• Title/Summary/Keyword: 기생율

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Demonstration of the second intermediate hosts of Clinostomum complanatum in Korea (새인두흡충 제2중간숙주의 발견)

  • Jeong, Dong-Il;Gong, Hyeon-Hui;Mun, Ju-Hwan
    • Parasites, Hosts and Diseases
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    • v.33 no.4
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    • pp.305-312
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    • 1995
  • A species of metacercariae recovered from the fresh-water fish, collected from Kaumji (Pond), Kaechonji (Pond) and Ssanggyechon (River), Uisong-gun, Kyongsangbuk-do, Korea, was identified as Clinostomum compzcnatum by morphological observation and experimental infection to chicks. The excysted metacercariae, tongue-shaped and progenetic, were 3.28-4.27 mm in length and 0.94-1.46 mm in width. The adult flukes recovered from the chicks four days after infection were 4.20-4.86 mm long and 1.14-1.49 mm wide. Twelve species of the fresh-water fish were found to be infected with the metacercariae. The infection rate ranged from 1.6% (Zacco temminkii) to 88.9% (Acheilognathus rhombec and Microphwsogobio voluensis) . The intensity was highest in Cnrqssius curatus (13.0/fish infected) and the abundance (relative densityl was highest in A. rhombea (7.8/fish examined). This survey demonstrated for the first time the source of human infection by C. complnnntum in Korea.

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Biology of the hyperparasite Tetrastichus sp. (Hymenoptera : Eulopidae) (고차기생봉(高次寄生蜂) Tetrastichus sp.의 생태(生態))

  • Kim, Jong-Kuk
    • Journal of Forest and Environmental Science
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    • v.10 no.1
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    • pp.32-37
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    • 1994
  • This study was carried out to clarify the primary hosts of Tetrastichus sp. and its host relationship, development and reproductive capacity. Protopulvinaria mangiferae was parasitized by Aneristus ceroplastae, Microterys flavus, Coccophagus hawaiiensis. All of these primary parasitoid were attecked by the hyperparasite Tetrastichus sp.. Tetrastichus sp. was bound to be a solitary ectoparasite. Eggs were laid on the pupa of the primary host or attached to the inner surface of the integument of the scale insect. Threshold of the development and thermal constants for completion of immature stages were $9.8^{\circ}C$ and 272 day-degrees, respectively. At $25^{\circ}C$ the life span of both sexes without any food or with water were very short as compared with that with honey. After a pre-oviposition periods of about one day they laid on overage 220 eggs each, almost all during the first half of their life. The value of the net reproduction(Ro), the mean length of a generation(T) and the intrinsic rate of natural increase(r) were calculated as 99.6, 32days and 0.142 per female per day respectively.

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Resistance to Northern Root-knot Nematode, Meloidogyne hapla, in Peony Strains (당근뿌리혹선충에 대한 작약계통의 저항성 검정)

  • 박소득;김재철
    • The Korean Journal of Soil Zoology
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    • v.6 no.1_2
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    • pp.33-36
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    • 2001
  • This study was carried out to screen 11 peony varieties collected for resistance to northern root-knot nematode, Meloidogyne hapla. The larval population of Meloidogyne halpa to the Uisongjakyak, Taebaekjakyak, Doseo, EP368, EP512 peony were detected high denisties with individuals of 98-173 per 300 ml soil, but Sabeol, Yongsu, Kimchon, Pl23 peony showed low number of larvar with 21-60. The root rot were lowered in Yongsu, Kimchon peony than Uisongjakyak, Taebaekjakyak, EP368, EP512. It seems to involved with densities of 2nd juvernile population in that rot rate of root was increased as increase of 2nd stage larvae. Two peony, Uisongjakyak, Taebaekjakyak were susceptable to M. hapla with high egg mass formation which showed 49,28 in each root. And Yongsu, Doseo, EP368, EP512 were Mid resistance with 1-15 egg mass of each root. Whereas Sabeol, Kimchon, Pl23, EP337, EP425 were found to be resistant to M, hapla with few egg mass formation of 4-7 each root.

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A Study on Lactobacilli associated with Fungus Infection in Vaginosis (진균(Fungus)에 감염된 질증 환자에서 젖산균에 관한 연구)

  • Park, mi-soon;Chang, byung-soo
    • Proceedings of the Korea Contents Association Conference
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    • 2015.05a
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    • pp.171-172
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    • 2015
  • 질염 환자의 질분비물 도말에서 광학현미경상에서 고배율로 관찰한 결과 정상 상피세포에서는 질내 정상 pH를 유지하기 위해 무수한 젖산균의 존재를 확인할수 있었다. 그러나 저배율, 고배율의 광학현미경상에서 진균에 감염된 세포 주변에서 젖산균(lactobacilli)은 관찰되지 않았다. 주사전자 현미경 상에서 Candida albicans는 기능을 탈락한 상피세포의 세포질에 기생하며, biofilm의 성장환경을 만들며, budding을 통해 2차 딸세포를 형성하며, 성장과 증식을 끊임없이 반복함을 확인하였다. 성장과 재생이 주기적으로 일어나지 않은 면역력이 약화된 임산부나, 호르몬의 부족으로 인한 위축성 질염 환자는 상피세포층이 떨어지면서 나오는 글리코겐을 이용해 질내에 존재하는 lactobacilli균이 젖산을 풍부하게 만들 수 없으므로 감염증 발생이 더 높아진 것으로 사료된다.

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Design of Multiple Filter-Banks for Analog Cochlear Chip (아날로그 달팽이관 칩을 위한 다중필터의 설계)

  • Lee, K.;Woo, Y.J.;Kim, J.H.;Cho, G.H.
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.3142-3144
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    • 2000
  • 청각시스템의 저전력 및 가격의 저렴화를 위해 달팽이관의 BM(Basilar Membrain)모델을 아날로그 VLSI 마이크로 파워 공정으로 구현하고 있다. Lyon and Mead는 실리론 공정으로 달팽이관 모델을 효과적으로 구현하였다. 이는 단순 직렬 연결된 구조로 각 채널의 지연시간의 차이로 인해 인식율이 떨어질 수 있다. 본 논문에서는 소리의 주파수 정보 추출기능을 하는 직렬 연결된 트리구조(TSBF:Tree-structured Cascaded Bandpass Filter)의 16채널의 아날로그 중간대역통과 필터회로를 CMOS VLSI 공정을 이용하여 설계하였다. 직렬 연결된 저대역통과필터와 고대역통과필터로 각 채널의 중간대역통과 필터를 구현하였다. 이러한 구조에서는 각 채널의 지연시간이 동일하므로 인식율을 높일 수 있다. 그리고 고대역통과필터를 1-poly 디지털 공정으로 구현 가능하고 기생 캐패시터의 영향을 적게 받는 구조로 설계하였다.

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A Marking Technique for Exorista bombycis(Louis) (Diptera:Tachinidae) by Adding Dye to the Adult Diet

  • Swamy, K.C.Narayana;Devaiah, M.C.;Govindan, R.
    • Journal of Sericultural and Entomological Science
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    • v.35 no.1
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    • pp.73-76
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    • 1993
  • Adding a non-fluorescent dye, Rhodamine-B, to the adult diet of uzi fly, Exorista bombysis (Louis) has shown to be a useful method for marking the eggs for flight range experiments. The method is timesaving and the dye is safe to handle and the marked eggs are easy to detect. Files fed on the diet added with dye did not have much negative effect on adult mortality and fecundity, but egg hatchability was affected.

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Infection and Rapid Detection of Perkinsus sp. In Cultured Babyneck Clam, Ruditapes philippinarum from Western Coast of Korea (서해안 양식 바지락에 발생한 Perkinsus sp. 감염증과 신속검출)

  • Choi, Dong-Lim;Kwon, Jung-No;Park, Sung-Woo
    • Journal of fish pathology
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    • v.11 no.1
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    • pp.69-76
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    • 1998
  • An apicomplexan parasite, Perkinsus sp. was observed from the cultured baby clams, Ruditapes philippinarum, collected from the coast of Kochang and Taean (South Korea), where it caused seasonal mortality of clams. Several milky-white cysts were observed on the surface of gill and visceral mass of parasitised clams. The trophozoites of parasite had eccentric nucleus and proliferated by schizogony in gill, mantle, hepatopancrease and reproductive tissues, resulting in the formation of granuloma and the intensive infiltration of hemocytes in the tissues. During incubation in FTM, trophozoites increased in size, resulting in prezoosporangia which appeared as round black spheres when colored with Lugols iodine solution. The prevalence of Perkinsus sp. in clams was Kochang, 73.1%; Taean, 94.8% (during 9-mo. survey) and showed size-dependent infection. Hemacolor kit was useful to reduce time for diagnosis of the trophozoite of Perkinsus sp. that has been responsible of massive motalities in the clam.

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Development of Green Rice Leafhopper, Nephotettix cincticeps Uhler, Population in the Fields at Jinju (진주지방(晉州地方)에 있어서 끝동매미충 개체군(個體群)의 연중발생경과(年中發生經過))

  • UHM, KI-BAIK;LEE, MOO-HONG;Choi, Kui-Moon;PARK, JOONG-SOO
    • Korean journal of applied entomology
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    • v.24 no.4 s.65
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    • pp.203-208
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    • 1986
  • This study was carried out to investigate the seasonal occurrence of Green Rice Leafhopper(GLH), Nephotettix cincticeps Uhler population in the field at Jinju in $1977{\sim}1978$. GLH density was observed by suction catcher (D-Vac, 33cm in diameter) for overwintering population and by direct visual counting for paddy field population. GLH overwintered mainly as 4th-instar nymph in the levee and moved to the foxtail growing in the paddy with development after winter. The mean emergence date of adults, of the overwintered generation was on April 8 in 1977 and March 30 in 1978, and that of 1st generation was on June 11 in 1977 and June 10 in 1978. Adults of overwintered generation oviposited in foxtail from late April to early May. GLH occurred two generations in the paddy field and the population size in the paddy field was not greatly changed in two years.

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Report on Two Egg Parasitoid Species of Riptortus clavatus (Thunberg) (Heteroptera: Alydidae) on Soybean (톱다리개미허리노린재의 난기생봉 2종에 관한 보고)

  • Paik, Chae-Hoon;Lee, Geon-Hwi;Choi, Man-Young;Seo, Hong-Yul;Kim, Doo-Ho;La, Seung-Yong;Park, Chung-Gyoo
    • Korean journal of applied entomology
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    • v.46 no.2
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    • pp.281-286
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    • 2007
  • Two hymenopteran egg parasitoid species, Gryon japonicum (Ashmead) (Scelionidae) and Ooencyrtus nezarae Ishii (Encyrtidae), were emerged from eggs of bean bug, Riptortus clavatus Thunberg (Heteroptera: Alydidae). The former parasitoid is first recorded in Korea. Brief morphological and biological characteristics, and parasitism on R. clavatus eggs are described.

Suppression of the High Frequency Distortion by Adjustment of Transconductance of the Diode-Connected Transistor in the Current Mode Max Circuit for Multiple Inputs (다수 입력용 전류모드 Max 회로에서 다이오드결선 트랜지스터의 트랜스컨덕턴스 조정에 의한 고주파 왜곡 억제)

  • 이준수;손홍락;김형석
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.40 no.11
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    • pp.37-44
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    • 2003
  • A distortion suppression technology for employing multiple inputs in 3n+1 type current mode Max circuit is proposed using the adjustment of transconductance. If the number of input blocks of the current mode Max circuit increases, the high frequency distortion in the output signal grows. In this paper, it has been disclosed that the distortion in the multiple input Max circuit is proportional to such accumulated parasitic capacitance, to the derivative of the output signal and also to tile inverse of transconductance of the common diode-connected transistor. The proposed idea is by employing as larger transconductance of the common diode-connected transistor as possible. The effectiveness of the proposed idea has been proved through the HSPICE simulation for the current mode Max circuits with various numbers of input signals.