• Title/Summary/Keyword: 알기생

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닭에 대한 내부기생충의 피해

  • 김영환
    • KOREAN POULTRY JOURNAL
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    • v.3 no.6 s.20
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    • pp.41-45
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    • 1971
  • 누구나 다 아는 내부기생충(회충)$\cdots$$\cdots$ 그러나 그피해는 당신이 모르게 갑자기 나타난다. 왜?$\cdots$$\cdots$1달 자란 회충 한마리가 하루 5,000여개의 알을 낳기 때문이다. 정상을 벗어난 높은 폐사율, 성장부진, 산란이 피크에 올라가지 않을때, 난중이 빨리 증가하지 않을때 여러분은 그 닭의 기생충 보유유무를 체크할 필요가 있다.

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A Morphological Observation of an Egg Parasitoid, Anagrus incarnatus Haliday (Hymenoptera : Mymaridae), of the Rice Planthoppers (멸구류의 날기생봉 Anagrus incarnatus Haliday의 형태적 관찰)

  • 여윤수;장영덕;고현관
    • Korean journal of applied entomology
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    • v.29 no.1
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    • pp.1-5
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    • 1990
  • A morphological study on the immature and adult stages of Anagrus incarnatus Haliday was carried out under laboratory condition at 25$\pm$1$^{\circ}C$. The egg is sausage-shaped with a long slender pedicel. The first instar is a bag-shaped larva. The second instar larval form of A. incarnatus is similar to he "histriobdellid" stage. The antenna has 9 and 13 segments of the female and male, respectively. The first funicular segment of the female's antenna is very short, subspherical or globular type and the third funicular segment with one sensory ridge is longer than the forth. The forewing of A. incarnatus has 8-9 rows of discal hairs providing no bare space at the broadest part. The length of ovarian eggs, egg, 1st instar, and 2nd instar of A. incarnatus is 0.165, 0.215, 0.290, and 0.535 mm, respectively, and the width of each stages is 0.025, 0.057, 0.082, and 0.110 mm, respectively. The developmental periods for egg, 1st instar, 2nd instar, prepupa, and pupal stage are about 1, 1, 4, 1, 5-6 days, respectively.pectively.

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A Study on a Wideband Helical Antenna for Mobile Handset using Parasitic Element Effect (기생소자 효과를 이용한 이동 단말기용 광대역 헬리컬 안테나 연구)

  • 성원모;양묘근;전용승;이치우;박진희;최학근
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.14 no.9
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    • pp.899-903
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    • 2003
  • In this paper, a wide band helical antenna for mobile handset using parasitic element effect has been investigated. To obtain the effect of parasitic element, we utilized the cylindrical conductor which is not feed. As thickness of cylindrical conductor is increasing, second and third resonance frequency become abruptly variable. In case of that 4.5mm diameter parasitic element cylindrical conductor is inserted, normal mode helical antenna obtained bandwidth of around 900 MHz on the limit of R. L., - 5 dB.

Wideband Stacked Microstrip Antenna with Parasitic Patches for 800MHz Band (기생패치를 이용한 800MHz 대역 광대역 적층 마이크로스트립 안테나)

  • Kim, GunKyun;Lee, Jong-Ig;Ko, Jin-hyun;Rhee, Seung-Yeop
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.83-84
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    • 2016
  • A wideband stacked patch antenna with parasitic elements, rectangular and triangle shaped patches, is proposed. Two different shaped parasitic elements are placed in the above of main rectangular microstrip patch antenna in order to achieve wide bandwidth for 860 MHz band. Coupling between the main patch and parasitic patches is realized by thick air gap. The gap and locations of parasitic patches are found to be the main factor of the wideband impedance matching. The proposed antenna is designed on a ground plane with small size of $119mm{\times}109mm$ for application of compact transceivers. And the impedance bandwidth of the antenna should satisfied CDMA band to the 780MHz~890MHz.

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어린이 엉덩이가 가려울때 요충 조심

  • Chae, Jong-Il
    • 건강소식
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    • v.10 no.8 s.93
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    • pp.26-29
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    • 1986
  • 요충은 주로 어린이들을 많이 괴롭히는 기생충으로 항문을 가렵게 해서 긁을 때 어린이가 손으로 항문을 긁을 때 자신의 알을 묻히게 하여 다시 이 어린이의 입을 통해 재차 침입하게 된다.

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Molecular Identification of Trichogramma (Hymenoptera: Trichogrammatidae) Egg Parasitoids of the Asian Corn Borer Ostrinia furnacalis, Based on ITS2 rDNA Sequence Analysis (ITS2 rDNA 염기서열 분석을 통한 Trichogramma 속(벌목: 알벌과)의 조명나방 알기생벌에 대한 종 추정)

  • Seo, Bo Yoon;Jung, Jin Kyo;Park, Ki Jin;Cho, Jum Rae;Lee, Gwan-Seok;Jung, Chung Ryul
    • Korean journal of applied entomology
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    • v.53 no.3
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    • pp.247-260
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    • 2014
  • To identify the species of Trichogramma occurring in the corn fields of Korea as egg parasitoids of Ostrinia furnacalis, we sequenced the full-length of ITS2 nuclear rDNA from 112 parasitoids collected during this study. As a reference to distinguish species, we also retrieved full-length ITS2 sequences of 60 Trichogramma species from the NCBI GenBank database. On the basis of the size and 3'terminal sequence pattern of the ITS2 sequences, the Trichogramma samples collected in this study were divided into three groups (K-1, -2, and -3). Evolutionary distances (d) within and between groups based on ITS2 sequences were estimated to be ${\leq}0.005$ and ${\geq}0.080$, respectively. In the net average distance between groups or species, the d value between K-1 and T. ostriniae, K-2 and T. dendrolimi, and K-3 and T. confusum was the lowest, with values of 0.016, 0.001, and 0.002, respectively. In the phylogenetic tree, K-1 and K-2 were clustered with T. ostriniae and T. dendrolimi, respectively. However, K-3 was clustered with three different species, namely, T. confusum, T. chilonis, and T. bilingensis. NCBI BLAST results revealed that parasitoids belonging to K-1 and K-2 showed 99% identity with T. ostriniae and T. dendrolimi, respectively. Parasitoids in K-3 collected from Hongcheon showed 99-100% identity with T. confusum and T. chilonis, and one parasitoid in K-3 collected from Gochang had 98% identity with T. bilingensis, T. confusum, and T. chilonis. On the basis of these results, we infer that the species of Trichogramma collected in this study are closely related to T. ostriniae (K-1) and T. dendrolimi (K-2). However, it was not possible to distinguish species of K-3 using the ITS2 sequence alone.

Changing patterns of infection with digenetic larval trematodes from Iresh-water fish in River Taewha, Kyongnam Province (경남 태화강에서 채집된 담수어에 있어서 흡충류 피낭유충 기생상의 변화)

  • 주종윤
    • Parasites, Hosts and Diseases
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    • v.26 no.4
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    • pp.263-274
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    • 1988
  • Recent patterns of infection with digenetic larval trematodes in fresh- water and brackish-water ask were studied in three locations of the river Taewha during the period from April to October, 1988, and compared with the data reported previously in the same river, 0(16 species of fish examined, the encysted larvae of Cyathocotyle orientalis were found most frequently from 9 species of fresh.water fish. The metacercariae of Echinochasmus sp. , Metacercaria hasegawai and Metagonimus yokogawai were found from 8 species, those of Clonorchis sinensis from 7 species, and Exorchis oviformis and Metorchis orientalis from 5 species of fish. The infection rates of fish with C. sinensis metacercariae were not lower than those reported in 1980, whereas their intensity of infection was found lowered in 3 species, Ccreobagrus brevicorpus, Gnathopogon atromaculatus, and Funtungia herzi. The infection rates of 3 species of fish with M. yokogawai metacercariae were lower than the results in 1982, while the rate was higher in 2 species, Zacco platypus, and Z. temmincki, and rather stationary in Flecoglossus altivelis. The intensity of infection in several species of fish appeared rather higher than in 1980. The encysted larvae of C. orientalis, Echinochasmus sp., E. oviformis and Metacercaria hasegawai showed variations in infection rates of fish in 1980 and in the present study. It was found that the rate of infection with digenetic larval trematodes in fresh- water fish was still relatively high in the river Taewha, and the metacercarial burden in the fish varied greatly by different fish in 1980 and in the present study.

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Broadband Improvement of The Rectangular Microstrip Patch Antennas (구형 마이크로스트립 패치 안테나 대역폭 개선)

  • 이현지;임영석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.7B
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    • pp.875-879
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    • 2001
  • 마이크로스트립 패치안테나의 대역을 증가시키는 방법이 꾸준히 연구되고 있다. 본 연구에서는 구형 패치 구조에 기생 소자를 더한 형태로 구형 패치 외부에 바(bar)와 밴드(band) 모양의 기생소자를 설치하여 프린징 효과를 최소화 하고자 하였으며, 이로 인한 안테나 효율의 향상과 대역폭을 증가를 시키고자 하였으며, 또한 기생소자의 폭과 방사안테나의 간격을 조절하여 대역폭과 임피던스정합 특성의 변화를 해석하였다. 이를 이용하여 LMDS통신 주파수 대역인 24.6GHz∼28.5GHz에서 공진 대역을 갖도록 설계하였다. 정재파비 2.0 이하를 기준으로 기존의 패치안테나의 중심주파수에 대한 대역 이용율이 수 %인데 반하여, 본 연구에서 제시한 밴드를 설치한 구조의 경우 12.92%로 증가함을 알 수 있고, 또한 본 연구에서 제시한 외부 밴드를 갖는 구조가 급전선로와 패치 안테나와의 정합특성이 월등함을 확인하였다.

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A report on Acanthochondria spirigera from the gills of Lophiomus setigerus in the southern coast of Korea (남해안 아귀(Lophiomus setigerus) 아가미에 기생하는 Acanthochondria spirigera에 관하여)

  • Choi, Sang-Duk;Hong, Sung-Yun;Jung, Choom-Goo
    • Journal of fish pathology
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    • v.9 no.2
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    • pp.127-135
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    • 1996
  • Acanthochondria spirigera is redescribed based on the specimens recovered from the Lophiomus setigerus in the southern coast of Korea. This parasitic copepoda is distinguished from congeners by the possession of spirally twisted egg-strings. Acanthochondria spirigera(Chondracanthidae, Poecilostomatoida) is the first recorded species from Korea. This parasitic copepod was not found on the fish in May. Relative density and prevalence also decreased from January to May. A. spirigera live symbiotically within the pharyngeal cavity of the L. setigerus, and eat oesophageal mucous string of their hosts. The male of the parasitic copepoda is dwarf, and found on the ventral surface of genital segment of the female.

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