• Sleep Medicine and Psychophysiology
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• v.1 no.1
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• pp.47-59
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• 1994

Objectives: The main purpose of this study was to investigate the possible differences in sleepiness, performance, and body temperature during the night between morning(M) and evening(E) type subjects. Methods: After a survey study, to verify the validity and reliability of the Korean translation of the Home' and $\ddot{O}stberg's$ Morningness-Eveningness Questionnaire(1976), 8 extreme M-type subjects(3males, 5 females) and 8 extreme E-type subjects(3 males, 5 females) were selected from the university student population who had participated in the survey study. All subjects underwent sleep latency test and a battery of performance tests at intervals of 2 hours through the night, from 23:00 to 07:00. Oral temperature of each subject was taken every hour from 21 : 00 to 8 : 00. Between the testing times, the experimenters ensured that subjects remained awake. Results: More profound sleepiness was found in the M-type compared to the E-type throughout the night, with significant differences in sleepiness occuring at 23:00 and 01:00 hours. Overall performance efficiency tended to be lower through, the night in the M-type than in the E-type on all tests. A difference in time of temperature minimum between the two types was not noteworthy. Rather, there appeared to be a substantial difference in temperature level during the declining phase, with the temperature of the M-type being lower than that of the E-type. Conclusions: These results indicate the existance of a temporal relationship between sleepiness, perfonnance and body temperature during night work. Since the M-type exhibited greater sleepiness and lower performance efficiency overnight than the E-type, it may be assumed that the E-type is more suitable for and tolerable to night work. There was some discussion of the limitations in generalizing these results together with some suggestions for future studies.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.105-115
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• 2018

The comstock mealybug is one of the serious insect pest in pear. It is necessary effective control methods such as attractive sex pheromone. Using sex pheromones is necessary for studying the physiology and ecology of insect pests. In the present study, the sex pheromone of comstock mealybug was used for investigating the flying acts of the adult male. As temperature increased, the development period of eggs shortened, but it was longer at $30^{\circ}C$. The mean number of eggs laid was 482 at $25^{\circ}C$ and males constituted 37% of the experimental population at $30^{\circ}C$. The flight of the male comstock mealybug was mostly restricted to a 2-4 hour period after sunrise, even if condition of light period is changed. Male mealybugs were incapable of upwind flight towards an attractant when air velocity was 1.5 mph. Preference of height was tested in a pear orchard. The ineffective heights of the traps were 2 and 2.5 m, whereas the effective heights were 1 and 1.5 m. Many captured males at 0.5, 1, and 5 m, and the number of captured males were similar in 10, 15, and 20 m. Male mealybugs were captured up to a distance of 50 m, suggesting that it is possible to control the male mealybugs that are more than 50 m away when sex pheromone traps are used.

• The Journal of Engineering Geology
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• v.22 no.3
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• pp.253-262
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• 2012

With the aim of remediating soils contaminated by heavy metals and oil, experimental research was conducted to evaluate the optimal design factors for remediation in terms of efficient soil washing methods and processes. The experiments employed absorptiometric analysis and gas chromatography methods to reduce the concentration of heavy metals such as cooper (Cu), lead (Pb), and zinc (Zn), and total petroleum hydrocarbons (TPH) in contaminated soils. The experimental processes consisted of deciding on the washing solution, washing time, and dilution ratio for contaminated soils. A dissolution analysis of heavy metals was then performed by the addition of surfactant, based on the results of the decision experiments, and the injection processes of microbes and hydrogen peroxide were selected. The experimental results revealed that reduction effects in contaminated soils under the experimental conditions were most efficient with hydrochloric acid 0.1 mole, washing time 1 hour, and dilution ratio 1:3, individually. Additional reduction effects for heavy metals and TPH were found with the addition of a washing solution of 1% of surfactant. The addition of microbes and hydrogen peroxide caused a reduction in TPH concentration.

• Applied Microscopy
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• v.31 no.3
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• pp.267-274
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• 2001

This study was carried out to understand the effects of Saengchinyanghyoltang-gamibang (SGT) on pancreatic islets of the mice induced with streptozotocin (STZ). In the control group, two times injected with 50 mg/kg 572 at 24-hour intervals, a few number of insulin immunoreactive-cells are observed at the pancreatic islets of the mice. In the experimental group which administered with extract of SGT during 21-day, a number of immunoreactive-cells are observed at the pancreatic islets. According to the electron microscopic observation, $\beta-cells$ of the control group were contained a few of secretory granules, but also these granules were contained electro-lucent materials. In the experimental group, a lot o( secretory granules and well developed cell organelles are observed at the $\beta-cells$. The level of glucose was significantly decreased in the experimental group compared with control group, but the level of BUN was similar in these two groups. These results suggest that administration of SGT to the mice improved the damage of $\beta-cells$ from injected with STZ.

• Journal of Chest Surgery
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• v.43 no.5
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• pp.557-561
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• 2010

In the treatment of myasthenia gravis, thymectomy is generally accepted as the standard of therapy. For thymectomy, there have been various conventional open approaches including sternal splitting, but recently minimally invasive approaches have been increasingly applied. A 28-year-old man presenting with weakness of both hands and fatigability was diagnosed as having myasthenia gravis with thymic hyperplasia. He underwent a robot-assisted thymectomy with the 'da Vinci' surgical system. Through the right thoracic cavity, two thirds of the thymic gland was dissected, and the remainder was resected through the left; these procedures took, respectively, 1 hour and 30 minutes. The patient was discharged on the 8th postoperative day without complications. The minimally invasive approach with the 'da Vinci' surgical system is emerging as a popular choice and various advantages have been reported. Here we report the first successful case of robot-assisted thymectomy.

• Journal of Periodontal and Implant Science
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• v.29 no.4
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• pp.821-838
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• 1999

On the basis of the evidences that electrical stimulation could enhance proliferation and differentiation of bone cells and promote healing and regeneration of bone, this study was performed to investigate the effects of electrical stimulation on human periodontal ligament cells and gingival fibroblasts in vitro, which also have important roles in regeneration of periodontium, and to evaluate the potential of clinical application of electrical stimulation. Human periodontal ligament cells and gingival fibroblasts were primarily cultured from the root surface of extracted premolar and the adjacent gingiva without periodontal diseases. In control group, the cells ($5{\times}10^4$ cells/ml)were incubated only in Dulbecco's Modified Eagle's Medium contained with 10% fetal bovine serum. In test groups, electrical stimulation was given at the current intensity of $0.25{\mu]A$(test group 1), $1.0{\mu}A$(test group 2), and $2.5{\mu}A$(test group 3) for 12 hours to the same culture media with the control group. After 12 hour exposure of electrical stimulation, the cells were incubated for 2 and a half days(60 hours), and then each group of cells was analyzed for cell proliferation, protein level, and activity of alkaline phosphatase. The results were as follows ; 1. The Rate of cell proliferation of every test group increased significantly in both periodontal ligament cells and gingival fibroblasts, and in periodontal ligament cells, test group 3 showed significantly increased proliferation compared to the other test groups(p<0.05). 2. In the protein levels, neither periodontal ligament cell nor gingival fibroblast showed statistically significant differences between control and test groups. 3. The activity of alkaline phosphatase in periodontal ligament cells increased significantly in all test groups(p<0.05), but there were no significant differences between 3 test groups. In gingival fibroblasts, the activity of alkaline phosphatase increased significantly only in test group 3(p<0.05). From the above results, it is concluded that electrical stimulation may have beneficial effects on the regeneration of destructed periodontal tissue in regard of the stimulation of periodontal ligament cells and gingival fibroblasts as well as electrically stimulated bone formation that has been known, and that electrical stimulation may have the potential of clinical application.

• International Journal of Highway Engineering
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• v.8 no.3 s.29
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• pp.63-76
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• 2006

For a private toll road project, deciding optimal toll is an important element of economic analysis for the project and a challengeable work. In this study, the optimal toll of a private toll bridge, Geoga Bridge which connects Geoje Island of Gyeongnam Province and Gaduk Island of Busan was estimated using Stated Preference (SP) data. The SP data were collected by interviewing the passenger car drivers travelling on the National Road 14. They are latent users of the bridge. A fuzzy approximate reasoning model to estimate the optimal toll was built using the SP data. For the input variable of the model, the saved travel time and toll level were employed and the diversion rate to the bridge was employed for the output variable. The diversion rates for each toll level and saved travel time were estimated and the toll level which had maximized the toll revenue was decided as optimal toll. The optimal toll was tested by comparing with the average pay rate of passenger car drivers. Since the optimal toll for passenger cars at one hour saving, the 6,250 won is about 50 % of the average pay rate of passenger car divers, the toll was evaluated not to be high. The technique employed in this study may be used for the estimation of the optimal tolls for other kinds of vehicles.

• Korean Journal of Materials Research
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• v.14 no.12
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• pp.893-899
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• 2004

Even though Ti-6Al-4V has gained popularity as an implant material, the possible dissolution of Al and V ions in body fluids remains a matter of concern. Though commercially pure Ti (Cp-Ti) overcomes this problem, the mechanical strength of pure titanium remains very low. Thus, in this experiment Cp-Ti was processed by Equal channel angular processing (ECAP), in order to increase the mechanical strength. The biocompatibility of ECAP-Ti, Cp-Ti and Ti-6Al-4V was examined by the apatite formation on each sample surface, after treating the surface with 5M NaOH and soaking in Simulated body fluids (SBF). Initially, the samples were mechanically polished on silicone carbide paper (#2000). The polished samples were treated with 5M NaOH solution at $60^{\circ}C$ for 24 hours. The NaOH treated samples were washed gently with distill water and dried at $40^{\circ}C$ for 1 day. The dried samples were heat treated in air at $600^{\circ}C$ for 1 hour. The surface morphology of these samples were studied using SEM and XRD. The SEM studies showed network of pores in all samples. The XRD showed oxide layer formation on Cp-Ti and Ti-6Al-4V. samples. However the oxide layer in ECAP-Ti was not substantial. These samples were immersed in SBF, kept at $36.5^{\circ}C$ for seven days period. At the end of 7 days, the apatite formation was confirmed only on Cp-Ti and was not observed in Ti-6Al-4V and ECAP-Ti. These observations of apatite formation relate to the fact that Cp-Ti showed greater oxide layer than other samples. The apatite examined was confirmed as tricalcium phosphate (TCP) using EDS and XRD.

• Applied Biological Chemistry
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• v.34 no.3
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• pp.249-257
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• 1991

To elucidate enzymatic properties of ${\alpha}-galactosidase$ (EC 3, 2, 1, 22) from germinated soybean, changes in the enzyme activities and oligosaccharide contents during germination of soybean were determined. ${\alpha}-Galactosidase$ from germinated soybean was purified by ammonium sulfate fractionation, ion exchange chromatography and gel filtration. Their chemical and enzymatic properties was investigated. ${\alpha}-galactosidase$ activity of sobeam was maximized when it was germinated at $25^{\circ}C$ for 120 hour. Raffinose and stachyose in soybean were decomposed completely after 96 hours and 120 hours of germination, respectively. Soybean ${\alpha}-galactosidase$ was purified by 6.6 fold by ammonium sulfate fractionation, ion exchange chromatography on DEAE-Cellulose and Sephadex A-50, and gel filtration on Sephadex G-150. Its specific activity was 825 Units/mg protein and the yield was 2.5% of the total activity of crude extracts. The purified ${\alpha}-galactosidase$ of soybean was found to be homogeneous by polyacrylamide gel electrophoresis and by HPLC. Isoelectric point of soybean ${\alpha}-galactosidase$ was determined analytical isoelectric focusing to be pH 4.8. The soybean ${\alpha}-galactosidase$ was monomeric and its molecular weight was estimated to be 30,000 by SDS-PAGE. The optimal temperature and pH for the soybeam ${\alpha}-galactosidase$ activity were $40^{\circ}C$ and pH 6.0 and 75% of its activity was lost by heating at $60^{\circ}C$ for 10 min. The enzyme was appeared to have higher affinity to raffinose than to stachyose. The Km value of soybean enzyme was 5.3 mM for ${\rho}-nitrophenyl-{\alpha}-D-galactopyranoside$ and the activation energy on PNPG was calculated to be 13.02 Kcal per mole.

• The Journal of Korean Society for Radiation Therapy
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• v.16 no.1
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• pp.67-72
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• 2004

Purpose : Patient immobilization is crucial factor for radiation therapy. Generally, we have been used vacuum bag immobilization device(Vac-Lock) for whole body immobilization. In order to easily set up of vacuum bag(Vac-Lock), we made a 3DCA(3-Dimensional Conformal Accessary). The purpose of this study is evaluation of effectiveness of 3DCA using Vack-Lock for patient immobilization. Materials and Methods : We made 3DCA(3-Dimensional Conformal Accessary) tool of wooden boards. The reasons to choice of wooden boards are its easily handling nature and cheap expenses. Results : (1) We reduced man power from $5{\sim}6$persons to 1person to make immobilizations, (2) Shortened work time from 1hour to within 10minutes. (3) Avoid a collision to treatment gantry head. (4) Its shapes are smart and clean. Conclusion : We have made and used 3DCA(3-Dimensional Conformal Accessary) tool was very effective and convenience for the patients and users.