• Journal of the Korean Society of Safety
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• v.32 no.4
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• pp.46-52
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• 2017

Sediment exchange in river has been affected by artificial changes such as dredging and abnormal climate changes like intense rainfall. Over last decades in Korea, there were many constructions, restoration or rehabilitation in rivers. Therefore, deposition and erosion become more actively occurred than before, which may threaten the river safety such as flood defense. For safety's sake, the dredging of river bed, which is considered as the most typical measure, has been increased to extend hydraulic conveyance compared with previous conditions. However, since it might change the sediment mechanism, there would be another risk at which unexpected side effects such as headward erosion could be occurred. Particularly, sedimentation at abrupt expansion region is able to lead to hydraulic characteristics like water elevation in the upstream region in the beginning of dredging, which, however, has been barely studied in this field. Therefore in this study, the relationship between sediment mechanism at dredging section and hydraulic characteristics in upstream region were presented through numerical simulations in the idealized abruptly widen channel using Delft3D. The ideal channel of 2,000 m length with each side angle of 45 degrees at abruptly widen expansion region was employed to consider the sediment angle of repose. The sensitivity analysis was performed on the dimensionless factors consisted of upstream and downstream depths($h_u$, $h_d$), width($w_u$, $w_d$), water level(H), flow rate(Q) and discharge of sediment($Q_s$). And the sedimentation amount at dredging and the upstream hydraulic characteristics were investigated through that analysis. It showed that $h_d/h_u$, $H/h_u$ and $w_d/w_u$ were more influential in sequence of effect on sedimentation amount, while $h_d/h_u$, $w_d/w_u$ and $H/h_u$ on upstream region. It means that $h_d/h_u$ was revealed as the most significant factors on sedimentation, also it would most highly affect the rising of water level upstream.

• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.98-103
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• 2012

For screening of useful enzymes producing microorganisms from Meju, we isolated high lipase producing strains and their lipolytic enzyme activities were then tested. The lipolytic enzyme activities of isolated microorganisms were therefore tested on the Y124 strain. The gene sequence analysis of ITS from Y124 strain revealed Yarrowia lipolytica. Lipase production by the Y124 strain was studied in media containing various carbon sources. The Y124 strain drastically increased lipolytic enzyme activity in YPO media containing olive oil, as well as in YPDO media containing both olive oil and glucose. Maximal lipase production was achieved in YPD (yeast extract-peptone-D-glucose) media containing 0.7% olive oil when cultured at $30^{\circ}C$ for 8 hrs. The lipase produced from the Y124 strain showed the highest activity in p-NPO (p-nitrophenyl octanoate ($C_8$)), amongst the various p-nitrophenyl esters.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.277-290
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• 2008

The process of wound repair involves an ordered sequence of events such as overlapping biochemical and cellular events that, in the best of circumstances, result in the restoration of both the structural and functional integrity of the damaged tissue. An important event during wound healing is the contraction of newly formed connective tissues by fibroblasts. The polypeptide growth factors, like transforming growth factor-${\beta}$(TGF-${\beta}$, insulin-like growth factor I (IGF- I) and epidermal growth factor (EGF), play very important mediator roles in the process of wound contraction. Deer antlers, as models of mammalian regeneration, are cranial appendages that develop after birth as extensions of a permanent protuberance (pedicle) on the frontal bone. Antlers contain various growth factors which stimulate dermal fibroblast growth. They are involved in digestion and respiration and are necessary for normal wound healing and skin health. In order to investigate and evaluate the effects of red deer antlers on skin wound site, the speed of full-thickness skin wound healing and the expression of IGF-I, TGF-${\beta}$ and EGF in skin wounds, three groups of skin full-thickness rat models with a high concentration of antler ointment, a low concentration of antler ointment and without antler ointment were compared. At post-injury days 0, 2, 4, 8, 16, 20, 32, 40 and 60, the skin wound area was measured, the expressions of IGF-I, TGF- ${\beta}$ and EGF mRNA were detected by reverse transcriptase polymerase chain reaction (RT-PCR) and collagen formation by sirius red dye and the localization of IGF-I, TGF-${\beta}$ and EGF peptides were inspected by histological immunohistochemical techniques. Wound healing was significantly more rapid in antler treated skins. In addition, the wound treated with a high concentration antler ointment, a low concentration antler ointment, and the control closed completely at post-injury day 40, day 44 and day 60, respectively. Via RT-PCR, the expressions of IGF-I (day 8 and day 16), TGF-${\beta}$(day 8, day 16 and day 20) and EGF (day 4, day 8, day 16, and day 32) were obviously up-regulated in high concentration antler-treated skins compared to control skins. Similar results could be seen in the histological detection of collagen dye and immunohistochemical methods using the corresponding polyclone antibodies of IGF-I, TGF-${\beta}$ and EGF. These results illustrate that antlers stimulate and accelerate the repair of cutaneous wounds.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.8
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• pp.1078-1084
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• 2009

The Jindo dog is a Korean natural monument and is recognized by the Fédération Cynologique Internationale. A prominent feature is the diverse coat color within the breed. To analyze the genetic basis of variation in the Jindo coat color, we sequenced the protein-coding regions of the melanocortin 1 receptor gene (MC1R). The MC1R coding sequence was determined from 154 dogs in five breeds (Jindo, Labrador Retriever, English Springer Spaniel, Belgian Malinois, and German Shepherd). To confirm the genetic structure of sampled populations, we tested for Hardy-Weinberg equilibrium (HWE) and computed $F_{st}$ The sample populations did not significantly deviate from HWE. $F_{st}$ was 0.02 between white and fawn Jindo dogs; this was lower than $F_{st}$ between breeds. Six single nucleotide polymorphisms (SNPs) were detected in the MC1R coding region. Among the six SNPs, five were non-synonymous (S90G, T105A, Q159P, M264V, and R306ter) and one was synonymous SNP (Y298Y). From the SNPs, we predicted four haplotypes (H1, H2, H3, and H4) for Jindo MC1R. Jindo dogs had different haplotypes corresponding to different coat colors. H1 was frequently observed in white Jindo dogs with an odds ratio of 5.03 (95% CI: 2.27-11.18, p<0.0001), whereas H2 and H4 were observed only in fawn Jindo dogs. Our findings indicate that SNP haplotype can influence coat color. Knowledge of MC1R haplotypes can help discriminate white and fawn coats in Jindo dogs. We hope this report will trigger more research into the genetics of this traditional Korean dog and will be a reference for dogs of Asian origin. Also, our results will provide a useful genetic marker for Jindo dog breeders who have selected for specific colors.

• YAKHAK HOEJI
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• v.52 no.4
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• pp.299-305
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• 2008

Gabapentin, 1-(aminomethyl) cyclohexaneacetic acid, is a amino acid derivative, and is clinically effective in the treatment of neuropathic pain and partial seizures of epilepsy as a complementary therapy. The purpose of the present study was to evaluate the bioequivalence of two gabapentin tablets, $Neurontin^{R}$ tablet 800 mg (Pfizer Pharmaceuticals Co., Ltd.) and Gabapenin tablet 800 mg (Hanmi Pharm. Co., Ltd.), according to the guidelines of the Korea Food and Drug Administration (KFDA). The release of gabapentin from the two gabapentin formulations in vitro was tested using KP VIII Apparatus II method with 0.06 M HCI dissolution media. Twenty six healthy male subjects, $23.85{\pm}2.24$ years in age and $69.40{\pm}11.11$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ crossover study was employed. After a single tablet containing 800 mg as gabapentin was orally administered, blood samples were taken at predetermined time intervals and the concentrations of gabapentin in serum were determined using HPLC with fluorescence detector. The dissolution profiles of two formulations were similar in the tested dissolution media. The pharmacokinetic parameters such as $AUC_{t}$, $C_{max}$ and $T_{max}$ were calculated, and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_{t}$, $C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, $Neurontin^{R}$, were 1.28%, 0.63% and 0.62% for $AUC_{t}$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log 0.8 to log 1.25 (e.g., $log0.9097{\sim}log1.1598$ and $log0.8919{\sim}log1.1262$ for $AUC_{t}$ and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Gabapenin tablet 800 mg was bioequivalent to $Neurontin^{R}$ tablet 800 mg.

• Journal of the Korean Chemical Society
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• v.39 no.5
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• pp.364-370
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• 1995

The catalytic oxidations of several olefins in $CH_2Cl_2$ have been investigated using non-redox metalloporphyrin (M=Ga(III), In(III), Tl(III)) complexes as catalyst and sodium hypochlorite as terminal oxidant. Porphyrins were $(p-CH_3O)TPP,\;(p-CH_3)TPP,\;TPP,\;(p-F)TPP,\;(p-Cl)TPP\;and\;(F_20)TPP$ (TPP=tetraphenylporphyrin), and olefins were $(p-CH_3O)-,\;(p-CH_3)-,\;(p-H)-,\;(p-F)-,\;(p-Cl)-\;and\;(p-Br)styrene$styrene and cyclopentene and cyclohexene. The substrate conversion yield was discussed according to the substituent effects of metalloporphyrin and substrate, and the radius effect of non-redox metal ion. The conversion yield of substrate by changing the substituent of TPP increased in the order of $p-CH_3O$ < $p-CH_3$ < H < p-F < p-Cl, which was consistent with the sequence of $4{\sigma}$ values of TPP. But the substituent effect of substrate on the conversion yield decreased with increasing the ${\sigma}^+$ values on substrates in the order of p-CH3O > p-CH3 > H > p-Cl > p-Br. For the oxidation of several olefins, the complexes of In(III)- and Tl(III)-porphyrins turned out to be more active catalysts than Ga(III)-porphyrin.

• Journal of The Korean Astronomical Society
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• v.49 no.1
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• pp.25-35
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• 2016

Multiple color selection techniques are successful in identifying quasars from wide-field broadband imaging survey data. Among the quasars that have been discovered so far, however, there is a redshift gap at 5 ≲ z ≲ 5.7 due to the limitations of filter sets in previous studies. In this work, we present a new selection technique of high redshift quasars using a sequence of medium-band filters: nine filters with central wavelengths from 625 to 1025 nm and bandwidths of 50 nm. Photometry with these medium-bands traces the spectral energy distribution (SED) of a source, similar to spectroscopy with resolution R ~ 15. By conducting medium-band observations of high redshift quasars at 4.7 ≤ z ≤ 6.0 and brown dwarfs (the main contaminants in high redshift quasar selection) using the SED camera for QUasars in EArly uNiverse (SQUEAN) on the 2.1-m telescope at the McDonald Observatory, we show that these medium-band filters are superior to multi-color broad-band color section in separating high redshift quasars from brown dwarfs. In addition, we show that redshifts of high redshift quasars can be determined to an accuracy of Δz/(1 + z) = 0.002 - 0.026. The selection technique can be extended to z ~ 7, suggesting that the medium-band observation can be powerful in identifying quasars even at the re-ionization epoch.

• Journal of The Korean Astronomical Society
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• v.47 no.6
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• pp.235-253
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• 2014

Intensity interferometry, based on the Hanbury Brown-Twiss effect, is a simple and inexpensive method for optical interferometry at microarcsecond angular resolutions; its use in astronomy was abandoned in the 1970s because of low sensitivity. Motivated by recent technical developments, we argue that the sensitivity of large modern intensity interferometers can be improved by factors up to approximately 25 000, corresponding to 11 photometric magnitudes, compared to the pioneering Narrabri Stellar Interferometer. This is made possible by (i) using avalanche photodiodes (APD) as light detectors, (ii) distributing the light received from the source over multiple independent spectral channels, and (iii) use of arrays composed of multiple large light collectors. Our approach permits the construction of large (with baselines ranging from few kilometers to intercontinental distances) optical interferometers at the cost of (very) long-baseline radio interferometers. Realistic intensity interferometer designs are able to achieve limiting R-band magnitudes as good as $m_R{\approx}14$, sufficient for spatially resolved observations of main-sequence O-type stars in the Magellanic Clouds. Multi-channel intensity interferometers can address a wide variety of science cases: (i) linear radii, effective temperatures, and luminosities of stars, via direct measurements of stellar angular sizes; (ii) mass-radius relationships of compact stellar remnants, via direct measurements of the angular sizes of white dwarfs; (iii) stellar rotation, via observations of rotation flattening and surface gravity darkening; (iv) stellar convection and the interaction of stellar photospheres and magnetic fields, via observations of dark and bright starspots; (v) the structure and evolution of multiple stars, via mapping of the companion stars and of accretion flows in interacting binaries; (vi) direct measurements of interstellar distances, derived from angular diameters of stars or via the interferometric Baade-Wesselink method; (vii) the physics of gas accretion onto supermassive black holes, via resolved observations of the central engines of luminous active galactic nuclei; and (viii) calibration of amplitude interferometers by providing a sample of calibrator stars.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.1
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• pp.34-39
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• 2007

Penaeidins are members of a special family of antimicrobial peptides existing in several species of shrimp and play a crucial role in the immunological defense of shrimp. In this study, we isolated and characterized one EST clone (penaeidin) from cDNA library of fleshy prawn Fenneropenaeus chinensis hemocytes. Amino acids sequence comparison and phylogenetic analysis with other known penaeidins revealed that our clone was completely identical to F. chinensis Penaeidin 3-2 (Accession no. ABC33920), which composed of 71 amino acids with a putative signal peptide (1-19) and a cysteine-rich domain (C-terminal part). The expression and distribution of Penaeidin 3-2 transcripts in shrimp were detected in hemocytes, hepatopancreas, and muscles, and that Penaeidin 3-2 was constitutively expressed mainly in hemocytes. The artificial infection of white spot syndrome virus to F. chinensis resulted in Penaeidin 3-2 mRNA up-regulation in hemocytes, suggesting that the possible role of Penaeidin 3-2 in host defense system of F. chinensis.

• The Journal of the Acoustical Society of Korea
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• v.35 no.5
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• pp.331-339
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• 2016

This paper suggests an estimation method of the source signal and the channel impulse response (CIR) using ray-based blind deconvolution (RBD) in the underwater acoustic channel environment where Doppler effect exists by the relative motion between source and receiver. It is difficult to estimate the CIR on Doppler effect by the matched filter with a highly Doppler-sensitive waveform such as the m-sequence signal because Doppler shift can severely degrade the correlation between the received signal corrupted by Doppler effect and the original source signal. In this study, the Doppler-shifted source-signal's phase is estimated using the RBD, and the received signal is compensated by it to obtain the Doppler-corrected CIR. It is verified that using the matched filter with the received signal from the experimental data fails to estimate the CIR while the obtained CIR by the suggested method has the similarity to the propagation path of the ray model. Also, the results show that the reconstructed source signal using the RBD has the better Doppler shift compensation than the Doppler-shifted source signal derived from scattering function.