https://pubs.kist.re.kr/handle/123456789/75355 2026-04-21T23:16:47Z https://pubs.kist.re.kr/handle/201004/153426 Title: Cytoprotective effect of Scutellaria baicalensis in CA1 hippocampal neurons of rats after global cerebral ischemia Authors: Kim, YO; Leem, K; Park, J; Lee, P; Ahn, DK; Lee, BC; Park, Ho Koon; Suk, K; Kim, SY; Kim, H Abstract: Based on the use of Scutellaria baicalensis for the treatment of stroke in traditional Oriental medicine, the current study was carried out to evaluate neuroprotective effects of S. baicalensis after transient global ischemia using rat 4-vessel occlusion model. Methanol extracts from the dried roots of S. baicalensis (0.1-10 mg/kg) administered intra-peritoneally significantly protected CAI neurons against 10 min transient forebrain ischemia as demonstrated by measuring the density of neuronal cells stained with Cresyl violet. Methanol extract of S. baicalensis inhibited microglial tumor necrosis factor-alpha (TNF-alpha) and nitric oxide production, and protected PC12 cells from hydrogen peroxide-induced toxicity in vitro. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved. 2001-10-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/140834 Title: Near minimum-time direct voltage control algorithms for wheeled mobile robots with current and voltage constraints Authors: Choi, JS; Kim, BK Abstract: Near minimum-time direct voltage control (DVC) algorithms synthesizing path-planning and path-following are proposed for wheeled mobile robots (WMRs) satisfying (i) initial and final postures and velocities as well as (ii) voltage and current constraints. To overcome nonholonomic and nonlinear properties of WMRs, we divide our control algorithm for cornering motion into three sections: TSD (Translational Section of Deceleration), RS (Rotational Section), and TSA (Translational Section of Acceleration). We developed off-line DVC algorithms using the quadratic problem with the object function minimizing the total time, where voltages to the motors are controlled directly without velocity/torque-servo modules. while satisfying the current constraints. Two methods of searching for the two control parameters (number of steps for RS M-R and velocity constraint in RS beta) were considered: The one is composed of one simple 1-dimensional search for beta, and the other is composed of two 1-dimensional searches for M-R and beta which has better performance. Performances of the proposed control algorithms are validated via various simulations. 2001-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/140833 Title: Subcellular redistribution of protein kinase C isozymes is associated with rat liver cirrhotic changes induced by carbon tetrachloride or thioacetamide Authors: Jeong, DH; Lee, SJ; Lee, JH; Bae, IH; Jeong, KS; Jang, JJ; Lim, IK; Kim, MR; Lee, MJ; Lee, YS Abstract: Background and Aims: Protein kinase C (PKC) plays a key role in the alteration of signal transduction in the liver, which may contribute to the development of liver cirrhosis. The aim of the present study was to examine the subcellular redistribution of PKC isozymes in rat liver cirrhosis, which is induced by two different cirrhotic chemical agents, carbon tetrachloride (CCl4) and thioacetamide (TAA). Methods and Results: Thioacetamide and CCl4 were administered to rats for 8 and 30 weeks, respectively before rats were killed and autopsies performed at 9, 20 and 30 weeks later. The TAA induced a fibrotic pattern in the liver that differed from that produced by CCl4, notably in the formation of fibrous connective tissue and the proliferation of bile ductule cells. Cholangiofibrosis and clear-cell foci were also observed in TAA-treated rats at 30 weeks. Histological examination revealed that severe cirrhotic changes were present 9 weeks after the commencement of CCl4 treatment and 30 weeks after TTA treatment. Discussion: When the subcellular redistribution of PKC isozymes (PKC alpha, -beta1, -delta, and -epsilon) was examined, all the PKC isozymes in CCl4-treated rats were found to be translocated to the membrane fraction, which may mean PKC activation, and then downregulated by proteolytic degradation after 9 weeks of treatment, which coincided with peak cirrhotic changes. All rats treated with CCl4 recovered to the control level after 20 weeks of treatment, In the case of TAA-treated rats, PKC isozymes were translocated to the particulate fraction of the liver after 9 weeks of treatment and this persisted in most of the rats for the duration of the experiment. Conclusions: From these results, it would appear that PKC translocation preceded morphologic changes, and that an altered subcellular distribution of the PKC isozyme may be associated with the response to liver damage and carcinogenesis. (C) 2001 Blackwell Science Asia Pty Ltd. 2001-01-01T00:00:00Z https://pubs.kist.re.kr/handle/201004/140832 Title: Diffraction pattern by an empty rectangular cylinder in a dielectric Authors: Lee, TK; Kim, SY; Ra, JW Abstract: The capability of frequency-swept cross-borehole radar to detect an empty rectangular cylinder embedded in a. dielectric medium is simulated numerically by employing the boundary element method. The frequency loci providing the strongest double dips in the received signal pattern are plotted as functions of the observation distance and the cross-sectional width. It is found that, regardless of the shape of thf rectangular cross-section, the strongest double dips become double nulls in the near-field region. 2001-01-01T00:00:00Z