• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.74-74
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• 2018

Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. This study was to develop highly polymorphic EST-SSR markers based on cross-species transferability of derived SSRs from switchgrass EST databases and characterize newly developed EST - SSRs to better understand the genetic diversity of collected 37 germplasm accessions of little millet. A total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST - SSR markers were developed based on the trials of transferability of these primers in little millet. The EST - SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. T he average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. T he polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST - SSR markers in assessing genomic relationships in little millet. T he findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.

• Journal of Environmental Science International
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• v.18 no.10
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• pp.1171-1179
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• 2009

The solitary ascidian, Halocynthia aurantium, which is commonly called the sea peach because of its coloration and general shape, is a valuable organism of benthic marine population in the northern region of the East Sea, Korea. It is seldom found at a depth of less than 10 meters and the sea peach is frequently observed in large populations between 20 and 100 meters. It appears to prefer attachment to vertical rocks faces and artificial cement blocks exposed to the currents. Mass mortality and reduction of resources in sea peach, H. aurantium, were occurred in the benthic area of the northern region of the East Sea because of the rapid fluctuation of environmental factors such as temperature and salinity due to mass rainfall in summer and going up north of a strong warm current in winter. Therefore, we examined the effects of temperature and salinity on embryonic development of fertilized eggs, tadpole larva to metamorphosis, and attachment to siphon development. Laboratory-raised larvae were studied using a two-factorial experimental design with four levels of temperature(8, 12, 16 and $20^{\circ}C$) and four levels of salinity(20, 25, 30 and 34 psu). The ascidian larvae of H. aurantium survived environmental conditions between temperature of $8{\sim}20^{\circ}C$ and salinity of 25~34 psu and exhibited positive growth at $8{\sim}16^{\circ}C$ and 30~34 psu. Fertilized eggs have not developed at lower salinity of 20 psu irrespective of temperature range tested and have showed an abnormal development at the salinity of 25 psu between higher temperatures of 20 and $24^{\circ}C$. This result suggests that temperature increase and salinity reduction depending on environmental fluctuation may have significant impacts on population variation of H. aurantium in the northern region of the East Sea.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.77-80
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• 2016

Oral squamous cell carcinoma (OSCC) is one of the ten most common causes of cancer death worldwide. Assessment of molecular changes can help detect and control lesions. The aim of this study was evaluation of salivary levels of ErbB2 and CEA in OSCC patients. In this case-control study, 27 OSCC patients and 26 healthy controls participated. After obtaining consent and filling out a questionnaire, unstimulated saliva samples were collected from people in the morning for measurement of the two markers using ELISA. Data were analyzed using Mann Whitney U test in SPSS 19 software with P<0.05 considered significant. Subjects were in the age range of 40 to 65 years. \Salivary level CEA was elevated in OSCC samples ($42.6{\pm}21.1ng/ml$) as compared to those of controls ($22.6{\pm}22.1ng/ml$) (p< 0.01), but no significant variation was noted for ErbB2 ($5.2{\pm}1.8ng/ml$ and $4.93{\pm}2.14ng/ml$, p=0.28). The role of ErbB2 as a tumor marker in patients with OSCC must still be regarded as controversial and needs further studies to clarify any significance for early detection or screening. In contrast the salivary level of CEA may find application for early detection of patients.

• Journal of Pharmaceutical Investigation
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• v.30 no.4
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• pp.247-252
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• 2000

The advantages of transdermal administration are avoiding hepatic first pass effect, minimizing inter- and intra-patient variation, maintaining steady-state plasma level to provide long-term therapy from a single dose, and allowing a rapid termination of drug input. Clenbuterol, a selective ${\beta}_2-adrenergic$ receptor stimulant, has been introduced as a potent bronchodilator for patients with bronchial asthma, chronic obstructive bronchial disease. For the development of transdermal systems containing clenbuterol, two limiting factors - long lag time and low flux - must be overcome. In this study, we attempted to select optimal formulation for preparation of clenbuterol patch using hairless mouse skin and flow-through diffusion cell. The flux of clenbuterol increased as the percent of clenbuterol dose dependently in the concentration range of 5-15%. Based on this result, we fixed the concentration of clenbuterol as 15%. The effect of various penetration enhancers on percutaneous absorption of clenbuterol through hairless mouse skin was investigated. Labrafil was the most effective enhancer, which increased the permeability of clenbuterol approximately 4-fold compared with the control without penetration enhancer. Optimal enhancer concentration was 3%. The effect of various adhesives on penetration of clenbuterol was also investigated. Among the adhesives studied, MA-31 was the most effective adhesive. Furthermore, the clenbuterol patch composed of 15% clenbuterol, 3% Labrafil and 82% MA-31, which gave most excellent penetration of drug in in vitro penetration study, maintained therapeutic plasma levels in in vivo study using S.D. rats. These studies demonstrated a good feasibility of clenbuterol administration through the intact skin using a transdermal patch, and show a possibility of the development of clenbuterol patches.

• Geomechanics and Engineering
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• v.18 no.2
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• pp.189-203
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• 2019

Brine leakage is a common phenomenon during construction facilitated by artificial freezing technique, threatening the stability of frozen wall due to the continual thawing of already frozen domain. This paper takes the frequently encountered soft clay in Wujiang District as the study object, and remolded specimens were prepared by mixing calcium chloride solutions at five levels of concentration. Both the deformation and pore water pressure of frozen specimens during thawing were investigated by two-stage loading tests. Three sections were noted from the changes in the strain rate of specimens during thawing at the first-stage load, i.e., instantaneous, attenuated, and quasi-stable sections. During the second-stage loading, the deformation of post-thawed soils is closely correlated with the dissipation of pore water pressure. Two characteristic indexes were obtained including thaw-settlement coefficient and critical water content. The critical water content increases positively with salt content. The higher water content of soil leads to a larger thaw-settlement coefficient, especially at higher salt contents, based on which an empirical equation was proposed and verified. The normalized pore water pressure during thawing was found to dissipate slower at higher salt contents, with a longer duration to stabilize. Three physical indexes were experimentally determined such as freezing point, heat conductivity and water permeability. The freezing point decreases at higher salt contents, especially as more water is involved, like the changes in heat conductivity. The water permeability maintains within the same order at the considered range of salt contents, like the development of the coefficient of consolidation. The variation of the pore volume distribution also accounts for this.

• Smart Structures and Systems
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• v.26 no.6
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• pp.681-692
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• 2020

Conventional Piezoelectric Energy Harvesters (CPEH) have been extensively studied for maximizing their electrical output through material selection, geometric and structural optimization, and adoption of efficient interface circuits. In this paper, the performance of Stepped Piezoelectric Energy Harvester (SPEH) under harmonic base excitation is studied analytically, numerically and experimentally. The motivation is to compare the energy harvesting performance of CPEH and SPEHs with the same characteristics (resonant frequency). The results of this study challenge the notion of achieving higher voltage and power output through incorporation of geometric discontinuities such as step sections in the harvester beams. A CPEH consists of substrate material with a patch of piezoelectric material bonded over it and a tip mass at the free end to tune the resonant frequency. A SPEH is designed by introducing a step section near the root of substrate beam to induce higher dynamic strain for maximizing the electrical output. The incorporation of step section reduces the stiffness and consequently, a lower tip mass is used with SPEH to match the resonant frequency to that of CPEH. Moreover, the electromechanical coupling coefficient, forcing function and damping are significantly influenced because of the inclusion of step section, which consequently affects harvester's output. Three different configurations of SPEHs characterized by the same resonant frequency as that of CPEH are designed and analyzed using linear electromechanical model and their performances are compared. The variation of strain on the harvester beams is obtained using finite element analysis. The prototypes of CPEH and SPEHs are fabricated and experimentally tested. It is shown that the power output from SPEHs is lower than the CPEH. When the prototypes with resonant frequencies in the range of 56-56.5 Hz are tested at 1 m/s2, three SPEHs generate power output of 482 μW, 424 μW and 228 μW when compared with 674 μW from CPEH. It is concluded that the advantage of increasing dynamic strain using step section is negated by increase in damping and decrease in forcing function. However, SPEHs show slightly better performance in terms of specific power and thus making them suitable for practical scenarios where the ratio of power to system mass is critical.

• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.718-724
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• 2006

The heterogeneous association behaviour of various concentration binary mixtures of mono alkyl ethers of ethylene glycol with ethyl alcohol were investigated by dielectric measurement in benzene solutions over the entire concentration range at 25 ${^{\circ}C}$. The values of static dielectric constant $\epsilon_0$ of the mixtures were measured at 1 MHz using a four terminal dielectric liquid test fixture and precision LCR meter. The high frequency limiting dielectric constant $\epsilon_\infty$ values were determined by measurement of refractive index $n_D$ ($\epsilon_\infty\;=\;n_D\;^2$). The measured values of $\epsilon_0$ and $\epsilon_\infty$ were used to evaluate the values of excess dielectric constant $\epsilon^E$, effective Kirkwood correlation factor $g^{eff}$ and corrective correlation factor $g_f$ of the binary polar mixtures to obtain qualitative and quantitative information about the H-bond complex formation. The non-linear behaviour of the observed $\epsilon_0$ values of the polar molecules and their mixtures in benzene solvent confirms the variation in the associated structures with change in polar mixture constituents concentration and also by dilution in non-polar solvents. Appearance of the maximum in $\epsilon^E$ values at different concentration of the polar mixtures suggest the formation of stable adduct complex, which depends on the molecular size of the mono alkyl ethers of ethylene glycol. Further, the observed $\epsilon^E$ < 0 also confirms the heterogeneous H-bond complex formation reduces the effective number of dipoles in these polar binary mixtures. In benzene solutions these polar molecules shows the maximum reduce in effective number of dipoles at 50 percent dilutions. But ethyl alcohol rich binary polar mixtures in benzene solvent show the maximum reduce in effective number of dipoles in benzene rich solutions.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.84-88
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• 2002

The effect of chitosan on the growth of plant pathogenic fungi was investigated. Chitosan solubilized in acetic acid showed much higher and more consistent antifungal activity than that solubilized in HCl. The antifungal activity was not significantly affected within a DA (degree of deacetylation) range of $57.3-99.2\%$ tested. Water-soluble and low molecular weight chitosan ($57.3\%$ DA) against 6 plant pathogens showed that Monosporascus canonballus and Pythium irregulare were the most susceptible to the chitosan, while Fusarium oxysporum and F. graminearum were the most resistant. At a concentration of 2.5 mg/ml, the growth of pathogens was completely inhibited except for F. oxysporum. The $MIC_50$ values varied depending on both the DA of the chitosan and the plant pathogens. A chitosan with $57.3\%$ DA exhibited the lowest $MIC_50$ (ranging <0.1-1.8 mg/ml) and that with $84.7\%$ DA the highest $MIC_50$ (ranging <0.4-4.0 mg/ml) depending on the pathogen.

• Korean Journal of Plant Taxonomy
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• v.46 no.3
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• pp.273-282
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• 2016

The establishment of a DNA barcode database at the regional scale and assessments of the utility of DNA barcodes are crucial for conservation biology and for the sustainable utilization of biological resources. Schisandraceae is a small family consisting of ca. 45 species. It contains many economically important species, such as Schisandra chinensis, which is widely used as a source in tonic beverages and in oriental medicine. In Korea, three species, S. chinensis, S. repanda, and Kadsura japonica, are distributed. We evaluated the level of variation of the DNA sequences of rbcL, matK, and the ITS regions from 13 accessions representing the distributional range of the three species. The three DNA barcode regions were easily amplified and sequenced. The minimum values of the interspecific genetic distances among S. chinensis, S. repanda, and K. japonica either separately or in combination are 4- to 23-fold higher than the maximum value of the intraspecific distance, showing that there is a clear DNA barcoding gap in the regions for Korean Schisandraceae. Phylogenetic analyses of the three DNA barcode regions, separately and simultaneously, indicate that all of the DNA barcode regions are useful for identifying a species of Schisandraceae in Korea. The distinctiveness of the three species of Schisandraceae was also supported at the species level when Chinese and Japanese populations were added. The results of this study indicate that three concatenated regions constitute the best option for DNA barcoding in Schisandraceae in Korea.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.1
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• pp.34-40
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• 2012

Purpose: The study was performed to compare patients with anatomical variations in facial asymmetry with patients in the normal range using cone-beam computed tomography (CBCT) and to take the preoperative condition into consideration in the case of a sagittal split ramus osteotomy (SSRO). Methods: The study was conducted on 46 adult patients composed of 2 subdivided groups, an asymmetry group (n=26) and a symmetry group (n=20). The asymmetry group was divided between patients with hemimandibular hyperplasia (HH, n=8) and hemimandibular elongation (HE, n=18). Using cross-sectional computed tomography images, the thickness of cancelleous bone in the buccal area of the mandible, thickness of buccal cortex in the buccal aspect of the mandible, thickness of cancellous bone in the inferior aspect of the mandible, thickness of buccal cortex in the inferior aspect of the mandible, and cross-sectional surface area of the mandible were measured. Results: In the asymmetry group, the cross-sectional area of the mandible including the inferior alveolar nerve positioned on the affected side was significantly different from the symmetry group. Thickness of cancelleous bone in the buccal aspect of the mandible, thickness of cancelleous bone in the inferior aspect of the mandible, and cross-sectional surface area of the mandible in the affected site of hemimandibular hyperplasia was significantly smaller than in the symmetry group. Conclusion: The inferior alveolar nerve runs lower and in a more buccal direction and shows a smaller cross-sectional surface of the mandible in the hemimandibular hyperplasia patients with asymmetry.