• Ecology and Resilient Infrastructure
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• v.11 no.1
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• pp.11-22
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• 2024

A fishway is an artificial waterway or device used to resolve difficulties in the movement of fish in a river. Most existing fishways are made of concrete and emit toxic substances, which has a negative impact on the river environment. Accordingly, there is a need to develop fishway construction technology that is eco-friendly and can increase movement efficiency. The technology presented in this study is an integrated porous structure that combines the aggregate with a biopolymer material extracted from castor oil, a non-toxic material. It is a fishway construction technology using eco-friendly materials that can allow vegetation to grow on the surface. In this study, an eco-friendly fishway mixed with biopolymer and aggregate was built on a real scale and the fish movement efficiency was tested and analyzed. As a result of the experiment, a total of 201 fish of 14 species were released with tags inserted, and the detection rate of released fish was confirmed to be 82.6% on average. A total of 40 fish of 6 species were transported upstream through the fishway, and the average passage rate was confirmed to be 21.7%. As a result of checking the circadian migration pattern, it was found that all fish mainly migrate during the day. It was confirmed that there was no significant functional difference between a fishway using biopolymer and a concrete fishway. It is believed that a fishway using biopolymer can be used as a replacement for a concrete fishway.

• Fisheries and Aquatic Sciences
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• v.11 no.4
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• pp.205-208
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• 2008

The mixotrophic dinoflagellate Cochlodinium polykrikoides was reported to be linked to major fish kills in Korea and Japan since the 1990s. Rapid and sensitive detection of microalgae has been problematic because morphological identification of dinoflagellates requires light microscopic and scanning electron microscopic observations that are time consuming and laborious compared to real-time PCR. To address this issue, a real-time PCR probe targeting the ITS2 rRNA gene was used for rapid detection and quantification of C. polykrikoides. PCR inhibitors in water column samples were removed by dilution of template DNA for elimination of false-negative reactions. A strong association between cell quantification using real-time PCR and microscopic counts suggests that the real-time PCR assay is an alternative method for cell estimation of C. polykrikoides in environment samples.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.595-598
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• 2000

Aeromonas hydrophila is a pathogen to fish as well as human. It is a food-borne disease, and causes severe mortality in fish, and sometimes severe septicemia in human. In this study, a rapid detection method using latex agglutination has been developed for A. hydrophila. Polyclonal antibodies were raised against membrane and whole cells of three isolates from rainbow trout. Among these, latex particles coated with antibodies raised against whole cells of isolate No. 2 showed the best sensitivity. With latex particles coated with this antibody, we could detect $5{\times}10^4$ CFU of A. hydrophila in 5 min. The cross-reactivity with bacteria constituting the normal intestinal microflora and other pathogens for rainbow trout was insignificant. This latex agglutination assay method produced positive reaction with all clinical isolates of A. hydrophila which were identified by species-specific PCR for 16S rRNA in A. hydrophila.

• Journal of fish pathology
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• v.31 no.1
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• pp.49-55
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• 2018

Tendency of viral hemorrhagic septicemia virus (VHSV) detection from 2001 to 2016 in Korea was studied based on 15 reported cases. Since the VHSV was first detected from cultured olive flounder (Paralichthys olivaceus) in Pohang in 2001, it has been continuously reported from olive flounder farms in various regions of the Korean coastal area. So far, the virus has been detected from 2 farmed fishes, 12 wild marine fishes and 2 marine bivalves. All the 67 isolates were belong to VHSV genotype IVa. The predisposing factor analysis from different olive flounder farms revealed that the VHSV were highly detected from the juveniles under 40 g in body weight, in the temperature range from 9.5 to $17^{\circ}C$ and during the period of March to June. Therefore, we recommend that farmers, need to exercise caution against VHSV infection in Spring.

• The Journal of the Korea Contents Association
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• v.8 no.1
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• pp.308-317
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• 2008

The objects real time rendered in the 3D cyber space can interact with each others according to the events which are happened when satisfying some conditions. But to representing the behaviors with these interactions, too many event conditions are considered because each behavior pattern and event must be corresponded in a one-to-one ratio. It leads to problems which increase the system complexity. So, in this paper, we try to physical method based on elasticity force for representing more realistic behaviors of AI fish and apply to the deformable multi-detection sensor, so we suggest the new method which can create the various behavior patterns responding to one evasion event.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.100-103
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• 1998

A survey on the incidence of metacercariae infection of Clonorchis sinensis in the fresh water fish, Pseudorasbora parva which is well known as the second intermediate host for this fluke was carried out in the upper stream of Phoung-tack stream, Kyungki province during the period of October to November 1997. Forty fish in P. parva were collected by netting, or using the bait in transparent bowls from the two different districts located in Osung-myun, Phoungtack-gun and transported to the laboratory. The body length and weight were measured. They were from 5.0 to 7.6 cm in length and 1.0 to 5.0 g in weight. A total of 40 P. parva were divided 3 groups by the size (70-79, 60-69 and 50-59 mm) and were digested by artificial digestion with pepsin-Hcl solution in a 36$\circ$C incubator and then examined the infection density of metacercariae of the fresh water fish under a binocular dissecting microscope. The incidence of metacercariae infection in P. parva was 406 of 40 examined and the metacercariae detection rate showed 77.5%. The average number of metacercariae detected in P. parva was 10.2. The results of the survey indicate that Clonorchis sinensis infection may occur by consuming raw fresh water fish caught from the upper stream of Phoungtackho, Kyungki province.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.187-191
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• 1998

Chemotherapy can not be applied for the control of fish viral diseases because viruses depend on host machinery for their replication. Although new control strategies including vaccination are under development, avoidance of virus introduction by rapid and correct diagnosis is the best way of fish viral disease control. Although observation of virus particles with an electron microscope is an easy method for virus detection, it take a few days for the sample preparation. In order to shorten the sample preparation time, microwave radiation was applied in the procedure. With this method, 15 seconds was enough for fixation of virus infected fish samples or cultured cells inoculated with infectious hematopoietic necrosis virus, which takes 2-4 hours with routine methods. Also four minutes was enough for polymerization of embedding resin which takes 24-48 hours with routine methods. Samples prepared with microwave were good enough for direct electron microscopic observation and immunogold labeling assay.

• Journal of fish pathology
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• v.31 no.1
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• pp.1-8
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• 2018

Causative agent of infectious hematopoietic necrosis (IHN) belonging to genus Novirhabdovirus (Rhabdoviridae). Economic losses caused by IHNV are serious in mainly Oncorhynchus spp. including rainbow trout O. mykiss and Atrantic salmon Salmo salar. IHNV was initially found by endemic presence in U.S. West Coast for sockeye salmon fry O. nerka and chinook salmon fry O. tshawytscha in the 1950s, and it has spread to Japan, Korea and Taiwan in the 1970s, and also to Italy and France in the 1990s. Currently, IHNV is detectable in many parts of the world, including Russia and South America. Mortality due to IHNV infection in fish with ${\leq}0.5g$ of body weight reaches 60% to 100%, while the mortality reduces by fish growing. In recent years, onset of IHNV infection has increased also in fish with large sizes. Here, we introduce molecular epidemiology and virulence changes of IHNV in East Asia, furthermore, we discuss on future prospects in IHNV researches.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.1
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• pp.46-52
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• 2013

After an outbreak of viral disease in an aquafarm, release of virus (es) from infected fish into environmental seawater has been suspected. In the present study, we utilized a negatively charged membrane (HA type) as an efficient method for concentration and detection of fish pathogenic viruses, specifically, megalocytivirus and viral hemorrhagic septicemia virus (VHSV) present in field-collected seawater samples or inoculated into seawater artificially. Positively charged viruses adsorbed onto the negatively charged membrane and were eluted with 1 mM NaOH (pH 10.5) following rinsing with 0.5 mM $H_2SO_4$ (pH 3.0). Megalocytivirus and VHSV particles isolated using anegatively charged HA membrane from seawater inoculated with each virus at a concentration of 10 viral particles/mL were of sufficient quantity to show positive results in atwo-step PCR (or RT two-step PCR); however, despite it being negatively charged, a cellulose acetate (CA) membraneshowed negative results. In quantitative PCR, the detection limits of the HA membrane for megalocytivirus and VHSV in seawater were 1.20E+00 viral particles/mL and 1.22E+01 viralparticles/mL, respectively. The calculated mean recovery yields from 1 L seawater spiked with known concentrations of megalocytivirus and VHSV particles were 28.11% and 23.00%, respectively. The concentrate of a 1-L sample of culturing seawater from the aquatank of flounder suffering from VHSV showed clear positive results in PCR when isolated with an HA, but not a CA, membrane. Thus, viral isolation using an HA membrane is a practical and reliable method for detection of fish pathogenic viruses in seawater.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.329-337
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• 2012

Considerable attention has been given to the accuracy of HER-2 testing and the correlation between the results of different testing methods. This interest reflects the growing importance of HER-2 status in the management of patients with breast cancer. In this study the detection of HER-2 gene and centromere 17 status was evaluated using dual-colour primed in situ labelling (PRINS) in comparison with fluorescence in situ hybridization (FISH). These two methods were evaluated on a series of 27 formalin fixed paraffin embedded breast carcinoma tumours, previously tested for protein overexpression by HercepTest (grouped into Hercep 1+/0, 2+ and 3+). HER-2 gene amplification (ratio${\geq}2.2$) by PRINS was found in 3:3, 6:21 and 0:3 in IHC 3+, 2+ and 1+/0 cases, respectively. Comparing FISH and IHC (immunohistochemistry), showed the same results as for PRINS and IHC. Chromosome 17 aneusomy was found in 10 of 21 IHC 2+ cases (47.6%), of which 1 (10%) showed hypodisomy (chromosome 17 copy number per cell${\leq}1.75$), 7 (70%) showed low polysomy (chromosome 17 copy number per cell=2.26 - 3.75) and 2 (20%) showed high polysomy (chromosome 17 copy number per cell ${\geq}3.76$). The overall concordance of detection of HER-2 gene amplification by FISH and PRINS was 100% (27:27). Furthermore, both the level of HER-2 amplification and copy number of CEN17 analysis results correlated well between the two methods. In conclusion, PRINS is a reliable, reproducible technique and in our opinion can be used as an additional test to determine HER-2 status in breast tumours.