• Journal of Environmental Science International
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• v.6 no.1
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• pp.45-52
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• 1997

Methyl methanesulfonate (MMS) was fed to Drosophila melnogaster in order to investigate its toxic capability at developmental and adult stages, and the hereditary effect of toxicity and the potency for induction of sex-linked lethal mutation during the slyer-matogenesis by the means of an attached-X method. In the control group, the egg to adult viability of D. melnogaster was 95.2%, while 3. 5mM and 5.0mM treated groups were 90.0% and 84.1%, respectively. In the case of their progenies (Fl), the viability was 96.9% in the control group, while 3.5mM and 5.0mM treated groups were 54.5% and 1.6%, respectively. Therefore, these differences between two generations show significant physiological toxic effects in the next generation. In the parental generation, the developmental time was calculated 11.05 days in the control group, 12.43 days In 3.5%mM treated group, and 13.23 days in 5.0mM. In the case of Fl it was estimated 10.35 days in the control group, and 11.43 days In 3.5mM treated group. Compared with the control groups In two generations, the developmental time generally delayed as the dose of MMS increased. As to the sex-ratio, there was no differences between the control and MMS treated groups. The toxic values of adult stage showed which increased the frequency of mortality with MMS concentrations. The mortality at 120hr In the control group was 1.67% and it in 0.5mM MMS treated group 3.33%. In 2.5mM MMS treated group, it was 33.3% at 72hr, and it 95% at 120hr The increase of the morality was shown from 72hr in 4.0mM treated group which was 100% at 96hr. There was the concentration-dependent induction of sex-linked lethal mutation during the spermatogenesis by means of an attached-X method, MMS had more pronounced effect in sperm and spermaid stages in D. melnogaster.

• Journal of Oriental Neuropsychiatry
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• v.13 no.2
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• pp.195-211
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• 2002

Gagamguibitang, a composite Korean medicinal drug prescribed by us, was evaluated for its sedative effects by measurements of potentiation on pentobarbital-induced sleeping time, anticonvulsive activities in animal model, inhibitory effect on GABA transaminase activity, and antioxidative activities in vitro- and/or in vivo assay. The results were summerized as follows : 1. Gagamguibitang showed about 2-fold prolongation of pentobarbital-induced sleeping time compared to the control group after administration(p.o) with 2.0g/kg of mice body weight. 2. Gagamguibitang strongly lengthened onset time of pentylenetetrazole-induced convulsion, shortened the duration of convulsion and diminished the lethality after treatment(p.o) with 1.0g/kg of mice body weight. 3. Gagamguibitang inhibited dose-dependently the brain GABA transaminase activity in vitro compared to the control group and in vivo compared to the pentylenetetrazole-treated group. 4. Gagamguibitang inhibited effectively brain lipid peroxidation by 45.8% at a dose of l0mg/ml in vitro and by 47.5% after oral treatment with 0.5g/kg of mice body weight in vivo assay. 5. Gagamguibitang exhibited a potent scavenging activity on DPPH radical in a dose-dependent manner with ca. 92% activity at l0mg/ml. As a result, Gagamguibitang can be useful for the effective sedative drug in clinical application.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.85-88
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• 2008

Performance evaluation of RC bridge piers repaired by CFRP has been investigated. For this purpose, simplified CFRP stress-strain relationship has been proposed and use is made of inelastic time-dependent element developed by authors. Static time-history analysis has been carried out for a RC bridge pier repaired with CFRP. Analytical predictions shows a relatively good correlation with experimental results. In addition, in case of dynamic time-history analysis, effect of the CFRP repair intervention on shear has been evaluated. Comparative analysis reveals that a repaired member produces increased characteristics due to the repair intervention and may affect the overall response of a whole structure. Moreover, effect of shear significantly affect strength, stiffness and displacement response of the pier. In all, It is believed that the present analytical model and scheme enable a healthy evaluation of strength, stiffness and displacement capacities of a RC bridge pier being damaged and repaired.

• Physical Therapy Korea
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• v.29 no.3
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• pp.215-224
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• 2022

Background: The presence of the lumbopelvic-hip neuromuscular chain is essential for dynamic spinal stabilization; its therapeutic effects on dynamic movements of the distal extremity segment and underpinning motor mechanism remain unknown and warrant further study on participants with low back pain (LBP). Objects: We aim to compare the effects of the broken chain exercise (BCE) and connected chain exercise (CCE) on electromyography (EMG) amplitude and onset time in participants with and without LBP. Methods: Randomized controlled clinical trial. A convenience sample of 40 nonathletic participants (mean age: 24.78 ± 1.70) with and without LBP participated in this study. All participants underwent CCE for 30 minutes, 30-minute daily. We measured EMG amplitude and onset times on bilateral erector spinae (ES), gluteus maximus (GM), hamstring (HAM), transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) during the prone hip extension (PHE) test before and after the BCE and CCE. We used multivariate analysis of variance (MANOVA) to analyze the amplitude and onset time difference between exercises (BCE and CCE) and Pearson's correlations to determine any synergistic relationship among the HAM, GM, bilateral TrA/IO, and ES muscles. The statistical analyses were used at p < 0.05. Results: MANOVA showed that CCE was more decreased on EMG amplitude in HAM and bilateral ES, while increased GM and contralateral TrA/IO than BCE (p < 0.05). MANOVA EMG onset time data analyses revealed that the main effect of the conditions was significant for all HAM, GM, and bilateral ES muscles, whereas the main effect for the group was significant only for GM and contralateral ES in healthy and LBP groups. Pearson's correlation coefficient was computed to assess the relationship between BCE and CCE on dependent variables. In most of the muscles, there was a strong, positive correlation between the two variables, and there was a significant relationship (p < 0.001). Conclusion: CCE produced more effective and coordinated core stabilization and motor control mechanism in the lumbopelvic-hip muscles in participants with and without LBP during PHE than BCE.

• Archives of Pharmacal Research
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• v.12 no.2
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• pp.88-93
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• 1989

In order to obtain some informations about the effect of molecular weight on the release rate of drug from drug carrier, two types of poly-L-glutamic acid (PLGA)-cytarabine (ara-C) conjugates, PLGA-ara-C:I and PLGA-ara-C:II, were synthesized using two types of PLGA having different average molecular weight, 43,000 and 77,800, respectively. The PLGA-ara-C conjugates were synthesized by mixed anhydride method and found to be covalently linked. Both types of conjugates charged negatively at biological pH. The pH-dependent release rate of ara-C was observed in both cases, and the release rate was accelerated in basic, acidic conditions (the k values were 0.015 $day^{-1}$ at pH 7.0, 0.024 $day^{-1}$ at pH 5.0, and 0.059 $day^{-1}$ at pH 9.0 in the case of PLGA-ara-C:I) and in the presence of pretense. The time required for the release of 16.5% of ara-C from PLGA-ara-C:I were 8 hr and 144 hr in the presence and absence of protease, respectively. Although both types of conjugates showed similar drug substitution ratio, they showed different release rates. Between the two types of conjugates, PLGA-ara-C:II showed the faster release rate (0.030 vs 0.042 $day^{-1}$ in pH 7.4 phosphate buffer solution at $37^{\circ}C$) and the smaller activation energy for the release of drug (12.5 vs 7.7 Kcal/mol) than PLGA-ara-C:I. The characteristic effect of molecular weight on the release rates of PLGA-ara-C conjugates suggests that the drug release rate might be effectively controlled over a prolonged period of time by the combined use of the different types of PLGA-ara-C conjugates having different molecular weights.

• Journal of The Korean Dental Society of Anesthesiology
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• v.3 no.2 s.5
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• pp.92-97
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• 2003

Background: Gabapentin is a novel anti-epileptic drug, which is used in clinical practice to treat epilepsy. This drug is also used as an analgesic in pain patients. The antinociceptive effect of this drug was assessed using the formalin test in the rat. Methods: In order to investigate the effects of gabapentin on the trigeminal nerve territory, we injected 0.5% formalin into the upper lip. Adult, male, Sprague-Dawley rats received a $50{\mu}l$ subcutaneous injection of 5% formalin into one vibrissal pad and the consequent, facial grooming behavior was monitored. Consistent with previous investigations using tile formalin model, animals exhibited biphasic nocifensive grooming (phase 1, 0-12 min; phase 2, 12-60 min). Results: The intraperitoneal administration gabapentin 5 minutes prior to the formalin injection led to a significant, dose-dependent reduction in grooming time during phase 2. In high doses, gabapentin also reduced the time of grooming during phase 1. Conclusions: The Intraperitoneal injection of gabapentin has an analgesic effect in the facial formalin rat model and this analgesic effect increases dose-dependently.

• Geotechnical Engineering
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• v.13 no.5
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• pp.101-124
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• 1997

The root pile system is insitu soil reinforcement technique that uses a series of reticulately installed micropiles. In terms of mechanical improvement by means of grouted reinform ming elements, the root pile system is similar to the soil nailing system. The main difference between root piles and soil nailing are due to the fact that the reinforcing bars in root piles are normally grouted under high pressure and that the alignments of the reinforcing members differ. Recently, the root pile system has been broadly used to stabilize slopes and retain excavations. The accurate design of the root pile system is, however, a very difficult tass owing to geometric variety and statical indetermination, and to the difficulty in the soilfiles interaction analysis. As a result, moat of the current design methods have been heavily dependent on the experiences and approximate approach. This paper proposes a quasi-three dimensional method of analysis for the root pile system applied to the stabilization of slopes. The proposed methods of analysis include i) a technique to estimate the change in borehole radium as a function of the grout pressure as well as a function of the time when the grout pressure is applied, ii) a technique to evaluate quasi -three dimensional limit-equilibrium stability for sliding, iii) a technique to predict the stability with respect to plastic deformation of the soil between adjacent root piles, and iv) a quasi -three dimensional finite element technique to compute stresses and dis placements of the root pile structure barred on the generalized plane strain condition and composite unit cell concept talon형 with considerations of the group effect and knot effect. By using the proposed technique to estimate the change in borehole radius as a function of the grout pressure as well as a function of the time, the estimations are made and compar ed with the Kleyner 8l Krizek's experimental test results. Also by using the proposed quasi-three dimensional analytical method, analyses have been performed with the aim of pointing out the effects of various factors on the interaction behaviors of the root pile system.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.836-843
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• 2014

Obesity, a condition in which an abnormally large amount of fat is stored in adipose tissue, causing an increase in body weight, has become a major public health concern worldwide. The purpose of this study was to optimize the process for fermented milk for the production of a functional product with an anti-obesity effect by using Lactobacillus plantarum Q180 isolated from human feces. We used a 3-factor, 3-level central composite design (CCD) combined with the response surface methodology (RSM). Concentration of skim milk powder (%, $X_1$), incubation temperature ($^{\circ}C$, $X_2$), and incubation time (h, $X_3$) were used as the independent factors, whereas pH (pH, $Y_1$), anti-lipase activity (%, $Y_2$) and anti-adipogenetic activity (%, $Y_3$) were used as the dependent factors. The optimal conditions of fermented milk for the highest anti-lipase and anti-adipogenetic activity with pH 4.4 were the 9.5% of skim milk powder, $37^{\circ}C$ of incubation temperature, 28 h of incubation time. In the fermentation condition, the predicted values of pH, anti-lipase activity and anti-adipogenetic activity were 4.47, 55.55, and 20.48%, respectively. However, the actual values of pH, anti-lipase activity and anti-adipogenetic activity were 4.50, 52.86, and 19.25%, respectively. These results demonstrate that 9.5% of skim milk powder and incubation at $37^{\circ}C$ for 28 h were the optimum conditions for producing functional fermented milk with an anti-obesity effect.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.389-396
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• 2018

Marine pathogenic bacteria, such as Streptococcus parauberis, Edwardsiella tarda and Vibrio harveyi, can cause lethal infections in farmed fish, ozone and antibiotics, are employed to sterilize waters used for rearing fish to mitigate this threat. The most widely used method is treatment with sodium hypochlorite solution. However, the maintenance of a constant concentration of chlorine in rearing waters can be difficult. We investigated the potential of a mixed oxidant (MO) solution generated by electrolysis of sea water to improve water quality. We measured the survival rates of fish pathogenic bacteria exposed to different concentrations of MO (0.5, 1.0, 1.5 and 2.0 MO) and sodium hypochlorite (0.5, 1.0, 1.5 and 2.0 ppm) for various lengths of time (0, 5, 10, 15, 20, 25 and 30 min). We found a time-dependent decrease in the survival rates of the tested pathogenic microorganisms. The sterilization effect of the MO solution on pathogenic organisms was greater than that of sodium hypochlorite for gram-negative and gram-positive bacteria. We conclude that MO solution produced by electrolysis could be used to maintain a constant chlorine concentration in aquaculture systems.

• Journal of Korean Clinical Nursing Research
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• v.26 no.2
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• pp.232-239
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• 2020

Purpose: This study was an quasi-experimental study to compare the effect of applying polyethylene wrap and aircap in maintaining body temperature of preterm infants. Methods: The participants were 51 preterm infants. Aircap was applied to the experimental group (n=23) and polyethylene wrap was applied to the control group (n=28) when the preterm infants admitted to neonatal intensive care unit. The data was collected at W hospital in J-province from June 2016 to May 2017. A total of 9 body temperature measurements were taken at 3 hours interval from 5 min to 24 hours after admission. Repeated measure ANOVA, independent t-test and χ² test were conducted used with SPSS/WIN 24.0 Results: There were no significant difference in the homogeneity tests for general characteristics and dependent variables prior to the experiments (t=0.57, p=.566). There was a significant difference on body temperature of preterm infants over time (F=3.24, p=.020). There was no significant difference on body temperature between polyethylene wrap and aircap application groups (F=1.29, p=.261). The interaction between the group and the time was insignificant (F=1.51, p=.214). Conclusion: The findings demonstrated that both methods of applying polyethylene wrap and aircap on the body in preterm infants had effect in maintaining body temperature.