• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.631-635
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• 1995

In order to develop effective manufacturing method and to improve quality of low-salt fermented squid(10% of table salt), we investigated the effects of temperature, salinity and pH on the growth of Staphylococcus xylosus, Micrococcus varians, Pseudomonas diminuta and Pseudomonas D2 isolated from of low-salt fermented squid and the growth characteristics of these bacteria during fermentation were elucidated. All bacteria showed good growth during the process of low-salt fermented squid(pH 6~7 ; concentration of NaCl, 7~10% ; temperature, 7~1$0^{\circ}C$) and their cell numbers increased as fermentation proceeded under the same fermentation condition.

• Journal of the korean society of oceanography
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• v.39 no.2
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• pp.119-135
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• 2004

A three-dimensional numerical model using POM (the Princeton Ocean Model) is established in order to understand the dispersion processes of the Yangtze River water in the Yellow and East China Seas. The circulation experiments for the seas are conducted first, and then on the bases of the results the dispersion experiments for the river water are executed. For the experiments, we focus on the tide effects and wind effects on the processes. Four cases of systematic experiments are conducted. They comprise the followings: a reference case with no tide and no wind, of tide only, of wind only, and of both tide and wind. Throughout this study, monthly mean values are used for the Kuroshio Current input in the southern boundary of the model domain, for the transport through the Korea Strait, for the river discharge, for the sea surface wind, and for the heat exchange rate across the air-sea interface. From the experiments, we obtained the following results. The circulation of the seas in winter is dependent on the very strong monsoon wind as several previous studies reported. The wintertime dispersion of the Yangtze River water follows the circulation pattern flowing southward along the east coast of China due to the strong monsoon wind. Some observed salinity distributions support these calculation results. In summertime, generally, low-salinity water from the river tends to spread southward and eastward as a result of energetic vertical mixing processes due to the strong tidal current, and to spread more eastward due to the southerly wind. The tide effect for the circulation and dispersion of the river water near the river mouth is a dominant factor, but the southerly wind is still also a considerable factor. Due to both effects, two major flow directions appear near the river mouth. One of them is a northern branch flow in the northeast area of the river mouth moving eastward mainly due to the weakened southerly wind. The other is a southern branch flow directed toward the southeastern area off the river mouth mostly caused by tide and wind effects. In this case, however, the tide effect is more dominant than the wind effect. The distribution of the low salinity water follows the circulation pattern fairly well.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.1
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• pp.89-95
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• 2019

Mooring observations of water temperature and salinity were conducted to investigate the effects of freshwater discharge patterns on the mouth of Nakdong River from April 2017 to March 2018. More than $500-1000m^3\;s^{-1}\;d^{-1}$ of freshwater was frequently discharged into the estuary throughout the rainy season, but less than $200m^3\;s^{-1}\;d^{-1}$ was discharged through the normal season. Sluice gates of the estuarine barrage operated depending on the tide level during spring tide, but they were constantly open during neap tide. Water temperature and salinity fluctuated regularly with intermittent discharges of freshwater, whereas they were stable while freshwater discharge was continuous. Mean salinity was 29 during the study period. Salinity exceeded the mean value in the normal season and rapidly recovered after a temporary reduction. In contrast, water with salinity below the mean value prevailed in the estuary for three months over the rainy season. These results indicate that water temperature and salinity were affected by the amount of freshwater discharge, as well as the frequency of discharge on a large scale and the time over which the freshwater discharge continued.

• Journal of Marine Life Science
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• v.1 no.1
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• pp.50-55
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• 2016

Glucose was continuously increased as time was elapsed under the temperature at 6℃ and 4℃. NH₃ was significantly increased at 4℃. AST was increased as temperature and salinity were decreased which indicated that it was affected by temperature, salinity and interaction of temperature×salinity. ALT was significantly increased as temperature was decreased. Free amino acid contents, excluding aspartic acid, threonine, serine and glycine were increased as temperature was decreased. This decreasing tendency was also observed when salinity was decreased. Taurine, aspartic acid, glutamic acid and arginine were significantly increased as salinity was decreased, while glycine, alanine, methionine, tyrosine, and histidine were decreased as salinity was decreased. The result of this study suggested that transport condition to minimize the stress is considered in the range of 30~34 psu, 8~10℃.

• Ocean Science Journal
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• v.40 no.2
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• pp.79-89
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• 2005

Laboratory radiotracer experiments were conducted to determine assimilation efficiencies (AE) from ingested algal food and oxic sediment particles, uptake rates from the dissolved phase, and the efflux rates of Cd, Cr and Zn in the Asiatic clam Corbicula fluminea. Among three elements, AE from both algal and sediment food was greatest for Cd, followed by Zn and Cr. The AEs of tested elements from algal food (Phaeodactylum tricornutum) were consistently higher than those from sediments at a given salinity and temperature. The influence of salinity (0, 4 and 8 psu) and temperature (5, 13 and $21^{\circ}C$) on the metal AEs was not evident for most tested elements, except Cd AEs from sediment. The rate constant of metal uptake from the dissolved phase $(k_u)$ was greatest for Cd, followed by Zn and Cr in freshwater media. However, in saline water, the $(k_u)$ of Zn were greater than those of Cd. The influx rate of all tested metals increased with temperature. The efflux rate constant was greatest for Cr $(0.02\;d^{-1})$, followed by Zn $(0.010{\sim}0.017\;d^{-1})$ and $Cd\;(0.006\;d^{-1})$. The efflux rate constant for Zn in clam tissues depurated in 0 psu $(0.017\;d^{-1})$ was faster than that in 8 psu $(0.010\;d^{-1})$. Overall results showed that the variation of salinity and temperature in estuarine systems can considerably influence the metal bioaccumulation potential in the estuarine clam C. fluminea. The relatively high Cd accumulation capacity of C. fluminea characterized by the high AE, high dissolved influx rate and low efflux rate, suggested that this clam species can be used as an efficient biomonitor for the Cd contamination in freshwater and estuarine environments.

• Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.161-166
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• 2005

We examined the variation in survival and the respiration and filtration rates of Tresus keenae in response to changes in water temperature and salinity. The survivorship of animals exposed to temperatures below $25^{\circ}C$ for 7 days was $80\%$; however, all test animals died on the fourth day at $28^{\circ}C$. The upper lethal temperature over 7 days was $25.9^{\circ}C$. After exposure to lower temperatures, $93\%$ ofthe animals survived at temperatures over $5^{\circ}C$ for 10 days. Survivorship rapidly decreased below $4^{\circ}C$ with all test animals dying at $2^{\circ}C$ on the eighth day. The $LT_{50}$ over 10 days was $4.8^{\circ}C$. The respiration and filtration rates of T. keenae increased as temperature increased. It is believed that energy consumption increases as a result of the increased respiration rate at temperatures above the upper lethal temperature. At temperatures below the lower lethal temperature, the metabolic rate of T. keenae was substantially lowered. In response to changes in salinity, the survivorship of T. keenae was $90\%$ at 30.2 psu after exposure for 5 days; at below 26.8 psu, all test animals died by the fifth day. The $LS_{50}$ was 29.1 psu. As salinity decreased, both the respiration rate and the filtration rate decreased. At 23.5 psu, the respiration and filtration rates decreased by 48 and $34\%$, respectively. These data have implications for increasing efficiency in the production and management of shellfish aquaculture farms.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.2 s.25
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• pp.99-106
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• 2006

The fate of chemical pollutants in the aquatic environment is generally considered to be strongly influenced by environmental factors such as pH, salinity and electrostatic charges on the surface of particles ai well as by the characteristic of chemicals. Oxolinic acid was measured by chemical analysis using HPLC to determine the effect of salinity, pH and suspended solids on chemical binding and by bioassay for measuring bioactivity. The higher contentration of suspended solids in the medium, the lower concentration of oxolinic and was detected in measurements from by both HPLC and biosssay analysis. This indicates particle may have a stronger binding or absorption effect on oxolinic acid. Bioassay analysis showed weaker bioacivity at higher salinity and pH 7.0, but this result of bioassay analysis was different from the result of HPLC.

• The Plant Pathology Journal
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• v.37 no.6
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• pp.662-672
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• 2021

Plant growth-promoting bacteria improve plant growth under abiotic stress conditions. However, their effects on microbial succession in the rhizosphere are poorly understood. In this study, the inoculants of Bacillus mesonae strain H20-5 were administered to tomato plants grown in soils with different salinity levels (EC of 2, 4, and 6 dS/m). The bacterial communities in the bulk and rhizosphere soils were examined 14 days after H20-5 treatment using Illumina MiSeq sequencing of the bacterial 16S rRNA gene. Although the abundance of H20-5 rapidly decreased in the bulk and rhizosphere soils, a shift in the bacterial community was observed following H20-5 treatment. The variation in bacterial communities due to H20-5 treatment was higher in the rhizosphere than in the bulk soils. Additionally, the bacterial species richness and diversity were greater in the H20-5 treated rhizosphere than in the control. The composition and structure of the bacterial communities varied with soil salinity levels, and those in the H20-5 treated rhizosphere soil were clustered. The members of Actinobacteria genera, including Kineosporia, Virgisporangium, Actinoplanes, Gaiella, Blastococcus, and Solirubrobacter, were enriched in the H20-5 treated rhizosphere soils. The microbial co-occurrence network of the bacterial community in the H20-5 treated rhizosphere soils had more modules and keystone taxa compared to the control. These findings revealed that the strain H20-5 induced systemic tolerance in tomato plants and influenced the diversity, composition, structure, and network of bacterial communities. The bacterial community in the H20-5 treated rhizosphere soils also appeared to be relatively stable to soil salinity changes.

• Journal of Marine Life Science
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• v.2 no.1
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• pp.34-38
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• 2017

FK506BP (FK506 binding protein 12) is a small peptide with a single FK506BP domain. It is involved in suppression of immune response, oxidative stress and inflammation. The purpose of this study was to investigate the gene expression of FK506BP in red seabream (Pagrus major) exposure to low water temperature (8℃, 33 psu) and low salinity (20℃, 10 psu). Results showed that, the expression of FK506BP was significantly increased in the experiment groups, such as low water temperature (8℃, 33 psu), and low salinity (20℃, 10 psu). These results suggest that FK506BP was played roles in biomarker gene on the environmental stress such as water temperature and salinity.

• Journal of Marine Life Science
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• v.2 no.2
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• pp.70-74
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• 2017

Interleukin-1 (IL-1) is one of the proinflammatory cytokines, after IL-1 binds to IL-1RI, IL-1RacP (interleukin-1 receptor accessory protein) joins with IL-1/IL-1RI to form a complex, and leading to cell activation. IL-1RAcP is involved in immune response, stress and apoptosis. The purpose of this study was to investigate the gene expression of IL-1RAcP in red seabream (Pagrus major) exposure to low water temperature (8℃, 33 psu) and low salinity (20℃, 10 psu). Results showed that, the expression of IL-1RAcP was significantly increased in the experiment groups, such as low water temperature (8℃, 33 psu), and low salinity (20℃, 10 psu). These results suggest that IL-1RAcP was played roles in biomarker gene on the environmental stress such as low water temperature and low salinity.