• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.371-386
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• 1994

Ecological examinations of the radial growth Patterns of pine trees(Pinus densiflora Sieb. et Zucc) growing on Mt. Namsan in central Seoul were made to test a Proposition that the pine trees decline due to the influence of air pollution and acid rain, which was proposed by some researchers in Korea, and the potential effects of current level of air pollutants to the growth of the Pine trees in central Seoul have been speculated. Tree-rings of 40 trees sampled at 3 sites of Mt. Namsan were prepared and examined using a Computer-aided Tree-Ring Measuring System at Kookmin University, Korea. Air Pollutant data collected by the Ministry of Environment( MOE ) and the Forestry Research Institute(FRI) were used to infer the general conditions of the environment. Correlation analysis was applied to the data set of tree growth and the other environmental factors. General information derived from the close examination of the tree-rings and the data on air pollution, drought and the other biological conditions suggested that the growth of the pine trees was severely affected by the occurrence of drought(climatic variation), the prevalence of the pine leaf gall midges(insects), and the suppression by the black locust trees(Robinia pseudo-acacia L.) (competition among trees). While the current condition of air pollution in Seoul cannot be categorized as good, the concentrations of air pollutants are not so high as to cause acute damages to the trees. In addition, while the data of rain acidity showed episodic low PHs of under 4.0, the average of them is far less acidic than those which were observed in either northeastern United States or central Europe, where the decline of trees were not solely attributed to any of the air pollutants. Considering the sequential facts that one of the most important environmental factors that affect the growth of trees is weather condition of the forest that the proposition of the decline of the pine trees was made without careful examination of the growth patterns and past growth history of them as well as the complex influences of many other factors including the weather conditions to the growth of trees, and that no objective explanation has been made on the causal relationships between the current condition of air pollution and the growth of the trees, such a proposition should be evaluated as invalid for the explanation of tree growth on Mt. Namsan in central Seoul, Korea. The author evaluates the factors of air pollution (including acid rain) as the predisposing factors, which may have the Potentials to chronically affect the tree growth at the forest ecosystem on Mt. Namsan for a long period of time. Ecosystem ecological studies should be further carried out to carefully explain both the functional and the structural aspects of the ecosystem processes, which include the biogeochemistry and the long-term changes of soil conditions as well as the growth of the other tree species on the mountain.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.399-404
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• 1997

This paper is presenting a practical result of environmental manipulation effect on pine mushroom Tricholoma matsutake yield and a discussion of key factor seeking for improving pine mushroom production by analyzing the effects on mushroom yield for 10 years with applying five kinds of environmental control at the pine stands located in Namwon, Chollabuk-do, Korea. The environmental controls included density control and forest floor manipulations, and the treatments were applied during early summer of 1983. The mushroom yield itself did not show statistically significant differences among the treatments. But, we could manifest the treatment effects by calculating the relative yield in percent on the basis of pretreatment yield collected in 1982. The forest floor manipulation with density control may affect pine mushroom yield in short term, and continuous management should be applied to keep and improve the mushroom production. The fine root activity was the most important factor of pine mushroom production at the Namwon research site since the floor raking resulted in the largest effect on the mushroom yield although the environmental condition for the growth of fungi is important for pine mushroom production. In addition, the pine mushroom forest with sandy soils demands adequate litter layer since the litter removal showed relatively detrimental effects on pine mushroom yield compared to that in litter covered plot at the research site. That is, soil texture should be considered for forest floor manipulation, and it is reconfirmed that the environmental control to improve pine mushroom production should be applied differently by each region.

• Journal of Nutrition and Health
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• v.47 no.1
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• pp.1-11
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• 2014

Purpose: Several studies have proven that EGCG, the primary green tea catechin, and glucosamine-6-phosphate (PGlc) reduce triglyceride contents in 3T3-L1 adipocytes. The objective of this study is to evaluate the combination effect of EGCG and PGlc on decline of accumulated fat in differentiated 3T3-L1 adipocytes. Methods: EGCG and PGlc were administered for 6 day for differentiation of 3T3-L1 adipocytes. Cell viability was measured using the CCK assay kit. In addition, TG accumulation in culture 3T3-L1 adipocytes was investigated by Oil Red O staining. We examined the expres-sion level of several genes and proteins associated with adipogenesis and lipolysis using real-time RT-PCR and Western blot analysis. A flow cytometer Calibar was used to assess the effect of EGCG and PGluco on cell-cycle progression of differentiating 3T3-L1 cells. Results: Intracelluar lipid accumulation was significantly decreased by combination treatment with EGCG $60{\mu}M$ and PGlc $200{\mu}g/m$ compared with control and EGCG treatment alone. In addition, use of combination treatment resulted in directly decreased expression of $PPAR{\gamma}$, $C/EBP{\alpha}$, and SREBP1. In addition, it inhibited adipocyte differentiation and adipogenesis through downstream regulation of adipogenic target genes such as FAS, ACSL1, and LPL, and the inhibitory action of EGCG and PGlc was found to inhibit the mitotic clonal expansion (MCE) process as evidenced by impaired cell cycle entry into S phase and the S to G2/M phase transition of confluent cells and levels of cell cycle regulating proteins such as cyclin A and CDK2. Conclusion: Combination treatment of EGCG and PGlc inhibited adipocyte differentiation through decreased expression of genes related to adipogenesis and adipogenic and cell cycle arrest in early stage of adipocyte differentiation.

• Journal of the Mineralogical Society of Korea
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• v.15 no.2
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• pp.104-113
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• 2002

The sorption of Cd$^{2+}$ on calcite was studied in aqueous solutions of several electrolytes. The Cd$^{2+}$ concentration, 10$^{-8}$ M, was kept well below saturation with respect to CdCO$_3$(s). Sorption behavior of Cd$^{2+}$ in different ionic strengths of NaClO$_4$solutions shows that sorption is independent of ionic strength. This result suggests that Cd$^{2+}$ sorption on calcite surface is of a specific nature, and adsorption is controlled by an inner-sphere type of surface complex. Two stages in the sorption behavior could be identified: an initial rapid uptake, followed by slower uptake reaching a maximum steady state by 145 hrs. No evidence was observed for surface precipitation, although it can not be entirely ruled out. Desorption of Cd$^{2+}$ from the calcite surface after resuspension into Cd-free solution is initially very rapid, but depends partly on the previous sorption history. Desorption behavior of Cd$^{2+}$ show that an initial rapid desorption followed either by slow uptake reaching a maximum, as in the adsorption experiments, or slowing desorption to reach a steady state minimum. This irreversible behavior of Cd$^{2+}$ sorption and desorption may act as one of the controls for regulating the mobility of dissolved Cd$^{2+}$ natural aqueous systems. Calculated adsorption partition coefficients suggest that overall sorption and desorption process in the concentration range are controlled by d single mechanism.ingle mechanism.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.3
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• pp.315-320
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• 2006

For the purpose of developing natural antioxidant, the antioxidative and antimicrobial activities of phenolics isolated from spices were determined. The total phenolics contents of spices were more than 20 mg/g in water and 60% ethanol extracts of all spice, oregano and sage. Electron donating ability assay showed high inhibition rate in water extracts of all spice, nutmeg, white pepper, oregano and sage and 60% ethanol extracts of oregano and nutmeg. Antioxidant protection factor (PF) was higher than 1.2 in 60% ethanol extracts of sage, all spice and oregano and water extracts of sage. The 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical decolorization (ABTS) was inhibited by more than 90% by water and 60% ethanol extracts of all spice and oregano. TBARS (thiobarbituric acid reactive substances) were $0.7{\mu}M$ in the control and $0.2{\mu}M$ in water and 60% ethanol extracts the each spices. The water extracts of each spices did not have antimicrobial activity against H. pylori; however, the 60% ethanol extracts from oregano revealed the high antimicrobial activity as clear zone of 10 mm and inhibition rate of 77.2% with $200{\mu}g/mL$ of phenolics content. The result suggests that spices extract may be useful as potential sources of anti-Helicobacter pylori, antioxidant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.706-712
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• 1999

PSD (particle size distribution) for 2,000 mg/$\ell$ natural loess in seawater showed normal distribution cure at 0 minute settling time, accompanying with very large particle distribution range with its mean particle diameter of 31.6 $\mu$m and coencient of variance of $72.6\%$, With elapsed time it showed that the PSD was rapidly changed from normal distribution cure to abnormal distribution curve, steepened the right-hand side of it and its coefficient of variance was getting increased because of rapid settling of large size particles, Cumulative weight distribution showed that 2,000 mg/$\ell$ natural loess in seawater was almost $100\%$ constituted of particles bigger than 20 $\mu$m in diameter. Ratio of $V_s/(D_{bm})^{1/2}$ for loess particles in seawater was increased with increase of particle size in geometrical progression. Almost all loess particles in seawater had Stokes settling velocity not less than 2,255 times of Brownian diffusion coefficient, There was almost to EDL (about 0.4 nm) around natural loess particles in seawater, Thus, there was always LVDW attractive force between loess particles approaching each other in seawater, and almost no EDL repulsive force. Loess particles were not always in the condition of easy floe formation. Concentration of natural loess in seawater increasing from 400 mg/$\ell$ to 10,000 mg/$\ell$, characteristics of the settling was changed from Type I settling (discrete settling) to Type II settling (flocculation settling). PVD (particle volume distribution) showed that natural loess particles in seawater were largely constituted of two types of particles, such as rapidly settling particles and suspended and dispersed particles for a long time. Amount of the latter was much less than that of the former.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.654-661
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• 2007

The goal of this research was to identify the impact of silicate polymerization on the formation of insoluble aluminiumsilicate salts which could be a cause of irreversible fouling in the membrane process by lab-scale test. For this, the amount and characteristics of precipitates that were formed in six samples with different Al and Si concentration were analyzed. And the particles was also observed by SEM-EDS(Scanning Electron Microscope - Electron Dispersion Spectrophotometer) to compare morphology and ratio of Al and Si in each precipitates. Finally the reactive and nonreactive silicate contents in the solution and precipitates were analyzed to calculate silicate form content in each fraction. The amount of precipitates was in proportion to the total concentration of both element in solution. And the amount of insoluble particle that was not dissolved in the acid solution was recorded the highest in the sample 2 of which Si concentration was lower than the saturation concentration, 50 mg/L. The content of reactive silicate in precipitates was also recorded the highest value in sample 2 of which almost silicate form was reactive. When the silicate concentration is same, that value was recorded the highest in the sample with highest Al concentration. The SEM morphology of the precipitates was similar to that of Aluminiumhydroxide and the insoluble precipitates was not dissolved in acidic solution with pH 2.7 was able to observed only in sample 2. The ratio of Al and Si in the precipitates was ranged $0.48\sim3.14$, thai of sample 2 was recorded the highest value, 3.14. It is concluded that the insoluble aluminiumsilicate could be easily formed in the solution of which silicate exist as a reactive form and coexisting Al is sufficient.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.3
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• pp.302-313
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• 2008

The purposes of this study are to investigate the concentration levels of fine particles, so called PM$_{2.5}$, to identify the affecting sources, and to estimate quantitatively the source contributions of PM$_{2.5}$. Ambient air sampling was seasonally carried out at two sites in Pohang(a residential and an industrial area) during the period of March to December 2003. PM$_{2.5}$ samples were collected by high volume air samplers with a PM$_{10}$ Inlet and an impactor for particle size segregation, and then determined by gravimetric method. The chemical species associated with PM$_{2.5}$ were analyzed by inductively coupled plasma spectrophotometery(ICP) and ion chromatography(IC). The results showed that the most significant season for PM$_{2.5}$ mass concentrations appeared to be spring, followed by winter, fall, and summer. The annual mean concentrations of PM$_{2.5}$ were 36.6 $\mu$g/m$^3$ in the industrial and 30.6 $\mu$g/m$^3$ in the residential area, respectively. The major components associated with PM$_{2.5}$ were the secondary aerosols such as nitrates and sulfates, which were respectively 4.2 and 8.6 $\mu$g/m$^3$ in the industrial area and 3.7 and 6.9 $\mu$g/m$^3$ in the residential area. The concentrations of chemical component in relation to natural emission sources such as Al, Ca, Mg, K were generally higher at both sampling sites than other sources. However, the concentrations of Fe, Mn, Cr in the industrial area were higher than those in the residential area. Based on the principal component analysis and stepwise multiple linear regression analysis for both areas, it was found that soil/road dust and secondary aerosols are the most significant factors affecting the variations of PM$_{2.5}$ in the ambient air of Pohang. The source apportionments of PM$_{2.5}$ were conducted by chemical mass balance(CMB) modeling. The contributions of PM$_{2.5}$ emission sources were estimated using the CMB8.0 receptor model, resulting that soil/road dust was the major contributor to PM$_{2.5}$, followed by secondary aerosols, vehicle emissions, marine aerosols, metallurgy industry. Finally, the application and its limitations of chemical mass balance modeling for PM$_{2.5}$ was discussed.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.6
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• pp.422-429
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• 2013

It is generally known that the increase of the Earth surface temperature due to the global warming together with the land desertification by rapid urban development has caused severe climate and weather change. In desert or desertification land, it is observed that there are always severe flooding phenomena, even if desert sand has the high porosity, which could be believed as the favorable condition of rain water infiltration into ground water. The high runoff feature causes possibly another heavy rain by quick evaporation with the depletion of underground water due to the lack of infiltration. The basic physics of desert flooding is reasonably assumed due to the thermal buoyancy of the higher temperature of the soil temperature than that of the rain drop. Considering the importance of this topic associated with water resource management and climate disaster prevention, no systematic investigation has, however, been reported in literature. In this study, therefore, a laboratory scale experiment together with the effort of numerical calculation have been performed to evaluate quantitatively the basic hypothesis of run-off mechanism caused by the increase of soil temperature. To this end, first, of all, a series of experiment has been made repeatedly with the change of soil temperature with well-sorted coarse sand having porosity of 35% and particle diameter, 2.0 mm. In specific, in case 1, the ground surface temperature was kept at $15^{\circ}C$, while in case 2 that was high enough at $70^{\circ}C$. The temperature of $70^{\circ}C$ was tested as this try since the informal measured surface temperature of black sand in California's Coachella Valley up to at 191 deg. $^{\circ}F$ ($88^{\circ}C$). Based on the experimental study, it is observed that the amount of runoff at $70^{\circ}C$ was higher more than 5% compared to that at $15^{\circ}C$. Further, the relative amount of infiltration by the decrease of the surface temperature from 70 to $15^{\circ}C$ is about more than 30%. The result of numerical calculation performed was well agreed with the experimental data, that is, the increase of runoff in calculation as 4.6%. Doing this successfully, a basic but important research could be made in the near future for the more complex and advanced topic for this topic.

• Clinical and Experimental Pediatrics
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• v.50 no.2
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• pp.178-181
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• 2007

Purpose : The renal manifestations of tuberous sclerosis complex (TSC) are remarkably diverse, including polycystic kidney disease, simple renal cysts, renal cell carcinomas, and angiomyolipomas. All of these occur in children as well as adults in TSC. Angiomyolipomas, which can cause spontaneous life-threatening hemorrhages, are by far the most prevalent and the greatest source of morbidity. Here, we will address our experience, adding to the literature on pediatric patients with TSC requiring evaluation and treatment for renal manifestations. Methods : A retrospective analysis was made on 19 patients in whom TSC was diagnosed between May 2001 and Oct. 2005 at Severance Hospital. All patients had clinical diagnoses of TSC as defined by the 1998 tuberous sclerosis complex consensus conference. Results : The patients consisted of 13 boys and 6 girls with a mean age of 7.3 years (range 1 to 22). The renal disease associated with TSC included angiomyolipoma in nine patients (47.4 percent), renal simple cyst in one (5.3 percent), hydronephrosis in one (5.3 percent) patient. Eight patients (42.1 percent) presented with normal kidney contours at abdominal ultrasonography. One patient underwent renal replacement therapy due to chronic renal insufficiency after nephrectomy. Hemorrhage from angiomyolipoma was not detected. Conclusion : In our review of 19 cases of TSC, renal manifestations are reported in 57.9 percent of patients. Asymptomatic angiomyolipoma associated with TSC grow gradually, although severe hemorrhages are rare. So patients with TSC should be followed up with serial computerized tomography or abdominal ultrasonography. And also, renal function should be monitored conservatively.