• Archives of Plastic Surgery
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• v.36 no.1
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• pp.89-92
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• 2009

Purpose: The clinical syndrome of unilateral finger ischemia, caused by digital artery occlusions from embolization from the palmar ulnar artery associated with repetitive striking of the palm, has been called the hypothenar hammer syndrome (HHS). We report the case of a man with this unique disease probably caused by manual work. Methods: A 52 - year - old male left - hand dominant manual worker complained of pain and coldness in the left 4,5th finger. On physical examination, there was a tip necrosis and the result of Allen's test was mildly positive(sluggish filling of hand from the ulnar artery). Arteriograms confirmed occlusion of the distal ulnar artery without direct perfusion of the superficial palmar arch and distal digital artery. Surgical bypass with reverse autologous vein grafting was performed between ulnar artery and superficial palmar arch, common digital artery. Results: He had an uneventful postoperative course and has remained asymptomatic for 18 months since discharge. Patency has been confirmed by color doppler with resolution of cold intolerance and successful digital preservation. Conclusion: We introduce very unique pattern of vascular ischemic disease and recommend the arterial bypass with vein interpositional grafting.

• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.71-77
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• 1999

Phytoplankton communities were investigated 13 times during the period from November, 1995 to December, 1996 in the coastal area of Kori. A total of 162 taxa (including unidentified species) were observed； 120 diatoms, 3 silicoflagellates, 34 dinoflagellates, 2 euglenoids, 1 chlorophyte and 2 unidentified microflagellates. A diatom species, Skeletonema costatum (Greville) Clove dominated all the year round. The standing stocks of phytoplankton ranged from 94 cells/ml in August to 1059 cells/ml in July. The peaks of standing stocks occurred in February and July. The effects of thermal effluent to the phytoplankton communities changed seasonally and might affect increasing the standing stocks where about 1 ∼ 3 km from the discharge of Kori Nuclear Power Plant in autumn and winter. But the effects of thermal effluent must be negative in summer.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.3
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• pp.325-335
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• 2015

Concerns about water quality in the Nakdong River have been raised because the Nakdong River will change from a lotic environment to a lentic environmental due to the installation of eight weirs to be constructed as part of the Four Major Rivers Restoration Project. The rapid urbanization and industrialization of the middle and the lower reaches of Nakdong River causes the indiscreet discharge of uncleanly living sewage and industrial wastewater. And the water quality of lower reaches of Nakdong River is getting seriously worse. Owing to the water shortage of Nakdong River and the closing of reaches because of the estuary dyke in the dry season, the velocity of a moving fluid is almost accumulated under 0.03m/sec. Then a pollutant is piled up on the bottom of the river. Polluted sediment is formed and nutrition level of water is increased more and more. The eutrophication state propagated to dark brown or green from eutrophication often comes out. Therefore in this study, we measured Chl. a of chlorophyll sensor (YSI6600V2) and aceton extraction through field observation in the Nakdong River and Samrangjin. And we evaluated the reliability of chlorophyll sensor. In correlation analysis between chlorophyll sensor and aceton extraction, it shows high relation in general. And it also shows high relation among the chlorophyll sensor and aceton extraction of the dominant diatom (Skeletonema costatum), Dinophyta (Prorocentrum minimum) in the Nakdong River estuary by laboratory analysis results.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.1
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• pp.14-23
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• 2001

The characteristics of tidal circulation with Hyungsan River discharges in Youngil Bay by the numerical experiments is elucidated. For the simulation of tidal residual currents related to inflow by the river discharges in Youngil Bay located in the southeastern part of Korean Peninsula, the two-dimensional numerical experiment is peformed. The tidal elevation boundary conditions of the 4 main tidal harmonic constituents (M₂, S₂, K₁ and O₁) on the open boundary and river discharges at the river boundary are considered. The computed results obtained from numerical experiment showed good agreements with the field observation ones. The residual currents generally flow toward the inner bay through the western (Dalman-Gap) and central areas of the bay, and then the currents go toward the outer bay along the eastern shore (Changgi-Gap) of the bay with anti-clockwise circulation. Especially, in the numerical experiment without Hyungsan River discharges, these flow patterns are disappeared. Based on the results, it showed that the Hyungsan River discharges play the dominant role in the patterns of tidal residual currents. This flow pattern of tidal residual currents are important mechanism of water quality, material transport in Youngil Bay.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.4
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• pp.485-489
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• 2008

Basal cell nevus syndrome is a hereditary disease of an autosomal dominant trait with variable conditions such as basal cell carcinomas of the skin, deformity of rib, fusion of vertebrae, mental retardation, hypertelorism, and multiple odontogenic keratocysts. A 32 years old man with pus discharge from fistula on the vestibule of left upper 1st molar visited to Chosun University Dental Hospital. Radiographic evaluation revealed multiple maxillary and mandibular cysts that had multilocular radiolucency on left mandibular body area, thining of inferior border of left border of ramus and well defined unilocular radiolucency above right upper 1st and 2nd molar and from left upper 1st premolar to 2nd molar. In chest PA view, he had a forked rib in the left 4th rib and in skull PA view the calcification of falx cerebri was observed. There was not any skin lesion. After the preliminary evaluation, the patient was diagnosed with basal cell nevus syndrome and he underwent marsupialization for decreasing the size of cystic lesion and came to hospital for dressing 3days a week. As time goes by, the size of lesion decreased. So, one and half year after marsupialization, he underwent cyst enucleation and iliac bone graft for the mandibular lesion and buccal fat pad grafts for the maxillary lesions. After the surgery, the patient experienced normal healing without any complications and he is on long-term follow-up.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.5
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• pp.1-11
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• 2001

In the past, abundant and clean water was available for paper mills'use. However, the growth of population and industry made water less available nowadays. Also, environmental regulation limits wastewater discharge, which affects mill operation cost. Therefore, paper mills are under pressure to use more recycled water and mill system closure. As a result, chemical and physical parameters of water are changing and new environment if being created for microorganisms in paper mill system as well. The more soluble or suspended organic materials are increased as more water is recycled and less or scarce dissolved oxygen is available, depending on the degree of recycled water usage. Microorganism flora ill paper mill system will be a1so shifted according to the environmental change of mill system. Anaerobic bacteria, including sulfate reducing bacteria (SRB), will be dominant in the system as very low or almost no oxygen available in the system. Nevertheless, it is common in domestic paper mills that employ the same and old biocides as a means of microbial control, and microbiological control is often less recognized or even neglected. The right biocide selection for increased reductive environment of mills is critical for operation and estimated loss from paper quality defects such as sheet break, holes due to microbiological cause is tremendous compared to the microbiological control cost. It is imperative to investigate and diagnosis the environmental change of mills for right control of cumbersome microorganisms. Several useful diagnosis tools, including new technology employing OFM(Optical Fouling Monitor) in situ, are illustrated.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.4
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• pp.235-246
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• 2021

This study investigated the impact of baseflow on fish community in the Ungcheon stream (16.5 km long) located downstream of the Boryeong Dam, Korea. Based on field monitoring, there were five dominant fish species in the Ungcheon Stream accounting for 75% of the total fish community: Zacco platypus, Zacco koreanus, Tridentiger brevispinis, Rhinogobius brunneus, and Pungtungia herzi. These five fish species were selected as target species. HydroGeoSphere (HGS) and River2D models were used for hydrologic and hydraulic simulations, respectively. A habitat suitability index model was used to simulate fish habitat. To assess the impact of baseflow, each representative discharge was examined with or without baseflow. The HGS model was used to calculate baseflow within the study reach. This baseflow was observed to increase gradually with longitudinal distance. Validation of the hydraulic model dem onstrated that computed water surface elevated when baseflow was included, which was in good agreement with measured data, as opposed to the result when baseflow was excluded. Composite suitability index distributions and weighted usable area in the study reach were presented for target species. Simulations indicated that the baseflow significantly increased habitat suitability for the entire fish community. These results demonstrate that there should be a substantial focus on the baseflow for physical habitat simulation.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.106-109
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• 2022

The green-emitting Zn₂SiO₄:Mn²⁺ phosphor film was evaluated in a xenon excimer lamp. The phosphor film with 2 ㎛ thick was formed of monolithic structure on the inner side of quartz through a long-time annealing process of coated ZnO solution doped with Mn²⁺ ion and SiO₂ of quartz tube. The coated quartz was filled with 100 torr of xenon gas, and simultaneously both sides was melt and sealed. The xenon-field quartz tube was discharge by applying the voltage of 15 kV with a frequency of 26 kHz, and emitted the glow with dominant peak at 172 nm. The vacuum ultraviolet excited the inner-side coated Zn₂SiO₄:Mn²⁺ phosphor film, which emitted the pure and strong green light.

• Ocean and Polar Research
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• v.44 no.3
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• pp.249-260
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• 2022

This mini review examines the habitat connectivity and effectiveness of Korean Marine Protected Areas (MPAs) in the Yellow Sea Large Marine Ecosystem (YSLME) region. We first reemphasize that the Korean region of the YSLME is a single ecosystem (ecoregion) given the biophysical distribution patterns. The MPAs within the YSLME contribute about 50% to the total MPAs in Korea, accounting for about 10% of the territorial sea waters of Korea and 20% of the waters of YSLME on the Korean side. By area, national parks account for nearly 45% of the MPAs, followed by the wetland protected areas at 25%, with other types of MPA comprising the remaining 30%. Large MPA (> 100 km²) is the dominant type of MPA, accounting for 90% of the total area. We find that MPAs in the region are connected physically and perhaps also genetically. However, the level of protection was found to be low, and a no-take zone is rarely implemented. In addition, interrupted freshwater discharge caused by river-mouth dams poses a major hindrance to the physical connectivity of the MPAs. Restoration of the river-mouth dams and strengthened regulation on MPAs, with further expansion of MPAs in line with the current development of post-2020 global biodiversity frameworks, should be priorities for better management of marine resources. The newly revised law incorporating the concept of "Marine Ecosystem Axis Management" would reinforce the processes, and their effectiveness together with overall management of MPAs in Korea should be evaluated by designing appropriate measurement tools.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.7
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• pp.924-942
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• 2021

The expansion of the Changjiang Diluted Water (CDW) plume during summer is known to be a major factor influencing phytoplankton diversity, community structure, and the regional marine environment of the northern East China Sea (ECS). The discharge of the CDW plume was very high in the summer of 2020, and cruise surveys and stationary monitoring were conducted to understand the dynamics of changes in environmental characteristics and the impact on phytoplankton diversity and community structure. A cruise survey was conducted from August 16 to 17, 2020, using R/V Eardo, and a stay survey at the Ieodo Ocean Research Station (IORS) from August 15 to 21, 2020, to analyze phytoplankton diversity and community structure. The southwestern part of the survey area exhibited low salinity and high chlorophyll a fluorescence under the influence of the CDW plume, whereas the southeastern part of the survey area presented high salinity and low chlorophyll a fluorescence under the influence of the Tsushima Warm Current (TWC). The total chlorophyll a concentrations of surface water samples from 12 sampling stations indicated that nano-phytoplankton (20-3 ㎛) and micro-phytoplankton (> 20 ㎛) were the dominant groups during the survey period. Only stations strongly influenced by the TWC presented approximately 50% of the biomass contributed by pico-phytoplankton (< 3 ㎛). The size distribution of phytoplankton in the surface water samples is related to nutrient supplies, and areas where high nutrient (nitrate) supplies were provided by the CDW plume displayed higher biomass contribution by micro-phytoplankton groups. A total of 45 genera of nano- and micro-phytoplankton groups were classified using morphological analysis. Among them, the dominant taxa were the diatoms Guinardia flaccida and Nitzschia spp. and the dinoflagellates Gonyaulax monacantha, Noctiluca scintillans, Gymnodinium spirale, Heterocapsa spp., Prorocentrum micans, and Tripos furca. The sampling stations affected by the TWC and low in nitrate concentrations presented high concentrations of photosynthetic pico-eukaryotes (PPE) and photosynthetic pico-prokaryotes (PPP). Most sampling stations had phosphate-limited conditions. Higher Synechococcus concentrations were enumerated for the sampling stations influenced by low-nutrient water of the TWC using flow cytometry. The NGS analysis revealed 29 clades of Synechococcus among PPP, and 11 clades displayed a dominance rate of 1% or more at least once in one sample. Clade II was the dominant group in the surface water, whereas various clades (Clades I, IV, etc.) were found to be the next dominant groups in the SCM layers. The Prochlorococcus group, belonging to the PPP, observed in the warm water region, presented a high-light-adapted ecotype and did not appear in the northern part of the survey region. PPE analysis resulted in 163 operational taxonomic units (OTUs), indicating very high diversity. Among them, 11 major taxa showed dominant OTUs with more than 5% in at least one sample, while Amphidinium testudo was the dominant taxon in the surface water in the low-salinity region affected by the CDW plume, and the chlorophyta was dominant in the SCM layer. In the warm water region affected by the TWC, various groups of haptophytes were dominant. Observations from the IORS also presented similar results to the cruise survey results for biomass, size distribution, and diversity of phytoplankton. The results revealed the various dynamic responses of phytoplankton influenced by the CDW plume. By comparing the results from the IORS and research cruise studies, the study confirmed that the IORS is an important observational station to monitor the dynamic impact of the CDW plume. In future research, it is necessary to establish an effective use of IORS in preparation for changes in the ECS summer environment and ecosystem due to climate change.