• Environmental Analysis Health and Toxicology
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• v.19 no.1
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• pp.33-40
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• 2004

Benzoyl peroxide is a High Production Volume Chemical, which is produced about 1,371 tons/year in Korea as of 2001 survey. The substance is mainly used as initiators in polymerization, catalysts in the plastics industry, bleaching agents for flour and medication for acne vulgaris. In this study, Quantitative Structure-Activity Relationships (QSAR) are used for getting adequate information on the physical -chemical properties of this chemical. And hydrolysis in water, acute toxicity to aquatic and terrestrial organisms for benzoyl peroxide were studied. The physical -chemical properties of benzoyl peroxide were estimated as followed; vapor pressure=0.00929 Pa, Log $K_{ow}$ = 3.43, Henry's Law constant=3.54${\times}$10$^{-6}$ atm-㎥/mole at $25^{\circ}C$, the half-life of photodegradation=3 days and bioconcentration factor (BCF)=92. Hydrolysis half-life of benzoyl peroxide in water was 5.2 hr at pH 7 at $25^{\circ}C$ and according to the structure of this substance hydrolysis product was expected to benzoic acid. Benzoyl peroxide has toxic effects on the aquatic organisms. 72 hr-Er $C_{50}$ (growth rate) for algae was 0.44 mg/1.,48 hr-E $C_{50}$ for daphnia was 0.07mg/L and the 96hr-L $C_{50}$ of acute toxicity to fish was 0.24mg/L. Acute toxicity to terrestrial organisms (earth worm) of benzoyl peroxide was low (14 day-L $C_{50}$ = > 1,000 mg/kg). Although benzoyl peroxide is high toxic to aquatic organisms, the substance if not bioaccumulated because of the rapid removal by hydrolysis (half-life=5.2 hr at pH 7 at $25^{\circ}C$) and biodegradation (83% by BOD after 21 days). The toxicity observed is assumed to be due to benzoyl peroxide rather than benzoic acid, which shows much lower toxicity to aquatic organisms. One can assume that effects occur before hydrolysis takes place. From the acute toxicity value of algae, daphnia and fish, an assessment factor of 100 was used to determine the predicted no effect concentration (PNEC). The PNEC was calculated to be 0.7$\mu\textrm{g}$/L based on the 48 hr-E $C_{50}$ daphnia (0.07 mg/L). The substance shows high acute toxicity to aquatic organisms and some information indicates wide-dispersive ore of this substance. So this substance is, a candidate for further work, even if it hydrolysis rapidly and has a low bioaccumulation potential. This could lead to local concern for the aquatic environment and therefore environmental exposure assessment is recommended.

• Parasites, Hosts and Diseases
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• v.30 no.1
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• pp.25-32
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• 1992

Antigenic proteins of 36 and 29 kDa were localized in Spirometra mansoni plerocercoid (sparganum) immunohistochemically by avidin biotin complex (ABC) staining. When polyclonal antibodies such as BALB/c mouse serum immunized with crude saline extract of sparganum or confirmed sparganosis sera were reacted as pri-mary antibodies, the positive chromogen (3-amino, 9-ethylcarbazole) reactions were recognized at syncytial tegument, tegumental cells, muscle and parenchymal cells and lining cells of excretory canals. A monoclonal antibody(MAb) which was reacting to 36 and 29 kDa proteins in the extract of the worm was localized at the syncytial tegument and tegumental cells. The present results suggested that the potent antigenic proteins of 36 and 29 kDa in sparganum were produced at the tegumental cells and transported to the syncytial tegument.

• Parasites, Hosts and Diseases
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• v.31 no.2
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• pp.135-140
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• 1993

An experimental study was performed to observe the infectivlty of sparganum (plerocercold of Spirometra erinncel) treated by prazlquantel, gamma-irradiation and mechanical cutting. The spargana were obtained from the naturally Infected European grass snake, Rhabdophis tigrina, or from the expenmentally infected mice. A total of 83 mice (ICR straine were divided Into 3 experimental groups by the source of the damage, fed each UH 5 spargana, and sacnaced 1 month later for worm recovery. In the praziquantel group, the worms were incubated In the concentration of 10㎍/ml (control: Tyrode for 4 hours) for 0.5. 1.2 and 4 hours at 36℃. and fed to mice. The recovery rate from mice in prazlquantel group was not different from that (80%) of control poop and in the range of 76-100%. In the gamma-Irradiation group, the worms were irradiated by 10-1000 Gy with Csl37. The average recovery rates of 69-100% were not different from that of control up to 100 Gy. The rate was 56% under 150 Gy, and 5% by 1000 Gy. In the mechanical cutting group, the worms were cut at 0.5, 1, 2 and 3 m from the anterior end of the scolex. The average recovery rates In each group were 70-90% and that of control was 90%. The present folding suggests that the sparganum be highly resistant to prazlquantel, gamma- irradiation and mechanical cutting. The vitality center of the sparganum must be at the anterior end of Its scolex.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.21-26
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• 2014

Dirofilaria immitis (heartworm) infections affect domestic dogs, cats, and various wild mammals with increasing incidence in temperate and tropical areas. More sensitive antibody detection methodologies are required to diagnose asymptomatic dirofilariasis with low worm burdens. Applying current transcriptomic technologies would be useful to discover potential diagnostic markers for D. immitis infection. A filarial homologue of the mammalian translationally controlled tumor protein (TCTP) was initially identified by screening the assembled transcriptome of D. immitis (DiTCTP). A BLAST analysis suggested that the DiTCTP gene shared the highest similarity with TCTP from Loa loa at protein level (97%). A histidine-tagged recombinant DiTCTP protein (rDiTCTP) of 40 kDa expressed in Escherichia coli BL21 (DE3) showed immunoreactivity with serum from a dog experimentally infected with heartworms. Localization studies illustrated the ubiquitous presence of rDiTCTP protein in the lateral hypodermal chords, dorsal hypodermal chord, muscle, intestine, and uterus in female adult worms. Further studies on D. immitis-derived TCTP are warranted to assess whether this filarial protein could be used for a diagnostic purpose.

• Korean Journal of Veterinary Research
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• v.14 no.1
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• pp.59-71
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• 1974

The studies were conducted on the allergic skin reaction of bovine eurytremiasis. In order to confirm the appearance of allergic skin reaction in this disease, a protein fraction of Eurytrema SPP(EPF) was extracted, and it's antigenicity was studied by means of intradermal reaction on the rabbits, goats and bovine. Rabbits used in this studies were divided into three groups: the first group was sensitized with EPF, the second group was sensitized with EPF, and the third group was served as control which is consisted with 5 non-sensitized and 2 saline injected rabbits. Three healthy native goats and bovine also used. Among these, 86 cases were eurytremiasis, 31 cases were fascioliasis and 71 cases non-infected. A protein fraction was also made from adult worm of Fasciola SPP(FPF) and tested the cross reaction between these two different fluke infestations. The results obtained were as follow: 1. Intradermal reaction was appeared in the infected cattle(bovine eurytremiasis) as well as in the EPF sensitized rabbits and goats. 2. In the EPF sensitized rabbits, the wheal of the intradermal reaction reacted the maximum size (increased wheal size of 5.0 to 9.0 mm) in 40 to 60 minutes and erythema in 60 minutes after intradermal injection of EPF antigen. In the EPF sensitized goats, the size of wheal reacted the maximum(increased wheal size of 5.5 to 8.0 mm) in 30 to 40 minutes, and then disappeared in 120 to 180 minutes after injection of EPF antgen. On the contrary, in the control groups of rabbits and goats, the wheal (7.0 mm) produced following antigen injection reached only to 7.5 to 8.5 mm. in 10 minutes without developing erythema, and then perished in 40 to 60 minutes after injection of EPF antigen. In the infected cattle, the wheal of the intradermal reaction reached the maximal sizes(increased wheal size of 4.0 to 11.0 mm) in 15 to 20 minutes and perished in 60 to 90 minutes after injection of EPF antigen. 3. It would be standardized that the positive reaction is above 4.0 mm, the negative below 2.0 mm and the suspective is 3.0 mm of the infected cattle. In the results of intradermal reaction, 87.2%(75 of 86 cases) was positive, 4.7%(4 of 86 cases) negative and 8.1% (7 of 86 cases) was suspective. However, in the non-infected control cattle, the wheal produced following injection disappeared in 30 to 40 minutes without increasing the wheal size in the most subjects or with incresing only to 1.0 to 2.0 mm in a few cattle. 4. In the results of intradermal reaction which were reciprocally tested in EPF sensitized rabbits by FPF antigen and in FPF sensitized. rabbits by EPF antigen, there were cross reacted. In the 31 cases if fascioliasis tested by EPF antigen, 11 cases were not specifically reacted with EPF antigen. Judging from the results of cross reaction in experimental rabbits and natural bovine fascioliasis, it would be expected when both EPF and EPF antigens are given intracutaneously on the same bovine patients of eurytremiasis or fascioliasis, the former antigen will produce the larger wheal in eurytremiasis, while the latter antigen will produce also the larger wheal in fascioliasis.

• Parasites, Hosts and Diseases
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• v.27 no.3
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• pp.217-224
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• 1989

Four females and a male nematode isolated from 2 patients who visited eye clinics In Seoul were identified as Thelazia callipaeda and their ultrastructures were observed by scanning electron microscopy(SEM). General features of the worms were slender and attenuated at both ends. Vaginal opening was located at 0.27 mm from the anterior end, and in front of the esophagointestinal junction. In the body cuticle transverse striations varied characteristically through the body. The number of cuticular transverse striations was 400∼650/mm at head portion, 250/mm at middle portion and 300∼350/mm at tail portion. The SEM observation of the mouth part of the females showed 6 cord-like cuticular thickenings in hexagonal arrangement and an amphid was observed. A lateral line, a vaginal opening, a pair of phasmids, and an anus were identified in the body portion. A pair of papillae and 6 cord-like cuticular thickenings were on the mouth part of the male. It was difficult to observe structures at the tail of the male except wrinkle-like structures. Most of the larvae isolated from the uterus of a female worm were sheathed and thus cuticular striations were not Eren. Others were unsheathed and revealed cuticular striations. The oval membrane which encysted sheathed larvae was also observed. These are the 18th and 19th record of human thelaziasis in Korea as the literature are concerned.

• Parasites, Hosts and Diseases
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• v.35 no.1
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• pp.25-30
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• 1997

Gymnophclloides seoi is a human intestinal trematode prevalent on southwestern islands in Korea. In the present study, we investigated whether G. seoi metacercariae can grow and develop into adults by in vitro cultivation. The metacercariae were obtained from naturally infected oysters, and cultured in uitro for 5 days under three conditions; $37^{\circ}C/5%{\;}CO_2,{\;}41^{\circ}C/8%{\;}CO_2,{\;}or{\;}41^{\circ}C/15%{\;}CO_2$, in NCTC 109 complete media containing 20% FBS and 1% antibiotics-antimycotics. The degree of worm growth and development was compared with that grown in uiuo of C3H mice. The length of the worms cultivated in uitro was $200-300{\;}\mu\textrm{m}$, not significantly different from metacercariae, whereas the length of the worms recovered from C3H mice was significantly larger, $300-400{\;}\mu\textrm{m}$. The worms produced eggs when grown in C3H mice or cultured in vitro for 2 days under $41^{\circ}C/8%{\;}CO_2{\;}or{\;}41^{\circ}C/5%{\;}CO_2$, but not when cultured under 37$^{\circ}C/5%{\;}CO_2$. Among the in vitro conditions, $41^{\circ}C/15%{\;}CO_2$ was best for egg Production, although the number of eggs was about half of worms obtained from C3H mice. In conclusion, in vitro cultivation of G. semi metacercariae into egg-pioducing adults was partially successful under culture conditions of $41^{\circ}C/5%{\;}CO_2{\;}or{\;}41^{\circ}C/8%{\;}CO_2$.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.445-460
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• 2017

This study was carried out for three years from 2013 to 2015 to investigate the actual condition of pest control of domestic persimmon organically cultivated farmers, to select environment - friendly pest control materials for major pests, and to conduct field test of established control system. The main cultivated cultivar of the reader farmer of organic cultivation was "Buyou" and sprayed organic agricultural material 9~17 times per year for pest control. The most harmful pests were anthracnose, bugs, persimmon fruit worm, and scales, etc. The control materials used were organic lime sulfur mixture, red clay sulfur, emulsifier, bordeaux solution, and self-made plant extracts using garlic, ginkgo nut and pine tree. The effective materials for controlling anthrax were lime sulfur mixture and red clay sulfur. Garlic oil + citronella emulsion, shrubby sophora seed extract + tea extract was effective to control Riptortus clavatus and Euproctis subflava. When installed 60 ea per 10a of mating disruption trap in a sweet orchard, the fruit setting rate was improved by 30%. The results of field test of control system to control 10 times a year in organically grown persimmons were able to harvest fruit of 70.7%. However, since any kinds of pesticides can not be sprayed during the harvest season in September and October, the damaged by bugs did not decreased, and further research is needed.

• Journal of the Mineralogical Society of Korea
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• v.19 no.3 s.49
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• pp.129-138
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• 2006

In this study, we identified the secondary precipitates from Samsan-jeil and Sambong mine, Goseong, Gyeongnam by means of scanning electron microscopy, electron probe microanalysis and X-ray powder diffraction analysis. Copper sulfide minerals had been produced from the mines during last few decades, however they are not worked. White and blue precipitates were found at the downstream of mine rock dump at Sambong mine and green one was at Samsan-jeil mine. The white precipitate covered the host rock surface with thickness of $30{\mu}m$, and is a kind of diatom with $10{\mu}m$ in length and $3{\mu}m$ in width. It is a species Fragilaria constuens, which is contained a order Pennales(pennate diatom) and lives in fresh water. The blue precipitate is the alteration product of chalcopyrite. It resultes in the increase in the ratio Cu:Fe from 5 to 13. The green precipitate has worm-like morphology with $10{\sim}20nm$ in diameter and $200{\sim}300nm$ in length. It is mainly composed of secondary copper sulfate such as woodwardite. However, it could be formed by the activity of microorganism, because the copper content is more than any secondary copper sulfate reported in copper sulfide mine. In order to identity the green precipitate exactly, the further research is needed.

• Economic and Environmental Geology
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• v.15 no.1
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• pp.41-47
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• 1982

Typical stratigraphic sequences of Paleozoic form the Baegunsan Syncline (equal to Hambaeg Syncline) and Taebaegsan Group is the basement in the southern part of Kangweon Province. Deformation pattern depends on their stratigraphic site and their internal properties. In the biotite schists and meta-sandstones of Pre-Cambrian sequences, flow folds and ptygmatic folds are developed, and high strain deformation is pervasive. Deformational patterns of Cambro-Ordovician are variable because of their various formations. Fracturing is pervasive in the Jangsan Quartzite and Daegi and Maggol Limestone. Welldeveloped slaty cleavage and angular folds of kink and chevron types are the prevailing structures of pelitic rocks. The most characteristic feature of limestone alternated with argillite is the "Compositional cleavage (Author's proposal)" known as the "Worm-eatern" structures. It was known that this structures have a sedimentary origin. But their preferred orienation of long axis of erosional lime holes, originated from tectonic deformation of folding. And this structures have the same character as the axial plane cleavages. Fracturing and long wave concentric folds are dominant characters of the Upper Paleozic sequences. In this area, two folds are superimposed. Field studying and analysis of structures show that the cross-folds of NS-direction are pervasive and were deformed by the EW-directional Baegunsan Syncline. The cross-folding is the major and penetrative deformation and prior to Baegunsan Syncline.