• Title/Summary/Keyword: Long-term incubation

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Development of Estimation Indices for Refractory Organic Matter in the Han-River Basin using Organic Matter Parameters and Spectroscopic Characteristics (일반 유기물 항목과 분광특성을 이용한 한강수계 내 난분해성 물질 지표 제시)

  • Lee, Bomi;Lee, Tae-Hwan;Hur, Jin
    • Journal of Korean Society on Water Environment
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    • v.27 no.5
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    • pp.625-633
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    • 2011
  • A long-term water quality monitoring in the Han River Basin reveals a consistent increasing trend for the concentration of refractory organic matter (R-OM) in major monitoring sites of the watershed. Because the determination of R-OM concentrations typically requires a long time of microbial incubation, it is essential to present the estimation indices for R-OM for an efficient watershed management. In this study, a number of surface water samples were classified into three groups, each of which were collected from Lake Paldang, rivers at rain and non-rain events, respectively. The corresponding R-OM concentrations were correlated with biochemical oxygen demand (BOD), chemical oxygen demand (COD), and total organic carbon (TOC) concentrations as well as ultraviolet and fluorescence intensities of the filtered samples. Among the traditional organic matter parameters, TOC exhibited the highest correlation coefficient with the R-OM concentrations regardless of the types of the sample groups. The equations for conversing TOC into R-OM concentrations were finally suggested as $0.43{\times}TOC+1.12$, $0.44{\times}TOC+0.61$, $0.24{\times}TOC+1.28$ for river samples at rain and non-rain events, and lake samples, respectively. TOC-BOD(C), the values of the TOC concentrations subtracted by carbon-converted BOD concentrations, was a good index for estimating the absolute concentrations of R-OM. UV absorbance at 254 nm was well correlated with R-OM concentrations of river samples while fluorescence intensities at 350 nm showed an excellent relationship with R-OM concentration of the lake samples. Our results suggests that simple spectroscopic parameters could be applied for in-situ monitoring tool techniques in watersheds.

Antihypertensive Effects of Casein Hydrolysate in Spontaneously Hypertensive Rats (자연발증고혈압쥐에서 카제인 가수분해물의 혈압강하효과)

  • Kim, H.S.;In, Y.M.;Jeong, S.G.;Ham, J.S.
    • Journal of Animal Science and Technology
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    • v.44 no.4
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    • pp.483-490
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    • 2002
  • The aim of this study was to determine if a low-molecular weight casein hydrolysate has an anti- hypertensive effect in spontaneously hypertensive rats (SHR). Prior to the in vivo experiment, the casein hydrolysate was confirmed to be resistant to gastrointestinal digestion by confirming the retention of its potency as an inhibitor of angiotensin I-concerting enzyme after incubation with pepsin, trypsin, or chymotrypsin. The in vivo anti-hypertensive effect of the hydrolysate was determined by the tail cuff method. Following an oral administration of the hydrolysate solution, the systolic blood pressure (SBP) decreased by 12.9% (-28.9mmHg; P<0.05) at 3 h after the administration at a dose of 500mg/kg body weight. When the hydrolysate was administered as an emulsion with 30% egg yolk, its anti-hypertensive effect was even more greater at the same dose(-30.8mmHg or -15.9%; P<0.01). In a 50-day long-term trial where the casein hydrolysate was administered once a day, the SBP-lowering effect of the hydrolysate was apparent (P<0.05) from day 35 through the end. Moreover, organ weights and plasma glutamate oxaloacetate transaminase and glutamate pyruvate transaminase activities of the administered SHR were not significantly different from those of controls at the end of the long-term trial.

Influence of Long-term Fertilization on soil Enzymes Activity in Normal Paddy Soil (퇴비(堆肥) 및 비료(肥料) 장기연용(長期連用)이 토양내(土壤內) 효소활성(酵素活性)에 미치는 영향(影響))

  • Cho, Kang-Jin;Jung, Yeun-Tae;Choi, Jyung
    • Applied Biological Chemistry
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    • v.32 no.2
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    • pp.109-115
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    • 1989
  • This study was aimed to find out the influence of long-term fertilization for 21 years on soil enzyme activities in the silty clay loam textured normal paddy soil. Total urease activity (TUA) and the microbial urease activity (MUA) were shown to be changed significantly, but the accumulated urease activity (AUA) was similar within trial plots. Especially the MUA of the plots annually applied N.P.K. fertilizers with compost and N.P.K. fertilizers with silicate fertilizer were the highest among plots. The total L-glutaminase activity (TGA) and the accumulated L-glutaminase activity(AGA) were changed significantly among trial plots, but the microbial L-glutaminase activity (MGA) was not. By the simple correlation analysis, it was shown that the TGA and the AGA correlated highly significant to available phosphorus available $SiO_2$ content and pH. Addition of the toluene to the incubation mixture did not markedly affect the activity of phosphatase, but the difference of phosphatase activity among plots was significant. By the simple correlation analysis, it was shown that the phosphatase activity ; correlated highly significant to pH, available $SiO_2$, available phosphorus and exchangeable calcium in soils.

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Effects of Knowledge Management Activities on Transaction Satisfaction and Business Performance (지식전달체계가 거래만족과 사업성과에 미치는 영향)

  • LEE, Chang Won
    • The Korean Journal of Franchise Management
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    • v.12 no.4
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    • pp.1-11
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    • 2021
  • Purpose: The franchise system started by Singer Sewing Machine in the US is acting as a national economic growth engine in terms of job creation and economic growth. In China, the franchise system was introduced in the mid-1980s. And since joining the WTO, it has grown by 5-6% every year. However, compared to the growth rate of franchises, studies on shared growth between the chain headquarters and franchisees were insufficient. Accordingly, recent studies related to shared growth between the chain headquarters and franchisees have been active in China. The purpose of this study is to examine the knowledge transfer system between the knowledge creation, knowledge sharing, and the use of knowledge by franchise chain headquarters in China. In addition, the relationship between franchise satisfaction and performance is identified. Research design, data, and methodology: The data were collected from franchise stores in Sichuan, China, and were conducted with the help of ○○ Incubation, a Sichuan Province-certified incubator. From November 2020 to January 2021, 350 copies of the questionnaire were distributed in China, and 264 copies were returned. Of these, 44 copies with insincere answers and response errors were excluded, and 222 copies were used for analysis. The data were analyzed with SPSS 22.0 and AMOS 22.0 statistical packages. Result: The results of this study are as follows. First, knowledge creation has been shown to have a statistically significant impact on knowledge sharing and knowledge utilization. In particular, the effectiveness of knowledge creation was higher in knowledge sharing than in knowledge utilization. And we can see that knowledge sharing also has a statistically significant e ffect on knowledge utilization. Second, knowledge sharing was not significant for transaction satisfaction and business performance, and knowledge utilization was significant for transaction satisfaction and business performance. These results can be said to mean less interdependence of the Chinese franchise system. Finally, transaction satisfaction was statistically significant to business performance. The purpose of this study was to examine the importance of knowledge management to secure long-term competitive advantage for Chinese franchises. This study shows that knowledge sharing is important for long-term franchise growth. And we can see that there is a lack of knowledge sharing methods in the case of franchises in China. I n addition, it was found that the growth of Chinese franchises requires systematization of communication, information sharing measures and timing, help from chain headquarters, and mutual responsibility awareness.

Comparision of Preservation of Liquid Boar Semen between Lactose-Egg Yolk and $B\ddot{u}tschwiler$ Diluents (돼지 액상정액 보존을 위한 Lactose-Egg Yolk와 $B\ddot{u}tschwiler$ 희석액의 비교)

  • Park, C.S.;Cheon, Y.M.;Xu, Z.
    • Korean Journal of Animal Reproduction
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    • v.20 no.2
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    • pp.101-109
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    • 1996
  • This study was done to find out the methods of long-term use of liquid boar semen in 100 ml plastic bottle for artificial insemination and to investigate differences between Lactose-Egg yolk and Biitschwiler diluents according to storage temperature, and effect of final glycerol concent ration in Lactose-Egg yolk diluent. Liquid boar semen diluted with Lactose-Egg yolk diluent showed significantly higher sperm motility (p<0.05) after 0.5 and 2h incubation at 37$^{\circ}C$,than Butschwiler diluent at all storage length when it was preserved in the 5$^{\circ}C$ refrigerator. The NAR acrosome in Lactose-Egg yolk diluent a after 0.5 and 2h incubation at 37$^{\circ}C$, respectively, during preservation periods was similar to that in Biitschwiler diluent. When liquid boar semen was preserved at 15$^{\circ}C$, liquid boar semen in the Butschwiler diluent showed significantly higher percentages of sperm motility and NAR acrosome from third day to seventh than that in Lactose-Egg yolk diluent. In the effect of final glycerol concentration of liquid boar semen in the Lactose-Egg yolk diluent, the final glycerol concentration of 2% showed higer percentages of sperm motility and NAR acrosome than that of 0, 1, 3, and 5%. Farrowing rate, litter size and average pig weight at birth did not differ significantly between Lactose-Egg yolk and But schwiler diluents. As a result of this study, we found out that liquid boar semen can be stored for 6-7 days at 5$^{\circ}C$ in Lactose-Egg yolk diluent and at 15$^{\circ}C$ in Butschwiler diluent.

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Characterization of Bacillus polyfermenticus SCD for Oral Bacteriotherapy of Gastrointestinal Disorders (식품용 프로바이오틱 비스루트균의 주요 생균제 특성)

  • Paik, Hyun-Dong;Jung, Min-Yong;Jung, Hwang-Young;Kim, Won-Seok;Kim, Kee-Tae
    • Korean Journal of Food Science and Technology
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    • v.34 no.1
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    • pp.73-78
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    • 2002
  • Bacillus polyfermenticus SCD, which is commonly called as Bisroot strain, is being used for functional foods through the treatment of long-term intestinal disorders, since the live strains in the form of active endospores can successfully reach the target intestine in both humans and animals. The cells of B. polyfermenticus SCD were treated for 24 h in artifical bile after incubation for 2 h in artificial gastric juice and final number of the strain was reached to around $3.3{times}10^7\;CFU/mL$. In test of API ZYM kit, ${\beta}-glucuronidase$ or ${\beta}-glucosidase$ was not produced by B. polyfermenticus SCD. B. polyfermenticus SCD was resistant to antibiotics, such as nisin, streptomycin, tetracycline, and rifamycin. B. polyfermenticus SCD was also affected by alcohol concentration up to 4%, but more than 8%, their growth was not affected significantly. Finally, B. polyfermenticus SCD was shown to inhibit the growth of Listeria monocytogenes ATCC 19111 completely within 24 h of incubation, which indicated its bactericidal nature.

Isolation of Bacillus licheniformis Producing Antimicrobial Agents against Bacillus cereus and Its Properties (Bacillus cereus 증식 억제능을 가지는 Bacillus licheniformis SCK 121057의 분리 및 특징)

  • Kim, Yong-Sang;Yun, Suk-Hyun;Jeong, Do-Yeon;Hahn, Kum-Su;Uhm, Tai-Boong
    • Korean Journal of Microbiology
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    • v.46 no.3
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    • pp.270-277
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    • 2010
  • In order to manufacture Bacillus cereus-free fermented soybean products, an antimicrobial agentproducing isolate against B. cereus was obtained from 150 traditionally fermented soybean products. The morphological and biochemical tests and the phylogenetic relationship among 16S rRNA gene sequences indicated that the isolate named as the strain SCK 121057 was most closely related to Bacillus licheniformis. The B. licheniformis isolate began to produce the antimicrobial agent after 48 h of incubation. The agent was nonproteinaceous and insensitive to heat, long term storage and protease K. Electron microscopic observation indicated that the agent attacked the membrane of B. cereus, leaving the ghost cell. The isolate inhibited growth of B. subtilis, Lactobacillus brevis and various types of pathogenic strains including Escherichia coli, E. faecalis, Micrococcus luteus, Staphylococcus aureus, Aspergillus flavus, A. ochraceus, and A. parasiticus as well as B. cereus. After coinoculation of B. licheniformis SCK 121057 and B. cereus in the ratio (as the basis of CFU/g sample) of 10 to 1 on the surface of cooked soybeans, cell numbers of B. cereus had been dramatically reduced after 31 days of incubation compared to those of single inoculation of B. cereus.

Odorant Stimulation Promotes Survival of Rodent Olfactory Receptor Neurons via PI3K/Akt Activation and Bcl-2 Expression

  • Kim, So Yeun;Yoo, Seung-Jun;Ronnett, Gabriele V;Kim, Eun-Kyoung;Moon, Cheil
    • Molecules and Cells
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    • v.38 no.6
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    • pp.535-539
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    • 2015
  • Olfactory stimulation activates multiple signaling cascades in order to mediate activity-driven changes in gene expression that promote neuronal survival. To date, the mechanisms involved in activity-dependent olfactory neuronal survival have yet to be fully elucidated. In the current study, we observed that olfactory sensory stimulation, which caused neuronal activation, promoted activation of the phosphatidylinositol 3'-kinase (PI3K)/Akt pathway and the expression of Bcl-2, which were responsible for olfactory receptor neuron (ORN) survival. We demonstrated that Bcl-2 expression increased after odorant stimulation both in vivo and in vitro. We also showed that odorant stimulation activated Akt, and that Akt activation was completely blocked by incubation with both a PI3K inhibitor (LY294002) and Akt1 small interfering RNA. Moreover, blocking the PI3K/Akt pathway diminished the odorantinduced Bcl-2 expression, as well as the effects on odorant-induced ORN survival. A temporal difference was noted between the activation of Akt1 and the expression of Bcl-2 following odorant stimulation. Blocking the PI3K/Akt pathway did not affect ORN survival in the time range prior to the increase in Bcl-2 expression, implying that these two events, activation of the PI3K pathway and Bcl-2 induction, were tightly connected to promote post-translational ORN survival. Collectively, our results indicated that olfactory activity activated PI3K/Akt, induced Bcl-2, and promoted long term ORN survival as a result.

Long-Term Starvation Induces the Viable-but-Nonculturable Condition in Lactobacillus crispatus KLB46

  • Lee, Seok-Yong;Kim, Ju-Hyeon;Jang, Jeong-Eun;Kim, Seung-Cheol;Yun, Hyeon-Sik;So, Jae-Seong
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.918-922
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    • 2001
  • In a previous study, we have isolated a number of lactobacilli from Korean women, and one of them (KLB46) was identified as Lactobacillus crispatus by 16S rRNA gene sequencing. For the ecological treatment of bacterial vaginosis (BV) cell suspension of L. crispatus KLB46 was instillated into BV patients. L. crispatus KLB46 was found to persist for several days in cell suspension with no nutrients. In this study, in order to assess the influence of starvation on physiological activity, we compared the viability and culturability of KLB46 following suspension in various buffer solutions. A pair of in situ fluorescent dye was used to assess viability (i.e. membrane integrity) and the culturability was examined by plate count assay. A rapid epifluorescence staining method using the LIVE/DEAD Bacterial Viability Kit $(BacLight^{TM})$ was applied to estimate both viable and total counts of bacteria in cell suspension. $BacLight^{TM}$ is composed of two nucleic acid-binding stains ($SYTO\;9^{TM}$ and propidium iodide). $SYTO\;9^{TM}$ penetrates all bacterial membranes and stains the cells green while propidium iodide only penetrates cells with damaged membranes, therefore the combination of the two stains produces red fluorescing cells. Optimal staining conditions for $BacLight^{TM}$ were found to be with 0.0835M $SYTO\;9^{TM}$ and 0.05M propidium iodide for 15 min incubation at room temperature in dark. When cells were microscopically examined during 140 hours of starvation, the culturability decreased markedly while the viability remained relatively constant, which suggests that large fraction of KLB46 cells became viable but non-culturable (VBNC) upon starvation.

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SEG Based Engineering Education Innovation: A Case Study on GNTECH-ICEE

  • Bae, Kangyul;Jun, Geeill;Kim, Namkyung;Chung, Jaewoo;Cho, Yunjin;Huh, Keunyoung;Ki, Junghoon
    • Journal of Engineering Education Research
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    • v.15 no.5
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    • pp.69-77
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    • 2012
  • GNTECH-ICEE, which this study seeks to investigate and evaluate, demonstrates a new system of training innovative engineers. An essential component of this operation is a Small Engineering Group (SEG) that links professors, students and industrial experts together, to study and apply different techniques in determining the processes and products that relate industrial sectors needs. As an education program, SEG also provides a right direction for educating students, and generates industry-university link based human resources. Through these efforts, GNTECH-ICEE has effectively trained creative, professional, and practical engineers, by operating a variety of programs for meeting industrial needs and enhancing engineering education. SEG has many merits that have influenced its success so far, but the program also faces some challenges. The merits include; strong group bondage, practical ability incubation, and efficient administrative support. In terms of demerits, it is evident that sufficient theoretical education and local small-middle size enterprises (SMEs)' sustainable participation cannot be warranted. Thus, we propose that initiative strategies have been helpful to maximize GNTECH-ICEE's goal of making students into multi-player engineer, but continuously financial and administrative strategies be put into place in order to guarantee SMEs' long-term devotion to the program, and to help create a sustainable network between students and the companies involved.