• Journal of Life Science
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• v.22 no.6
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• pp.788-793
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• 2012

High concentration of antibiotics has been used to treat the outbreak of edwardsiellosis caused by Edwardsiella tarda in aquaculture. However, not all of the bacteria have been killed with high concentrations of antibiotics treatment by the formation of persister cells with a dormant state. The main objective of this study was to kill persister cell using antibiotics with the addition of natural plant compounds. Antibiotics used in this study consist of 100 mg/ml florfenicol and 100 mg/ml amoxicillin. Ten natural plant compounds with persister cell inhibitor activity to E. coli were obtained from Protein Engineering and Systems Biology Lab. of Sungkyunkwan University. The persister cell inhibition activities of those natural plant compounds were evaluated in test tube. Concentrations of the antibiotics were in the ranges of 25~200 ${\mu}g/ml$. The persister cell formation was observed after 16 hours of culture. Persister cells were killed by antibiotics with natural plant compounds. Among ten natural plant compounds, Gynostemma pentaphyllum, Mallotus japonicus, and Orixa japonica showed persister cell formation inhibition activities. The optimal concentrations of G. pentaphyllum, M. japonicus, and O. japonica for the inhibitor of persister cell formation were 100 ${\mu}g/ml$, 100 ${\mu}g/ml$, and 200 ${\mu}g/ml$, respectively. In vivo study was carried out to evaluate the effect of the antibiotics with natural plant compounds using aquacultural fish, olive flounder, as test animals. G. pentaphyllum, M. japonicus, and O. japonica of 30 ${\mu}g/ml$, 10 ${\mu}g/ml$, and 10 ${\mu}g/ml$ with antibiotics reduced cumulative mortalities, showing the effectiveness of persister cell inhibition.

• Journal of the Mineralogical Society of Korea
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• v.28 no.2
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• pp.95-108
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• 2015

Nano-sized iron colloids are formed as acid mine drainage is exposed to surface environments and is introduced into surrounding water bodies. These iron nanomaterials invoke aesthetic contamination as well as adverse effects on aqueous ecosystems. In order to control them, the characteristics of their behaviour should be understood first, but the cumulative research outputs up to now are much less than the expected. Using zero-valent iron (ZVI) and magnetite, this study aims to investigate the behaviour of iron nanomaterials according to the change in the composition and pH of background electrolyte and the concentration of natural organic matter (NOM). The size and surface zeta potential of iron nanomaterials were measured using dynamic light scattering. Characteristic behaviour, such as aggregation and dispersion was compared each other based on the DLVO (Derjaguin, Landau, Verwey, and Overbeek) theory. Whereas iron nanomaterials showed a strong tendency of aggregation at the pH near point of zero charge (PZC) due to electrostatic attraction between particles, their dispersions became dominant at the pH which was higher or lower than PZC. In addition, the behaviour of iron nanomaterials was likely to be more significantly influenced by cations than anions in the electrolyte solutions. Particularly, it was observed that divalent cation influenced more effectively than monovalent cation in electrostatic attraction and repulsion between particles. It was also confirmed that the NOM enhanced the dispersion nanomaterials with increasing the negative charge of nanomaterials by coating on their surface. Under identical conditions, ZVI aggregated more easily than magnetite, and which would be attributed to the lower stability and larger reactivity of ZVI.

• Reproductive and Developmental Biology
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• v.34 no.3
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• pp.247-252
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• 2010

This study was carried out between 2008 and 2009 in four dairy farms to investigate the effect of feeding of whole crop barley silage on the reproductive performance of Holstein heifers. Two diets, mixed hay or whole crop barley silage separately from concentrate were fed 6-month old Holstein heifers (=37). In control group (=CON), heifers (n=16) were fed 6 kg (/head) mixed hay and 4 kg (/head) commercial diet. In whole crop barley silage group (=WBS), heifers (n=21) were fed 10 kg (/head) whole crop barley silage, 4 kg (/head) mixed hay and 2 kg (/head) commercial diet. To manage body weight gain, the body condition score of heifers were measured every month. The results obtained were as follows: 1. Body weight in CON and WBS heifers at 13-, 14-, 15- and 17-month old were $340{\pm}17.9$ and $342{\pm}13.6\;kg$, $356{\pm}15.7$ and $366{\pm}14.7\;kg$, $382{\pm}13.1$ and $387{\pm}14.4\;kg$, and $429{\pm}15.0$ and $417{\pm}10.3\;kg$, respectively. 2. Body condition score in CON and WBS heifers at 9-, 12-, 15- and 17-month old were $2.88{\pm}0.04$ and $2.80{\pm}0.04$, $2.88{\pm}0.04$ and $2.80{\pm}0.04$, $2.89{\pm}0.08$ and $3.00{\pm}0.07$, and $2.89{\pm}0.08$ and $3.00{\pm}0.07$, respectively. 3. Average age of sexual maturity in CON and WBS heifers were $437.3{\pm}9.9$days and $939.6{\pm}12.5$days, WBS group heifers were significantly shorter (p<0.05) than CON group heifers. 4. First-service conception rates in CON or WBS group were 81.3% (13/16) and 66.7% (14121), respectively, and cumulative conception rate to 2nd artificial insemination were 87.5% for CON and 85.7% for WBS group. Conception rate was not different between treatments.

• Korean journal of applied entomology
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• v.49 no.3
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• pp.199-204
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• 2010

The seasonal fluctuation of the large 28-spotted lady beetle, Henosepilachna vigintioctomaculata (Motschulsky), was observed in potato fields of Gangneung region, Gangwondo Province. The effects of their leaf consumption over a 24 hour period and developmental periods by different temperatures were investigated, and then the developmental threshold (DT) and effective cumulative temperature (ET) of each stage were calculated. Various developmental stages of H. vigintioctomaculata were captured in the fields from May to September, with three peaks in late May, late June, and late August. Leaf consumption by larval stages increased with the development of instar. The 4th instar larvae consumed potato leaves much more than other stages. Egg hatchability and emergence rate of H. vigintioctomaculata were lower at $10^{\circ}C$ and $30^{\circ}C$, but higher at around $20{\sim}23^{\circ}C$. The developmental periods of each stage became shorter as temperature increased; 90 days at $10^{\circ}C$, 40 days at $20^{\circ}C$ and 25 days at $25^{\circ}C$. Base on developmental velocity to temperature, calculated DT and ET were $7.3^{\circ}C$ and 83.

• Women's Health Nursing
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• v.1 no.2
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• pp.174-199
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• 1995

This study examined the antenatal care known as Taekyo. The sample consisted of 795 women and 564 men who had be seen in the antenatal care unit, delivery room, or postpartal care unit of general hospitals in Korea between March 20 and April 22, 1995. Data were collected using the "Taekyo questionnaire for childbearing women" and "Taekyo questionnaire for husbands of childbearing women" developed by researchers. Data were self-reported. Data were analyzed using the SPSS PC+ program, and descriptive statistics, T-test, ANOVA, Pearson correlation coefficient were applied. The results of this study were as follows : 1. Encouragement to practice Taekyo was at a relatively high level. Items on Taekyo encouraging behaviors had a mean score of 3.51(33 items 5 point scale). According to the five categories of Taekyo encouraging behaviors, subjects indicated they practice "food intake(mean score 4.02)". "praying(mean score 3.78)", "cumulative virtuous deeds (mean score 3.58)". "mind and body management(mean score 3.47)", "maternal fetal interaction(mean score 3.15)". 2. The childbearing women's practices related to forbidden behaviors by Taekyo were relatively high. Item on forbidden behaviors by Taekyo had a mean score 3.71(43 items 5 point scale). According to the five categories of forbidden behaviors by Taekyo, subjects indicated they practiced "voluntary abstention of drugs(mean score 4.78)," avoiding behaviors(mean score 4.78)," avoiding behaviors(mean score 3.77), "good behaviors(mean score 3.71)", "taboo on fetal death tendency (mean score 3.53)", "taboo on certain intake(mean score 3.47)". 3. The practice score of husbands for childbearing women which related to Taekyo behaviors were relatively high. Item on Taekyo behaviors had a mean score 3.59(33 items 5 point scale). According to the six categories of Taekyo behavior, subjects indicated they practiced "mind and body management(mean score 3.94)", "praying(mean score 3.80)", "support of women’s practice related to Taekyo(mean score 3.66)", "good behaviors(mean score 3.58)", "continency(mean score 3.33)", "paternal fetal interaction (mean score 3.19)". 4. On the childbearing women's perception of Taekyo, most of the subjects(88%) had confidence in the positive effects of Taekyo on Child development. The result showed that the childbearing couples practiced Taekyo behavior relatively often and sincerely and most of the childbearing women had a positive perception of Taekyo's effect on prenatal child development.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.269-278
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• 2020

In this study, the effects of groundwater artificial recharge through vertical wells in the upper small basin are preliminarily evaluated by using field injection test and a 3-D numerical model. The injection rate per well in a model is set to 20, 37.5, 60, and 75 ㎥/day based on the results of field injection test, groundwater levels, and hydraulic conductivities estimated from particle size analysis, and a numerical model using MODFLOW is conducted for 28 cases, which have diverse injection intervals, in order to estimated the changes of groundwater level and water balance after injection. Groundwater level after injection does not show a linear relationship with the injection rate per well, and the cumulative effect of artificial recharge decreases and the timing of maximum water level rise is shortened as the injection interval becomes longer. In four cases of continuous injection with total injection rate of 1,200 ㎥, it is revealed that the recharge effect is analyzed as 36.5~65.3% of the original injection rate. However, it will be more effective if the artificial recharge system combined with underground barrier is introduced for the longer pumping during a long and severe drought. Additionally, it will be possible to build a stable artificial recharge system by an establishment of efficient scenario from recharge to pumping as well as an optimization of recharge facilities.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1030-1035
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• 1998

The porous alumina membrane was prepared from aluminum metal(99.8%) by anodic oxidation using DC power supply of constant current mode in an aqueous solution of sulfuric acid. To prevent the chemical dissolution of alumina membrane, $Al_2(SO_4)_3$, $AlPO_4$ and $Al(NO_3)_3$ which could be considered to supply $Al^{3+}$ ions were added to electrolyte solution at a reaction temperature of $20^{\circ}C$ and cumulative charge of $150C/cm^2$. Effects of these additives on the formation of porous alumina membrane were evaluated under various electrolyte concentration(5~20 wt%) and current densities($10{\sim}50mA/cm^2$). The membrane surfaces which were prepared in electrolyte solution with all the additives except $Al_2(SO_4)_3$ were damaged. However, when $Al_2(SO_4)_3$ was added to the $H_2SO_4$ solution, an uniform surface of porous alumina was obtained. Also, it was shown that the pore size of membrane was nearly independent on the quantity of $Al_2(SO_4)_3$ added at same electrolyte concentration and current density.

• 한국무역상무학회:학술대회논문집
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• 2006.06a
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• pp.45-72
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• 2006

The Equator Principles are a set of voluntary environmental and social guidelines for ethical project finance. These principles commit banks and other signatories to not finance projects that fail to meet these guidelines. The principles were conceived in 2002 on an initiative of the International Finance Corporation and launched in 2003. Since then, dozens of major banks have adopted the Principles, and with these banks among them accounting for more than three quarters of all project loan market volume the Principles have become the de facto standard for all banks and investors on how to deal with potential social and environmental effects of projects to be financed. While regarding the Principles an important initiative, NGOs have criticised the Principles for not producing real changes in financing activities and for allowing projects to go through that should have been screened out by the Principles, such as the Sakhalin-II oil and gas project in Russia. In early 2006, a process of revision of the principles was begun. The Equator Principles state that endorsing banks will only provide loans directly to projects under the following circumstances: - The risk of the project is categorized in accordance with internal guidelines based upon the environmental and social screening criteria of the International Finance Corporation (IFC). - For all medium or high risk projects (Category A and B projects), sponsors complete an Environmental Assessment, the preparation of which must meet certain requirements and satisfactorily address key environmental and social issues. - The Environmental Assessment report addresses baseline environmental and social conditions, requirements under host country laws and regulations, applicable international treaties and agreements, sustainable development and use of renewable natural resources, protection of human health, cultural properties, and biodiversity, including endangered species and sensitive ecosystems, use of dangerous substances, major hazards, occupational health and safety, fire prevention and life safety, socio-economic impacts, land acquisition and land use, involuntary resettlement, impacts on indigenous peoples and communities, cumulative impacts of existing projects, the proposed project, and anticipated future projects, participation of affected parties in the design, review and implementation of the project, consideration of feasible environmentally and socially preferable alternatives, efficient production, delivery and use of energy, pollution prevention and waste minimization, pollution controls (liquid effluents and air emissions) and solid and chemical waste management. - Based on the Environmental Assessment, Equator banks then make agreements with their clients on how they mitigate, monitor and manage those risks through an 'Environmental Management Plan'. Compliance with the plan is required in the covenant. If the borrower doesn't comply with the agreed terms, the bank will take corrective action, which if unsuccessful, could ultimately result in the bank canceling the loan and demanding immediate repayment. - For risky projects, the borrower consults with stakeholders (NGO's and project affected groups) and provides them with information on the risks of the project. - If necessary, an expert is consulted. The Principles only apply to projects over 50 million US dollars, which, according to the Equator Principles website, represent 97% of the total market. In early 2006, the financial institutions behind the Principles launched stakeholder consultations and negotiations aimed at revising the principles. The draft revised principles were met with criticism from NGO stakeholders, who in a joint position paper argued that the draft fails by ignoring the most serious critiques of the principles: a lack of consistent and rigorous implementation.

• The Korean Journal of Pain
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• v.11 no.2
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• pp.241-246
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• 1998

Background: Opioids and local anesthetics have been administered epidurally for the purpose of the postoperative analgesia. However opioids have a serious risk of respiratory depression and local anesthetics have the risks of hypotension, sensory block, or motor one. In recent years, reports of spinal administration of midazolam for acute postoperative pain control have appeared in the literature. This study was performed to observe the effect of epidural midazolam in patient-controlled analgesia (PCA) device. Methods: Forty-five patients scheduled for the elective total hysterectomy were randomly selected; epidurally take morphine only (group I, n=15), morphine plus 0.1% bupivacaine (group II, n=15), or morphine plus midazolam (group III, n=15). The visual analogue scale (VAS) at rest and with movement, the sedation score, the degree of the satisfaction, the total amounts of a morphine usage, and the incidence of the side effects were observed. Rusults: The VAS at rest of group II and III were decreased significantly than that of group I. The VAS with movement of group III was significantly decreased than that of group I and II. The sadation score and the cumulative dose of a morphine were statistically insignificant within groups. Conclusion: Epidural morphine plus midazolam was proven to be clinically effective in the post-operative pain control especially for the pain with movement, compared with epidural morphine only and morphine plus 0.1% bupivacaine.

• Journal of the Korean Regional Science Association
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• v.31 no.4
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• pp.47-69
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• 2015

The purpose of this study is to analyze regional spatial distribution and characteristics with the Talent Magnet Potential Index(TMPI), which is calculated through the extra-regional talent attracting environment(Magnet factors) and intra-regional talent cultivating environment(Incubator factors) of each region. As a result, Seoul, Daejeon, Gyeonggi, Ulsan etc. ranked highest, and regions developed in knowledge-based services, R&D capability, and manufacturing turned out to have a higher TMPI. The regions were categorized into 4 types, and the regional type analysis showed that the cumulative effects of Type I(Talent comparative advantage type) and Type III(Talent absolute shortage type) contribute to widening the economic gap among these regions. In addition, although the metropolitan based Type IV(intra-regional talent dependant type) had excellent talent training capability, there seemed to be an outflow of talent into Type I or Type II(extra-regional talent dependant type). This paper has done a correlation analysis to test the validity of the TMPI. As a result, the correlation between talent by type and TMPI turned out to be very high. The correlation coefficient with 2T turned out to have the highest correlation, showing that tolerance contributes a much greater deal to talent attracting and training than expected. Finally, based on the main analytical results, implications for talent attraction & training policy projects and 7 improvement plans have been proposed.