• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.895-897
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• 2005

• Ocean Science Journal
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• v.41 no.4
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• pp.211-219
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• 2006

A comparison was made of population of the economically important cockle Anadara (=Scapharca) broughtoni (Bivalvia, Arcidae) inhabiting different areas of the Razdolnaya River estuary at the head of Amurskii Bay (Peter the Great Gulf, East Sea). Also, changes in cockle population density and structure, as well as in cockle growth rates during the last 20 years were studied. In all years of investigation, the morphometrical parameters and growth rates of cockles were smaller at the sites located close to the River mouth than farther down-estuary. The differences can be attributed to higher concentration of suspended particulate matter, decreased salinity and water temperature, as well as a longer exposure to these unfavorable environmental factors at sites located close to the River mouth, compared to farther sites. For two decades, cockle population density had decreased by almost 30 times at some sites in the River estuary. The main reason for this population decline is commercial over-fishing of the cockle. Besides, for the last 20 years, linear parameters of the cockles in the population decreased approximately by 30% and weight parameters, almost two times. Cockle growth rates also decreased for this period. Evidently, these facts are due to the damaging effect of dredging.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.578-581
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• 2006

Fishery products were collected in seafood markets located on the southwestern coast of Korea between 2000 and 2004 and examined for the presence of Vibrio parahaemolyticus. This strain was detected in 138 of 843 samples (16.4%) that included dams, eels, crabs, octopuses, and cockles. The number of positive findings for V. parahaemolyticus among fishery products was the highest in dams at 23.6% followed by eels at 22.1%, crabs at 21.1%, octopuses at 18.0%, and cockles at 14.3%. V. parahaemolyticus was detected with overall frequencies of 15.3, 14.8, 13.8, 21.6, and 18.6% from 2000 to 2004, respectively. The monthly occurrence of the organism rapidly increased to over 20% between June and October. The monthly cases of food borne disease caused by V. parahaemolyticus in Korea over the last five years began to increase in August and reached its peak in September. However, the potential for outbreaks of food borne disease caused by V. parahaemolyticus was relatively minor between November and April. Consequently, this study shows that fishery products harvested from June to October must be handled sanitarily in Korea.

• The Korean Journal of Malacology
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• v.29 no.3
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• pp.163-169
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• 2013

In the present study, the seven primers BION-33, BION-34, BION-37, BION-41, BION-44, BION-45 and BION-42 generated the total number of loci, average number of loci per lane and specific loci in Hongseong, Yeosu and Goheung population of F. mutica, respectively. 7 primers generated 19 specific loci in the Hongseong population, 29.3 in the Yeosu population and 23.1 in the Goheung population, respectively. Especially, the decamer primer BION-37 generated 7 unique loci to each population, which were identifying each population, approximately 700 bp in Hongseong population. In this study, the dendrogram obtained by the seven primers indicates three genetic clusters: cluster 1 (HONGSEONG 01-HONGSEONG 07), cluster 2 (YEOSU 08-YEOSU 14) and cluster 3 (GOHEUNG 15-GOHEUNG 21). Among the twenty one cockles, the shortest genetic distance that displayed significant molecular differences was between individuals 17 and 19 from the Goheung population (genetic distance = 0.051), while the longest genetic distance among the twenty-one cockle individuals that displayed significant molecular differences was between individuals HONGSEONG no. 03 and YEOSU no. 12 (genetic distance = 0.616). Relatively, individuals of YEOSU population were fairly closely related to that of GOHEUNG population. Ultimately, PCR fragments revealed of in this study may be useful as a DNA marker the three geographic populations to distinguish.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.31-43
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• 1968

1. Shell height frequencies of the fresh-water cockle, Corbicula elatior, sampled in the period of 1960 to 1963, are analyzed to assess the age composition and average growth pattern. Cumulative frequencies in a sample are traced on a probability scale, and the points of inflection on a probability graph are assumed to dissect age groups. 2. Seasonal growth of Corbicula elatior in the Naktong River ill as follows: Young cockles settle down on river-bed by June and grow rapidly during the summer season, reaching 14mm in shell height by October. From October to April the growth is very slow. The rapid growth in the second year starts around in May. 3. Survival rate per year for Corbicula elatior in the Naktong River is estimated to be $5\~10\%$ by age composition.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.1
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• pp.43-48
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• 2010

This study was designed to evaluate whether the addition of sediment improvements with natural materials to water tanks influenced the hematologic properties and muscle glycogen content of the blood cockle, Tegillarca granosa under laboratory conditions. Following a 10-d matured period of sediment improvements, blood cockles were subjected to 4 groups (0, 100, 300, $800\;g/m^2$) of sediment improvements for 14-d Only one individual died at $800g/m^2$ after 48-h Whole blood, hematocrit value and hemoglobin concentration of blood cockle were changed little by sediment improvements, however, both glucose and glycogen were increased more compared with those of the control groups.

• The Plant Pathology Journal
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• v.33 no.4
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• pp.370-381
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• 2017

Rathayibacter tritici, which is a Gram positive, plant pathogenic, non-motile, and rod-shaped bacterium, causes spike blight in wheat and barley. For successful pathogenesis, R. tritici is associated with Anguina tritici, a nematode, which produces seed galls (ear cockles) in certain plant varieties and facilitates spread of infection. Despite significant efforts, little research is available on the mechanism of disease or bacteria-nematode association of this bacterium due to lack of genomic information. Here, we report the first complete genome sequence of R. tritici NCPPB 1953 with diverse features of this strain. The whole genome consists of one circular chromosome of 3,354,681 bp with a GC content of 69.48%. A total of 2,979 genes were predicted, comprising 2,866 protein coding genes and 49 RNA genes. The comparative genomic analyses between R. tritici NCPPB 1953 and R. toxicus strains identified 1,052 specific genes in R. tritici NCPPB 1953. Using the BlastKOALA database, we revealed that the flexible genome of R. tritici NCPPB 1953 is highly enriched in 'Environmental Information Processing' system and metabolic processes for diverse substrates. Furthermore, many specific genes of R. tritici NCPPB 1953 are distributed in substrate-binding proteins for extracellular signals including saccharides, lipids, phosphates, amino acids and metallic cations. These data provides clues on rapid and stable colonization of R. tritici for disease mechanism and nematode association.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.1
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• pp.33-39
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• 2024

This study explores the utilization of common marine wastes, specifically seashells, such as oysters and cockles, as alternative fine aggregates in construction materials. The considered seashells were cleaned and pre-processed for use as a substitute for aggregate in mortar. Cement mortar specimens were prepared under different conditions, such as substitution ratios and the cleaning status of the seashells. The compressive strength of the mortars specimens was evaluated, and the solid and porous structures of each specimen were analyzed using microstructure analysis methods such as XRD, SEM, and micro-CT. The results confirmed that oyster and cockle seashells are composed of different calcium carbonate polymorphs, and their microstructural characteristics influence the mechanical properties of the cement mortar specimens.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.237-242
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• 1998

This study was carried out to process canned ark shell with highly quality by management of proper processing conditions for prevention of oxidation and discoloration by heating. Ark shell has hemoglobin as blood pigment in red blood shell which same as other cockles. Hemoglobin is easy to come oxidation and browning reaction, and it has large contents of carotenoid as meat pigment. Proximate compositions in ark shell were 76.9% of moisture, 18.1% of crude protein, 1.8% of crude lipid, 1.3% of carbohydrate and 1.6% of crude ash. And contents of carotenoid and hemoglobin were 0.67~1.02mg% and 0.98~1.64g/dl, respectively. When the living ark shell was soaked in 2% NaCl solutions, about 89% of mud was removed after 10 hours soaking, and over 91% was removed when the pH was adjusted to 7.5. Carotenoid pigment were prepared that extracted from ark shell by using acetone. And determined visible spectrum were two peak at 452nm and 687nm, and λmax were 452nm. During thermal treatment at 95$^{\circ}C$, 111$^{\circ}C$, 116$^{\circ}C$ and 121$^{\circ}C$ for 60 minutes, retention ratio of carotenoid were 71.8%, 66.8%, 64.4% and 36.5%, and after 120 minutes retention ratio were 56.6%, 30.6%, 30.3% and 17.2%, respectively. When heated at 95$^{\circ}C$, 111$^{\circ}C$, 116$^{\circ}C$ and 121$^{\circ}C$, formation of browning material were increased at high temperature and long time treatment.