• Biomedical Science Letters
• /
• v.18 no.3
• /
• pp.193-200
• /
• 2012

We examined the effects of polyamines such as putrescine and cadaverine on the biosynthesis and secretion of insulin in the mouse pancreatic ${\beta}$-cell line, MIN-6. Basal insulin secretion (BIS) and glucose-stimulated insulin secretion (GSIS) from the MIN-6 cells were significantly increased by 20 min- or 24 h-treatment with micromolar concentrations of polyamines. To determine whether the enhancement was due to increase of insulin production by polyamines, we investigated the insulin mRNA and protein production. Both insulin mRNA and protein production were found to be not significantly affected by the polyamine treatment. Next, we examined the expression of several transcription factors (TFs) related to insulin synthesis and secretion in order to identify upstream events responsible for the promotion of insulin secretion of MIN6 cells by polyamines. Of the 6 TFs tested, MafA was induced by treatment of polyamines. MafA mRNA and protein expressions increased with treatment of polyamines. Overall results suggest that cadaverine and putrescine promote the insulin secretion process rather than the insulin biosynthesis from MIN6 cells. Also MafA may be involved in the enhanced insulin secretion process. Further studies are needed to elucidate the underlying mechanisms for promotion of insulin secretion by polyamines.

• Journal of the Ergonomics Society of Korea
• /
• v.18 no.2
• /
• pp.1-9
• /
• 1999

The objective of this study was to make comparison of the physical work capacities(PWCs) for three different types of tasks. For this purpose, an ergometer exercise, a treadmill exercise, and lifting activities with four different frequencies (2, 5, 8, 11 lifts/min) for the lifting range from floor to 76cm were considered. Oxygen consumption rates and heart rates were measured during the exercises and lifting activities. The PWC values for ergometer exercise test was $2562.71ml-O_2/min$ and the one for treadmill exercise was $2874.89ml-O_2/min$. The value of lifting PWC increased from $1774.07ml-O_2/min$ to $2296.76ml-O_2/min$ as the lifting frequency increased from 2 to 11 lifts/min. The ratio of the lifting PWCs to the ergometer PWC increased from 69.36% to 89.77% as the lifting frequency increased. To the treadmill PWC, the ratio increased from 62.21% to 85.24% as the lifting frequency increased. From this result, it appears that the PWCs based on the lifting tasks rather than PWCs by ergometer or treadmill exercise should be considered to determine the physiological criterion for safe weights for lifting tasks. Therefore, the physiological criteria of the NIOSH Guideline should be reexamined.

• Journal of Korea Soil Environment Society
• /
• v.5 no.3
• /
• pp.17-23
• /
• 2001

The adsorption and movement characteristics of herbicide pendimethalin was studied in three kinds of soil, sandy loam, silty clay and loam. The results of the batch test and columnexperimentweresummarizedasfollows. The shaking time reached to the adsorption equilibrium of pendimethalin in soils was 6 hours. The adsorption rates of pendimethalin for sandy loam, silty clay and loam were 59.6%, 77.3% and 64.0%, respectively. The adsorption isotherms with the Freundlich equation showed better consistency than that with the Langmuir one. The adsorption coefficients of pendimethalin for soils were 8.0. 16.1 and 9.5. respectively. When breakthrough point was 0.05Co, the breakthrough times reached for soils were 256 minutes, 810 minutes and 420 minutes. respectively.

• Korean Journal of Clinical Pharmacy
• /
• v.3 no.2
• /
• pp.147-155
• /
• 1993

The cardiac effects of PAF antagonist Ginkgolide B(BN 52051) have been investigated on the isolated perfused guinea pig hearts maintained at the constant hydrostatic perfusion pressure of 80 cm water. PDE(Phosphodiesterase) inhibitor KR-30289 was used as a positive control to see the positive inotropic effects on the perfused hearts. In this expriments, Ginkgolide $B(10^{-5}-SM)$ showed negative inotropic effects by decreasing of LVP, LVDP, LV dp/dt, HR and RPP(Rate Pressure Product). Ginkgolide B also decreased the number of extrasystole by $51.9\%(from\;23.75\pm9.22/min\;to\;11.43\pm435/min)$ induced by global ischemia and reperfusion. The rate, [-dp/dt]/[+dp/dt] increased in preischemia but decreased in postischemia. 1n the separated study the injection of 1ml of Ginkgolide B$(10^{-4M})$ on the isolated heart, increased coronary flow(CF) by $11.8\%(from\;7.5\pm7.65ml/min\;to\;8.5\pm0.29ml/min)$ and decreased the number of extrasystole by $47.6\%(from\;21\pm5.92/min\;to\;11\pm5.27/min)$. In conclusion, Ginkgolide B showed antiarrhythmic and protective effects by decreasing the number of extrasystole and by increasing the coronary flow, respectively.

• Fibers and Polymers
• /
• v.3 no.1
• /
• pp.18-23
• /
• 2002

The structure development and dynamic properties of fibers produced by high-speed spinning of P(EN-ET) random copolymers were investigated. The as-spun fibers were found to remain amorphous up to the spinning speed of 1500 m/min, and subsequent increases in speed resulted in the crystalline domains containing primarily $\alpha$ crystalline modification of PEN. The f modification was not found up to spinning speeds of 4500 m/min. On the other hand, annealing of constrained fibers spun at the 2100 m/min at 180,200, and 240^{\circ}C$ exhibited $\beta$-form crystalline structure, while the annealed fibers spun in 600-1500 m/min range exhibited dominantly $\alpha$-form. However $\beta$-form crystals disappeared above the spinning speed of 3000 m/min. With increasing spinning speeds from 600 to 4500 m/min, the storage modulus of as-spun fibers increased continuously and reached a value of about 10.4 spa at room temperature. The tan $\delta$curves showed the $\alpha$-relaxation peak at about 155-165^{\circ}C$, which is considered to correspond to the glass transition. The $\alpha$-relaxation peaks became smaller and broader, and shift to higher temperatures as the spinning speed increases, meaning that molecular mobility in the amorphous region is restricted by increased crystalline domain.

• Journal of the Korean Society for Precision Engineering
• /
• v.22 no.9 s.174
• /
• pp.130-136
• /
• 2005

This paper presents an optimal design and the performance evaluation of two-axis nano positioning stage with round notched flexure hinges. A flexure hinge mechanism with round notched flexure hinges is to guide the linear motions of a moving plate in the nano positioning stage. A Min-Max algorithm is applied to the design of the flexure hinge mechanism for nano positioning stage. In the design process, the structure of the flexure hinge mechanism is fixed, then the radius of a round hole and the width of two round holes are chosen as design variables, and finally the do sign variables are calculated by the Min-Max algorithm. The machined flexure hinge mechanism, stack type PZTs for actuation and capacitance type displacement sensors for position measurement are assembled into the nano positioning stage. The experimental results of the manufactured nano positioning stage show the first modal resonance frequency of 197 Hz, the operating range of 40 um, and the resolution of 3 nm.

• Journal of Nutrition and Health
• /
• v.28 no.7
• /
• pp.675-687
• /
• 1995

The purpose of this study were to analyze work patterns of clinical dietitians by time study, to investigate labor time used in each clinical dietetic activity, and to develop standardized indices of clinical dietetic staffing needs. Two general hospitals(A & B) in Seoul were selected for study. The results of this study can be summarized as follows. 1) For the A hospital, the percentage of clinical dietetic activities such as attending meeting, professional research, foodservicemanagement, clerical activity for the foodservice, administrative activity and delay were 17.5%, 1.3%, 14.5%, 23.4%, 21.3%, 4.6%, and 17.3% respectively, while 22.4% 3.5%, 23.7%, 10.9%, 15.8%, 4.2%, and 19.5% respectively for the B hospital. 2) For the A hospital, the percentage of direct patient care like outpatient nutrition education, group nutrition education, and patient meal planning were 69.5%, 10.5%, 7.6%, and 12.4% respectively while 78.9%, 7.3%, 8.9%, and 5.1% respectively for the B hospital. 3) Time spent for performing direct patient care such as basic care, intermediate care, and indepth care per patient were 28.0min, 73.1min, and 53.0 min respectively for the A hospital, while 45.3 min, 76.2 min, and 52.6 min respectively for the B hospital. 4) Full time clinical dietitian staffing needs were calculated for the three parts ; basic care, intermediate care, and in-depth care. For A hspital, the appropriate numbers of full time clinical dietitian were 3.5 persons in basic care, 3.6 persons in intermediate care, and 1.3 persons in in-depth care, while 6.1 persons, 6.3 persons, 3.2 persons respectively for B hospital.

• The Korean Journal of Food And Nutrition
• /
• v.11 no.5
• /
• pp.506-512
• /
• 1998

In order to replance systhetic colors by natural colors as food additive, properties of Gardenia yellow color and Gardenia blue color were compared with Food yellow No. 4 and Food blue No. 1. Color differeance between Food yellow No. 4 and Gardenia yellow color was 7.55. Thermal stability of Food yellow No. 4 was above 99%. On the other hand, in case of Gardenia yellow color, showed adove 90% of residual color units in 8$0^{\circ}C$$\times$30min and 10$0^{\circ}C$$\times$30min at pH 7.0 but 75% in 121$^{\circ}C$$\times$15min. Difference of light stability between Food yellow No. 4 and gardenia yellow color was about 18%. Addition of ascorbic acid was increased about 6% in light stability. Color difference between Food blue No. 2 and Gardenia blue color was 107. Thermal stability of Food blue No. 2 was above 99%. But Gardenia blue color showed 92% of residual color units in 8$0^{\circ}C$$\times$30min and 10$0^{\circ}C$$\times$30min at pH 7.0 but 90% in 121$^{\circ}C$$\times$15min. Difference of light stability between Food blue No. 4 and Gardenia blue color was about 8%. Addition of -tocopherol was increased about 4% in light stability of Gardenia blue color.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.38 no.2
• /
• pp.89-93
• /
• 2005

To manufacture the low-salt anchovy, Engraulis japonicus, sauces with $14\%$ and $17\%$ NaCl, anchovy sauce with $26\%$ NaCl was diluted with sterilized water and then heated at $60^{\circ}C$ for 10 min, 20 min, 30 min, and 40 min. The chemical and microbial changes of the heat-treated low-salt anchovy sauces stored at $25^{\circ}C$ were analyzed at different storage periods. Lactic acid and total nitrogen contents of $14\%$ and $17\%$ NaCl anchovy sauces decreased slightly during storage, but pH, VBN and amino nitrogen contents were almost constant. The amino nitrogen content of $17\%$ NaCl anchovy sauce was higher than that of $14\%$ NaCl anchovy sauce. Total viable cell and lactic acid bacteria were not detected in the anchovy sauce heated at $60^{\circ}C$ for more than 20 min and only proteolytic bacteria was determined less than 10 CFU/mL. The 17% NaCl anchovy sauce heated at $60^{\circ}C$ for 30 min was relatively good for the taste and odor by sensory evaluation.

• Journal of KIISE
• /
• v.43 no.3
• /
• pp.380-388
• /
• 2016

Graph clustering is widely used to analyze a graph and identify the properties of a graph by generating clusters consisting of similar vertices. Recently, large graph data is generated in diverse applications such as Social Network Services (SNS), the World Wide Web (WWW), and telephone networks. Therefore, the importance of graph clustering algorithms that process large graph data efficiently becomes increased. In this paper, we propose an effective clustering algorithm which generates clusters for large graph data efficiently. Our proposed algorithm effectively estimates similarities between clusters in graph data using Min-Hash and constructs clusters according to the computed similarities. In our experiment with real-world data sets, we demonstrate the efficiency of our proposed algorithm by comparing with existing algorithms.