• Korean Journal of Ichthyology
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• v.31 no.1
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• pp.1-6
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• 2019

The spermatozoa of Hemiculter eigenmanni is similar to other cyprinid by spherical head containing a nucleus with highly condensed chromatin, a short midpiece with mitochondria and a flagellum located tangentially to the head. The fine structure of cyprinid spermatozoa described classical characteristics of Cyprinidae spermatozoon comprising the absent of acrosome, the shallow nucleal fossa, postnuclear distribution of mitochondria and the lateral insertion of flagellum. However there were some structural differences for their morphology, in the mitochondria and the orientation of centrioles. The proxomal and distal centrioles are oriented approximately $145^{\circ}$ to each other. The mitochondria of 8 or 10 in number are arranged in two or three layers.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.17-17
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• 2001

착상전 수정란 단계에서 형질전환 수정란의 선발은 형질전환동물의 효율을 증대시킬 수 있는 방법이다. 성공적인 형질전환동물의 생산을 위해서는 생산된 수정란의 mosaicism 빈도를 감소시켜 전체 할구에서의 유전자 발현을 유도하는 것이 최적일 것이다. 따라서 본 연구에서는 돼지의 웅성 생식세포를 이용한 형질전환동물의 생산에 있어서 다양한 정자세포 이용시 형질전환 수정란의 생산성 및 mosaicism 빈도를 조사하였다. 아울러 돼지 웅성생식세포내 GFP 유전자도입시 세포들의 생존율 및 원형정자세포분리 후 배양에 따른 형태적 변화를 관찰하였다. 돼지의 웅성 생식세포내 GFP 유전자 도입은 전기자극법 (1.3 ㎸/cm, 200 $\mu\textrm{s}$) 에 의하여 수행되었으며, 이 때 생존율은 60-70%이였다. 유전자가 도입된 전체 세포중 원형정자세포군의 분리는 유식세포분리기에 의하여 수행하였으며, 전체집단에 대한 분리군의 비율은 평균 16.2%이였다. 형질전환 수정란의 생산은 정자 (ICSI), 원형정자세포 (ROSI), 배양후 확장된 원형정자세포(ELSI)를 이용하였으며 각각의 난할율은 ICSI (82.9%), ROSI (59.1%), ELSI (62.1%)로 유의한 차이를 나타내었다. 그리고 8세포기까지의 배발달율은 각각 61.1, 40.9 및 48.6%이였으며, 상실배 및 포배기형성율은 각각 24.6, 18.1 및 32.4%이였다. 형광현미경하에서 GFP 단백질이 발현된 8세포기 수정란을 대상으로 각각의 할구를 primer extension pream-plification (PEP) PCR 방법으로 분석한 결과, ICSI 및 ROSI 실시후 대부분 (15/20, 9/10) 의 수정란은 3~4개의 할구에서만 GFP 유전자의 존재여부를 확인할 수 있었으며, 전체 할구에서 GFP 유전자가 모두 확인된 수정란은 없었다. 반면에 배양된 확장 원형정자세포를 이용하여 생산한 수정란의 경우, 4/10 (40%)에서 전체 할구내에 GFP 유전자의 존재를 확인할 수 있었다. 이러한 결과는 비록 배발달율 및 GFP 유전자 발현율에 있어서는 ELSI방법이 ICSI 등의 방법보다 현저히 낮았지만, mosaicsism 빈도가 낮아 바람직한 형질전환 수정란 생산에서는 오히려 유용한 방법이라고 사료된다. 또한 외래 유전자의 도입효율 면에서 후기 원형정자나 성숙정자보다 초기 원형정자세포에 외래유전자를 도입한 다음, 성숙시킨 확장원형 정자세포를 이용하는 방법이 보다 우수하다는 것을 시사하였다. 따라서 본 연구결과는 포유동물의 웅성 생식세포를 이용하여 nonmosaicisn을 나타내는 형질전환수정란을 생산하고 선발할 수 있는 일련의 기술적 과정을 정립하였다고 사료된다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.246-247
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• 2000

수서동물 생식소의 해부학적 구조 및 생식세포의 미세구조는 종 특이성, 생식생태 및 계통에 따라 다르다. 일반적으로 이매패류의 정자는 각 분류군에 따라 핵과 첨체의 모양, 첨체의 axial rod, 미토콘드리아 수, 편모의 수 및 형태 등에서 다양한 특징을 보인다 (Morse and Zardus, 1997). Anadara trapez 등이 속하는 돌조개과 (Arcidae) 패류들의 정자 두부는 난형이며, 첨채에 axial rod가 없고, 중편에 4개의 미토콘드리아를 가진다. (중략)

• Applied Microscopy
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• v.39 no.2
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• pp.89-99
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• 2009

To investigate the morphological characteristics of spermatozoa of the grey red-blacked vole (Clethrionomys rufocanus) belongings to the subfamily Cricetinae, subgenus Clethrionomys were examined by scanning and transmission electron microscopes. The sperm head of C. rufocanus was an ax or hatchet in shape with a curved single dorsal hook. The total length of C. regulus sperm was 95.8 ${\mu}m$. The length of sperm head was 7.8 ${\mu}m$, and the tail (88.0 ${\mu}m$) consisted of four major segments: the neck (1.0 ${\mu}m$), middle piece (22.0 ${\mu}m$), and principal piece plus end piece (65.0 ${\mu}m$), respectively. The segmented columns were about 10~12 in number. The number of gyres of mitochondria ranged from about 170 to 178. The post-nuclear cap occupied about a half of nucleus. The equatorial segment is located between the post-nuclear cap segment and acrosomal cap on the nuclear surface. Nos. 1, 5 and 6 of the outer dense fibers were larger than the others. A fibrous sheath and longitudinal column of the principal piece were in evidence, but the fibrous sheath was not seen at the end piece. In conclusion, the morphological structures of sperm head and tail may be useful information to patterning of sperm evolution and classifying of species.

• Applied Microscopy
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• v.31 no.3
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• pp.223-233
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• 2001

The spermiogenesis of a Korean octopus, Octopus minor, inhabiting western of Korea Sea was observed by electron microscopy . The obtained results are as follows: The spermiogenesis of Octopus miner proceeds through four stages; early- , mid- , and late-spermatid, and mature sperm. An early spermatid is a spherical cell looking light due to the low electron density. The acrosome formed from Golgi complex of the upper nucleus looks dark due to the high electron density. The extra-nuclear rod (enr) stemming from proximal centriole is transformed from round shape into oval shape, elongating to the upper nucleus. In our observation, the axoneme was being formed from distal centriole, and the manchette composed of a number of microtubules is also found around nuclear membrane. In a mid-spermatid, chromatins in the nucleus contract shaping fine threads, and the manchette is also observed around nuclear membrane. Especially, the spherical acrosome is transformed into long oval one which is tinged with a number of horizontal stripes and has the middle electron density. In a late-spermatid, chromatins in the nucleus contract thick and short. Furthermore, the mitochondrial sleeve, in which the axoneme is surrounded with mitochondria, is observed at middle piece. The axoneme has a typical structure of 9+2 and around it, 9 coarse fibers are observed. Also in the acrosome cavity of mature sperm, horizontal striation is found. However, regularly spaced processes are peculiarly observed in there. A sperm is about 390 fm long, whose head is bent a little like a banana while the acrosome region is helical. In the middle piece of sperm, $11\sim12$ mitochondria are surrounding coarse fibers that reach the main piece of tail, while nothing but 9+2 structured axoneme is found in the end piece.

• Korean Journal of Poultry Science
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• v.16 no.2
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• pp.91-100
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• 1989

This study was conducted to observe 1) the changes of cellular association in seminiferous tubles from 2 to 8 weeks of age, and 2) the cycle phenomena of seminiferous epithelia at 14 weeks of age in Japanese quail. Total 80 birds were examined at a week interval from 2 to 8 weeks, and 14 weeks of age. The results were summarized as follows： 1) The body and testis weights showed most prominent increase during 4 to 5 weeks and 6 to 8 weeks of age respectively. And also the diameters of seminiferous tubles were abruptly enlaged during 6 to 8 weeks of age. 2) Genocytes in the seminiferous tubles were still in existence at 3 weeks of age, however they did not come out after 4 weeks of age. Spermatogonia, primary spermatocytes and spermatids made their first arpearances in the seminiferous from 3, 4 and 6 weeks of age, respectively. Spermatozoa were observed for the first time at 7 weeks of age, but full spermatogenic activity was completed from 8 weeks of age. 3) At 14 weeks of age, the average weight at testis was 3.7g and its ratio to the body weight was approximately 3.0 percent. And at this age, average diameter of seminiferous tubules was 192.08 $\mu\textrm{m}$, and average numbers of spermatogonia, spermatocytes, spermatids and spermatozoa within the cross section of seminiferous tubules were 7.74, 40.81, 28.42, 104.55 and 105.98, respectively. Spermatogonia and spermatid were classfied into 2 and 3 types, respectively. 4) At 14 weeks of age, the cycle of seminiferous epithelium could be divided into S stages with following characteristics. (1) Stage I： Seminiferous tubules showing type I and II spermatids. (2) Stage II： Seminiferous tubules showing type III spermatids only. (3) Stage III： Immature spermatozoa gathered near the sertoli cytoplasm. (4) Stage IV： Forming a bundle of 15-20 spematozoa. (5) Stage V： Spermatozoa bundle leaving the sertoli cytoplasm into lumen of the seminferous tubule. 5) Usually 2-3 stages of the seminiferous epithelium cycle were concurrently appeared within a tubular cross section, and frequency of each stage from I to V within cross section of seminiferous tubules were 11.91%, 27.03%, 27.96%, 19.04% and 17.98%, respectively.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.3
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• pp.56-64
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• 2021

Pavilion is an important landscape installation in the traditional landscaping and a representative facility that organizes space. To interpret and succeed the traditional landscape space, researches on the shape and structure of the traditional pavilion are also needed. However, researches on the style and structure of the traditional pavilion are difficult to be found. Accordingly this study aimed to identify the structural characteristics of roof part that occupied the largest portion in determining the shape of pavilion. Our research findings are as follows. As a result of analyzing 15 traditional Single-room square pavilions whose structure could be identified, it was found that the main building elements that distinguished the type of roof part in the Single-room square were crossbeam, ridge pole, and baluster. Depending on the presence of roofing members, pavilion was classified into five types: crossbeam, crossbeam+ridge pole, crossbeam+baluster, ridge pole, and baluster. In addition, as a result of analyzing the load and joint that worked on crossbeam based on the shape classification of roof part, it was found that in the traditional Single-room square pavilion, crossbeam was designed to play a balancing role between pillar and load. This study is significant in that it attempted to make a close interpretation of the shape of roof part in the pavilion and the role and function of building elements in terms of size, ratio, and load.

• Applied Microscopy
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• v.31 no.3
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• pp.245-256
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• 2001

The morphological characteristics of spermatogenic cells during the spermiogenesis of Paradoxornis webbiana were studied by transmission electron microscope. Spermiogenesis of P. webbiana was divided into ten phase. The chromatin granules became fibrous granules at the Golgi phase, gradually condensed at the cap phases, condensed as a stick at the acrosomal phase, and finally, a perfect nucleus was formed at the maturation phase. The formation of sperm tail began at the early Golgi phase, and completed at the late maturation phase. In particular, the dense materials existed in the sperm neck, which is wedged between the tip of segmented columns and the first mitochondria of the middle piece. The axone in the neck were surrounded by the dense materials. The axonema in spermatozoon contains a 9+2 arrangement of microtubules: 9 doublets, and 2 central single microtubules. Mitochondrial bundles of middle piece were composed of a pair of arms, which surrounded the axone of the middle piece by the $15^{\circ}$ angled-helical structure. The outer membrane of mitochondria were surrounded by microtubules in plasma membrane of the sperm. The undulating membrane had a helical structure, and the sperm plasma membrane was surrounded by undulating membrane.

• Korean Journal of Ichthyology
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• v.8 no.2
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• pp.74-83
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• 1996

The ultrastructure of the spermatozoa of the family Cobitidae, 6 genera and 12 species, was examinated under electron microscopes. Spermatozoa of the observed species consist of a head(nucleus), a short midpiece, and a single tai1(flagellum). It is of anacrosomal aquasperm type, lacking an acrosome. However, the spermatozoa of Nemacheilus toni has vestigal acrosome or acrosome-like vesicle in the anterior region of the nucleus during spermiogenesis, The nucleus of Cobitidae is approximately spherical except that N. toni is conic. The mid piece was under $3.0{\mu}m$ in length and contained 5-8 ring-shaped mitochodria. Genera Cobitis, Iksookimia, Niwaella, and Nemacheilus. have shorter midpiece, whereas Misgurnus and Lefua have longer midpiece. The flagellum was uniflagellate consisting of a typical 9+2 axoneme without fins.

• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.274-280
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• 2014

The spermatozoa of Platichthys stellatus is relatively simple cells composed of a spherical head, a short midpiece, and a tail, as in most Pleuronectiformes. The ultrastructure is characterized by the following features: a round nucleus with a deep nuclear fossa, the centriolar complex located at a right angle to each other, a short midpiece, a tail with paired lateral ribbon and no acrosome. However there are some minor morphological differences, including the appearance and number of the mitochondria, the shape and size of the nuclear fossa and the structure of the basal body. Especially the basal body structure consisting of a basal foot, a rootlet and nine alar sheets structures varies considerably in different species. It can be used as indicator of relationships in Pleuronectiformes because minute morphological differences might have functional and evolutionary significance. In conclusion, the spermatozoa of P. stellatus show a certain structural homogeneity and provide support for the concept that ultrastructural features of spermatozoa can be useful in taxonomic studies of Pleuronectiformes.