• Journal of the Korean Ceramic Society
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• v.52 no.5
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• pp.308-314
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• 2015

The electrochemical performance and Cr poisoning behavior of $La_{1-x}Ba_xCo_{0.9}Fe_{0.1}O_{3-{\delta}}$ (LBCF, x = 0.3, 0.4, 0.5) and $La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_{3-{\delta}}$ (LSCF) cathodes were investigated for solid oxide fuel cells (SOFCs). The polarization resistance of the LBCF/GDC/LBCF symmetrical cell was found to decrease with increasing Ba content (x value). This phenomenon might be associated with the high oxygen vacancy concentration in the LBCF sample, with x = 0.5. In addition, there was no chromium poisoning in the LBCF cathode. On the other hand, the polarization resistance of the LSCF cathode was found to significantly increase after exposure to gaseous chromium species; it appears that this result stemmed from the formation of $SrCrO_4$ phase. Therefore, it can be expected that LBCF can be a durable potential cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFC).

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.3
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• pp.119-123
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• 2013

Simplified control logic was devised to fabricate and operate the modified atmosphere (MA) container of fresh produce equipped with gas-diffusion tube whose opening/closing was controlled in response to real time $O_2$ concentration. This is a simplified ramification of the previously developed control logic using both $O_2$ and $CO_2$ concentrations ([$O_2$] & [$CO_2$]). The developed logic was applied to and tested by a container system filled with spinach at $10^{\circ}C$ having optimum MA window of [$O_2$] of 7~10% and [$CO_2$] of 5~10%. It was shown that setting the proper on-off limit (11%) for $O_2$ control based on the assumed relationship $[O_2]+[CO_2]$=21% could attain the desired $CO_2$ concentration just below the upper tolerance limit ($[CO_2]_H$, 10%). The $O_2$ control point can be the lower tolerance limit or adjusted one (21-$[CO_2]_H$) depending on the commodity's MA requirement. The developed logic using single $O_2$ sensor could attain the equilibrated [$O_2$] of 11% with [$CO_2$] of 8~9% which was desired and similar to that of its predecessor ([$O_2$] of 9~10% with [$CO_2$] of 10%) using both $O_2$ and $CO_2$ sensors. Both MA containers (one only with single $O_2$ sensor control and one with $O_2$ and $CO_2$ sensors) could also keep the spinach quality without significant difference between them, but significantly better than perforated control package of air.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.311-319
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• 2011

Overusing chemical fertilizers involves potassium accumulation in the soil, which can become a toxicity problem in agriculture. This study was conducted to investigate the effect of potassium (K) treatment on growth, physiological characteristics, and morphological changes using Chinese cabbage (Brassica rapa L. ssp. campestris). With high (600 mM) K treatment, the plant growth traits of leaf length, leaf area, and fresh and dry weight of shoots and roots decreased, whereas chlorophyll content increased. As the concentration of K increasing, total N, P, and K increased in leaves, but concentrations of Ca, Mg, and Na decreased. However, Mn, Fe and Zn contents were highest in 100 mM K treatment. Chlorophyll a, b, and carotenoids increased with increasing K concentration. Maximum photochemical efficiency ($F_v/F_m$) was not significant in the all treatments, whereas $CO_2$ assimilation decreased with increasing K level due to stomatal degradation. Total free amino acids increased with the 10 and 100 mM K but decreased at 600 mM K treatments. Therefore, the growth and physiological characteristics of Chinese cabbage ascertained that tolerance up to 100 mM K when grown with nutrient solution in pot culture.

• Plant Biotechnology Reports
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• v.4 no.3
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• pp.213-222
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• 2010

Within their natural habitat, crops are often subjected to drought and heat stress, which suppress crop growth and decrease crop production. Causing overaccumulation of glycinebetaine (GB) has been used to enhance the crop yield under stress. Here, we investigated the response of wheat (Triticum aestivum L.) photosynthesis to drought, heat stress and their combination with a transgenic wheat line (T6) overaccumulating GB and its wild-type (WT) Shi4185. Drought stress (DS) was imposed by controlling irrigation until the relative water content (RWC) of the flag leaves decreased to between 78 and 82%. Heat stress (HS) was applied by exposing wheat plants to $40^{\circ}C$ for 4 h. A combination of drought and heat stress was applied by subjecting the drought-stressed plants to a heat stress as above. The results indicated that all stresses decreased photosynthesis, but the combination of drought and heat stress exacerbated the negative effects on photosynthesis more than exposure to drought or heat stress alone. Drought stress decreased the transpiration rate (Tr), stomatal conductance (Gs) and intercellular $CO_2$ concentration (Ci), while heat stress increased all of these; the deprivation of water was greater under drought stress than heat stress, but heat stress decreased the antioxidant enzyme activity to a greater extent. Overaccumulated GB could alleviate the decrease of photosynthesis caused by all stresses tested. These suggest that GB induces an increase of osmotic adjustments for drought tolerance, while its improvement of the antioxidative defense system including antioxidative enzymes and antioxidants may be more important for heat tolerance.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.111-111
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• 2017

The development and productivity of maize (Zea mays L.) is frequently impacted by water scarcity, and consequently to increased drought tolerance in a priority target in maize breeding programs. To elucidate the molecular mechanisms of resistance to drought stress in maize, RNA-seq of the public database was used for transcriptome profiling of the seedling stage exposed to drought stress of three levels, such as moderate, severe drought stress and re-watering. In silico analysis of differentially expressed genes (DEGs), 176 up-regulated and 166 down-regulated DEGs was detected at moderated stress in tolerance type. These DEGs was increasing degradation of amino acid metabolism in biological pathways. Six modules based on a total of 4,771 DEGs responses to drought stress by the analysis of co-expression network between tolerance and susceptible type was constructed and showed to similar module types. These modules were discriminated yellow, greenyellow, turquoise, royalblue, brown4 and plum1 with 318, 2433, 375, 183, 1405 and 56 DEGs, respectively. This study was selected 30 DEGs to predicted drought stress response gene and was evaluated expression levels using drought stress treated sample and re-watering sample by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). 23 genes was shown increasing with drought stress and decreasing with re-watering. This study contribute to a better understanding of the molecular mechanisms of maize seedling stage responses to drought stress and could be useful for developing maize cultivar resistant to drought stress.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.2
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• pp.145-149
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• 2017

One of the challenges facing precision manufacturers is the increasing feature complexity of tight tolerance parts. All engineering drawings must account for the size, form, orientation, and location of all features to ensure manufacturability, measurability, and design intent. Geometric controls per ASME Y14.5 are typically applied to specify dimensional tolerances on engineering drawings and define size, form, orientation, and location of features. Many engineering drawings lack the necessary geometric dimensioning and tolerancing to allow for timely and accurate inspection and verification. Plus-minus tolerancing is typically ambiguous and requires extra time by engineering, programming, machining, and inspection functions to debate and agree on a single conclusion. Complex geometry can result in long inspection and verification times and put even the most sophisticated measurement equipment and processes to the test. In addition, design, manufacturing and quality engineers are often frustrated by communication errors over these features. However, an approach called profile tolerancing offers optimal definition of design intent by explicitly defining uniform boundaries around the physical geometry. It is an efficient and effective method for measurement and quality control. There are several advantages for product designers who use position and profile tolerancing instead of linear dimensioning. When design intent is conveyed unambiguously, manufacturers don't have to field multiple question from suppliers as they design and build a process for manufacturing and inspection. Profile tolerancing, when it is applied correctly, provides manufacturing and inspection functions with unambiguously defined tolerancing. Those data are manufacturable and measurable. Customers can see cost and lead time reductions with parts that consistently meet the design intent. Components can function properly-eliminating costly rework, redesign, and missed market opportunities. However a supplier that is poised to embrace profile tolerancing will no doubt run into resistance from those who would prefer the way things have always been done. It is not just internal naysayers, but also suppliers that might fight the change. In addition, the investment for suppliers can be steep in terms of training, equipment, and software.

• Journal of Dairy Science and Biotechnology
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• v.35 no.4
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• pp.249-254
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• 2017

The purpose of this study was to investigate the acid tolerance, bile acid tolerance, and fermentation activity of lactic acid bacteria isolated from Kimchi in the presence of hydrolysates of whey protein concentrate. Kimchi isolates DK109, DK119, DK121, DK128, DK211, DK212, and DK215, which were identified as Lactobacillus sp., and L. casei DK128 showed the highest acid and bile acid tolerance. To produce whey hydrolysates, enzymes were added to a 10% (w/v) whey protein concentrate (WPC) solution at 1:50 (w/v, protein). The viabilities of the DK strains were determined in the presence of low pH and bile salts. Then, yogurt was produced via fermentation with L. casei DK128, an isolate from Kimchi, in the presence of the following additives: CPP, WPC, and WPC hydrolysates (WPCH) generated by alcalase (A) or neutrase (N). The produced yogurts were subjected to various analyses, including viable cell counts (CFU/mL), pH, titratable activity, and sensory testing. After 8 h of fermentation, the pH and titratable activity values of all test samples were 4.2 and 0.9, respectively. The viable counts of LAB were $3.49{\times}10^8$, $5.72{\times}10^8$, $7.01{\times}10^8$, and $6.97{\times}10^8$, for the Control, CPP, A, and N samples, respectively. These results suggest that whey proteins have potential as dietary supplements in functional foods and that WPCH could be used in yogurt as a low-cost alternative to CPP.

• Food Science of Animal Resources
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• v.35 no.4
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• pp.551-556
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• 2015

The aim of this study was to evaluate the functional properties of lactic acid bacteria from various sources and to identify strains for use as probiotics. Ten Lactobacillus strains were selected and their properties such as bile tolerance, acid resistance, cholesterol assimilation activity, and adherence to HT-29 cells were assessed to determine their potential as probiotics. Lactobacillus sp. JNU 8829, L. casei MB3, L. sakei MA9, L. sakei CH8, and L. acidophilus M23 were found to show full tolerance to the 0.3% bile acid. All strains without L. acidophilus M23 were the most acid-tolerant strains. After incubating the strains at pH 2.5 for 2 h, their viability decreased by 3 Log cells. Some strains survived at pH 2.5 in the presence of pepsin and 0.3% bile acid. Lactobacillus sp. JNU 8829, L. acidophilus KU41, L. acidophilus M23, L. fermentum NS2, L. plantarum M13, and L. plantarum NS3 were found to reduce cholesterol levels by ＞50% in vitro. In the adhesion assay, Lactobacillus sp. JNU 8829, L. casei MB3, L. sakei MA9, and L. sakei CH8 showed higher adhesion activities after 2 h of co-incubation with the intestinal cells. The results of this comprehensive analysis shows that this new probiotic strain named, Lactobacillus sp. JNU 8829 could be a promising candidate for dairy products.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.568-575
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• 2018

In order to discover lifespan-extending compounds made from natural resources, activity-guided fractionation of Zingiber officinale Roscoe (Zingiberaceae) ethanol extract was performed using the Caenorhabditis elegans (C. elegans) model system. The compound 6-gingerol was isolated from the most active ethyl acetate soluble fraction, and showed potent longevity-promoting activity. It also elevated the survival rate of worms against stressful environment including thermal, osmotic, and oxidative conditions. Additionally, 6-gingerol elevated the antioxidant enzyme activities of C. elegans, and showed a dose-depend reduction of intracellular reactive oxygen species (ROS) accumulation in worms. Further studies demonstrated that the increased stress tolerance of 6-gingerol-mediated worms could result from the promotion of stress resistance proteins such as heat shock protein (HSP-16.2) and superoxide dismutase (SOD-3). The lipofuscin levels in 6-gingerol treated intestinal worms were decreased in comparison to the control group. No significant 6-gingerol-related changes, including growth, food intake, reproduction, and movement were noted. These results suggest that 6-gingerol exerted longevity-promoting activities independently of these factors and could extend the human lifespan.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.817-821
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• 2012

Soil samples collected from abounded mines of Boryeong area in South Korea were used in isolating bacterial strains and their capacity to solubilize inorganic phosphates and heavy metal tolerance were assessed in vitro. Three different inorganic phosphate sources (Ca phosphate, Fe phosphate, and Al phosphate) and four different heavy metals (Co, Cd, Pb and Zn) each with three concentrations ($100{\mu}g\;mL^{-1}$, $200{\mu}g\;mL^{-1}$, and $400{\mu}g\;mL^{-1}$) were used. The bacterial isolates PSB-1, PSB-2, PSB-3, and PSB-4 solubilized significantly higher amount of Ca phosphate during the first five days of incubation though subsequent drop in soluble phosphorus level in the medium was observed at the later stage (after 5 days) of the incubation. Solubilization of Ca phosphate and Fe phosphate was concomitant with the acidification of the culture medium compared to the control where it remained constant. Isolated strains could solubilize Fe phosphate to certain extent ($25-45{\mu}g\;mL^{-1}$) though solubilization of Al phosphate was found negligible. All the isolates were tolerant to heavy metals (Cd, Pb, and Zn) up to the concentration of $400{\mu}g\;mL^{-1}$ except PSB-1 and PSB-8, which were shown to be vulnerable to Co even at $100{\mu}g\;mL^{-1}$. Heavy metal tolerant strains should be further evaluated for plant growth promoting activities also under field conditions in order to assess their agricultural and environmental significance.