• Parasites, Hosts and Diseases
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• v.28 no.4
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• pp.213-220
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• 1990

The employees at the Pohang industrial area, where Clonarchis sinensis has been known to be endemic along the Hyungsan River, were examined parasitologically for clonorchiasis and a part of the infected cases were surveyed with a questionaire to outline the recent infection status of C. sinensis and epidemiological parameters in the area. Total of 3, 180 cases were tested by intra- dermal inoculation of C. sinensis antigen (Green Cross Co., Korea), and 834(26.2%) were found positive. Out of the positive cases, 598 were subjected to (ecal examination for helminth ova. The examination revealed 129(21.6%) ova Positive cases of C. sinensis, and Trichuris trichiura 1.7%, Ascaris lumbricoides 0.3%, and Metagonimus yokogawai 0.2%. The questionaire analysis showed some significant difFerences between the infected and non-infected(control) groups. The infected cases were less educated than the control, and they lived at the closer area to the river, and most of them lived there over 20 years. Also they preferred eating raw fresh water fish. Most of the detected cases were treated with prasiquantel and found negative for the eggs in 85.3% of them 1 year after the treatment. The present data reveal markedly decreased endemicity of clonorchiasis compared with previous prevalence rates but still clonorchiasis is endemic in the Hyungsan river basin. A comprehensive measure including case detection, treatment and education for parasite control should be applied to control clonorchiasis in such endemic areas.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.1
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• pp.1-14
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• 2017

For the removal of cesium (Cs) from high radioactive/high salt-laden liquid waste, this study synthesized a highly efficient composite adsorbent (potassium cobalt ferrocyanide (PCFC)-loaded chabazite (CHA)) and evaluated its applicability. The composite adsorbent used CHA, which could accommodate Cs as well as other molecules, as a supporting material and was synthesized by immobilizing the PCFC in the pores of CHA through stepwise impregnation/precipitation with $CoCl_2$ and $K_4Fe(CN)_6$ solutions. When CHA, with average particle size of more than $10{\mu}m$, is used in synthesizing the composite adsorbent, the PCFC particles were immobilized in a stable form. Also, the physical stability of the composite adsorbent was improved by optimizing the washing methodology to increase the purity of the composite adsorbent during the synthesis. The composite adsorbent obtained from the optimal synthesis showed a high adsorption rate of Cs in both fresh water (salt-free condition) and seawater (high-salt condition), and had a relatively high value of distribution coefficient (larger than $10^4mL{\cdot}g^{-1}$) regardless of the salt concentration. Therefore, the composite adsorbent synthesized in this study is an optimized material considering both the high selectivity of PCFC on Cs and the physical stability of CHA. It is proved that this composite adsorbent can remove rapidly Cs contained in high radioactive/high salt-laden liquid waste with high efficiency.

• The Journal of Engineering Geology
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• v.20 no.4
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• pp.425-436
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• 2010

We established a stochastic 3-D fracture network system for fractured rock masses located in Il-Gwang Mine, Busan, to explore the relationship between the acidity of mine drainage and fracture geometry. A field scanline survey and borehole image processing were performed to estimate the best probability distributions of fracture geometry parameters. The stochastic 3-D fracture network system constructed for the rock masses was validated and deemed to be successful. The 3-D fracture network model was suitable for developing conceptual ideas on fluid flow in fractures at a field experimental site. An injection well and three observation wells were drilled at the field experimental site to monitor the acidity of mine drainage induced by the injection of fresh water. The field experiment, which was run for 29 days, yielded a significant relationship (with a high coefficient of determination) between the fracture geometry parameters and the acidity of mine drainage. The results show that pH increased with increasing relative frequency of fracture strike, and decreased with increasing fracture density. The concentration of $SO^{2-}_4$ decreased with increasing relative frequency of fracture strike, and increased with increasing fracture density.

• Journal of the Korean Society of Food Culture
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• v.8 no.3
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• pp.267-274
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• 1993

This study was aimed to investigate the changes in textural properties of Korean radish and relevant chemical, enzymatic activities during salting. During salting, pH was decreased and total acidity was increased. The maximum compression and puncture forces of Korean radish were decreased significantly whereas cutting force was increased. From the force-distance curves, the break point and maximum force point disappeared in salted Korean radish whereas these appeared apparently in fresh one. Also, the number of peak obtained by three types of test from salted Korean radish was decreased. Hot water soluble pectin and 0.4% Na-hexametaphosphate soluble pectin were increased whereas 0.05 N-HCl soluble pectin were decreased significantly. Polygalacturonase activity were increased in Korean radish solid(RS) and Korean radish juice(RJ) until 4 days of salting. Pectin esterase activity were decreased in RS and RJ. Cx-cellulase activity did not appear initially, however, they began to show their activities after 2 days of salting and were increased in RJ although it was low.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.6
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• pp.738-749
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• 2016

To understand the characteristics of the spatio-temporal distribution of phytoplankton after barrage construction in the Nakdong River Estuary, this study investigated relevant environmental parameters and phytoplankton status based on bi-monthly samples collected from the Nakdong River Estuary itself from February 2013 to December 2015. Environmental parameters did not differ significantly across these years but did vary between zones and seasons. The results suggested that the upper zone was dominated by fresh-water diatoms, green algae, and blue-green algae, whereas the lower zone was mostly dominated by dinoflagellates. The presence of Stephanodiscus spp., Asterionellopsis formosa, and Microcystis spp. in the upper zone was related to the inflow of freshwater discharge by artificial control of dyke gates. The dominant phytoplankton species in this zone were dependent on temperature, wind speed, DIP, and DIN, while those in the lower zone were mostly dependent on nutrients and wind speed. In addition, at the lower zone, there were negative correlations between Prorocentrum donghaiense, DIN, and wind speed, with its abundance being higher during the summer than other seasons. Analysis of temporal variations did not indicate any significant differences in the upper zone but did reveal variations among seasons at the lower zone. Except in 2014, the lower zone could be divided into periods dominated by diatoms (October-April) and dinoflagellates (June-August). These results suggest that the characteristics of the phytoplankton community were influenced by changes in the inflow of freshwater species and nutrients given the difference in the range affected by freshwater discharge.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.228-232
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• 2007

We have also clarified the effects of the different substrates; (perlite, peatmoss and granular rock-wool) on the plant growth and the mineral contents of Campanula takesimana until 70 days after transplanting. Overall plant growth in terms of plant height, stem diameter, number of leaves, root length, fresh and dry weight of shoot and root were increased in the order of that mixed perlite and peat moss (50 : 50, v/v)>peat moss (100%)>perlite (100%)>granular rock wool (100%). Mineral contents in plants were much more in the order of potassium $(15.38-43.91cmol^+/kg)$, calcium $(5.48-7.78cmol^+/kg)$, magnesium $(4.38-6.55cmol^+/kg)$ and sodium $(1.25-1.69cmol^+/kg)$. The higher mineral contents of plants were also most made in the mixed substrates of perlite and peat moss (50 : 50, v/v).

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.252-260
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• 2008

This study was conducted to observe the characteristics of mineral nutrient uptake of single-node cutting rose 'Versilla' and to determine optimal nutrient solution control method for soilless culture of 'Versilla' in a closed hydroponic system. Nutrient solution was managed by five different control methods: macro- and micro-element control in aeroponic system (M&M), macroelement control in aeroponic system (M), nutrient solution supplement in aeroponic system (S); electrical conductivity (EC) control in aeroponic system(EC-A); EC control in deep flow technique system(EC-D). The concentration of $NO_3$-N exceeds optimal range whereas P and Mg decreased at the later stage of plant growth with the EC control method, EC-A and EC-D. The overall mineral nutrient content increased with S. On the other hand the nutrient content at the root environment was maintained optimal with M&M and M. The nutrient solution control methods had significantly effect on the cut-flower quality. In the M&M and M, flower length, fresh weight and root activity were higher than those with the other mineral nutrients control methods. The maximal efficiency of photochemistry (Fv/Fm) was higher for M&M, M and S than that with EC-A and EC-D. Based on the above results, it is highly recommended to control nutrient solution by mineral nutrient control methods (M&M and M) in a closed hydroponic system for single-node cutting rose, 'Versillia'.

• Journal of Nutrition and Health
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• v.49 no.2
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• pp.88-98
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• 2016

Purpose: We recruited 118 women in their early 20's to examine the relationship between sodium intake and salty taste thresholds and preference. We also examined the association of salty taste preference with sodium-related dietary behaviors and major dishes contributing to sodium intake. Methods: Daily sodium intake was estimated using a 127-item dish-frequency questionnaire. Salty taste thresholds and preference were measured using rating scales using water solution of NaCl and a self-administered questionnaire based on a Likert scale, respectively. Results: Salty taste preference showed positive correlation with daily sodium intake and sodium intake-increasing behaviors, and inverse association with sodium intake-decreasing behaviors, including salt and soy sauce use at the table, the frequency of eating out and home delivery of foods, broth consumption of soup, stew or noodle soup, the use of ready-to-serve or processed foods, fresh vegetable intake, and the accommodating attitude toward bland food. Intake of sodium-contributing dishes, including ramen, spicy soft-tofu stew, radish kimchi, and dishes containing kimchi, also showed positive association with salty taste preference. Unexpectedly, detection and recognition thresholds of salty taste showed no association with salty taste preference, sodium intake, and sodium-related dietary behaviors. Conclusion: These findings suggest that salty taste preference could reflect sodium intake of individuals rather than thresholds of saltiness, and may be used as a simple and effective proxy for usual sodium intake.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.170-176
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• 1984

This study was directed to define the taste compounds of crucian carp, Carassius caressius, free amino acids, nucleotides and their related compounds, organic bases, sugars, organic acids and minerals in the extracts of crucian carp were analyzed, and then followed by sensory evaluation of synthetic extracts prepared from 44 pure chemicals on the basis of the analytical data. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in taste profile were assessed. In free amino acid composition, histidine was dominant occupying $46\%$ of the total free amino acids. The other abundant free amino acids were glycine, lysine, alanine and taurine. As for the nucleotides, IMP was dominant showing about $80\%$ of the total of nucleotides. The most abundant organic base was total creatinine. The content of betaine was poor and TMAO were trace in content. The main organic acids were succinic, propionic, butyric and valeric acid. Small amount of glucose, fructose and inositol were detected and ribose and arabinose were trace in content $K^+,\;Na^+,\;PO_4^{3-}\;and\;Cl^-$ were found to be the major ions and small amount of $Ca^{++}\;and\;Mg^{2+}$ were deleted. Judging from the results of omission test, the major components which contribute to produce the taste were serine, glutamic acid, lysine, arginine, tyrosine, phenylalanine, IMP, $Na^+,\;K^+\;and\;PO_4^{3-}$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.33-39
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• 1984

In order to elucidate the taste compounds of wild eel, Anguilla japonica, free amino acids, nucleotides and their related compounds, organic bases, sugars, organic acids and minerals were analyzed, and then followed by organoleptic test of synthetic extract prepared on the basis of the analytical data. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in profile were assessed. In free amino acid composition, lysine was dominant occupying $25\%$ of total free amino acid. The other abundant amino acids were glycine, arginine, alanine and histidine. From the results of analysis of nucleotides, IMP was dominant showing about $70\%$ of total nucleotides while ATP, ADP, AMP, inosine and hypoxanthine were low in content. Among organic bases total creatinine was abundant. The amount of betaine was 24 mg/100 g. The main organic acid were butyric acid, valeric acid and succinic acid. As for the sugars, glucose and inositol were 1-2 mg/ 100g in content. $K^+,\;Na^+,\;PO_{4}^{3-}\;and\;Cl^-$ were found to be the major ions. From the results of omission test the major components which contribute to produce the taste were glycine, serine, glutamic acid, IMP, $Na^+,\;K^+,\;Cl^-,\;PO_{4}^{3-}$, lysine, alanine, isoleucine, aspartic acid and creatinine.