• Journal of the Korean Ceramic Society
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• v.17 no.1
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• pp.27-34
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• 1980

The synthesis of glass-ceramic materials from glasses based on industrial wastes or natural rocks their physical properties were studied. Glasses of composition, CaO14.7∼16.1, MgO7.4∼9.0, Al2O38.3∼19.3, SiO2 48.9∼51.0wt% were prepared from domestic blast furnace slag, serpentine, sea sand and etc. with additions of chromic oxide, and fluoride as nucleating agent. The glasses were subjected to controlled heat treatments and yielded fine microstructure of glass-ceramics which were composed of monocrystalline phase of aluminous diopside. X-ray diffraction techniques were adopted to identify the crystalline phases and to determine the degree of crystallization quantitatively. Density, coefficient of thermal expansion, young's modulus, microhardness and modulus of rupture were measured and the resulting properties were discussed in terms of the heat-treatment conditions, the degree of crystallization, species of crystaline phase, the microstructures formed in glass-cramics and the chemical compositions of mother glasses.

• Journal of the Korean Wood Science and Technology
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• v.26 no.4
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• pp.56-60
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• 1998

The bark of Fraxinus rhynchophylla, one of ash trees grown in domestic, was collected, extracted with acetone-$H_2O$(7:3, v/v) and freeze dried to give 50g of ethylacetate soluble powder. A portion of the freeze dried powder was chromatographed on a Sephadex LH-20 and a TSK 40F column using a series of aqueous methanol and ethanol-hexane mixture as eluents. The extractives contained a large amount of coumarin derivatives in addition to a small amount of ester compounds such as ligstroside and oleuropein which have not been isolated from this tree species yet. Some spectrometric analyses such as NMR and FAB-MS including TLC were performed to identify the structures of the isolated ester compounds.

• Parasites, Hosts and Diseases
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• v.44 no.2 s.138
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• pp.145-149
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• 2006

Three cases of cutaneous larva migrans (CLM) were diagnosed in a returnee from a trip to Thailand and in 2 domestic farmers during July and September, 2003. The linear and serpiginous skin lesions on the lower extremities were presented in all 3 cases. Routine laboratory findings were normal. In the imported case, a $650\times30{\mu}m$ sized filariform nematode larva, presumably a species of hookworm, was detected in the lesion. All cases were treat-ed with 400 mg albendazole once daily for 3-5 days, and their skin lesions gradually improved. In the present study, a causative agent of CLM was isolated for the first time in the Republic of Korea. Moreover, we speculate that CLM is prevalent in farmers who are in frequent contact with soil in the Republic of Korea.

• Korean Journal of Veterinary Research
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• v.59 no.2
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• pp.69-74
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• 2019

Avian malaria is one of the most important general blood parasites of poultry in Southeast Asia. Plasmodium (P.) juxtanucleare causes avian malaria in wild and domestic fowl. This study aimed to identify and characterize the Plasmodium species infecting in Thai native fowl. Blood samples were collected for microscopic examination, followed by detection of the Plasmodium cox I gene by using PCR. Five of the 10 sampled fowl had the desired 588 base pair amplicons. Sequence analysis of the five amplicons indicated that the nucleotide and amino acid sequences were homologous to each other and were closely related (100% identity) to a P. juxtanucleare strain isolated in Japan (AB250415). Furthermore, the phylogenetic tree of the cox I gene showed that the P. juxtanucleare in this study were grouped together and clustered with the Japan strain. The presence of P. juxtanucleare described in this study is the first report of P. juxtanucleare in the Thai native fowl of Thailand.

• The Journal of Fisheries Business Administration
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• v.53 no.4
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• pp.51-67
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• 2022

The Korean tariff rate for fishery products is a single tax rate of 10% for live fish and frozen seafood, and 20% for all others. Since FTAs have been concluded with several countries, the tariffs is not an appropriate means to protect domestic fishery producers. The differential tariff rate according to the scientific name (genus) of the fishery products, which was implemented 30 years ago to protect fishery products produced in the Korean coastal waters has lost its original purpose. It seems that future fishery trade policy should focus on IUU prevention, hygiene and safety of consumers rather than protecting fishery producers through customs tariffs. This paper suggest that a paradigm shift in the fishery producers protection policies such as direct financial support from the state, protection and development of fishery resources, and support for fostering the 6th industry rather than indirect protection through tariffs.

• International Journal of Industrial Entomology and Biomaterials
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• v.47 no.2
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• pp.134-139
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• 2023

SIRT5 and PRDx1 play crucial roles in cancer and are involved in the basic mechanisms of reactive oxygen species detoxification. In our previous studies, we showed that hemolymph extracts of immune-challenged Bombyx mori have antioxidant properties. Following H₂O₂ stimulation, immune-challenged B. mori hemolymph extracts elicited SIRT5 downregulation activity, reaching effective activity at the highest concentration of 100 ppm. Additionally, cells treated with immune-challenged B. mori hemolymph extracts demonstrated increased PRDx1 mRNA expression compared to that of PBS-treated cells. Therefore, immune-challenged B. mori hemolymph extracts offer a potential auxiliary means of treating drug-resistant tumors through downregulation of SIRT5 and upregulation of PRDx1 expression. Nevertheless, further studies on the effects of B. mori hemolymph on SIRT5 and PRDx1 regulation are pertinent for using it as a food or pharmaceutical material and understanding its therapeutic effect on tumors, including those that are drug-resistant.

• Journal of fish pathology
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• v.36 no.2
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• pp.409-414
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• 2023

Ellipsoidal-shaped spores with two polar capsules were detected in leather carp (Cyprinus carpio nudus) muscle. 18S rDNA gene analysis of the spore showed a 99.58% match to Myxobolus artus, a myxozoan parasite. As a result of phylogenetic analysis using the Bayesian inference model and maximum likelihood model among other Myxobolus species, the isolate in the present study belonged to the M. artus cluster. This is the first case report of M. artus infection detected in domestic aquaculture organisms in Korea.

• The Journal of Fisheries Business Administration
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• v.37 no.1 s.70
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• pp.45-71
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• 2006

The main objective of this study is to analyze problems of the Country of Origin Labeling(COOL) in small live fish(SLF) trade by applying the asymmetric information theory which is called ${\ulcorner}$Lemon Market Theory${\lrcorner}$. The purpose of importing SLF is to enhance fishing household income and import substitution effect as well. SLF importation is quite different in its nature from importing general fish and fish products for final/direct consumption. SLF are imported for the purpose of domestic aquaculture and naturalization where domestic production/supply of SLF is less than domestic demand for or such species are not native to Korean waters. Information asymmetric problems arise even in SLF trade as the same way in general goods and services. However, the information asymmetry issues in SLF trade are much more complex than non-living goods because SLF are traded in the live state. To alleviate such problems the Korean government initiated the general COOL scheme to imported SLF. However, many experts argues that such policy on SLF would not be appropriate because of SLF's very nature. Applying the lemon market theory, we can analyze how information discovery schemes are able to signal correct information to SLF trading parties and to result in more symmetric information in SLF trade markets. This research carried out a case study about small live eel(SLF) trade and its farming. The results showed that applying the COOL to small live eels just right upon coming into fish farms tends to increase substantially fish farmer's income and at the same time to lower unnecessary transaction costs. In particular, such transaction costs by imposing simply the general COOL on SLF may easily outweigh its benefits. For instance, to resolve the problems, the Korean ministry of agriculture and forestry(KMAF) has developed a quite different COOL rules from the general ones and has applied them to imported live cattle and medium/small livestocks. The KMAF's differentiated COOL policy on some imported livestocks may be a good case which can be applied to imported SLF. In addition to the differentiated COOL on SLF, Sanitary and Phytosanitary (SPS) and traceability system would play crucial complementary roles in alleviating information asymmetry problems in SLF trade. Advanced fisheries tend to strengthen their SPS system rather than to adopt the general comprehensive COOL schemes into imported SLF trades and domestic market exchanges.

• Parasites, Hosts and Diseases
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• v.52 no.3
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• pp.281-285
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• 2014

Ticks were collected from 35 animals from 5 provinces and 3 metropolitan cities during 2012. Ticks also were collected by tick drag from 4 sites in Gyeonggi-do (2) and Jeollabuk-do (2) Provinces. A total of 612 ticks belonging to 6 species and 3 genera were collected from mammals and a bird (n=573) and by tick drag (n=39). Haemaphyalis longicornis (n=434) was the most commonly collected tick, followed by H. flava (158), Ixodes nipponensis (11), Amblyomma testudinarium (7), H. japonica (1), and H. formosensis (1). H. longicornis and H. flava were collected from all animal hosts examined. For animal hosts (n>1), the highest Tick Index (TI) was observed for domestic dogs (29.6), followed by Siberian roe deer (17.4), water deer (14.4), and raccoon dogs (1.3). A total of 402 H. longicornis (adults 86, 21.4%; nymphs 160, 39.8%; larvae 156, 38.9%) were collected from wild and domestic animals. A total of 158 H. flava (n=158) were collected from wild and domestic animals and 1 ring-necked pheasant, with a higher proportion of adults (103, 65.2%), while nymphs and larvae only accounted for 12.7% (20) and 22.2% (35), respectively. Only 7 A. testudinarium were collected from the wild boar (6 adults) and Eurasian badger (1 nymph), while only 5 I. nipponensis were collected from the water deer (4 adults) and a raccoon dog (1 adult). One adult female H. formosensis was first collected from vegetation by tick drag from Mara Island, Seogwipo-si, Jeju-do Province.

• Journal of the Mineralogical Society of Korea
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• v.16 no.3
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• pp.201-213
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• 2003

The adsorption property and ability of domestic zeolites for some heavy metal ions (Ag, Pb, Cr, Cu, Zn, Mn), which may cause a serious environmental problem in industrial wastewater, were evaluated on ore unit through a series of adsorption experiments together with careful examinations of mineral composition and properties of the zeolites. Though the adsorption behavior basically took place in the form of a cation exchange reaction, the higher CEC value does not necessarily to imply the higher adsorption capacity for a specific heavy metal. A general trend of the adsorption selectivity for heavy metals in the zeolites is determined to be as follow: $Ag\geq$Pb>Cr,Cu$\geq$Zn>Mn, but the adsorption properties of heavy metal ions somewhat depend on the species and composition of zeolite. Clinoptilolite tends to adsorb selectively Cu in case of Cr and Cu, whereas heulandite prefers Cr to Cu. A dominant adsorption selectivity of the zeolite ores for Ag and Pb is generally conspicuous regardless of their zeolite species and composition. The zeolite ores exhibit a preferential adsorption especially for $Ag^{+}$ so as not to regenerate when treated with $Na^{+}$ . In the adsorption capacity for heavy meta ions, the zeolites differ in great depending on their species: ferrierite>clinoptilolite>heulandite. Considering the CEC value of mordenite, the mordenite-rich ore appears to be similar to the clinoptilolite ore in the adsorption capacity. The adsorption capacity for heavy metals is not positively proportional to the CEC values of the zeolites measured by the exchange reaction with ammonium ion. In addition, the adsorption capacity roughly tends to depend on the zeolite contents, i.e., the grade of zeolite ore, but the trend is not consistent at all in some ores. These may be caused by the adsorption selectivity for some specific heavy metals, the presence of possible stacking micro-faults and natural cations such as K hardly to exchange in the zeolite. Considering the economic availability and functional effectiveness as natural zeolite resources, clinoptilolite ores could be applicable to utilize the domestic zeolites for the removal of heavy metals.