Norway hybrid rats by employing direct binding of selective radiolabeled antagonists. Using the selective M, muscarinic receptor antagonist, $[^3H]$AF-DX384, as the ligand, no significant difference in the maximal receptor density (Bmax) was observed in the neostriatum among any age-groups. In contrast, with the selective M, receptor antagonist, $[^3H]$4-DAMP, a significant increase in the number of muscarinic receptors was observed in neostriatal membrane fractions prepared from the aged animals relative to that observed in the young rats. For each ligand there was no age-related change in its affinity (Kd) for the muscarinic receptors. These results indicate that the observed age-related changes in the muscarinic receptor density may not be necessarily decremuntal and depend upon the muscarinic receptor subtype examined.

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A Study on the Selective Criteria and Information Soruce of Imported Apparel Brand (해외의류상표 도입시 선택기준과 정보탐색 행동)

  • 권영아
    • Journal of the Korean Society of Costume
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    • v.47
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    • pp.101-112
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    • 1999
  • This study examined 1) retail buyer's reasons for buying imported apparel and brand license business and 2) types of information sources which they searched for the businesses 3) types of product/vendor selective criteria Seventy subjects of one hundred samples responded. They were designers merchandisers of apparel companies and buyers of department stores. The results of empirical studies were summarized as follows: 1) Buyers & merchandisers recognized domestic market responses as the most important information source for selecting foreign brand. The critical problem of buying and brand license was deficiency of professionals in fashion retail 2) Buyers & merchandisers primarily recognized brand identity and exclusive style of the product when selecting puoduct or vendor. 3) Buyers & merchandisers primarily recognized return policy and good delivery of the vendor when selecting vendor 4). There were relationships among incormation sources selective criteria of product/vendor and buyer's characteristics.

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Application of Ion-Selective Electrodes to Measure Ionic Concentrations of Macronutrients in Hydroponics (수경재배 시 다량 이온 농도 측정을 위한 이온 선택성 전극의 응용)

  • Kim, Min-Su;Park, Tu-San;Cho, Seong-In
    • Journal of Biosystems Engineering
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    • v.32 no.1 s.120
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    • pp.37-43
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    • 2007
  • This study was carried out to investigate the applicability of PVC membrane-based ion-selective electrodes for macronutrients (K, Ca, and N) by measuring of potassium, calcium, nitrate ions in hydroponic nutrient solution. The capabilities of two ion-selective membranes with varying chemical compositions for each ion were evaluated in terms of sensitivity, selectivity, and lifetime to choose sensing elements suitable for measuring typical ranges of nutrient concentrations in hydroponic solutions. The selected calcium and nitrate ion-selective membranes showed effectively sensitive responses to calcium and nitrate ions with lifetimes of 25 and 15 days, respectively. The addition of a cation additive to the potassium membrane cocktail allowed its sensitivity to be increased whereas its lifetime was reduced from 30 days to 10 days.

Effect of Process Parameters on Forming Characteristics of Selective Laser Sintered Fe-Ni-Cr Powder (Fe-Ni-Cr 분말의 선택적 레이저 소결 적층시 공정변수에 따른 조형특성)

  • Joo, B.D.;Jang, J.H.;Yim, H.S.;Son, Y.M.;Moon, Y.H.
    • Transactions of Materials Processing
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    • v.18 no.3
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    • pp.262-267
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    • 2009
  • Selective laser sintering is a kind of rapid prototyping process whereby a three-dimensional part is built layer wise by laser scanning the powder. This process is highly influenced by powder and laser parameters such as laser power, scan rate, fill spacing and layer thickness. Therefore a study on fabricating Fe-Ni-Cr powder by selective laser sintering has been performed. In this study, fabrication was performed by experimental facilities consisting of a 200W fiber laser which can be focused to 0.08mm and atmospheric chamber which can control atmospheric pressure with argon. With power increase or energy density decrease, line width was decreased and line surface quality was improved with energy density increase. Surface quality of quadrangle structure was improved with fill spacing optimization.

Efficient Channel Delay Estimation for OFDM Systems over Doubly-Selective Fading Channels

  • Heo, Seo Weon;Lim, Jongtae
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.9
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    • pp.2218-2230
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    • 2012
  • In this paper, we propose an efficient channel delay estimation method for orthogonal frequency-division multiplexing (OFDM) systems, especially over doubly-selective fading channels which are selective in both the symbol time domain and subcarrier frequency domain. For the doubly-selective fading channels in single frequency network (SFN), long and strong echoes exist and thus the conventional discrete Fourier Transform (DFT) based channel delay estimation system often fails to produce the exact channel delay profile. Based on the analysis of the discrete-time frequency response of the channel impulse response (CIR) coefficients in the DFT-based channel delay estimation system, we develop a method to effectively extract the true CIR from the aliased signals by employing a simple narrow-band low-pass filter (NB-LPF). The performance of the proposed system is verified using the COST207 TU6 SFN channel model.

Relationship Between Bilingualism and Selective Attentional Ability in Young Children (이중 언어 경험과 선택적주의능력의 관계)

  • Lee, Hae-Ryoun;Lee, Kwee-Ock
    • Korean Journal of Child Studies
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    • v.27 no.4
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    • pp.55-64
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    • 2006
  • The purpose of this study was to investigate the effects of bilingualism on children's selective attentional ability by comparing Korean-Chinese bilingual with Chinese monolinguals in China. The subjects were 71 children, 4 and 5 years of age, 38 of whom were bilingual while 33 were monolingual. Bilingual children spoke Korean at home but Chinese in the community and at preschool. The instrument used to measure children's selective attentional ability was DCCST (Dimensional Change Card Sorting Task) and ANT (Attentional Network Test). Results showed that bilingual children were more advanced than monolingual in selective attentional ability.

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Effect of Acupotomy with Selective Cryolysis for Localized Fat: Case Report (도침치료와 냉각요법을 병용한 부분 비만의 치료: 증례보고)

  • Yoon, Sang-hoon;Mun, Yong-Jin;Cho, Kyong-Ha
    • Journal of Korean Medicine for Obesity Research
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    • v.15 no.2
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    • pp.149-152
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    • 2015
  • The aim of this study is to report clinical progresses on localized fat. We devised the method of treat localized fat using acupotomy with selective cryolysis. We selected 4 subjects among the patients who maintained their body weight (within 5%) to minimize effects of losing weight. We practiced acupotomy with selective cryolysis therapy on 4 lesion of abdominal fat, 2 lesion of upper arm fat, 5 times for 2 month. All subjects had loss of abdominal circumference, and 1 subject had significantly loss of upper arm circumference. And there was no adverse effects. It shows that method of using acupotomy with selective cryolysis may be effective on localized fat.

Rhodamine B Hydrazide Revisited: Chemodosimetric Hg2+-selective Signaling Behavior in Aqueous Environments

  • Kim, Kyoung-Nam;Choi, Myung-Gil;Noh, Jae-Hyun;Ahn, Sang-Doo;Chang, Suk-Kyu
    • Bulletin of the Korean Chemical Society
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    • v.29 no.3
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    • pp.571-574
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    • 2008
  • The well-known Cu2+-selective chemodosimetric behavior of rhodamine B hydrazide was successfully switched to selectivity for Hg2+. The fluorescence signaling is remarkably selective toward Hg2+ ions compared to other common biologically and environmentally important metal ions, including Cu2+ ions. The detection limit was 0.2 mM in an acetate-buffered aqueous 10% methanol solution at pH 5. The OFF-ON type of signaling is due to the selective Hg2+-induced hydrolysis of the lactam ring of the hydrazide as has been reported for the standard Cu2+-signaling process of the same compound. A simple change in medium resulted in clear switching of selective signaling from Cu2+ to Hg2+, which extends the applicability of the easily accessible hydrazide derivative.

Deposition of Cermet Solar Selective Coatings for High Temperature Applications (고온용 서밋 태양선택흡수막의 증착)

  • Lee, Kil-Dong
    • Journal of the Korean Solar Energy Society
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    • v.26 no.1
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    • pp.57-64
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    • 2006
  • Cr-CrO cermet solar selective coatings with a double cermets layer film structure were prepared using a special direct current (dc) magnetron sputtering technology. The typical films structures from surface to bottom substrate were measured to be an $Al_2O_3$ anti-reflection layer on a double Cr-CrO cermet layer on an Al metal infrared reflection layer. Optical properties of optimized Cr-CrO cermet solar selective coating were absorptance (${\alpha}$) = 0.95 and emittance (${\varepsilon}$) = 0.10 ($100^{\circ}C$). Atomic force microscopy (AFM) image showed that Cr-CrO cermet film was very smooth and their grain size was also very small The results of thermal stability test showed that the Cr-CrO cermet solar selective coatings were stable for use at temperature of $400^{\circ}C$.

A robust detection scheme of OSTBCs with channel estimation errors over time-selective fading channels (실제적인 Time-Selective Fading Channels에서의 Orthogonal Space-Time Block Codes의 Detection Scheme)

  • Yu, Dong-Hun;Lee, Jae-Hong
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.17-18
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    • 2006
  • In this paper, we propose a robust detection scheme of OSTBCs with channel estimation errors over time-selective fading channels. Channel estimation errors are inevitable over time-selective fading channels and even small channel estimation errors dramatically degrade the performance of space-time block coding schemes. Therefore, it is desired to investigate the effect of channel estimation errors on the performance of the proposed detection scheme compared with the existing detection scheme. The proposed detection scheme minimizes noise enhancement and impact of channel estimation errors which occur in an existing detection scheme. It is shown by simulations that the proposed detection scheme performs better than the existing detection scheme over time-selective fading channels.

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