• Asian-Australasian Journal of Animal Sciences
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• v.8 no.2
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• pp.119-122
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• 1995

A total of 6 tamaraws were observed for determining coat color and measured for body conformation. Banding pattern of 4 blood proteins and 2 isozymes were analysed from the peripheral blood of two tamaraws. The coat colour of younger tamaraws were observed to be brown and adult was found to be complete black. The body weight, body length, withers height, head length, head width, horn length and tail length of adult male and female tamaraws were: 236 kg and 208 kg; 113.5 cm and 112.5 cm; 19.5 cm and 20 cm; 30.0 cm and 28.5 cm and 36.0 cm and 35.5 cm, respectively. The electrophoretic banding pattern, distance migrated and the allelic frequencies obtained in tamaraws were similar compared with that reported in swamp buffaloes. Although the sample size was very small, results of this study could be an important source of informations based on which a breeding programme can be designed to exploit some of the economic characters of tamaraw.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.725-730
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• 2015

We observed yellow catfish Pelteobagrus fulvidraco fingerlings cultured in land ponds in Korea swimming in a corkscrew spiral pattern while hanging head-up and tail-down at the water surface, before eventually dying. Externally, these fish displayed “hole in the head” disease, pale gills, and hemorrhages in the base of the pectoral and caudal fins; internally they had liver hemorrhages and kidney discoloration. The bacterium Edwardsiella ictaluri (YCK-01 and YCL-01) was identified in the kidneys and livers of diseased fish via phenotypic characteristics and PCR analysis using the ictaluri-specific primers IVS (an intervening sequence) and IRS (the inter-ribosomal spacer). Infectivity challenges by intraperitoneal and immersion routes showed that a representative bacterial strain (YCK) exhibited strong virulence to yellow catfish, with an LD₅₀ of 3.2×10⁴ CFU/fish and 2.5×10⁶ CFU/mL, respectively. This is the first report of E. ictaluri infection in yellow catfish from Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.157-162
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• 2003

Ultrastructure of germ cell during gametogenesis of surf clam, Spisula sachalinensis were investigated by electron microscopic observations. Oogonia are oval in shape and 5-6 ${\mu}m$ in diameter. They contain a large nucleus and have several mitochondria in the cytoplasm. Vitellogenic oocytes grew attached by a stalk to the germinal epithelium in the ovarian sac and their cytoplasm contained many yolk granules, lipid granules and mitochondria. Mature oocytes measuring 50-60 ${\mu}m$ in diameter have a nucleus containing an electron dense nucleolus, and a lots of yolk granules, lipid granules, mitochondria, rough endoplasmic reticulum and cortical granules were present in the cytoplasm. The surface of the plasma membrane in mature oocytes was formed of microvilli approximately 1.5 ${\mu}m$ long and enveloped in the vitelline layer. Spematogonia are oval in shape and about 5 ${\mu}m$ in diameter. Sprmatogonia develop into spermatocyte, spermatid and spermatozoon. The spermatozoon consisted of the head, midpiece and tail. The sperm head with diameter of about 1.5 ${\mu}m$ was ovoid, and contained the nucleus which consisted of acrosome. The four mitochondria encircled the centrosome in midpiece. The flagellum measuring about 40 ${\mu}m$ long had the classical 9+2 axoneme structure.

• Applied Microscopy
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• v.40 no.4
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• pp.253-259
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• 2010

The ultrastructure of sperms in testes of the pond smelt (Hypomesus nipponensis) was investigated using electron microscopes. The whitish testis was located between swim bladder and intestine. Especially, the left testis was larger than the right testis. The sperm was approximately $26\;{\mu}m$ in length. The sperm had an oval head and the acrosome was not found. The nucleus was about 400 nm in diameter and chromatin was incompletely condensed. The nuclear fossa deeply formed in sperm head and two centrioles were located in the fossa. The mitochondrium was observed only one in midpiece of the sperm and a motile flagellum consisted of an axoneme with a typical 9+2 pattern of microtubule. Also, the tail of the sperm has axonemal fins.

• Journal of Sericultural and Entomological Science
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• v.5
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• pp.39-42
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• 1965

The newly hatched silkworm can not come out with the head ahead, but on the contray, it comes out with the tail ahead when it comes out of the chorion, in case the loose-formed eggs are vibrated artificially, at the end of the incubation. So the newly hatched silkworm can not throw off the chorion alone which covers his head. This kind of eggs occurs about 30% when they are vibrated. In case they were raised, they could not grow well and some of them died. The result was quite bad. In conclusion, it would be better to distribute earlier the loose-formed eggs farmers and the loose-formed eggs must not be vibrated at the end of the incubation.

• Applied Microscopy
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• v.44 no.1
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• pp.1-7
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• 2014

The spermatogenesis of Siamese fighting fish, Betta splendens, belongs to Osphronemidae was investigated by light and electron microscopic observations. In primary spermatocyte stage, the nucleus was comparatively large ellipsoidal, and mitochondria showed a marked development in cytoplasm. In secondary spermatocyte stage, the germ cells were smaller than that of primary spermatocytes. The nucleus was a spherical shape and intercellular space was formed between germ cells. In spermatid stage, the early spermatids were not much different from a secondary spermatocyte. But, the chromatin condensation was occurred from the outside to the inside. The nucleus was more condensed. Intracellular space was larger than early spermatid. The mitochondria were rearranged in a middle piece, and occupied about half of the head part in early sperm. In sperm stage, the head of mature sperm was a spherical shape and had no acrosome. The flagellum was showed the typical 9+2 array of microtubules. Also, the tail of sperm had no lateral fins and outer coarse fibers. These ultrastructural characteristics can be used in classification of species.

• Journal of Aquaculture
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• v.12 no.1
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• pp.57-62
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• 1999

Experiments were performed to study the activity and fertility of grey mullet (Mugil cephalus) sperm after the courses of cold storage and cryopreservation. The head of spermatozoon showing spherical shape was sized $1.26{\pm}0.08 \{mu}textrm{m}$ in diameter and its nucleus contained numerous granular chromatins. Flagellum of tail showed typical 9＋2 structure. Preservation of grey mullet sperm was the most effective when it was stored with serum of the same species at $0^{\circ}C$ and sperm activity index was similar in egg-tris, 0.1 M, 0.3 M and 0.5 M glucose. When grey mullet sperm were cryopreserved in MFRS as diluent with 10% dimethyl sulfoxide was effective compared with other diluents. Some of post-thawed spermatozoa showed the enlarged head and ruptured plasma membrane compared with unfrozen spermatozoa.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.2
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• pp.105-115
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• 2008

Men's outer wear, such as jackets and coats appeared since the 16th century. They have been changed from doublets, coats, justaucorps, tail-coats, frock coats and morning coats to contemporary men's suits. Since the early 17th century, sleeve patterns of men's outer jackets had been mostly two-pieces close fitted patterns. The purpose of this article is to compare sleeve patterns of various jackets, which appear in various historic costume books. Armhole measurements, sleeve head measurements, amounts of ease, armhole depths, armhole widths, crown heights, sleeve width and sleeve angle had been compared to find out the differences among patterns of different times and styles. Coming to the present, the difference between top sleeve and under sleeve became more obvious, and the sleeve angle became less curvy. Another interesting point is that there had been considerable amounts of ease, which is the difference between sleeve head measurements and corresponding armhole measurements. It is because the sleeve has been attached to the armhole not by seam but by string. It is believed that the present sleeves have more natural curve and shape compared to the past.

• Wind and Structures
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• v.32 no.5
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• pp.487-499
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• 2021

The wind-blown sand effect on the high-speed train is investigated. Unsteady RANS equation and the SST k-ω turbulent model coupled with the discrete phase model (DPM) are utilized to simulate the two-phase of air-sand. Sand impact force is calculated based on the Hertzian impact theory. The different cases, including various wind velocity, train speed, sand particle diameter, were simulated. The train's flow field characteristics and the sand impact force were analyzed. The results show that the sand environment makes the pressure increase under different wind velocity and train speed situations. Sand impact force increases with the increasing train speed and sand particle diameter under the same particle mass flow rate. The train aerodynamic force connected with sand impact force when the train running in the wind-sand environment were compared with the aerodynamic force when the train running in the pure wind environment. The results show that the head car longitudinal force increase with wind speed increasing. When the crosswind speed is larger than 35m/s, the effect of the wind- sand environment on the train increases obviously. The longitudinal force of head car increases 23% and lateral force of tail increases 12% comparing to the pure wind environment. The sand concentration in air is the most important factor which influences the sand impact force on the train.

• Journal of Embryo Transfer
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• v.31 no.2
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• pp.109-116
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• 2016

The recovery of epididymal sperm in animals is considered as one of the important tools to preserve high value or endangered species. However, there are no appropriate castrating indicators such as months of age in bull, sperm morphology, and motility, particularly in young Korean native bull (Hanwoo). Therefore, this study aimed to investigate sperm number, morphology, and motility of sperm in the epididymis tail of young Hanwoo bulls at 8 and 15 months of age. After castration, epididymal tails were collected and minced with blades to recover sperm. In experiments 1 and 2, sperm number, morphology, and motility were examined. Total number of sperm and percentage of normal sperm from bulls at 8 months of age was lower than that of bulls at 15 months of age after collection (P<0.05). Percentage of abnormal head, tail, proximal cytoplasmic droplet, dead and damaged acrosome of sperm from bulls at 8 months of age were higher than those of bulls at 15 months of age (P<0.05). In experiment 3, sperm motility from bulls at 8 and 15 months of age were examined before freezing and after thawing. Frozen-thawed sperm at 8 months of age showed low total motility and motile sperm with ${\geq}25{\mu}m/sec$ compared to those at 15 months of age and commercially-used sperm (P<0.05). In conclusion, sperm derived from the epididymal tail of bulls at 8 months of age showed high abnormal morphology and poor motility, which are not adequate for AI and IVF. On the other hand, sperm derived from the epididymal tail of bulls at 15 months of age showed high normal morphology and motility.