• The Korean Journal of Zoology
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• v.16 no.2
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• pp.127-137
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• 1973

Monosodium glutamate(MSG) is a widely used food additive. Some reports descried its positive effect and the others, negative effect on mouse, monkey, human or drosophilid flies. Because of the conflicting reports the present investigation was undertaken to study the effects of MSG on the development of Drosophila melanogaster. The two strains of D. melanogaster, Oregon-R and Sinchon-I were used and MSG as well as cane sugar (as the second control) media were prepared by adding MSG or cane sugar at various concentrations to the standard food media for the present study. Ten flies (Male 5, Female 5) were placed in each vial and the numbers of $F_1$ flies emerged from it were counted. The results are presented below: 1. The numbers of $F_1$ flies decrease as the concentrations of MSG increase, implying that MSG has an inhibitory effect in the development of D. melanogaster. 2. The effects of cane sugar show an enhancing effect rather than an inhibitory one. 3. The numbers of $F_1$ fies produced in the Sinchon-I strain are greater than in the Oregon-R. This may be due to the difference in the length of inbred period. 4. The Muller-5 test shows a negative result, suggesting that MSG may be not mutagenic.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.505-518
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• 1997

The objective of this investigation was to compare the effects of water storage on the aspect of hardness and diametral tensile strengths of four hybrid glass ionomer cements(two compomers and two resin-reinforced glass ionomers) with a resin composite material. One composite resin(Degufill Ultra), two compomers(Dyract, Compoglass Cavifil), and two resin-reinforced glass ionomers(Fuji Duet, Vitremer) were used in this study. Cylindrical specimens were prepared and stored at $36{\pm}1^{\circ}C$ in distilled water for 10 minutes after set, and then tested on an Instron testing machine(No.4467) at 1.0 mm/min displacement rate. Vicker's hardness and diametral tensile strengths as time elapsed were measured after aging in water for 10 minutes, 1 hour, 3 hours, 1 day, 3 days, 5 days and 7 days at $36{\pm}1^{\circ}C$. During the test of diametral tensile strength, stress-strain curves were obtained, from which the compressive modulus were calculated and compared. The structure of four set glass ionomer cement mass was observed on SEM(Hitachi, S-2300) after being etched with 9.6% hydrofluoric acid for 1 minute. The results were as follows; 1. The hardness of the experimental group(compomer and the resin reinforced glass ionomer cement) did not exceed the value of control group(Degufill Ultra). 2. Vicker's hardness of the Fuji Duet tended to increase succeedingly, Dyract was decreased after 3 hours in water, and Vitremer was the lowest. 3. The control group(Degufill Ultra) presented progressively on increased diametral tensile strength with time, Fuji Duet were decreased after 3 days, Compoglass Cavifil and Vitremer were decreased after 5 days in water storage. 4. Compressive modulus of the control group(Degufill Ultra) and Dyract were increased sharply timely, Fuji Duet and Vitremer were increased smoothly by lapse of time in water. Fuji Duet were stronger than Vitremer. On the other hand, Vitremer exhibited the lowest toughness. 5. The microstructure of compomer was similar with that of the composite resin(Degufill Ultra), and the fillers in resin-reinforced glass ionomer cements were noticed. It can be concluded that mechanical properties of hybrid glass ionomer cements is weaker than composite resin, and that the compomers or the resin-reinforced glass ionomers can not substitute the composite resins. A plenty of considerations should be done on the application of them to the area under the loading and high wear has a little adverse effect on the mechanical properties on the water storage for 7 days. The further research should be needed to confirm the advantage of the compomer.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.177-186
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• 1990

To investigate the etiology, pathogenicity and virological properties of NYJ-1-87 strain of Aujeszky's disease virus (ADV) that was isolated from the diseased piglet in Korea, the virus at $10^{6.0}TCID_{50}/0.1ml$ was inoculated intranasally and subcutaneously into 30 to 35 days-old piglets. Results obtained through the experiments were summarized as follows. 1. Ten of the infected piglets were clinically observed for 15 days. On the 2nd day post-inoculation(pi), the signs of pyrexia, anorexia and convulsion were noted. On the 4th to 7th days pi, nervous signs of incoordination and intermittent spasm were shown in the most of piglets, and one out of 5 piglets infected intranasally was died with severe nervous signs at the 7th day pi. The signs became relieved on the 8th day pi and all of remainder were completely recovered on the 13th to 14th days pi. 2. In hematological study, prominent decrease in the number of total leukocyte and lymphocyte was shown in the ADV-infected piglets on the 6th day pi. On the 8th day pi, the cell numbers were slightly increased and returned to normal level on the 10th day pi. 3. Viral excretion of the ADV-inoculated piglets was examined by swabbing of nasal and oral cavities, and rectal feces. During the periods of the 3rd to 11th days pi, the virus was excreted intermittently from nasal and oral cavities, and rectal feces. The nasal excretions were shown the highest virus concentration of $10^{5.2}TCID_{50}/0.1ml$ at the 5th day pi. 4. Recovery of the inoculated virus from various organs of the piglets that were died or experimentally slaughtered was attempted, and the virus was isolated from the tissues of brain and tonsil by the cultured cell-inoculation method. The highest recovery rate was noted in the tonsil. By indirect immunofluorescence antibody assay using ADV-monoclonal antibody, the viral antigens were detected in tissues of spleen and liver as well as brain and tonsil on the 7th to 9th days pi. The virus was not isolated from blood and the tissues of lung and kidney throughout the experiments. 5. Titers of virus neutralizing antibody in the piglets experimentally infected with ADV became increased after the 6th to 9th days pi in both of intranasal and subcutaneous inoculation showing the highest titers of 64 to 128 on the 29th day pi. When the antibody levels were measured by radial immunodiffusion enzyme assay, the reactive diameter was enlarged to be positive after the 4th to 6th days pi in both of intranasal and subcutaneous inoculation showing the largest diameter of 13 to 14mm on the 29th day pi.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.17-22
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• 1999

The effect of microwave irradiation on wood bending was investigated in this study. The specimens irradiated with microwave were bent around a form by using pedestal-steel and clamps. The specimens, korea red pine (Pinus densiflora), for this test were water-soaked for 78 hours. Saturated specimens were boiled in water for an hour. The size of specimens was 350mm(L) by 20mm(R) by 10mm(T). These specimens were heated by microwave of 2,450MHz. The most suitable time for microwave irradiation seems to range from 60 to 90 seconds. Wood moisture content decreased remarkably with the increase of irradiation time. When a softened wood piece is bent, its convex side was stretched while the concave side was compressed. It can be compressed considerably, but stretched very little. Therefore the failure will be governed by the tensile breaking strain and occur mainly on the convex face. So we obtained results from three different bending process methods as follows : 1) When bending with a pedestal-steel, convex face had not tensile breakings, but concave face had compression fails. 2) When bending with a clamp, bending time increased more than pedestal-steel and occurred tensile breaking. 3) Bending with a pedestal-steel and a clamp was found to be the most excellent operation method in this study.

• Journal of Life Science
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• v.21 no.4
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• pp.554-560
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• 2011

This study was performed to investigate the effects of microbial augmentation on the biological treatment of paper mill wastewater. Three bacteria (KN11, KN13, KN27) capable of degrading aromatic compounds and a bacterial strain (GT21) producing an extracellular cellulase were isolated from soil and wastewater by selective enrichment culture. Through morphological, physiological, and biochemical taxonomies, isolated strains of KN11, KN13, KN27, and GT21 were identified as Acinetobacter sp., Neisseria sp., Bacillus sp., and Pseudomonas sp. and named Acinetobacter sp. KN11, Neisseria sp. KN13, Bacillus sp. KN27, and Pseudomonas sp. GT21, respectively. For analysis of non-biodegradable and chemical oxygen demand (COD)-increasing matter in a paper mill wastewater, we utilized GC/MS to detect aromatic compounds and their derivatives containing several substituted functional groups. The microbial augmentation, J30 formulated with the mixture of bacteria including Acinetobacter sp. KN11, Neisseria sp. KN13, Bacillus sp. KN27, and Pseudomonas sp. GT21, was used for the treatment of paper mill wastewater. The optimum temperature and pH for COD removal of the microbial augmentation, J30, were $30^{\circ}C$ and 7.5, respectively. For evaluation of the industrial applicability of the microbial augmentation, J30 in the pilot test, treatment efficiency was examined using paper mill wastewater. The microbial augmentation, J30, showed a COD removal rate of 87%. On the basis of the above results, we designed the wastewater treatment process of the activated sludge system.

• Journal of Life Science
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• v.26 no.10
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• pp.1202-1206
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• 2016

Unicellular cyanobacterial strains of Subsections I and II and filamentous cyanobacterial strains of Subsection III have been shown to be polyphyletic, heterocystous strains of Subsections IV and V, both of which were previously reported to be monophyletic. In this study, the small subunit ribosomal RNA (16S rRNA) sequences of 13 strains of cyanobacteria - one strain, Oscillatoria nigro-viridis PCC7112, of the Subsection III, 6 strains including genus Anabaena, Nostoc, Tolypothrix, Calothrix and Scytonema of the Subsection IV, and 6 strains including genus Hapalosiphon, Fischerella and Chlorogloeopsis of the Subsection V - were determined. The phylogenetic analysis of cyanobacteria was carried out using the 16S rRNA sequences. The results of the phylogenetic analyses of 16S rRNA sequences, based on Neighbour-joining, maximum-parsimony, and maximum-likelihood methods, indicated that the members of Subsection IV were not monophyletic but polyphyletic. In addition, the phylogenetic results strongly indicated that the genus Scytonema in Subsection IV could be a common ancestor of heterocystous cyanobacteria in Subsection IV and V. Furthermore, the phylogenetic analyses revealed that the genus Anabaena could be phylogenetically diverse and that cyanobacterial strains in Subsection IV might be polyphyletic, whereas those in Subsection V could be monophyletic, as reported before. The results for the genus Anabaena indicate that it should be reclassified.

• Korean Journal of Plant Resources
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• v.29 no.1
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• pp.26-31
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• 2016

Toxoplasmosis is an important cause of foodborne, inflammatory illnesses, as well as congenital abnormalities. Currently available therapies are ineffective for persistent chronic disease and congenital toxoplasmosis or have severe side effects which may result in life-threatening complications. There is an urgent need for safe and effective therapies to eliminate or treat this cosmopolitan infectious disease. The aim of this study was to investigate the in vitro anti-Toxoplasma activities of Plantago asiatica L., one of the herbal extracts, using tachyzoit of T. gondii RH strain infected HeLa cells. As the results, the selectivity of Plantago asiatica L. extract was 4.5, which was higher than Sulfadiazine selectivity (0.4). Also, we perfomed the cell proliferation inhibition test and the morphological study to evaluate the anti-T. gondii activity of Plantago asiatica L. extract with HeLa cells. As the results, the inhibition rate of the Plantago asiatica L. extract was high inhibition rate. This indicates that the Plantago asiatica L. extract may be used for new anti-T. gondii agent.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.4
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• pp.395-401
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• 2012

Purpose: The purpose of this study was to research any effect on vision protecting or decreasing VDT syndrome of extracted anthocyanine from fermented purple sweet potato and blueberry. Methods: Subjects were aged 19-20 years old who do not have ophthalmic and systemic diseases and over -N4.00 D of refraction error. 40 mg of extracted anthocyanine from fermented purple sweet potato, from blueberry, and control group, placebo were dosed at separate try. After 2 hours later, subjects were directed perform visual display terminal (VDT) work for 2 hours. Objective refractive error was measured before dosing anthocyanine and after VDT work for 2 hours. Degree of head ache, eye pain and strain and subjective symptoms of neck, shoulder and waist was also examined through interviews by dividing its degree into severe, moderate, slight or none. Results: After 2 hours VDT work, vision protection effect in terms of refractive error for dominant eye was decreased by $0.031{\pm}0.21$ D in the group of extracted anthocyanine from fermented purple sweet potato, $0.006{\pm}0.32$ D in the group of extracted anthocyanine from blueberry. However, there was significantly myopic progression in the placebo group by $0.144{\pm}0.28$ D (t=2.27, p=0.03). Conclusions: It is considered that extracted anthocyanine from fermented purple sweet potato inhibits increase of refraction anomalies of dominant eye rather than non-dominant eye after VDT work.

• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.195-199
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• 1998

AH alkalophilic Bacillus SP. AIk-7, isolated from soil, produced ethylene. The characteristics of this microorganism is the ability to grow well under the alkaline condition, at pH 10.3. This strain is similar to Bacillus alkalophilus in terms of morphological, physiological and biological characteristics. In observation of relationship of cell growth and ethylene production according to incubation times, the ethylene synthesis mostly occur from the late exponential phase to the death phase of growth. The purpose of this paper is to study the effects of various substrates on the biosynthesis of ethylene in the intact cell and the cell-free system by the Bacillus sp. AIk-7. In both intact cell and cell-free extract, optimum conditions for ethylene production was achieved at pH 10.3 and 3$0^{\circ}C$. Ethylene was effectively produced from L-Met and 1-aminocyclopropane-1-carboxylic acid (ACC). In this case, ACC as the substrate on ethylene production were two fold higher than L-met at each concentration of substrates. On the other hand, the cell-free ethylene-forming system was used as a tool for the elucidation of the biochemical reaction involved in the formation of ethylene by Bacillus sp. AIk-7. Ethylene production in the cell-free system required the presence of manganese and cobalt ion to be stimulated a little. The result obtained in this work suggests that L-met and ACC may be a precursor more directly related to bacterial ethylene production than any other substrates tested.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.5
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• pp.760-766
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• 1998

This study was carried out far isolation and characterization of ammonia oxidizing bacteria (AOB) from aquacultural place and sludges of waste water collected in Pusan. One autotrophic AOB, Nitrosomonas sp. and 8 heterotrophic AOB (2 strains of Bacillus sp., 2 strains of Acinetobacter sp., Xanthomonas sp., Alcaligenes sp., Pseudomonas sp., Sphingobacterium sp.) were isolated. and identified. Variation of total nmmonia nitrogen (TAN) and $NO_2-N$ in mineral salt media containing 10mg/ $\ell$ of NHCl for 15 days in differents 9 strains was measured in order to examine the ablitity of ammonia oxidation. TAN was started to reduce after 4 days incubation and ca. 2 mg/$\ell$ of TAN was decreased after 15 days incubation by Nitrosomonas sp., At that time, $NO_2-N$ was produced to 0.023$\~$0.036 mg/$\ell$. Heterotrophic AOB showed the low ability of ammonia oxidation, 0.02$\~$0,04 mg/$\ell$ of TAN was decreased and $NO_2-N$ was produced to 0.01$\~$0.51 mg/$\ell$ after 15 days. When each strain of 8 heterotrophs was incubated in mimeral salt media containing 10 mg/$\ell$ $NH_4Cl$ and 50 mg/$\ell$ glucose, and 50 mg/$\ell$ $NH_4Cl$ and 5 g/$\ell$ glucose, the diminution of TAN was 1.12$\~$3.38 mg/$\ell$ and 1$\~$20 mg/$\ell$, respectively.