• The Journal of the Korean Society for Microbiology
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• v.22 no.1
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• pp.79-93
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• 1987

The result of various researches mainly in search of 194 Shigella strains, isolated by the Health Research Centers(situated in Seoul city, Inchon city, Pusan city, Kyonggi-Do, Kangwon-Do, Chungchongnam and Buk-Do, Kyongsangnam and Buk-Do, Jollanam and Buk-Do, and Jaeju-Do) in addition to those clinical laboratories of all the general hospitals situated down twon Seoul, conducted during the month of Jan. through Dec. 85, through the reisolating-activity program following its transportation into the laboratory, particularly for a complete check on its correctiveness, are as follows: 1. Isolation processes were performed with the 194 strains obtained from each placeduring the period of investigation: 164 Strains(84.5%) of Sh. flexneri, B group; 6 Strains(3.1%) of Sh. boydii, C group; 24 Strains(12.3%) of Sh. sonnei, D group, which means there's quite a lot in B group while Sh. dysenteriae, A group was not isolated at all. 2. The isolation rate of the 164, B group for subserotype was 1b, 84(51.2%) the highest one, 2(1.2%) on 3a the lowest one, 4, on C group; In D group subserotype II showed 14(58.4%) more than subserotype I. 3. The biological data on sexuality regarding the isolation-strain showed traditional particularity. But the subserotype 1b in B group 2(2.4%) showed gas-growth from glucose. In subserotype 1a, the indole-growth was 88.9% on masculine which was considerably a good one. In the test of arginine dihydrolase subserotype I among D group showed 100% masculine rate. The subserotype 6 among B group showed 92.5% masculine. In the dissolution test of manitol, all subserotypes showed 100% maculine except subserotype 1b. In the dissolutioning test of rhamnose, the subserotype I among D group showed 100% masculine which is the unusual one. 4. Interms of the area among 13 districts examined, Kangwon-Do had 41(21.1%) which is the highest one on its ratio. 5. In terms of season on the strain isolation category, 44(22.7%) is the number isolated in April which is the highest one. 6. In terms of ages, the strain isolation ratio was notably high above the ages of 60 which was 34(17.5%). Next one was 29(14.9%) which was under the ages of 4. 7. In terms of sex, female was 113 or 58.2% while male was 74 or 38.2%, which means the female had more than the male. 8. The result of the resisting capability on the usage of 12 antibiotic medication was; 100% on chloramphenicol; 94.3% on tetracycline, 82.0% on streptomycin, 76.3% on carbenicillin, 74.7% on ampicillin, in regular order. The strain source bearing multimedication resisivity against the 5 antibiotic medication is as many as 117 or 60.3%. Of which 43.3% of 1b sub serotype, B group was the best one, and thus the resistivity against the antistrain medication seems the tendency is being changed. The summing up of the above result shows the total specific strains isolated in each branch in Korea is 194, of which the main type is Sh. flexneri 84.5%. The isolating rate is almost evenly spreading, although the Kangwon-Do showed the highest rate on the above data. It also shows female is higher than male on its statistics. The tendency on age category showed both on old and infancy generations high. However, the resistant capability against antibacteria medication or vaccine was still remaining on habitual one, particularly tending towards multimedication or vaccine trend.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.75-86
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• 2003

In the near future, the capacity of conventional anaerobic digester is thought to be insufficient because of the increase of the total solids from expansion of intercepting sewer, sewage quantity and direct input of night soil from near apartment districts. The objectives of this study was to investigate the improvement of digestion efficiency using microbial agent(Bio-dh). The system was a pilot-scale, two-staged, anaerobic sludge digestion system. The first-stage digester was heated and mixed. The agitation velocity of the first-stage digester was 120rpm. The second-stage digester was neither heated nor mixed. The Digestion temperature was kept at $35{\pm}1^{\circ}C$ The detention time of digester was 19 days. The dosage of sewage sludge and microbial agent were $0.65m^3/day$ and $0.5{\ell}/day$, respectively. The experiments was run for 25days. Three times a week, $COD_{Mn}$ and SS of effluent, TS, VS, and biogas production rate were measured. Temperature, pH, and alkalinity were measured daily. The results were as follows ; Without microbial agent, digestion efficiencies ranged 46.0%~50.9%(mean=48.6%), with microbial agent(Bio-dh), digestion efficiencies ranged 52.8%~57.3%(mean=54.2%). Consequently, microbial agent(Bio-dh) increased the sludge digestion efficiency about 12%. Also, Without microbial agent, the mean concentration of $COD_{Mn}$ and SS of second-stage digester effluent were 1,639mg/L, 4,888mg/L respectively. With microbial agent, the mean concentration of $COD_{Mn}$ and SS of second-stage digester effluent were 859mg/L, 2,405mg/L respectively. Consequently, microbial agent(Bio-dh) increased the removal efficiency of $COD_{Mn}$ and SS about 47.6% and 50.8%, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.7
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• pp.514-520
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• 2014

In this study, the production potential of alternative coagulant ($Al_2(SO_4)_3$ solution) having the identical coagulation activity with respect to the commercial coagulant was investigated. The raw material of alternative coagulant was a spent catalyst including aluminium (waste activated alumina) generated in the manufacturing process of the polymer. The alternative coagulant was produced through a series of processes: 1) intense heat and grinding, 2) chemical polymerization and substitution with $H_2SO_4$ solution, 3) dissolution and dilution and 4) settling and separation. To determine the optimal operating conditions in the lab-scale autoclave and dissolver, the content of $Al_2O_3$ in alternative coagulant was analyzed according to changes of the purity of sulfuric acid, reaction temperature, injection ratio of sulfuric acid and water in the dissolver. The results showed that the alternative coagulant having the $Al_2O_3$ content of 7~8% was produced under the optimal conditions such as $H_2SO_4$ purity of 50%, reaction temperature of $120^{\circ}C$, injection ratio of $H_2SO_4$ of 5 times and injection ratio of water of 2.3 times in dissolver. In order to evaluate the coagulation activity of the alternative coagulant, the Jar-test was conducted to the effluent in aerobic reactor. As a result, in both cases of Al/P mole of 1.5 and 2.0, the coagulation activity of the alternative coagulant was higher than that of the existing commercial coagulant. When the production costs were compared between the alternative and commercial coagulant through economic analysis, the production cost reduction of about 50% was available in the case of the alternative coagulant. In addition, it was identified that the alternative coagulant could be applied at field wastewater treatment plant without environmental problem through ecological toxicity testing.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.121-130
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• 1985

The phenolic compounds identified from rye and wheat residues seemed to be p-coumaric, p-hydroxybenzoic, vanillic, ferulic, salicylic and syringic acids. Total phenol content of rye and wheat straw determined at heading stage was 0.1803% and 0.1702%, respectively. Total phenol content in straw was higher than that of root at all growth stages. The germination and growth of plants, such as Oryza sativa, Echinochloa creugalli, Cyperus serotinus, Portulaca oleacea, Amaranthus retroflexus, Digitaria saguinalis, and C. album were inhibited by treatments of authentic phenolic compounds as the concentrations increased. However, at the early stage, the germination and shoot growth of P. distinctus were markedly stimulated by them, and then the further growth of shoot and root was markedly inhibited by the prolonged treatment of phenolic compounds. The aqueous extracts from rye and wheat straw completely inhibited the germination of A. retroflexus and C. album at a high concentrations. The content of starch and protein in bulbs of P. distinctus was lower in the p-hydroxybenzoic acid treated plot, at $10^{-2}M$, than the untreated control.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.238-245
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• 1998

The reasonable level of nitrogen fertilizer is a key factor to reduce environmental contamination as well as to increase crop yield and quality. The treatments are $N=42kg\;10a^{-1}$, $N=48kg\;10a^{-1}$, $N=54kg\;10a^{-1}$. $N=60kg\;10a^{-1}$. $N=72kg\;10a^{-1}$ and $N=150kg\;10a^{-1}$. Analytical results of yield and quality of tea leaves harvested the second time are summarized as follows: The soil of experimental field was higher in organic matter($49.9g\;kg^{-1}$) and available phosphate($937mg\;kg^{-1}$) compared to the general field but lower in pH(5.07) compared to the general field. When the amount of nitrogen fertilizer application was raised, the yield of tea leaves, the content of nitrogen, total free amino acids, caffeine and chlorophyll increased: however, the yield of tea leaves increased to excessive levels. On the other hand, the increased level of nitrogen fertilizer did not show any difference in the contents of vitamin C and tannin. Eleven kinds of amino acids were isolated from second harvested leaves of tea where the content of theanine occupied over 50%, and content of $665{\sim}763mg\;100g^{-1}$. The contents of fatty acids and catechin did not show correlation with application level of nitrogen fertilizer. The content of fatty acid was produced $1,742{\sim}2,643mg\;100g^{-1}$, and content of catechin was produced 12.47~13.54%. In scoring test, $N=60kg\;10a^{-1}$ treatment was 0.5~6.0 point higher compared to other treatments. Consequently, $N=60kg\;10a^{-1}$ is considered to be the best level of nitrogen fertilizer in terms of decreased environmental contamination as well as to increase crop yield and quality.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.99-106
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• 2013

The purpose of this study is to investigate the effects of supplementation of mulberry powder, mulberry extract and silkworm powder during the 8 weeks of resistance exercise on Androgen receptor(AR) mRNA and Myogenic regulatory factors(MRFs) expression of rats muscle. Fifty males, Sprague-Dawley rat, were randomly divided into 5 groups: CON(control group, n = 10), REG(resistance exercise group, n = 10), MP REG(mulberry powder intake and resistance exercise group, n = 10), ME REG(mulberry extract intake and resistance exercise group, n = 10) and SP REG(silkworm powder intake and resistance exercise group, n = 10). After climbing the ladder without weights during the 1 week of adaptation period, the rats in the resistance exercise group were trained to climb a 0.98-m vertical(80 degree incline) ladder with weights in their tail during 7 weeks(10 times each day, 2 days per week). After exercise, the skeletal muscle was extracted from the flexor hallucis longus. After separating the total ribonucleic acid (RNA) of each group, quantitative polymerase chain reaction was used to analyze RNA quantitatively. AR mRNA and MRFs expression revealed that all of the treated groups had significantly difference. AR mRNA expression increased in ME REG $6.24{\pm}1.85$ and SP REG $9.68{\pm}0.28$ fold compared to CON. Myod mRNA expression increased in MP REG $6.04{\pm}0.47$, ME REG $4.31{\pm}1.58$ and SP REG $8.11{\pm}0.57$ fold compared to CON. And myogenin mRNA expression increased in MP REG $4.11{\pm}0.42$, ME REG $4.12{\pm}0.45$ and SP REG $6.50{\pm}0.61$ fold compared to CON. In conclusion, during the resistance exercise, providing mulberry and silkworm gives positive effect on AR mRNA and MRFs expression increase.

• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.235-247
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• 2012

Peridotite xenoliths hosted by alkali basalts from South Korea occur in Baengnyeong Island, Jeju Island, Boeun, Asan, Pyeongtaek and Ganseong areas. K-Ar whole-rock ages of the basaltic rocks range from 0.1 to 18.9 Ma. The peridotites are dominantly lherzolites and magnesian harzburgites, and the constituent minerals are Fo-rich olivine ($Fo_{88.4-92.0}$), En-rich orthopyroxene, Di-rich clinopyroxene, and Cr-rich spinel (Cr# = 7.8-53.6). Hydrous minerals, such as pargasite and phlogopite, or garnet have not been reported yet. The Korean peridotites are residues after variable degree of partial melting (up to 26%) and melt extraction from fertile MORB mantle. However, some samples (usually refractory harzburgites) exhibit metasomatic enrichment of the highly incompatible elements, such as LREE. Equilibration temperatures estimated using two-pyroxene geothermometry range from ca. 850 to $1050^{\circ}C$. Sr and Nd isotopic compositions in clinopyroxene separates from the Korean peridotites show trends between depleted MORB-like mantle (DMM) and bulk silicate earth (BSE), which can be explained by secondary metasomatic overprinting of a precursor time-integrated depleted mantle. The Korean peridotite clinopyroxenes define mixing trends between DMM and EM2 end members on Sr-Pb and Nd-Pb isotopic correlation diagrams, without any corresponding changes in the basement. This is contrary to what we observe in late Cenozoic intraplate volcanism in East Asia which shows two distinct mantle sources such as a DMM-EM1 array for NE China including Baengnyeong Island and a DMM-EM2 array for Southeast Asia including Jeju Island. This observation suggests the existence of large-scale two distinct mantle domains in the shallow asthenosphere beneath East Asia. The Re-Os model ages on Korean peridotites indicate that they have been isolated from convecting mantle between ca. 1.8 and 1.9 Ga.

• Korean Journal of Microbiology
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• v.43 no.4
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• pp.325-330
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• 2007

RNase E is an essential Escherichia coli endoribonuclease that plays a major role in the decay and processing of a large fraction of RNAs in the cell and expression of N-terminal domain consisted of 1-498 amino acids (N-Rne) is sufficient to support normal cellular growth. By utilizing these properties of RNase E, we developed a genetic system to screen for amino acid substitutions in the catalytic domain of the protein (N-Rne) that lead to various phenotypes. Using this system, we identified three kinds of mutants. A mutant N-Rne containing amino acid substitution in the S1 domain (I6T) of the protein was not able to support survival of E. coli cells, and another mutant N-Rne with amino acid substitution at the position 488 (R488C) in the small domain enabled N-Rne to have an elevated ribonucleolytic activity, while amino acid substitution in the DNase I domain (N305D) only enabled N-Rne to support survival of E. roli cells when the mutant N-Rne was over-expressed. Analysis of copy number of ColEl-type plasmid revealed that effects of amino acid substitution on the ability of N-Rne to support cellular growth stemmed from their differential effects on the ribonucleolytic activity of N-Rne in the cell. These results imply that the genetic system developed in this study can be used to isolate mutant RNase E with various phenotypes, which would help to unveil a functional role of each subdomain of the protein in the regulation of RNA stability in E. coli.

• Journal of dental hygiene science
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• v.7 no.1
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• pp.1-7
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• 2007

This study aimed to provide basic information on dental hygienists' practicing the prevention of infections by figuring out their actual conditions in dental clinics. The subjects of the study were the dental hygienists who participated in the continuing medical education of Incheon & Gyeonggi-do association and Seoul city association in October and November 2005 and the self-administered surveys were used for the prevention of infections. The results were as below. 1. In terms of education experiences of infection prevention, those who answered "there were" were 72 persons (42.9%) and those who followed the educational route for infection prevention were "through the in-house education from the hospital" and they were 42 persons (58%), which were highest. 2. In terms of the injury experiences, those who answered "there were" were 147 persons (87.5%) and the number of annual injury out of 147 persons with injury experiences was 7.7 time. For the tools that were damaged, 125 persons (75%) damaged the "explorer," which was highest. 3. For the experiences of being infected with contagious diseases, those who answered "there were" were 6 persons (3.6%) and there were four persons for "hepatitis B", one person for "rubella" and one person for "TB." 4. The questions with high practice scores were as in the following: "2. I wash my hands after conducting medical examinations (1.86 points)," "7. I always close the lid of a shot of Novocain after doing local anesthesia (1.86 points)" and "20. I separate and collect the wastes and give them to those who treat accumulated materials (1.85 points)". Meanwhile, the questions with low practice scores were as below: "16. I change my medical gowns (doctor wears) once a day (0.24 point)" and "I wash my medical gowns every time after examining patients with contagious diseases (0.52 points)." 5. The question with high knowledge was as below: "1. The contagion during the dental treatment is determined by source of infection, infection methods, infection routes and the host that is prone to infection (0.95 point)" and the question with the lowest knowledge was "5. HBV(hepatitis B) is destroyed after adding 95oC of heat for more than 5 minutes (0.27 points)." 6. The question with the highest organization-related factors was "I am always ready to use a mask, gloves, etc. if necessary" (0.89 points)" and the question with the lowest score was "There is a guideline that I can refer when I am exposed to dangerous situations related to the contagion in my workplace (0.33 point)." 7. In terms of the equipment conditions of protectors in medical environments, 168 persons for (disposable) mask (100%), 167 persons for disposable gloves (Latex) (99.4%), which meant that most of them were equipped with them. On the contrary, 108 persons (64.3%) are equipped with the protectors for frontal faces, which is the lowest and 165 persons (98.2%) said that they had autoclave in their disinfecting and sterilizing devices.

• Journal of fish pathology
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• v.7 no.2
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• pp.161-171
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• 1994

In order to elucidate the outbreak mechanisms of a new disease which is characterized by an intense congestion in central venus sinuses(CVS) of gill filaments in cultured eel. these experiments were carried out; epidemically surveyed on the cultured eel farms in the vicinity of Kunsan city and experimentaliy outbreaked the disease in the stressful condition such as thermal and handling shock and innoculated the supernatant from the homogenate of naturally severe congested gill into eels and onto the monolayer of the CHSE-214. Although the frequency of congestion in eels of B, C, D and E farms were higher than in eels of A farms, the water qualities(stocked and cultured water) among farms were not a great difference. In eels of B, C, D and E farms, the values of haematocrit(Ht), haemoglobin(Hb), total protein(Tp), albumin(Alb), glucose(Glu), magnesium(Mg) were lower and the values of calcium(Ca), methemoglobin(Met-Hb), glutamic pyruvic transminase(GPT), glutamic oxalacetic transminase(GOT) higher than in eels of A farms. These valules have not related to the frequency of congestion. An intensive congestion and dilataton in CVS of gill filaments in experimentally handling-stressed eels produced similar histopathological changes to those observed in the spontaneously diseased eel, but not in eels experimentally injected with filtering contents. The cytopathic effect on the CHSE-214 was not observed. In stressed eels the congestion of gill was increased in relation to either the decrease ranges of water temperature or the incerase in accllimated times. And increase in Ht, Met-Hb, Alb, Glu, GOT and GPT and decrease in Mg, Hb and Tp were found, which had a close relationship to congestion of gill. Cortisol were increased according to the decrease ranges in acclimated water temperature. From these results, decrease in water temperature during selection placed eels upon the stressed condition, made increase in ionic strength in blood stream, and CVS was dilatated owing to the increased blood inflow.