• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.35.1-35.1
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• 2017

We present the characteristics and the performance of the new CCD camera system, SNUCAM-II (Seoul National University CAMera system II) that was installed on the Lee Sang Gak Telescope (LSGT) at the Siding Spring Observatory Australia in 2016. SNUCAM-II consists of a deep depletion chip covering a wide wavelength from $0.3{\mu}m$ to $1.1{\mu}m$ with high sensitivity (QE at 90%). It is equipped with SDSS ugriz filters and 13 medium band width (50nm) filters. On LSGT, SNUCAM-II covers $15.7{\times}15.7arcmin$ FOV at pixel scale of 0.92 arcsec and a limiting magnitude of g = 19.91 AB mag at $5{\sigma}$ with 180s exposure time. SNUCAM-II will enable us to study Spectral Energy Distributions (SEDs) of diverse objects from extragalactic sources to solar objects in the southern hemisphere for research and education activities.

• Journal of Welding and Joining
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• v.23 no.2
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• pp.59-65
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• 2005

A leaky surface acoustic wave (LSAW) velocity was measured using a scanning acoustic microscope on the ceramic/metal interface in order to investigate material properties. The inverse Fourier transform (IFFT) of the V(z) curve contains the reflectance function of a liquid-specimen interface. So, the longitudinal, transverse, and Rayleigh wave velocities for each layer are obtained by the inversion of the V(z) curve at the same time. This paper contains mainly the experimental procedure for measurements of the LSAW velocity, and the results obtained for the velocity variation of individual layer after the thermal shock. It is shown that this method is useful in measuring the material properties under external stress.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.118-119
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• 2019

• Journal of Korean Neurosurgical Society
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• v.58 no.4
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• pp.346-349
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• 2015

Objective : To investigate the value of lumbar bone mineral density (BMD) in fracture risk assessment (FRAX) tool. Methods : One hundred and ten patients aged over 60 years were enrolled and divided into 2 groups as non-osteoporotic vertebral fracture (OVF) and OVF groups. The 10-year-risk of major osteoporotic vertebral fracture of each group was calculated by FRAX tool with femoral and lumbar spine BMDs to compare the usefulness of lumbar spine BMD in prediction of OVF. The blood level of osteocalcin and C-terminal telopeptide (CTX) as markers of activities of osteoblast and osteoclast, respectively were analyzed using the institutional database. Results : In the OVF group, the ratio of patients with previous fracture history or use of glucocorticoid was higher than those in non-OVF group (p=0.000 and 0.030, respectively). The levels of T-score of femur neck and lumbar spine in OVF group were significantly lower than those in non-OVF group (p=0.001 and 0.000, respectively). The risk of OVF in FRAX using femur BMD in non-OVF and OVF groups was $6.7{\pm}6.13$ and $11.4{\pm}10.06$, respectively (p=0.007). The risk of using lumbar BMD in the 2 groups was $6.9{\pm}8.91$ and $15.1{\pm}15.08$, respectively (p=0.002). The areas under the receiver operator characteristic curve in the FRAX risk with lumbar and femur neck BMD were 0.726 and 0.684, respectively. The comparison of osteocalcin and CTX was not significant (p=0.162 and 0.369, respectively). Conclusion : In our study, the 10-year risk of major osteoporotic fracture in the OVF group of our study was lower than the recommended threshold of intervention for osteoporosis. Hence, a lower threshold for the treatment of osteoporosis may be set for the Korean population to prevent OVF. In the prediction of symptomatic OVF, FRAX tool using lumbar spine BMD may be more useful than that using femur neck BMD.

• Journal of Home Health Care Nursing
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• v.10 no.1
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• pp.5-14
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• 2003

Recently, there has been an increasing need for long-term care and comprehensive health care services in community settings. The Ministry of Health and Welfare introduced the Hospital-Based Home Nursing Care Program in 2000. Before this initiative, there was a Home Nursing Demonstration Center, affiliated with the Seoul Nurse Association, had offered home nursing services with the financial support from the local government. since 1993, the Center's nursing staff has been engaged in a general hospital in an effort to provide home nursing care services within Korea's health care system. The purpose of this study was to analyze and identify characteristics of community-based home nursing care supplied by a community-based home nursing team engaged in a general hospital. Also. visit nursing care services provided by public health centers were evaluated in terms of accessibility and supply versus demand, to enhance the accessibility of low-income patients living in Seoul to home nursing care services. Data were collected from home nursing insurance reimbursement claims submitted by the community-based home nursing care team from March 1 to October 30 in 2001 and a questionnaire survey on home-visit nursing services of 25 public health centers in Seoul. The subjects consisted of 197 patients and 12 public health centers. The result were as follows. First, medical institution's community-based home nursing care program was better in technical quality than health-center-based home-visit nursing care. In addition. the pattern of the subject patients was similar to that of hospital-based home nursing care program. Second, there was a high demand for community-based home nursing care while only a small number of home-visiting nurses served at public health centers in Seoul. As a result, many patients could not receive adequate care. Finally, we suggest that community-based home nursing care program should be introduced in the national health system to meet the at-home care needs of severely ill low-income patients. Furthermore, to better utilize home nursing and visit-nursing care resources and offer continued care for patients in community settings, an efficient referral network should be built among related institutions. This would require improvement of reimbursement system and amendment of the law related to health insurance system and community-based home nursing care services.

• Applied Chemistry for Engineering
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• v.26 no.2
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• pp.165-172
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• 2015

Quercetin and its glycoside, rutin, are flavonoids, which are well known as natural antioxidants. In this study, cationic liposomes loaded with flavonoids (quercetin or rutin) were investigated for their effects on cell and skin permeability, and protective effects against UVA. The particle size of the empty cationic liposomes was in the range of 100~130 nm, and the zeta potential was + 33.05 mV. The entrapment efficiency of 0.5R/CL was higher than that of 0.5 Q/CL. The cellular uptake of the cationic liposomes was five-fold higher than that of liposomes. The skin permeability of quercetin and rutin was investigated using Franz diffusion cells. Compared to the initial loading dose, the amount of quercetin or rutin delivered to the skin by cationic liposomes was higher than that delivered by conventional liposomes or phosphate-buffered saline. From the protective effect of cationic liposomes against UVA ($25J/cm^2$), we found that the cell viability in cationic liposomes containing flavonoids was higher than that of using UVA irradiation only. These results indicate that cationic liposomes provide enhanced delivery of flavonoids (quercetin and rutin) into the skin and may be used for antiaging and antioxidant cosmetics.

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.563-568
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• 2015

Liquiritin and its aglycone, liquiritigenin are flavonoid found in licorice that show anti-oxidant and anti-aging properties. In this study, ethosomes loaded with hydrophobic liquiritigenin or liquiritin were prepared as a transdermal delivery system. The particle size, entrapment efficiency, and skin permeability of ethosomes were evaluated. Ethosome containing liquiritigenin was stable up to 2 mM and ethosome containing liquiritin was stable up to 0.75 mM concentration. The particle size of ethosomes containing 0.75 mM liquiritigenin and liquiritin was 143.85 and 158.90 nm, respectively and the entrapment efficiency was 47.51 and 54.61%, respectively. The entrapment efficiency was improved with increasing concentrations of drugs. Ethosomes loaded with liquiritigenin or liquiritin were superior in skin permeation ability compared to that of 20% ethanol solution and conventional liposomes. These results suggest that ethosomes containing 0.50 mM liquiritigenin or liquiritin are effective for the skin permeation and may be used as an antiaging and antioxidant ingredient in cosmetic formulation.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.211-218
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• 2018

Different packaging methods and storage temperatures were tested to determine the storage stability of beef dry-aged for 21 days based on microbial, physicochemical, and sensory qualities. After completion of the dry aging, the dried surface of beef sirloin was trimmed off, and the beef was packaged using two different methods (oxygen-permeable wrap or vacuum packaging) and stored at different temperatures ($3{\pm}2^{\circ}C$ or $-23{\pm}2^{\circ}C$) for 0, 7, 14, or 21 days. Lipid oxidation and the sensory quality of the dry-aged beef were not affected by the packaging method and storage temperature during storage. No microbial growth was observed over the storage period in the vacuum-packaged dry-aged beef, regardless of the storage temperature. However, dry-aged beef in the oxygen-permeable wrap packaging showed microbial spoilage with 8.82 log CFU / g at day 7 of the refrigerated storage. The vacuum-packaged dry-aged beef showed the lowest values (p < 0.05) in $a^*$ and chroma at days 14 and 21 at $3^{\circ}C$, and days 7 and 14 at $-23^{\circ}C$, respectively. Therefore, it is recommended that dry-aged beef with wrap packaging stored in refrigerated conditions should be consumed as quickly as possible due to microbial growth. For long-term storage, dry-aged beef should be frozen because freezing can extend the color stability up to day 21 of storage without adverse effects on the hygienic or meat quality aspects of dry-aged beef.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.273-278
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• 2002

Two-step fed-batch fermentations were carried out to overproduce Bacillus licheniformis maltogenic amylase (BLMA) in recombinant Escherichia coli. The first step was to increase the cell mass by controlling the feeding of a glucose solution, while the second step was designed to improve the amylase expression efficiency by supplementing organic nitrogen sources. The linear gradient feeding method was successfully adopted to maintain the glucose concentration below 0.2 g/l during the fed-batch mode, as effectively minimizing acetic acid formation. When the dissolved oxygen (DO) level became limiting, an accumulation of acetic acid and drastic decrease in specific BLMA productivity were observed. Glucose and organic nitrogen sources consisting of yeast extract and casein hydrolysate were simultaneously supplied in the pH-stat mode to further increase the specific BLMA expression efficiency. An organic nitrogen source consisting of 200 g/1 yeast extract and 100 g/1 casein hydrolysate was found to be the best among the various combinations tested. The feeding of an organic nitrogen source in the second-step fed-batch period was highly beneficial in enhancing the BLMA production. The optimized two-step fed-batch culture resulted in 78 g/l maximum dry cell mass and 443 U/ml maximum BLMA activity, corresponding to 1.5-fold increase in the dry cell mass and 3.7-fold enhancement in BLMA production, compared with the simple fed-batch fermentation.

• Genomics & Informatics
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• v.3 no.1
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• pp.15-23
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• 2005

Background MicroRNAs (miRNAs) are a class of noncoding RNAs found in various organisms such as plants and mammals. However, most of the mRNAs regulated by miRNAs are unknown. Furthermore, miRNA targets in genomes cannot be identified by standard sequence comparison since their complementarity to the target sequence is imperfect in general. In this paper, we propose a kernel-based method for the efficient prediction of miRNA targets. To help in distinguishing the false positives from potentially valid targets, we elucidate the features common in experimentally confirmed targets. Results The performance of our prediction method was evaluated by five-fold cross-validation. Our method showed 0.64 and 0.98 in sensitivity and in specificity, respectively. Also, the proposed method reduced the number of false positives by half compared with TargetScan. We investigated the effect of feature sets on the classification of miRNA targets. Finally, we predicted miRNA targets for several miRNAs in the Caenorhabditis elegans (C. elegans) 3' untranslated region (3' UTR) database. Condusions The targets predicted by the suggested method will help in validating more miRNA targets and ultimately in revealing the role of small RNAs in the regulation of genomes. Our algorithm for miRNA target site detection will be able to be improved by additional experimental­knowledge. Also, the increase of the number of confirmed targets is expected to reveal general structural features that can be used to improve their detection.