• The Journal of Korea Robotics Society
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• v.9 no.1
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• pp.57-66
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• 2014

This paper describes the design concept of a bio-inspired legged underwater and estimating its performance by implementing simulations. Especially the leg structure of an underwater organism, diving beetles, is fully adopted to our designing to employ its efficiency for swimming. To make it possible for the robot to both walk and swim, the transformable kinematic model according to applications of the leg is proposed. To aid in the robot development and estimate swimming performance of the robot in advance, an underwater simulator has been constructed and an approximated model based on the developing robot was set up in the simulation. Furthermore, previous work that we have done, the swimming locomotion produced by a swimming patten generator based on the control parameters, is briefly mentioned in the paper and adopted to the simulation for extensive studies such as path planning and control techniques. Through the results, we established the strategy of leg joints which make the robot swim in the three dimensional space to reach effective controls.

• Journal of fish pathology
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• v.21 no.2
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• pp.139-148
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• 2008

Vertebral deformity in hatchery-reared black sea bream (Acanthoparus schlegelii) fingerlings occurred. Deformed fish had a good appetite but no clinical signs were found except the vertebral abnormality and darkness around the dorsal skin of the deformed vertebra. As more than 90% of the hatchery-reared fish exhibited vertebral abnormality, the fingerlings could not be used for commercial seeds any more. No morphological change in the swim bladder was observed. Histopathological changes on the deformed vertebra, gill, liver, and spleen were observed to clarify the cause of the deformity. The vertebra were irregularly deformed upward with the shape of "V" in an alphabetic character causing the spinal cord and dorsal aorta suppressed. The diameters of the muscle fibers around the deformed vertebra, especially, in the dorsal part, were much smaller and more irregular than those in normal fish, and the gabs between the fiber bundles were enlarged. No evidence of inflammatory responses in the lateral musculature were found. On the basis of normal inflation of the swim bladder, cultural environments for growth of the fingerlings, and histopathological alterations in the muscle, vertebra and gills, it is suggested that high speed of water current in the culturing aquaria between 23 to 30 days after hatching was responsible for the development of vertebral abnormality.

• Korean Journal of Ichthyology
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• v.5 no.1
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• pp.53-67
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• 1993

In December of 1989 and 1990, matured adults of chum salmon were collected from Namdae-chun River in Yangyang-gun, Kangwon-do, Korea. Artificial insemination was made at captured locations. The fertilized eggs were hatched in trough incubators and the larvae were reared in laboratories of the Yangyang Fisheries Institute and the Korea Ocean Research and Development Institute. The fertilized eggs of this species were demersal and separated, and red in color with mean diameter of 7.2mm. The hatching took place from 480 to 531 degree($^{\circ}C$) days after fertilization. The newly hatched alevins were 1.80 to 2.56cm in total length with big yolk and lied on the bottom. In 35 days after hatching, the alevin attained $3.56{\pm}0.12cm$ in total length, and absorbed the yolk completely to become fry with 7 to 11 parr marks on the body. In 3 months after hatching, and the fries became smolt with silvery scales haring 5.67-6.53cm in total length. The early larval developments of chum salmon could be divided into three stages according to the changes in body shapes and length : larval stage before swim up, swim up stage and smolt stage. The growth of snout, trunk and body height to total length were faster than other body parts in swim up stage.

• Journal of Nutrition and Health
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• v.28 no.5
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• pp.375-386
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• 1995

This study was designed to investigate the changes in energy substrates, glucose and non-esterified fatty acid(NEFA), and fatty acid compositions in serum, following physiolgical stress in rats fed diets containing various fatty acids. Forty two Sprague-Dawley strain male rats, weighing 108$\pm$2.1g, were fed 3 different experimental diets for 4 weeks. The diets were composed of 105 fat(w/w) of either corn oil(CO;18:2 n6:57%), plant perilla oil(PO;18:3 n3:59%), or tuna fish oil(FO;20:5 n3:17%%, 22:6 n3:19%). After 4 weeks of feeding, each group wa subdiveided into (a) control, (b) 2 min swim in ice-cold water. Animals wer decapitated 20min after commencing the swim; trunk blood, brain, liver and epididymal fat pad were obtained. The levels of serum corticosterone, glucose, NEFA, triglyceride, fatty acid compositions, brain serotonin and 5-hydroxyindoleacetic acid were determined. Basal levels of corticosterone na NEFA of serum were significantly lower in fish oil fed animals than those of any other oil fed animals. Compared to either perilla oil-fed or corn oil-fed rats, cold swim stress in fish oil fed rats produced significantly smaller NEFA and larger corticosterone responses. However, there was no significant difference in basal levels of serum glucose. Stress increased serum glucose levels slightly, and the amount of increment was larger in fish oil rats than those of any other oil fed rats than those of any other oil fed rats, although all the values were normal level. Dietary fats and stress did not affect serotonin metabolism. In additions, the composition of fatty acids in serum was significantly affected by the dietary compostion of fatty acids and stress. Stress induced decreases in monounsaturated fatty acid and non-polyunsaturated fatty acid concentration in either perilla oil fed or fish group, but did not in corn oil fed group. Stress resulted in changes in fatty acid metabolism similar to that associated with essential fatty acid(EFA) dificiency, when feeding animals n-3 fatty acids in diet. In conclusion, feeding fish oil was more effective to decrease NEFA in serum than feeding perilla oil or corn oil and improved lipid metabolism, when the rats were maintained in normal or exposed to stressful environment. However, the fact that feeding diet containing n-3 fatty acids decreased EFA status under stress suggests that the requirement of n-6 PUFA should be increased in these groups.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.289-292
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• 2007

This research focuses on the relationship between participation characteristics on exercise needs of swimming participants. To this end, our research efforts questioned adult swimmers with increasing partner, time, determined factor of participation evinced higher levels of exercise needs. The research targeted the current(2006) membership of an aquatic facility operating in the Busan Gwangyeok-Shi, both male and female were selected as 299 participants of the study. This research utilized a exercise needs survey developed by Byung Gi Lee's team(1989). The data was analyzed through Reliability, Frequency and the ANOVA method. The results of this study are as follows: First, Those who regularly swim with a partners and those who swim alone showed differences in their exhibitionist tendency levels. Second, Those who scheduled their swimming activities in the evenings showed more motivation to exercise than those who swim in the mornings or afternoons. Third, Determining factors in beginning an aquatic exercise routine were quality of facilities or instructors, and these participants showed a different level of desire to reduce stress and exhibitionist tendency levels.

• Journal of Embryo Transfer
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• v.15 no.1
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• pp.67-75
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• 2000

This study was conducted to establish the optimal conditions for in vitro embryo production using oocytes derived from follicles of slaughter-house ovaries. The ovaries of Hanwoo were obtained from a local slaughter-house. The oocytes were aspirated from visible follicles of 2~7mm in diameter. The recovered oocytes which were completely surrounded by at least 2 layers of cumulus cells and a homogeneous cytoplasmic pigmentation were used. The selected oocytes were washed 3 or 4 times with D-PBS containing 10% bovine calf serum (BCS) and matured in vitor (IVM) in Ham's F-10 supplemented with 10% BCS or 0.01 $\mu\textrm{g}$/ml epidermal growth factor(EGF) at 39$^{\circ}C$ under 5% CO2 in air for 24 hours. They were fertilizqed in vitro (IVF) with fresh sperm separated by Percoll density gradient or swim-up in TALP media. The zygotes were cultrued with or without bovine oviductal epitherial cells(BOEC) in media(HECM-6 supplemented with 11 amino acid and / or TCM-199 supplemented with 10% BCS) for 7 to 10 days. The results obtained were as follow: The cleavage rate and developmental rate to blastocyst after maturation and IVF were not significantly different between Ham's F-10 with EGF(76.0% vs. 44.0%) and BCS(75.9% vs. 43.6%)(P<0.05). The cleavage rate and development rate to blastocyst after fertilizing by swim-up or Percoll method were not signifciantly(P<0.05) different between swim-up (80.2% vs. 29.2%) and Percoll(81.9% vs. 26.5%) (P<0.05). The cleavage rate in TCM 199(80.5) was signficiantly higher than that in HECM-6 (72.0%) (P<0.05). However, developmental rate to blastocyst using TCM 199 following HECM-6 for 3 or 4 days (42.2%) was significantly higher than that in TCM-199 alone(26.7%)(P<0.05). The cleavage rate and development rate of embryos produced in vitro by exchange timing for HECM-6 media were not significantly different between in day 3(78.6% vs. 45.5%) and day 4(75.0% vs. 43.2%)(P<0.05). The cleavage rate and developmental rate to blastocysts according to co-culture system were not significantly different between with (74.2% vs. 41.4%) and without BOEC(73.95 vs. 43.5%) (P<0.05). The number of blastomere in blastocyst stage after co-culture with or without BOEC was not significantly different (106.7$\pm$5.1 and 96.6$\pm$4.0). In conclusion, the most transferable IVP embryos could be produced from Ham's F-10 medium for IVM, Percoll density gradient method for IVF sperm separation and in vitro culture in HECM-6 until day 3 or day 4, and then transferred into TCM-199 until day 9 within adequate embryo density in culture droplets after insemination.

• Journal of Life Science
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• v.21 no.4
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• pp.542-548
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• 2011

Food-dependent exercise-induced anaphylaxis (FDEIA) is a distinct form of food allergy induced by physical exercise. It is typified by the onset of anaphylaxis during exercise, which is preceded by the ingestion of causal food allergens. Diagnosis of FDEIA is heavily dependent on clinical history. To describe the physiopathological mechanism, etiologic factors, and clinical manifestations, we evaluated the spleen index, proliferation assay of lymphocyte, ROS, ASAS, and cytokines levels in sensitized and exercise-trained mice. One-hundred mice were bred in the animal lab at D and P university under controlled conditions [$22{\pm}2^{\circ}C$, RH 45-55%, and a 12-hour photoperiod]. Animals are 7-weeks-old at the time of study and were fed a standard commercial chow diet from 09:00 to 15:00 over the 8-week study period. The mice were allowed access to distilled deionized water ad libitum. Daily food intake and weekly body gains were routinely recorded throughout the experimental period using computing scale (CAS). Mice were divided into the control group (S; control sensitized, n=25), 30 min swim training group (S30, N=25), 50 min swim training group (S50, N=25), and 80 min swim training group (S80, N=25). The results were as follows: Spleen index showed the highest level in the S80 group compared to other groups; this level was exercise-dependent. In proliferation assay of Med and OVA, the S80 group showed the highest level compared to the other groups; this level also was exercise intensity- dependent. Peritoneal ROS and IL-4 showed a statistically significant difference compared to S; however, there was no significant differences in ROS among S30, 50, and 80. From the results, we concluded that FDEIA is correlated with exercise intensity based on the levels of peritoneal ROS and cytokine profiles.

• Korean Journal of Ichthyology
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• v.33 no.1
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• pp.8-14
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• 2021

Spawning behavior of the endangered Korean fish, Microphysogobio koreensis, was investigated in the Seomjingang (river), Imsil-gun, South Korea, during the spawning season, April to May 2012. The mating system of M. koreensis, a broadcast spawner, was a primitive spawning mode, and involved one male and one female, unlike group spawning fishes. Spawning behavior of M. koreensis in the wild were observed in eight patterns as resting, male chase, body beating, parallel swim, female withdrawal, male competition, spawning and not guard while spawning behavior in the glass tank were verified in six patterns as resting, male chase, body beating, parallel swim, spawning and not guard. In particular, a behavioral attempt of the pre-spawning stage showed more frequently in the wild than in the glass tank. We assume that difference of spawning behavior might be implication on behavioral restrictions in small and narrow indoor glass tank.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.110-110
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• 2003

• Journal of Oriental Neuropsychiatry
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• v.24 no.3
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• pp.271-280
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• 2013

Objectives : The development of natural drugs with antidepressant effects is important and needed. This study was performed to investigate the antidepressant-like effects of the distilled water extract of Portulaca oleracea L. (POL) in a mouse model and to investigate the role of ${\alpha}$-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptors in producing these antidepressant-like effects. Methods : The forced swim test (FST) and tail suspension test (TST) were used to investigate the behavioral anti-depressive-like effects of POL in mice. Additional behavioral experiments with 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo[f]quinoxaline-2,3-dione, an AMPA receptor antagonist, were undertaken to determine the involvement of the antidepressant-like properties of POL in AMPA receptor throughput. Results : Oral administration of the POL extract (100 mg/kg) 1 h prior to testing significantly reduced the immobility times in the FST and TST. The antidepressant-like effects of the POL extract were not increased in a dose-dependent manner. Pre-treatment with NBQX significantly attenuated the reduction in immobility time induced by the POL extract in the FST. Conclusions : The distilled water extract of POL has antidepressant-like effects, which may be related to AMPA receptor. Pre-treatment with NBQX significantly attenuates the reduction in immobility time induced by the POL extract in the FST.