• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.17-28
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• 2018

In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon material. Comparison study was also conducted by production of activated carbon from coconut shell (CCNS), Pinus, and Avicel, and each activated carbon was characterized by chemical composition, Raman spectroscopy, SEM analysis, and BET analysis. The amount of solid residue after thermogravimetric analysis of biomass samples at the final temperature of $750^{\circ}C$ was SAL > CCNS > Pinus > Avicel, which was the same as the order of activated carbon yields after catalytic activation. Specifically, SAL-derived activated carbon showed the highest value of carbon content (91.0%) and $I_d/I_g$ peak ratio (4.2), indicating that amorphous large aromatic structure layer was formed with high carbon fixation. In addition, the largest changes was observed in SAL with the maximum BET specific surface area and pore volume of $2341m^2/g$ and $1.270cm^3/g$, respectively. Furthermore, the adsorption test for three kinds of organic pollutants (phenol, 2,4-Dichlorophenoxyacetic acid, and carbofuran) were conducted, and an excellent adsorption capacity more than 90 mg/g for all activated carbon was determined using 100 ppm of the standard solution. Therefore, SAL, a condensed structure, can be used not only as a nanoporous carbon material with high specific surface area but also as a biosorbent applied to a carbon filter for remediation of organic pollutants in future.

• Journal of the Mineralogical Society of Korea
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• v.27 no.4
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• pp.301-310
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• 2014

To investigate the role of fault gauge in the behavior of heavy metals caused by the acid rock drainage in the area of pyrite-rich andesite, XRD, pH measurement, XRF, SEM-EDS, ICP, and sequential extraction method were used. Bed rock consists of quartz, pyrophyllite, pyrite, illite, and topaz, but the brown-colored fault gouge is composed of quartz, illite, chlorite, smectite, goethite, and cacoxenite. The mineral composition of bed rock suggests that it is heavily altered by hydrothermal activity. The concentrations of heavy metals in the bed rock are as follows, Zn > As > Cu > Pb > Cr > Ni > Cd, and those in fault gouge are As > Zn > Pb > Cr > Cu > Ni > Cd. The concentrations of the heavy metals in the fault gouge are generally higher than those in the bed rock, especially for Pb, As, and Cr, which were more than twice as those in the bed rock. It is believed that the difference in the amount of heavy metals between the bed rock and the fault gouge is mainly due to the existence of goethite which is the main mineral composition in the fault gouge and can play important role in sequestering these metals by coprecipitation and adsorption. The low pH, caused by oxidation of pyrite, also plays significant role in fixation of those metals. It is confirmed that the fractions of labile (step 1) and acid-soluble (step 2), which can be easily released into the environment, were higher in the bed rock. Those fractions were relatively low in fault gauge, suggesting that fault gauge can play important role as a sink of heavy metals to prevent those ones from being released in the area where the acid rock drainage can have an influence.

• Clinical and Experimental Pediatrics
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• v.45 no.8
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• pp.1000-1006
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• 2002

Purpose : In the course of treatment, patients with hematological or oncological disorders often develop pulmonary complication. The patients who develop a severe pulmonary complication have a poor outlook. The causes of pulmonary complication are either infectious or non-infectious in origin. We have analyzed the etiology and outcome of these patients admitted to the pediatric intensive care unit of Asan Medical Center. Methods : Medical records of 95 patients on Pediatric oncology service who were admitted to pediatric intensive care unit(PICU) of Asan Medical Center from Jan 1997 to May 2000 were retrospectively reviewed. Results : The mean age of the patients was 8.5 years(2 months-18 years). The underlying malignancies of these 95 patients were as following; acute lymphoblastic leukemia(31 cases), lymphoma (11 cases), acute myeloid leukemia(nine cases), brain tumor(eight cases) and other solid tumors(25 cases). Pulmonary complications included pneumonia, acute respiratory failure, pneumothorax and pleural effusion. The most common cause of pulmonary complication was infection(88%) in etiology. The overall mortality rate was 56.8%. Pulmonary complications in these patients carried high rates of mortality regardless of whether they were immune compromised(76%) or not(69%). Even without pulmonary complications, the hematological or oncological patients admitted to PICU had high mortality rates of 43%. Conclusion : Pulmonary complications are frequent finding in the hematological or oncological patients admitted to Intensive Care Unit. The main etiology of these pulmonary complications was infection, which carried a high mortality rate regardless of their immune status at the time when they were admitted to PICU.

• Clinical and Experimental Pediatrics
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• v.45 no.8
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• pp.1007-1015
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• 2002

Purpose : The aim of this study is to find a method to diagnose and treat children who showed benign hemophagocytic histiocytes in bone marrow examination. Methods : We analyzed the clinical data of thirty patients retrospectively who showed benign hemophagocytic histiocytes in bone marrow examination from January 1995 to November 2001 at Keimyung University Dong-san Hospital. Bone marrow histiocytes were classified into a few, some, and many according to the number of histiocytes comparing with the white cells. Results : The age of thirty patients ranged from two months to 15 years. The median age was 5.6 years with male predominance(2.3 : 1). The most frequent clinical manifestation was fever; others were respiratory symptom, hepatosplenomegaly, lymphadenopathy and skin rash(in order of frequency). Common laboratory findings were leukopenia, thrombocytopenia, anemia and abnormal liver function test. Infection was present in 30 patients; causative organisms were documented in 15 patients, and bacterial infection was more common. Epstein Barr virus was the cause of infection in four patients. Bone marrow examination showed a few(20.0%), some(75.0%) and many(30.0%) hemophagocytic histiocytes. Combination immunochemotherapy including immunoglobulin, steroids and cyclosporine were helpful in 22 out of 30 patients. The mortality rate was high in young patients who showed some to many hemophagocytic histiocytes. Conclusion : Bone marrow examinations and early detection of histiocytes will be helpful in children who have fever, hepatosplenomegaly and abnormal liver function test. Immunochemotherapy were helpful and further investigation will be needed for the detection of the relationship between the bone marrow findings and prognosis.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.186-192
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• 2002

Purpose : Measurement of transmission dose is useful for in vivo dosimetry. In this study, previous algorithm for estimation of transmission dose was modified for use in cases with tissue deficit. Materials and Methods : The beam data was measured with flat solid phantom in various conditions of tissue deficit. New algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. The algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients using multiple sheets of solid phantoms. Results : The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within ${\pm}1.0\%$ in most situations and within ${\pm}3.0\%$ in experimental settings with irregular contours mimicking breast cancer treatment set-up. Conclusion : Developed algorithm could accurately reflect the effect of tissue deficit and irregularly shaped body contour on transmission dosimetry.

• Applied Microscopy
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• v.35 no.3
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• pp.165-176
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• 2005

Studies on molecular plasticity of Bermann glia (BG) after harmaline-induced Purkinje cell (PC) degeneration in the rat cerebellum. The intimate structural relationship between BG and PC, evidenced by the sheathing of the PC dendrites by veil-like process from the BG has been suggestive of the close functional relationship between these two cell types. However, little is known about metabolic couplings between these cells. This study designed to investigate molecular plasticity of BG in the rat cerebellum in which PCs were chemically ablated by harmaline treatment. Immunohistochemical examination reveals that harmaline induced PC degeneration causes a marked glial reaction in the cerebellum with activated BG and microglia aligned in parasagittal stripes within the vermis. In these strips, activated BG were associated with upregulaion of metallotheionein, while GLAST and was down regulated, as compared with nearby intact area where both BG are in contact with PCs. The data from this study demonstrate that BG can change their phenotypic expression when BG loose their contact with PCs. It is conceivable that activated BG may upregulate structural proteins, metallothionein expression to use for their proliferation and hypertrophy; metallothionein expression to cope with oxidative stress induced by PC degeneration and microglial activation. On the contrary, BG may down regulated expression of GLAST because sustained loss of contact with PCs would eliminate the necessity for the cellular machinery involved glutamate metabolism. In conclusion, BG might respond man to death of PCs by undergoing a change in metabolic state. It seems possible that signaling molecules released from PCs regulates the phenotype expression of BG. Also ultrastructures in the organelles of normal PC and BG are distinguished by mitochondrial appearance, and distributed vesicles at the synaptic area in the cytoplasm.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.9-20
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• 2007

PAHs(Polycyclic Aromatic Hydrocarbons) are widespread contaminants in the marine environment. They are of mainly anthropogenic origin from urban runoff, oil spill and combustion of fossil fuels. Some PAHs are potentially carcinogenic and mutagenic to aquatic organism The contamination of PAHs in the coastal environments has not been well known yet in Korea. This study was carried out to survey the contamination of PAHs in sediments around Gwangyang bay. The Yeosu petrochemical industrial complex, POSCO(Pohang steel company) and Gwangyang container harbor are located around the bay. PAHs in sediment samples were extracted in soxhlet extractor and were identified and quantified by GC-MS(Gas Chromatography-Mass Spectrometry) TOC(Total Organic carbon) and textural parameters in sediment samples were also analyzed 13 species of PAHs were detected at all of the surface sediments. Total PAHs concentrations in the surface sediments ranged from 171.40 to $1013.54{\mu}g/kg$ dry wt.. In most of the surface sediments, Naphthalene was the highest in the range of 14.08 to $691.39{\mu}g/kg$ dry wt. and Anthracene was the lowest in the range of 0.49 to $22.66{\mu}g/kg$ dry wt.. The correlation coefficients between individual PAHs and Total PAHs in the surface sediments were relatively higher in the low molecular compounds such as Naphthalene and Phenanthrene. In the relationship of the P/A(Phenanthrene/Anthracene) ratio and F/P(Fluoranthene/Pyrene) ratio, P/A ratio was generally above 10 and F/P ratio was shown to be above 1 in all sediment samples. These data indicate that PAHs in sediments around Gwangyang bay seem to be of both pyrolytic and petrogenic origin. Total PAHs in the surface sediments were correlated with TOC and textural parameters. The values of PAHs in the surface and core sediments were lower than the biological effect guidelines.

• The Korean Journal of Malacology
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• v.29 no.1
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• pp.51-63
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• 2013

To assess the effect of environmental factors on the sustainability of cultured production shellfish, we investigated the habitat characteristics of tidal flat (Namhae-po in Taean). We measured the physiochemical parameters (temperature, salanity, pH, dissolved oxygen and nutrients) and the geochemical characteristics (chemical oxygen demand, ignition loss, C/N ratio and C/S ratio). Surface sediments were collected from several site of tidal flat to examine the geochemical characteristics of both the benthic environment and heavy metal pollution. The grain size for research area of tidal flat were similar at the ratio of silt and clay in comparison with the other site of it. The C/N ratio was more than 5.0, reflecting the range arising from the mix of marine organism and organic matter. The C/S ratio (about 2.8) showed that survey area had anoxic or sub-anoxic bottom conditions. The enrichment factor (Ef) and index of accumulation rate (Igeo) of the metals showed that those research areas can be classified as heavily polluted, heavily to moderately polluted, or more or less unpolluted, respectively. Adult surf clam (Mactra veneriformis) density was highest at St. 2 (middle part of the Namhae-po), on the other hand, surf clam spat density was highest at St. 3 (lower part of the Namhae-po). Heavy rain, terrigenous suspended clay with fresh water from neighboring agricultural land, and severe high air temperature during summer could be thought as detrimental causes of spat and adult mortality in Namhae-po tidal flat. We suggested that the growth of shellfish in the tidal flat was effected by the various environmental conditions, so an improvement in the cultured method was needed.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.3
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• pp.165-170
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• 2013

In this study, physico-chemical properties and environmental fate were investigated and ecotoxicity tests using fish, daphnia and algae were conducted for an initial ecological risk assessment of 1,2-Benzisothiazol-3-one. Due to low volatility of the test substance under environmental conditions, it is likely to distributed in soil and water environment. The compound has low adsorption in the soil, with low bioconcentration potential. Acute toxicity results showed that 96 h-$LC_{50}$ for Oryzias laties was 4.7 mg/L (measured) and 48h-$EC_{50}$ for Daphnia magna was 3.3 mg/L (measured). In a growth inhibition test with Pseudokirchneriella subcapitata, 72 h-$EC_{50}$ was 0.456 mg/L (growth rate, nominal) and 0.262 mg/L (yield, nominal). Using the acute toxicity value of algae, predicted no-effect concentration (PNEC) in the aquatic environment was determined to be 2.62 ${\mu}g/L$ using an factor of 100. According to globally harmonized system (GHS), the compound was categorized as aquatic acute 1 for algae, while it was categorized as aquatic acute 2 for fish and daphnia. This screening assessment suggests that the test substance may pose ecological risks in the aquatic environment.

• Journal of Soil and Groundwater Environment
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• v.11 no.3
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• pp.31-42
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• 2006

Drought indices, such as PDSI (palmer Drought Severity Index), SWSI (Surface Water Supply Index) and SPI (Standardized Precipitation Index), have been developed to assess and forecast an intensity of drought. To find the applicability of groundwater level data to a drought assessment, a correlation analysis between SPI and groundwater levels was conducted for each time series at a drought season in 2001. The comparative results between SPI and groundwater levels of shallow wells of three national groundwater monitoring stations, Chungju Gageum, Yangpyung Gaegun, and Yeongju Munjeong, show that these two factors are highly correlated. In case of SPI with a duration of 1 month, cross-correlation coefficients between two factors are 0.843 at Chungju Gageum, 0.825 at Yangpyung Gaegun, and 0.737 at Yeongju Munjeong. The time lag between peak values of two factors is nearly zero in case of SPI with a duration of 1 month, which means that groundwater level fluctuation is similar to SPI values. Moreover, in case of SPI with a duration of 3 month, it is found that groundwater level can be a leading indicator to predict the SPI values I week later. Some of the national groundwater monitoring stations can be designated as DIW (Drought Index Well) based on the detailed survey of site characteristics and also new DIWs need to be drilled to assess and forecast the drought in this country.