• Fisheries and Aquatic Sciences
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• v.23 no.6
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• pp.15.1-15.14
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• 2020

Background: Large rivers are ecological treasures with high human value, but most have experienced decades of degradation from industrial and municipal sewage, row-crop agricultural practices, and hydrologic alteration. We reviewed published analyses of long-term fish diversity publications from three intensively managed large river ecosystems to demonstrate the conservation potential of large river ecosystems. Results: We show how the incorporation of recent advances in river concepts will allow a better understanding of river ecosystem functioning and conservation. Lastly, we focus on the Wabash River ecosystem based on high conservation value and provide a list of actions to maintain and support the ecosystem. In the Wabash River, there were originally 66 species of freshwater mussels, but now only 30 species with reproducing populations remain. Although there were multiple stressors over the last century, the largest change in Wabash River fish biodiversity was associated with rapid increases in municipal nutrient loading and invasive bigheaded carps. Conclusions: Like similarly neglected large river systems worldwide, the Wabash River has a surprising amount of ecological resilience and recovery. For instance, of the 151 native fish species found in the 1800s, only three species have experienced local extinctions, making the modern assemblage more intact than many comparable rivers in the Mississippi River basin. However, not all the changes are positive or support the idea of recovery. Primary production underpins the productivity of these ecosystems, and the Wabash River phytoplankton assemblages shifted from high-quality green algae in the 1970s to lower less nutritional blue-green algae as nutrient and invasive species have recently increased. Our recommendations for the Wabash River and other altered rivers include the restoration of natural hydrology for the mainstem and tributaries, nutrient reductions, mechanisms to restore historical hydrologic patterns, additional sediment controls, and improved local hydraulics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.239-246
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• 2003

We have examined the 16S-23S rRNA intergenic spacer region (ISR) of Vibrio vulnificus KCTC 2959. ISRs were amplified by primers complementary to conserved regions of 16S and 23S rRNA genes. ISR amplicons were cloned and sequenced. Analysis of the ISR sequences showed that V. vulnificus KCTC 2959 contains five types of polymorphic ISRs. Size of ISRs ranged from 424 to 741 bp in length and the number of tRNA genes ranged from one to four. The ISRs were designated as ISR-E $(tRNA^{Glu}),\;ISR-IA\;(tRNA^{Ile}-tRNA^{Ala})$, ISR-EKV $(tRNA^{Glu}-tRNA^{Lys}-tRNA^{Val})$, ISR-IAV $(tRNA^{Ile}-tRNA^{Ala}-tRNA^{val})$ and ISR-EKAV $(tRNA^{Glu}-tRNA^{Lys}-tRNA^{Ala}-tRNA^{Val})$ based on their tRNA genes. Multiple alignment of representative sequences from different Vibrio species revealed several domains of high sequence variability. We used the sequences of variable domains to design species-specific primer for detection PCR. Specificity of the primers was examined using genomic DNA prepared from 18 different Vibrio species. The results showed that the PCR using primers designed in this study can be used to detect V. vulnificus from other Vibrio species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.230-236
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• 1987

The correlation between tintinnid and dinoflagellate by means of seasonal variation of standing crops was investigated at two selected stations in Masan Bay, well-known as a red tide zone in southern coastal waters of Korea, during the period from January 1981 to December 1982. The most dominant dinoflagellates mainly belonged to $20-60\;{\mu}m$ of size class, and Gymnodinium and Prorocentrum were predominant from spring to summer season. Of tintinnid, Favella spp. were most dominant and associated with dinoflagellate blooms at the same season. Especially, Favella spp. were most positively correlated with $40-60\;{\mu}m$ size class of dinoflagellate, and also represented higher multiple corrleation with outer station (St.2), comprising relatively large species of Gymonodinium and Protogonyaulax, than with inner station (St. 1), dominated by Prorocentrum blooms. Thus, the interspecific food selection by size and morphology between tintinnid including Favella and dinoflagellate is recognized and it is considered to be an important factor influenecing on the prey-predator relationship in lower trophic level in the surveyed area.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.2
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• pp.147-155
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• 2008

The purpose of this study was to identify the causal relationship developmental activity of the marine sports among the educational value and barrier's factors in a middle school teachers in Busan. Responses were collected from 352 questionnaires which participated in the survey chosen by convenient sampling from the middle school teachers who working the area of Busan. A total of 338 responses were used in data analysis; 14 questionnaires were excluded form data analysis because of incomplete or missing data. To conduct this study the multiple regression analysis was used by SPSS 10.0. The result of this study disclosed; first, The factors of educational value such as self-concept development, collaboration, human relationship, and emotional development were statistically causal relationship with the developmental activity of the marine sports. The other factors of creativity, leisure activity, and health were not statistically causal relationship with the development activity of the marine sports. Second, the barrier's factors of facility and weather were statistically causal relationship with the developmental activity of the marine sports. The other barrier's factors of safety accident, program, and participation expense were not statistically causal relationship with the developmental activity of the marine sports.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.3
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• pp.780-789
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• 2016

This study was conducted to clarify a correlation among science-related attitude, overexcitability and parents' rearing attitude perceived by elementary school students. For this purpose, questionnaire surveys were carried out for 276 elementary school students consisted of 5th and 6th grades. The results were as follows. First, science-related attitude, overexcitability, and parents' rearing attitude perceived by elementary school students were meaningfully different on gender. boys'average was higher in science-related attitude than girls'. In the case of overexcitability, boys'average was higher in psychomotor and intellectual overexcitability than girls', while girls'average was higher in emotional and sensual overexcitability than boys'. According to the analysis for parents' rearing attitude perceived by elementary school students, girl students perceived that their parents more firmly controlled them as compared with boy students. Second, according to the results conducting t-test for types of parents' rearing attitude perceived by students, boy students' average was meaningfully higher in the types of love-autonomy than girl students'. There was no difference between the groups of love-autonomy type and hostility-autonomy type. Third, there showed a meaningful correlation between students' science-related attitude and parents' rearing attitude in order of love, hostility, autonomy, and control type. There showed a meaningful correlation between students' science-related attitude and intellectual, sensual, imaginational, psychomotor, and emotional overexcitability in order. Last, according to multiple regression analysis, factors effecting on science-related attitudes were intellectual overexcitability, love among the types of parents' rearing attitude perceived by students im order.

• 한국해양학회지
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• v.29 no.4
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• pp.392-401
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• 1994

We examined the temporal characteristics of the oceanic eddy diffusion at 5 coastal regions of Korea by measuring the separation distances of multiple drifters released simultaneously at the same by the GPS and Decca transponder system. The observed variance of separation distance, for the time scales from minutes to hours, is proportional to t/SUP m/ with scaling exponent m between 1.2 and 2.0. The observed Lagrangian trajectories of drifters show fractal characteristics instead of random walk or Brown motion. As an effort toward a development of a realistic model of the oceanic eddy diffusion, we simulated the Lagrangian trajectories of drifters by fractional Brown motion (FBM) model. The observed variances of drifter separations can be generated by the FBM process provided the Hurst exponent is the same as the observed one. We further showed that the observed power law in the variance of drifter separations cannot be simulated with an ordinary Brown motion or random walk process.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.1
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• pp.31-36
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• 2011

This study developed a normal temperature-circulatable retort-sterilized crab analog (RSCA) with a long shelf-life by retort sterilization. We examined the optimum sterilization conditions and quality characteristics of the RSCA. A central composite design for response surface methodology (RSM) was adopted to optimize of the retort sterilization. The central composite design consisted of 11 samples: four factorial points, four star points, and three central points. The sterilization temperature and $F_0$-value for retort sterilization were the independent variables, and the shearing force, whiteness, and sensory score for texture were the dependent variable. The RSM analysis of the multiple response optimization for the RSCA using the Minitap statistical programing gave an $F_0$-value of 3.3 min. at $117.5^{\circ}C$. The RSM analysis also indicated that the sterilization temperature during retort sterilization was the most influential factor, while the $F_0$-value had little effect on the quality of the RSCA. The moisture, pH and volatile basic nitrogen contents of the RSCA product were 73.1%, 7.3 and 17.2 mg/100 g, respectively, and viable cells count was >18 CFU/g. And sensory quality characteristics of this RSCA was similar to those of a commercial crab analog.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.197-206
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• 2011

This study was conducted to optimize processing of functional seasoning sauce for instant noodles (SSIN) using response surface methodology (RSM), and to compare the functional properties of commercial SSIN. Central composite designs were adopted in the SSIN processing for ingredient formula optimization. Concentrations of sea tangle ($X_1$), traditional soy sauce ($X_2$), yeast extract ($X_3$) and Ecklonia cava extract (ECE) ($X_4$) were chosen as independent variables. The dependent variables were glutamic acid content ($Y_1$), score of sensory evaluation ($Y_2$), and antioxidative activity ($Y_3$). We found the optimal conditions to be $X_1$=3.91%, $X_2$=20.57%, $X_3$=3.04% and $X_4$=3.78%. The predicted values of the multiple response optimal conditions were $Y_1$=124.0 mg/100 g, $Y_2$=7.6 and $Y_3$=1.95. The antioxidative activity (PF, PF=oil induction period with sauce/oil induction period with distilled water) and ACE inhibitory activity of ECE-added SSIN were 1.98 and 29.0%, respectively, which were significantly higher than those of commercial SSIN (1.09 and 4.4%, respectively).

• Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.471-478
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• 2014

Genomic organization, including the structural characteristics of 5'-flanking regions of two 65-kDa protein (WAP65) isoform genes associated with warm temperature acclimation, were characterized and their transcriptional responses to immune challenges were examined in the intestine, kidney and spleen of the mud loach (Misgurnus mizolepis; Cypriniformes). Both mud loach Wap65 isoform genes displayed a 10-exon structure that is common to most teleostean Wap65 genes. The two mud loach Wap65 isoforms were predicted to possess various stress- and immune-related transcription factor binding sites in their regulatory regions; however, the predicted motif profiles differed between the two isoforms, and the inflammation-related transcription factor binding motifs, such as NF-${\kappa}B$ and CREBP sites, were more highlighted in the Wap65-2 isoform than the Wap65-1 isoform. The results of qRT-PCR indicated that experimental immune challenges using Edwardsiella tarda, lipopolysaccharide or polyI:C induced the Wap65-2 isoform more than Wap65-1 isoform, although modulation patterns in response to these challenges were tissue- and stimulant-dependent. This study confirms that functional diversification between the two mud loach Wap65 isoforms (i.e., closer involvement of Wap65-2 in the acute phase of inflammation and innate immunity) occurs at the mRNA level in multiple tissues, and suggests that such differential modulation patterns between the two isoforms are related to the different transcription factor binding profiles in their regulatory regions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.1
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• pp.25-32
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• 2000

A combination steering system was designed to provide the flexibility in controlling the steering wheel in fishing operations of the inshore and coastal fishing vessels. The designed steering system basically is consisted of three driving units, such as a electrically driven hydraulic pump unit with a solenoid control valve, a DC motor driven hydraulic pump unit and a manually driven hydraulic pump unit, and two controllers to provide remote steering on the deck, respectively. The steering torque was measured and analyzed to investigate the dynamic performance of the developed steering system. The steering system showed excellent linearity between the working pressure of cylinder and the torque of rudder post in case of increasing in rudder angle from $5^{\circ} to 35^{\circ}$ that is, the steering torque increased from $10.4 kgf{\cdot}m$ to $105.3 kgf{\cdot}m$ and then the working pressure of cylinder fluctuated from 6.3 kgf/cm super(2) to 16.4 kgf/cm super(2). The steering time of 3.2 sec in remote hydraulic steering by the on/off solenoid valve control was much faster than 13.2 sec in the manual steering by the helmsman and 11.6 sec in the electric steering by a DC motor, and then it was verified that operation of one unit does not affect other units in combination steering system in any way. Furthermore, the developed steering system can be remotely controlled in multiple stations of the deck during the fishing operation and the automatic pilot steering unit can be used to add hydraulic steering.