• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2105-2113
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• 1995

The compressive tests under impact conditions were performed to establish a design guide for impact damage tolerance. The composition of layup was selected for the real cases of composite aircraft structure. The energy level of visible of visible damage threshold was determined as 7 Joules. It was found that the normalized bending stiffnesses in the direction of closely fixed boundary affected the area of damage. Graphite/epoxy used in the tests exhibited 60% reduction in compression strength at the energy level of visible damage threshold. Wet-conditioned specimens represented 9% reduction in residual compressive strength in comparison with room temperature ambient specimens. In this study, a design factor of 2.1 was proposed for the low velocity impact damage.

• Proceedings of the Ginseng society Conference
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• 1990.06a
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• pp.36-44
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• 1990

The analgesic effect of morphine was antagonized and the development of tolerance was suppressed by the modification of the neurologic function in the animals treated with ginseng saponins. The activation of the spinal descending inhibitory systems as well as the supraspinal structures by the administration of morphine was inhibited in the animals treated with ginseng saponins intracerebrally or intrathecally The development of morphine tolerance and dependence, and the abrupt expression of naloxone induced abstinence syndrome were also inhibited by ginsenoside Kbl , Rba, Rgl and Re. These results suggest that ginsenoside Kbl, Rba, Rgl and Re are the bioactive components of panax ginseng on the inhibition of the development of morphine tolerance and dependence, and the inhibition of abrupt abstinence syndrome. In addition, further research on the minor components of Panax ginseng should be investigated. A single or daily treatment with ginseng saponins did not induce any appreciable changes in the brain level of monoamines at the various time intervals and at the various day intervals, respectively The inhibitory or facilitated effects of ginseng saponins on electrically evoked contractions in guinea pig ileum (U-receptor) and mouse was definers (5·receptor) were not mediated through opioid receptors. The antagonism of a x receptor agonist, U-, iO.488H was also not mediated through opioid receptors in the animals treated with ginseng saponins, bolt mediated through serotonergic mechanisms. Ginseng saponins inhibited morphine S-dehydrogenase that catalyzed the production of morphine from morphine, and increased hepatic glutathione contents for the detoxification of morphine. This result suggests that the dual action of the above plays an important role in the inhibition of the development of morphine tolerance and dependence.

• BMB Reports
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• v.43 no.5
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• pp.330-336
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• 2010

5-Aminolevulinate (ALA) is well-known as an essential biosynthetic precursor of all tetrapyrrole compounds, which has been suggested to improve plant salt tolerance by exogenous application. In this work, the gene encoding aminolevulinate synthase (ALA-S) in yeast (Saccharomyces cerevisiae Hem1) was introduced into the genome of Arabidopsis controlled by the Arabidopsis thaliana HemA1 gene promoter. All transgenic lines were able to transcribe the YHem1 gene, especially under light condition. The chimeric protein (YHem1-EGFP) was found co-localizing with the mitochondria in onion epidermal cells. The transgenic Arabidopsis plants could synthesize more endogenous ALA with higher levels of metabolites including chlorophyll and heme. When the $T_2$ homozygous seeds were cultured under NaCl stress, their germination and seedling growth were much better than the wild type. Therefore, introduction of ALA-S gene led to higher level of ALA metabolism with more salt tolerance in higher plants.

• The Journal of the Acoustical Society of Korea
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• v.22 no.6
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• pp.496-504
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• 2003

In this paper, the error tolerance of each array element to ensure a given specified error level for the array pattern is analyzed using the Genetic Algorithm. In the conventional deterministic method for synthesis of sonar way problems the computational resource required in the simulation grows rapidly as the number of way elements increases. To alleviate this numerical inefficiency, the Monte-Carlo method may be considered as an alternative technique for array syntheses. However, it is difficult to apply the method to the synthesis of array patterns because of its relatively lower accuracy in spite of moderate computational complexity. A new analysis method for estimating error tolerances in sonar arrays is Proposed since the Genetic Algorithm has significant promise to efficiently solve way synthesis problems. Through several numerical tests in linear and planar arrays, it is demonstrated that the proposed method can provide accurate results for error tolerances of sonar arrays.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.872-877
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• 1997

Soybean curd whey(SCW) containing plenty of nutrients is the discarded by-product in soybean curd processing. To test the potential utilization of SCW as a medium for the cultivation of Lactobacilus acidophilus, the chemical composition of SCW, as well as the growth, acid production, acid-tolerance, and bile-tolerance of L. acidophilus in SCW-based media were investigated. Sucrose and stachyose, the main free sugars of SCW, were 0.42% and 0.41%, respectively. SCW contained 36.1mg/L of total free amino acids. L. acidophilus KFRI 150 showed lower cell growth and acid production in SCW than those in MRS broth. In optimized SCW-based medium supplemented with 1.0% glucose, 0.5% yeast extract, and 0.2% $K_{2}HPO_{4}$, the growth and acid production of L. acidophilus KFRI 150 increased by twice against those in SCW. In optimized SCW-based medium, the viable counts of four L. acidophilus strains were mostly at the level of $10^{9}$/ml, which is similar to those in MRS broth. Each acid-tolerance and biletolerance of four L. acidophilus strains cultured in optimized SCW-based medium and MRS broth showed no dist-inguishable difference.

• IMMUNE NETWORK
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• v.11 no.6
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• pp.358-363
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• 2011

Background: Traditionally, interferon-${\gamma}$ (IFN-${\gamma}$) was regarded as a pro-inflammatory cytokine, however, recent reports suggested role of IFN-${\gamma}$ in immune tolerance. In our previous report, we could induce tolerance to male antigen (HY) just by male islet transplantation in wild type C57BL/6 mice without any immunological intervention. We tried to investigate the influence of IFN-${\gamma}$ deficiency on tolerance induction by male islet transplantation. Methods: To examine the immunogenicity of male tissue in the absence of IFN-${\gamma}$, we transplanted male IFN-${\gamma}$ knock-out (KO) skin to female IFN-${\gamma}$ KO mice. Next, we analyzed male IFN-${\gamma}$ KO islet to streptozotocin-induced diabetic female IFN-${\gamma}$ KO mice. And, we checked the functionality of grafted islet by graft removal and insulin staining. Results: As our previous results in wild type C57BL/6 mice, female IFN-${\gamma}$ KO mice rejected male IFN-${\gamma}$ KO skin within 29 days, and did not reject male IFN-${\gamma}$ KO islet. The maintenance of normal blood glucose level was dependent on the presence of grafted male islet. And the male islet recipient did not reject 2nd challenge of male islet graft also. Conclusion: Deficiency of IFN-${\gamma}$ does not have influence on the result of male skin graft and male islet transplantation. Conclusively, male islet transplantation induced T cell tolerance is not dependent on the presence of IFN-${\gamma}$.

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.411-416
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• 2010

In this research, we intended to improve the tolerance of thick film resistor using photosensitive polymer resistor paste which was fabricated with alkali-solution developable photosensitive resin and conductive carbon black. At first, we investigated the effect of the selection of carbon black and photosensitive resin on the resistance range and tolerance level of polymer thick film resistor (PTFR). And then, a difference in resistance tolerance was evaluated according to the coating methods of photosensitive resistor paste on test board. In case that the photosensitive resistor paste was coated on whole surface of test board using screen printing, large positional tolerance was obtained because the formation of the thick film with uniform thickness was difficult. On the other hand, when the paste was coated with roller, the resistive thick film with uniform thickness was formed on the whole board area and the result of resistance evaluation showed low tolerance in ${\pm}10%$ range. The tolerance of PTFR could be improved by combination of the precise patterning using photo-process and the coating process for the resistive thick film with uniform thickness.

• Biomolecules & Therapeutics
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• v.13 no.1
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• pp.13-19
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• 2005

The study was undertaken to determine the antagonism of the AP1700 on the development of nalbuphine-induced tolerance and physical dependence. AP1700 is an oriental drug preparationcomposed of 5 natural products and is known to have antinarcotic action with an oral dose of 250 mg/kg in rats. AP1700 significantly inhibits the development of antinarcotic action with an oral dose of 250 mg/kg in rats. AP1700 significantly inhibits the development of nalbuphine-induced physical dependence but does not the tolerance. Mitogen-activated protein kinase, which include extracellular signal-regulated kinase (ERK), p38 and c-Jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK) play critical roles in cell growth and survival and drug abuse. The level of pCREB was elevated in the hippocampus by the chronic treatment with nalbuphine, however, the elevation of pCREB was not inhibited by the AP1700 co-treatment. Interestingly, the level of pERK was decreased in the co-treatment with nalbuphine and AP1700 on the cortex and striatum. However, the level of nNOS and NR1 was not modulated by the treatment with nalbuphine or AP1700 on the cortex, hippocampus and striatum in the rat brain. These results suggest that the AP1700 could be used to ameliorate the nalbuphine withdrawal symptoms.

• Biomolecules & Therapeutics
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• v.5 no.4
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• pp.364-368
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• 1997

Onion (Allium cepa Linn) has been reported to have hypoglycemic activity in human and several animal models. In the present study, we performed intraperitoneal glucose tolerance test (IPGTT) in young (1.5mo) and aged (5 mo) rats treated with onion in order to determine whether aging can influence on the anti-hy-perglycemic effect of onion. In addition, we investigated the hypoglycemic effect of onion in streptozotocin- induced diabetic rats treated with aqueous extracts of onion (500 mg/kg, i.p., daily) for 4 weeks. Blood glucose level was determined in fasted and fed rats by using a glucometer (Johnson & Johnson). In glucose tolerance test, blood glucose level was maximally increased 15 min after glucose load (2 g/kg, i.p.), and recovered to the basal level 3 hr after glucose challenge in young and old rats. The maximum blood glucose levels of young and aged rat were 184$\pm$7.49 and 225.2$\pm$ 12.55 mg/dl, respectively. A single i.p. injection of aqueous extract of onion (1 g/kg) 30 min before glucose challenge significantly decreased blood glucose levels at 15, 30, 60, 90 min after glucose load in aged rats, while the administration of onion did not show any significant effect in young rats. In onion-treated diabetic rats, significant hypoglycemic effect (p<0.05) was observed, and the effect was greater in fasted rats than in fed. In conclusion, these results suggest that anti-hyperlycemic effect of onion can be changed by age and fasting.

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.227-231
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• 2005

We examined the effect of the subcutaneous (s.c.) pretreatment of formalin into both hind paws of mice on the antinociception induced by the intracerebroventricularly (i.c.v.) or intrathecally (i.t.) administration of ${\beta}$-endorphin using the tail-flick test. Pretreatment with formalin ($5\%$) for 5 h had no affect on the i.c.v. administered ${\beta}$-endorphin-induced tail-flick response. However, pretreatment with formalin for 40 h attenuated the tail-flick inhibition induced by i.c.v. administered ${\beta}$-endorphin. This antinociceptive tolerance to i.c.v. ${\beta}$-endorphin continued up to 1 week, but to a lesser extent. Pretreatment with formalin for 5 and 40 h significantly reduced the i.t. ${\beta}$-endorphin-induced inhibition of the tail-flick response, which continued up to 1 week. The s.c. formalin treatment increased the hypothalamic pro-opiomelanocortin (POMC) mRNA level at 2 h, but this returned to the basal level after 40 h. Our results suggest that the increase in the POMC mRNA level in the hypothalamus appears to be involved in the supraspinal or spinal ${\beta}$-endorphin-induced antinociceptive tolerance in formalin-induced inflammatory pain.