• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.365-372
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• 2012

Native of soybean aphid (Aphis glycines Matsumura) is an Asia and aphid is one of the dangerous pests in soybean [Glycine max (L.) Merr.]. High density aphid populations can reduce crop production by causing severe damage. The objective of this study was evaluation of resistance to the soybean aphid in soybean cultivars and germplasms. A total of fifty five soybean cultivars or germplasms, including two susceptible and two resistant check varieties, were infested to evaluate their resistance in the field cage and greenhouse test by aphid colonies which derived from wild collected one soybean aphid biotype in Korea. The average number of reproduced soybean aphid was evaluated with 62.7 aphids in the resistant check variety PI 567598B and also estimated with 1,807 aphids for susceptible check variety Williams 82. In soybean varieties and germplasms, the average reproduced soybean aphid populations ranged from the lowest 497 aphids for Junjeori to the highest 3,862 aphids for Mansu. About seventy six percent of soybean cultivars and germplasms were shown high density soybean aphid populations when compared with another susceptible check variety PI 567543C in the field cage test. From the greenhouse test to evaluate aphid index, 87.3% of soybean cultivars or germplasms presented aphid index with 9.0. No soybean cultivars and germplasms were observed with soybean resistant phenotype when regarded a aphid resistant level as less than 10% aphid reproductions compared with susceptible check Williams 82. Although no Korean soybean cultivars were identified with resistant trait to the soybean aphid, we found one great resistant genetic resource PI 567598B in this study. This result will be helpful to further study for providing useful genetic information for soybean researchers.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.133-136
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• 2017

Fermentation plays a vital role in the nutritional enrichment of food. Korea has a long tradition of adding fermented food to the daily diet and jeotgal is one of the common fermented and salted foods in Korean cuisine. In our study, we added soymilk as an additive to squid jeotgal to improve its functionality. We mixed different concentrations of soymilk (2, 5, and 10 mg/g) with squid jeotgal samples, fermented them for one week, and then tested their antioxidant and anticancer activities to compare with those of squid jeotgal samples without soymilk additive. To investigate the anticancer characteristics, glutathione-S-transferase (GST)-pi enzyme assay was used. To test the antioxidant activities, various assays were performed, including 2,2-diphenyl-1-picryl hydrazyl free radical scavenging activity, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium saltradical cation scavenging assay, and reducing power assay. Samples fermented with a small amount of soymilk showed excellent anticancer activity. The addition of only 2 mg/g of soymilk to squid jeotgal inhibited the activity of GST-pi by almost 50% when compared with the sample with no addition. Moreover, no undesirable bitterness or astringency was noticed. Our results could help to improve the current food status of squid jeotgal and it could be used to reduce the risk of chronic disease along with its basic nutritional function.

• Journal of Periodontal and Implant Science
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• v.36 no.1
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• pp.211-221
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• 2006

The aim of present study was to evaluate the influence of periodontal status of adjacent tooth and loading time to the prevalence of red complex of implant sulcus. In 97 patients, partially edentulous subjects with endosseous root-form implants were selected. All subjects were medically healthy and had not taken systemic antibiotics and professional plaque control 3 months before sampling. The number was as follows: clinically healthy implants:161, clinically unhealthy implants:22, clinically healthy adjacent teeth:73, clinically unhealthy adjacent teeth:38. All teeth and implants of each patient were examined probing depth(PD), modified sulcus bleeding index(mSBI), and modified plaque index(mPI), and samples of subgingival plaque were obtained at each site with sterile curet or fine paper points, then the plaque transferred to PBS. Obtained samples were examined for the presence of P. gingivalis, T. forsythensis, and T. denticola by the polymerase chain reaction (PCR). The relationship among clinical parameters and the colonizations by the 3 bacterial species from adjacent teeth and implants region were analyzed by student t-test (p<0.05). The results of this study were as follows: 1. mPI and mSBI of implant increased with increasing of same indices of adjacent tooth(p=0.03,0.001), but not in the PD . 2. The mPI, mBI, PD of implants was higher when red complex exist. 3. The prevalence of red complex was higher when the periodontal condition is unhealthy. 4. The prevalence of red complex of implants has no significant relation to the probing depth of adjacent tooth. 5. Prevalence of P. gingivalis, T. forsythensis of implants increased with loading time. (p=0.02,0.018) These results shows the importance of oral hygiene and supportive periodontal therapy.

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.163-169
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• 1991

The photochemical and photophysical properties of N-(2-haloarylmethyl)pyridinium, N-(arylmethyl)-2-halopyridinium, N-(2-haloarylmethyl)-2-halopyridinium salts and N-(2-halobenzyl)-isoquinolinium salt are studied. The pyridinium salts photocyclize to afford isoindolium salts, while the isoquinolium salts do not. In the photocyclization of N-(2-chlorobenzyl)-2-chloropyridinium salts, pyrido[2,1-a]-4-chloroisoindolium salt is formed by the cleavage of chlorine of pyridinium ring. This indicates that the excited moiety is not the phenyl ring, but the pyridinium ring. The triplet states of the pyridinium salts are believed to be largely involved in the photocyclization, since oxygen retards most of the reaction. Some assistance of a ${\pi}$-complex between the excited chlorine moiety of the salt and phenyl plane of the same molecule is required to explain the reactivity of the salts. N-(Benzyl)-2-chloropyridinium salt is two times more reactive than N-(2-chlorobenzyl)pyridinium salt. N-(Benzyl)-2-chloropyridinium salt can form ${\pi}-complex$ effectively because of the electron-rich phenyl group. The ${\pi}$-complex affords an intermediate, phenyl radical by cleaving the chlorine atom. The photocyclized product, isoindolium salt is obtained by losing the hydrogen atom from the phenyl radical. The reactive pyridinium salts 1a, 2a and 3a have a low fluorescence quantum yield (${\Phi}F$ < 0.01) and a higher triplet energy (ET > 68 kcal/mole) than the unreactive quinolinium salt. The unreactivity of isoquinolinium salt can be understood in relation to its high fluorescence quantum yield and its low triplet energy $(E_T = 61 kcal/mole).$.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.3
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• pp.159-169
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• 2023

Purpose : Though other Citrus spp. have reported their anti-inflammatory and antioxidative activities in previous studies, the biological activity of Kiyomi (Citrus unshiu × C. sinensis) has not been reported yet. Therefore, this study attempted to analyze the anti-inflammatory mechanisms of Kiyomi leaf ethanol extract (KLEE) in lipopolysaccharide (LPS) stimulated RAW 264.7 cells. Methods : The cytotoxic effect of KLEE in RAW 264.7 cells was determined by WST-1 assay. Bacterial endotoxin, the concentration of nitric oxide (NO) was analyzed by the Griess reaction. In addition, Western blot analysis was applied to measure the protein expression level of inducible NO synthase (iNOS). The phosphorylated status of the critical inflammatory transcription factor, nuclear factor (NF)-𝜅B, and its upstream signaling molecules, phosphoinositide 3-kinase (PI3K)/Akt as well as mitogen-activated protein kinases (MAPKs), were also measured by Western blot analysis. Results : KLEE was not cytotoxic up to a concentration of 200 ㎍/㎖, and protein expression levels of iNOS and cyclooxygenase (COX)-2, enzymes that counteract NO and prostaglandin (PG) E2 production, were inhibited by KLEE treatment. The phosphorylated status of PI3K/Akt as well as MAPKs including extracellular regulated kinase (ERK), c-jun NH2kinase (JNK), and p38, were significantly attenuated by KLEE treatment in LPS stimulated RAW 264.7 cells. Moreover, one of phase II enzymes, heme oxygenase (HO)-1 which has known for its anti-inflammatory capacity, was strongly induced by KLEE treatment. Conclusion : Consequently, KLEE treatment significantly attenuated the production of NO as well as the expression levels of iNOS and COX-2 in LPS-stimulated RAW 264.7 cells. The inflammatory transcription factor, NF-𝜅B, as well as its upstream signaling molecules, PI3K/Akt and MAPKs, were also diminished by KLEE treatment with statistical significance in LPS-stimulated RAW 264.7 cells. These results suggest that KLEE might be a promising candidate for the attenuation of inflammatory disorders.

• Tuberculosis and Respiratory Diseases
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• v.42 no.6
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• pp.913-922
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• 1995

Background: When we define the pressure of pulmonary vasculature in which a recruitment of blood flow occurs as $P_I$ and the proportion of change in pulmonary artery to that in cardiac output as IR and then we compare PI and IR with pulmonary vascular resistance, we would find some problems in pulmonary vascular resistance. In other words, it is the theory that, IR should be increased mainly in pulmonary embolism in which decreases the cross sectional area of pulmonary vasculature. But there are many contradictory reports resulted from various researches and the fact is known widely that any difference exists between PVR and PI, IR. For this reason, the purpose of this study is to observe how PI and IR change at the time of the outbreak and during treatment of the pulmonary embolism, and to find out the meaning of these new indicators and the difference from the pulmonary vascular resistance used generally when we subdivide the pulmonary vascular resistance into PI and IR. Method: After making AV fistula in experimental dog, we controlled cardiac output at the intervals of 15 minute in case of three kinds(all AV fistula are obstructed, only one of fistula is open and all of fistula is open), and after evoking massive pulmonary embolism with radioactive autologous blood clots, we measured the mean pulmonary artery pressure, and calculated PI and IR. We observed the pattern of change in PI and IR, without giving the control group any specific treatment and with injecting intravenously rtPA in the Group 1 and Group 2 at the dose of 1mg per kg, for 15 minutes fot the former and 3 hours for the latter. Result: 1) Pulmonary vascular resistance showed a change similar to that of pulmonary artery pressure and in all three group, PVR increased significantly, but group 1 and group 2 showed tendency that PVR keeps on decreasing after treatment, and the rate of decrease in group 1 is more rapid than group 2 significantly. 2) Both intersection(PI) and degree(IR) are proved statistically significant, in view of the straight line relationship between cardiac output and pulmonary artery pressure, calculated by minimal regression method. 3) PI changed similarly to pulmonary vascular resistance, while in the IR which is theoretically more similar to PVR, there was no significant difference or change after rtPA infusion. Conclusion: In the pulmonary embolism, Both change in IR which means real resistance of pulmonary vasculature and PI which was developed due to secondary vasoconstriction by pulmonary embolism are reflected same time.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.9
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• pp.24-30
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• 2009

This paper is proposed by fuzzy-based MPPT control of photovoltaic to drive induction motor. Design and prototype implement of a fuzzy logic(FL) controller for maximum power extraction from a stand-alon photovoltaic. Error and the change of error between maximum power and real power are used by input of fuzzy controller. Moreover, it output changing of voltage from control constant. The validity of this paper is proved by comparing maximum power point tracking and performance of motor drive through comparison fuzzy and PI of tradition method.

• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.5
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• pp.417-425
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• 2006

This paper presents a new speed sensorless vector control scheme of Spindle Induction Motors(SIM) which can be successfully applied to at any speed including even zero speed. The proposed sensorless vector control of SIM uses rotor flux estimator with a variable bandwidth. This approach is based on the Closed-Loop Rotor Flux Observer(CLRFO) which includes a variable bandwidth of the PI controller. For low speed operation, the bandwidth of CLRFO has a variable bandwidth structure according to the estimated rotor velocity. The experimental results show the satisfactory operation of the proposed sensorless algorithm.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.462-465
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• 2001

The wound induction motor can provide high starting torque and reduced starting current simultaneously by inserting large scale resistor. And this technique is one of the well known methods among the induction motor starting methods and generally used for heavy load starting such as Crain and Cement factories. The conventional PI controller has been widely used in industrial application due to the simple control algorithm and in general, PI controller is used for control of current, torque, position, and speed for the wound induction motor drive system. However, the system may result in poor performance since sensors have to be used, which in turn is limited by the environmental condition. Recently, to overcome these problems, many sensorless vector control methods for the wound induction motor have been studied. This paper presents MRAS method with on-line stator resistance tuning for sensorless vector control of the wound induction motor drive. In conventional MRAS method, in low frequency, stator resistance variation can result in poor performance. Therefore, to overcome several shortages of the conventional MRAS caused by parameter variation and enhance robustness of the sensor less vector control, this paper investigates a MRAS method with on-line stator resistance tuning for sensorless vector control of the wound induction motor. The validity and effectiveness of the proposed method is verified through digital simulation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.3
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• pp.45-53
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• 2015

A I-V and P-V characteristic of solar cell is changed to nonlinear by radiation and temperature. Therefore, to use efficiently PV system, operating point of PV system is must operate at maximum power point always. A performance of conventional the PO and the IC method is depend on the step size. So it has weakness which is must select optimal step size. Also, MPPT control applying PI and fuzzy control is not expected satisfactory performance, because of PI controller has fixed gain and fuzzy control has cumulative error by an integral calculus. Therefore, this paper proposes the VS-PO(Variable Stepsize - Perturbation & Observation) MPPT control that is automatically adjusted the step size according to the operating conditions. The VS-PO MPPT method proposed in this paper analyzes control characteristic about condition of radiation and compares with conventional methods. The validity of this paper proves using this results.