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Reproduction and Parasitization Capacity of an Insect Parasitic Mite, Pyemotes moseri Yu et Liang (Acarina: Pyemotidae) New to Korea (국내 미기록 곤충기생성 응애, Pyemotes moseri Yu et Liang (Acarina: Pyemotidae)의 생식 및 기생 능력)

  • Kim, Se-Jin;Lee, Jong Ho;Yang, Chang Yeol;Kang, Taek-Jun;Cho, Myoung Rae;Hong, Ki-Jeong
    • Korean journal of applied entomology
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    • v.54 no.4
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    • pp.393-400
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    • 2015
  • An insect parasitic mite was found on a larva from Japanese apricot seed. The mite was identified as Pyemotes moseri Yu et Liang (Acarina: Pyemotidae) new to Korea. The host larva was identified as Eurytoma maslovskii using mitochondrial DNA sequencing analysis. We conducted preliminary study on its reproduction and parasitization capacity in laboratory condition. A mated female mite reared on Eurytoma maslovskii larva. We counted and sexed newborn progenies and then eliminated them during periodical observations. To test parasitization capacity, a PCR tube containing mass reared P. moseri and Japanese apricot seeds (assumed bear larva of E. maslovskii) placed in a stainless bath filled with potting soil. One month later, we surveyed the seeds whether the E. maslovskii larva parasitized by mite or not. We repeated this experiment three times with five replications each. Average life span (days from parasitization to the end of reproduction) of gravid females was 24.4 days (n=8). A gravid female reproduced 104.0 female progenies (n=8). Although there were more than seven Japanese apricot seeds per bath containing larva or pupa, we found parasitization only in two seeds.

Effect of Temperature on the Development of Copris tripartitus Waterhouse (Coleoptera: Scarabaeidae) (애기뿔소똥구리(Copris tripartitus Waterhouse)의 발육에 미치는 온도의 영향)

  • Bang, Hea-Son;Na, Young-Eun;Kim, Myung-Hyun;Roh, Kee-An;Lee, Jung-Taek
    • Korean journal of applied entomology
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    • v.46 no.3
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    • pp.357-362
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    • 2007
  • Copris tripartitus Waterhouse is a coprophagus insect which enhances the soil fertility as conveying dung into the soil. We compared preimaginal development, mortality, and size of C. tripartitus at various temperature condition (15, 17.5, 20, 25, 27.5, 30). Total preimaginal periods ranged from 118.0d at $17.5^{\circ}C$ to 49.3d at $27.5^{\circ}C$. Development threshold temperature (DT) and total effective temperature for the development of egg, larva, pupa and for complete development (egg to emergence) were 12.1, 11.2, 12.1 and $9.2^{\circ}C$ and 82.7, 462.0, 225.7 and 947.2 degree days, respectively. The mortality of egg and larva was the lowest at $25^{\circ}C$. The optimum temperature for hatchability and on the development of C. tripartitus was estimated to the $25^{\circ}C$.

Stability analysis of an existing utility tunnel due to the excavation of a divergence tunnel emerging from double-deck tunnel (복층터널의 분기터널 굴착에 따른 지하 공동구의 안정성 분석)

  • Nam, Kyoung-Min;Choi, Min-ki;Kim, Jung-Joo;Jafri, Turab H.;Yoo, Han-Kyu
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.2
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    • pp.231-248
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    • 2017
  • Government plans to construct a double-deck tunnel under a portion of Gyeongbu Expressway that will solve traffic problems and could also be used as a flood storage facility. Divergence tunnels connect the main tunnel to the urban areas and their construction effects on adjacent structures at shallow depth need to be analyzed. This study primarily includes the numerical analysis of construction effects of divergence tunnels on utility tunnels. The utility tunnel was analyzed for three cases of volume loss applied to the divergence tunnel and two cases of the angle between main tunnel and divergence tunnel ($36^{\circ}$ and $45^{\circ}$). The results show that the more the volume loss was applied and the shorter the distance was between utility tunnel and divergence tunnel, the more the utility tunnel was affected in terms of induced displacements, angular displacement and stability. The worst scenario was found out to be the one where the angle between main tunnel and divergence tunnel was $36^{\circ}$ and the distance between divergence tunnel and utility tunnel was 10 m, resulting in the largest displacement and differential settlement at the bottom of the utility tunnel. A relationship between the angular displacement and the distance to diameter ratio was also established.

Petrology and Geochemistry of Peridotite Xenoliths from Miocene Alkaline Basalt Near the Mt. Baekdu Area (백두산 지역의 마이오세 알칼리 현무암에 포획된 페리도타이트의 암석학적/지화학적 특성)

  • Kim, Eunju;Park, Geunyeong;Kim, Sunwoong;Kil, Youngwoo;Yang, Kyounghee
    • The Journal of the Petrological Society of Korea
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    • v.26 no.4
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    • pp.311-325
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    • 2017
  • Peridotite xenoliths in middle Miocene alkaline basalt from the Mt. Baekdu area are mainly anhydrous spinel lherzolites, displaying coarse-grained protogranular texture. These xenoliths have late-stage secondary orthopyroxene replacing olivine as the metasomatic mineral and glass formed along the grain boundaries. The studied xenoliths are characterized by the high $Mg{\sharp}[=100{\times}Mg/(Mg+Fe_{total})$ atomic ratio] of olivine, orthopyroxene and clinopyroxene (89~92) and the $Cr{\sharp}[=100{\times}Cr/(Cr+Al)$ atomic ratio] of spinel (10~29). Based on major-element data, the studied xenoliths are similar to those from the abyssal peridotites. Clinopyroxenes of the xenoliths are mostly enriched in incompatible trace elements, exhibiting two types of REE patterns: (1) LREE-depleted with $(La/Yb)_N$ of 0.1~0.2 and $(La/Ce)_N$ of 0.4~0.8. (2) LREE enriched with $(La/Yb)_N$ of 2.2~3.8 and $(La/Ce)_N$ of 1.2~1.6. The calculated equilibrium temperatures and oxygen fugacities resulted in $920{\sim}1050^{\circ}C$ and ${\Delta}fO_2(QFM)=-0.8{\sim}0.2$, respectively. It is suggested that the Mt. Baekdu peridotite xenoliths represent residues left after variable degrees of melt extraction(less than 15 vol%), which was subsequently subjected to different degrees of modal/cryptic metasomatism by silica- and LREE-enriched fluids (or melts).

Seasonal Occurrence and Ovarian Development of Bean Bug, Riptortus clavatus (톱다리개미허리노린재의 발생소장과 난소발육)

  • Huh, Hye-Soon;Huh, Wan;Bae, Soon-Do;Park, Chung-Gyoo
    • 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.

Transmission of Paulownia witches'-broom virus by tobacco leaf bug, Cyrtopeltis tenuis REUTER (담배장님노린재 (Cyrtopeltis tenuis REUTER)에 의한 오동나무천구 소병(도깨비집병) 바이러스의 매개전염)

  • La Y. J.;Pyun B. H.;Shim K. J.
    • Korean journal of applied entomology
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    • v.5_6
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    • pp.1-7
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    • 1968
  • The present investigation was initiated to find out the possible insect vector of the paulownia witches'-broom virus disease. 1. Among a number of piercing-sucking mouth type insects that were feeding on the witches'-broom infected Paulownia leaves, the tobacco leaf bug, Cyrtopeltis tenuis REUTER, was most abundant. Eggs, nymphs and adults of Cyrtopeltis tenuis were observed from the mid-August through the end of October. 2. It was found that Paulownia witches'-broom virus is transmitted by Cyrotopeltis tenuis. 3. On young Pnulownia plants, first symptom appeared twenty days after exposure to virus-bearing colonies of Cyrtopeltis tenuis. Forty days after exposure to these viruliferous insects, the characteristic symptom of Paulownia witches'-broom was apparent. 4. Paulownia witches' -broom virus was also transmitted by Cyrtopeltis tenuis to calendula and morning glory. No app"rent symptom was observed from tomato, carrot. aster, zinnia, cosmos, soybean and plantago at least until sixty days after exposure to the viruliferous colonies of Cyrtopeltis tenuis. 5. Calendula and morning glory appear to be highly suitable test plants for Paulownia witches'-broom vims because of their relatively short incubation period and distinct symptom appearance.

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Nematicidal Efficacy of Herbal Extracts against Meloidogyne hapla (당근뿌리혹선충에 대한 식물추출물의 살선충 효과)

  • Lee, Jung-Su;Choo, Ho-Yul;Lee, Dong-Woon
    • Korean journal of applied entomology
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    • v.50 no.4
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    • pp.315-324
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    • 2011
  • The nematicidal and egg haching inhibitory effects of extracts from 30 herbal plants (total 32 samples) against Meloidogyne hapla J2 juveniles and eggs was tested using the dipping method. At 1,000 ppm, extracts of Daphne genkwa flower buds, Eugenia caryophyllata flowers, Quisqualis indica fruits, and Zingiber officinale rhizomes produced > 80% mortality in J2 juveniles. At 125 ppm, extracts of D. genkwa and Q. indica produced 91 and 99% mortality, respectively. The toxicity of 5 selected plant extracts to M. hapla differed depending on the solvent used (i.e. hexane, methanol, hot water, or cold water). Hot water extracts of Z. officinale and Q. indica produced nematicidal efficacies of 99 and 99%, compared to 36 and 98%, respectively, with cold water extraction. Q. indica extract was highly active against M. hapla regardless of extraction method. The inhibitory effects of Areca catechu, D. genkwa, Desmodium caudatum, Pharbitis nil, Q. indica, and Z. officinale extracts on egg hatching of M. hapla was evaluated. At 1,000 ppm, D. genkwa, P. nil, and Q. indica extracts significantly reduced hatching at 7, 14 and 21 days after treatment. Numbers of juveniles in soil treated with the methanol extract D. genkwa (1,000 ppm) were significantly lower than in untreated soil in trials in pots and in a ginseng (Phanax ginseng) field. These results indicate that Q. indica extracts could be used as an environmental friendly control agent of M. hapla.

Effects of Schizonepeta Spica water extrect on the OVA-induced BALB/c mice model of allergic rhinitis (난알부민으로 알레르기 비염이 유발된 마우스에서 형개의 개선효과)

  • Song, Dea-Uk;Heo, Jun;Lee, SungYub;Kim, Jae-Hyun;Lee, Bina;Min, Ju-Hee;Kim, Eun-Young;Sohn, Youngjoo;Jung, Hyuk-Sang
    • The Korea Journal of Herbology
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    • v.30 no.6
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    • pp.39-46
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    • 2015
  • Objectives : The aim of this study was to evaluate the effect of Schizonepeta Spica water extract (SS) on the OVA-induced BLAB/c mice allergic rhinitis model.Methods : Thirty two BALB/c mice were equally assigned to 4 groups; the sham group, the control group, the cetirizine hydrochloride (Cet) treatment group, and the SS treatment group. Sham group was sensitized and challenged with saline, and the other groups were sensitized and challenged with OVA. The dosage of SS was 7.6 mg /kg·day, and Cet was 10 mg/kg·day. Nasal rubbing and sneezing were measured by the behavior observation. The concentrations of IL-1β, IL-10, TNF-α and MIP-2 in the sera of allergic rhinitis model were measured by mouse cytokine/chemokine magnetic bead panel kits. Total IgE and OVA-specific IgE were measured by ELISA method. Epithelial thickness and eosinophil infiltration of nasal septum was investigated by histological examination.Results : The clinical symptoms that increased in control group were significantly reduced in SS-treated group. Serum total IgE and OVA-specific IgE in the SS-treated group were significantly reduced compared to the control group. The concentration of IL-1β, IL-10, TNF-α and MIP-2 in SS-treated group showed a significant reduction compared to the control group. The infiltration of eosinophil into nasal tissues of SS-treated group decreased markedly compared to control group, and thickness of nasal septum in nasal mucosa showed a significant reduction compared to control group.Conclusions : According to the above result, it is suggested that SS may inhibit the early and late phase of allergic rhinitis reaction.

A Study on Magnetic Cure System Depending on Dominant Direction of Meridian using Yangdorak Diagnosis Machine with 24 Channels (24채널의 양도락진단기를 이용한 경락의 우세방향에 따른 자기치료시스템에 관한 연구)

  • Kim, Byoung-Hwa;Lee, Woo-Cheol;Han, Gueon-Sang;Sagong, Seok-Jin;Ahn, Hyun-Sik;Kim, Do-Hyun
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.39 no.2
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    • pp.34-43
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    • 2002
  • In this paper, with the reference of the pulse wave acquired by the pulse-checking device, it is measured the impedance on the key measuring points of the 12 kyungmaks of the human body's left and right by using 24-channels Yangdorak machine. Then, based on the Fuzzy theory, this study diagnosed the each meridian's strength and weakness. After that, both the strengthening and weakening stimulus of magnetic fields are applied to the dominant direction to find out how the degree of strength and weakness of the meridian changed. Ultimately, the magnetic therapy that can stimulate the magnetic field at the time of diagnosis and thereby balancing the interactive of five-system(O-hang) have been materialized. For the stimulation of magnetic fields, a stimulating device which can change the direction and time on a specific part of the key measuring points of the limbs of 24 kyungmaks have been developed and used. The therapeutic methods are as follows. First, the strength and weakness of the meridian have been determined. Second, both the extremely weak meridian of Yin(Shade) and Yang(Shine), and the extremely strong meridian of Yin and Yang were adjusted by applying appropriate ascending and descending stimuli respectively. All these adjusting processes can now be carried out automatically on a personal computer(PC). 

Spawning Character and Early Life History of the Endangered Korean Dwarf Loach, Kichulchoia brevifasciata (Teleostei: Cobitidae) (멸종위기종 좀수수치 Kichulchoia brevifasciata의 산란기 특징 및 초기생활사)

  • Ko, Myeong-Hun;Bang, In-Chul
    • Korean Journal of Ichthyology
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    • v.26 no.2
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    • pp.89-98
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    • 2014
  • Eggs development and early life history of the endangered Korean dwarf loach, Kichulchoia brevifasciata (Teleostei: Cobitidae) was investigated to provide basic information regarding biological characteristics and restoration. Adult fish specimens were sampled using a spoon net at Geurnsan-myeon, Goheung-gun, Jeollanam-do, Korea from June to July 2011. Since, spawning characteristics were analyzed, and females were induced to spawn by injecting Ovaprim (0.5 mL/kg) and their eggs were artificially fertilized with sperms by the dry method in the laboratory. Total length of mature female were 46~76 mm with GSI $9.6{\pm}3.77%$, and total length of mature male was 42~52 mm with GSI $3.5{\pm}1.04%$. Sex ratio (♂/♀) was 0.10, and there were no secondary sexual characteristics. The number of mature eggs was averaged $60{\pm}28.7$ per female. The lemon yellow eggs were slightly adhesive $1.46{\pm}0.07mm$ in diameter. The embryo hatched approximately 66 h after fertilization at $25^{\circ}C$, and the hatched larvae were averaged $5.5{\pm}0.07mm$ in total length (TL). At 6 days after hatching, the larvae averaged $9.0{\pm}0.29mm$(TL) and their yolk sac was completely absorbed. At 17 days after hatching, they entered the juvenile stage and reached $12.6{\pm}0.24mm$ (TL). At 80 days after hatching, the band patterns and external form of the juveniles were similar to those of adults, and they averaged $33.0{\pm}2.19mm$(TL).