• Journal of Ginseng Research
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• v.14 no.1
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• pp.10-13
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• 1990

Effect of an acidic polysaccharide fraction In Korean white and red ginseng on lipolytic action of Toxohormone-L was studied. Crude acidic polysaccharide fraction was extracted from main and lateral root of Korean white and red ginseng separately and purified several times. Inhibitory effect of crude polysaccharide fraction was determined by unit (1 unit is loft inhibition rate per Is sample). Yields of purified crude polysaccharide fraction of main and lateral root of red ginseng were 2.9 and 2.2 times higher than those of white ginseng, respectively. Inhibitory effects of main root of white and red ginseng, 11.hen final reaction concentrations of sample were 50, 100, 200, 500 $\mu$g/ml, were 37.2가 and 23.7% higher than those of lateral root of white and red ginseng. Inhibitory effect of main root of red ginseng was 2.3 times higher than that of white ginseng.

• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.469-474
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• 2000

Effect of the antibiotic carbenicillin on callus and shoot formation from the leaf disc culture of tobacco (Nicotiana tabacum L. cv. BY-4) was examined. The number of shoot induced from the leaf explants was decreased as the amount of carbenicillin increased from 250 mg/L to 2,000 mg/L on MS medium containing 0.5 mg/L of BAP or kinetin. In addition, calli formation from the leaf explants was increased by the treatment of 250 mg/L ∼ 500 mg/L carbenicillin with or without 0.5 mg/L of 2,4-D or NAA. However, the fresh weight of 4-week-cultured explants was decreased with increasing carbenicillin from 250 mg/L to 2,000 mg/L on MS medium containing 0.5 mg/L of 2,4-D or NAA. These results indicate that carbenicillin has an auxin-like effect, such as promoting callus formation and inhibiting shoot induction. It leads to the conclusion that the auxin-like property should be taken into account for the production of transgenic plants via Agrobacterium-mediated transformation.

• Plant Resources
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• v.4 no.1
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• pp.53-58
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• 2001

The effect of carbenicillin on the dedifferentiation and the regeneration efficiency of plant tissues of horseradish(Armoracia rusticana) was evaluated, Inhibition effect for callus initiation was observed when leaf blade, root and petiole segments were grown on MS medium containing 500 mg/L to 2000 mg/L carbenicillin and 0.5 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D). The regeneration of horseradish shoots from leaf blade, root and petiole explants were decreased as the addition of carbenicillin increased from 1000 mg/L to 2000 mg/L in MS medium containing 0.5 mg/L of 6-benzylaminopurine (BAP) or kinetin. Especially, 500 mg/L carbenicillin treatment significantly inhibited shoot induction when leaf blade explants were grown on hormone-free MS medium. It was suggested that the toxic effects of combinations of carbenicillin and 2,4-D may be due to high auxin activity levels.

• Phonetics and Speech Sciences
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• v.8 no.4
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• pp.15-22
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• 2016

This study aims to examine whether the fundamental frequency (F0) varies depending on languages or distinguishes between L1 (first language) and L2 (second language) speech and whether the type of materials which vary in control of consonant voicing affects the use of F0-especially, mean F0. For this purpose, we compared productions of two languages produced by Korean L2 learners of English to those of Korean-English bilingual speakers. Twelve Korean L2 speakers of English and twelve Korean-English bilingual speakers participated in this study. The subjects read aloud 22 declarative sentences-balanced and unbalanced-once in English and once in Korean. Mean F0 of Korean was higher than that of English for both speaker groups, and the difference in the value of mean F0 between the Korean and English sentences was different depending on the type of materials that the participants read. With regard to F0 range, the L2 speakers had a larger F0 range in English than in Korean; however, the effect of language on F0 range was not statistically significant for the bilingual speakers. These results indicate that language-specific properties may affect the use of F0, in particular, mean F0.

• Language and Information
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• v.14 no.1
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• pp.67-91
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• 2010

Present study examines L1 transfer effect and UG involvement in the acquisition of binding properties of Korean as second language (L2). The study especially investigates i) whether knowledge from different L1s (English and Chinese) affect the interpretation of binding in Korean as L2 and ii) whether L2 learners of Korean differentiate two Korean anaphors like Korean monolinguals do, based on their knowledge of universal form-function correlation of anaphors. 53 post-puberty L2 learners of Korean with English or Chinese L1, together with 30 Korean monolinguals, were tested over Truth Value Judgment Task with stories, composed of Korean sentences representing various types of binding with two Korean reflexives - caki and caki-casin. The results showed some effect of L1 transfer, though not always. Overall, late L2 learners of Korean seem to know the difference between the two anaphors in their properties related to form-function correlation, though their performance level was lower compared to Korean monolinguals. Detailed pattern of the results and the role of UG in the interpretations of Korean reflexives are also discussed.

• Natural Product Sciences
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• v.6 no.2
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• pp.56-60
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• 2000

We investigated that the extract of Aloe vera L. and its fractions exert antimutagenic activity against Salmonella typhimurium TA98 and TA100, and antileukemic effect against K562 human leukemia cell line. The aqueous ethanolic extract of A. vera L. was revealed to have antimutagenic effect on the AF-2 (2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide) in Salmonella mutation assay. Among the three fractions (fractions A, B and C) separated by silica gel chromatography, fraction C $(50\;{\mu}g/plate)$ exhibited the greatest antimutagenic effect on the AF-2 with inhibition rate of 84 and 90% in Salmonella typhimurium TA98 and TA100, respectively. The fraction C $(500\;{\mu}g/ml)$ inhibited the growth of K562 human leukemia cell line by 93% in MTT assay. However, the components of A. vera L. did not exhibit cytotoxic effect against MDBK bovine normal kidney in MTT assay.

• Korean Journal of Pharmacognosy
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• v.44 no.4
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• pp.379-383
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• 2013

Portulaca oleracea L. is known to have many biological benefits such as anti-oxidant, anti-inflammatory, anti-allergic and anti-tumor. The objective of this study is to explore the neuroprotective effect of P. oleracea L. against glutamate-induced oxidative stress in mouse hippocampal HT22 cells. P. oleracea L. 70% ethanol extract and solvent fractions have the potent neroprotective effects on glutamate-induced nerotoxicity by induced the expression of heme oxygenase (HO)-1 in HT22 cells. Especially, ethyl acetate fraction showed higher protective effect. In HT22 cell, P. oleracea L. treatment with ERK inhibitor (PD98059) and c-JUN N-terminal kinase (JNK) inhibitor (SP600125) reduced P. oleracea L. ethyl acetate fraction induced HO-1 expression and P. oleracea L. ethyl acetate fraction also increased ERK and JNK phosphorylation. Furthermore, we found that treatment of P. oleracea L. caused the nuclear accumulation of Nrf2. In conclusion, the ethyl acetate fraction of 70% ethanol extract of P. oleracea L. significantly protect glutamate-induced oxidative damage by induction of HO-1 via Nrf2, ERK and JNK pathway in mouse hippocampal HT22. Taken together these finding suggest that P. oleracea L. ethyl acetate fraction is good source for taking active compounds and may be a potential therapeutic agent for brain disorder that induced by oxidative stress and neuronal damage.

• The Korean Journal of Pain
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• v.19 no.2
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• pp.142-145
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• 2006

Background: Nitric oxide (NO) is involved in the transmission and modulation of nociceptive information at the peripheral, spinal cord and supraspinal levels. We conducted this experiment to assess the antinociceptive effects of a nonselective nitric oxide synthase (NOS) inhibitor, N-nitro-L-arginine methyl ester (L-NAME), on the modulation of pain in rats subjected to the formalin test. Methods: Formalin 5% was injected in the right hind paw after intraperitoneal (IP) injection of various doses of L-NAME (0.5 mg/kg, 1.5 mg/kg with and without L-arginine 100 mg/kg, 5.0 mg/kg). The number of flinches was measured. Results: Formalin injected into the rat hind paw induced a biphasic nociceptive behavior. IP injected L-NAME diminished the nociceptive behaviors in a dose-dependent manner during phases 1 and 2. The concomitant injection of L-arginine reversed the antinocipetive effect of L-NAME. Conclusions: The data demonstrates that a nonselective NOS inhibitor, L-NAME, possesses antinociceptive properties in rats subjected to the formalin test, and the antinociceptive effect of L-NAME is reversed by the concomitant administration of L-arginine.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.3
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• pp.143-149
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• 2018

Background: We evaluated the changes in mean arterial pressure (MAP) and heart rate (HR), and the anesthetic and hemostatic effects, after injection of 2% lidocaine containing various concentrations of epinephrine in rats and mice to determine the appropriate concentration of epinephrine in various anesthetic mixtures. Methods: Rats and mice were randomly allocated to experimental groups: 2% lidocaine without epinephrine (L0), 2% lidocaine with epinephrine 1:200,000 (L200), 1:100,000 (L100), and 1:80,000 (L80). Changes in MAP and HR after administration of the anesthetic mixture were evaluated using a physiological recording system in rats. Onset and duration of local anesthesia was evaluated by pricking the hind paw of mice. A spectrophotometric hemoglobin assay was used to quantify the hemostatic effect. Results: MAP increased in response to epinephrine in a dose-dependent manner; it was significantly higher in the L80 group than in the L0 group at 5 min post-administration. The HR was relatively lower in the L0 group than in the L80 group. The time required for onset of action was < 1 min in all evaluation groups. The duration of action and hemostatic effect of the local anesthetic were significantly better in the L200, L100, and L80 groups than in the L0 group. Conclusion: L200 demonstrated relatively stable MAP and HR values with satisfactory efficacy and hemostatic effect. L200 might be a better local anesthetic for dental patients in terms of anesthetic efficacy and safety.

• Journal of Software Assessment and Valuation
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• v.16 no.2
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• pp.153-162
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• 2020

Digital image forgery detection is one of very important fields in the field of digital forensics. As the forged images change naturally through the advancement of technology, it has made it difficult to detect forged images. In this paper, we use passive forgery detection for copy paste forgery in digital images. In addition, it detects copy-paste forgery using the L₀ Norm-based LE operator, and compares the detection accuracy with the forgery detection using the existing L₂, L₁ Norm-based LE operator. In comparison of detection rates, the proposed lower triangular(Ayalneh and Choi) window was more robust to BAG mismatch detection than the conventional window filter. In addition, in the case of using the lower triangular window, the performance of image forgery detection was measured increasingly higher as the L₂, L₁ and L₀ Norm LE operator was performed.