• The Korean Journal of Ecology
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• v.27 no.3
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• pp.147-153
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• 2004

The objective of this study was to understand differences among three half-sib families of Betula schmidtii seedlings in the effect of three Cd levels on growth and photosynthesis. One-year-old seedlings of B. schmidtii were treated with 0, 0.4 and 0.8 mM CdSO$_4$ㆍ8/3$H_2O$ for two months. Growth and physiological responses to Cd treatment levels of three families determined using dry weight, relative height growth rate(RHGR), apparent quantum yield and carboxylation efficiency. The B. schmidtii seedlings exposed to 0.4 and 0.8 mM Cd showed statisticall significant decrease in dry weight and RHGR relative to controls. In addition, the growth inhibition of B. schmidtii seedlings was accompanied by a significant decrease in net photosynthesis measured as $CO_2$ assimilation. Apparent quantum yield and carboxylation efficiency were also affected by Cd treatment, undergoing a significant and progressive reduction with increasing Cd concentrations in all families. We also found significant difference among three families of B. schmidtii in growth, biomass and photosynthesis when exposed to Cd stress. Therefore the present study showed that the difference in Cd tolerance among families might be attributed to genetic factor in response to Cd stress.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.5
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• pp.392-397
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• 2012

In the $(La_{0.8}Ca_{0.2})(Cr_{0.9}Co_{0.1})O_3$ (LCCC), which has been using as interconnector materials in SOFC, Al ions were substituted for Co because ionic radius of Al is similar to that of Co. Because of the almost identical ionic radius of Al and Co, the substitution was not thought to be affect the tolerance factor of LCCC, and the densification behavior, high temperature electrical conductivity and thermal expansion coefficient were examined as a function of Al concentration. In the cases of the x= 0 and x= 0.02 in $(La_{0.8}Ca_{0.2})(Cr_{0.9}Co_{0.1-x}Al_x)O_3$ (x= 0~0.1), the samples showed the relative densities above ${\geq}95%$ when those were sintered at ${\geq}1,350^{\circ}C$. In the case of the $x{\geq}0.06$ the sintered density deteriorated greatly at lower sintering temperatures. High temperature electrical conductivity of the samples decreased as the content of Al increased. Since the valence state of Al ion is unchangeable, while Cr or Co ions contribute to the electrical conduction by changing those valence states, Al substitution resulted in the decreased electrical conductivity. Al doping of LCCC was an effective way of decreasing the thermal expansion coefficient (TEC).

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.124-131
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• 2010

This study was conducted to investigate the potentials for the forest restoration on reclaimed land by using willow trees (Salix koreensis Anderson) selected from a coastal reclaimed land made in inside of the Sihwa tide embankment. We first collected six individual willow trees that were the only tree species grown in the reclaimed land. Total 7 clones from cuttings of the collected trees and the control were grown in a greenhouse for two months prior to applying the different concentrations of NaCl solutions (0.0%, 0.1%, 0.5%, and 1.0%). One month after the NaCl application, the survival rates of clones from both the collected trees, and the control were significantly decreased in a NaCl dose-dependent manner. However, there was no significant difference between the collected trees and the control in terms of survival rate, hight and diameter of cuttings, and the numbers of leaves in greenhouse condition. In conclusion, the willow trees collected from the coastal reclaimed land showed no tolerance against NaCl compared to the control grown in ordinary soil, suggesting that further study is required to determine what the most important factor is to select salt tolerant tree species.

• The Korean Journal of Applied Statistics
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• v.29 no.3
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• pp.409-424
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• 2016

This study analyzed the causal relationship among factors that influence the purchase intensions for individual pensions which have a growing importance as a financial means after retirement. For this purpose, structural equation modeling based on the survey data (N = 928) was conducted to analyze psychological factors and financial factors comprehensively. According to empirical results of the structural equation, in the case of non-subscribers of individual pensions, potential longevity and coping efficacy influenced the purchase intensions for individual pensions fully mediated by fear and worry about longevity. Trust in insurers and risk tolerance directly influenced the purchase intensions for individual pensions. These show that trust in insurers is the most important factor in purchase intensions for individual pensions. Also, only trust in insurers give a direct impact on individual pensions in the case of individual pension subscribers. Longevity-related emotional side is expected to help in marketing activities that target potential customers signing individual pensions. In addition, trust in insurers has the greatest impact on new and additional subscriptions that represent critical efforts to improve trust in insurers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1576-1584
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• 2013

This study is carried out to assess the relative effects of different doses of dietary glucose or fructose on non-alcoholic fatty liver disease (NAFLD) and hepatic metaflammation in a rodent model of type 2 diabetes. KK/HlJ male mice were fed experimental diets as follows: 1) control (CON), 2) moderate glucose (MG, 30% of total calories as glucose), 3) high glucose (HG, 60% of total calories as glucose), 4) moderate fructose (MF, 30% of total calories as fructose), and 5) high fructose (HF, 60% of total calories as fructose) for three weeks. Food intake was not affected by treatments. Compared with HF, HG not only increased serum fasting glucose and area under the curve during oral glucose tolerance test, but also decreased the levels of serum insulin and adiponectin. It indicated that glucose control was complicated via high glucose intake. High fructose treatment led to increased triglyceride in the serum and liver. In comparison to HG, high fructose diet activated NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome consisting of apoptosis-associated speck-like protein containing a CARD (ASC), NLRP3 and caspase 1, which increases interleukin (IL)-$1{\beta}$ maturation and secretion. The activation of NLRP3 inflammasome was accompanied by increased levels of tumor necrosis factor alpha (TNF-${\alpha}$) and IL-6. However, the expression of NLRP3 inflammasome components and pro-inflammatory cytokines did not differ between CON and HG. These data suggested that dietary fructose triggers hepatic metaflammation accompanied by NLRP3 inflammasome activation and has deleterious effects on NAFLD.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.2
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• pp.267-272
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• 2017

Piceatannol (PIC) is a natural hydroxylated analog of resveratrol (RSV), which is a polyphenol known to extend lifespan by stimulating sirtuins. The aim of this study was to investigate the effects of PIC and RSV on the toll-like receptor 4 (TLR4)-nuclear factor kappa B ($NF-{\kappa}B$) pathway in mouse hepatocytes and an obese/diabetic KK/HlJ mouse model. AML12 mouse hepatocytes in the absence or presence of palmitic acids (PA) were treated with PIC ($50{\mu}M$) or RSV ($50{\mu}M$). Male KK/HlJ mice at 20 weeks of age were divided into three subgroups as follows: 1) obese and diabetic control (KK), 2) KK_PIC, and 3) KK_RSV. PIC and RSV were administered orally at a dose of 10 mg/kg/d for 4 weeks. Four weeks of PIC and RSV treatment did not affect body weight or food intake in KK mice. Serum fasting blood glucose was significantly reduced in KK_PIC, and 2 h oral glucose tolerance test area under the curve was significantly reduced by PIC and RSV treatment in KK mice. PIC tended to improve homeostasis model assessment of the insulin resistance index (HOMA-IR) and HOMA beta-cells in diabetic KK mice. TLR4 and $NF-{\kappa}B$ were down-regulated by PIC and RSV treatments in hepatocytes in the absence or presence of PA. Insulin receptor, AMP-activated protein kinase, peroxisome proliferator-activated receptor gamma, nucleotide oligomerization domain-like receptor family pyrin domain-containing 3, interleukin-1, and $NF-{\kappa}B$ were altered in PIC-treated livers. Collectively, PIC and RSV inhibited the $TLR4-NF-{\kappa}B$ pathway, and PIC seems to be more effective than RSV in the regulation of analyzed targets, which are involved in insulin signaling and inflammation in vivo.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.127-127
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• 2017

Aluminum is the most abundant metallic element in the Earth's crust and considered as the most limiting factor for plant productivity in acidic soils. The inhibition of root growth is recognized as the primary effect of Al toxicity. Seeds of wheat cv. Keumkang (Korean cultivar) were germinated on petridish for 5 days and then transferred hydroponic apparatus which was treated with $0{\mu}M$ $AlCl_3$ (control), $100{\mu}M$ $AlCl_3$ and $150{\mu}M$ $AlCl_3$ for 5 days. The length of roots, shoots and fresh weight of wheat seedlings were decreased under aluminum stress. The concentrations of $K^+$, $Mg^{2+}$ and $Ac^{2+}$ were decreased whereas $Al^{3+}$ and $P_2O_5{^-}$ concentration was increased under aluminum stress. Using confocal microscopy, the fluorescence intensity of aluminum was increased with morin staining. In this study, a proteome analysis was performed to identify proteins, which is responsible to aluminum stress in wheat roots. In 10-day-old seedlings, proteins were extracted from roots and separated by 2-DE, stained by CBB. Using image analysis, a total of 47 differentially expressed protein spots were selected, whereas 19 protein spots were significantly up-regulated such as s-adenosylmethionine, oxalate oxidase, malate dehydrogenase, cysteine synthase, ascorbate peroxidase and 28 protein spots were significantly down-regulated such as heat shock protein 70, o-methytransferase 4, enolase, amylogenin by aluminum stress following protein spots analyzed by LTQ-FTICR mass spectrometry. The results provide the global picture of Al toxicity-induced alterations of protein profiles in wheat roots, and identify the Al toxicity-responsive proteins related to various biological processes that may provide some novel clues about plant Al tolerance.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.140-140
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• 2017

Nutritious and functional foods from crop have received great attention in recent years. Colored-grain wheat contains high phenolic compound and a large number of flavonoid. The anthocyanin and polyphenolic synthesis and accumulation is generally stimulated in response to biotic or abiotic stresses. Here, we analyzed genome wide transcripts in seedling of colored-grain wheat response to ABA and PEG treatment. About 900 and 1500 transcripts (p-value < 0.05) from ABA and PEG treatment were aligned to IWGSC1+popseq DB which is composed of over 110,000 transcripts including 100,934 coding genes. NR protein sequences of Poaceae from NCBI and protein sequence of transcription factors originated from 83 species in plant transcription factor database v3.0 were used for annotation of putative transcripts. Gene ontology analysis were conducted and KEGG mapping was performed to show expression pattern of biosynthesis genes related in flavonoid, isoflavonoid, flavons and anthocyanin biopathway. DroughtDB (http://pgsb.helmholtz-muenchen.de/droughtdb/) was used for detection of DEGs to explain that physiological and molecular drought avoidance by drought tolerance mechanisms. Drought response pathway, such as ABA signaling, water and ion channels, detoxification signaling, enzymes of osmolyte biosynthesis, phospholipid metabolism, signal transduction, and transcription factors related DEGs were selected to explain response mechanism under water deficit condition. Anthocyanin, phenol compound, and DPPH radical scavenging activity were measured and antioxidant activity enzyme assays were conducted to show biochemical adaptation under water deficit condition. Several MYB and bHLH transcription factors were up-regulated in both ABA and PEG treated condition, which means highly expressed MYB and bHLH transcription factors enhanced the expression of genes related in the biosynthesis pathways of flavonoids, such as anthocyanin and dihydroflavonols in colored wheat seedlings. Subsequently, the accumulation of total anthocyanin and phenol contents were observed in colored wheat seedlings, and antioxidant capacity was promoted by upregulation of genes involved in maintaining redox state and activation of antioxidant scavengers, such as CAT, APX, POD, and SOD in colored wheat seedlings under water deficit condition. This work may provide valuable and basic information for further investigation of the molecular responses of colored-grain wheat to water deficit stress and for further gene-based studies.

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.264-271
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• 2016

The objective of this study was to determine the growth and light utilization efficiency of garden plants in shade area through chlorophyll fluorescence reaction analysis. Ten garden plants was grown for 75 days under 50% and 80% shading conditions. Under shading, $ET2_O/RC$, the fluorescence parameter related to electron-transport in photosystem II, was effectively enhanced. However, the electron transport flux until PSI acceptors per reaction center ($RE1_O/RC$) was reduced. These changes in photochemical parameters evoked a decrease in performance index (PI) and driving force (DF) of electron transport flux. In addition, some photochemical parameters such as $F_V$, $FV/F_O$, $RE1_O/RC$, $ET2_O/RC$, $PI_{TOTAL\;ABS}$, and $DF_{TOTAL\;ABS}$ were found to be important for shade tolerance. Three species (Pachysandra terminalis Siebold & Zucc, Physostegia virginiana L., and Carex maculata Bott) were found to be shade tolerant. Based on these results, shading factor index (SFI) deduced from photochemical parameters is useful for evaluating of shading stress of garden plants.

• Korean Journal of Ichthyology
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• v.19 no.2
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• pp.154-159
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• 2007

The oblong rockfish, Sebastes oblongus has recently drawn attention from aquaculturists because of its marketable value and tolerance against winter water temperature in the southern coastal waters of the Korean peninsula. In the study of temperature effect on growth, water temperature $16^{\circ}C$ showed best growth. The upper temperature of the fish showed feeding activity was $27^{\circ}C$ over which the fish showed no longer feeding activity. Stocking density was also a critical factor affecting the growth and survival of the juvenile fish. The best growth was in the density of 200 juveniles/L, while the highest survival was in the density of 100 juveniles/L. A feeding experiment was conducted to determine the effects of feeding frequency on growth and survival. A feeding scheme of twice a day was good enough in the sense of growth, survival, and economy. These results indicate that parameters such as water temperature, density, tank size and feeding frequency are consideration for best seed production of the fish.