• Title/Summary/Keyword: Multiple fisheries

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Effects of abiotic stressors on kelp early life-history stages

  • Lind, Alyssa C.;Konar, Brenda
    • ALGAE
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    • v.32 no.3
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    • pp.223-233
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    • 2017
  • Kelp forests and the many vital ecosystem services they provide are threatened as the severity of climate change and other anthropogenic stressors continues to mount. Particularly in the North Pacific, sea surface temperature is warming and glacial melt is decreasing salinity. This study explored the resiliency of early life-history stages of these foundation species through a factorial laboratory experiment. The effects of rising sea surface temperature under low salinity conditions on kelp spore settlement and initial gametophyte growth in Eualaria fistulosa, Nereocystis luetkeana, and Saccharina latissima were investigated. Decreased settlement and growth were observed in these species at elevated temperatures and at low salinity. Eualaria fistulosa spores and gametophytes were the most negatively impacted, compared to the more widely distributed N. luetkeana and S. latissima. These results suggest that N. luetkeana and S. latissima could potentially outperform E. fistulosa under projected conditions. However, despite decreased performance among all species, our findings indicate that these species are largely resilient to temperature changes when exposed to a low salinity, even when the temperature changes are immediate and extreme. By exploring how early life-history stages of several key kelp species are impacted by dual stressors, this research enhances our understanding of how kelp forests will respond to projected and extreme changes in temperature when already stressed by low salinity.

A Cyan Fluorescent Protein Gene (cfp)-Transgenic Marine Medaka Oryzias dancena with Potential Ornamental Applications

  • Vu, Nguyen Thanh;Cho, Young Sun;Lee, Sang Yoon;Kim, Dong Soo;Nam, Yoon Kwon
    • Fisheries and Aquatic Sciences
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    • v.17 no.4
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    • pp.479-486
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    • 2014
  • To evaluate their potential utility as an ornamental organism, novel transgenic marine medaka Oryzias dancena strains with a highly vivid fluorescent phenotype were established through transgenesis of a cyan fluorescent protein gene (cfp) driven by the endogenous fast skeletal myosin light chain 2 gene (mlc2f) promoter. The transgenic marine medaka strains possessed multiple copies of transgene integrants and passed their fluorescent transgenes successfully to subsequent generations. Transgenic expression in skeletal muscles at both the mRNA and phenotypic levels was, overall, dependent upon transgene copy numbers. In the external phenotype, an authentic fluorescent color was dominant in the skeletal muscles of the transgenic fish and clearly visible to the unaided eye. The phenotypic fluorescent color presented differentially in response to different light-irradiation sources; the transgenics displayed a yellow-green color under normal daylight or white room light conditions, a strong green-glowing fluorescence under ultraviolet light, and a cyan-like fluorescence under blue light from a light-emitting diode.

Comparative Analysis of the Growth for Selectively Bred Korean Turbot Scophthalmus maximus Population (한국 육종터봇(Scophthalmus maximus)의 성장률 비교 분석)

  • Kim, Min Sung;Kim, Tae Hwan;Han, Jae Yong;Jo, Hyeon Kyeong;Kwak, Ju Ri;Park, Ji Been;Suh, Jong-pyo;Lee, Woo-jai
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.53 no.4
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    • pp.563-565
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    • 2020
  • Turbot Scophthalmus maximus can be cultured at a higher density and has a faster growth rate than olive flounder Paralichthys olivaceus, making it an attractive alternative for flounder farmers in Korea. As it is a relatively new species to Korean farming environments, there is no general farming protocol, which takes multiple generations to develop, for turbot in Korea. Nevertheless, we applied breeding technology to develop a stock, which we considered first-generation turbot. Then we compared its growth rate (an important economic trait) to different populations (the original stock of Korean turbot, French turbot, and Chinese turbot). The four different populations were grown in similar culture conditions. First-generation Korean turbots grew about 28% faster than all others. We will continue to select for important traits such as color, disease resistance, and heat tolerance in this turbot broodstock; we believe that with the appropriate selection process, Korean turbot should become competitive in the markets, and will become a major farming species in the Korean aquaculture industry.

Meiobenthic Communities in Extreme Deep-sea Environment (심해 극한 환경에서의 중형저서동물 군집)

  • Kim Dong-Sung;Min Won-Gi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.39 no.spc1
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    • pp.203-213
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    • 2006
  • The spatial patterns of meiobenthic communities in deep-sea sediment were examined. Sediment samples for analyzing of meiobenthic community structure were collected using a remote operated vehicle (ROV), multiple corer TV grab at 20 stations at five sites. In all, 15 meiofauna groups were recorded. Nematodes were the most abundant taxon. Benthic foraminiferans, harpacticoid copepods, polychaetes, and crustacean naupii were also dominant groups at all sites. The total meiofauna density at the study sites varied from 49 to 419 ind./$10cm^2$. The maximum density was recorded at a site located in Challenger Deep in the Mariana trench where simple benthic foraminifera with organic walls flourish. These distinctive taxa seem to be characteristic of the deepest ocean depths. Active hydrothermal sediments contain up to 150 harpacticoid copepods per $10cm^2$ of sediment. In a inactive ridge sediments, devoid of macrofaunal organisms:, the abundance of harpacticoid copepods never exceeded 15 ind./$10cm^2$. Multivariate analysis (multidimensional scaling) revealed significant differences in community structure among the three regions; near an active hydrothermal vent, in the deepest ocean depths and at typical deep-sea bed sites.

Construction of Chimeric Human Epidermal Growth Factor Containing Short Collagen-Binding Domain Moieties for Use as a Wound Tissue Healing Agent

  • Kim, Dong-Gyun;Kim, Eun-Young;Kim, Yu-Ri;Kong, In-Soo
    • Journal of Microbiology and Biotechnology
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    • v.25 no.1
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    • pp.119-126
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    • 2015
  • Among the various human growth factors, epidermal growth factor (hEGF, consisting of 53 amino acids) has various effects on cell regeneration, stimulation of proliferation, migration of keratinocytes, formation of granulation tissues, and stimulation of fibroblast motility, which are important for wound healing. Owing to their multiple activities, EGFs are used as pharmaceutical and cosmetic agents. However, their low productivity, limited target specificity, and short half-life inhibit their application as therapeutic agents. To overcome these obstacles, we fused the collagen-binding domain (CBD) of Vibrio mimicus metalloprotease to EGF protein. About 18 or 12 amino acids (aa) (of the 33 total amino acids), which were essential for collagen-binding activity, were combined with the N- and C-termini of EGF. We constructed, expressed, and purified EGF (53 aa)-CBD (18 aa), EGF (53 aa)-CBD (12 aa), CBD (18 aa)-EGF (53 aa), and CBD (12 aa)-EGF (53 aa). These purified recombinant proteins increased the numbers of cells in treated specimens compared with non-treated specimens and control hEGF samples. The collagen-binding activities were also evaluated. Furthermore, CBD-hybridized hEGF induced phosphorylation of the EGF receptor. These results suggested that these fusion proteins could be applicable as small therapeutic agents in wound tissue healing.

Molecular Identification of a Sea Anemone (Cnidaria: Anthozoa: Actiniaria) Obtained in Gijang, Busan (부산 기장에서 채집된 말미잘의 분자생물학적 방법을 이용한 동정)

  • Yoo, Sang Joon;Kim, Do-Hyung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.50 no.4
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    • pp.447-452
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    • 2017
  • In this study, we tried to identify a sea anemone collected from the coast of Gijang, Busan. The anemone was morphologically similar to species belonging to the genus Anthopleura, but its morphological characteristics did not allow for confirmed identification to species level. Multiple genes from mitochondrial cytochrome oxidase III, 12S and 16S rRNA, and nuclear 18S and 28S rRNA, were amplified for multilocus sequence typing (MLST) analysis using genomic DNA extracted from the sampled anemone and a different primer set. Based on the MLST analysis, the anemone obtained in this study was identified as Anthopleura artemisia. Also, the sequence of internal transcribed spacer-2 was most closely related to A. artemisia, indicating that this single region might be useful for anemone identification. This study shows significance of molecular identification for sea anemones, and will be helpful in studies of sea anemone identification using genotyping-by-sequencing.

Reproductive ecology of the glowbelly, Acropoma japonicum (Perciformes: Acropomatidae) in the coastal waters off Gori, Korea (고리 주변 해역에 출현하는 반딧불게르치 (Acropoma japonicum)의 생식생태)

  • Baeck, Gun-Wook;Huh, Sun-Hoi;Park, Joo-Myun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.48 no.2
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    • pp.118-127
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    • 2012
  • The reproductive ecology of the glowbelly, $Acropoma$ $japonicum$ was examined using 637 specimens collected monthly from January to December 2006 in the coastal waters off Gori, Korea. The specimens ranged in standard length (cm, SL) from 2.9 to 11.4cm for female, 2.7 to 10.5cm for male. The gonadosomatic index (GSI) of female was highest in September and decreased until December, and the spawning season lasted from August to November. The monthly sex was not different significantly ($x^2$-test, p>0.05). The size at 50% maturity was estimated at 6.0cm SL. $A.$ $japonicum$ was multiple spawner that spawn on more than one occasion in a single spawning season, and the maximum egg diameter was 0.75mm. Fecundity (F) ranged from 12,052 to 104,246 eggs, with the mean of 38,321 eggs. The relationships between fecundity and standard length (cm, SL), body weight (g, BW) were estimated as $F=86.278SL^{2.9652}$ ($R^2$=0.7970) and $F=3036BW^{1.0081}$ ($R^2$=0.7992), respectively.

Suggestions for Improvement of Performance Assessment according to Achievement Evaluation (성취평가 시행에 따른 수행평가 내실화 방안)

  • Won, Hyo-Heon
    • Journal of Fisheries and Marine Sciences Education
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    • v.26 no.1
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    • pp.203-213
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    • 2014
  • The purpose of this study was to search for the ideal role and performance assessment(PA) in the current school system of Korea, and then to propose some suggestions to improve PA, based on the previous research. The result of the study is presented below. The direction of PA application in school was made to follow the theoretical meaning of PA, to solve the problems related ti its adoption in school, and to help teachers educate students more effectively. The main goal of PA application in term of 'school education' is to help students learn more effectively. That is, the assessment is not only for the evaluation, but also for improving students' learning. PA can be used to assess students' strength and weakness in terms of their academic achievement of various fields of the subject. Also, PA can be used to assess students' academic achievement as an alternative method to the multiple-choice test. Finaly, the results of this study propose some suggestions about how to conduct PA in school to the stakeholders such as educational authorities, schools, teachers, students and parents.

Characterization and expression profiles of aquaporins (AQPs) 1a and 3a in mud loach Misgurnus mizolepis after experimental challenges

  • Lee, Sang Yoon;Nam, Yoon Kwon;Kim, Yi Kyung
    • Fisheries and Aquatic Sciences
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    • v.20 no.9
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    • pp.23.1-23.9
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    • 2017
  • Two distinct cDNAs encoding aquaporins (mmAQPs 1a and 3a) were isolated and characterized from mud loach Misgurnus mizolepis. The identified mud loach AQP cDNAs encode for polypeptides of 260 and 302 amino acids. Topology predictions confirmed six putative membrane-spanning domains connected by five loops and the N- and C-terminal domains being cytoplasmic. The mud loach AQPs 1a and 3a showed broad distribution in multiple tissues including immune-responsive tissues as well as osmoregulatory tissues. Hence, the diversity of AQP distribution and expression possibly indicated its differential functions in the regulation of fluid movement in response to environmental stimuli. The transcription of mmAQP genes was differentially modulated by immune challenges. In particular, the mmAQP3a expression level in the liver was more responsive to immune challenges than that of mmAQP1a. Taken together, fish stimulation or infection resulted in significant modulation of mud loach AQP genes, suggesting potential functional roles of these proteins in piscine pathophysiological process.

Influences of Children's Perception of Ego-resilience and Family Strength on School Life Satisfaction According to Their Family Structure (가족구조에 따른 아동의 자아탄력성 및 가족건강성이 학교생활만족도에 미치는 영향)

  • Lee, Jeong-Oun;Lee, Kyeong-Hwa
    • Journal of Fisheries and Marine Sciences Education
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    • v.22 no.4
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    • pp.621-632
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    • 2010
  • The purpose of this study was to investigate the relationships of ego-resilience, family strength, and school life satisfaction according to their family structure. 303 cases of them were selected from 912 elementary students' data in Busan and analyzed using the independent-samples t-test, Pearson's coefficient of correlation, and multiple regression. The results of the study were as follows: First, it was shown that children of parents family had positive perception on the ego-resilience, family strength, and satisfaction with school life than children of nontraditional family. Second, in children with parents family, family strength is a more powerful predictor of satisfaction with school life than ego-resilience. Finally, in children with nontraditional family, ego-resilience is a more powerful predictor of satisfaction with school life than family strength. The results implicated that ego-resilience and family strength of children influence on their school life satisfaction differently according to their family structure and therefore it needed for family structure-based mediation program to improve children' school life.