• Journal of the Korean Electrochemical Society
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• v.21 no.2
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• pp.39-46
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• 2018

Many studies on the electrochemical performance of Li secondary batteries have been obtained using coin-type cells due to the ease of assembly, low cost and ensuring reproducibility. The coin-type cell consists of a case, a gasket, a spacer disk, and a wave spring. These structural features require a greater amount of liquid electrolyte to assemble than other types of cells such as laminated cells and cylindrical cells. Nevertheless, little research has been conducted on the effect of excess liquid electrolytes on the electrochemical performances of Li secondary batteries. In this study, we investigate the effect of different amounts of electrolyte on the coin-type cells. The amount of electrolytes is adjusted to 30 and $100mg\;mAh^{-1}$. Cycle performances at room temperature ($25^{\circ}C$) and high temperature ($60^{\circ}C$) and high voltage are performed to investigate the electrochemical properties of the different amount of electrolytes. In the case of the unit cell including the electrolyte of $30mg\;mAh^{-1}$, the discharging capacity retention characteristic is excellent in comparison with the case of $100mg\;mAh^{-1}$ under the high temperature and high voltage condition. The former shows a larger increase in internal resistance than the latter, confirming that the amount of electrolyte significantly influences the discharge capacity retention characteristics of the battery.

• Journal of Life Science
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• v.24 no.6
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• pp.700-706
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• 2014

Doxorubicin (trade name adriamycin), an anthracycline antibiotic, is commonly used in the treatment of a wide range of cancers, including hematological malignancies, many types of carcinoma, and soft tissue sarcomas. It is closely related to the natural product daunomycin, and like all anthracyclines, it works by intercalating DNA. Its most serious adverse effect is life-threatening heart damage. Its anti-metastatic mechanisms in human prostate carcinomas are not fully understood. In this study, we used LNCap human prostate carcinoma cells to investigate the inhibitory effects of doxorubicin on cell motility and invasion, two critical cellular processes that are often deregulated during metastasis. Doxorubicin treatment inhibited cell migration and invasiveness of LNCap cells without showing any toxicity. Doxorubicin treatment also suppressed the activity and expression of matrix metalloproteinase (MMP)-2 and MMP-9, which were associated with up-regulated expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 in LNCap cells. Doxorubicin treatment also attenuated the expression levels of claudin family members (claudin-1, -2,-3 and -4), major components of tightening of tight junctions (TJs) and increased the tightening of TJs, as demonstrated by an increase in transepithelial electrical resistance. The present findings demonstrate that doxorubicin reduces the migration and invasion of prostate carcinomas LNCap cells by modulating the activity of TJs and MMPs.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.349-354
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• 2000

Abstract A facultative alkalophilic gram-negative Vibrio metschnikovii strain RH530, isolated from the wastewater, produced several alkaline proteases (VAP) including six alkaline serine proteases and a metalloprotease. From this strain, high yielding YAP mutants were isolated by NTG treatment. The isolated mutant KS1 showed nine times more activity than the wild-type after optimization of the culture media. The production was regulated by catabolite repression when glucose was added to the medium. The effects of several organic nitrogen sources on the production of the YAP were investigated to avoid catabolite repression. The combination of 4% wheat gluten meal (WGM), 1.5% cotton seed flour (eSF), and 5% soybean meal (SBM) resulted in the best production when supplemented with 1% NaCl. The YAP showed a resistance to surfactants such as $sodium-{\alpha}-olefin$ sulfonate (AOS), polyoxy ethylene oxide (POE), and sodium dodecyl sulfate (SDS), yet not to linear alkylbenzene sulfonate (LAS). However, the activity of the YAP was restored completely when incubated with LAS in the presence of POE or $Na_2SO_4$. The YAP was stable in a liquid laundry detergent containing 6.6% SLES (sodium lauryl ether sulfate), 6.6% LAS, 19.8% POE, and stabilizing agents for more than two weeks at $40^{\circ}C$, but the stability was sharply decreased even after 1 day when incubated at $60^{\circ}C$. A washing performance test with the YAP exhibited it to be a good washing power by showing 51 % and 60% activity at $25^{\circ}C{\;}and{\;}40^{\circ}C$, respectively, thereby indicating that the YAP also has a good detergency at a low temperature. All the results suggest that the YAP produced from the mutant strain KSI has suitable properties for use in laundry detergents.rgents.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4885-4890
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• 2015

Background: Helicobacter pylori plays an important role in gastric cancer and typical eradication regimens are no longer effective in many countries, including Thailand. The aim of our study was to compare the effect of Lactobacillus delbrueckii and Streptococcus thermophillus on tailored triple therapy for Helicobacter pylori eradication. Materials and Methods: This prospective single-center study was conducted in Thailand. Helicobacter pylori associated gastritis patients were randomized to 2 groups: group 1 (n=100) was tailored triple therapy with placebo (esomeprazole 20 mg bid, clarithromycin 500 mg bid or metronidazole 400 mg tid if clarithromycin resistance and amoxicillin 1000 mg bid), and group 2 was tailored triple therapy plus pretreatment with probiotic containing yogurt. Successful eradication was defined as both negative histology and negative rapid urease test at four weeks after treatment. Results: A total of 200 infected patients were enrolled. PP analysis involved 194 patients: 96 in the tailored triple therapy with placebo group (group 1) and 98 the in tailored triple therapy plus pretreatment with probiotic containing yogurt group (group 2). Successful eradication was observed in 170 (87.6%) patients; by PP analysis, the eradication rate was significantly higher in group 2 (P = 0.04, 95%CI; 0.02-0.13) than in group 1. ITT analysis also showed that the value was significantly higher in the tailored triple threapy plus pretreatment with probiotic containing yogurt group (group 2) (89/100; 89%) than in the tailored triple therapy with placebo group (group 1) (P= 0.01, 95%CI; 0.04-0.15). In terms of adverse events, there was no significant difference between the two groups. Conclusions: Pretreatment with probiotic containing yogurt can improve Helicobacter pylori eradication rates with tailored triple therapy. Adding probiotics does not reduce adverse effects of the medication.

• Annals of Geriatric Medicine and Research
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• v.22 no.4
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• pp.167-175
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• 2018

Sarcopenia, a common clinical syndrome in older adults, is defined as decreased muscle mass, strength, and physical performance. Since sarcopenia is associated with the incidence of functional decline, falls, and even mortality in older adults, researchers and health care providers have been keen to accumulate clinical evidence to advocate the screening and prevention of sarcopenia progression in older adults. The factors that may accelerate the loss of muscle mass and function include chronic diseases, inactivity, and deficiency in appropriate nutritional support. Among these, nutritional support is considered an initial step to delay the progression of muscle wasting and improve physical performance in community-dwelling older adults. However, a nationwide study suggested that most Korean older adults do not consume sufficient dietary protein to maintain their muscle mass. Furthermore, considering age-associated anabolic resistance to dietary protein, higher protein intake should be emphasized in older adults than in younger people. To develop a dietary protein recommendation for older adults in Korea, we reviewed the relevant literature, including interventional studies from Korea. From these, we recommend that older adults consume at least 1.2 g of protein per kg of body weight per day (g/kg/day) to delay the progression of muscle wasting. The amount we recommend (1.2 g/kg/day) is 31.4% higher than the previously suggested recommended daily allowance (i.e., 0.91 g/kg/day) for the general population of Korea. Also, evidence to date suggests that the combination of exercise and nutritional support may enhance the beneficial effects of protein intake in older adults in Korea. We found that the current studies are insufficient to build population-based guidelines for older adults, and we call for further researches in Korea.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.2
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• pp.122-129
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• 2014

Objectives: Because of its properties such as resistance to heat, chemicals and corrosion; tensile strength; sound absorption; and affordable price, asbestos has been widely used as a building material, fire resistant and retardant, thermal and heat insulator, soundproofing material, and electrical insulation. Since the prolonged inhalation of asbestos can cause serious illnesses such as lung cancer, mesothelioma, and asbestosis after an incubation period of 20 to 40 years, the mineral was classified as a Group 1 carcinogen by the International Agency for Research on Cancer, an intergovernmental agency forming part of the World Health Organization. Children and infants are more at risk than are adults if they are exposed to carcinogens, due to aweaker immunity that has not yet been fully developed. Most childcare centers are operated all day and children tend to spend a great amount of time in the centers. This is why it is important for them to be systematically isolated from environments that may expose them to asbestos. Materials: In order to understand both indoor and outdoor hazards to which children may have been exposed, the study focused on actual surveys of asbestos used in childcare centers, paying special attention to slate-roofed buildings in the vicinity of the centers. Results: A survey of a total of 211 childcare centers showed that the buildings of 18.1% of the centers contained asbestos, with 60.53% of the material being found in classroom ceilings. "Tex" was the most used material for ceilings, making up 89.47% of all ceilings. An outdoor survey showed that childcare centers in Daegu Metropolitan City had an average of 143 slate-roof buildings within a distance of 1km. Conclusions: Buildings housing mainly toddlers, children, teenagers and others more vulnerable to the toxicity of asbestos are not subject to asbestos investigation by law. A legal and practical basis for asbestos control is required for such buildings. In particular, housing materials which contain asbestos in day care centers require asbestos control. GIS should be used to identify the location of buildings with slate roofing materials in the vicinity of daycare centers in order to gauge toxicity of exposure to asbestos caused by potential asbestos friability possibility in outdoor conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.9
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• pp.1236-1243
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• 2010

The aim of this study was to screen lactic acid bacteria for the fermentation of garlic and to assess the increase in inhibitory activity of garlic fermented against antibiotic-resistant pathogens for use as an animal feed supplement. We screened 45 strains of lactobacillus for the fermentation of garlic. Of these strains, 23 showed similar growth rates with or without allicin. Cultures of the 23 strains were mixed with an equivalent amount of garlic juice and incubated overnight at $37^{\circ}C$. The three strains with the lowest pH values were Lactobacillus paracasei KCTC 3169, L5 strain, and L. reuteri SW. Garlic juice fermented by the L5 strain more strongly inhibited antibiotic-resistant pathogenic bacteria than L. paracasei KCTC 3169, L. reuteri SW, or garlic juice itself. By examining carbohydrate utilization, morphologic properties and 16S rRNA gene sequences, we identified the L5 strain as Pediococcus pentosaceus and deposited it in the name of P. pentosaceus KACC 91419 into the Korea Agricultural Culture Collection. To identify the antimicrobial compound from the garlic filtrate fermented by P. pentosaceus KACC 91419, we fractionated P. pentosaceus KACC 91419 culture on a C18 column and checked the antimicrobial activity of fractions A6 to A10. Only fraction A9 showed inhibitory activity on Staphylococcus aureus. Comparing the mass spectra of the fractions with and without antimicrobial activity, we observed a single dominant product ion (m/z 157.99) from the fraction showing antimicrobial activity. Its molecular mass (157.99) was 2 atomic mass units less than that of allicin (162.02). This suggests that allicin might be converted to its derivative, which has antimicrobial activity, during fermentation by P. pentosaceus KACC 91419.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1167-1174
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• 2013

Cancer cells exhibit increased demand for glutamine-derived carbons to support anabolic processes. Indeed, the spectrum of glutamine-dependent tumors and the mechanisms through which glutamine supports cancer metabolism remain areas of active investigation. In the present study, we investigated the effects of glutamine deprivation on the correlation between tightening of tight junctions (TJs) and anti-invasive activity in human prostate carcinoma LnCap cells. Glutamine deprivation markedly inhibited cell motility and invasiveness in a time-dependent manner. The anti-invasive activity of glutamine deprivation was associated with an increased tightness of the TJ, which was demonstrated by an increase in transepithelial electrical resistance (TER). The activities of matrix metalloproteinase (MMP)-2 and MMP-9 were inhibited in a time-dependent fashion by glutamine deprivation, which was correlated with a decrease in expression of their mRNA and proteins and up-regulation of tissue inhibitors of metalloproteinases (TIMPs) expression. Furthermore, glutamine deprivation repressed the levels of the claudin family members, which are major components of TJs that play a key role in the control and selectivity of paracellular transport. Moreover, the levels of E-cadherin, a type I transmembrane glycoprotein, and snail, an epithelial to mesenchymal transition regulator and zinc finger transcription factor, were markedly modulated by glutamine deprivation. Taken together, these findings suggest that TJs and MMPs are critical targets of glutamine deprivation-induced anti-invasion in human prostate carcinoma LnCap cells.

• Journal of Engineering Education Research
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• v.22 no.6
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• pp.51-63
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• 2019

This study aims to present concept of "gong" which was shared by traditional East Asian societies (Korea, China and Japan) and to identify how it has been developed through their respective process of modernization and industrialization. Despite the territorial proximity of the three countries, their industrial and technological development followed different patterns, and the notion of engineering from the Occident was also accepted and reconstructed with a certain difference in each country. Japan had developed its own concept of engineering as part of industrialization in Western style and in the context of establishment of an imperialist nation. What was important for Japan was how engineering could contribute to the national development of technology and industry, and to the development of Imperial Japan. For China, which attached importance to resistance to Western civilizations and to strengthening the competitiveness for and which needed to resolve domestic political conflicts, engineering constituted more than a simple issue on technological and industrial dimension; it was also associated with obtaining ethical and political legitimacy which would allow the nation to gain support from the working and peasant classes. Though belated, Korean attempted to build an independent modern state, yet experienced a considerable nuisance from the invasion of Japan and the protracted colonial period. Engineering of Korea had to take a long time before emerging from backwardness especially because of Japanese policies which tended to restrict technological development and avoid fostering qualified engineers in the colony. Therefore, engineering in Korea started to contribute to the nation's development and the improvement of technological competitiveness only after it was combined with modern higher education after liberation, under the name of engineering science (工學, gong-hak). This study argues that our recognition of what engineering was for and who engineers were in East Asia will allow us to evaluate current status of engineering education and provide us with significant insight which will be useful when we imagine the future society. Identity of engineering in Korea, China, and Japan has been developed along with historical contexts such as clash of civilizations, wars, recovery of sovereignty and obtaining of national competitiveness; now, what will be combined with engineering in the next generation? This question will lead and motivate engineering students to think and imagine about what future engineering should be and how they respond to it.

• Food Science and Preservation
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• v.14 no.4
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• pp.369-377
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• 2007

This study investigated the effect of ginseng products on the baking properties of white breads. Flour was substituted by ginseng products (ginseng at levels 2, 4, 6, and 8%, all w/w, of flour levels). Both ginseng powder (GP) and red ginseng powder (RGP) were used. Similarly, red ginseng extract (RGE) was substituted at levels of 1, 2, 3, and 4% (all w/w) of flour. The physical properties of each dough were assessed using farinograms, extensograms, and amylograms. Water absorption increased as the proportions of ginseng products rose. The dough surface areas and R/E (resistance/extensibility) values decreased, as did peak viscosities, at the proportions of ginseng products increased. The pH values during fermentation decreased as the proportions of ginseng products increased. The fermentation power of dough with GP was lower than that of control, and higher than that of dough with RGP or RGE, but the addition of ginseng products beyond certain levels weakened the gas retention power: The specific loaf volumes of breads with 2% GP were the highest at 5.41 mL/g. In breads with RGE, the specificloaf volume increased from 5.52 mL/g to 5.82 mL/g as RGE levels rose from 0% to 4%. Hardness increased with rising GP and RGP levels in breads with GP and RGP, but decreased with RGE levels in breads with RGE. The moisture contents of breads during storage tended to be higher than control in breads with ginseng products. Lightness increased with addition of GP and decreased upon addition of RGP or RGE, while redness and yellowness increased after addition of any ginseng products. In sensory evaluation tests, the sensory scores for texture, color, mouth feel, and overall acceptability, were high, when any ginseng product (GP, RGP or RGE) was present at 2%. Of these breads, the bread with 2% RGE attained the highest sensory score.