• Environmental Analysis Health and Toxicology
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• v.7 no.3_4
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• pp.17-35
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• 1992

In this study, it was examined the toxic effects of combination of buprofezin and carbaryl on hematological, biological and enzymetic parameters in rats. The administration of buprofezin or carbaryl both induced the tissue content of cytochrome P-450 and furthermore, the combination of the both increased significantly the liver content of cytochrome P-450 in rat. But cytochrome P-450 and NADPH -cytochrome c reductase activities in kidney were slightly increased. Administration of carbaryl and combination of the both also significantly increased hepatic aniline hydroxylase activity. In addition, in the combination group, glucose-6-phosphatase and lipid peroxidase activities were changed in the rat liver. Furthermore, cholinesterase was inhibited in rats treated with carbaryl or the combination of buprofezin and carbaryl. The above results suggested that the combined administration of buprofezin and carbaryl can induce more toxic effects than the single administration of buprofezin or carbaryl.

• Journal of Environmental Health Sciences
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• v.40 no.4
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• pp.294-303
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• 2014

Objectives: Excretion and tissue distribution of titanium oxide nanoparticles were evaluated in rats after oral administration. The relation between toxicity and systemic concentration of nanoparaticles was investigated. Methods: Rats were orally treated with titanium oxide nanoparticles (10, 100 mg/kg) for five consecutive days. General toxicity, blood chemistry, and serum biochemical analysis were analyzed. Titanium concentration in liver, kidney, lung, urine and feces were measured and histopathology was performed in these organs. Results: Induction of toxicological parameters was not observed and titanium nanoparticles were excreted via feces. Conclusion: Absorption of titanium oxide nanoparticles via the gastrointestinal tract after oral administration was very poor and systemic concentration of titanium oxide nanoparticles was not elevated. Titanium oxide nanoparticles did not cause toxicities in rats after oral administration.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2018.10a
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• pp.246-246
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• 2018

• Environmental Mutagens and Carcinogens
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• v.25 no.1
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• pp.1-5
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• 2005

The present work was undertaken to evaluate the antimetastatic potential of capsaicin (8­methyl-N-vanillyl-6-nonenamide) by measuring its effects on matrix metalloproteinase activity, cell invasion and lung metastasis. Significant inhibition of matrix metalloproteinase-2 activity by capsaicin (100 $\mu$M) was detected by gelatin zymography. In vitro invasion assay showed capsaicin (50, 100 $\mu$M) reduced tumor cell invasion ($28-40\%$). Capsaicin (i.p., 2.5 mg/kg) inhibited development of lung colonization ($58\%$). These results suggest that capsaicin prevents metastasis in part through suppression of invasion of B16F10 melanoma cells by inhibiting matrix metalloproteinase-2 responsible for degradation of extracellular matrix.

• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.1-7
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• 2006

This study was conducted to develop a system and an control algorithm for control the environment of a plant factory. The greenhouse control system for environmental control was largely composed of a computer and a PLC. The screen of control program was composed of a greenhouse figure which was included machinery and equipments for greenhouse, the graph of environmental factors of inside greenhouse and the image of greenhouse. In order to reduce temperature change, the operation time of ventilation window was changed by 3 stage according to difference between a target and present temperature. When is heating, a temperature variation was shown to be $16.7{\pm}0.8^{\circ}C$. When is cooling, a temperature variation was shown to be $23.1{\pm}0.6^{\circ}C$. When is humidifing, a humidity variation was shown to be $39.3{\pm}1.6^{\circ}C$ %RH. An environmental control system and a control algorithm were proved that it was shown a good performance in a control accuracy. So a computer control system should be adapted to a control system of a greenhouse and a plant factory.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.2
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• pp.383-393
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• 2022

At present, environmental problems are gradually becoming quite serious because of the expansion of the business scale of companies, factories, and enterprises, and that is also the reason for the global pollution of the world. Green entrepreneurship is playing an increasingly crucial role in influencing people's intentions, behaviors, and attitudes toward environmental protection through sustainable development. The purpose of this research was to examine the factors affecting university students' green entrepreneurship levels in Vietnam. To do this, we performed a scientific research survey with 773 students from reputable universities in Vietnam, 337 of whom are male and 436 of whom are female. To assess the reliability and correlation between observed and total variables, this study employs scale testing methods such as Cronbach alpha, EFA, CFA, and SEM. After evaluating the influencing elements, the findings reveal that the Subjective norm factor and the Risk-aversion component are two distinct aspects that influence university students' green entrepreneurship intentions in Vietnam and of which, the greatest influence is Risk Aversion. Furthermore, the findings revealed that the level of interest in green entrepreneurship is mostly seen by students with university education between the ages of 18-25.

• Journal of Environmental Science International
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• v.15 no.1
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• pp.85-94
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• 2006

The simultaneous analysis of multi-residual pesticides was developed using a gas chromatography (GC) method. In this study, a simple and reliable methodology was improved to detect 154 kinds of pesticides in sinseng extract sample by using a liquid-liquid extraction procedure, open column chromagraphy and chromatographic analysis by CC electron capture detector (ECD) and GC nitrogen-phosphorus detector (NPD). The 154 kinds of pesticides were classified in 4 groups according to the chemical structure. The extraction of pesticides was experimented with $70\%$ acetone and dichloromethane/petroleum ether in order, and cleaned up via open column chromatography $(3\times30cm)$ packed with florisil $(30g,\;130^{\circ}C,\;12hrs)$. The final extract was concentrated in a rotator evaporator at $40^{\circ}C$ until dryness. Then the residue was redissolved to 2ml with acetone, and analyzed by GC-ECD and GC-NPD. The applied concentration of pesticides was over $1\~10{\mu}g/ml$. The recovery tests were ranged from $70.7\%$ to $115.2\%$ with standard deviations between 0.3 and $5.7\%$ of the standard spiked to the ginseng extract sample (Group $I\~IV$). The limit of detection (LOD) ranged from 0.001 to $0.099{\mu}g/ml$ (Group $I\~IV$). The 9 kinds of pesticides were not detected. The developed method was applied satisfactory to the determination of the 154 kinds of pesticides in the ginseng extract with good reproducibility and accuracy.

• The Plant Pathology Journal
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• v.17 no.4
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• pp.231-235
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• 2001

From April to May 1998, Phytophthora rot on pear, which has not been reported in Korea before, became an epidemic in the southeast part of the country under abnormally higher temperature and prolonged rainy days. Average temperature was about $3^{\circ}$ higher than in normal years, and 29 days were rainy during the 2 months in the areas surveyed. Over 1,000 orchards estimated at about 270 ha in 19 cultivation areas were infected by the disease, which occurred on all parts of the tree such as leaves, shoots, branches, stems, and flower clusters. Among 43 isolates collected from various locations and plant parts, 41 were identified as Phytophthora cactorum while 2 were identified as P. cambivora based on their mycological characteristics. The representative isolates revealed strong pathogenicity not only to pear but also to apple and peach. Among 23 pear cultivars tested, 7 were estimated as susceptible, 4 were moderate, and 11 were resistant to the pathogen. Results suggest that Phytophthora disease on pear is a potential threat to pear cultivation when environmental factors are favorable to disease development.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.1-7
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• 2003

Environmental changes caused by the abrupt climatic change are one of the important issues in the scientific community. In the East Sea, abrupt climatic shift, called Younger Dryas, is identified. The age of the Younger Dryas cold episode occurred at 11.2 ka. Overall, changes in circulation and bottom water conditions occurred during the Younger Dryas cold episode in the study area. Especially, climatic transition from meltwater spike to the Younger Dryas cold episode is characterized by significant shifts of oxygen isotope values, the coiling ratios of Neogloboquadrina pachyderma, and the planktonic foraminifers abundances. The impact of abrupt climate change on the ecosystem is very significant. In the East Sea, the calcium carbonate secreting organism(foraminifers) is replaced by silicon dioxide secreting organisms(diatom, radiolarian) after the abrupt and severe cold climatic event. Based on the Doctrine of Uniformitarianism, at least climate change for the next 100 years would be severely influence on the marine ecosystem.

• Bulletin of Korea Environmental Preservation Association
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• v.20 no.9_10
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• pp.24-28
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• 1998