• Journal of Environmental Science International
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• v.26 no.6
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• pp.779-788
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• 2017

In this study, we analyzed the changes in the echolocation and prey-capture behavior of the horseshoe bat Rhinolophus ferrumequinum from search phase to capture time. The experiment was conducted in an indoor free-flight room fitted with an ultra-high-speed camera. We found that the bats searched for food while hanging from a structure, and capturing was carried out using the flight membrane. In addition, it was confirmed that the mouth and uropatagium were continuously used in tandem during the capturing process. Furthermore, using Constant Frequency (CF), we confirmed that the prey catching method reflected the wing morphology and echolocation pattern of R. ferrumequinum. The echolocation analysis revealed that the pulse duration, pulse interval, peak frequency, start-FM-bandwidth, and CF duration decreased as the search phase approached the terminal phase. Detailed analysis of echolocation pulse showed that the end-FM bandwidth, which increases as it gets nearer to the capture time of prey, was closely related to the accurate grasp of the location of an insect. At the final moment of prey capture, the passive listening that stopped the divergence of the echolocation was identified; this was determined to be the process of minimizing the interruption from the echo of the echolocation call emitted from the bat itself and sound waves emitted from the prey.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.263-269
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• 2023

This study aims to contribute to the research on resource recovery for the rapidly declining population of Liparis tanakae by observing the larval development process and the morphology of juveniles based on their growth. Natural spawning eggs collected in Yeosu were used for observing the process of egg development and larval morphology. The water temperature during the rearing process was maintained at 12.3~13.5℃ (average 12.7℃). The fertilized eggs had an egg diameter ranging from 1.57 to 1.79 mm (average 1.71 mm) and were spherical and adhesive. Within 4 hours 35 minutes after fertilization, they reached the two-cell stage, and after 74 hours 10 minutes, the formation of the yolk sac began. At 106 hours post-fertilization, a caudal fin appeared at the tail tip. Hatching began at 526 hours, and the larvae developed with the yolk sac positioned just behind the eyes. The newly hatched larvae had both the mouth and anus open. Melanophores appeared inside the lower jaw and around the tail on the third day after hatching. By the 16th day after hatching, most of the yolk was absorbed, and melanophores were visible in the head region. Finally, on the 63rd day after hatching, the head region significantly developed, and the body shape and mouth were similar to those of an adult fish, signifying the transition to the juvenile stage. This study will serve as valuable data for aquaculture techniques related to the conservation and restoration of fish species based on the hatching and juvenile morphology of Liparis tanakae.

• Animal cells and systems
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• v.12 no.2
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• pp.101-108
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• 2008

Recently, Platypus koryoensis has been reported as a major pest of oak trees in Korea which can introduce the pathogenic fungus(Raffaelea sp.) by making galleries into the heartwood of the tree. As the beetle has developed its effective drilling mouthpart enough to make tunnels, we have analyzed the fine structural aspects of the mouthpart using the field emission scanning electron microscopy(FESEM) to reveal its mechano-dynamic characteristics. The mouthparts of this ambrosia beetle which consist of a labrum, a pair of mandibles, a pair of maxillae and the labium exhibit typical morphology of mycophagous coleopteran beetles and have those characteristics of chewing mouthparts that can excavate galleries in the hardwood. Both of maxillary and labial palpi have the functions of direct the food to the mouth and hold it while the mandibles chew the food. The distal ends of these palpi are flattened and have shovel-like setae. Females have larger maxillary palpi and a larger gular region than males in general.

• The korean journal of orthodontics
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• v.23 no.3 s.42
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• pp.427-445
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• 1993

The ankylosis of temporomandibular joint occured by several causes directly developes TM joint disfunction, In cases with prolonged condylar ankylosis, especially at growing age the condylar ankylosis evokes malfunction of growth center area, and then developes the abnormal facial morphology and malocclusion. Therefore it must be cured. Almost authors have agreed to the necessity of surgical correction of the TMJ anylosis. but they did not decide the one surgical method to get the best result. The Tx. method suggested by many authors are the using interposition after resection of condyle to remain a lever of 3rd class in Mn. kinetics, the autogenous condylar graft and the alloplastic condylar graft. Some authors have got the satisfied results only with the condylectomy of the involved TMJ. This study also operated only the detachment of fibrous adhesion on ankylosed condylar side and then established occlusion in the case with the unilateral TMJ ankylosis and fibrous joint adhesion and facial asymmetry evoked after the fracture of condylar head at early age. This study got a improved mouth opening and a stable postsurgical result after 1 year. Also, this study reviewed many author's study about the chanracteristics, etiology, diagnosis and Tx. method for the ankylosis of TMJ.

• Parasites, Hosts and Diseases
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• v.50 no.3
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• pp.263-267
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• 2012

The present study was performed to describe 2 human cases infected by the horsehair worm, Parachordodes sp., in Japan. Two gordiid worms were collected in the vomit and excreta of an 80-year-old woman in November 2009 in Kyoto city, and in the mouth of 1-year-old boy in December 2009 in Nara city, Japan, respectively. Both worms were males having bifurcated posterior ends and male gonads in cross sectional specimens. They were identified as Parachordodes sp. (Nematomorpha: Chordodidae) based on the characteristic morphologies of cross sections and areoles in the cuticle. DNA analysis on 18S rRNA partial sequence arrangements was also carried out and both worms were assumed to be close to the genus Paragordionus based on tree analysis, and far from Gordius sp. which has already been reported in humans in Japan. DNA sequencing of the Parachordodes worm does not appear on the database; therefore, more information on the gene sequences of the genus Parachordodes from humans, animals, or intermediates is required.

• Journal of Korean society of Dental Hygiene
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• v.2 no.2
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• pp.159-173
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• 2002

The 180 toothbrushes out of 18 models( ten brushes for each model) were used for this examination among the toothbrushes for adults which were sold in the domestic markets. After three-month brushings through a roll ing method and Bass method were practiced with Toothbrush Stroke Tester which reproduced brushing methods outside the mouth, I investigated the morphology bristle tips of using scanning electron microscope(SEM). The conclusions are as follows. 1. Soft bristle toothbrushes(of 8 models out of 9 models) were badly damaged at the bristles end after 3 month toothbrushing. 2. Medium bristle toothbrushes(of four models out of five models) were irregularly worn at the bristles end after 3 month toothbrushing. 3. Hard bristle toothbrushes(of three models out of four models) were chisel-shapedly worn at the bristles end after 3 month toothbrushing. 4. Taper-shaped toothbrushes were very irregularly bent at the bristles end after 3 month toothbrushing. 5. It was examined in the bristle stiffness that soft bristle toothbrushes were found in 9 models(50.00%), medium bristle toothbrushes in 5 models(27.78%), and hard-bristle toothbrushes in 4 models(22.22%).

• Development and Reproduction
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• v.19 no.1
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• pp.25-31
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• 2015

We have launched an investigation for Embryonic Development, Larvae and Juvenile Morphology, of Buenos aires tetra in order to build basic data of Characidae and fish seeding production. We brought 50 couples of Characidae from Bizidduck aquarium in Yeosu-si, Jeollanamdo, from Korea on March of 2015. We put them in the tetragonal glass aquarium ($50{\times}50{\times}30cm$). Breeding water temperature was $27.5{\sim}28.5^{\circ}C$ (mean $28.0{\pm}0.05^{\circ}C$) and being maintained. The shape of fertilized egg was round shape, and it was adhesive demersal egg. The egg size was 0.63~0.91 mm (mean $0.74{\pm}0.07mm$, n=20). After getting fertilized egg, the developmental stage was gastrula stage, and embryo covered almost two-thirds of Yolk. Incubation was happened after 16 hours 13 minutes from gastrula stage, and the tail of juvenile came out first with tearing egg capsule. Immediately after the incubation, prelarvae had 3.78~3.88 mm length (mean $3.84{\pm}0.04mm$, n=5), and it had no mouth and anus yet. 34 days after hatching from the incubation, juvenile had 8.63~13.1 mm (mean $10.9{\pm}1.66mm$), and it had similar silver-colored body shape with its mother.

• 한국해양학회지
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• v.19 no.1
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• pp.82-88
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• 1984

The Gwangyang Bay, southern coast of Korea, is characterized by its semi-enclosed basin morphology and mesotidal regime. The Seomjin River, in particular, has a complex delta depositional system at its mouth, which has approximately 44$\textrm{km}^2$ in the total surface area. Various sedimentary environments, such as delta, intertidal flat, subtidal zone and major tidal channels are recognized based on sediment facies and depositional regime. However, the essential intertidal flat environments are developed mainly in the western parts of the bay which is generally low in energy, i, e. tidal current and wave action.

• Development and Reproduction
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• v.18 no.4
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• pp.241-249
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• 2014

Hyphessobrycon eques is a famous fish for ornamental fish market and aquarium. They are inhabit in regions of Amazon and Paraguay River basin. Serpae fishs were investigated 2-3 males are chased to female, and then males attempted to simulate the females abdomen. After fertilization, eggs were kept in incubators at $28^{\circ}C$. The fertilized eggs had adhesive and demesal characteristics and had a mean diameter of $0.92{\pm}0.01mm$. Larvae hatched at 16 hrs post fertilization. The hatched larvae averaged $2.90{\pm}0.16mm$ in total length ($L_T$). Complete yolk sac resorption and mouth opening occurred on the third day post hatching. At 45 days post hatching, the larvae were $12.5{\pm}1.60mm$ $L_T$ and had reached the juvenile stage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.134-138
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• 1999

Eggs and larval development of Chelon affinis were reared and observed in the laboratory with parent fishes obtained in the Minrak fish market Pusan on March, 1997. The spawned eggs of the species are transparent, round, separated, floated, and their diameters were varied within 0.95$\~$1.06 mm. Hatching began about 73 hours after spawning at $16.0^{\circ}C$. The newly hatched larvae were 1.72$\~$1.92 mm in total length with 19 myomeres, mouth and unopened anus, rod shape melanophores distributed in body. The larvae absorbed yolk material completely in 5 days after hatching and became postlarvae.