• The Korean Journal of Zoology
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• v.37 no.1
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• pp.97-103
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• 1994

Catalase 억제제로 알려져 있는 AT가 Pn에 중독된 생쥐 생존율을 유의하게 감소시켰다. 생쥐의 간장 폐 및 신장에서 catalase 활성도가 현저히 감소되었으며, PQ와 AT 병합투여군에서 Catalase 활성은 PQ 단독투여 군에 비하여 유의한 감소를 나타냈으나 glutathione량과 SOD 활성은 PQ 단독투여군과 유의한 차이를 나타내지 않았다. 또한 광학현미경 검색상 PQ 단독투여 군에서 사구체와 요세관이 손상되었으나 AT의 병합투여군에서 사구체와 요세관의 손상이 더욱 증가됨을 보여주고 있다. 이상의 실험 결과로 PQ의 신독성이 AT 병합투여로 더욱 증가됨을 알 수 있는데 이러한 결과는 AT가 신장 Catalase를 억제하여 증가된 과산화수소에 의해 나타난 독성의 결과로 생각되며, 과산학수소는 Haber-Weiss 반응이나 trenton 반응 또는 paraquat radical과 직접 반응하여 hydroxvl radicals을 생성하므로 PQ 독성은 과산화수소의 생성과 관련이 있는 것으로 추정된다.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.4
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• pp.191-199
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• 2018

The harmonic reduction method of ac motor drive, ACL and DCL were commonly used, but the current distortion ratio was only 35%, thus the several different types of filters as BBHF(broad band harmonic filter), HHF(hybrid harmonic filter), NHHF(new hybrid harmonic filter) have been developed to satisfy the IEEE Std. 519 harmonic limitation. However, these filters had been limited marketability due to cost and size problems. This study suggests the methods to reduce cost and size of the harmonic filter including topologies, besides we discussed simulation results of the power system with regard to the implementation and performance of the filters.

• Journal of Environmental Science International
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• v.1 no.2
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• pp.81.1-86
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• 1992

The amounts of ascorbic acid in chloroplasts treated with light and light+paraquat (PQ) were reduced by 81 and 82% of initial level, respectively at 24 hr at incubation. And those treated with dark and dark+PQ were decreased by W and 55% of the original level, respectively. Malondialdehyde (MDA) contents at 24 hr of dark and dark+PQ treatment were increased by 6 and 31% of the initial level, respectively. When chloroplasts were treated with light and light+PQ, MDA contents after 24 hr were increased by 88 and 146% of the initial level, respectively. SOD activities treated with light and light+PQ were increased by 10 and 20% of the initial level, respectively for 3 hr and thereafter reduced by 46 and 49% of the original level, respectively at 24 hr. However, the SOD activities treated with dark and dark+PQ were decreased by 37 and 30% of the initial level, respectively. It is considered that PQ triggers the oxidation of ascorbic acid, the induction of lipid peroxidation and the inactivation of SOD under light so that PQ has inhibitors effect on the pathway of plant metabolism. Key word: ascorbic acid, malondialdehyde, superoxide dismutase, paraquat, lipid peroxidation.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.1 no.2
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• pp.81-86
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• 1997

The amounts of ascorbic acid in chloroplasts treated with light and light+paraquat (PQ) were reduced by 81 and $82\%$ of initial level, respectively at 24 hr at incubation. And those treated with dark and dark+PQ were decreased by 46 and $55\%$ of the original level, respectively. Malondialdehyde (MDA) contents at 24 hr of dark and dark+PQ treatment were increased by 6 and $31\%$ of the initial level, respectively. When chloroplasts were treated with light and light+PQ, MDA contents after 24 hr were increased by 88 and $146\%$ of the initial level, respectively. SOD activities treated with light and light+PQ were increased by 10 and $20\%$ of the initial level, respectively for 3 hr and thereafter reduced by 46 and $49\%$ of the original level, respectively at 24 hr. However, the SOD activities treated with dark and dark+PQ were decreased by 37 and $30\%$ of the initial level, respectively, It is considered that PQ triggers the oxidation of ascorbic acid, the induction of lipid peroxidation and the inactivation of SOD under light so that PQ has inhibitory effect on the pathway of plant metabolism.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.1
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• pp.85-90
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• 2022

This study presents a Real-Time Power Quality(:PQ) Evaluation methodology that reflects customer's load characteristics. Author determined PQ as [Ideal], [Measured], [Acceptable], and evaluated measured PQ between Ideal and Acceptable by using Ideal AHP. Author determined Load as Resistance, Electric Motor, and Electronics, and evaluated PQ reflect Load characteristics. As future studies, author has plan to study 1:1 matrix and overall PQ evaluation including year-based PQ.

• BMB Reports
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• v.37 no.5
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• pp.618-624
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• 2004

All members of R. glutinosa show the unique characteristic of intrinsic tolerance to paraquat (PQ). Antioxidant enzymes have been proposed to be the primary mechanism of PQ resistance in several plant species. Therefore, the antioxidant enzyme systems of R. glutinosa were evaluated by comparatively analyzing cellular antioxidant enzyme levels, and their responses of oxidative stresses and hormones. The levels of ascorbate peroxidase (APX), glutathione reductase (GR), non-specific peroxidase (POX), and superoxide dismutase (SOD) were 7.3-, 4.9-, 2.7- and 1.6-fold higher in PQ-tolerant R. glutinosa than in PQ-susceptible soybeans. However, the activity of catalase (CAT) was about 12-fold higher in the soybeans. The activities of antioxidant enzymes reduced after PQ treatment in the two species, with the exception of POX and SOD in R. glutinosa, which increased by about 40%. Interestingly, the activities of APX, SOD and POX in R. glutinosa, relative to those in soybeans, were further increased by 49, 67 and 93% after PQ treatment. The considerably higher intrinsic levels, and increases in the relative activities of antioxidant enzymes in R. glutinosa under oxidative stress support the possible role of these enzymes in the PQ tolerance of R. glutinosa. However, the relatively lower levels of SOD versus PQ tolerance, and the mixed responses of antioxidant enzymes to stresses and hormones, suggest a possible alternative mechanism(s) for PQ tolerance in R. glutinosa.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.1
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• pp.1-8
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• 2018

ACL and DCL are have been conventionally used for reducing harmonic current on the input side of an ACMD. The current distortion ratio ITHD using ACL and DCL is only 35% to 85%, therefore to satisfy the IEEE Std. 519 requirements, the line filters has been focused as an alternative means. Those are installed between the AC power supply and the input of the ACMD, and must meet the IEEE Std. 519, be economical and be compact. To contribute to the widespread of using these line filters, we discussed concerning its topologies, simulation results, prototype test results as well as the cost evaluations. It included not only the proposed (NHHF) new hybrid harmonic filters which have both merits of simplicity and economic but also the past (BBHF) broadband harmonic filters and (HHF) hybrid harmonic filters.

• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.214-220
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• 2004

Power quality monitoring is the cornerstone for power quality analysis, diagnosis and improvement. The measurement of power quality (PQ) evolves from instantaneous metering to continuous monitoring. Furthermore, recent technologies enable us to construct more flexible, reliable, rapid and economical power quality monitoring system (PQMS). Therefore, this paper presents an improved PQMS with a new distributed monitoring structure. The proposed PQMS consists of a PQ meter, PQ analyzer and GUI. The PQ meter only collects raw data and the PQ analyzer performs power quality analysis. It has several advantages compared to conventional structures in economic efficiency, modularity, speed, etc. PQ monitoring algorithms to catch steady-state trends and to detect PQ events are also adapted to the proposed structure. Using the proposed structure and monitoring algorithm, a prototype PQMS is constructed and real-time testing is performed.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.1
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• pp.35-39
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• 2016

To conduct a kinetic study of paraquat (PQ), we investigated 9 patients with acute PQ intoxication. All of them ingested more than 20 ml of undiluted PQ herbicide to commit suicide and arrived at our hospital early, not later than 7 h after PQ ingestion. The urine dithionite test for PQ in all of the nine patients was strongly positive at emergency room. Blood samples were obtained every 30 min for the first 2~3 h and then every 1 or 2 h, as long as the clinical progression was stable among the patients for 30 h after PQ ingestion. The area under the plasma concentration-time curve ($AUC_{inf}$), which was extrapolated to infinity, was calculated using the trapezoidal rule. Toxicokinetic parameters, such as the terminal elimination half-life, apparent oral clearance, and apparent volume of distribution ($V_d/F$) were calculated. The maximum PQ concentration ($C_{max}$) and the time to reach maximum PQ concentration ($T_{max}$) were also obtained. Plasma PQ concentrations in nine patients were well described by a bi-exponential curve with a mean terminal elimination half-life of $13.1{\pm}6.8h$. $C_{max}$ and $AUC_{inf}$ were $20.8{\pm}25.7mg/l$ and $172.5{\pm}160.3h{\cdot}mg/l$, respectively. Apparent volume of distribution and apparent oral clearance were $50.9{\pm}61.3l/kg$ and $173.4{\pm}111.2l/h$, respectively. There were a significant correlation (r=0.84; p<0.05) between the PQ amount ingested and $C_{max}$. $AUC_{inf}$ also showed a significant correlation (r=0.83; p<0.05) with the PQ amount ingested. These correlations provide evidence that PQ has dose-linear toxicokinetic characteristics.

• Journal of Life Science
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• v.18 no.1
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• pp.129-135
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• 2008

Paraquat (1,1-dimethyl 4,4' -dipyridium dichloride; PQ) is a kind of herbicide. Terminalia chebulae (TC) has been used as a medicine in China and in Korea for treating illnesses such as diarrhea, collapsed anus, spasmodic, diphtheria, asthma etc.. This study was to examin new physiological activities of methanol extract of TC (TCM) on the toxicity of PQ. It was observed biochemical effects on the toxicity of PQ in kidney and lung tissues after treatment orally administered 100, 200, 300 mg/kg of TCM daily for two weeks. In the experiment related to the toxicity of PQ, we got following results: renal and pulmonary lipid peroxide contents, activities of aminopyrine N-demethylase, aldehyde oxidase and xanthine oxidase were significantly increased in control group as compared with normal group, in the treatment of TCM the values were decreased as compared with control group. Activities of superoxide dismutase, catalase and glutathione peroxidase which are free radical scavenging enzymes were also increased in control group as compared with normal goup, but were decreased in TCM group as compared with control group. Collagen content and glucose-6-phosphatase activity in lung tissue were increased in control group as compared with normal, but was decreased in TCM group as compared with control group. From these results, we concluded that TCM can playa role as an effective agent to decrease toxicity of PQ.