• 한국수산과학회지
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• 제36권5호
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• pp.480-485
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• 2003

Morphology of the spermatozoa from the testes of the catfish (Pseudobagrus brevicorpus) was studied by transmission and scanning electron microscopy. The spermatozoa of P. brevicorpus are approximately $82.25\pm0.06\;{\mu}m$ in length and relatively simple cells composed of a spherical head, a short midpiece and a tail as in most teleost fish, The nucleus measuring about $2.00\pm0.02\;{\mu}m$ in length is depressed with a deep nuclear fossa of about $1.05\pm0.03\;{\mu}m$ in length three fifths of the nuclear length. The nuclear fossa contains the proximal and distal centrioles. The two centrioles are oriented approximately $150^{\circ}$ to each other. The mitochondria are arranged in two layers and their number is 12 or more. They are separated from the axoneme by the cytoplasmic canal. The axoneme is the 9+2 microtubular pattern and has inner but no outer dynein arms as in other bagrids. The axonemal fins were the closed to axonemal doublet 3 and 8. The axonemal fins and lost outer dynein arm are shared in Bagridae and the deep nuclear fossa is shared in Siluriformes. The axonemal fins observed in Bagridae and Amblycipitidae of Siluriformes might be the apomorphic character in Ostariophysi.

• 한국토양동물학회지
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• 제7권1_2호
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• pp.45-49
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• 2002

골프장에 재식된 들잔디, Zoysia japonica에서 피해 원인을 조사하던 중 뿌리혹선충이 다수 기생하고 있었다. 이 선충의 가해특성과 형태적 특징을 조사하였다. 이 선충은 뿌리에 혹을 형성하지 않으며, 뿌리 겉으로 후반부를 드러낸 암컷은 난낭을 형성하고 있다. M. marylandi의 주요 특징으로는, 암컷의 경우 Perineal 패턴은 둥글며 높게 위치하여 있고, 음문과 항문은 함몰되어 있으며, 물결 모양의 주름은 거칠며 넓게 공간을 형성하고 있다. 유충의 체장은 390.3 $\mu\textrm{m}$ (290-430), 꼬리 길이는 55.1 $\mu\textrm{m}$ (49-59)이며, 4개의 측선을 이룬다 수컷의 구침길이는 18.1 $\mu\textrm{m}$ (15-24), 교접자 길이는 26.2 $\mu\textrm{m}$ (23-29)이며, 4-5개의 측선수를 가진다.

• Animal Systematics, Evolution and Diversity
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• 제37권3호
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• pp.205-211
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• 2021

This study investigates the morphological and skull characteristics of the Siberian weasel Mustela sibirica quelpartis from the Jeju Island, South Korea. A total of 26 roadkill specimens (22 males and 4 females) were collected from October 2012 to April 2016. All collected specimens were examined for morphological characteristics, but only 19 specimens (16 males and 3 females) were in a good enough condition to process for skull measurements. This study showed no significant differences in ear length between male and female (p>0.05), and significant differences were found in head-body length, tail length (TL), and hind-food length (p<0.05). Both the male and female of M. s. quelpartis were larger in its external characteristics except for TL than M. s. coreanus living in the mainland of South Korea. M. s. quelpartis males have a smaller skull size than their female counterparts. In general, both male and female M. s. quelpartis showed external characteristics in line with the Island Rule. The findings of this study are important in order to shed more light on the evolutionary mechanism of small mammals living on the Jeju Island.

• 한국환경생태학회지
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• 제28권5호
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• pp.542-549
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• 2014

이 연구는 2006년 5월부터 2009년 6월까지 제주도와 작은 부속섬인 가파도 두 지역에 서식하는 쇠살모사 개체군간 몸의 크기와 성적크기이형 및 이에 따른 환경요인을 밝히고, 종 다양성 유지에 필요한 자료를 제공하기 위하여 이루어졌다. 연구결과, 제주도 개체군의 몸길이는 암컷 242-532mm ($422.0{\pm}46.7mm$, n = 100), 수컷 296-580mm ($434.5{\pm}51.7mm$, n = 63)이었고, 가파도 개체군의 몸길이는 암컷 205-395mm ($335{\pm}43.6mm$, n = 55), 수컷 215-430mm ($328{\pm}39.4mm$, n = 73)으로 암수 모두 제주도 개체군이 가파도 개체군에 비해 큰 것으로 나타났다(암컷 t = 17.343, df = 115, P<0.001; 수컷 t = 19.128, df = 101, P<0.001). 성적크기이형 지수(SSD)는 제주도 개체군이 -0.03으로 수컷이 다소 크고, 가파도 개체군은 0.02로 암컷이 다소 컸다. 이처럼 제주도 개체군과 가파도 개체군이 몸의 크기에 있어 차이가 나타나는 것은 서로 다른 환경에 적응된 결과라 판단된다. 또한 두 지역 개체군 및 새끼의 성적크기이형은 제주도 개체군의 몸길이는 수컷이 암컷보다 다소 컸으나(t = -2.011, df = 117, P<0.05), 가파도 개체군과 새끼에서는 유의한 차이가 없었다. 제주도 개체군에서 머리 길이(F = 6.318, $df_{1,2}$ = 1,117, P<0.05), 머리 폭(F = 8.090, $df_{1,2}$ = 1,117, P<0.01), 눈 사이 거리(F = 15.898, $df_{1,2}$ = 1,117, P<0.001) 및 꼬리 길이(F = 238.488, $df_{1,2}$ = 1,111, P<0.001)에서 수컷이 암컷보다 컸으며, 체중은 암컷이 수컷보다 무거운 것으로 나타났다(F = 64.111, $df_{1,2}$ = 1,114, P<0.001). 가파도 개체군에서는 머리 길이, 머리 폭, 눈 사이 거리에서는 암컷과 수컷 간에 유의한 차이는 없었고, 꼬리 길이에서 수컷이 암컷보다 길었으며(F = 168.555, $df_{1,2}$ = 1,74, P<0.001), 체중은 암컷이 수컷보다 무거운 것으로 나타났다(F = 17.812, $df_{1,2}$ = 1,76, P<0.001). 새끼에서는 머리길이, 머리 폭, 눈 사이 거리에서 유의한 차이가 없었으나, 꼬리 길이(F = 67.793, $df_{1,2}$ = 1,72, P<0.001)와 체중(F = 4.558, $df_{1,2}$ = 1,72, P<0.05)에서 수컷이 암컷보다 크게 나타났다. 새끼에서 성적크기이형 현상이 나타나지 않았던 몸길이, 머리길이, 머리 폭 및 눈 사이 거리가 제주도 개체군에서는 모두 수컷이 암컷보다 큰 것으로 나타나 제주도 개체군에서의 성적크기이형 현상은 성장과정에서 생기는 것이라 판단된다.

• 방사선산업학회지
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• 제8권2호
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• pp.89-95
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• 2014

This study was conducted to determine the optimal dose of gamma-ray on the growth and nucleus DNA damage for mutation breeding in licorice. Gamma-rays irradiated to dry seeds with various doses (0 to 1000 Gy). Significant decreases in germination rate (%), survival rate (%) and growth characteristics (plant height, number of leaves, root length and fresh weight) were observed by dose of increased. $LD_{50}$ (lethal dose) was approximately 400 Gy to 500 Gy. Also, reduction doses ($RD_{50}$) of plant height, number of leaves, root length and flash weight were 428 Gy, 760 Gy, 363 Gy and 334 Gy, respectively. It is supplest that the optimal dose of gamma irradiation for licorice mutation induction might be about 400 Gy in this study. We also conducted comet assay to observe nucleus DNA damage due to gamma irradiation. In comet assay, a clear difference was identified over 300 Gy treatments. With increasing doses of gamma-ray in the range of 100 to 1000 Gy, the rate of head DNA was decreased significantly from 92.88% to 73.09%. Tail length(${\mu}m$) was increased as the dose of increased over 300 Gy. Growth characteristics (Germination rate, Survival rate, plant height, number of leaves, root length and fresh weight) were highly negatively ($P{\leq}0.01$) correlated with dose. While the tail length was highly positively ($P{\leq}0.01$) correlated with dose.

• 한국발생생물학회지:발생과생식
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• 제24권1호
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• pp.63-70
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• 2020

This study aimed to investigate early life of Coreoperca herzi living in Han River and compare morphological differences between different groups during the development in order to provide basic data for relevant taxonomic research. On average, one female individual spawned 541 to 861 eggs (average 701) at once. After 259 hours, the tail broke out of the egg membrane and hatching began. Immediately after hatching, the larvae were average 7.81±0.10 mm (n=5) in total length. 60 days the juvenile was average 35.9±1.30 mm (n=5) in total length. The white spots spread to the rest of the body, rending the same pattern as that on the body of their broodstock fish.

• Asian-Australasian Journal of Animal Sciences
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• 제23권10호
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• pp.1282-1290
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• 2010

The study was carried out to assess the developmental abnormalities induced by Cytotec in mice during intrauterine life. Pregnant mice were exposed to a single dose of 0, 0.02, 0.04, 0.06, 0.08 and $0.1{\mu}g$/g BW on day 8 of gestation. Fetuses were recovered on day 18 of gestation. These fetuses were subjected to morphological and morphometric studies. Morphological studies showed abnormalities like anophthalmia, microophthalmia, micromelia and syndactyly. In addition to these, resorptions were also encountered in the higher dose groups. Morphometric analysis showed an overall reduction in body weight, crown rump length, brain and eye circumference, pinna and snout size, length of fore and hind limb and tail size with a significant difference (p<0.001) compared to controls. The outcomes of histological studies revealed some brain defects like hydrocephaly, enlarged third ventricle and undifferentiated ectoneural cells and abnormalities of the heart included right auricle thrombosis and degeneration of trabecular zone.

• 한국응용곤충학회지
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• 제53권1호
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• pp.51-57
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• 2014

최근 5년 동안 식물검역 현장에서 검출된 뿌리썩이선충속 선충을 분류하여 Pratylenchus crenatus, P. fallax, P. kumamotoensis, P. panamaensis, P. penetrans로 동정하였다. 이 종들의 진단형질은 구순부의 주름 수, 두부의 형태, 구침의 길이, 수컷의 유무, 측대의 구조, 수정낭의 형태, 후부자궁낭의 길이, 미부의 형태 등을 포함한다. 이들의 사진과 측정치 및 형태적 특징을 기술하였다.

• 대한전기학회논문지
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• 제45권2호
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• pp.289-293
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• 1996

The basic study on laser triggered lightning was carried out for the active protection of lightning in power transmission system. The lengths of generated plasma channels were simulated numerically for variations of energy and pulse width of CO$_{2}$ laser by Runge-Kutta-Gill method. As results, the effective lengths of plasma channels were 2.3m, 2.67m and 3.4m respectively for energy of 45J, 60J and 100J of CO$_{2}$ laser pulse with pulse width of 50nsec using focusing mirror with focal length of 10m. And also the effects of pulse width of first pulse and tail pulse of CO$_{2}$ laser on the length of plasma channel were examined.

• Molecular & Cellular Toxicology
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• 제4권3호
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• pp.211-217
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• 2008

To clarify the DNA damage from reactive oxygen species, we measured the DNA damage through Fpg/Endo III FLARE (Fragment Length Analysis with Repair Enzyme) assay and real time RT-PCR. The 80 SD rats assigned to 4 dose groups exposed to cumene vapor for 90 days. With Fpg/Endo III FLARE assay in hepatocytes, we found the OTM (Olive Tail Moment) and TL (Tail Length) significantly increased in no-enzyme treated and Fpg-treated control and 8 ppm groups with 28 days exposure. In Endo III-treated 8 ppm group, significantly increased the values with 90 days exposure. With lymphocytes, it was founded the values significantly increased in no-enzyme treated 800 ppm group in 28 and 90 days. It was significantly increased in Endo III-treated 80 ppm for 28 days and 800 ppm for 90 days. From the above findings, FLARE assay was suggested as being available as a biological marker for DNA damage induced by cumene exposure in SD rats. And we used real time RT-PCR for the OGG1 mRNA expression, it had dose-dependent biologic effects in 1 day exposure, but decrease the levels of rOGG1 mRNA. Our findings provide evidence that cumene exposure may cause suppression of rOGG1 in the rat hepatocytes or lymphocytes.