• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.1
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• pp.1-8
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• 2012

To arrange effectively artificial reefs for marine afforestation, tidal currents were analyzed by numerical experiments, and particle tracking based upon tidal currents were carried out to clarify the path of algae spore. The experiments were carried out by EFDC (Environmental Fluid Dynamics Code), and water column was vertically divided 10 layers. Tidal current patterns showed to be affected by main current at outside of study area, and circle currents of two were observed from analysis of residual currents. Particle tracking were experimented for 15 days at 2 installation places in which artificial reefs for marine afforestation would be deployed. According to the results of particle tracking experiment, particle movement at St.1 showed belt type along coastal line, and St.2 showed ellipse type at 300~500 m distant from coastal line. It suggest that artificial reefs for marine afforestation should be installed belt zone at station of St.1 and ellipse zone at St.2. Modelling algae transport was also tested to account for local dispersion of algae spore due to the suspended materials.

• Korean Journal of Environmental Agriculture
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• v.13 no.1
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• pp.10-17
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• 1994

To investigate differences with the polluted sources on Cu contents in soils and paddy rices under water pollutions, soils with the distance, the surface(0-15㎝ depth) and subsurface(15-30㎝ depth) in 1982 and 1990, and rice plants at the soil sampling sites in 1990 were separately sample at Mangyeong River area under the influence of municipal and industrial waste water from Jeonju city. Soil samples were extracted with $4M-HNO_3$ and plant samples were digested with mixture of $HNO_3$ and $HClO_4$ for analyzing Cu, Cd, Zn, Pb by atomic absorption spectrophotometry. Cu contents in soils ranged from 5.20 to 71.70 mg $kg^{-1}$. Average Cu level in 1990 was higher than that in 1982. Variation of Cu content with the distances from the source of waste water in 1990 was more regularly decreased than that in 1982. A significant correlation was observed between Cu contents in leaf sheath of rice plant and Cu, Zn and Pb contents in soils. Cu contents in soil was correlated with Zn and Pb in soil at area affected by waste water, regardless of years and soil depths. Cu contents in brown rice ranged from 0.4 to 10 mg $kg^{-1}$, and it was the lowest in parts of rice plant, and Cu content in panicle axis was 2.3 times higher than that in brown rice.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.227-234
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• 2014

Purpose: The aim of this research was to develop and evaluate natural hydroxyapatite (HA) ceramics produced from the heat treatment of pig bones. Methods: The properties of natural HA ceramics produced from pig bones were assessed in two parts. Firstly, the raw materials were characterized. A temperature of $1,200^{\circ}C$ was chosen as the calcination temperature. Fine bone powders (BPs) were produced via calcinations and a milling process. Sintered BPs were then characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and a 2-year in vitro degradability test. Secondly, an indirect cytotoxicity test was conducted on human osteoblast-like cells, MG63, treated with the BPs. Results: The average particle size of the BPs was $20{\pm}5{\mu}m$. FE-SEM showed a non-uniform distribution of the particle size. The phase obtained from XRD analysis confirmed the structure of HA. Elemental analysis using XRF detected phosphorus (P) and calcium (Ca) with the Ca/P ratio of 1.6. Functional groups examined by FTIR detected phosphate ($PO{_4}^{3-}$), hydroxyl ($OH^-$), and carbonate ($CO{_3}^{2-}$). The EDX, XRF, and FTIR analysis of BPs indicated the absence of organic compounds, which were completely removed after annealing at $1,200^{\circ}C$. The BPs were mostly stable in a simulated body fluid (SBF) solution for 2 years. An indirect cytotoxicity test on natural HA ceramics showed no threat to the cells. Conclusions: In conclusion, the sintering temperature of $1,200^{\circ}C$ affected the microstructure, phase, and biological characteristics of natural HA ceramics consisting of calcium phosphate. The Ca-P-based natural ceramics are bioactive materials with good biocompatibility; our results indicate that the prepared HA ceramics have great potential for agricultural and biological applications.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.615-624
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• 2005

The cPCR technique was used to monitor rumen fermentation and attachment of Fibrobacter succinogenes to cellulose at different pH in the in vitro culture medium. The target fragments of 16S rDNA(445 bp) were amplified from genomic DNA of F. succinogenes with specific primers and internal controls(205 bp) were constructed. Cell counts were estimated from the amounts of genomic DNA, which was calculated from cPCR results. F. succinogenes in pH 6.8 and 6.2 showed apparently higher attachment than in pH 5.8 during all incubation time. There were some difference between pH 6.8 and 6.2 in the degree of attachment, but the different was not significant (P>0.05). Cellulose degradation increased in process of incubation time and the increasing rate was higher when initial pH was higher. The pH in culture medium decreased regardless of initial pH in course of incubation time. After 24 h of incubation, medium pH was dropped by 0.24, 0.58 and 0.16 units from original medium pH 6.8, 6.2 and 5.8, respectively. More gas was produced at higher initial pH in the same manner as in cellulose degradation. In summery, Initial pH of rumen culture in vitro significantly influenced cellulose digestion, gas production, pH change and bacterial attachment. Especially, low pH(5.8) resulted in much lower bacterial attachment and fiber digestion compared to higher medium pH.

• International Journal of Highway Engineering
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• v.3 no.2 s.8
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• pp.141-147
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• 2001

Maintenance cost for managing the whole network of Expressway system in Korea increases rapidly with the increase of the total length of the system. Implementation of the Pavement Management System(PMS) is essential for efficient management of the Expressway with a limited budget. The purpose of this study is to develop the main algorithm of PMS for Korea Expressway System and to associate the algorithm with database and the Highway Geographic Information System(HGIS) recently developed. Emphasis is laid on developing the algorithm as easy as possible, so that the users can use the PMS without practical difficulty. PMS is not the decision maker, but just a supporting system for the user. The algorithm is designed in such a way that the users can modify the decision criteria if necessary. The user is the one who makes the final decision of the priority and the maintenance alternatives. The users can also inquire the current condition of the whole Expressway network in detail by association of the database and the algorithm with HGIS.

• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.1-9
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• 1999

Numerous observations revealed strong evidence of increased middle ultraviolet radiation or UV-B (280 ~ 320 nm) at the earth's surface resulting from stratospheric ozone depletion. UV is the waveband of electromagnetic radiation which is strongly absorbed by nucleic acids and proteins, thus causing damage to living systems. It has been recorded in the East Sea, Korea that solar UV-B impinging on the ocean surface penetrates seawater to significant depths. Recent researches showed that exposure to UV-B for as short as 2h at the ambient level (2.0 Wm$^{-2}$) decreased macroalgal growth and photosynthesis and destroyed photosynthetic pigments. These may suggest that UV-B could be an important environmental factor to determine algal survival and distribution. Some adaptive mechanisms to protect macroalgae from UV-damage have been found, which include photoreactivation and formation of UV-absorbing pigments. Post-illumination of visible light mitigated UV-induced damage in laminarian young sporophytes with blue the most effective waveband. The existence of UV-B absorbing pigments has been recognized in the green alga, Ulva pertusa and the red alga, Pachymeniopsis sp., which is likely to exert protective function for photosynthetic pigments inside the thalli from UV-damage. Further studies are however needed to confirm that these mechanisms are of general occurrence in seaweeds. Macroalgae together with phytoplankton are the primary producers to incorporate about 100 Gt of carbons per year, and provide half of the total biomass on the earth. UV-driven reduction in macroalgal biomass, if any, would therefore cause deleterious effects on marine ecosystem. The ultimate impacts of increasing UV-B flux due to ozone destruction are still unknown, but the impression from UV studies made so far seems to highlight the importance of setting up long-term monitoring system for us to be able to predict and detect the onset of large -scale deterioration in aquatic ecosystem.

• Journal of Veterinary Clinics
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• v.23 no.2
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• pp.190-193
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• 2006

Two weeks of therapy with intra-articular hyaluronic acid and oral caprofen failed to improve the clinical signs of hip osteoarthritis radiologically confirmed in a dog. Then, over the period of 30 days (7 sessions at 5-day intervals), bee- venom acupuncture (BV-AP, injection of bee venom at acupoints, also called apitoxin-aquapuncture) plus Trigger Point (TP) therapy was used. Five acupoints on the affected right limb were injected each time: GB30(as local point), plus ST35, GB33, BL40 and LIV08 (as distant points). The injection mixture (0.2 ml/point; total 1 ml/session) was saline + apitoxin + 2% lidocaine, so that the injected solution contained $100{\mu}g$ apitoxin diluted in 0.2% lidocaine-saline solution/ml. The total dose of apitoxin used was, therefore, $100{\mu}g/session$, divided over the 5 acupoints. One TP in the middle of the right quadriceps muscle was injected with 2% lidocaine (0.2 ml/point) each time. BV-AP improved the clinical signs rapidly; lameness and ataxia were disappear after 7 sessions (30 days); the right hind limb muscular atrophy was much improved and the hip radiograph was almost normal two weeks after 7 sessions (44 days). The present patient was a case with canine hip osteoarthritis which showed favorable therapeutic response by BV-AP plus TP therapy.

• Journal of Veterinary Clinics
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• v.27 no.3
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• pp.209-215
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• 2010

Canine coronavirus (CCV) is a cause of sporadic outbreaks of enteritis in dogs. This study was performed to carry out epidemiological investigation on the recent outbreaks of CCV enteritis of dogs and determined the potential prognostic factors affecting the survival of dogs. The 131 (34.4%) out of 381 fecal samples collected from dogs with enteritis were positive for CCV by RT-PCR. The fecal samples contained genotype I (30.5%), genotype II (29.0%), and both genotypes (40.5%) of CCV. The majority of dogs with CCV infection ranged 6-18 weeks of age. Age over 18 weeks was significantly associated with higher survival rate (P < 0.05). Of the clinical signs examined, dogs without anorexia were significantly higher survival rate (P < 0.01). The 90.1% of dogs with CCV infection were co-infected by CCV and CPV-2. From the results of this study, it can be concluded that CCV infection is widespread in the Korean dog population and CCV may be attributed to be one of the important agents causing enteritis in pups.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.3
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• pp.547-552
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• 2002

To investigate an efficacy of mixed extract with Ginseng radix, Puerariae lobata, Puerariae radix, Rubi pructus, Gomi pructus, Hoelen, Dried orange peel and Parvum comus cervi etc., on the hangover elimination, 12 hr-fasted male Sprague-Dawley rats weighing 150-200 g were given mixed extract (5 mL/kg, p.o.) and administered ethanol at a dose of 3 g/kg bw (25% in distilled water) orally 30 min postdosing. Blood was collected from caudal artery at 0.25, 0.5, 1, 2, 4, 6, 8, 10, and 12hr and then the animals were sacrificed at 24hr after the ethanol treatment. In these experiments, liver function indices, such as alanine aminotransferase and alkaline phosphatase activities, showed unaltered results in all treated groups compared with the normal group. The pharmacokinetics of ethanol after oral administration of mixed extract were also evaluated. From 0 min to 12hr, the administration of mixed extract showed 14% reduction of the area under the serum concentrations-versus-time curves (AUC) compared with the control group. The activities of alcohol dehydrogenase and aldehyde dehydrogenase measured at 24hr postdosing were also not altered by the administration of mixed extract compared with the control group. These studies demonstrate that oral administration of mixed extract, prepared by traditional prescription, decreases the ethanol concentration in serum and reduces AUC, suggesting that the mixed extract is effective for elimination of ethanol-induced hangover.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.2
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• pp.493-498
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• 2003

Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamchotang have been used in Oriental Medicine for many centuries as a treatment for various disease. The purpose of the present study is to determine the effect of Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamchotang on narepinephrine(NE) induced contraction of isolated rabbit femoral artery. Rabbits (2.0kg, female) were killed by CO₂ exposure and a segment (8-10mm) of the aortic ring from each rabbit was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 1.5g loading tension. The dose of NE which evoked 50% of maximal response (ED/sub 50/) was obtained from cumulative dose response curves for NE (10/sup -7/～10/sup -4/M). Contractions evoked by NE (ED/sub 50/) were inhibited significantly by Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamcho-tang. The mean percent inhibition of NE induced contraction was 83.9% (p<0.01) after 150㎕/㎖ Paeoniae Radix, 101.1 %(p<0.01) after 150 ㎕/㎖, Glycyrrhizae Radix and 107.3%(p<0.01) after 150㎕/㎖ Jakyakgamcho-tang, Indomethacin slightly but significantly attenuated the inhibitory effects of Paeoniae Radix. Following treatment with indomethacin, the mean percent inhibition caused by 150㎕/㎖ Paeoniae Radix fell to 16.4% in femoral artery induced by NE contraction. Propranolol, ODQ, and L-NNA did not significantly alter the inhibitory effect of Paeoniae Radix. ODQ slightly but significantly attenuated the inhibitory effects of Glycyrrhizae Radix. Following treatment with ODQ, the mean percent inhibition caused by 150㎕/㎖ Glycyrrhizae Radix fell to 13.0% in femoral artery induced by NE contraction. Propranolol, indomethacin and L-NNA did not significantly alter the inhibitory effect of Glycyrrhizae Radix. L-NNA slightly but significantly attenuated the inhibitory effects of Jakyakgamchotang. Following treatment with L-NNA, the mean percent inhibition caused by 150㎕/㎖ Jakyakgamchotang fell to 13.8% in femoral artery induced by NE contraction. Propranolol, ODQ and indomethacin did not significantly alter the inhibitory effect of Jakyakgamcho-tang. These results indicate that Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamcho-tang can relax NE induced contraction of the isolated rabbit femoral artery, and that this inhibition related to nitric oxide.