• KSBB Journal
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• v.23 no.5
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• pp.403-407
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• 2008

Recently, Candida antarctica lipase B (CalB) draws attention from industries for various applications for food, detergent, fine chemical, and biodiesel, because of its characteristics as an efficient biocatalyst. Since many industrial processes carry out in organic solvent and at high temperature, CalB, which is stable under harsh condition, is in demand from many industries. In order to reform CalB promptly, the expression system which has advantages of ease to use and low cost for gene libraries screening was developed using E. coli. The E. coli strains, Rosettagami with competence for enhanced disulfide bond formation, Novablue, and $DH5{\alpha}$, were exploited in this study. To obtain the soluble CalB, the pCold I vector expressing the cloned gene at $15^{\circ}C$ and the chaperone plasmids containing groES/groEL, groES/groEL/tig, tig, dnaK/dnaJ/grpE, and dnaK/dnaJ/grpE/groES/groEL were used for coexpression of CalB and chaperones. The colonies expressing functional lipase were selected by employing the halo plate containing 1% tributyrin, and the CalB expression was confirmed by SDS-PAGE. E. coli Rosettagami and $DH5{\alpha}$ harbouring groES/groEL chaperones were able to express soluble CalB effectively. From a facilitative point of view, E. coli $DH5{\alpha}$ is more suitable for further mutation study.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.3
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• pp.237-243
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• 2015

In this study, the effects of the mixing ratio of emulsified fuel on the droplet evaporation and spray behavior characteristics were analyzed. A surfactant comprising span 80 and tween 80 mixed at a 9:1 ratio was used for the emulsified fuel. The fuel and surfactant were mixed at a ratio of 3:1 for the emulsified fuel. In addition, considering the mixing ratio of the surfactant, the mixing ratio of $H_2O_2$ in the emulsified fuel was set as EF (emulsified fuel)0, EF2, EF12, EF22, EF32, and EF42. To observe the evaporation characteristics, droplets of the emulsified fuel were dropped on a heating plate and observed using scattered light and a Schlieren system. In addition, to analyze the effect of the $H_2O_2$ mixing ratio, the behavior characteristics of the evaporative free spray were investigated in the mixing ratio range of EF0 to EF22 using a constant volume chamber with heaters. Consequentially, it was found that in the case of EF22, the free spray development of the emulsified fuel was faster than that of EF0 (diesel only) because of the promotion of the evaporation due to the phase change in the peroxide contained in the emulsion fuel.

• Economic and Environmental Geology
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• v.36 no.3
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• pp.233-242
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• 2003

The southeasternmost coastal area of the Korean peninsula has been regarded as a seismologically stable area as neither Quaternary faults nor earthquake activity has been reported. To clarify whether the active tectonic movement has occurred or not, a digital marine terrace mapping and fracture mapping have been done in the coastal area. Bed rocks are composed of the Cretaceous volcanic and sedimentary rocks and the Paleogene granite. Wave-cut platform in the area is smaller and narrower relative to that of the northern coastal area. Most of the platforms in the area have little Quaternary sediment. The platforms except the Holocene terrace (1 st terrace) can be divided into three steps. The lowest platform (2nd terrace) has an altitude of 8-11 m. The broad middle one (3rd terrace) is 17 to 22 m high. The highest terrace (4th terrace) is a narrow and sporadic bench with an altitude of about 44 m high. The lowest terrace is correlated to the 2nd terrace of the northern area, which corresponds to the oxygen isotopic stage 5a. The uplift rate calculated from a graphic method is 0.19 m/ky. This low uplift is typical of an intra-plate, suggesting that the area is tectonically stable. The elevation of the platforms tends slightly lower from the north to the south in the survey area. The decreasing altitude of the platforms towards the south is interpreted to result from a local block tilting during the Latest Pleistocene. This also indicates that the eastern coast of the Korean peninsula has been suffering a subsidence to the south.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.180-188
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• 2009

This study investigated the quality of rice noodles containing different amounts of mesangi (Capsosiphon fulvescens) powder. The noodles were prepared with ratios of 1.9, 3.8, and 5.7% (w/w) of mesangi powder based on the flour weight. The noodles containing mesangi powder had lower moisture contents compared to the control, while amounts of ash were higher than in the control. For the cooking properties of the noodles, weight, volume, and turbidity were significantly higher in the mesangi rice noodles than the control (p<0.0001). The mesangi rice noodles had lower L- and a- values than the control, and these values decreased with increasing amounts of mesangi powder while the b- value increased. Texture profile analysis of the cooked noodles showed significantly higher levels of hardness (p<0.0001) and adhesiveness (p<0.05) in the mesangi rice noodles compared to the control, while cohesiveness (p<0.05), springiness (p<0.05), and gumminess (p<0.0001) values were lower than those of the control. However, the values for hardness, adhesiveness, cohesiveness, and springiness were not significantly different among the mesangi rice noodle groups. The pH of the rice noodles gradually decreased over 8 days of storage time. The 3.8% mesangi rice noodles had lower total and fungus plate counts than the other noodles during 15${\sim}$24 days of storage. However, the 3.8% masangi noodles showed the highest overall acceptability score(p<0.05).

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.2
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• pp.104-115
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• 1989

In an effort to clarify the wetted patterns of sandy loam soil under trickle irrigation conditions, the distance of wetted zone, infiltration capacity and soil wetted patterns, etc. were measured by gypsum block as soil moisture sensor located every 5 cm vertically and horizontaly in the soil bin under the such conditions as a). irrigation rates set to 2, 4, 6, 8 liters per hour b). total amount of water applied fixed to 14.62 liters per soil bin c) the hearing force of soil measured by plate penetrometer ranging from 1.04 to 1.22kg/cm$_2$ The results can be summarized as follows ; 1. The wetted distance in horizontal direction(H), the wetted distance in vertical direction(D), the horizontal infiltration capacity (iH) and the vertical infiltration capacity(in)could by explained as a function of time t. 2. The horizontal wetted distance (H) is explained by an exponetial function H= a$.$ t where b was found ranging from 021 to 026 under surface trickle irrigation, which was considered a lotlower than the classical value of 0.5 and these measurements were indifferent to the increasing irrigation rates. 3. As for the surface trickle irrigation where horizontal infiltration capacity(iH) is explained as iH = A $.$ t h, the coefficient A increases with respect to irrigation rates within the limits of 0.89~1.34. 4. In terms of surface trickle irrigation of the ratio of Dm Which is maximum vertical wetted distance to Hm, which is maximum horizontal wetted distance, found to be within range of 1.0 to 1.21. It was also noted that the value of Dm decreses when irrigation rates increases while the value of Hm changes the opposite direction. 5. The optimum location of sensors from emitter for surface trickle irrigation should he inside of hemisphere whose lateral radius is 28~30cm long and vertical radius is 10~12cm long. The distance between emitters should be within 60cm long. 6. In the study of vertical wetted distance( D) where D= a $.$ tb, the exponential coefficient b ranged from 0.61 to 0.75 in surface trickle irrigation, and from 0A9 to 0.68 for subsurface trickle irrigation. These measurements showed an increasing tendency to with respect to irrigation rates. 7. In case of vertical infiltration capacity( in), where iD= A $.$ t 1-h, the coefficient A for surface trickle irrigation found to be within range of 0.16 to 0.19 and did not show any relationships with varying degree of irrigation rates. However, the coefficient was varying from 0.09 to 0.22 and showed a tendency to increase vis-a-vis irrigation rates for subsurface trickle irrigation, in contrast. 8. In the observation of subsurface trickle irrigation, it was found that Dm/Hm ratio was within 1.52 to 1.91 and showed a decreasing tendency with respect to increasing rates of irrigation. 9. The location of sensors for subsurface trickle irrigation follows same pattern as above, with vertical distance from emitter being 10~17cm long and horizontal 22~25cm long. The location of emitter should be 50 cm. 10.The relationship between VS which is the volume of wetted soil and Q which is the total amount of water when soil is reached field capacity could be explained as VS= 2.914Q0.91and the irrigation rates showed no impacts on the above relationship.

• Journal of Animal Science and Technology
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• v.50 no.1
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• pp.133-144
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• 2008

Four different pork patties were made with two levels, HP/FP-3% and HP/FP-6%, containing 3.0 and 6.0% HP(hot air dried sweet persimmon powder)/FP(freeze-dried sweet persimmon powder), respectively. After manufacture, the meat patties were packaged with  polyvinyl wrap and stored at 4℃ for 8 days. CTL(control) and HP-3% meat patties were significantly(p<0.05) higher in moisture content than the other samples. FP-6% was found higher in protein content than the other treatments. FP-3% had a higher fat content than other meat patty samples. However, ash contents were not found significantly(p>0.05) different among the meat patty samples. The value of pH, L* and a* values were decreased as the cold storage time increased in all treatments(p<0.05). WHC(water holding capacity) of CTL and HP-6% and cooking loss of HP-3% were significantly(p<0.05) decreased with increased storage period. The diameter and thickness of all meat patties decreased with increasing the storage period. VBN(volatile basic nitrogen) values of all meat patties were increased(p<0.05) with increased storage period. TBARS (thiobarbituric acid reactive substance) of treatments were higher than that of CTL during whole storage time. The number of microorganisms(Total plate counts, Escherichia coli.) were maintained below 4.61 log10 CFU/cm2 during the whole storage period. In sensory evaluation, treatment groups had higher(p<0.05) scores in aroma, flavor, color and overall acceptability.

• Korean Journal of Head & Neck Oncology
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• v.16 no.2
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• pp.228-234
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• 2000

Objectives: Esthesioneuroblastoma is a rare malignant neoplasm that originates from the olfactory sensory cells. This tumor grows from the upper nasal cavity and ethmoid sinus and invades surrounding structures through the cribriform plate into intracranium or orbit in advanced stage. Even though there has been some controversies in determining standard treatment due to rarity of this tumor, the combination treatment of surgery and adjuvant radiation has been recommended for the locally advanced esthesioneuroblastomas. However, the recent clinical experiences of advanced cases showed that combination chemotherapy is highly effective to reduce tumor mass and improve clinical outcomes. Materials and Methods: The authors conducted a retrospective analysis of 6 esthesioneuroblastoma patients who were treated in our hospital from 1986. Results: The age of these patients was between 19 and 86 year-old. Among the 6 cases, 2 were diagnosed at stage B and 4 at stage C, according to Kadish classification. Anti-tumor treatments were performed in 5 patients. One patient refused active treatment and was lost to follow-up. Better survival outcome were observed in 3 patients who were treated with combination chemotherapy alone or combined modality treatment including chemotherapy. Conclusion: Based on our retrospective study, the combined treatment consisting of surgery, radiotherapy, and combination chemotherapy should be used to improve treatment results. And furthermore, innovative clinical approaches such as neoadjuvant chemotherapy, high-dose chemotherapy and autologous peripheral stem cell transplantation, which have been reported to have good therapeutic results, should be considered and applied actively.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.1
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• pp.39-48
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• 2008

Objective: The aim of this study was to investigate whether multipotent germline stem cells (MGSCs) can be established from neonatal mouse testis. Methods: Various cells containing MGSCs were collected from neonatal testis of ICR mice and allocated to plates for in vitro culture. After 7 days in culture, the cells were passed to a fresh culture plate and continuously cultured. From the third or fourth passage, the presumed MGSCs were cultured and maintained on mitomycin C-inactivated STO feeder cells. The MGSCs were cultured in a condition where mouse embryonic stem cells (ESCs) are cultured. Characteristics of the MGSCs were evaluated by RT-PCR, immunocytochemistry, alkaline phosphatase activity, karyotyping, and transmission electron microscopy. Results: Two MGSCs lines were established from 9 pooled sets of neonatal testicular cells. MGSCs colonies were morphologically undistinguishable from ESCs colonies and both MGSC lines as well as ESCs expressed undifferentiated stem cell markers, such as Thy-1, Oct-4, Nanog, Sox2 and alkaline phosphatase. Fine structure of undifferentiated MGSCs were similar to those of ESCs and 60% of MGSCs (12/20) had normal karyotype at passage 10. They were able to form embryoid bodies (EBs) and MGSC-derived EBs expressed marker genes of three germ layers. Conclusion: We could establish the MGSCs from neonatal mouse testis and they were differentiated to multipotent lineages of three germ layers. Molecular characteristics of MGSCs were similar to those of ESCs. Our results suggest a possibility that multipotent stem cells derived from testis, the MGSCs, could replace the ESCs in biotechnology and regenerative medicine.

• Korean Journal of Materials Research
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• v.11 no.8
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• pp.713-717
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• 2001

The magnetic and magnetostrictive properties of amorphous Tb/sub 45.7/Fe/sub 54.3-x/Co/sub x/ and Tb/sub 50.2/Fe/sub 49.8-x/Co/sub x/ (0≤x≤9.6) thin films have systematically been investigated. The films were fabricated by rf magnetron sputtering using a composite target which consists of a Fe plate and Tb, Co chips. The microstructure mainly consists of an amorphous phase. Excellent intrinsic and low magnetic-field-magnetostrictive properties were achieved in Tb/sub 45.7/Fe/sub 54.3-x/Co/sub x/ and Tb/sub 50.2/Fe/sub 49.8-x/Co/sub x/ (0≤x≤9.6). The magnetostriction of 130 ppm was obtained with low field of 100 Oe. The intrinsic magnetostriction(applied field, 5 kOe) were increased from 330ppm to 400ppm.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.382-388
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• 2015

Eleven protease-producing bacteria were isolated from the organisms' external shells and the inorganic materials collected from intertidal zone of Jeju Island, Republic of Korea. The samples were diluted serially, inoculated on Zobell agar plates with 1% skim milk and incubated at $20^{\circ}C$. Clear zone forming colonies were selected as protease-producing bacteria and each strain was identified based on the phylogenetic analysis with their 16S rDNA sequences. Strains JJM125, JJM129, YG47 and YG49 belong to the marine bacterial genus Pseudoalteromonas; strain JJM122 belong to the genus Microbulbifer; strains YG51, YG52, YG62 and YG63 belong to the genus Vibrio; and strain YG65 belong to genus Bacillus. Hence, the present study suggests that these protease producing bacteria could be further used to develop new varieties of protease with various biotechnological applications.