• The Korean Journal of Malacology
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• v.30 no.4
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• pp.421-428
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• 2014

Total 20 surface sediments were collected in Anjung bay to investigate the physicochemical environment and heavy metal contents. The physicochemical investigation ranged from 6.41% to 11.68% (average $9.52{\pm}1.28%$) for ignition loss (IL), from 17.99 mg/g to 43.84 mg/g (average $27.53{\pm}6.39mg/g$) for chemical oxygen demand (COD), and from 0.05 mg/g to 0.61 mg/g (average $0.17{\pm}0.14mg/g$) for acid volatile sulfide (AVS) with significant correlation between water content (W/C) and COD. A contour of spatial distribution indicated higher organic pollution at the bottom of ascidian, Stylea clava, cultural waters. Most of metals contents was not exceeded the NOAA's effect range-low (ERL). Estimated enrichment factor (EF) ranging 0.96-1.12 indicated that the sediment environment of the studied waters was relatively pristine from heavy metal pollution in spite of increased vessel traffics, so far.

• The Journal of Engineering Geology
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• v.9 no.3
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• pp.207-225
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• 1999

Twenty water samples (eleven groundwater and nine geothermal water samples) were collected to elucidate hydrogeochemical characteristics of the groundwater and geothermal water in the Dongrae hot-spring area and its vicinity. Major and minor elements were analyzed for ground and geothermal water samples. Physicochemical properties of the groundwater and the geothermal water were examined and chemical composition of the two waters were compared. Factor and correlation analyses were carried out to simplify the physicochemical data into grouping some factors and to find interaction between them. The groundwaters belong to $Ca-HCO_3$ type, while the geothermal waters belong to Na-Cl type. The Na and Cl concentrations in the Dongrae hot-spring area are higher than those of other granite areas in South Korea. The Na/Cl weight ratio ranges from 0.7 to 1.3 for the geothermal waters. On the phase stability diagram groundwaters fall effectively in the field of stability of kaolinite, while geothermal waters fall in the stability field of microcline or kolinite depending on the chemical composition system. Based on the Na-K, Na-K-Ca and Na-K-Ca-Mg geothermometers, the geothermal reservoir is estimated to have equilibrium temperature between 115 and $145^{\circ}C$.

• Korean Journal of Ecology and Environment
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• v.52 no.2
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• pp.136-142
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• 2019

Water spider(Argyroneta aquatica) inhabits only a small size wetland in Eundae-ri, Yeoncheon-gun. In this study to investigate environmental factors influencing on population of A. aquatica, we analyzed the relationship between density of A. aquatica and various physicochemical and biological factors. Density of A. aquatica increased with small habitat area and high $NH_4$ and electric conductivity. The relationship between density of A. aquatica and prey or predator was low but the water spider decreased with density of Pomacea canaliculata. And density of A. aquatica was not related to the coverage of emergent plant. However density of A. aquatica decreased as the increase of floating plant and increased as the increase of submerged plant. These results indicated that aquatic plants are important in the habitat environment of A. aquatica. Therefore we suggest necessity of management strategies for the invasive species, P. canaliculata which is a notorious predator of aquatic plants.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.340-354
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• 2021

The aim of this study was to investigate the spatial and temporal distribution of phytoplankton biomass and community composition in Jinhae Bay on the southern coast of Korea. Phytoplankton pigment analysis was conducted using ultra performance liquid chromatography (UPLC) were conducted from April to December 2019 at seven stations. Temperature, salinity, and dissolved oxygen (DO) and inorganic nutrients (dissolved nitrogen, dissolved phosphorus, and orthosilicic acid) were measured to investigate the environmental factors associated with the structure of phytoplankton community. Phytoplankton biomass (Chl-a) was the highest in July (mean 15.4±4.3 ㎍/L) and the lowest in December (mean 3.5±0.6 ㎍/L). Fucoxanthin was the most abundant carotenoid and showed a similar variation pattern to Chl-a, peridinin, and Chl-b. Phytoplankton community composition analysis showed that diatoms were a predominant group with an average abundance of 70 % whereas chlorophytes, cryptophytes, and dinoflagellates often appeared with lower averages. Further, the dominance of diatoms was closely correlated with water temperature and N:P ratio, which might be influenced by high temperatures in the summer and nutrient loading from the land. Additionally, freshwater and nutrient input by rainfall was estimated to be the most important environmental factor. Hence, the spatial and temporal variations in the composition of phytoplankton pigments and phytoplankton community were correlated with physicochemical and environmental parameters.

• Interdisciplinary Bio Central
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• v.6 no.4
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• pp.3.1-3.10
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• 2014

Amino acid substitution matrices are essential tools for protein sequence analysis, homology sequence search in protein databases and multiple sequence alignment. The PAM matrix was the first widely used amino acid substitution matrix. The BLOSUM series then succeeded the PAM matrix. Most substitution matrixes were developed by using the statistical frequency of substitution between each amino acid at blocks representing groups of protein families or related proteins. However, substitution of amino acids is based on the similarity of physiochemical properties of each amino acid. In this study, a new approach was used to obtain major physiochemical properties in multiple sequence alignment. Frequency of amino acid substitution in multiple sequence alignment database and selected attributes of amino acids in physiochemical properties database were merged. This merged data showed the major physiochemical properties through principle components analysis. Using factor analysis, these four principle components were interpreted as flexibility of electronic movement, polarity, negative charge and structural flexibility. Applying these four components, BAPS was constructed and validated for accuracy. When comparing receiver operated characteristic ($ROC_{50}$) values, BAPS scored slightly lower than BLOSUM and PAM. However, when evaluating for accuracy by comparing results from multiple sequence alignment with the structural alignment results of two test data sets with known three-dimensional structure in the homologous structure alignment database, the result of the test for BAPS was comparatively equivalent or better than results for prior matrices including PAM, Gonnet, Identity and Genetic code matrix.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.160-166
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• 2007

Response surface methodology (RSM) was used for the optimization of the baking process of cookies made with onion powders (onion cookie). Experiments were carried out according to a central composite design, selecting onion powder content $(1.15{\sim}8.86%)$ and baking temperature $(155.9{\sim}184.1^{\circ}C)$ as independent variables and pH, titratable acidity, moisture content, density, spread factor, CIE color parameters $(L^{\ast}-$, $a^{\ast}-$, and $b^{\ast}-values)$, and hardness as response variables. pH decreased with increasing amount of onion powder and baking temperature. Moisture content also decreased as the baking temperature increased. $L^{\ast}-$ and $b^{\ast}-values$ decreased but $a^{\ast}-values$ increased with increasing onion content and baking temperature. Most polynomial models developed by RSM were highly effective to describe the relationships between the studied factors and the responses. Overall optimization, conducted by overlaying the contour plots under investigation, was able to point out the optimal range of the independent variables within which the six responses were simultaneously optimized. The point chosen as representative of this optimal region corresponded to 4.01% onion powder content and $161.84^{\circ}C$ baking temperature. The predicted dependent or response values in the optimal region were: pH＝6.87, moisture content＝2.77%, $L^{\ast}-value＝68.45$, $a^{\ast}-value＝1.98$, $b^{\ast}-value＝34.64$, and spread factor＝9.41.

• The Korean Journal of Food And Nutrition
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• v.31 no.4
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• pp.495-501
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• 2018

Ultraviolet B (UVB) exposure is a risk factor for skin damage resulting in oxidative stress, inflammation, and cell death. The purpose of this study was to investigate the physicochemical properties of Platycodon grandiflorum (PG) to improve its biological activities using a three-step steaming process. We investigated the protective effects of PG and steamed PG extracts on human dermal fibroblasts (HDFs) against UVB radiation-induced oxidative stress and inflammation as well as the underlying mechanisms. The antioxidant potential of the PG extracts was evaluated by measuring the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) scavenging activity. ABTS and DPPH were shown by the 0, 30, and 70% ethanol extracts of 2S-PG and 3S-PG ($IC_{50}$, 28~45 and $27{\sim}30{\mu}g/mL$, respectively). Treatment of UVB-irradiated cells with steamed PG ($25{\sim}400{\mu}g/mL$) did not affect their viability. The streamed PG extract suppressed UVB-induced generation of reactive oxygen species (ROS). In addition, streamed PG extract reduced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein expression in UVB-irradiated HDF, regulating nuclear factor $(NF)-{\kappa}B$ expression. These findings suggest that steamed PG extract may be potentially effective against inflammation associated with UVB-induced oxidation stress.

• Korean journal of food and cookery science
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• v.30 no.4
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• pp.454-462
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• 2014

This study aimed at the optimization and development of rice snack by response surface methodology (RSM). The effect of rice soaking time and additional ratio of soybean milk on physicochemical properties and sensory evaluation of dried rice flour for non-fried snack was studied. After soaking for 0 to 12 days, Baekjinju rice was milled and then air-dried. A quadratic model was selected for weight, volume, hardness, taste and appearance. Two-factor interaction model was selected for expansibility, color and overall preference. A linear model was selected for yellowness and flavor. Weight, hardness and appearance were increased and decreased thereafter as rice soaking time increased, but the volume was reversed. Expansibility, color, taste and flavor were decreased as rice soaking time increased, but yellowness was reversed. Weight and overall preference decreased as additional ratio of soybean milk increased, but volume, expansibility and yellowness were reversed. Hardness, taste and appearance were increased after initial decrease as additional ratio of soybean milk increased, color and flavor were not changed by additional ratio of soybean milk. The optimum conditions of each factor were set to where the rice soaking time and additional ratio of soybean milk were at their minimum. Weight, volume, expansibility, yellowness, hardness, color, taste, flavor, appearance and overall preference were established at maximum level where the objective of the optimum was in level. Our data indicated the statistically predicted values of the highest desirability was 1.24 day of rice soaking time and 15.80% of additional ratio of soybean milk.

• Journal of Environmental Health Sciences
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• v.20 no.1
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• pp.75-82
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• 1994

Bioconcentration Factor (BCF) is known as important criteria for ecotoxicology on hazardous chemicals. But there is no standard method for determining BCF and reported BCFs were slightly different in accordance with authors. This study was performed with aims to determine BCFs on BPMC and Carbaryl. Carassius auratus(goldfish) be chosen as test organism and test period were 3-day, 5-day and 10-day. Extract solvents were n-hexane and acetonitrile. GC-ECD was used to detecting carbamates. The obtained results were as follows: 1. It was possible to determine short term BCF$_s$ of Carbaryl or BPMC through relatively simple procedure. 2. BCF$_3$ of Carbaryl in concentration of 1, 2, 5, 10 ppm were 0.34 $\pm$ 0.06, 0.18 $\pm$ 0.02, 0.10 $\pm$ 0.01, 0.06 $\pm$ 0.01 respectively. BCF$_5$ of Carbaryl were 0.34 $\pm$ 0.05, 0.18 $\pm$ 0.02, 0.13 $\pm$ 0.01 and 0.07 $\pm$ 0.01, BCF$_{10}3$ of Carbaryl were 0.45 $\pm$ 0.05, 0.27 $\pm$ 0.02, 0.16 $\pm$ 0.02 and 0.09 $\pm$ 0.01. BCF$_3$ of BPMC in concentration of 1, 2, 5 ppm were 4.66 $\pm$ 0.17, 2.64 $\pm$ 0.49, 1.88 $\pm$ 0.24 respectively. BCF$_5$ of BPMC were 4.09 $\pm$ 0.50, 2.42 $\pm$ 0.37 and 1.83 $\pm$ 0.15. 3. BCF$_s$ of BPMC were decreased as increasing concentration. However, BPMC concentration in fish were increased in contrast to BCF. But more concentrated BPMC was found in fish 3-day test than found concentration in fish 5-day test. 4. Same trend appeared in Carbaryl. BCF$_s$ of Carbaryl were decreased as increasing concentration and prolonging test period. But found Carbaryl concentration in fish were increased. 5. BCF$_s$ of BPMC were higher than that of Carbaryl by 10 times, in spite of the physicochemical properties of the two carbamates were similar to each other. Further study is recommended to find out the reason of the difference.

• Journal of Environmental Science International
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• v.9 no.3
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• pp.241-252
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• 2000

Twenty-two water samples(fifteen groundwater and seven geothermal water samples) were collected to elucidate chemical characteristics of the ground and geothermal waters in the Haeundae hot spring area and its vicinity. Major and honor elements were analyzed for ground and geothermal water samples. The concentrations of $K^+$, Na+$, $Ca^{2+}$, $SO_4^{2-}$, $Cl^-$, ^F^-$ and $SiO_2$ were higher in the geothermal water samples than the groundwater samples except $HCO_3^- and Mg^{2+}$ ions. Based on the contents of Fe, Zn, Cu, Al, Mn and Pb, some of the ground and geothermal water samples are contaminated by anthropogenic sources. The ground waters shown on the Piper diagram belong to $Ca-HCO_3$ type, while the geothermal waters Na-Cl type. The graphs of $Cl^-$ versus $Na^+$, $Ca^{2+}, Mg^{2+}, K^+, SO_4^{2-} and HCO_3^-$ indicate that the groundwater is related partly with mineral-water reaction and partly with anthropogenic contamination, while the geothermal water is related with saline water. On the phase stability diagram, groundwater and thermal water mostly fall in the field of stability of kaolinite. This indicates that the ground and geothermal waters proceed with forming kaolinite. Factor and correlation analyses were carried out to simplify the physicochemical data into grouping some factors and to find interaction between them. Based on the Na-K, Na-K-Ca and Na-K-Ca-Mg geothermometers and silica geothermometers, the geothermal reservoir is estimated to have equilibrium temperature between 125${$\mid$circ}C$ and 160${$\mid$circ}C$.