• The Korean Journal of Physiology and Pharmacology
• /
• v.6 no.5
• /
• pp.255-260
• /
• 2002

The effects of intracellular and extracellular pH on the inwardly rectifying $K^+$ (IRK) channel of the bovine aortic endothelial cells (BAECs) were examined using whole-cell patch-clamp technique. The IRK current, efficiently blocked by $Ba^{2+}\;(200{\mu}M),$ is the most prominent membrane current in BAECs, which mainly determines the resting membrane potential. The expression of Kir2.1 was observed in BAECs using reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Intracellular alkalinization, elicited by the extracellular substitution of NaCl with $NH_4Cl$ (30 mM), significantly augmented the amplitude of IRK current. On the contrary, the amplitude of IRK current was attenuated by the Na-acetate (30 mM)-induced intracellular acidification. The changes in extracellular pH also closely modulated the amplitude of IRK current, which was decreased to $40.2{\pm}1.3%$ of control upon switching the extracellular pH to 4.0 from 7.4. The extracellular pH value for half-maximal inhibition (pK) of IRK current was 5.11. These results demonstrate that the activity of IRK channel in BAECs, probably Kir2.1, was suppressed by proton at both sides of plasma membrane.

• Journal of Mechanical Science and Technology
• /
• v.19 no.spc1
• /
• pp.388-394
• /
• 2005

Recently, the authors have developed a method for real-time dynamics of multibody systems, which combines a semi-recursive formulation to derive the equations of motion in dependent relative coordinates, along with an augmented Lagrangian technique to impose the loop closure conditions. The following numerical integration procedures, which can be grouped into the so-called structural integrators, were tested : trapezoidal rule, Newmark dissipative schemes, HHT rule, and the Generalized-${\alpha}$ family. It was shown that, for large multi body systems, Newmark dissipative was the best election since, provided that the adequate parameters were chosen, excellent behavior was achieved in terms of efficiency and robustness with acceptable levels of accuracy. In the present paper, the performance of the described method in combination with another group of integrators, the Implicit Runge-Kutta family (IRK), is analyzed. The purpose is to clarify which kind of IRK algorithms can be more suitable for real-time applications, and to see whether they can be competitive with the already tested structural family of integrators. The final objective of the work is to provide some practical criteria for those interested in achieving real-time performance for large and complex multibody systems.

• Journal of applied mathematics & informatics
• /
• v.15 no.1_2
• /
• pp.1-28
• /
• 2004

We first apply a first order splitting to a semilinear reaction-diffusion equation and then discretize the resulting system by an $H^1$-Galerkin mixed finite element method in space. This semidiscrete method yields a system of differential algebraic equations (DAEs) of index one. A priori error estimates for semidiscrete scheme are derived for both differ-ential as well as algebraic components. For fully discretization, an implicit Runge-Kutta (IRK) methods is applied to the temporal direction and the error estimates are discussed for both components. Finally, we conclude the paper with a numerical example.

• Korean Journal of Child Studies
• /
• v.13 no.2
• /
• pp.19-31
• /
• 1992

The purpose of this study was (1) to construct 'easy-to-read' books and (2) to investigate the effect of 'easy-to-read' books on young children's independent reading, the subjects were twenty six three and four-year-old children who attended a Saemaul murery school in Irk, chullapuk-do. The subjects were randomly assigned to and of two storybook reading conditions: in the first condition. subjects were encouraged to read traditional storybooks and in the second condition, subjects were encouraged to read 'easy-to-read' books. The paired t-test and the Student's t-test were employed to analyze the data. The results showed that subjects in both groups attempted to read more frequently in the post-test than in the pre-test. Subject in the 'easy-to-read' condition attempted to read more frequently on the post test than subjects in the traditional book condition.

• International journal of advanced smart convergence
• /
• v.2 no.1
• /
• pp.18-20
• /
• 2013

The significance, is to introduce a novel way to employ the improved Runge-Kutta fifth order five stage method, here after called as Modified IRK(5,5) method, for system of second order robot arm problem and variations in angles at the joints in which parameters governing with two degrees of freedom which requires lesser number of function evaluations per time step as compared to the existing ones, in order to save time and spaceAn ultimate aim of this present paper is to solve application problem such as robot arm and initial value problems by applying Runge-Kutta fifth order five stage numerical techniques. The calculated output for robot arm coincides with exact solution which is found to be better, suitable and feasible for solving real time problems.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.24 no.7
• /
• pp.1004-1014
• /
• 2000

The purpose of this study was to develop a well-fitting bodice basic pattern for high school irk. Two bodice patterns were first made based on the most recent existing drafting methods and sensory evaluation was done on the patterns by the present researchers Two high school girls possessing standard physical condition tried and evaluated the functionality of the garments made by the two bodice patterns. Based on the results of the evaluation, a new bodice basic pattern was developed. The new bodice basic pattern was drafted by long measurement method. The dimensions of new bodice basic pattern were as follows. Bust circumference=B/2+4cm, Arms hole depth=C.B/2+1.5cm, Back width=B/6+4cm, Front width=B/6+3cm, Back neck width=B/12+0.5cm, Back neck depth=Back neck width/3cm, Front neck width=B/12cm, Front neck depth=B/12+0.5cm. The sensory and functional evaluations were also conducted for the new bodice basic pattern and the two patterns drafted by the existing methods. The new bodice basic pattern showed better fit both visually and functionally than the existing patterns. SPSS package including means, standard deviation and one-sample T-test were used for data analysis.

• Molecules and Cells
• /
• v.40 no.9
• /
• pp.685-695
• /
• 2017

Obesity and the metabolic disorders that constitute metabolic syndrome are a primary cause of morbidity and mortality in the world. Nonetheless, the changes in the proteins and the underlying molecular pathways involved in the relevant pathogenesis are poorly understood. In this study a proteomic analysis of the visceral adipose tissue isolated from metabolically healthy and unhealthy obese patients was used to identify presence of altered pathway(s) leading to metabolic dysfunction. Samples were obtained from 18 obese patients undergoing bariatric surgery and were subdivided into two groups based on the presence or absence of comorbidities as defined by the International Diabetes Federation. Two dimensional difference in-gel electrophoresis coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was carried out. A total of 28 proteins were identified with a statistically significant difference in abundance and a 1.5-fold change (ANOVA, $p{\leq}0.05$) between the groups. 11 proteins showed increased abundance while 17 proteins were decreased in the metabolically unhealthy obese compared to the healthy obese. The differentially expressed proteins belonged broadly to three functional categories: (i) protein and lipid metabolism (ii) cytoskeleton and (iii) regulation of other metabolic processes. Network analysis by Ingenuity pathway analysis identified the $NF{\kappa}B$, IRK/MAPK and PKC as the nodes with the highest connections within the connectivity map. The top network pathway identified in our protein data set related to cellular movement, hematological system development and function, and immune cell trafficking. The VAT proteome between the two groups differed substantially between the groups which could potentially be the reason for metabolic dysfunction.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.10A
• /
• pp.962-968
• /
• 2002

Reliable high-speed data communications over insufficient channel bandwidth is one of the major challenges of harsh wireless environments that push the achievable spectral efficiency far below its theoretical limits. A Quadrature amplitude modulation (QAM) scheme is a userful modulation technique for achieving high data rate transmission without increasing the bandwidth of wireless communication systems. The exact general bit error rate (BER) expression of arbitrary rectangular quadrature amplitude modulation has not yet been derived. In this paper, a generalized closed-form expression for the BER performance of rectangular QAM with Gray code bit mapping is derived and analyzed in the presence of additive white Gaussian noise (AWGN) channel. First we analyze the BER performance of an I-ary PAM scheme. Regular patterns in the k-th bit error probability are observed while developing the EBR expression. From these patterns we provide the exact and general closed-from EBR expression of an I-ary PAM. Then we present a general closed-from expression for BER of an arbitrary IXJ rectangular QAM by considering that this signaling format consists of two PAM scheme, i.e., I-ary and J-ary PAM. A simple approximate BER expression for rectangular QAM is given as well.