• Applied Microscopy
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• v.15 no.1
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• pp.86-100
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• 1985

A observation of the ovarian development and oogenesis of Pieris rapae Linne has been carried out during metamorphosis using stereo-microscope, light microscope and electron microscope. The results obtained through this experiment are as follows: 1. The ovarian development and vitellogenesis begin at the 3-day old pupa and the 6-day old pupa respectively, and the adult ovary right after their emergence contains a few mature eggs. 2. The species described above are further observed at six different stages in oogenesis, and the results are summarized as follows. 1) Pieris rapae has polytrophic ovarioles. The cell organelles of the nurse cells are transfered to the oocyte through the ring canal at the early oogenesis. 2) At stage 2, the nuclear envelope of oocyte nucleus is less infolding than that of nurse cell nucleus. In the oocyte cytoplasm a large number of ribosomes are observed. 3) At stage 3 and 4, many micropinocytotic vesicles are observed in the oocyte cytoplasm. These vesicles are fused together to form large proteid yolks. 4) At stage 5, the vitelline membrane is laid down in the intercellular space between the follicle cells and oocyte. 5) At stage 6, the chorion is formed by the follicle cells. 6) A micropyle and a number of aeropyle are observed on the surface of a mature egg.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.36-40
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• 1989

The eels, Anguilla japonica, were reared in a tank with daily feeding for up to 97 days, and otoliths were regularly collected for the observation of their microstructures. Microscopic observation of the thin-sectioned otolith under dark field provided significant information on daily growth increments as well as the difference in visual contrast shown by the increments. Clearly defined elver mark formed during the metamorphosis from leptocephalus to the elver can be considered as the origin of the age for the sedentary yellow eel in continental water. The close correspondence between the number of increments outside elver mark and chronological age in days from the beginning of feeding indicates that increment deposition on a daily basis was initiated with the start of feeding for the sedentary yellow eel. Either 7 or 14 daily growth increments were grouped together into 2 alternative units, each distinguished by prominent checks or by visual contrast. The absence of any apparent environmental variations with 7 or 14 day period in the reared tank implies that the phase of the moon could be a zeitgeber for the endogenous rhythm.

• The Korean Journal of Zoology
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• v.24 no.1
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• pp.27-37
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• 1981

Protein patterns at various stages of pre-and post-fertilization in Drosophila melanogaster were analyzed using polyacrylamide gel electrophoresis. Ovaries at various times after hatching, embryos, larvae and pupae were collected and used for protein analysis. The protein patterns were found to vary qualitatively and quantitatively during oogenesis as well as during embryogenesis and metamorphosis. Yolk proteins, which were found to be synthesized in fat body and transferred into the oocytes, appeared in three bands in the gel in the early stages, but these proteins seemded to be converged into a single band in the late stage of oogenesis. The protein patterns in the post fertilization stages seemed to be abruptly changed at two different stages; between embryonic and larval stages and between the second and third instar stages. The pattern in the pupal stages was not very much different from that of the third instar.

• The Korean Journal of Zoology
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• v.16 no.2
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• pp.139-145
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• 1973

The activity of acid and alkaline phosphatases of pine moth, Dendrolimus spect abilis Butler was measured in a serier of developmental stages ranging from the larva to the adult. The activity of both enzymes increased gradually with age of larvae, and then decreased in the prepupal stage. Acid enzyme was at a maximum in the pupal early stage and alkaline enzyme in the 8th instar larva, respectively. And in the prepupal stage there were no significant differences between both acid and alkalnie phosphatases. However, their activities were far lower than in the 8th instar larva. In the pupal early stage there occurs a increase in the acitivity of acid enzyme followed by a decrease in the pupal later stage, and in the adult stage its activity increased again.

• The Korean Journal of Zoology
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• v.29 no.4
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• pp.261-271
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• 1986

The cutaneous xanthophore differentiation from larvae to adult in Bombina orientalis-the Korean fire bellied toad-is studied with light and electron microscopes. General structure of adult xanthophore which is composed of many pterinosomes and a small quantity of carotenoid vesicles is forming chromatophore complex with other dermal pigment cells. And the cytoplasmic process of xanthophore is distributed just beneath the basement membrane. The first differentiated xanthophore is originated from both rER rich cells and Golgi complex rich cells before and after the feeding larval stage. Formation of the pigment granule is proceeded gradually along the sequental metamorphic stages. After the metamorphosis, rapid multiplication of pterinosome is observed and enlargement of carotenoid vesicle is appeared after hybernation. These pigment granules are seen several structures by the differentiated level.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.12-15
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• 2003

The effects of the non-steroidal ecdysteroid agonist tebufenozide on larvae of C. faviplumus and C. riparius were tested in the laboratory. In the most treatments it reached a statistically significant difference from the control condition. As the concentration of tebufenozide was increased, a relatively larger proportion of the observed mortality was associated with the metamorphosis and molting process. Also, the larval mortality of the first larvae was higher than the fourth-instar larvae in C. riparius. In terms of development, the effects of tebufenozide were delayed growth stage in relatively lower concentration such as 10 $\mu\textrm{g}$/L treatments. Based on the mortality, the susceptibility followed the first-instar C. riparius > the fourth-instar C. flaviplumus > the fourth-instal C. riparius. The morphological effects showed that the first and second segments of body of exposed larvae with tebufenozide expanded slowly and not made a complete cephalothorax of pupae during long times or days. And the head capsule slipped down and forward, revealing a fragile and non-pigmented, unsclerotized new head capsule. There was obvious significant difference in the male/female ratio in contaminated fourth larvae of C. riparius. Also, due to the different emergence periods of male/female in low insecticide concentrations, mating chances or opportunities of insects should be decreased. Accordingly, ecological strategies for keeping of sustainable populations should be disrupted.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.144-151
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• 2014

Recently, according to the advances of vehicle manufacturing technology and the fuel-efficient vehicles, the weight of the vehicle body has been reduced and quietness of the vehicle has been increased. So that, as the emotional qualities of cars, such as NVH, are emphasized in recent years. Also required to be established of the effective measure for brake Judder. The Judder was caused by the increase in DTV by the uneven thermo metamorphosis of brake disc and the partial abrasion of disc. In this study, the disc aggression by friction materials was confirmed and the improving methods of friction materials in connection with the abrasive characteristics reviewed of $ZrSiO_4$ each particle size(under $3{\mu}m$, $5{\sim}10{\mu}m$ and over $15{\mu}m$). In addition, the study is institute make use of limit for $ZrSiO_4$ raw-material particle size and vol% in friction materials. At the result, the optimum size of $ZrSiO_4$ particles was confirmed about 5 to $10{\mu}m$.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.06a
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• pp.133-140
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• 1999

In this paper, we propose a method of image-based three-dimensional modeling for realistic facial expression. In the proposed method, real human facial images are used to deform a generic three-dimensional mesh model and the deformed model is animated to generate facial expression animation. First, we take several pictures of the same person from several view angles. Then we project a three-dimensional face model onto the plane of each facial image and match the projected model with each image. The results are combined to generate a deformed three-dimensional model. We use the feature-based image metamorphosis to match the projected models with images. We then create a synthetic image from the two-dimensional images of a specific person's face. This synthetic image is texture-mapped to the cylindrical projection of the three-dimensional model. We also propose a muscle-based animation technique to generate realistic facial expression animations. This method facilitates the control of the animation. lastly, we show the animation results of the six represenative facial expressions.

• Korean Journal of Human Ecology
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• v.9 no.4
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• pp.27-39
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• 2006

Surrealism, appeared in the beginning of the 20th century and affected almost all art fields, is one of the most representative art trends. Surrealism, not restricted from any rules and traditions but tried to produce a new appreciations in the world of dream and unconsciousness, also has affected fashion. In this paper, I have tried to find out how the surrealism has been expressed in the modern fashion, especially in Thierry Mugller's design. Thierry Mugler is one of the most famous designers who have expressed surrealism in their fashion designs. I have classified his designs and researched them by the application into the human body and the nature, by the metaphor and transformation of things, and by the metamorphosis of location and an optical illusion. It was based on Depaysement which is one of the ways in surrealistic expressions. The result of the study is followings; First, surrealism made fashion design possible to creat unlimitedly and sublimated it anew modern beauty by attempting the varieties of the fashion, not restricted from any rules and traditions. Second, surrealism made the general public to complete anew recognition and valuation about fashion by expressing the external character and the internal meaning on the clothes. Third, surrealism made people to recognize, which clothes is not simply wearing thing but also one of the art expression forms.

• Animal cells and systems
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• v.11 no.1
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• pp.23-31
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• 2007

Programmed cell death was characterized in the silkworm thoracic ganglia TG1, TG2 and TG3 during postembryonic periods by TUNEL assay. Apoptotic cells were detected in the three TGs of all larval stages except for day-1, 2 1st instar larvae, in which no apoptotic cells were found. From day-7 5th larva, the numbers of apoptotic cells were dramatically increased and peaked on day-1 pupa and day-2 pupa and then abruptly decreased. Apoptotic cells finally disappeared in day-1 adult. In-vivo injection of 20-hydroxyecdysone (20E) into day-8 5th larva resulted in a striking decrease of apoptotic cells. Actinomycin D (Act D) or cycloheximide (CHX), injected into hemolymph of day-8 5th larva, resulted in a decrease of apoptotic cells in the three TGs. Injection of caspase-8 and -3 inhibitors also blocked cellular apoptosis. These results will provide valuable information for understanding of cellular changes in the three TGs during metamorphosis of the insect species.