• Journal of the Korean Society for Precision Engineering
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• v.13 no.5
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• pp.44-52
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• 1996

A procedure predicting warpage and post-deformation due to heat resistance test is presented. The procedure is applied to the injection molding processes of automotive plastic components, which are the door trim and the instrument pannel. The warpage of products is obtained from the residual stress after filling, packing and cooling process, and the post deformation due to the heat resistance test is calculated in the structural analysis of the product at the ejection temperature with the initial condition of residual stress, the boundary conditions and heat resistance conditions. The analyses give some useful guide lines in the design of automotive plastic parts which should satisfy heat resistance regulation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.12
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• pp.1183-1189
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• 2010

Shock-resistance test for a real equipment for a normal vessel is one of the difficult problem in many cases because of terrible cost and weight. An analysis technique to evaluate the shock resistance in a design stage is necessary, instead In this paper, the process to evaluate the shock resistance of a propulsion motor for naval vessels was presented based on German navy's BV043 regulation. The shock signal to impose the equipment under the test was first evaluated, and was then applied to the structural FE model of the equipment. From the transient FEA, the time history of von-Mises stress was obtained by the mode superposition method. The shock resistance was evaluated using the peak value of the von-Mises stress.

• Integrative Medicine Research
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• v.2 no.4
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• pp.131-138
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• 2013

The skeletal muscle in our body is a major site for bioenergetics and metabolism during exercise. Carbohydrates and fats are the primary nutrients that provide the necessary energy required to maintain cellular activities during exercise. The metabolic responses to exercise in glucose and lipid regulation depend on the intensity and duration of exercise. Because of the increasing prevalence of obesity, recent studies have focused on the cellular and molecular mechanisms of obesity-induced insulin resistance in skeletal muscle. Accumulation of intramyocellular lipid may lead to insulin resistance in skeletal muscle. In addition, lipid intermediates (e.g., fatty acyl-coenzyme A, diacylglycerol, and ceramide) impair insulin signaling in skeletal muscle. Recently, emerging evidence linking obesity-induced insulin resistance to excessive lipid oxidation, mitochondrial overload, and mitochondrial oxidative stress have been provided with mitochondrial function. This review will provide a brief comprehensive summary on exercise and skeletal muscle metabolism, and discuss the potential mechanisms of obesity-induced insulin resistance in skeletal muscle.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.134-134
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• 2012

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.112.2-112
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• 2003

Levels of blister rust infection (from Cronartium ribicola) varied in western white pine(Pinus monticola Dougl.) seedlings grown in two nurseries in northern Idaho. This observation suggested the potential importance of environmental components operating on the blister rust pathosystem. In an experiment designed to test the influence of environmental conditions at two nurseries, seedlings of a single genetic source were unintentionally held in cold storage for 6 months longer at one nursery than at the other. Subsequently, these seedlings, which had been growing under nursery conditions for 7 months or 1 month, were inoculated with blister rust spores on September 9th, 1999. Infection efficiency measured on the seedlings with only 1 month of growth was 70X greater than on the seedlings that had 7 months for their new growth to mature. Results from this nursery test and infection levels of northern Idaho resistant selections in mild climates suggest that expression of genes related to rust resistance in western white pine can be manipulated by regulation of phonology. If so, several new molecular tools may be employed to enhance our understanding of environmental regulation of genes for blister rust resistance.

• The Korea Journal of Herbology
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• v.31 no.1
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• pp.1-5
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• 2016

Objectives : The purpose of this study was to investigate inhibitory effects of steamed Polygonatum odoratum extract (POE) on insulin resistance in rat skeletal muscle cells, L6 cells.Methods : Polygonatum odoratum (P. odoratum) extract was extracted with ethyl acetate. Activity of α-glucosidase in POE was measured for blood glucose regulation. MTT assay was examined for cell toxicity. Western blot analysis for measurement of adiponectine, peroxisome proliferator-activated receptorγ (PPARγ), insulin receptor substrate (IRS), glucose transporter 4 (Glut-4) and phosphorylation of serine/threonine-specific protein kinase (Akt) expressions were performed. Akt signaling pathway were analyzed with LY294002, which is a specific PI3K/Akt inhibitor.Results : The results revealed that POE inhibited α-glucosidase activity. Treatment of POE in L6 cells inhibited the differentiation of L6 cells compared to those of vehicl control. Additionally, protein expressions of adiponectine, PPARγ, IRS and Glut-4 were significantly regulated compared to those of vehicle control (p < 0.05), respectively. Futhermore, phosphorylation of Akt was increased in L6 cells treated with POE compared to that of vehicle control (p < 0.05). pAkt expression was significantly accentuated with Akt inhibitor (LY294002).Conclusions : These results suggest that POE may have potential as a natural agent for prevention/improvement of diabetes, especially, regulation of blood glucose. Therefore, further additional study should be conducted to elucidate in depth the pharmaceutical efficacy of these.

• Structural Engineering and Mechanics
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• v.58 no.1
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• pp.39-58
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• 2016

Since the publication of ACI 318-02, the concrete capacity design (CCD) method has been used to determine the resistance of unreinforced concrete anchors. The regulation of steel-reinforced anchors was proposed in ACI 318-08. Until ACI 318-08, the shear resistance of concrete breakout for an unreinforced anchor during an earthquake was reduced to 75% of the static shear strength, but this reduction has been eliminated since ACI 318-11. In addition, the resistance of a hairpin-reinforced anchor was calculated using only the strength of the steel, and a regulation on the dynamic strength was not given for reinforced anchors. In this study, shaking table tests were performed to evaluate the dynamic shear strength of unreinforced and hairpin-reinforced cast-in-place (CIP) anchors during earthquakes. The anchors used in this study were 30 mm in diameter, with edge distances of 150 mm and embedment depths of 240 mm. The diameter of the hairpin steel was 10 mm. Shaking table tests were carried out on two specimens using the artificial earthquake, based on the United States Nuclear Regulatory Commission (US NRC)'s Regulatory Guide 1.60, and the Northridge earthquake. The experimental results were compared to the current ACI 318 and ETAG 001 design codes.

• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.645-650
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• 2020

The mechanism of anti-aging of fermented jujube (Zizyphus jujuba fruits (ZJF)) was investigated using transgenic daf-16 and mev-1 strains of C. elegans. Jujube extracts fermented for 7 days (F7-ZJF) and 14 days (F14-ZJF) with Laetiporus sulphureus were treated to a NGM agar plate with 10-15 transgenic daf-16 and mev-1 strains of the synchronized age. There was no difference of lifespan between the drug-treated group (7-day fermented ex. (F7-zjf-200 ㎍/mL), 14-day fermented ex. (F14-zjf-200 ㎍/mL)) and the non-treatment group in both daf-16 and mev-1 strains. In the thermal stress experiment, F7-zjf-200 ㎍/mL showed a significant (t = 4.017) activity in thermal stress resistance with a 12% higher survival rate than the control group. In the survival test in H2O2, F7-zjf-200 ㎍/mL and F14-zjf-100 ㎍/mL have significant activity in oxidative stress resistance compared to the control group. This study indicates that life span expand of N2 strain of the jujube extract is related to the regulation of daf-16 and inhibition of mev-1 signal in C. elegans.

• International Journal of Stem Cells
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• v.16 no.2
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• pp.156-167
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• 2023

Background and Objectives: Cellular reprogramming in regenerative medicine holds great promise for treating patients with neurological disorders. In this regard, small molecule-mediated cellular conversion has attracted special attention because of its ease of reproducibility, applicability, and fewer safety concerns. However, currently available protocols for the direct conversion of somatic cells to neurons are limited in clinical application due of their complex nature, lengthy process, and low conversion efficiency. Methods and Results: Here, we report a new protocol involving chemical-based direct conversion of human fibroblasts (HF) to matured neuron-like cells with a short duration and high conversion efficiency using temporal and strategic dual epigenetic regulation. In this protocol, epigenetic modulation by inhibition of histone deacetylase and bromodomain enabled to overcome "recalcitrant" nature of adult fibroblasts and shorten the duration of neuronal reprogramming. We further observed that an extended epigenetic regulation is necessary to maintain the induced neuronal program to generate a homogenous population of neuron-like cells. Conclusions: Therefore, our study provides a new protocol to produce neurons-like cells and highlights the need of proper epigenetic resetting to establish and maintain neuronal program in HF.

• BMB Reports
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• v.33 no.1
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• pp.1-36
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• 2000

Acetohydroxyacid synthase (EC 4.1.3.18) catalyses the first reaction in the pathway for synthesis of the branched-chain amino acids. The enzyme is inhibited by several commercial herbicides and has been subjected to detailed study over the last 20 to 30 years. Here we review the progress that has been made in understanding its structure, regulation, mechanism, and inhibition.