• Journal of the Korean Electrochemical Society
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• v.13 no.2
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• pp.145-152
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• 2010

The gel polymer electrolyte(GPE) were prepared by in-situ thermal cross-linking reaction of homogeneous precursor solution of perfluorinated phosphate-based cross-linker and liquid electrolyte. Ionic conductivities and electrochemical properties of the prepared gel polymer electrolyte with the various contents of liquid electrolytes and perfluorinated organophosphate-based cross-linker were examined. The stable gel polymer electrolyte was obtained up to 97 wt% of the liquid electrolyte. Ionic conductivity and electrochemical properties of the gel polymer electrolytes with the various chain length of perfluorinated ethylene oxide and different content of liquid electrolytes were examined. The maximum ionic conductivity of liquid electrolyte was measured to be $1.02\;{\times}\;10^{-2}\;S/cm$ at $30^{\circ}C$ using the cross-linker($PFT_nGA$). The electrochemical stability of the gel polymer electrolyte was extended to 4.5 V. The electrochemical performances of test cells composed of the resulting gel polymer electrolyte were also studied to evaluate the applicability on the lithium polymer batteries. The test cell carried a discharge capacity of 136.11mAh/g at 0.1C. The discharge capacity was measured to be 91% at 2C rate. The discharge capacity decreased with increase of discharge rate which was due to the polarization. After 500th charge/discharge cycles, the capacity of battery decreased to be 70% of the initial capacity.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.54-63
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• 2015

Streptomyces spp. isolated from turfgrass rhizosphere and tested for their response to large-patch control fungicides. The tested fungicides were actually used in golf course or turfgrass cultivation to prevent large-patch disease. Tolerance to 3 triazole group of the strains was the highest to the PR fungicide, and following the SR fungicide, whereas the isolated strains were no tolerance to HR fungicide. Tolerances to three kind of Strobilurin group were similar for the all of the tested Streptomyces spp.. Growth and sporulation of the all strain was normal in CB and AP fungicide treatments. However no spore formulated in double concentration. Strains, tolerance to acetanilide fungicides, appeared that KT fungicide tolerance was higher than MK fungicide. The selected strains showed strong tolerance against AT fungicide but have no tolerance to ATR fungicides. In conclusion, the bacterial strains showed tolerance against 1 carbamate, 1 organophosphate and 1 cyanopyrrole group, while have no tolerance against two mixture formulations (1 Quinone + Strobilurin and 1 Imidazole + Triazole).

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.171-178
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• 2007

Esterase isozymes were extracted from final instar larvae of M. saltuarius treated with selective diets and inhibitors. Twenty esterase isozymes were separated on 12% native-PAGE gel and stained with three different substrates(${\alpha}$-naphthyl acetate, ${\beta}$-naphthyl acetate, or ${\alpha}$-naphthyl butyrate). Interestingly, the isozymes of Est7(${\alpha}$-naphthyl acetate and ${\alpha}$-naphthyl butyrate) and Est6(${\beta}$-naphthyl acetate) were specifically activated in final instar larvae fed with the bark of Pinus koraiensis. However, we could not find any band from substrate ${\beta}$-naphthyl stearate. The esterase activities of Est3, Est6, and Est7 were inhibited by organophosphate and carbamate insecticides. In addition, The esterase activities of Est4, Est6, and Est7 were also inhibited by eserine. However, inhibition of esterase activities in methoprene, bornyl acetate, linal, cineol, and citral was not observed. However, It is necessary to reconfirm these results in vivo.

• Journal of The Korean Society of Clinical Toxicology
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• v.12 no.2
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• pp.77-84
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• 2014

Purpose: Carbamate insecticides are potent cholinesterase inhibitors capable of causing severe cholinergic toxicity. Use of carbamate rather than organophosphate insecticides has been increasing. Compared with organophosphate poisoning, relatively few studies have investigated carbamate-associated acute pancreatitis. We investigated general characteristics and pancreatitis of carbamate poisoning and the predictors, among those readily assessed in the emergency department. Methods: We performed a retrospective review of consecutive patients, aged over 18 years, who were admitted between January 2008 and April 2012 to an emergency department (ED) of an academic tertiary care center for treatment of carbamate poisoning. Patients who exhibited poisoning by any other material, except alcohol, were excluded. After application of exclusion criteria, patients were divided according to carbamate-induced pancreatitis and non-pancreatitis groups. Results: A total of 41 patients were included in this study. Among these 41 patients, the prevalence of acute pancreatitis was 36.6% (15 patients). Initial blood chemistry tests showed a statistically higher glucose level in the pancreatitis group, compared with the non-pancreatitis group (222, IQR 189-284 vs. 137, IQR 122-175 mg/dL, P<0.05). Regarding clinical courses and outcomes, a significantly higher proportion of patients developed pneumonia [10 (66.7%) vs. 6 (23.1%), P<0.05] and had a longer hospital stay (7 days, IQR 6-12 vs. 5 days, IQR 2-11, P<0.05), but no difference in mortality, in the pancreatitis group vs. the non-pancreatitis group. In multivariate analysis, the initial glucose was showing significant association with the presentation of carbamate-induced acute pancreatitis (odds ratio 1.018, 95% confidence interval 1.001-1.035, P<0.05). Conclusion: Carbamate-induced acute pancreatitis is common, but not fatal. Initial serum glucose level is associated with acute pancreatitis.

• Korean journal of applied entomology
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• v.61 no.4
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• pp.519-528
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• 2022

The western flower thrips, Frankliniella occidentalis, infests the hot pepper cultivated in greenhouses and has been considered to be controlled by a natural enemy, Orius laevigatus. However, sporadic outbreaks of the thrips due to fast population growth occasionally need chemical insecticide treatments. This study was designed to develop an optimal integrated pest management (IPM) by using selective insecticides along with a safe re-introduction technique of the natural enemy after the chemical insecticide treatment. First, chemical insecticides were screened to select the high toxic commercial products against F. occidentalis. Five insecticides containing active components (pyriproxyfen+spinetoram, abamectin, spinosad, acetamiprid, and chlorpyrifos) were selected among 17 commercial products. These five selected insecticides gave different toxic properties to the natural enemy, O. laevigatus. Especially, abamectin and spinetoram gave relatively low toxicity to the natural enemy compared to organophosphate or neonicotinoid. Furthermore, the five selected insecticides were assessed in their residual toxicities against O. laevigatus. Organophosphate and neonicotinoid insecticides showed relatively longer residual toxicity compared to abamectin and spinosads. Indeed, abamectin or spinetoram did not give any significant toxicity to O. laevigatus after 3 days post-treatment. These residual effects were further supported by the assessment of the chemical residue analysis of the insecticides using LC-MS/MS. These results suggest an IPM technology: (1) chemical treatment of abamectin or spinetoram against sporadic outbreaks of F. occidentalis infesting hot pepper and (2) re-introduction of O. laevigatus to the crops after 3 days post-treatment to depress the equilibrium density below an economic injury level.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.4
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• pp.449-454
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• 1996

Cytogenetic effects of malathion and parathion, the organophosphorus pesticides were studied on goat lymphocytes in culture. The mitotic indices (% of blast cells + cells at metaphase) of goat lymphocytes showed corresponding decrease with the increase in dose of pesticides. Malathion had significant effect only at $150{\mu}g/ml$ or higher dosages while, parathion caused antimitotic effects even at the lowest dose ($5{\mu}g/ml$) tested. The clastogenic effects of malathion were significant ($p{\leq}0.05$) at $100{\mu}g/ml$. In higher doses, the effects were highly significant ($p{\leq}0.01$). The frequency of metaphase plates with chromosomal abnormalities were highest (22.0%) at $200{\mu}g/ml$. The incidences of chromosomal abnormalities were significant ($p{\leq}0.05$) in parathion treated series even at $5{\mu}g/ml$ dose level. At $10{\mu}g/ml$ or higher dose levels the difference between treatment groups and controls were more pronounced ($p{\leq}0.01$). Various types of chromosomal abnormalities were encountered in goat lymphocytes treated by malathion and parathion. However, the incidence of gaps, breaks, acentric fragments, dicentric chromosomes were higher than other types of structural and numerical abnormalities.

• Korean Journal of Veterinary Research
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• v.58 no.3
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• pp.167-170
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• 2018

Two 12-month-old cattle with anthelmintics containing trichlorfon the day before death presented to the Animal and Plant Quarantine Agency for diagnosis. In necropsy, they revealed enlargement of the spleens, redness of mucosa and serosa in stomachs and intestines, and friable kidneys. Histopathologically, hemorrhages in the spleens, omasums, abomasums, and intestines as well as renal tubular necrosis were observed. Trichlorfon was detected at above the lethal dose in the ruminal contents. Based on these findings, we diagnosed this case as death caused by trichlorfon poisoning.

• Journal of The Korean Society of Clinical Toxicology
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• v.5 no.1
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• pp.74-78
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• 2007

The carbamates are a group of insecticides derived from carbamic acid, with a broad spectrum of uses as agricultural and household garden insecticides. Carbamate insecticides are reversible cholinesterase inhibitors. Their inhibitory action is mediated by reversible carbamylation of acetylcholine, as with the organophosphate insecticides. Carbamates are absorbed by the body through multiple routes, including inhalation, ingestion, and dermal absorption. Although poisoning can result from occupational exposure or accidental ingestion, in most cases there is suicidal intent. This is particularly true in developing countries, where the highest incidence of morbidity and mortality from this cause occurs. Cardiac complications often accompany poisoning by carbamate compounds, which may be serious and often fatal. The extent, frequency, and pathogenesis of cardiac toxicity from carbamate compounds has not been clearly defined. Possible mechanismsinclude sympathetic and parasymphatetic overactivity, hypoxemia, acidosis, electrolyte derangements, and a direct toxic effect of the compounds on the myocardium. Patients with carbamate poisoning should immediately be transferred to an intensive or coronary care unit where appropriate monitoring and resuscitative facilities are available. We here report a case of acute coronary syndrome resulting from acute carbamate ingestionthat resulted in a healthy discharge.

• Korean Journal of Environmental Agriculture
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• v.28 no.4
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• pp.453-461
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• 2009

Killifish (Oryzias latipes) were exposed to an organophosphate pesticide, pirimiphos-methyl, in a flow-through system to determine the bioconcentration factor (BCF) following GLP (Good Laboratory Practice). This study was conducted at two different concentrations (1 and $10\;{\mu}$g/L) of $^{14}C$-labeled pirimiphos-methyl for 28 days uptake and 14 days depuration according to the OECD 305 test guideline. The $BCF_{ss}$ for total radioactive residues in whole fish were 1,251 and 1,277 for low and high concentrations, respectively. The $BCF_k$ based on the uptake and depuration rate constants were 1,200 for both low and high concentrations. During the depuration phase, the accumulated test substance was rapidly depurated from fish. Greater than 95% of the residue at steady-state was depurated after 2 days. Although the measured BCF values were high, pirimiphos-methyl could be evaluated as a low risk from bioaccumulation by aquatic organisms due to the short depuration period and low amount of bound residue (1.5%). We suggest that in evaluating bioaccumulation, not only the BCF should be considered, but also depuration time and bound residue in aquatic organisms give an indication of the potential environmental risks.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1760-1772
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• 2006

Mature acetylcholinesterase (AChE) gene (gm, 1,836 bp) was cloned from the housefly and successfully expressed in the E. coli CodonPlus (DE3) RIL system (GM-E, 72 kDa) with a yield of 1,630 mU/g fresh cells. Using the gm, 10 kinds of mutants were constructed and expressed for enhancing sensitivity to insecticides. The sensitivity of these mutants to five kinds of organophosphate (OP) and three carbamate insecticides was investigated by measuring the apparent bimolecular inhibition constant ($k_i=k_2/K_d$). Surprisingly, the sensitivity of quadruple mutant IGFT was enhanced as much as 7-fold for acephate, 164-fold for demeton-S-methyl, 484-fold for dichlorvos, 523-fold for edifenphos, 30-fold for ethoprophos, 30-fold for benfuracarb, 404-fold for carbaryl, and 107-fold for furathiocarb, compared with that of GM-E, although the sensitivity of each single point mutant was slightly increased. These mutational studies indicated that (i) contradictory to Walsh et al. [39], the residue 327 is the important key residue for enhancing sensitivity as much as the residue 262, (ii) the residue 82 and additional residues of 234, 236, and 585 are also important, and (iii) sensitivity was cooperatively accelerated as the number of strategic mutations increased.