• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1308-1315
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• 2007

Lipase B from Candida antarctica (CalB) displayed on the cell surface of H. polymorpha has been functionally improved for catalytic activity by molecular evolution. CalB was displayed on the cell surface by fusing to a cell-wall anchor motif (CwpF). A library of CalB mutants was constructed by in vivo recombination in H. polymorpha. Several mutants with increased whole-cell CalB activity were acquired from screening seven thousand transformants. The two independent mutants CalB 10 and CalB 14 showed an approximately 5 times greater whole-cell activity than the wild-type. When these mutants were made as a soluble form, CalB 10 showed 6 times greater activity and CalB 14 showed an 11 times greater activity compared with the wild-type. Sequence analyses of mutant CALB genes revealed amino acid substitutions of $Leu^{278}Pro$ in CalB10 and $Leu^{278}Pro/Leu^{219}Gln$ in CalB14. The substituted $Pro^{278}$ in both mutants was located near the proline site of the ${\alpha}$10 helix. This mutation was assumed to induce a conformational change in the ${\alpha}$10 helix and increased the $k_{cat}$ value of mutant CalB approximately 6 times. Site-directed mutagenized CalB, LQ ($Leu^{219}Gln$) was secreted into the culture supernatant at an amount of approximately 3 times more without an increase in the CalB transcript level, compared with the wild-type.

• Journal of Korean Clinical Nursing Research
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• v.22 no.3
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• pp.285-293
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• 2016

Purpose: The purpose of this study was aimed to develop evidence-based nursing practice guideline for preventing intermittent urinary catheterization (IUC) related complications using guideline remake process. Methods: Guideline remake process was conducted according to guideline adaptation manual developed by Gu et al (2012) which consisted of three main phases and 9 modules including a total of 24 steps. Results: Newly developed IUC guideline consists of introduction, overview of intermittent catheterization, summary of recommendations, recommendations, references, and appendices. There were 50 recommendations in 5 sections including assessment, equipments, catheterization, complications management, and education/consult. Three recommendations (6%) were graded A, and five (10%) and 41 recommendations(82%) were B and C, respectively. Conclusion: The IUC remade-guideline was developed based on evidence-based nursing and therefore, this guideline is recommended to be disseminated and utilized by nurses nationwide to improve the quality of care for IUC and to decrease the IUC related complications.

• Journal of Environmental Science International
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• v.21 no.6
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• pp.739-747
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• 2012

Due to the difficulties for measuring flood discharge in the dangerous field conditions, conventional instruments with relatively low accuracy such as float still have been widely utilized for the field survey. It is also limited to use simple stage-discharge relationship for assessment of the flood discharge, since the stage-discharge relationship during the flood becomes complicated loop shape. In recent years, various non-intrusive velocity measurement techniques such as electromagnetic wave or surface images have been developed, which is quite adequate for the flood discharge measurements. However, these new non-intrusive techniques have little tested in the flood condition, though they promised efficiency and accuracy. Throughout the field observations, we evaluated the validity of these techniques by comparing discharge and velocity measurements acquired concurrently during the flood in a mountain stream. As a result, the flood discharge measurements between electromagnetic wave and surface image processing techniques showed high positive relationship, but velocities did not matched very well particularly for the high current speed more 3 m/s. Therefore, it should be noted here that special cares are required when the velocity measurements by those two different techniques are used, for instance, for the validation of the numerical models. In addition, authors assured that, for the more accurate flood discharge measurements, velocity observation as well as stage height is strongly necessary owing that the unsteady flow occurs during the flood.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.5-14
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• 1998

This study was performed to estimate interrelation between characteristics of sediment and nutrient releare from sediment in Dae-cheong lake. For the investigations, sediments were sampled in June and October 1997 at fish farms, embayment, and the main stream of Dae-cheong lake. Items for investigation are as follows; water content, weight loss on ignition(IG), porosity of sediment, Total Kjeldahl Nitrogen(TKN), content of element(H, N, C), nutrient release rate. Water content and porosity were measured to conjecture the physical trait and grain size. And weight loss on ignition was measured to determine the contents of organic substance. For the determination of nutrient release rate, $PO_4-P$ and $NH_4-N$ concentration of interstitial water and overlying water were measured. Release rate of nutrients which has direct influenced upon the water quality were 0.05-8.63mg-$P/m^2{\cdot}day$ and 4.99-36.56mg-$N/m^2{\cdot}day$. And it was found that release rate was measured higher in the 1st sampling than in the 2nd sampling. And for determination of the humus level of sediment, carbon and nitrogen content were measured by using elemental analyzer. Generally, C/N ratio is used to determine humus level of lake sediment. As a result of elemental analysis, C/N ratio was determined in the range of 7.64~11.55, so humus level of Dae-cheong lake sediment was estimated from mesohumic state to oligohumic state.

• Molecules and Cells
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• v.22 no.2
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• pp.182-188
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• 2006

Dlx5 and Osx are master regulatory proteins essential for initiating the cascade leading to osteoblast differentiation in mammals, but the mechanism of osteoblast-specific expression is not fully understood. DNA methylation at CpG sequences is involved in tissue and cell type-specific gene expression. We investigated the methylation status of Dlx5 and Osx in osteogenic and nonosteogenic cell lines by methylationspecific PCR (MSP). The CpG dinucleotides of the Dlx5 and Osx promoter regions were unmethylated in osteogenic cell lines transcribing these genes but methylated in nonosteogenic cell lines. Treatment of C2C12 cells with 5-AzadC induced dose- and timedependent expression of Dlx5 and Osx mRNA by demethylating the corresponding promoters. Furthermore the mRNAs for the osteoblast markers ALP and OC, which were undetectable in untreated cells, gradually increased after 5-AzadC treatment. In addition, BMP-2 stimulation induced Dlx5 expression by hypomethylating its promoter. These findings suggest that DNA methylation plays an important role in cell type-specific expression of Dlx5 and Osx.

• Journal of the Korean Geotechnical Society
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• v.37 no.12
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• pp.89-105
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• 2021

In this paper, feasibility study was carried out to evaluate necessity of seismic design of earth retaining structures in a deep excavation. Dynamic behavior of retaining system was analyzed using FLAC, a finite difference analysis program. It was shown that maximum bending moments of retaining walls and axial forces of supports were increased up to 98% and 87% during earthquake, respectively, compared to final excavation step, which indicates that dynamic earth pressure has a large effect on a retaining system. The stability of retaining system designed according to current design specifications was evaluated using structural forces obtained by numerical analysis, and effect of earthquake loading on structural design was analyzed.

• Journal of the Korean Wood Science and Technology
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• v.49 no.4
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• pp.371-383
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• 2021

Plant essential oils are used in products such as fragrances and cosmetics due to their individual aromatic characteristics. Currently, essential oils are not only used in cosmetics but also in pharmaceutical products with anti-bacterial, anti-viral, anti-fungal, anti-parasitic, insecticidal, anti-cancer, neuroprotective, psychophysiological, or anti-aging effects. Despite their pharmaceutical properties, some studies reported cytotoxic effects in high doses. Therefore, for pharmaceutical purposes, the margin of safety of essential oils needs to be examined. Herein, we evaluated the IC₅₀ of 10 essential oil from Korean native plants: Juniperus chinensis L. var. sargentii Henry, Citrus natsudaidai Hayata, Citrus reticulata Blanco, Citrus unshiu (Yu. Tanaka ex Swingle) Marcow, Artemisia capillaris Thunb, Aster glehnii F. Schmidt, Juniperus chinensis L, Zanthoxylum schinifolium Siebold & Zucc, Zanthoxylum piperitum (L.) D, and Cinnamomum loureirii. In addition, gene regulation of the cell-cycle gene and apoptosis marker CASP3 was examined at the IC₅₀ level. The purpose of this study was to describe the toxic concentrations of essential oils extracted from Korean native plants, thereby providing toxic concentration guidelines for inclusion in a toxicity database and in the application of plant essential oils in various fields.

• Journal of Korea Water Resources Association
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• v.45 no.9
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• pp.853-860
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• 2012

It is well-known that loop effect of the stage-discharge relationship is formulated based on many field observations especially for the sand rivers. Theoretical understandings of the loop effect for the sand rivers have been widely provided, based on the facts that it is driven by the flood wave propagation and bed form changes over the given flood period. However, very few theoretical studies or field observations associated with loop-rating curves in the gravel or rock-bed mountain streams have been attempted so far, due particularly to the difficulties in the accurate discharge measurement during the flood in such field conditions. The present paper aims to report a unique loop-rating curve measured at a gravel and rock-bed mountain stream based on the flood discharge observation acquired during the typhoon, Muifa that passed nearby Jeju Island in summer of 2011. As velocity instrumentation, a non-intrusive Surface Velocity Doppler Radar to be suitable for the flood discharge measurement was utilized, and discharges were consecutively measured for every hour. Interestingly, the authors found that the hysteresis of the loop-rating curve was adverse compared to the typical trend of the sand bed streams, which means that the discharge of the rising limb is smaller than the falling limb at the same stage. We carefully speculate that the adverse trend of the loop-rating curve in the gravel bed was caused by the bed resistance change that works differently from the sand bed case.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.3
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• pp.359-369
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• 2018

An essential measure to prevent healthcare-associated infections (HAI) is to develop a consistent system of surveillance, thereby promoting a reliable situation diagnosis to perform efficient control for the problem. Patient-to-patient transmission of pathogens within the hospital plays a substantial role in the epidemiology of HAIs. Contamination of healthcare environments commonly occurs, including facilities surfaces (e.g., bed rails, bedside tables), drinking water, cooling tower water, endoscopic instruments, food, airborne, endotoxin test, sterile test and medical equipment, with pathogenic organisms. In addition, epidemiological analysis is performed by multi locus sequence tying, pulsed-field gel electrophoresis for active surveillance. Therefore, an environmental surveillance culture test for prevention improves patient safety and blocks infection agents. Effective infection control and increased safety are possible by controlling the national infection control system. In conclusion, this study contributes to an effective infection control system through the standardization of active surveillance culture laboratory and secure expertise as infection control specialist. The primary objective of the standardization is to improve the safety of the nation's healthcare system by reducing the rates of HAIs.

• Journal of Environmental Science International
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• v.20 no.6
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• pp.783-788
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• 2011

Different from the main land of South Korea, Jeju Island has been in difficulties for measuring discharge. Due to high infiltration rate, most of streams in Jeju Island are usually in the dried state except six streams with the steady base flow, and the unique geological characteristics such as steep slope and short traveling distance of runoff have forced rainfall runoff usually to occur during very short period of time like one or two days. While discharge observations in Jeju Island have been conducted only for 16 sites with fixed electromagnetic surface velocimetry, effective analysis and validation of observed discharge data and operation of the monitoring sites still have been limited due to very few professions to maintain such jobs. This research is sponsored by Ministry of Land, Transport and Maritime Affairs to build water cycle monitoring and management system of Jeju Island. Specifically, the research focuses on optimizing discharge measurement techniques adjusted for Jeju Island, expanding the monitoring sites, and validating the existing discharge data. First of all, we attempted to conduct discharge measurements in streams with steady base flow, by utilizing various recent discharge monitoring techniques, such as ADCP, LSPIV, Magnetic Velocimetry, and Electromagnetic Wave Surface Velocimetry. ADCP has been known to be the most accurate in terms of discharge measurement compared with other techniques, thus that the discharge measurement taken by ADCP could be used as a benchmark data for validation of others. However, there are still concerns of using ADCP in flood seasons; thereby LSPIV would be able to be applied for replacing ADCP in such flooded situation in the stream. In addition, sort of practical approaches such as Magnetic Velocimetry, and Electromagnetic Wave Surface Velocimetry would also be validated, which usually measure velocity in the designated parts of stream and assume the measured velocity to be representative for whole cross-section or profile at any specified location. The result of the comparison and analysis will be used for correcting existing discharge measurement by Electromagnetic Wave Surface Velocimetry and finding the most optimized discharge techniques in the future.