• 한국가축번식학회지
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• 제16권4호
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• pp.335-340
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• 1993

The development of efficient method for the production of transgenic mice has been investigated in our laboratory. This study was conducted to develop the artificial insemination in the mouse. Spermatozoa were collected from the cauda epididymis of ICR males(age:12~15 weeks, Body weight : 30g) and artificially inseminated into the intrauterine via cervix of hormone-primed ICR females(age: 6~8 weeks, body weight: 25g) using the capillary tube, 200~300 $\mu$m in inner diameter. The effect of concentration of sperm(80$\times$104, 40$\times$104, 20$\times$104, 10$\times$104, 5$\times$104, 3$\times$104, 1$\times$104/20${mu}ell$. The artificial insemination was succeeded but fertilization rate was very low(5~15%) compared to the natural mating and 59 normal youngs born from 60 females. Therefore, our findings suggest that it is possible to produce the great number of mice from the same orgin of male by artificial inseminatin. However, the lower pregnancy rate has to be solved to used broadly the artificial insemination in mouse.

• 한국생태학회:학술대회논문집
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• 한국생태학회 2002년도 VIII 세계생태학대회
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• pp.133-139
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• 2002

Regeneration process of the Korean beech (Fagus multinervis Nakai) forest was studied in relation to the distributional pattern and age structure. In this study, it was clarified that the Korean beech forest is regenerated in both way: seedlings(sexual reproduction) and sprouts(vegetative reproduction) formations. In the large gaps, seedling may be established, resulting in clusters of even-aged individuals. But in the small-sized gaps, there may filed by the extention of surrounding trees and/or by the young trunks, which have sprouted from the base of stumps. As most gaps in the F. multinervis forest were derived from falling of a single stem, regeneration by sprouts seems to be more common than that by the seedlings.

• The Korean Journal of Ecology
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• 제25권4호
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• pp.267-273
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• 2002

Regeneration process of the Korean beech (Fagus multinervis Nakai) forest was studied in relation to the distributional pattern and age structure. In this study, it was clarified that the Korean beech forest is regenerated in both way: seedlings(sexual reproduction) and sprouts(vegetative reproduction) formations. In the large gaps, seedling may be established, resulting in clusters of even-aged individuals. But in the small-sized gaps, there may filled by the extention of surrounding trees and/or by the young trunks, which have sprouted from the base of stumps. As most gaps in the F. multinervis forest were derived from falling of a single stem, regeneration by sprouts seems to be more common than that by the seedlings.

• 한국동물생명공학회지
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• 제37권1호
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• pp.13-16
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• 2022

The use of animals heavily impacts the mental health of researchers performing the animal experiments. The animal researchers need to take care of animals but also give pain and sacrifice them at the same time. This circumstance can cause a variety of mental stress to the researchers. The stress generated in the laboratory would not only negatively affect the management of animals and the research results, but also would harm the researchers' physical and mental health. Because the feeling of sympathy for animals is a natural feature of humanity, psychological stress following a laboratory animal's death after use is not surprising. It is necessary to revise the relevant laws based on understanding the difficulties of animal researchers in society and to develop related educational programs at the national level to help the psychology and emotions of researchers who conduct animal experiments.

• 한국가축번식학회지
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• 제27권4호
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• pp.287-297
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• 2003

The aim of this review is to give insight into the reproduction potential of the Korean native goat(KNG) doe. The mean age of the first estrus in the KNG doe is 141.24$\pm$18.l7 days. The length of the estrous cycle was recorded as being 20.58$\pm$2.63 days, with the mean duration of estrous period being 17.8$\pm$7.3 to 32.9$\pm$1.2 h, and the duration of the post-partum anestrous period being 13.4(9 to 18) to 30.1$\pm$3.8 days in the KNG doe. The ages at first delivery are 10 to 12 months(56.3％) in the KNG doe. The KNG does are no restricted breeding season, because estrus and kiddings are observed throughout the year. The mean gestation period of the KNG doe is recorded as being 150.69$\pm$6.14 days with parities having no significant effect on gestation length. The mean interval between parturitions in the KNG doe is 207.78$\pm$1.72 days with parities and birth type having no significant effect on kidding intervals. The mean litter sizes at birth in the KNG doe are 1.69$\pm$0.03 heads, and litter size at birth was affected (P<0.05) by parity. The mean birth weight of kid in the KNG is 2.04$\pm$0.30 kg with a variety as being 2.28$\pm$0.26, 2.11$\pm$ 0.30 and 1.64$\pm$0.19 kg for singles, twins and triplets over of birth type, respectively. The mean mortality of 635 kids in the KNG is 23$\pm$1 ％ with a variety as being 28$\pm$3, 21$\pm$2, 16$\pm$3 and 46$\pm$15 ％ for singles, twins, triplets and quadruplets of birth type, respectively.

• ALGAE
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• 제32권4호
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• pp.337-347
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• 2017

Silvetia siliquosa is an ecologically and commercially important brown alga that is harvested from its natural habitats, but its population has recently been diminishing along the Korean coast. To develop new techniques for algal population restoration, we tested two newly developed transplantation methods (using polyethylene ropes and natural rock pieces) at two study sites, Gwanmaedo and Yeongsando, on the southwest coast of Korea, from May to November 2014. The transplants on polyethylene ropes showed significantly greater survival, maturity, and growth than those on natural rocks at both study sites. Newly recruited juveniles (<3 cm) of S. siliquosa increased remarkably from May to December near the transplants on polyethylene ropes and natural rocks.Therefore, we suggest that transplantation using polyethylene ropes is more effective than using natural rocks to restore the population of S. siliquosa in Korea.

• Animal Systematics, Evolution and Diversity
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• 제24권3호
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• pp.251-263
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• 2008

Eight species and four genera belonging to two families of antipatharians have been reported in Korea. In the present study, the major specimens were collected from the coastal areas of Jejudo Island from 2005 to 2006, and the other ones which have been deposited in the Natural History Museum and the Department of Life Science, Ewha Womans University during the period from 1965 to 2004 were reexamined. As a result of this work, four species, Myriopathes bifaria, M. stechowi, M. ulex and Plumapathes pennacea are new to Korean antipatharian fauna. In this study, total six species including previously recorded species of the family Myriopathidae were described. And the distribution range of Myriopathes lata was turned out to be expanded from southwestern sea to the eastern sea, up to Ulleungdo Is. of Korea. Especially, the sexuality and the gonadal stage of M. lata which are collected during their reproduction period were also determined by means of histological analysis.

• 한국해양공학회지
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• 제24권6호
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• pp.109-113
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• 2010

We present the minimum weight optimum design of cross sectional for frame structures subject to natural frequency. The optimum design in this paper employ discrete and continuous design variables and Genetic Algorithms. In this paper, Genetic Algorithms is used in optimization process, and be used the method of Elitism and penalty parameters in order to improved fitness in the reproduction process. For 1-Bay 2-Story frame structure, in examples, continuous and discrete design variables are used, and W-section (No.1~No.64), from AISC, discrete data are used in discrete optimization. In this case, Exhaustive search are used for finding global optimum. Continuous variables are used for 1-Bay 7-Story frame structure. Two typical frame structure optimization examples are employed to demonstrate the availability of Genetic Algorithms for solving minimum weight optimum of frame structures with fundamental and multi frequency.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2001년도 추계정기 학술발표회 초록집
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• pp.5-10
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• 2001

It is necessary for governmental supporting polices to collect. management and maintain the genetic resource with respects of diversity of useful natural resource plant and domestic variety for plant industry. There are the main tasks of functional plant industry to develope the techniques of systemic management of genetic resources with sufficient life because of having the key of human's fate with life and death and being the valuable thing to be Investigation. collection and introduction of genetic resource with natural resource plants. Agriculture after WTO is putting an emphasis on the development of functional plants with highly competitiveness In world market under long term and organizing plants Genetic resource of plant in the official institution are maintaining and managing to be possible the regeneration and reproduction if necessary. and utilizing whoever need them.

• 한국발생생물학회지:발생과생식
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• 제21권4호
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• pp.449-456
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• 2017

The germline stem cells of the Drosophila ovary continuously produce eggs throughout the life-span. Intricate regulation of stemness and differentiation is critical to this continuous production. The translational regulator Nos is an intrinsic factor that is required for maintenance of stemness in germline stem cells. Nos expression is reduced in differentiating cells at the post-transcriptional level by diverse translational regulators. However, molecular mechanisms underlying Nos repression are not completely understood. Through three distinct protein-protein interaction experiments, we identified specific molecular interactions between translational regulators involved in Nos repression. Our findings suggest a model in which protein complexes assemble on the 3' untranslated region of Nos mRNA in order to regulate Nos expression at the post-transcriptional level.