• Journal of Ginseng Research
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• v.44 no.5
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• pp.704-716
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• 2020

Background: Ginsenoside Rh2 (GRh2) is a characterized component in red ginseng widely used in Korea and China. GRh2 exhibits a wide range of pharmacological activities, such as anti-inflammatory, antioxidant, and anticancer properties. However, its effects on Toxoplasma gondii (T. gondii) infection have not been clarified yet. Methods: The effect of GRh2 against T. gondii was assessed under in vitro and in vivo experiments. The BV2 cells were infected with tachyzoites of T. gondii RH strain, and the effects of GRh2 were evaluated by MTT assay, morphological observations, immunofluorescence staining, a trypan blue exclusion assay, reverse transcription PCR, and Western blot analyses. The in vivo experiment was conducted with BALB/c mice inoculated with lethal amounts of tachyzoites with or without GRh2 treatment. Results and conclusion: The GRh2 treatment significantly inhibited the proliferation of T. gondii under in vitro and in vivo studies. Furthermore, GRh2 blocked the activation of microglia and specifically decreased the release of inflammatory mediators in response to T. gondii infection through TLR4/NF-κB signaling pathway. In mice, GRh2 conferred modest protection from a lethal dose of T. gondii. After the treatment, the proliferation of tachyzoites in the peritoneal cavity of infected mice markedly decreased. Moreover, GRh2 also significantly decreased the T. gondii burden in mouse brain tissues. These findings indicate that GRh2 exhibits an antieT. gondii effect and inhibits the microglial activation through TLR4/NF-κB signaling pathway, providing the basic pharmacological basis for the development of new drugs to treat toxoplasmic encephalitis.

• Journal of the Korean Magnetics Society
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• v.23 no.1
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• pp.1-6
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• 2013

Spin-orbit coupling (SOC) effect is known to be the physical origin for various exotic magnetic phenomena in the low-dimensional systems. Recently, SOC also draws lots of attention in the study on magnetically doped thermoelectric alloys to determine their properties as the thermoelectric application as well as the topological insulator via the exact electronic structures determination near the Fermi level. In this research, aiming to investigate the spin-orbit coupling effect on the structural properties such as the lattice constants and the bulk modulus of the most widely investigated thermoelectric host material, $Bi_2Te_3$, we carried out the first-principles electronic structure calculation using the all-electron FLAPW (full-potential linearized augmented plane-wave) method. Employing both the local density approximation (LDA) and the generalized gradient approximation (GGA), the structural optimization is achieved by varying the in-plane lattice constant fixing the perpendicular lattice constant and vice versa, to find that the SOC effect increases the equilibrium lattices slightly in both directions while it markedly reduces the bulk modulus value implying the strong orientational dependence, which are attributed to the material's intrinsic structural anisotropy.

• The Journal of the Petrological Society of Korea
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• v.18 no.3
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• pp.211-221
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• 2009

This study illustrates the relationship between the petrographic characteristics of micrographic granite and the topographic features around Ijin-ri. Light-brown to light- gray granite is composed of intergrown fine-grained quartz + orthoclase, displaying micrographic textures. Miarolitic cavities are abundant. Many micro-landforms including tor, tafoni, and gnamma occurred in the micrographic granite of the study area. Tafoni is dominant in the north and gnamma is dominant in south. From our study of the occurrence and textural properties, two alteration zones were clearly identified; one is an external zone (A) characterized by abundant of small sized miarolitic cavities and the other is an internal zone (B) having them less than zone A. The former is dominant in north, and the latter is dominant in south. Particular geomorphologic features such as fluting cores and raised rims are present in the Ijin-ri area. This suggests that development of miarolitic cavities played an important role in the formation of the various geomorphologic features. Consequently, the petrogenesis of the micrographic granite is related to geomorphologic features in the external zone typified by abundant tafoni such as the tiger rock, and the formation of a platform as micro-landforms is influenced by thetextural differences of host rock in the internal zone.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.199-205
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• 2005

Seasonal occurrence and ovarian development of the bean bug, Riptortus clavatus Thunberg (Heteroptera: Alydidae), were studied at a soybean field and an university campus in which host plants are less available for the bug in Gyeongnam province with aggregation pheromone traps in 2004. It was assumed that the bug passed three generations per year at the university campus. Adults of the 1st generation might occur from early July to early August and that of the 2nd one from mid August to late September. Adults of the 3rd generation occurred from early October to mid November, entered reproductive diapause without carrying eggs in the ovaries of females during winter, and resumed activity from late March of the next year. Full-grown eggs in the ovaries of the overwintered females were first observed at the 1st half of May. Two peaks of occurrence, from early August to mid September and from mid October to mid November, were shown at soybean field that was sowed on May 24. The two peaks almost corresponded to those of the 2nd and 3rd generations at the university campus, respectively.

• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.227-231
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• 1974

During the period from 1971 to 73 physiologic races of potato late blight pathogen, Phytophthora infestans, causing severe losses of seed potato production at Alpine area, Korea, were investigated. In 1971, 68 isolates of the pathogen from various potato varieties were identified by the use of differential host Plants, and found that there were 10 races; 0, 1, 2, 3, 1.3, 1.4, 3.4, 1.3.4, 2.3.4. The most Predominant races for the year were 0 and 3. In 1972, the same procedure was repeated with 62 isolates of the pathogen, and found 5 different races; 0, 1, 4, 1.3 and 1.3.4. The most predominant race for the year was race 0. In 1973, six races; 0, 3, 4, 1.3, 3.4 and 1.3.4 were found from 76 isolates of the year, and the race 0 and 4 apperared as the most Predominant races for the year. Total of 11 races; 0, 1, 3, 4, 1.3, 1.4, 3.4, 1.3.4, 2.3.4 and 1.2.3.4, were found during the period from 1971 to 73 at Alpine area, among which the most predominant races were race 0, 3, and 4. The investigation indicated that the anual incidence of these races largely depended on the climatic conditions of the year.

• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.209-216
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• 1974

Life history and control methods of Aphanostigma iakusuiense Kishida were studied during April to November, 1974, in the Naju pear orchard area, Cholla Namdo. The results are summarized as follows: 1. More than $60\%$ of wintering eggs were found at the height of 1.5 to 2.0m from the soil surface, with approximately $10\%$ at 0.5 to 1.5m and 1.5 to 2.5m respectively. 2. There was little difference in the size of egg masses and hatching ratio $(12.7-13.7\%)$ between the varieties of host trees, Mansamkil and Kooksoo. 3. Hatching was not observed until April 6, but hatches of $12.8\%$ on April 13 and $90.6\%$ on May 4 were found. 4. During the hatching season in early spring, 8 chemicals were applied to test effectiveness of control. C8514, Metasystox, Acar 338, and Parathion were more effective than either Sevin or Malix for control of this insect. 5. Highest populations of pear phylloxera ocurred from August 20 to September 20 at which time levels of eggs and larvae were simillar in abundance. 6. In tests for control of this insect after in paper bags, DDVP, Loxon, C8514, Sevin, and Binapacryl were more effective than either EPN or Otran. 7. Predacious mite, Protolaelape pygmaeus Miller, and several species of lady beetles (Coccinellidae) preying on this insect as natural enemies were collected. The predation ratio of mites varied according to region: that is 0.77 to $18.6\%$ in Bia Orchard; $7.88-48.7\%$ in Noan Orchard and almost none in Youngsanoo Orchard. 8. The varietal difference in fruit damage by this insect was in the order of Choseng Chuck, Kooksoo, followed by Sin Ko, Mansamkil, Keumchon Choo, and Changsimrang.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.257-265
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• 2011

To investigate host preferencse of Myzus persicae on 15 sweet pepper cultivars grown in Jeonnam Province, EPG (electrical penetration graph) and life table experiments were carried out in the laboratory. Phloem phase times were significantly longer on Ferrari, Jinju, Debla, and Rapido than Orobell and Thialf. Non-penetration times were conversely observed. Life span, reproduction period, total fecundity, and intrinsic rate of increase ($r_m$) of M. persicae, were higher on Ferrari, Debla, Orange glory, and Jinju than on Purple, GreenAce, Orobell, and Thialf. On the bases of these results, we conclude that M. persicae preferred Ferrari, Jinju, Orange glory, and Debla among the 15 tested sweet pepper varieties. However, we could not show the preference of the aphid for Purple, Orobell, and Thialf.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.479-484
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• 2012

The occurrence of plum fruit moth, Grapholita dimorpha, has been recently reported in apple orchards in Korea. It has been suspected that G. dimorpha and its related species, G. molesta, may occur simultaneously in other host plants. This study reports the occurrence of G. dimorpha in pear orchards of different localities in Korea. The identification of G. dimorpha was determined by morphological characters and the DNA marker. The cross-trapping of both species may be possible because the major sex pheromone (SP) compositions for the two species are similar. From the monitoring data, G. dimorpha and G. molesta were caught in SP lure traps of G. dimorpha and both species were also caught in SP lure traps of G. molesta. This cross-trapping of G. molesta to a SP lure of G. dimorpha varied significantly among pear orchards in different geographical localities. Furthermore, the occurrence peaks of the two species were not coincidental in all monitored orchards. These suggest that monitoring data obtained from each SP trap of both species in pear orchards may be mixed with two species, which would result in the over-estimation of population density and peak frequency on both species in pear orchards.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.343-348
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• 2012

Developmental period, mummification, pupal mortality, and sex ratio of Korean strain of Aphelinus varipes F$\ddot{o}$rster parasitizing the green peach aphid, Myzus persicae were studied at 20, 25, 30, and $35^{\circ}C$ in controlled climate cabinets. The plastic container with a leaf disc of sweet pepper (Capsicum annuum L.) was used as experimental units. Green peach aphids at different developmental stages were reared in four different temperatures and presented to A. varipes for 12 hours. A female adult of A. varipes was allowed to parasitize for 12 hours in each plastic petri dish. The periods from egg to adult of A. varipes were 18.3 days, 14.7 days, 10.4 days, and 9.3 days at $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$, respectively. The pupal mortalities of A. varipes were 0%, 1.5%, 2.8%, and 10.2% at $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$, respectively. The mummifications of A. varipes were significantly different in all developmental stages of the aphid. The mummification of A. varipes parasitizing green peach aphid was the highest at 1st and 2nd in $20^{\circ}C$ and $25^{\circ}C$, but the highest at 3rd (84.4-85.0%) in $30^{\circ}C$ and $35^{\circ}C$. The host feedings of A. varipes were $20^{\circ}C$ (12.5%), $25^{\circ}C$ (17.3%), $30^{\circ}C$ (16%), and $35^{\circ}C$ (10.9%), respectively. The sex ratios of A. varipes female were $20^{\circ}C$ (49%), $25^{\circ}C$ (46%), $30^{\circ}C$ (69%), and $35^{\circ}C$ (60%), respectively.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.38 no.3
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• pp.304-315
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• 2001

In this paper, we peformed the real-time implementation of AMR(Adaptive Multi-Rate) speech coding algorithm which is adopted for IMT-2000 service using TMS320C6201, i.e., a Texas Instrument´s fixed-point DSP. With the ANSI C source code released from ETSI, optimization is performed to make it run in real-time with memory as small as possible using the C compiler and assembly language. Implemented AMR speech codec has the size of 32.06 kWords program memory, 9.75 kWords data RAM memory, and 19.89 kWords data ROM memory. And, The time required for processing one frame of 20 ms length speech data is about 4.38 ms, and it is short enough for real-time operation. It is verified that the decoded result of the implemented speech codec on the DSP is identical with the PC simulation result using ANSI C code for test sequences. Also, actual sound input/output test using microphone and speaker demonstrates its proper real-time operation without distortions or delays.