• Title/Summary/Keyword: unitary group

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HYERS-ULAM-RASSIAS STABILITY OF ISOMORPHISMS IN C*-ALGEBRAS

  • Park, Choonkil
    • Journal of the Chungcheong Mathematical Society
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    • v.19 no.2
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    • pp.159-175
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    • 2006
  • This paper is a survey on the Hyers-Ulam-Rassias stability of the Jensen functional equation in $C^*$-algebras. The concept of Hyers-Ulam-Rassias stability originated from the Th.M. Rassias' stability theorem that appeared in his paper: On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc. 72 (1978), 297-300. Its content is divided into the following sections: 1. Introduction and preliminaries. 2. Approximate isomorphisms in $C^*$-algebras. 3. Approximate isomorphisms in Lie $C^*$-algebras. 4. Approximate isomorphisms in $JC^*$-algebras. 5. Stability of derivations on a $C^*$-algebra. 6. Stability of derivations on a Lie $C^*$-algebra. 7. Stability of derivations on a $JC^*$-algebra.

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Intrinsic Gating in Inward Rectifier Potassium Channels (Kir2.1) with Low Polyamine Affinity Generated by Site Directed Mutagenesis

  • So, I.;Ashmole, I.;Soh, H.;Park, C.S.;Spencer, P.J.;Leyland, M.;Stanfield, P.R.
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.3
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    • pp.131-142
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    • 2003
  • We have studied mutant forms of Kir2.1 in which an aspartate residue (D172), important for gating by intracellular polyamines, is replaced by one of three basic residues (Arg, Lys or His). Such channels are highly selective for $K^+$, but show inward rectification that is a shallow function of voltage compared with that found in wild type. This inward rectification occurs with a reduced affinity for spermine and persists in the absence of polyamines. Though the unitary current-voltage relation shows some inward rectification, it is insufficient to account for that seen under whole cell recording. Channels open and shut under single channel recording, and changes of $P_{open}$ appear to generate inward rectification. In D172H, the reduction in affinity for spermine is greater when His is protonated at low $pH_i$. The effective valency for spermine is reduced from $3.09{\pm}0.07$ in wild type to $1.95{\pm}0.09$ in D172H at $pH_i$ 6.3. In the presence of dual mutants of Kir2.1, where E224 is also replaced, spermine affinity becomes undetectable. However, channels still show inward rectification and open and shut under hyper- and depolarisation, respectively. We suggest that Kir2.1 channel are able to undergo conformation changes; these changes may be important physiologically in generating inward rectification, the normal parameters of which are set by the binding of polyamines such as spermine.

Reasoning Models in Physics Learning of Scientifically Gifted Students (과학영재의 물리개념 이해에 관한 사고모형)

  • Lee, Young-Mee;Kim, Sung-Won
    • Journal of The Korean Association For Science Education
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    • v.28 no.8
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    • pp.796-813
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    • 2008
  • A good understanding of how gifted science students understand physics is important to developing and delivering effective curriculum for gifted science students. This dissertation reports on a systematic investigation of gifted science students' reasoning model in learning physics. An analysis of videotaped class work, written work and interviews indicate that I will discuss the framework to characterize student reasoning. There are three main groups of students. The first group of gifted science students holds several different understandings of a single concept and apply them inconsistently to the tasks related to that concept. Most of these students hold the Aristotelian Model about Newton's second law. In this case, I define this reasoning model as the manifold model. The second group of gifted science students hold a unitary understanding of a single concept and apply it consistently to several tasks. Most of these students hold a Newtonian Model about Newton's second law. In this case, I define this reasoning model as the coherence model. Finally, some gifted science students have a manifold model with several different perceptions of a single concept and apply them inconsistently to tasks related to the concept. Most of these students hold the Aristotelian Model about Newton's second law. In this case, I define this reasoning model as the coherence model.

The alterations of $Ca^{2+}$-activated $K^+$ channels in coronary artery during cardiac hypertrophy

  • Kim, Nari;Lee, Sang-Kyeong;Chung, Joon-Yong;Seog, Dae-Hyun;Kim, Euiyong;Jin Han
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.23-23
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    • 2003
  • It has been suggested that the impairment of smooth muscle cell (SMC) function by alterations in the $Ca^{2+}$-activated $K^{+}$ ( $K_{Ca}$ ) channels accounts for the reduction in coronary reserve during left ventricular hypertrophy (LVH). However, this hypothesis has not been fully investigated. The main goal of this study was to assess whether the properties of $K_{Ca}$ channels in coronary SMCs were altered during LVH. New Zealand white rabbits (0.8-1.0 kg) and Sprague-Dawley rats (300-400 g) were randomly selected to receive either an injection of isoproterenol (300 $\mu\textrm{g}$/kg body weight) or an equal volume of 0.9% saline (1 mL/kg body weight). The animals developed LVH 10 days after injection. In patch-clamp experiments, the unitary current amplitude and open probability for the $K_{Ca}$ channels were significantly reduced in LVH patches compared with control patches. The concentration-response curve of the $K_{Ca}$ channel to [C $a^{2+}$]$_{i}$ was shifted to the right. Inhibition of the $K_{Ca}$ channels with TEA was more pronounced in LVH cells than in the control cells. The whole-cell currents of $K_{Ca}$ channels were reduced during LVH. Western blot analysis indicated no differences in $K_{Ca}$ channel expression between the control and LVH coronary SM membranes. In contraction experiments, the effect of a high $K^{+}$concentration on the resting tension of the LVH coronary artery was greater than on that of the control. The effect of TEA on the resting tension of the LVH coronary artery was reduced as compared with the effect on the control. Our findings imply a novel mechanism for reduced coronary reserve during LVH.ing LVH.

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The Change of Lower-limb Muscle Activity according to Gait speed when Normal and Assistive Gait of older (노인의 정상 보행과 보행보조기를 사용한 보행 시 속도변화에 따른 하지 근 활성도 변화)

  • Kim, Byung-Kon;Kim, Tae-Ho
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.14 no.2
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    • pp.60-67
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    • 2008
  • Purpose : The purpose of this study is to investigate that the change of lower-limb muscle activity when normal gait and assistive gait of older. Methods : The selected subjects of this study were 11 older who be in good physical health and have not problem to gait and over 60 age to analyze the muscle activity. This study has been conducted to analyze the muscle activity of normal gait and assistive gait in unitary status without any contrast group. We have them gait condition of a gradient of 0% and velocity of 1km/h, 2km/h, 3km/h electrode were attached to the motor point of Rectus femoris, Hamstrings, Tibialis anterior, Calf muscle. When normal gait and assistive gait performs, there are meaningful differences that the muscle activity takes a small drop in Rectus femoris by 9.17% at 1km/h, 9.79% at 2km/h, 13.80% at 3km/h, hamstring by 14.78% at 1km/h, 17.82% at 2km/h, 17.26% at 3km/h, Tibialis anterior by 24.38% at 1km/h, 23.85% at 2km/h, 33.52% at 3km/h, Calf muscle by 13.68% at 1km/h, 16.70% at 2km/h, 18.37% at 3km/h(p<0.05). Results : They show the significant difference in statistical figure. We've received the significant through the comparison between normal gait and assistive gait. These results will be utilized for the preliminary date in the future.

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Korea's Designation of Living Happiness Sphere in the Local Area from the Perspective of New Institutionalism (지역행복생활권 획정에 대한 신제도주의적 접근)

  • Oh, Seong-Ik
    • Journal of the Economic Geographical Society of Korea
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    • v.18 no.3
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    • pp.366-380
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    • 2015
  • Park Geun-hye Administration has been leading HOPE Area(Living Happiness Sphere) policy as a part of strategy for the regional development. Recent study on HOPE Area policy mainly focuses on how to enhance cooperation among local governments or how to activate the HOPE area. However, as far as I found, the research on how HOPE area guideline as an institution is made and how HOPE area, the effect of the institution, is demarcated has not well been conducted. With based on these issues, this article aims to identify and examine the process of the HOPE area guideline-making and the designation of the HOPE area. For this purpose, new institutionalism is utilized for the analysis. The guideline was made through competition and compromise among a few parties concerned rather than a decision by unitary elite group, and the final outcome of the process reflected the balanced development strategy more than the growth pole development strategy. There was a tendency that the local governments try to make many HOPE areas by overlapping the HOPE areas, which are the outcomes of the bottom-up approach. In Seoul metropolitan area, a new type of HOPE area was introduced one year later than the other local regions.

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