• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.2
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• pp.81-96
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• 2011

Sediment oxygen demand(SOD) and denitrification rates were measured in four major estuaries(Suncheon Bay, Seomjin river estuary, Goseong stream estuary and Masan Bay) in south coast of Korean peninsula from March of 2009 to May 2010 to estimate organic matter cleaning capacity. SOD was estimated from the temporal dissolved oxygen concentration change and isotopic pairing technique was employed to measure denitrification. Sediment oxygen demand(SOD) was ranged from -5.1 to 24.6 mmole $O_2m^{-2}d^{-1}$ and denitrification rate was ranged from 0.0 to 3.9 mmole $N_2m^{-2}d^{-1}$in the study area. SOD was the highest in Masan Bay(-2.2 to 19.2, average = 10.2 mmole $O_2m^{-2}d^{-1}$) and Suncheon, Goseong, Tae-an and Seomjin followed. Denitrification was also the highest in Masn Bay(0.0 to 3.9, average = 1.0 mmole $N_2m^{-2}d^{-1}$) and Goseong, Seomjin, Suncheon and Taean followed. The effect of benthic photosynthesis by microphytobenthos on denitrification was evident in some season of Tae-an, Seomjin, and Masn Bay. The increased oxygen level produced by photosynthesis stimulated nitrification without severe adverse effect on denitrification and, as a result, coupled nitrification and denitrification was enhanced in these areas. A difference of seasonal patterns of denitrification at each site depended on relative importance of denitrification on different nitrate source($D_w$: nitrate from water column and $D_n$: nitrated produced during nitrification). Denitrification was maximum during spring in Goseong, Suncheon and Masan Bay. On the contrary, denitrification was the highest during summer in Tae-an and Seomjin estuary.

• Pediatric Infection and Vaccine
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• v.14 no.2
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• pp.155-161
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• 2007

Purpose : We evaluated the epidemiologic characteristics of rotavirus gastroenteritis in Daejeon, Korea from January 2001 through December 2005. Methods : We retrospectively analyzed 540 medical records of children with gastroenteritis, who had been hospitalized at The Catholic University of Korea, Daejeon St. Mary's Hospital and were tested positive by rotavirus stool examinations (latex agglutination or immunechromatography). Results : The mean age was $21.8{\pm}15.3$ months (ranged from 2 months to 9 years of age) and the distribution of children were 144 cases (26.7%) in <1 year of age, 228 (42.2%) in 1 year of age, and 93 (17.2%) in 2 years of age, and the 505 children (93.5%) were less than 4 years of age. The male-to-female ratio was 1.4:1. The mean annual number of cases was 108, with a relative even occurrence in each year. Although the patients with rotaviral gastroenteritis occurred through the year, a higher rate of occurrence was seen in spring (March to May, 40.8%) and winter season (December to February, 37.9%), without significant differences in each year. Conclusion : In Daejeon, Korea, rotaviral gastroenteritis have occurred in children less than 4 years of age, with slight annual variations and similar seasonal occurrence in the recent years. The data indicate that the recent trend in peak rotavirus activity is different from that observed decades ago in Korea.

• Journal of The Korean Society of Clinical Toxicology
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• v.2 no.2
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• pp.83-89
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• 2004

Acute poisoning is one of the diseases which need the most fastest emergency measures at the very beginning. However, at present, The Korea doesn't manage the toxication all over the country, and in particular, there is no guide to medical cure paying due regard to the traits of each area. This paper focused on the issue that the necessary data in preparing the facilities for the treatment of the poisoned patients and materials for medical treatment including antidote would have to be collected, after finding the special features of the symptoms by searching the present conditions of the poisoning in small towns next to farm villages in the North area of Youngseo, Kangwon province. This study was based on the questionnaires from 111 patients who were carried into the emergency room by the poisoning in two university hospitals of the North area of Youngseo, Kangwon, for one year, 2002. Upon investigation, the patients(111) visiting emergency room by the acute poisoning during the research period was found to be 0.37 percent of all patients(30,085) visiting emergency room. Among them, the most high percentage was given in their twenties and thirties at the rate of $39.6\%$, and the ratio($40.5\%$) of the poisoned patients after their fifties was much higher than a research($10\%$) of other areas. Many poisoned patients came to their rescue in an emergency room generally in spring and in winter, from 7 a.m. to 3 p.m. Agricultural chemical of the toxic materials had a majority at a ratio of $57.7\%$, and paraquat of the agricultural chemicals was found to have a lot of toxicity by $31.7\%$. As the trace of the toxication, the oral poisoning was common by $89.2\%$, and $55.9\%$ in the case of operating gastric lavage and nasogastric irrigation, but only $14.4\%$ for prescribing antidote. The mortality of the acute poisoned patients was $17.2\%$, and the toxication by paraquat held a majority. As a result, the acute poisoning of the North area in Youngseo, Kangwon had both of the characteristics of the rural and the city, and the patients over their fifties by the population aging had more attack of the disease than other regions. Also, with the high ratio of the toxication by the agricultural chemicals, especially, the lethal agricultural chemical was used frequently. Therefore, these dangerous situations need to find the ways to cope with.

• The Journal of Internal Korean Medicine
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• v.14 no.2
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• pp.50-70
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• 1993

Clinical observation was done on 92 cases of Occlusive CVD, Cerebral hemorrhage (Subarachnoid hemorrhage) which were confirmed by Brain CT scan and observed for over 4 weeks, among the 121 cases which were more than 65 years of age. they admitted to the Dept. of Internal Medicine, Oriental Medical Hospital in Dong Guk Univ. from July 1992 to June 1993. The result were as follows; 1. In this study, Occlusive CVD was 74 cases, Cerebral hemorrhage (Subarachnoid hemorrhage was 2 cases) was 18 cases. 2. The ratio of male to female was 1.09:1. The age distribution showed the large number in the 65-69 year group(52.2%), 7th decade was 44.5% over 8th decade was 3.3% in ratio. 3. The site of Occlusive CVD was most common at MCA. the site of Cb-hemorrhage was most common at Basal ganglia. 4. The most common preceding disease was hypertension(47.8%) and the next were diabetes mellitus(14.1%), heart desease(14.1%). 5. Recurrence rate was 33.7% and 2nd attack was 20.7%, 3rd attack was 8.7%, 4th attack was 4.3% 6. Predisposing factors in Occlusive CVD were initiated usually during resting and sleeping, and that in Cb-hemorrhage were represented chiefly exercising(66.6%). 7. The smoker was 52.2%, the drinker was 32.6% in whole group. the drinker was 61.1% by the Cb-hemorrhage. 8. The ratio of the season distribution was as follow, fall 35.8%, winter 29.3%, spring 19.6%, summer 15.3%, that of the month distribution was november 15.2%. 9. Duration from on set in Occlusive CVD, 60.8% was within 5 days, that in Cb-hemorrhage, 77.8% was within 5 days. 10. Level of consciousness on attack was clear 42.2%, lethargy and mental change(dull, stupid etc.) 41.3%. The common symptoms were motor disturbance(90.2%), verbal disturbance(65.2%), headache(43.5%). 11. The physical theraphy of Occlusive CVD has been performed 75.7% in whole group and the average beginning time was 6.4 days, and that of Cb-hemorrhage has been performed 61.1% in whole group and the average beginning time was 13 days. 12. Duration of hospitalization was noted 11-20 days was 31.5%, over 21 days was 46.8%, and the average admission was 22.7 day(Occlusive CVD), 32days (Cb-hemorrhage). 13. The main complication were observed in the studies; urinary tract infection and pneumonia were noted in 6.5%, bed sore in 5.4%. 14. The ratio of systolic blood pressures in admission and discharge decreased from 58.7% to 28.3% in over 160 mmHg, that of diastolic blood pressures in admission and discharge decreased from 72.8% to 51.1% in over 90 mmHg. In 31(33.7%) of the 92 cases it showed the glucose levels of more than normal. 15. The patients have done family history of hypertension and C.V.A were 32.6% of all 16. Occlusive CVD In 83.8% and Cb-hernorrhage in 72.2% were improved 17. The herb medications were various Sunghyanggeonggisan, Sopungtang, CHunmagudeungeum were used most frequently and Gamidaebotang, Boyangwhanotang, Gagamyunjotang, Mangeumtang etc. were used as discharge.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.45-72
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• 2005

C. neoformans-associated cryptococcosis is primarily a disease of immunocompromised persons, has a world-wide distribution, and is often spread by pigeons in the urban environment. In contrast, C. gattii causes infection in normal hosts, has only been described in tropical and semi-tropical areas of the world, and has a unique niche in river gum Eucalyptus trees. Cryptococcosis is acquired through inhalation of the yeast propagules from the environment. C. gattii has been identified as the cause of an emerging infectious disease centered on Vancouver Island, British Columbia, Canada. No cases of C. gattii-disease were diagnosed prior to 1999; the current incidence rate is 36 cases per million population. A search was initiated in 2001 to find the ecological niche of this basidiomycetous yeast. C. gaftii was found in the environment in treed areas of Vancouver Island. The highest percentage of colonized-tree clusters were found around central Vancouver Island, with decreasing rates of colonization to the north and south. Climate, soil and vegetation cover of this area, called the Coastal Douglas fir biogeoclimatic zone, is unique to British Columbia and Canada. The concentration of airborne C. gattii was highest in the dry summer months, and lowest during late fall, winter, and early spring, months which have heavy rainfall. The study of the emerging colonization of this organism and subsequent cases of environmentally acquired disease will be informative in planning public health management of new routes of exposure to exotic agents in areas impacted by changing climate and land use patterns. Cryptococcosis is an infection associated with an encapsulated, basidiomycetous yeast Cryptococcus neoformans. The route of entry for this organism is through the lungs, with possible systemic spread via the circulatory system to the brain and meninges. There are four cryptococcal serogroups associated with disease in humans and animals, distinguished by capsular polysaccharide antigens. Cryptococcus neoformans: variety grubii (serotype A), variety neoformans (serotype D), and variety gattii (serotypes B and C) (Franzot et at. 1999). C. neoformans variety gattii has recently been elevated to species status, C. gattii. C. neoformans val. grubii and var. neoformans have a world-wide distribution, and are particularly associated with soil and weathered bird droppings. In contrast, C. gattii (CG) is not associated with bird excrement, is primarily found in tropical and subtropical climates, and has a restricted environmental niche associated with specific tree species. (Ellis & Pfiffer 1990) Ellis and Pfeiffer theorize that, as a basidiomycete, CG requires an association with a tree in order to become pathogenic to mammals. In Australia, CG has been found to be associated with five species of Eucalypts, Eucalyptus camaldulensis, E. tereticornis, E. blakelyi, E. gomphocephala, and E. rudis. Eucalypts, although originally native to Australia, now have a world-wide distribution. CG has been found associated with imported eucalypts in India, California, Brazil, and Egypt. In addition, in Brazil and Columbia, where eucalypts have been naturalized, native trees have been shown to harbour CG (Callejas et al. 1998; Montenegro et al. 2000). In British Columbia, Canada, since the beginning of 1999, there have been 120 confirmed cases of cryptococcal mycoses associated with CG in humans, including 4 fatalities (data from British Columbia Centre for Disease Control), and over 200 cases in animal pets in BC (data from Central Laboratory for Veterinarians). What is remarkable about the BC outbreak of C. gattii-cryptococcosis is that all of the cases have been residents of, or visitors to, a narrow area along the eastern coast of Vancouver Island, BC, from the tip of the island in the south (Victoria) to Courtenay on the north-central island as illustrated in Figure 1. Of the first 38 human cases, 58% were male with a mean age of 59.7 years (range 20 - 82): 36 cases (95%) were Caucasian. Ten cases (26%) presented with meningitis, the remainder presented with respiratory symptoms. Cultures recovered from cases of cryptococcosis associated with the outbreak were typed as serogroup B, which is specific to CG (Bartlett et al. 2003). This was the first reported outbreak of CVG in Canada, or indeed, the world. Where infection with CG is endemic, for example, Australia, the incidence of cryptococcosis ranges from 1.8 - 4.7 per million between the southern and northern states (Sorrell 2001). However, the overall incidence of cryptococcosis in immunocompenent individuals has been estimated at 0.2 per million population per year (Kwon-Chung et al. 1984). The population of Vancouver Island is approximately 720,000,consequently, even if the organism were endemic, one would expect a maximum of 0.15 cases of cryptococcal disease annually.

• Pediatric Infection and Vaccine
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• v.10 no.1
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• pp.81-86
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• 2003

Purpose : Streptococcus pneumoniae remains a leading cause of meningitis, sepsis, pneumonia, and otitis media in children worldwide. Emergence of drug-resistant organism has substantially complicated the therapy of these infections. This study was conducted to determine the clinical features and changing patterns of antibiotic-resistant rates of Streptococcus pneumoniae. Methods : We have retrospectively examined 306 cases of culture proven patients who were admitted to the Department of Pediatrics, Severance hospital, from the year 1991 to year 2000. The type of culture specimen used, presence of penicillin resistance, characteristics according to various presenting diseases and their prevailing year were also examined. Results : The mean age of cases was 7.9 year and the ratio of male to female was 1.6 : 1. The main age group of pneumococcal infection was under 2 years(42%). Systemic infections associated with pneumococci were sepsis(19.3%) and meningitis(9.5%), while local infections presented as pneumonia(29.2%), otitis media(19.3%), exudative tonsillitis(13.3%), and sinusitis(9.2%) in the order of frequency. Seasonal variation was seen in the incidence of pneumococcal infection: high incidence of infection was seen in Spring(Mar.~Apr; 32%), while the incidence was low during summer(Aug.~Sep.; 6%). Penicillin-resistant rate of pneumococci was steadily on the increase since the year 1991(65%) to year 2000(84%). Conclusion : Antibiotic-resistant pneumococci increased during the past decade. For effective prevention of pneumococcal infections, national survey of pneumococcal infections and expanded use of pneumococcal vaccination would be needed.

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.112-120
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• 1993

The use of fertilizer N is essential for maximum economic yield of crops. Meanwhile, enrichment of $NO_3^-$in the environment has to be avoided. Winter barley crop has a short duration of growth before winter, but is used to receive N greater than 60 kg/ha at seeding. Experiments were performed to determine the quantitative aspect of the fate of soil applied urea N among the residual, leached, and uptaken by winter barley (cv. Olbori), and to evaluate the effect of soil temperature on nitrification. Four levels of urea (0, 40, 80, and 120 kg N/ha) was basal-dressed to Olbori. $NH_4^+$ appeared dominant in the soil until 40 days after seeding, whereas $NO_3^-$ did thereafter. Nitrification rate at $5^{\circ}C$ of soil temperature was 40 to 50% of that at $15^{\circ}C. Linear increases in the number of ammonia oxidizing and nitrite oxidizing bacteria of the soil was present as the level of urea fertilization was higher. Less than 60% of N applied at seeding was uptaken by winter barley until mid-March but 50% was lost from death of older barley leaves during overwintering. Thereby only 10% of the applied N remained in the barley in spring. Only 15% of the applied N was present in the rhizosphere. The 17 to 20% of the soil applied N leached out as $NO_3^-$ the rhizosphere. Nitrogen leaching during winter was estimated to be 16 and 20 kg/ha when the basal application level of urea fertilization was 80 and 120 kg/ha, respectively.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.2
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• pp.93-101
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• 2007

In order for bioremediate the benthic layer in polluted inner Bay, the effects of irradiance and wave-length irradiated from light emission diode (LED) on the growth of benthic diatom Nitzschia sp. (Hakozaki Bay strain of Japan) were investigated. The Nitzschia sp. was cultured under blue LED (450 nm), yellow LED (590 nm), red LED (650 nm) and fluorescent lamp (mixed wavelengths). At $25^{\circ}C$ and 30 psu, the growth of Nitzschia sp. showed its peak at $20\;{\mu}mol\;m^{-2}\;s^{-1}$ (blue LED) and $40\;{\mu}mol\;m^{-2}\;s^{-1}$ (fluorescent lamp), and was inhibited at the irradiance higher than that irradiance. Nitzschia sp. in yellow LED and red LED is fitted by a rectangular hyperbolic curve because no photoinhibition was observed under maximum irradiance used in this study. The irradiance-growth curves were described as ${\mu}=-0.46{\exp}(1-I/6.32)+0.46-0.00043I,\;(r^2=0.98)$ under blue LED, ${\mu}=0.42(I+7.87)/(I+58.9),\;(r^2=0.99)$ under yellow LED, ${\mu}=0.39(I+3.39)/(I+21.6),\;(r^2=0.94)$ under red LED, ${\mu}=-0.38{\exp}(1-I/7.23)+0.38-0.00016I,\;(r^2=0.96)$ under fluorescent lamp. Maximum specific growth rate of blue LED, yellow LED, red LED and fluorescent lamp was $0.44\;day^{-1},\;0.42\;day^{-1},\;0.39\;day^{-1}$ and $0.37\;day^{-1}$, respectively. The absorption coefficient ($a_{ph}$) of Nitzschia sp. was similar under all the wavelengths (400 nm-700 nm), although maximum $a_{ph}$ was $0.0224\;m^2\;mg\;chi.\;{\alpha}^{-1}$ in 472 nm and $0.0179\;m^2\;mg\;chi.\;{\alpha}^{-1}$) in 663 nm. The results may indicate the possibility of environmental improvement around the benthic layer in polluted coastal area because microphytobenthos growth is stimulated by means of irradiated blue LED at the benthic boundary layer during both autumn and winter, and yellow LED, which might have been suppressed growth of harmful algae, at the layer during both spring and summer.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.2
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• pp.129-139
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• 2002

Fish distribution characteristics are essential to assess and estimate fisheries resources in a particular area. The primary goal of this study is to determine the distribution characteristics by the bottom trawling in the Yellow Sea west of South Korea. The surveys were carried out between 33$^{\circ}$00'N~37$^{\circ}$00'N latitude and 124$^{\circ}$00'E~126$^{\circ}$00'E longitude at EEZ(Exclusive Economic Zone) of Korea in Yellow Sea on May and August, 1999 and April, 2000. The ships used in this survey were the R/V Chung-kyeong(G/T 300) and R/V Dong-baek(G/T 1,050) of Yeosu National University. The results obtained can be summarized as follows 1. From the trawl data the fisheries resources are seriously decreasing through most of the species(about more 50%) have been appeared only one time at the bottom trawl on April, 2000. The total fish species caught by the trawl net during the 3 times survey were 106 species and a few species(dominant species) of these occupied 50~90% of the quantity of the total quantity by number or by weight. Among the dominant species the tanaka's snailfish was recorded to be the most dominant species in the survey area. The fish species in the Yellow Sea were clustered according to the regions. They clustered in two or three partes to the south-north direction in the spring season and clustered in two parts to the on-off shore direction of the shore in the summer season. Most of the fish caught at the the trawl net with cover-net(30.3mm) were small sized. They were shorter than 15 cm in length and the extruding rate of the cod-end which was 60mm mesh size ranges about 90%. 2. The densities of the number and weight per unit volume derived from the total catches sampled in April, 2000 survey were $1532.2{\times}10^{-6}fish/m^3$ and $39.55{\times}10^{-6}kg/m^3$, respectively. 3. The density variation of fish population between 1999 and 2000 showed a slight tendency to increase.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.978-988
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• 2005

A three-dimensional dynamic model was applied to Lake Paldang, Han River in this study. The model was calibrated and verified using the data measured under different ambient conditions. The model results were in reasonable agreements with the field measurements in both calibration and verification. Utilizing the validated model, we analyzed the spatial and temporal distributions of temperature, current, residence time, and spreading pattern of incoming flows within the lake. Relatively low velocity and high temperature were computed at the surface layer in the southern region of the Sonae island. The longest residence time within the lake was predicted in the southern region of the Sonae island and the downstream region of the South Branch. This can be attributed to the fact that the back currents caused by the dam blocking occur mainly in these regions. Vertical thermal profiles indicated that the thermal stratifications would be occurred feebly in early summer and winter. During early spring and fall, it appeared that there would be no discernible differences at the vertical temperature profiles in the entire lake. The vertical overturns, however, do not occur during these periods due to an influence of high discharge flows from the dam. During midsummer monsoon season with high precipitation, the thermal stratification was disrupted by high incoming flow rates and discharges from the dam and very short residence time was resulted in the entire lake. In this circulation patterns, the plume of the Kyoungan stream with smallest flow rate and higher water temperature tends to travel downstream horizontally along the eastern shore of the south island and vertically at the top surface layer. The model results suggest that the Paldang lake should be a highly hydrodynamic water body with large spatial and temporal variations.