• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.126-132
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• 2013

The objectives of this study were to provide the basic data of the residue of deltamethrin in the stream water. Deltamethrin was treated on side of Ban-Suk stream and Juk-Dong ditch for hygienic purpose by air spray. The drift concentration of deltamethrin was investigated with different wind speed condition on Ban-Suk stream (A), and the change of residue with time course on Juck-dong ford (B). Also we found the residual change of deltamethrin until 48 hour in Yu-Seong stream confluence (C) where two streams join. Maximum residues of A were $0.17{\mu}g/L$ (5 min, 200 m) at strong wind speed and $4.42{\mu}g/L$ (0 min, 25 m) at moderate wind speed according to different wind velocity. Residues of B were $0.15{\sim}0.26{\mu}g/L$ (0~480 min) after spraying, and decreased to a non-detected level after 720 min. Residues of C were $0.15{\mu}g/L$ (0 min), $0.11{\mu}g/L$ (1 min) and $0.10{\mu}g/L$ (12 hr) after spraying, and no residues were detected in any other samples. From these results, it is concluded that deltamethrin residues in water should be rapidly diluted into stream water and affected negligible toxic effect to stream ecosystem.

• Korean journal of applied entomology
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• v.56 no.3
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• pp.301-308
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• 2017

Locusts, Locusta migratoria (Orthoptera: Acrididae) are periodical unpredictable agricultural pests worldwide and cause serious damage to crop production; however, little consideration has been given to the management of this pest. Herein, we constructed a locust-pathogenic fungal library and confirmed that some fungi could be used as resources for locust management. First, the entomopathogenic fungi were collected from sampled soils using a Tenebrio molitor-based baiting system. For the locust assay, a locust colony was obtained from the National Institute of Agricultural Science and Technology. A total of 34 entomopathogenic fungal granules, which were produced by solid cultures, were placed in the plastic insect-rearing boxes (2 g/box) and nymphs of locust were contained in the box. In 3-7 days, mycosis was observed on the membranous cuticles of the head, abdomen, and legs of locusts. In particular, Metarhizium anisopliae, M. lepidiotae, and Clonostachys rogersoniana exhibited high virulence against the locust. Given that the 34 isolates could be used in field applications, their conidial production and stability (thermotolerance) were further characterized. In the thermotolerance assay, Paecilomyces and Purpureocillium isolates had higher thermotolerance than the other isolates. Most of the fungal isolates produced ca. >$1{\times}10^8conidia/g$ on millet grain medium. In a greenhouse trial, the granular application of M. anisopliae isolate on the soil surface resulted in 85.7% control efficacy. This work suggests that entomopathogenic fungi in a granular form can be effectively used to control the migratory locust.

• Tuberculosis and Respiratory Diseases
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• v.52 no.3
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• pp.219-229
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• 2002

Background : Sepsis-induced acute lung injury (ALI) is caused by many cellular and humoral mediators induced by an endotoxin. Histamine, which is widely distributed in the lungs and has been considered as an important mediator of sepsis. It increases P-selectin expression on the endothelial cell surfaces and induces IL-8 secretion. Therefore, an endotoxin-induced histamine may be related to neutrophil-mediated ALI by inducing the migration and activation of neutrophils in the lung tissue. However, the role of endogenous histamine in endotoxin ALI has not been clarified. The purpose of this study was to investigate how endotoxin-induced ALI is influenced by endogenous histamine and to identify the possible mechanism of action. Materials and Methods : The study consisted of 4 groups using Sprague-Dawley rats : 1) control group, where the rats were infused intratracheally by normal saline, 2) an endotoxin group, where lipopolysaccharide (LPS) was administered intratracheally 3) the $H_2$ receptor antagonist-treated group ($H_2$ group) and 4) the $H_1$ receptor antagonist-treated group ($H_1$ group), where $H_2$-receptor blocker (ranitidine) and $H_1$-receptor blocker(pyrilamine) were co-treated intravenously with the intratracheal administration of an endotoxin. The lung leak index using $I^{125}$-BSA, the total protein and LDH concentration in the lung lavage fluid, myeloperoxidase(MPO) activity in the lung tissue, the pathologic score and the total number of neutrophils, TNF-$\alpha$, IL-$1{\beta}$ and IL-10 in lung lavage (BAL) fluid were measured in each group as the indices of lung injury. Results : Compared to the control group, the endotoxin group exhibited significant increases in all lung injury indices. Significant reductions in the endotoxin-mediated increases in lung leak index (p<0.05) were observed in both the $H_1$ and $H_2$ groups. In addition the total protein (p<0.05) and LDH concentration (p<0.05) in the BAL fluid were also lower in the $H_2$ group compared to the endotoxin group. However, there was no change in the MPO activity in the lung tissue, the pathologic score and the total number of neutrophils in the BAL fluid in both the $H_2$ and $H_1$ groups compared to the endotoxin group. The increases in TNF-$\alpha$ IL-$1{\beta}$ and IL-10 concentrations in the BAL fluid observed in the endotoxin group were not reduced in the $H_2$ and $H_1$ groups. Conclusion : Antihistamine attenuated the enhanced alveolar-capillary permeability induced by the endotoxin via the $H_2$ receptor. However the attenuating mechanism may not be related to the pathogenesis of neutrophil dependent lung injury.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.582-600
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• 2007

In a long history of geography, a variety of regional concepts have been suggested to represent the particular situations in each period. Today, post-modem situations, characterized by the development of capitalism and globalization, demand a new variety of regional concepts. The regional characteristics, such as social relations, institutional systems, ideologies and symbolism, are now perceived basically on the level of subjectivity. Currently, it is the most urgent task to integrate many conflicting opinions among a variety of subjects into the one that would seek a voluntary consent from the majority of regional residents. In this paper, it is suggested that the concept of identity is the most efficient in examining and explaining the post-modem trend of a region: variability, subjectivity, mobility, changeability, Finally, it is suggested that a special attention should be paid to the role of institutions, that is institutionalization, in the construction of regional identity, to understand and interpret the cultural-historical aspect of a regional change.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1243-1252
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• 2009

We investigated a method to improve anticancer activities of Acer mono by ultra high pressure extraction process. The extract yields by ultra high pressure were 9.49% and 9.87% for 5 min and 15 min processing time, respectively, which were relatively higher than 3$\sim$4% of conventional extraction processes due to their resid bark structure. The extract for 15 minutes extraction (HPE15) showed higher potent scavenging effect as 94.56% than the control, BHA as 93.24%. On SOD-like test, HPE15 also showed the highest activity as 38.6% at 1.0 mg/mL concentration. The cytotoxicity of HPE15 on normal human lung and kidney cell were below 23.54% in adding 1.0 mg/mL. Generally, human cancer cell growth stomach adenocarcinoma (AGS), lung adenocarcinoma (A549), breast adenocarcinoma (MCF-7), colon adenocarcinoma (Caco-2) and liver adenocarcinoma (Hep3B) were inhibited up to 75% with higher selectivity of above 4.0. High antioxidant activity of HPE15 resulted in high anticancer activity, and its activity was also due to higher yields of Acer mono by ultra high pressure extraction process. It was also proved by HPLC comparison analysis.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.462-474
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• 1994

Background : In acute lung injury, activated neutrophils play an important role in tissue damage. For neutrophils to participate in lung inflammation, chemotactic factors released from mononuclear phagocytes are needed to bring these cells to the local site of inflammation, with interleukin-8 (IL-8) being one of the most specific and important chemotactic factors for neutrophils. IL-8 also induces the expression of adhesion molecules and activates neutrophils to release various inflammatory mediators. Lipopolysaccharide(LPS) is one of the most important causes of adult respiratory distress syndrome and can cause release of many inflammatory cytokines including IL-8 leading to acute lung injury. But little is known about the regulatory mechanism of LPS-induced IL-8 gene expression in mononuclear phagocytes. Method : Human alveolar macrophages(HAM) and peripleral blood monocytes(PBMC) were isolated from healthy volunteers. Time and dose relationship of LPS-induced IL-8 mRNA expression was observed by Northern blot analysis. To evaluate the regulatory mechanism of LPS-induced IL-8 gene expression, pretreatment of actinomycin D(AD, $5{\mu}g/ml$) and cycloheximide(CHX, $5{\mu}g/ml$) was done and Northern blot analysis for IL-8 mRNA and ELISA for immunoreactive IL-8 protein in culture supernatant were performed. Results : 1) In HAM, dose and time dependent LPS-induced IL-8 mRNA expression was observed with peak mRNA level at 8 hours post-stimulation. 2) In PBMC, dose and time dependent LPS-induced IL-8 mRNA expression was also observed with peak mRNA level at 4 hours post-stimulation. 3) AD decreased expression of LPS-induced IL-8 gene expression at both mRNAand protein levels in both types of cells. 4) CHX decreased expression of LPS-induced IL-8 gene expression at protein level in both cell types but in HAM, superinduction of IL-8 mRNA was observed while decreased expression of IL-8 mRNA was observed in PBMC. Conclusion : Time and dose dependent LPS-induced IL-8 gene expression was observed in mononuclear phagocytes which is at least partly regulated pretranslationally. LPS-induced IL-8 mRNA expression in HAM needs no de novo protein synthesis and may be under the control of a labile repressor protein while de novo protein synthesis may be needed in PBMC.

• Progress in Medical Physics
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• v.26 no.4
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• pp.208-214
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• 2015

The aim of this study is to investigate the effect of low magnetic field on dose distribution in the partial-breast irradiation (PBI). Eleven patients with an invasive early-stage breast carcinoma were treated prospectively with PBI using 38.5 Gy delivered in 10 fractions using the $ViewRay^{(R)}$ system. For each of the treatment plans, dose distribution was calculated with magnetic field and without magnetic field, and the difference between dose and volume for each organ were evaluated. For planning target volume (PTV), the analysis included the point minimum ($D_{min}$), maximum, mean dose ($D_{mean}$) and volume receiving at least 90% ($V_{90%}$), 95% ($V_{95%}$) and 107% ($V_{107%}$) of the prescribed dose, respectively. For organs at risk (OARs), the ipsilateral lung was analyzed with $D_{mean}$ and the volume receiving 20 Gy ($V_{20\;Gy}$), and the contralateral lung was analyzed with only $D_{mean}$. The heart was analyzed with $D_{mean}$, $D_{max}$, and $V_{20\;Gy}$, and both inner and outer shells were analyzed with the point $D_{min}$, $D_{max}$ and $D_{mean}$, respectively. For PTV, the effect of low magnetic field on dose distribution showed a difference of up to 2% for volume change and 4 Gy for dose. In OARs analysis, the significant effect of the magnetic field was not observed. Despite small deviation values, the average difference of mean dose values showed significant difference (p<0.001), but there was no difference of point minimum dose values in both sehll structures. The largest deviation for the average difference of $D_{max}$ in the outer shell structure was $5.0{\pm}10.5Gy$ (p=0.148). The effect of low magnetic field of 0.35 T on dose deposition by a Co-60 beam was not significantly observed within the body for PBI IMRT plans. The dose deposition was only appreciable outside the body, where a dose build-up due to contaminated electrons generated in the treatment head and scattered electrons formed near the body surface.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.4
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• pp.113-117
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• 2016

Recently, hydrogen is regarded as important energy in the future, because it is clean and renewable. The photoelectrochemical (PEC) system, which produce hydrogen using water splitting by solar energy, is one of the most promising energy systems because it has abundant energy sources and good theoretical efficiency. GaN has recently been regarded as suitable photoelectrode that could be used to split water to generate hydrogen without extra bias because its band edge position include water redox potential ($V_{redox}=1.23$ vs. SHE). GaN also shows considerable corrosion resistance in aqueous solutions and it is possible to control its properties, such as structure, band gap, and catalyst characteristics, in order to improve solar energy conversion efficiency. But, even if the band edge position of GaN make PEC reaction facilitate without bias, the overpotential of oxygen evolution reaction could reduce the efficiency of system. One of the ways to decrease overpotential is introduction of co-catalyst on photoelectrode. In this paper, we will investigate the effect of manganese dioxide ($MnO_2$) as a co-catalyst. $MnO_2$ particles were dispersed on GaN photoelectrode by spincoater and analyzed properties of the PEC system using potentiostat (PARSTAT4000). After coating $MnO_2$, the flat-band potential ($V_{fb}$) and the onset voltage ($V_{onset}$) were moved negatively by 0.195 V and 0.116 V, respectively. The photocurrent density increased on $MnO_2$ coated sample and time dependence was also improved. These results showed $MnO_2$ has an effect as a co-catalyst and it would enhance the efficiency of overall PEC system.

• Economic and Environmental Geology
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• v.40 no.2 s.183
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• pp.209-221
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• 2007

Numerical analysis was performed to investigate the effect of heavy metal contamination on neighboring environment in case a dam is constructed by using rockfill materials contaminated by heavy metals. The numerical simulation carried out in this research includes both subsurface flow and contaminant transport in the inside of the CFRD(Concrete Faced Rockfill Dam), using two commercial programs, SEEP2D and FEMWATER. The three representative cases of scenarios were chosen to consider a variety of cases occurring in a dam site; (1) Scenario 1 : no crack in the concrete face slab, (2) Scenario 2 : a crack In the upper part of face slab, and (3) Scenario 3 : a crack between plinth and face slab in the lower part of face slab. As a result of seepage analysis, the amount of seepage in scenario 2 was calculated as $14.31\sim14.924m^3/day$ per unit width, corresponding to the 1,000 times higher value than that in other scenarios. Also, in the simulation of contaminant transport by using FEMWATER, specified contaminant concentration of 13 ppb in main rockfill zone was set to consider continuous leakage from the rock materials. Through the analysis of contaminant transport, we found that elapsed times to take for the contaminant concentration of about 2 ppb to arrive at the end of a dam are as follows. Scenario 1 has the elapsed time of 55,000 years. In Scenario 2. it is 50 years. Finally, scenario 3 has 27,000 years. The rapid transport of the contaminant in scenario 2 was attributed to greater seepage flow by 500 times than other scenarios. Although, in case of upper crack in the face slab, it was identified that the contaminant might transport to the end of a dam within 100 years with about 2 ppb concentration, however, it happened that the contaminant was hardly transported out of the dam in other scenarios, which correspond to either no crack or a crack between plinth and face slab. In conclusion, the numerical analysis showed that the alternative usage of the contaminated sand and gravel as the dam embankment material can be one of the feasible methods with the assumption that the cracks in a face slab could be controlled adequately.

• Economic and Environmental Geology
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• v.47 no.2
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• pp.87-96
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• 2014

The objectives of this study were to characterize the physicochemical properties and mineralogy of Hwangto (yellow residual soils) from the southwestern part of Korea and to understand the soil-forming processes of the residual soils from their parent rocks. Both the yellowish residual soils as well as the unweathered and weathered parent rocks were obtained from Jangdong-ri, Donggang-myun, Naju, Jeollanam-do, Korea. The soil samples were examined to analyze the said soil's physicochemical properties such as color, pH, and particle size distribution. A scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis were performed in order to understand the mineralogy, chemical composition, and morphology of the soils. Two thin sections of a parent rock were analyzed to study its mineral composition. A particle size analysis of the soils indicates that the residual soil consists of mainly silt and clay (approximately 95%) and that soil textures are silty clay or silt clay loam. The soil colors of the residual soil are dark brown (7.5YR 3/4) through yellowish red (5YR 4/6). The pH of the residual soil ranges from 4.3 to 5.1. The major minerals of the parent rocks were quartz, biotite, chlorite, and plagioclase. The mineralogy of the sand fraction of the residual soil was quartz, biotite, muscovite and sanidine. The mineralogy of the silt fraction of the residual soil was quartz, biotite, muscovite, Na-feldspar, K-feldspar, and sanidine. The clay mineralogy of the soil was goethite, kaolinite, ilite, hydroxy-interlayed vermiculite(HIV), vermiculite, mica, K-feldspar and quartz. The mineral composition of the residual soil and the parent rock indicates that feldspar and mica in the parent rock weathered into illite, vermiculite and hydroxy-interlayed vermiculite(HIV), and finally changed into kaolinite and halloysite in the yellowish residual soils.