• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.3
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• pp.139-148
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• 2012

The short-term variation of salinity and temperature in a dyked estuarine environment is mainly controlled by the freshwater discharge from the dyke. We examined the distribution of salinity and temperature by the freshwater discharge in the Yeongsan River estuary using the CTD data obtained from 8 stations through three surveys in June (weak discharge) and August (intensive discharge), 2010. During the weak discharge in June, the surface salinity showed 30-32.5 psu and its horizontal gradient was relatively high around Goha-do (0.25~0.32 psu/km). On the other hand, the salinity of the bottom layer was almost constant in the range of 33 psu. Water temperature ranged $19{\sim}21^{\circ}C$ and displayed higher gradient in north-south direction than the gradient of east-west direction. During the intensive freshwater discharge on August 12, the salinity dropped to 9~26 psu. The maximum horizontal gradient of surface salinity reached 3.8 psu/km in the north of Goha-do where the strong salinity front was formed, and the horizontal salinity gradient of bottom layer was 0.28 psu/km. The horizontal gradient of water temperature was $-0.45^{\circ}C/km$ in the surface and $-0.12^{\circ}C/km$ in the bottom with high surface temperature near the dyke and decreasing gradually to the river mouth. After 3 days of the intensive discharge ($3^{rd}$ survey), the surface salinity increased to 22~26 psu. However, there still existed relatively high horizontal gradient around Goha-do. In the mean time, the bottom salinity decreased to 26.5~27.5 psu, but its gradient was not big as much as the surface gradient. According to time series of CTD profile near the dyke, the discharged fresh water jetted down temporarily and then recovered gradually with the recovering speed of 0.4 m/hour for the discharge case of $13{\times}10^6$ ton. Due to the combined effects of freshwater discharge and surface heating during the summer of 2010, the Yeongsan estuary, in general, underwent intensified vertical stratification, which in turn caused the inhibition of vertical mixing, especially inside area of estuary. Based on the spatial distribution of salinity and temperature, the Yeongsan estuary can be divided into three regions: the Goha-do area with strong horizontal gradient of salinity and temperature, inner estuary from Goha-do to the dyke with low salinity, and outer estuary from Goha-do to the coasts with relatively high salinity.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.4
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• pp.199-213
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• 2008

Saemangeum salt-water Lake has been created by the completion of the sea-dike in April 2006. To monitor the water qualities of the lake during the sea-dike construction, salinity, SS, nutrients(DIN, DIP, DISi), and chlorophyll-$\alpha$ was analyzed for the surface water from 1999 to 2007. Due to the dike construction, weaker tidal current and lesser resuspension of bottom sediment resulted in the marked decrease of the concentrations of SS in the lake water. Consequently the clearer lake water has provided better condition for primary production with deeper penetration of sunlight into the water column and sufficient nutrient content in the water. Finally the chlorophyll-$\alpha$ content became approximately double in the concentration after the dike construction. Highly stimulated algal production with the marked decrease of the concentrations of SS was decreased the concentration of DIP in the surface water. On the other hand the concentration of DIN and DISi in surface water was increased after dike construction due to the expansion of the freshwater and the supply from bottom layer. As a result, the lake revealed an extremely high NIP ratio and a DIP-limited ecosystem. The lake has been transformed from a typical coastal ecosystem to a brackish one. Since the dike completion, the lake has shown a similar change pattern to the Geum River estuary. Due to the salt-wedge intrusion of seawater, it is highly probable to expect the formation of low-oxygen zone at the bottom layer near the river-mouth area of the lake during the summer. Therefore we need a continuous sentinel monitoring of bottom water qualities in the near future.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.3
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• pp.166-178
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• 2015

We investigated marine environmental characteristics of Goheung coastal areas in August where is known to be the first outbreak site of Cochlodinium polykrikoides (hereafter C. polykrikoides) blooms, based on the oceanographic data observed from 1993 to 2013 around the Korean southern coastal waters including Eastern China Sea by National Fisheries Research and Development Institute (NFRDI). The data of NOAA/NGSST satellite images as well as numerical simulation results by Seo et al. [2013] were also used for analysis. Water temperatures at the surface and bottom layers in Goheung coast, i.e. Narodo, were $25.0^{\circ}C$ and $23.7^{\circ}C$ so that they were higher than $23.8^{\circ}C$ and $19.4^{\circ}C$ in Geoje coast where is a reference site, respectively. In addition, salinities at the surface and bottom layers in Goheung coast were 31.78 psu and 31.98 psu so that they were a little higher than 31.54 psu at the surface but a little lower than 32.79 psu at the bottom in Geoje coast, respectively. That is, the differences in water temperature or salinity between the surface and bottom layers in Goheung coast in August were not large compared to Geoje coast. This suggests that stratification in Goheung coast in August is fairly weak or may not be established. In addition, the concentrations of DIN and DIP at the surface layer were 0.068 mg/L ($4.86{\mu}M$) and 0.015 mg/L ($5.14{\mu}M$) in Goheung coast while 0.072 mg/L ($5.14{\mu}M$) and 0.01 mg/L ($0.32{\mu}M$) in Geoje coast, so they did not indicate a meaningful difference. On the other hand, when C. polykrikoides blooms, water temperature and salinity in August at the station 317-22 ($31.5^{\circ}N$, $124^{\circ}E$) of the East China Sea, where is near the mouth of Yangtze River, were $27.8^{\circ}C$ and 31.61 psu, respectively. Thus, water temperature was much higher whereas salinity was almost similar compared to Goheung coast. Furthermore, concentrations of $NO_3-N$ and $PO_4-P$ in the East China Sea in August were remarkably high compared to Goheung coast. When C. polykrikoides blooms, according to not only the image data of satellites NOAA/NGSST but also numerical experiment results by Seo et al.[2013], the freshwater out of Yangtze River was judged to clearly affect the Korean southern coastal waters. Therefore, the supply of nutrients in terms of Yangtze River may greatly contribute to the outbreak of C. polykrikoides blooms in Goheung coast in summer.

• Korean Journal of Biological Psychiatry
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• v.9 no.2
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• pp.140-151
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• 2002

Object and Method:Minor physical anomalies(MPAs) are frequently seen in patients with schizophrenia. MPAs are considered to arise from the anomalous development of ectoderm-originated tissues in the developing fetus. Since the central nervous system originates from ectoderm, MPAs can be regarded as externally observable and objective indicators of the aberrant development which might have taken place in the central nervous system. To investigate whether MPAs are more frequent in schizophrenic patients, the frequencies of MPAs were compared between schizophrenic patients and normal controls. Total 245 schizophrenic patients diagnosed with DSM-IV(male : 158, female : 87), and 418 normal control subjects(male : 216, female : 202) were included in this study. The MPAs were measured using the modified Waldrop scale with fifteen items in six bodily regions; head, eye, ear, mouth, hand, and foot. Result:The total scores of Waldrop scale were $4.40{\pm}1.93$($mean{\pm}standard$ deviation) in patients and $3.43{\pm}1.68$ in controls for females, and for males, $4.58{\pm}1.75$ in patients and $4.28{\pm}1.59$ in controls. For females, the excess of MPAs in schizophrenic patients was statistically significant(t-test : p<0.001). For males, schizophrenic patients also showed more MPAs than normal controls, but this tendency did not reach statistical significance (t-test : p=0.094). When the modified Waldrop total scores excluding head circumference were compared, the total scores in schizophrenic patients were significantly higher for both male and female subjects(t-test : male p<0.001, female p=0.001). The individual anomaly items included in Waldrop scale were also investigated. The items of epicanthus, hypertelorism, malformed ears, syndactylia were significantly more frequent in schizophrenic patients. In contrast, the items of adherent ear lobes, asymmetric ears, furrowed tongue, curved fifth finger, single palmar crease and big gap between toes did not show any differences in frequency between schizophrenic patients and normal controls. Since a lot of statistical analyses showed different results between male and female subjects, it seems to be necessary to consider gender as an important controlling variable for the analysis, however only the item of head circumference showed statistically significant gender-related difference according to log-linear analysis. Conclusion:With a relatively large sample size, the frequencies of MPAs enlisted in Waldrop scale were compared between schizophrenic patients and normal controls in this study. MPAs were more frequently seen in schizophrenic patients and, especially, several specific items in the Waldrop scale showed prominent excess in schizophrenic patients. Although definite conclusions cannot be drawn due to the inherent limitation of the study using Waldrop scale, these results seem to support the possibility that aberrant neurodevelopmental process might be involved in the pathogenesis of schizophrenia in some of the patients.

• Korean Journal of Environmental Biology
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• v.32 no.1
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• pp.35-48
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• 2014

In order to estimate the effect of additional nutrients on phytoplankton growth and horizontal phytoplankton community distribution during the autumn season in 2010 and 2011, we investigated the abiotic and biotic factors of surface and bottom waters at 20 stations of inner and offshore areas in Gwangyang Bay, Korea. Also, nutrient additional experiments were conducted to assess additional nutrient effects on phytoplankton assemblage using the surface water. In both years, the total nutrients were high at the enclosed inner bay and the mouth of Seomjin River, whereas it was low at the St.15~20 where in influenced by the surface warm water current from offshore of the bay. On the other hand, nano- and pico-sized Chl. a were gradually increased towards the outer bay and their trends were significant in 2011 than in 2010. The cryptophyta species occupied more than 85% of total phytoplankton assembleges in 2010, whereas their abundance in 2011 remainds to be 1/10 levels of 2010. Following the cryptophata species, the diatom Chaetoceros spp. and Skeletonema-like spp. were found to be dominant species. Further the biosaasy experimental results shows that the phytoplankton biomass in the +N and +NP treatments was higher compared to control and +P treatments and its trend was significant at St.8 and St.20 where nutrient concentration were low. Based on the bioassay and field survey, providing the high nutrients may have stimulated to phytoplankton growth such as S. costatum-like spp.. In particular, opportunistic micro-algae such as Cryptomonas spp. were able to achieve the high biomass under the relatively mid nutrient condition from bottom after break down of seasonal stratification in the Gwangyang Bay.

• Pediatric Infection and Vaccine
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• v.5 no.2
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• pp.267-275
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• 1998

Purpose : We have studied the changes of cardiac troponin I(cTnI) level and left ventricular ejection fraction(LVEF) before and after treatment of IVGG to evaluate the efficacy of single high dose of intravenous gammaglobulin(IVGG)(2.0gm/kg) therapy for improving cardiac function and clinical symptoms and signs in patients with clinically suspected acute myocarditis. Methods : The patients consisted of 18 cases who admitted increased cTnI with clinically suspected acute myocarditis caused by viral infection, Kawasaki disease and fever unknown origin(FUO) from Jan. 1995 to Jun. 1998. The control group consisted of 20 cases suffered from hand-foot-mouth disease, herpangina and high fever with rash. The level of cTnI was measured by Chemiluminiscent immunoassay method(normal<0.1ng/ml) and cardiac function was evaluated by left ventricular ejection fraction(LVEF)(normal 64~83%) by echocardiogram. Results : The level of cTnI increased to $0.306{\pm}0.209ng/ml$ and LVEF decreased to $60.1{\pm}1.6%$ before treatment of IVGG significantly as compared with control group(P<0.05). All cases were returned to normal range of LVEF($71.4{\pm}3.7%$) and decreased cTnI significantly($0.089{\pm}0.082ng/ml$) after treated with IVGG within 1 week in patients group(P<0.05). Conclusion : The single high dose of IVGG(2.0gm/kg) therapy was rapid and effective improvement of cardiac function and clinical symptoms and signs of acute myocarditis, and the measurement of serum cTnI and LVEF may help to diagnose and evaluate efficacy of IVGG on it.

• Journal of Aquaculture
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• v.11 no.3
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• pp.391-400
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• 1998

This study was performed to investigate the effects of environmental parameters on the growth of Pacific oyster, Crassostrea gigas at old suspended culturing grounds of Korsung Bay and newly deveoped bottom, culturing grounds of Haenam region located in southern coast of Korea. The Kosung Bay was semiclosed and water exchange occurred through the small mouth and the current speed was very slow as the value of below 0.5kn. Haenam was opened and littoral zone. Current speed of the surroundings of this Bay about to 5.0knand transparency was low with the mean depth of 1.2m by the resuspension of the sediments. Water temperature and salinity regimes were suitable for oysters at those sites, however the mean value of those parameters and seasonal fluctuations was high at Kosung. The mean concentration of dissolved oxygen in survey area was above $5.0mg/\ell$. In Kosung, however, it was decreasing in June and showed the minimum with the concentration of $4.0mg/\ell$ in August at the bottom layer and recovered in September. Eutrophication parameters such as COD were 1.44 mg/l at this location. This mean value was higher than that of the Haenam Bay's $0.96mg/\ell$. The men value of chlorophyll-$\alpha$ at Haenam was two times higher than the other sites. Growth of shell height and meat weight of oysters at Kosung Bay were higher and the fatness was lower compared to thost of Haenam. As a result, absolute growth of oysters was high at Kosung and allometric growth, such as fatness, was good at Haenam. Low water temperature and frequent exposure of oysters to the air during ebb tide may retard the shell growth. On the other hand, relatively high food availability was profitable for the fatness at haenam site.

• Korean Journal of Heritage: History & Science
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• v.44 no.4
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• pp.86-111
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• 2011

Wan is a tableware in which boiled rice or soup, side dish are put, and it is a representative model which shows the development of personal tableware. From the establishing period of Hanseong Baekje, the form of wan which is Jung-do Style(中島式) Plain Pottery of previous period Proto-Three Kingdoms Period was succeeded to, but wan is produced and used as a wan baked in the kiln, which is far development of the producing technique including hardness and clay. By and large, the size of $0.3{\sim}0.4{\ell}$ was the majority and the production technique of wan which used carefully selected soft quality clay are largely confirmed to be two methods which are, first, basic method by which on a clay tablet on the rotating table, clay band is accumulated and moulding is finished, and second, the new method which had the same basic moulding as that of basic method but in the last stage takes wan off the rotating table and reverse it to trim the bottom and remove the angle of flat bottom. The former, basic production method is the classical production method since wan of Jung-do Style Plain Pottery and wan was produced and used for all periods of Hanseong Baekje. On the other hand, the latter is the production method obtained through form imitation of China made porcelain flowed into through interchange between Baekje and China, and through comparison with Chinese chronogram material it is estimated to have been produced and used after middle of 4th century. Therefore it can be known that the Baekje people's demand for China made articles was big and imitation pottery was produced and used with Baekje pottery. In addition, bowl with outward mouth are confirmed in multiple number in Lakrang(樂浪) pottery wan and it is assumed that wan was the form produced under the influence.

• Pediatric Infection and Vaccine
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• v.23 no.1
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• pp.46-53
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• 2016

Purpose: Enterovirus (EV) infection in children can manifest various diseases from asymptomatic infection to nonspecific febrile illness, hand-foot-mouth disease, and aseptic meningitis. This study was aimed to investigate epidemiology and clinical significance of various genotypes of EV infections in pediatric inpatient. Methods: We collected the stool samples from the admitted pediatric patients in Inha University Hospital from March 2014 to March 2015. EV detection and genotype identification were performed by real-time RT-PCR and semi-nested RT-PCR. Phylogenetic trees were constructed by neighbor joining method. Results: A total of 400 samples were collected during study period and 112 patients (28%) were diagnosed with EV infections. The mean age of EV positive patients was 2.66 years (0.1-14) and sex ratio was 1.73:1. Genetic sequences of EVs were identified; coxsackievirus B5 (17, 15.2%), coxsackievirus A16 (13, 11.6%), enterovirus 71 (10, 8.9%), and coxsackievirus A2 (9, 8.0%). Nonspecific febrile illness (96, 86%) was the most common clinical manifestation and the duration of fever was 0-11 days (mean 3.1 days). Rash (44, 39%) and meningitis (43, 38%) were followed. Patients who were attending daycare center or had siblings accounted for 82.1%. Phylogenetic relationship tree revealed 6 distinct genogroups among 56 types of EVs. Conclusions: This study is the report of epidemiology, serotype distribution and clinical manifestations of children with EV infection in Incheon. This data will be helpful for further study about the epidemiology of EV infection in Korea.

• Clinical and Experimental Pediatrics
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• v.49 no.11
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• pp.1186-1193
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• 2006

Purpose : Enterovirus infection is a type of viral infection that occurs relatively frequently in children during summer. It has clinical symptoms of non-specific fever, aseptic encephalomeningitis, gastrointestinal diseases, skin rash and, hand-foot-mouth disease. However, it can also occcaisionally, result in fatal symptoms like myocarditis, epicardial inflammation, transverse myelitis, quadriplegia and etc. There have been epidemic enterovirus studies, but not in the Chungnam area. Therefore, we undertook this study in order to comprehend the cause viruses in this area. Methods: We enlisted 157 children hospitalized with enteroviral infections at Soonchunhyang University hospital in Cheonan between May and August 2005. Cerebrospinal fluids or feces were collected during the acute phase after hospitalization, and observed the cytopathic effects caused by enterovirus and using reverse transcription polymerase chain reaction (RT-PCR). Results : The number of children hospitalized due to possible enteroviral infection during the period of study was 157. The number of children who tested positive with the reverse transcription polymerase chain reaction totalled 32 cases (20.4 percent). Among the children with entroviral diseases, 20 were male and 12 were female, thus the sex ratio of male to female was 1.67:1. Their clinical symptoms included fever most frequently (93.7 percent), was followed by headaches (90.0 percent), meningeal irritation signs (65.0 percent), and abdominal pain (30.0 percent). As for the type of isolated enterovirus, there were 17 cases of echovirus 18 and 6 cases of coxsackievirus B5. Furthermore, there were 2 cases of echovirus 9, 1 case of coxsackievirus A6 and coxsackievirus B3, respectively. But 5 cases were not determined by genotype. Conclusion : Echovirus 18 is circulating in Korea. We reported on identified enteroviruses, including echovirus 18, using RT-PCR in the Chungnam area during the summer of 2005.