• Journal of Aquaculture
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• v.18 no.4
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• pp.260-266
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• 2005

In order to obtain the aquaculture fundamental data far resources enhancelnent of the Protothaca jedoensis, the egg development and larva growth were investigated at different conditions such as water temperature, phytoplankton and density. Water temperature, at which P. jedoensis egg successfully completed development, ranged from $15{\~}30^{\circ}C$. The required time from fertilization to D-shaped larva was 39.7 hours at $15^{\circ}C$, 31.2 hours at $20^{\circ}C$, 26.8 hours at $25^{\circ}C$ and 26.2 hours at $30^{\circ}C$ P. jedoensis. In regard to water temporature, growth and survival rates of larvae were high at $30^{\circ}C$. In growth and survival rates of larvae with various rearing densities, the highest aver-age growth and survival rates were 4${\~}$6 ind./ml When larvae were fed mixed phytoplankton, such as Isochrysis galbana, Pavlova lutheri and Chaetoceros calcitrans, their growth and survival rates were the high among the groups. In growth and survival rates of larvae with various rearing food concentrations, the highest average growth and survival rates were $218{\mu}m$, and $45\%$ at the food concentration of $1{\times}10^4$ cells/ml, respectively.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.324-332
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• 2001

Foods constitute a large portion of heavy metal exposure toward general population and attract a deep concern with respect to assuring human health. This study summarized published data in Korea on the content, and dietary intake of heavy metals and assessed their risk potential in comparison with foreign data. An analysis for the yearly fluctuation of metal contents including arsenic, cadmium, mercury and lead by flood group (marine fishes, coastal shellfishes, freshwater fishes, cereal grains) exhibited a decreasing trend from the 1970s to the 1990s. When compared with domestic standards of heavy metals, their mean contents were below the limit and their maximum values seldom exceeded the limit. The data on the dietary intake of heavy metals by Koreans showed a decreasing trend from the 1980s to the 1990s. The average intakes offs and Hg were 6∼8% and those of Cd and Pb were 50∼80% of PTWI(provisional tolerable weekly intake), all of which were below the tolerance. As the extreme intakes of these metals may exceed the PTWI, a careful assessment for them may be necessary. Dietary intakes of Cd, Hg and Pb by Koreans lie in the mid-level among countries cited in the GEMS/Food monitoring data. As fishery foods are suspecious of contamination with Hg, Cd and As, and floods in general are with Pb, it is necessary to establish legal limits for these metals and monitor any progress of their contamination. Furthermore, overall assessment of exposure to heavy metals from all sources including floods, air, drinking water and occupation should be made in order to confirm the dietary risk factors and to assure the safety of food resources.

• Journal of the Mineralogical Society of Korea
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• v.12 no.1
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• pp.43-53
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• 1999

The medical mineral menas a single mineral or a complex of minerals. It is natural material. using the medical action of he major or the minor elements, and traditional medicine stuff which has been used since long time ago. Jusa, cinnabar as the mineral name, is the product of the hydrothermal process. It is used to relax the body and cure high blood pressure, apoplexy and cardiopathy. Jusais the major component of "An shin hwan" and "Woo hwang chung shim hwan" nowadays because it has such an excellent calm effect. In addition, it is used to cure cancers such as esophageal cancer and gastric cancer. Jusa composed of mercuric sulfide causes mercury poisoning such as Minamata disease. It is dealt with mineralogical property and chemical composition medical stuff in Korea and China, as well asmercury poisoning and medical action of Jusa in this study. In order to predct accumulation of the interior of the body of the major and minor elements in Jusa, leaching experiment of Jusa by artificial gastric juice was done as well as thermodynamic reaction modelling to know concentration of each species of body fluid. The minor elements of 24 species such as As, Pb, Cd, a and Fe by leaching reaction of Jusa and artificial gastric juice were leached. We can know the fact that as is less than 1 ppm, Hg is less than 25 ppm and Cd and m are not detected. In addition, mercury exists as species of Hg2+, HgCl+, HgCl2, HgCl3-, HgCl42-, HgClOH, HgS(H2S)2, Hg(HS)3-, HgS22-, HgOH and Hg(OH)2 by reaction modelling between Jusa and artificial gastric juice. The concentration of sulfide complexes is 24.2 ppm and that of others is less than 10 ppm. According to increasing pH, the concentration of HgS(H2S)2, Hg(HS)3+, HgS22- and Hg(OH)2 increases, whereas the concentration of HgCl+, HgCl2, HgCl3- and HgCl42- decreases. Therefore, Jusa is very useful for the development of new medicine because it is possible to predict formation of the body species and species accumulation on mercury known as a toxic element and concentration changes of toxicity and efficiency.city and efficiency.

• Clean Technology
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• v.26 no.1
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• pp.39-54
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• 2020

This study analyzed the groundwater quality according to the depth and geological features in Gyeongsangnam-do area using groundwater quality monitoring network data to grasp the groundwater quality characteristics and to provide basic data for policy making on efficient groundwater management. Five hundred and three data sets were acquired from background water quality exclusive monitoring network in soil groundwater information system for five years (2013 ~ 2017). Except for the total coliforms and tracer items such as mercury, phenol, and others, the parameters of water quality were significant or very significant, depending on depth and geological features. As the depth got deeper, the average value of pH and electrical conductivity increased; water temperature, dissolved oxygen, oxide reduction potential, arsenic, total coliforms, and turbidity decreased; and total unfit rate for drinking water standards was lower. It was found that the sum of the positive and negative ions was the highest in the clastic sedimentary rock and the lowest in metamorphic rock. The total unfit rate for drinking water standards was the highest for metamorphic rocks, followed by clastic sedimentary rock and unconsolidated sediments and, finally, intrusive igneous rock with the lowest penetration. The Na-Cl water type, which indicated the possibility of contamination by external pollutants, appeared only at some points in shallow depths and in clastic sedimentary rocks.

• Journal of Environmental Health Sciences
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• v.40 no.4
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• pp.279-293
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• 2014

Objectives: Children are more susceptible to heavy metal toxicity than adults. The purpose of this study was to evaluate heavy metal concentrations in the blood of Korean preschoolers and investigate the association between metals in blood and related factors. Methods: A total of 512 subjects from 36 to 83 months of age were sampled. A questionnaire survey was performed and the levels of lead, mercury and cadmium were measured in the blood samples of all subjects. Their parents were interviewed in order to obtain information on basic characteristics, dietary patterns, socio-economic factors, and indoor/outdoor environment of the preschoolers. Multiple linear regression was used to analyze the association between the above factors and lead, mercury or cadmium concentrations. Results: The geometric mean concentrations of lead, mercury and cadmium in the blood were $1.45{\pm}1.58{\mu}g/dL$, $2.14{\pm}1.74{\mu}g/dL$ and $0.23{\pm}1.91{\mu}g/dL$, respectively. Results from multiple linear regression analysis showed that blood lead levels were associated with birth weight and paternal smoking status. Daily mercury intake from food and maternal education were also shown to influence mercury concentrations in blood. Also, blood cadmium concentrations were associated with maternal age and having a bus garage near the place of residence. Conclusion: This study suggests that smoking status, dietary patterns and the environmental status near the residence should be considered as important factors for preventable sources of heavy metal exposure in preschoolers.

• Journal of Life Science
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• v.20 no.2
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• pp.202-207
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• 2010

Ras genes are responsible for up to 30% of human tumor mutations and are composed of three isoforms: H-Ras, K-Ras and N-Ras. The post-translational modification of the CAAX motif of the Ras protein is essential in Ras actions. In the present study, we studied the effects of novel farnesyl transferase inhibitors (FTIs), YH3938 and YH3945, on the actions of oncogenic mutants of H-Ras, K-Ras and N-Ras. YH3938 and YH3945 completely reverted the proliferation and morphology of oncogenic H-Ras-transformed Rat2 cells, but not of oncogenic K-Ras-transformed Rat2 cells. Oncogenic N-Ras-transformed Rat2 cells were slightly affected. Activation of SRE promoters by oncogenic H-Ras and N-Ras, but not by K-Ras, were inhibited by treatment with YH3938 and YH3945. Using bandshift analysis, YH3938 suppressed the processing of oncogenic H-Ras and N-Ras, but not that of oncogenic K-Ras protein. YH3945 only inhibited the processing of H-Ras. From these results, we conclude that YH3938 and YH3945 specifically inhibit actions of oncogenic H-Ras through inhibition of its farnesylation, that YH3938 also inhibits N-Ras activity in a dose-dependent manner, and that these drugs have no effect on oncogenic K-Ras activity.

• Korean Journal of Ecology and Environment
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• v.33 no.1 s.89
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• pp.31-37
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• 2000

For the purpose of surveying the physicochemical composition of sediment collected from Kwangyang Bay, the percentage of water loss, COD, $H_2S$, grain size and 10 heavy metals were studied at 17 sites. During the surveying period, the changes of the percentage of water loss were appeared $35.5\;{\sim}\;53.8%$. COD and $H_2S$ were showed $3.8\l{\sim}\;12.9\;mg/g$, and $0.1\;{\sim}11.4\;{\mu}g/g$, respectively, In composition of grain size on the sediment, percentages of grain sizes under $74\;{\mu}m$ were varied from 40.5% to 86.7% and above $74\;{\mu}m$ were varied from 11.5% to 43.0%. From the spatial distribution of heavy metal using contour map, we can suppose some heavy metal discharges which affect sediment of Kwangyang Bay, It was estimated that Shinpung creek, Ssang-bong creek, and draining area of sewange treatment plant were the main discharge among the heavy metal output sources. By comparison between present study and heavy metal guideline of nonpolluted sea sediment that is provided by EPA, US, it was showed that the contents of Pb and Hg were acceptable but contents of Mn, Zn, Cu, Fe, As, and Cr were higher than those of EPA guideline.

• Korean Journal of Environmental Biology
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• v.20 no.4
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• pp.360-365
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• 2002

The variety and density of entomopathogenic nematodes from the polluted soils of heavy metals were examined. In order to investigate the pollution of heavy metals in soil, 300 sites in kyungsangbuk-do were collected from March to October in 2001. We measured the contents of seven heavy metal elements (Cd, Cu, As, Hg, Pb, Cr^{6+}$, CN) and than cheesed soil of 25 sites with high concentration of heavy metals. The seven strains of nematodes were isolated from seven samples by silkworm host (Bombyx mori mori) and white trap. Isolated nematodes are composed of two families, one order. The members of Rhabditida were isolated in the soil with mean Cd content of 0.870 ppm. And they were isolated in the soil samples with As content less than 0.745 ppm. However they were isolated regardless of concentration of Cu and Pb. The members of Cylindrocorpidae were isolated in the soil samples with Cr^{6+}$ content less than 0.05 ppm. Any entomopathogenic nematode was not detected in the CN polluted soil. Isolated nematodes successfully cultured on the silkworm host and were confirmed the pathogenicity, multiplicity, and tolerance against various condition of preservation. Which proved its potential usefulness as biological agent.

• Journal of Life Science
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• v.21 no.4
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• pp.584-588
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• 2011

This study was conducted to investigate the effects of organic materials, chitosan, wood vinegar, and EM active solution, on soil microbial and growth in Chinese cabbage. The organic materials were treated with chitosan, wood vinegar, and EM (effective microoganism) active solution, and the treatment concentration was 100 times solution and 1,000 times solution level with foliar application. The results are summarized as follows: Among foliar application of organic materials treatment plot[?], with 1,000 times solution level of chitosan was effective in inhibiting microbial growth in Chinese cabbage compared to other plots and control. The microorganism number in the soil for cultivation of Chinese cabbage increased with organic materials treatment plot as compared with control. Especially, 1,000 times solution level of chitosan showed the most significant effect.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.1
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• pp.21-28
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• 2018

The contents of total nitrogen, total phosphate, and total potash are important factors to determine the application rate of the organic fertilizers to arable lands. The concentrations of nutrient, organic matter, salt, water, heavy metal in mixed oil cakes and mixed organic fertilizers in circulation were investigated with 141 and 179, respectively. The mean levels of total nitrogen, total phosphate, and total potash in organic fertilizers of from 2015 to 2017 were 4.9%, 2.8%, 1.7%, respectively. The average contents of organic matter, salt, and water were 77.0%, 11.5%, and 0.3%, in mixed oil cakes, and 72.3%, 11.7%, 0.5% in mixed organic fertilizer, respectively. The maximum concentrations of Cr, Cu, Ni, and Zn were found to be in accordance with the official standard of commercial fertilizer. In order to promote balanced nutrient absorption of crops, it is necessary to increase the average content of total potash of the organic fertilizers to 3.2%.