• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.6
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• pp.845-856
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• 2017

In the long railway tunnel, in order to secure safety in case of fire, it is required a emergency station. However, there is no standard or research results on smoke exhaust method and exhaust flow rate in emergency station, so it is necessary to study the smoke exhaust system for emergency station. In this study, we are created a numerical analysis model for emergency station where the evacuation cross passage connected to the service tunnel or the relative tunnel was installed at regular intervals (40 m intervals). And the fire analysis are carried out by varying the fire intensity (15, 30MW), the smoke exhaust method (only air supply, forced air supply and exhaust, forced air exhaust only), and the air flow rate (7, 14, $40m^3/s$). From the results of fire analysis, temperature and CO concentration are analyzed and ASET based on the limit temperature are compared at various condition. As a result, in the case with fire intensity of 15 MW, it is shown that a sufficiently safe evacuation environment can be ensured by applying forced air supply and exhaust method or forced air exhaust only method when the air flow rate is $7m^3/s$ above. In case of fire intensity of 30 MW, it is impossible to maintain the safety evacuation environment for more than 900 seconds when the exhaust air volume is below $14m^3/s$. And when the air flow rate is $40m^3/s$, the exhaust port is disposed at the side portion of the upper duct, which is most advantageous for securing the temperature-based safety.

• Clinical and Experimental Reproductive Medicine
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• v.38 no.3
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• pp.168-173
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• 2011

Objective: To examine the association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and hyperhomocysteinemia in women with unexplained recurrent miscarriages (RM) and to investigate the association between MTHFR genotype variants and alloimmune activation, proportion of peripheral blood natural killer (pbNK) cells. Methods: A total of 39 patients with a history of two or more unexplained miscarriages were recruited to this study. The controls were women who had a live birth without a history of RM (n=50). The proportion of pbNK cells was measured by flow cytometry. Plasma homocysteine levels and the incidence of the MTHFR variant of the RM and control groups were compared. The proportion of pbNK cells was compared to the MTHFR variants in the RM group. Results: No differences were found between the two groups' mean plasma homocysteine levels ($7.6{\pm}1.5{\mu}mol$/L vs. $7.1{\pm}2.1{\mu}mol$/L) or incidence of the MTHFR genotype variant (CC, 35% vs. 33%; CT, 40% vs. 53%; and TT, 25% vs. 14%). In the RM group, individuals with the TT variant ($7.7{\pm}1.1{\mu}mol$/L) had higher homocysteine levels than those with the CC and CT variants ($7.4{\pm}1.9{\mu}mol$/L and $7.4{\pm}1.2{\mu}mol$/L) and those with the CT variant ($19.2{\pm}8.1%$) had a higher proportion of CD3-/CD56+ pbNK cells than those with the CC and TT variants ($17.7{\pm}6.6%$ and $17.9{\pm}7.0%$), but the results of both comparisons were statistically insignificant. Conclusion: These preliminary results show no difference in plasma homocysteine levels between the RM and control groups or among MTHFR genotype variants in the RM group, which may suggest that the plasma homocysteine level is difficult to use as a predictive marker of RM in the Korean population. A study of a larger number of patients is needed.

• Korean Journal of Community Nutrition
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• v.16 no.6
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• pp.730-739
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• 2011

The purpose of this study was to analyze the differences between child-care facilities and kindergartens towards the need for foodservice support by Center for Child-Care Foodservice Management (CCFSM). For this study, questionnaires were sent out from August of 2008 to April of 2009 to directors of 1,478 child care facilities and 299 kindergartens in Seoul and Gyeonggi-do via postal service. A total of 267 questionnaires were usable with 203 (13.7%) of child-care facilities and 64 (21.4%) of kindergartens. Statistical data were analyzed by SPSS 15.0 for descriptive analysis and t-test. For political and administrative support, government funding for foodservice was the highest need and hiring nutritionists was significantly different by type of facility (p < 0.01). Both child-care facilities (4.29) and kindergartens (4.41) demanded the balanced menu from CCFSM. There were significant differences of "information about food material sanitation management" (p < 0.05), "hygiene safety management method according to working process" (p < 0.05), "hygiene safety management method of foodservice facilities and equipment" (p < 0.05). In education and training contents from center, "types and methods to manage foodservice facilities and equipment" for directors, "dietary education by age" for teachers, and "the rules of personal sanitation and working process" and "gas, electricity and fire prevention" for culinary workers had the highest mean score of requirements.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.543-550
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• 2009

The single-crystal structure of largely ammonium-exchanged zeolite Y dehydrated at room temperature (293 K) and 1 ${\times}\;10^{-6}$ Torr. has been determined using synchrotron X-radiation in the cubic space group $Fd\overline{3}m\;(a=24.9639(2)\AA)$ at 294 K. The structure was refined to the final error index $R_1$ = 0.0429 with 926 reflections where $F_o>4\sigma(F_o)$; the composition (best integers) was identified as |$(NH_4)_{60}Na_{11}$|[$Si_{121}Al_{71}O_{384}$]-FAU. The 11 $Na^{+}$ ions per unit cell were found at three different crystallographic sites and 60 ${NH_4}^{+}$ ions were distributed over three sites. The 3 $Na^{+}$ ions were located at site I, the center of the hexagonal prism ($Na-O\;=\;2.842(5)\;\AA\;and\;O-Na-O\;=\;85.98(12)^{\circ}$). The 4 $Na^{+}$ and 22 ${NH_4}^{+}$ ions were found at site I' in the sodalite cavity opposite the double 6-rings, respectively ($Na-O\;=\;2.53(13)\;\AA,\;O-Na-O\;=\;99.9(7)^{\circ},\;N-O\;=\;2.762(11)\;\AA,\;and\;O-N-O =\;89.1(5)^{\circ}$). About 4 $Na^{+}$ ions occupied site II ($(Na-O\;=\;2.40(4)\;\AA\;and\;O-Na-O\;=\;108.9(3)^{\circ}$) and 29 ${NH_4}^{+}$ ions occupy site II ($N-O\;=\;2.824(9)\;\AA\;and\;O-N-O\;=\;87.3(3)^{\circ}$) opposite to the single 6-rings in the supercage. The remaining 9 ${NH_4}^{+}$ ions were distributed over site III' ($N-O\;=\;2.55(3),\;2.725(13)\;\AA\;and\;O-N-O\;=\;94.1(13),\;62.16(15),\;155.7(14)^{\circ}$).

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.4
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• pp.361-369
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• 2008

The purpose of this study is to make porous oxide film on the surfaces of pure Ti through anodic spark discharge in electrolytic solution containing calcium and phosphate ions, to improve osseointergration by treating fluoride agent. In addition, it is to evaluate the fluoride modified effect on the surface. Commercial pure Ti plate with $20{\times}10{\times}2mm$ and Ti wire with a diameter of 1.5mm and a total length of 15mm were used. After making titanium oxide films converted by anodic spark discharge, anodizing was performed. Fluoride was spreaded to titanium laboratory plate and maintained for 30 minutes after anodizing breakdown. Fluoride ion discharge amount was measured per 24 hours after dipping titanium plate into saline (10ml) and sustaining 90rpm in a pyrostat. Some plates and wires were dipped in Hanks solutions for a month to examine biocompatibility using SEM and XRD. $TiO_2$ film formed by anodic discharge technique showed great roughness and uniform pores which were $1{\sim}3{\mu}m$ in a diameter. Roughness of the films treated with anodic discharge after blasting were higher than the turned ones(P<0.05). Rapid surface activity was observed in the samples treated with $TiF_3$ agent, which immersed in Hanks solution for 30 days. Taking the results into consideration, the fluoride modified implant with anodic discharge demonstrates that it makes uniformly porous oxide film on the surface of implant and properly increase roughness for osseointegration. The implants will achieve greater bone integration after short healing time by improving surface activity.

• Mycobiology
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• v.46 no.1
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• pp.64-71
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• 2018

The aim of this study was to investigate the pattern of distribution of mating type (MAT) genes of Tuber indicum in ectomycorhizosphere soils from natural T. indicum-producing areas and cultivated truffle orchards and ascocarp samples from different regions. Quantitative real-time PCR and multiplex PCR were used to weight the copy numbers of MAT1-1-1 and MAT1-2-1 in natural truffle soils and cultivated orchard soils. The effect of limestone on the pattern of truffle MAT genes and the correlation between soil properties and the proportion of MAT genes were also assessed. These results indicated that an uneven and nonrandom distribution of MAT genes was common in truffle-producing areas, cultivated truffle orchards, and ascocarps gleba. The competition between the two mating type genes and the expansion of unbalanced distribution was found to be closely related to truffle fructification. Limestone treatments failed to alter the proportion of the two mating type genes in the soil. The content of available phosphorus in soil was significantly correlated with the value of MAT1-1-1/MAT1-2-1 in cultivated and natural ectomycorhizosphere soils. The application of real-time quantitative PCR can provide reference for monitoring the dynamic changes of mating type genes in soil. This study investigates the distributional pattern of T. indicum MAT genes in the ectomycorhizosphere soil and ascocarp gleba from different regions, which may provide a foundation for the cultivation of T. indicum.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.115-121
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• 1988

Although Saponin A from Panax ginseng has previously been shown to inhibit carageenin induced edema. a paucity of information exists on the effects of components from ginseng on the cellular inflammatory response. specifically polymorphonuclear leukocyte (PMNL) function. The purpose of this study was 10 determine the effects of isolated neutral dammarane saponins from ginseng (i.e..glycosidic derivatives of 20(S)-protopanaxadiol [ginsenoside $Rb_1,\;Rb_2$ and Rc] and 20(S)-protopanaxatriol [ginsenosides Re and $Rg_1$]) on in vivo PMNL function and to compare their effects with those produced by a steroidal anti-inflammatory agent (dexamethasone) and commercially available saponin. Dexamethasone. the ginsenosides and saponin were all shown to he potent inhibitors of PMNL chemotaxis using the $^{51}Cr$ assay with $5{\times}10^{-8}M$ f-met-leu-phe [FMLP] as the chemoattractant. Inhibition or PMNL chemotaxis by dexamethasone. the ginsenosides and saponin were all shown to be both time-and dose-dependent and these agents did not affect cellular viability at the concentrations tested Saponin and the ginsenosides were more potent inhibitors of chemotaxis than was dexamethasone. while oxidant generation (as measured by the luminol-enhaneed chemil-uminescence of PMNL using FMNL $[10^{-6}]$ as the stimulus) was inhibited by dexamethasone. the ginsenosides $(Rb_1\;Rb_2\;Rc\;Re\;and\;Rg_1)$ and saponin at a concentration of 1 ${\mu}M$ had no significant effect on PMNL chemiluminescence. Thus. the neutral dammarane saponins are potentially important modulators or PMNL function and their inhibitory effects may he differentiated from those of the Steroidal anti-inflammatory agents.

• Journal of Convergence for Information Technology
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• v.10 no.3
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• pp.195-199
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• 2020

This study examined the effect of the nervous-system-stimulating caffeine on the nerve conduction velocity. The purpose of this study is to investigate the effect of caffeine that stimulates the nervous system on nerve conduction test. Although both measurement intervals did not show statistically significant differences when comparing the pre- and post-NCV values within the control and individual experimental groups, it was found that the nerve conductivity in the Axilla-Above Elbow section increased significantly after caffeine intake for the experimental group. Caffeine intake, which has increased the nerve conduction velocity (NCV), was determined to play roles in improving motor skills, muscle strength and nerve performance by temporarily increasing the nerve conduction velocity. Through this study, we learned that caffeine has an influence on the peripheral nervous system as it helps to improve the nerve conduction velocity. upon an appropriate amount of caffeine intake. We hope that these results will help develop treatment and diagnostic methods for patients with nerve dysfunction and myofunctional disorders.

• Food Science and Preservation
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• v.24 no.1
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• pp.100-106
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• 2017

This study was conducted to evaluate the genotoxicity of balanced nutritional formular for patients containing various ingredients after gamma irradiation at 4 kGy. Since viable bacteria were not observed within the detection limit of 1 log CFU/g, a dose of 4 kGy was appropriate for the pasteurization of the formular. In a bacterial reverse mutation assay, both hot water and methanol extracts of the formular exhibited dose-independent responses, which was similar to those obtained from that of the negative control (distilled water or dimethyl sulfoxide). In a chromosomal aberration test using lung fibroblast cells of Chinese hamster, the numbers of normal chromosomes were comparable to those observed in the negative control, regardless of the treatment dose and metabolic activation system. Furthermore, no significant increases in the frequency of micronucleated polychromatic erythrocytes were observed relative to the control, when mice were fed with the formular at doses up to 2,000 mg/kg body weight. Therefore, the balanced nutritional formular for patients did not exhibit genotoxicity when pasteurization by gamma irradiation at 4 kGy.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.60-68
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• 1998

The effect of P. agarici and P. tolaasii causing the bacterial disease of mushrooms on the mycelial growth and fruitbody formation of F. velutipes was evaluated in laboratory. When the pathogenic bacteria was inoculated simultaneously with F. velutipes or 5 days after inoculation of F. velutipes, they significantly deterred both mycelial growth and fruitbody formation of F. velutipes in sawdust culture and showed strong inhibition under high population density. They appeared to be tender or milky in exhibiting symptom on F. velutipes by inoculating the concentration of $10^2{\sim}10^6$ of unit/g media, and their growth seemed to be stopped under $10^8\;cfu/g$ media. On $10^2\;cfu/g$ media of P. agarici and $10^4\;cfu/g$ media of P. tolaasii, there was no effect on the fruitbody yield of F. velutipes. P. tolaasii was more suppressive in the mycelial growth of F. velutipes than P. agarici, while on fruitbodies formation of F. velutipes, P. agarici showed slightly higher inhibition than that of P. tolaasii. When the bacteria was inoculated 10 days after inoculation of F. velutipes, both mycelial growth and fruit body formation were not affected nearly.