• Journal of fish pathology
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• v.9 no.2
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• pp.177-183
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• 1996

A new RNA virus isolated from abnormally swimming behavior has caused mortalities in salmonid fish (Oh et al., 1995 a), A reverse transcriptase (RTase) activity of the virus was determined by using poly r(A) : oligo d(T) as templete : primer. This RTase activity was associated with virus particles of buoyant density of 1.16 g/ml. The virus particles in sucrose fractions were enveloped and were about 85 nm diameter with central electron-dense core. The brain and kidney samples of artificially infected fish showed RTase activity. Virus particle associated proteins about 120, 80, 65, 61, 48, 42, 35, 30, 25, 19, and 15 kDa were observed when examined by polyacrylamide gel electrophoresis analysis. This study showed the presence of a new retrovirus in salmonid fish, which tentatively called RVS (Retrovirus of salmonid).

• The Plant Pathology Journal
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• v.21 no.1
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• pp.83-85
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• 2005

Ditylenchus acris was isolated from diseased strawberry plants. Frequently, D. acris and Aphelenchoides fragariae occur together in a strawberry plant. Both species appeared very similar in the shape, length, swimming behavior and causing symptoms, and difficult to distinguish them by a stereomicroscope. But they were easily distinguished under a compound microscope especially by their tail shape, median bulb, vulva position, and bursa.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.3
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• pp.1-17
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• 2013

Objectives: In this research, the effect of samul-tanggahyangbuja on depression and learning in ovariectomized rats subjected to repetitive stress were assessed. Samul-tanggahyangbuja is the prescription consisting of Samul-tang and Cyperi Rhizoma. Methods: Ovariectomized rats were repeatedly stressed over a 2-week period. After being orally medicated with samul-tanggahyangbuja (100 or 400 mg/kg), rats performed the Morris water maze test and forced swimming test, and social exploration was assessed in a behavior test. As well, sucrose intake was measured and measurements of blood serum corticosterone and the change of interleukin-$1{\beta}$ (IL-$1{\beta}$) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in blood samples were made. Results: 1. In the Morris water maze test, rats medicated with 100 mg samul-tanggahyangbuja mastered the maze in a shorter time on the 4th day in comparison with the control group, while rats medicated with 400 mg samul-tanggahyangbuja mastered the maze more quickly (p<0.05 on the 3rd day ; p<0.01 on the 4th day, as compared to control). 2. Immobility time in the forced swimming test was significantly decreased in rats receiving 400 mg samul-tanggahyangbuja compared with the control group (p<0.05). 3. Sucrose intake and active social behavior of rats receiving 400 mg samul-tanggahyangbuja were markedly increased in comparison with the control group (p<0.01). 4. Blood serum corticosterone measurements revealed decreased blood serum corticosterone level after medicating with samul-tanggahyangbuja. But it was not statistically significant. 5. Treatment with either dose of samul-tanggahyangbuja significantly reduced IL-$1{\beta}$ and TNF-${\alpha}$ (p<0.05). Conclusions: These results suggest that samul-tanggahyangbuja possesses the anti-depressant and cognitive-enhancing activities related to menopause.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.4
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• pp.435-446
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• 2014

Tidal turbulence was examined using three-dimensional tidal velocity data observed at a trench offshore of Tongyoung, Korea. The kinetic energy and intensity, including the variation period of the flow velocity and direction, were used to investigate the relationships between tidal turbulence and fishing gear dynamics, including the effects of swimming fish during fishing operations. As the resultant velocity increased from 0.2 to 0.9 m/s, the kinetic energy also significantly increased, while the turbulence intensity decreased from 50 to 10%. Tidal flow in strong flow fields displayed shorter periods of between 4 and 10 s, as determined by fast Fourier transform, the global wavelet method, and peak event analysis, and the periods were compared with the period of response to swimming fish and to oscillation of fishing gear. As mean velocity increased, velocity amplitude also increased from 0.1 to 0.6 m/s, and its directional amplitude changed markedly from 20 and $90^{\circ}$. Our study suggests that tidal turbulence can influence fish behavior or fishing gear geometry during fishing operations, although our analysis considered only a limited area. In future work, observations should be carried out over a more extensive depth and area.

• Korean Journal of Oriental Medicine
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• v.9 no.1
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• pp.157-178
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• 2003

Objective : This study was designed to assess the protective effects of Chengwhabosimtang on the animal model of depression, chronic mild stress(CMS). Method : Male Sprague-Dawley rats Were used for this experiment. The subjects Were divided into 3 groups (1. CMS-drug: Chengwhabosimtang administered during CMS treatment, 2. CMS-vehicle: water administered, 3. normal ). After 4 weeks of CMS treatment they were executed Forced swimming test(FST) and Elevated plus maze. Tyrosine hydroxylase(TH) in ventral tegmental area(VTA) and c-Fos in paraventricular nucleus(PVN) were measured. Result : 1. In FST, CMS-drug group showed significantly decreased immobility behavior. 2. CMS-drug group showed no significantly lower TH level in VTA than CMS-vehicle group. 3. CMS-drug group showed significantly less c-Fos expressed cell bodies in PVN than CMS-vehicle group. 4. In Elevated plus maze, CMS-drug group showed no significantly anxiety. Conclusion : These results suggest that Chengwhabosimtang may have protective antidepressant effects in CMS model rats. And these effects could be explained by the elevated stress-copying behaviors which are related with PVN of hypothalamus and dopaminergic neurons in VTA.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.3
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• pp.266-272
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• 2013

The objective of this study was to monitor and evaluate the schooling characteristics, including the distribution density (volume backscattering strength) and acoustic size (target strength), of commercially valuable species swimming in response to artificial reefs installed at Suyeong Man, Busan, Korea. Fish aggregations at two artificial reef areas and at a nearby natural rocky reef habitat were recorded and analyzed using a 70 kHz split-beam echo sounder and 330 kHz side-scan sonar from August to September, 2006. An underwater CCTV camera system was also used to observe marine organisms in physical contact with and swimming very close to artificial reefs. During the acoustic observations at three reef sites, useful information about schooling characteristics of fish aggregations responding to artificial reefs were obtained, but more trials are needed to confirm significant differences in schooling behavior and geographical distributions in areas containing natural reef structures and artificial reefs.

• Korean Journal of Medicinal Crop Science
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• v.22 no.3
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• pp.196-202
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• 2014

Depression is one of the most common neuropsychiatric disorders and has been associated with the neuroendocrine system and alterations in behavior. Schisandra chinensis Baillon is one of major medicinal plants used as a Korea medicine and food sources, and has been processed in the fields of various food products and medicinal herbs. The chronic mild stress (CMS) protocol is widely used to evoke depressive-like behaviors in laboratory mice or rat. The CMS procedure induced some behavioral changes that are compatible with the common expectations, i.e. 'anhedonic' behavior and can affect corticosterone level. The present study, Schisandra chinensis extract administration by daily gavage from the 3 weeks exhibited an antidepressant-like effect on CMS-induced depression in mice. Schisandra chinensis extract administration at dose of 200mg/kg significantly increased the sucrose consumption, and decreased the immobility durations in forced swim test and tail suspension test. Furthermore the corticosterone level decreased than control group. In conclusion, Schisandra chinensis extract showed antidepressant-like effects on sucrose preference test, forced swimming test and tail suspension test based on CMS model.

• Journal of Oriental Neuropsychiatry
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• v.15 no.1
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• pp.101-119
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• 2004

Ginseng Radix Alba and Cyperi Rhizoma were investigated for their anti-depressant effects. For this purpose, forced-swimming test, tail suspension test, hot plate test, reserpine-induced hypothermia, aggressive behavior test were performed. In addition, the brain content of 5-hydroxyindoleacetic acid(a metabolite of serotonin), the monoamine oxidase activity, anticonvulsant effect, sleep enhancement effect were determined. The results are as follows: In the forced swimming test, Ginseng Radix diminished the duration of immobility by 45.5% compared to the control group, while Cyperi Rhizoma showed weaker effect (12.4% reduction) at 2g/kg. In the tail suspension test, the effect of Ginseng Radix(43.7% reduction) are also better than that of Cyperi Rhizoma(15.6% reduction) at 2g/kg. In the hot plate test, Ginseng Radix showed no difference as compared to control, while Cyperi Rhizoma increased the jump latency time by about 25% after administration for 10 days. In the reserpine-induced hypothermia test, both drugs slowly dropped the body temperature compared to the control group, especially the rate of hypothermia of Ginseng Radix was 24.0% at 1g/kg. In the aggressive behavior test, both drugs delayed the onset time, decreased the duration and frequency, of which effects were better in Cyperi Rhizoma. The content of 5-hydroxyindoleacetic acid in mice brain was slightly increased in Ginseng Radix, while Cyperi Rhizoma increased its level almost to the control group. Both drugs inhibited the monoamine oxidase activity in a dose-dependent manner, but the effect(51.2%) of Cyperi Rhizoma was more potent than the effect(11.8%) of Ginseng Radix. In the pentobarbital-induced sleep test, Cyperi Rhizoma exhibited no significant difference against the control group, while Ginseng Radix showed about two-fold enhancement at 2g/kg. The anticonvulsant effect of both drugs delayed the onset time, shortened the duration of convulsion and diminished the lethality, but Ginseng Radix were better than Cyperi Rhizoma.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.193-201
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• 2006

We researched the reproductive ecology of pale chub, Zacco platypus that inhabits Gajeong-cheon and Wonju-cheon that are a tributary to the Han river. The nuptial organ was formed on the head part, the anal fin and the tail part in male, the change of nuptial color was outstanding. By their changing body shape, the anal fin was extended and body depth came to be high during the spawning season in both sexes. Territorial male of defending behavior were head butting, rotated fighting, parallel swimming, biting and expelling. After pale chub located himself from the upper of the female that was approached to the side parallelling with the female, male and female spawned digging sand with their anal fin by vibrating and any parental care of the eggs was not taken. The spawning interval and lasting time were relevant to individuals density of spawning ground.

• Journal of Practical Agriculture & Fisheries Research
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• v.23 no.1
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• pp.81-87
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• 2021

Olive flounders which were cultured in commercial fish farm showed abnormal swimming behavior in November 2020. Then, gradual mortality was observed in the fish farm. During the diagnosis, bacterial strain KNCFKW-PN1 was isolated from the kidney of the dead fish. Based on the sequence of gyrase B subunit gene, KNCFKW-PN1 was proved to be Pseudoalteromonas nigrifaciens, showing 99.59% nucleotide identity with that of P. nigrifaciens LMG 2227^T. According to the result of antibiotic susceptibility test, P. nigrifaciens KNCFKW-PN1 showed intermediate resistance to ciprofloxacin, and was resistant to ampicillin, cefepime, cefotaxime, ceftazidime, and amikacin. This is the first report of the isolation of multiple-antibiotic-resistant P. nigrifaciens from olive flounder.