• Title/Summary/Keyword: concentration effect

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Antibacterial and Antifungal Effect by Artemisia lavandulaefolia Essential Oil (참쑥 정유의 항세균 및 항진균 효과)

  • 한규용
    • The Korean Journal of Food And Nutrition
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    • v.12 no.6
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    • pp.559-563
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    • 1999
  • Essential oil of Artemisia lavandulaefolia the chrysanthemum family plant used in the chinese medicine was extracted and antibacterial and antifungal activity with many kinds of the pathogenic bacterium and fungi was experimented by it. Ataphylococcus epidermidis and Streptococcus aureus gram positive bacterium at the concentration of 200ppm and Streptococcus mutans at the concentration of 1,000ppm showed the growth injibition effect of the cell. These showed statistically significant difference(p<0.05) Zymomonas mobilis Entrecoccus faecalis gram negative bacterium at the concentration of 200ppm and Pseudomonas putida at the concentration of 400ppm showedd the growth inhibition effect of the cell)p<0.05) V. Parahaemolyticus at the concentration of 800ppm and Pseudomonas aeruginosa at the concentration of 1,000ppm showed the growth inhibition effect of the cell(p<0.05) Candida albicans and Cryptococcus neoformans yeast-type fungi showed the gorwth inhibition effect of the cell at the concentration of 200ppm(p<0.05) Altenaria mali Aspergillus nidulans and Fusarium oxysporum filamentous fungi took the growth inhibition effect of the cell at the concentration of 600ppm, 400ppm, and 100ppm. respectively.

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Effects of Heavy Metals on Growth and Seed Germination of Arabidopsis thaliana (중금속이 애기장대의 생장과 종자발아에 미치는 영향)

  • 박영숙;박종범
    • Journal of Environmental Science International
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    • v.11 no.4
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    • pp.319-325
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    • 2002
  • This experiment was carried out to investigate the effects of heavy metals (copper, cadmium, lead and chrome) on the growth of plant and seed germination of Arabidopsis thaliana treated with various concentrations of heavy metals. Cadmium and chrome among the 4 heavy metals had no effect on the growth of stem even in the concentration fifty times higher than the official standard concentration of pollutant exhaust notified by the Ministry of Environment. The official standard concentration of cadmium, however, stimulated the growth of stem in general, increasing leaf size and surface area, although it had no effect on the length of stem. But the growth of stem was decreased about 18% in the official standard concentration of pollutant exhaust of lead and copper. There was no growth of root in the concentration of lead and copper ten times higher than the official standard concentration. Cadmium and chrome had no effect on the seed germination, but lead and copper decreased the rate of seed germination. Seeds were not germinated in the concentration of copper ten times higher than the official standard concentration and in the concentration of lead fifty times higher than the official standard concentration. From this research three peculiar results were obtained. Chrome in the soil did not have much effect on the plant growth and seed germination of Arabidopsis thaliana. Cadmium stimulated the stem growth in an optimum concentration. But lead and copper reduced the plant growth and seed germination even in a small concentration, especially copper had the worse effect.

Development of Target-Controlled Infusion system in Plasma Concentration. PART2: Design and Evaluation (혈중 목표 농도 자동 조절기(TCI) 개발 PART2: 시스템 구현 및 평가)

  • 안재목
    • Journal of Biomedical Engineering Research
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    • v.24 no.1
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    • pp.45-53
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    • 2003
  • Based on the 4-compartmental pharmacokinetic model developed in PART1, target-controlled infusion(TCI) pump system was designed and evaluated. The TCI system consists of digital board including microcontroller and digital signal process(DSP), analog board, motor-driven actuator, user friendly interface, power management and controller. It provides two modes according to the drugs: plasma target concentration and effect target concentration. Anaesthetist controls the depth of anaesthesia for patients by adjusting the required concentration to maintain both plasma and effect site in drug concentration. The data estimated in DSP include infusion rate, initial load dose, and rotation number of motor encoder. During TCI operation, plasma concentration. effect site concentration, awaken concentration, context-sensitive decrement time and system error information are displayed in real time. Li-ion battery guarantees above 2 hours without power line failure. For high reliability of the system, two microprocessors were used to perform independent functions for both pharmacokinetic algorithm and motor control strategy.

Effects of Hwang Keum Jag Yag Tang Water Extract on the Plasma Cortisol Concentration and in the Rabbit and on the Analgesic Effect in the Mouse (黃芩芍藥湯 煎湯液이 血漿Cortisol 및 鎭痛에 미치는 影響)

  • Oh, Chun-Keun;Hwang, Choong-Yeon;Lee, Ki-Nam
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.3 no.1
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    • pp.41-57
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    • 1990
  • In order to investigate the effects of Hwang Keum Jag Yag Tang (HJT) water extract on the plasma cortisol concentration in the rabbit and on the analgesic effect in the mouse were administered. The results were summarized as follow: 1. Intravenous administration of HJT water extract at the dose of 0.2ml/kg remarkably increased plasma cortisol concentration after two hour. 2. Intravenous administration of HJT water extract at the dose of 0.4ml/kg significantly increased plasma cortisol concentration after one hour. 3. Intravenous administration of HJT water extract at the dose of 0.2ml/kg, all the experimental period, significantly increased plasma sodium concentration. 4. Intravenous administration of HJT water extract at the dose of 0.4m1/kg significantly decreased plasma potassium concentration. 5. Intravenous administration of HJT water extract at the dose of 0.2ml/kg and 0.4ml/kg, all the experimental period, significantly decreased plasma calcium concentration. 6. The analgesic effect of HJT water extract showed inhibitory effect more than at 0.1ml/20g. According to the results, Hwang Keum Jag Yag Tang water extract remarkably increased plasma cortisol concentration and showed analgesic effect.

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Effect of Saryuktangkamibang on Streptozotocin-induced Diabetic Rat (사육탕가미방(四六湯加味方)이 streptozotocin으로 유발(誘發)된 백서(白鼠)의 실험적(實驗的) 탕뇨(糖尿)에 미치는 영향)

  • Oh, Young-Taek;Kim, Dong-Woo
    • Herbal Formula Science
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    • v.14 no.2
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    • pp.57-66
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    • 2006
  • Objectives : The objective of this study is to observe the effect of Saryuktangkamibang, Saryuktang with Liriopis Tuber, Lycii Fructus, Schizandrae Fructus, and Bombyx Batryticatus, on the experimental diabetes. Methods : In order to induce diabetes experimentally, injected streptozotocin to the vein in the tail of rats and then treated oral administration of Saryuktangkamibang water extracts. In the measurement of the variation levels of glucose, ALP, creatinine, and BUN concentration for each concentration levels for serum (0.2g/100g, 0.4g/l00g, 0.6g/100g), concentration level of glucose significantly decreased in 0.4g/l00g concentration level of Saryuktangkamibang. With this 0.4g/l00g concentration level of Saryuktangkamibang, the following conclusion was derived from the measurement of the serum levels of glucose. ALP, AST, ALT, creatinine, and BUN concentration for the injection of each 4th, 11th, and 18th day. Results : 1. In the measurement for each concentrations, the glucose concentration level in the serum significantly decreased on the 9th day in the Saryuktangkamibang-dosed group. 2. The creatinine and BUN concentration level in the serum significantly decreased on the 9th day in the Saryuktangkamibang-dosed group to which 0.6g/100g injected. 3. In the measurement for each dosage dates, the glucose concentration level in the serum significantly decreased on the 11th day in the Saryuktangkamibang-dosed group to which 0.6g/100g injected. 4. The AST concentration level in the serum significantly decreased on the 11th day in the Saryuktangkamibang-dosed group. Conclusion : Saryuktangkamibang, Saruktang with Liriopis Tuber, Lycii Fructus, Schizandrae Fructus, and Bombyx Batryticatus, has an effect of hypoglycemia, with no hepato-renal dysfunction. For the experimental results above, in that nephrotoxicity significantly decreased on the 0.6g/100g concentration, another research such as study for effect in other ranges and study for effect of dosage term except the concentration range of this study is necessary. Also dosage of appropriate concentration of Saryuktangkamibang is thought to provide valuable aid to cure on diabetes.

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A Study on Stress Concentration Alleviation at Pipe Connections (관로 연결부의 응력집중저감기법연구)

  • Chung, So-Young;Han, Taek-Hee;Han, Keum-Ho;Kang, Young-Jong
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.289-292
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    • 2007
  • Stress concentration have a effect on commission of structures and sometimes it cause the fracture of structures. Stress concentration is appeared where have a sudden section change like pipe connections. So stress concentration is a potent influence at pipe connentions. This paper make a study of pipe connections to alleviate stress concentration, and propose the stress concentration alleviation method that will make better efficient pipe system and will have a good effect on economic, social aspect.

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Molecular dynamics study of Al solute-dislocation interactions in Mg alloys

  • Shen, Luming
    • Interaction and multiscale mechanics
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    • v.6 no.2
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    • pp.127-136
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    • 2013
  • In this study, atomistic simulations are performed to study the effect of Al solute on the behaviour of edge dislocation in Mg alloys. After the dissociation of an Mg basal edge dislocation into two Shockley partials using molecular mechanics, the interaction between the dislocation and Al solute at different temperatures is studied using molecular dynamics. It appears from the simulations that the critical shear stress increases with the Al solute concentration. Comparing with the solute effect at T = 0 K, however, the critical shear stress at a finite temperature is lower since the kinetic energy of the atoms can help the dislocation conquer the energy barriers created by the Al atoms. The velocity of the edge dislocation decreases as the Al concentration increases when the external shear stress is relatively small regardless of temperature. The Al concentration effect on the dislocation velocity is not significant at very high shear stress level when the solute concentration is below 4.0 at%. Drag coefficient B increases with the Al concentration when the stress to temperature ratio is below 0.3 MPa/K, although the effect is more significant at low temperatures.

Effect of Ginseng Saponin on Adrenaline-Induced Hyperglycemia and Hyperlipidemia (인삼사포닌이 Adrenaline에 의한 고혈당 및 고지방혈증에 미치는 영향)

  • 이동권;임창진;박은희;홍순근
    • YAKHAK HOEJI
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    • v.25 no.2
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    • pp.49-55
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    • 1981
  • To elucidate the effect of ginseng saponin on adrenaline-induced hyperglycemia and hyperlipidemia, ginseng saponin was administered before and after administration of adrenaline, and concentration of glucose, triglyceride(TG), and free fatty acid (FFA) as well as lipase activity in plasma was determined. 1) Glucose concentration was slightly increased by administration of ginseng saponin at 1 hour before and 10 minutes after adrenaline administration, but decreased by administration of ginseng saponin at 7 and 4 hours before adrenaline administration. TG and FFA concentration was also greatly inhibited by administration of ginseng saponin in advance. 2) When gineseng saponin 3, 10, 30mg/kg were administered 7 hours before adrenaline administration, glucose and TG concentration as well as lipase activity were inhibited in proportion to the dose of ginseng saponin, but FFA concentration was slightly inhibited. 3) It was suggested that protopanaxatriol group have potentiating effect on adrenaline induced hyperglycemia but protopanaxadiol group have inhibitory effect. And ginseng saponin seems to have strong inhibitory action on TG mobilization into blood and stimulatory effect on esterification of FFA in liver and adipose tissue.

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Direct Evidence of Endophyte (Neotyphodium coenophialum) Genotype Effect on Growth and Vertical Transmission of Endophyte in Tall Fescue (Schedonorus phoenix Scop.) Under Water Stress

  • Ju, Ho-Jong
    • The Plant Pathology Journal
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    • v.27 no.3
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    • pp.249-256
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    • 2011
  • Tall fescue (Schedonorus phoenix Scop.) is resistant to abiotic and biotic stresses through a symbiotic relationship with Neotyphodium coenophialum. However, this endophyte has been considered detrimental since it produces toxic alkaloids to animals. It is vital to understand mutuality between these two to maximize positive impact of the endophyte on agri-ecosystem. Little research has been conducted on endophyte transmission mechanism in planta. To provide basic information related to endophyte transmission, an experiment was conducted to examine the effect of endophyte genotype and water stress on endophyte transmission by imposing soil moisture deficits at different stages of panicle development. There was water stress effect on endophyte frequency but not on concentration, whereas endophyte genotype significantly influenced endophyte concentration in pseudostem of tall fescue at boot stage. Reproductive tillers showed greater endophyte frequency and concentration. Endophyte frequency in florets or seeds depended on position within panicle. There was no drought effect on endophyte concentration, but showed the effect of endophyte genotype on endophyte concentration in florets and seeds. Overall endophyte concentration in seeds was higher. From this study, we may conclude that although water stress reduced endophyte frequency in vegetative tiller, water stress does not have effect on endophyte transmission, suggesting that drought is not an important factor controlling the endophyte transmission from plant to seed. Endophyte genotype and seed position in a panicle affected endophyte transmission, indicating that these two factors are involved in endophyte transmission and may determine seed transmission of endophyte in tall fescue.

Stress concentration and deflection of simply supported box girder including shear lag effect

  • Yamaguchi, Eiki;Chaisomphob, Taweep;Sa-nguanmanasak, Jaturong;Lertsima, Chartree
    • Structural Engineering and Mechanics
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    • v.28 no.2
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    • pp.207-220
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    • 2008
  • The shear lag has been studied for many years. Nevertheless, existing research gives a variety of stress concentration factors. Unlike the elementary beam theory, the application of load is not unique in reality. For example, concentrated load can be applied as point load or distributed load along the height of the web. This non-uniqueness may be a reason for the discrepancy of the stress concentration factors in the existing studies. The finite element method has been often employed for studying the effect of the shear lag. However, not many researches have taken into account the influence of the finite element mesh on the shear lag phenomenon, although stress concentration can be quite sensitive to the mesh employed in the finite element analysis. This may be another source for the discrepancy of the stress concentration factors. It also needs to be noted that much less studies seem to have been conducted for the shear lag effect on deflection while some design codes have formulas. The present study investigates the shear lag effect in a simply supported box girder by the three-dimensional finite element method using shell elements. The whole girder is modeled by shell elements, and extensive parametric study with respect to the geometry of a box girder is carried out. Not only stress concentration but also deflection is computed. The effect of the way load is applied and the dependency of finite element mesh on the shear lag are carefully treated. Based on the numerical results thus obtained, empirical formulas are proposed to compute stress concentration and deflection that includes the shear lag effect.