• Toxicological Research
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• v.29 no.3
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• pp.211-215
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• 2013

The trace toxic metal copper was assayed using mercury immobilized on a carbon nanotube electrode (MCW), with a graphite counter and a reference electrode. In this study, a macro-scale convection motor was interfaced with a MCW three-electrode system, in which a handmade MCW was optimized using cyclic- and square-wave stripping voltammetry. An analytical electrolyte for tap water was used instead of an expensive acid or base ionic solution. Under these conditions, optimum parameters were 0.09 V amplitude, 40 Hz frequency, 0.01 V incremental potential, and a 60-s accumulation time. A diagnostic working curve was obtained from 50.0 to 350 ${\mu}g/L$. At a constant Cu(II) concentration of 10.0 ${\mu}g/L$, the statistical relative standard deviation was 1.78% (RSD, n = 15), the analytical accumulation time was only 60 s, and the analytical detection limit approached 4.6 ${\mu}g/L$ (signal/noise = 3). The results were applied to non-treated drinking water. The content of the analyzed copper using 9.0 and 4.0 ${\mu}g/L$ standards were 8.68 ${\mu}g/L$ and 3.96 ${\mu}g/L$; statistical values $R^2$ = 0.9987 and $R^2$ = 0.9534, respectively. This method is applicable to biological diagnostics or food surveys.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.2
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• pp.137-140
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• 1995

The pufferfish Takifugu obscurus (hwang-bok) was examined for toxicity. Forty-six specimens, which had Gaught at the Imjin River in 1992 and 1993, Korea, were collected and assayed for anatomical distribution of toxicity by the mouse assay method. Ovary and liver showed very strong toxicity, testis, intestine, gall bladder and spleen did moderate toxicity, muscles and skin did weak toxicity, and blood was non-toxic. The results of this study were different from those of Tani, who had examined the toxicity in 19 species of pufferfish, in terms of toxicity in testis, muscle, and skin. The toxicity of testis and muscle had been known to be non-toxic or weakly toxic previously, however, they were known to have weak or moderate toxicity. Therefore, careful attention should be taken to prevent food poisoning by pufferfish ingestion.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.325-334
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• 2012

It has been known that endophyte (Neotyphodium coenophialum) is beneficial to tall fescue (Schedonorus phoenix Scop.) because the mutualistic endophyte is able to confers tolerance against abiotic and biotic stresses to tall fescue. However, this fungal endophyte produces toxic alkaloid resulting in negative effects on animal performance. Recently, Non-toxic endophyte have been developed and inserted into tall fescue to avoid detrimental effect on animal but remaining positive influence on tall fescue. In order to keep this beneficial impact, it is essential to have endophyte infected tall fescue through vertical transmission from maternal plants to seeds. Little research has been carried out on endophyte transmission. To get basic information related to endophyte transmission, experiment was conducted to examine the effect of plant genotype on endophyte transmission under water stresses. Overall endophyte concentration in seeds was higher than that in panicles and endophyte concentration in seeds and panicles relied on plant. This study revealed that drought is not a critical component to control the endophyte transmission from maternal plants to seeds. Plant genotype is an important factor controlling the endophyte transmission from plant to seed.

• Journal of the Korean Society of Safety
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• v.38 no.6
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• pp.60-71
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• 2023

The purpose of this study is to propose a quantitative toxicity endpoint distance suitable for the initial response of firefighters by comparing and analyzing the commonly applied toxic level of concern (T-LOC), specifically emergency response planning guidelines (ERPG), acute exposure guideline levels (AEGL), and immediately dangerous to life or health (IDLH). This is to protect the fire brigade, which responds to toxic chemical accidents first during the golden time. Using areal locations of hazardous atmospheres, a damage prediction program, the amount of leakage for both acidic and basic substances, along with the endpoint distance, were analyzed for alternative accident and worst-case accident scenarios. The results showed that the toxicity endpoint distance, serving as a compromise between Level-3 and Level-2 of T-LOC, was longer than ERPG-3 and shorter than ERPG-2 with IDLH, while its values were analyzed in the order of ERPG-2, AEGL-2, IDLH, AEGL-3, and ERPG-3. It is suggested that the application of IDLH in an emergency (red card) and ERPG-2 endpoint distance in a non-emergency (non-red card) can be utilized for the initial response of the fire brigade.

• 대한예방의학회:학술대회논문집
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• 1994.02a
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• pp.412-415
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• 1994

The fundamental assumption that thresholds exist for noncarcinogenic toxic effects of chemicals is reviewed; this assumption forms the basis for the no-observed-effect level/ safety-factor (NOEL/SF) approach to risk assessment for such effects. The origin and evolution of the NOEL/SF approach are traced, and its limitations are discussed. The recently proposed use of dose-response modeling to estimate a benchmark dose as a replacement for the NOEL is explained. The possibility of expanding dose-response modeling of non carcinogenic effects to include the estimation of assumed thresholds is discussed. A new method for conversion of quantitative toxic responses to a probability scale for risk assessment via dose-response modeling is outlined.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.986-990
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• 2003

The living Glass puffers, Takifugu niphobles (Bogseom as Korean name), 10 specimens, were purchased at Tongyeong traditional fisheries market every month from November, 2001 to October, 2002, and tested anatomical distribution of the toxicity such as muscle, skin, intestine, liver and ovary by mouse bioassay method. Significant seasonal variations of the toxicity were not shown in muscle, skin, intestine and liver except having lower toxicity in spawning season (May and June) than non-spawning seasons. 92 specimens (76.7%) out of 120 ones were non toxic (below 10 MU/g) for the edible and 28 ones (23.3%) were weakly toxic (10 MU/g∼l00 MU/g) for the non-edible in muscle ranged between 0 MU/g and 46.4 MU/g. All of those toxicity were shown over 10 MU/g in skin for the non-edible in skin ranged from 10.0 MU/g to 674.4 MU/g. Toxicity range in intestine and liver was varied between non-toxic and strongly toxic (over 1,000 MU/g) for individual specimens. Toxicity range of the ovary found only in May (7 specimens) and June (1 specimens) was 84.2 MU/g to 2,191.3 MU/g.

• Journal of the Korean Chemical Society
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• v.52 no.3
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• pp.257-265
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• 2008

The synthesis, characterization and bioevaluation of five new tetrahydroquinazolines was reported. Initially cyclohexanones were prepared and they were used as synthons to get the target molecules. These were condensed with substituted benzaldehydes and the resulting chalcones were treated with guanidine hydrochloride . All the molecules were non-toxic to human cells and showed significant antibacterial activity.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.4
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• pp.185-193
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• 2002

With Increasing awareness towards environment-friendly and non-toxic pesticide azadirachtin obtained from neon tree (Azadirachta indica) is gaining more and more importance. Its broad-spectrum activity, Peculiar mode of action. eco-friendly and non-toxic action towards beneficial organisms has offered many advantages over chemical pesticides. All currently use commercial formulations based on azadirachtin contains azadirachtin extracted from seeds of naturally grown whole plants which is labour intensive process depending upon many uncontrollable geographical and climatic factors. Plant tissue culture can be a potential process for the pro-duction, offering consistent, stable and controlled supply of this bioactive compound, However the research on tissue culture aspects of production are in preliminary stage and requires culture and process optimization for the development of a commercially viable process. This review states the present status and future challenges of plant tissue culture for azadirachtin production.

• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.3
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• pp.105-112
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• 2002

A combined process of non-thermal plasma and catalytic techniques has been investigated to treat toxic gas compounds in air. The treated gas in the present study is $CH_3$CN that has been known to be a simulant of toxic chemical agent. A planar type dielectric barrier discharge(DBD) reactor has been used to generate non-thermal plasma that produces various chemically active species, O, N, OH, $O_3$, ion, electrons, etc. Several different types of adsorbents and catalysts, which are MS 5A, MS 13X, Pt/alumina, are packed into the plasma reactor, and have been tested to save power consumption and to treat by-products. Various aspects of the present techniques, which are decomposition efficiencies along with the power consumption, by-product analysis, reaction pathways modified by the adsorbents and catalysts, have been discussed in the present study.

• Journal of the Korean Society of Safety
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• v.13 no.3
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• pp.96-101
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• 1998

In order to study the change in mechanical properties and anti-flammablilty of ethylene-ethylacrylate copolymer(EEA) very low density polyethylene(VLDPE) compound that could be used as communication cable sheath using $Mg(OH)_2$ as a non-toxic flame retardant, 100, 125, and 150phr $Mg(OH)_2$ were added to 100 parts of EEA-VLDPE compound, 100 EEA : 0 VLDPE, 50 EEA : 50 VLDPE, and 0 EEA : 100 VLDPE, respectively. $Mg(OH)_2$ was a good non-toxic flame retardant for communication cable sheath and anti-flammability increased with the amount of $Mg(OH)_2$ in compound. The mechanical properties-MI, Ts, and Eb-decreased with increasing in the mixing ratio of EEA but oxygen index(OI) increased with increasing in the amount of EEA. The best composition of $Mg(OH)_2$ in this study was 150phr to 50 EEA : 50 VLDPE compound for the anti-flammability.