• Current Photovoltaic Research
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• v.9 no.3
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• pp.75-83
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• 2021

The tunnel oxide passivated contact (TOPCon) structure got more consideration for development of high performance solar cells by the introduction of a tunnel oxide layer between the substrate and poly-Si is best for attaining interface passivation. The quality of passivation of the tunnel oxide layer clearly depends on the bond of SiO in the tunnel oxide layer, which is affected by the subsequent annealing and the tunnel oxide layer was formed in the suboxide region (SiO, Si₂O, Si₂O₃) at the interface with the substrate. In the suboxide region, an oxygen-rich bond is formed as a result of subsequent annealing that also improves the quality of passivation. To control the surface morphology, annealing profile, and acceleration rate, an oxide tunnel junction structure with a passivation characteristic of 700 mV or more (V_oc) on a p-type wafer could achieved. The quality of passivation of samples subjected to RTP annealing at temperatures above 900℃ declined rapidly. To improve the quality of passivation of the tunnel oxide layer, the physical properties and thermal stability of the thin layer must be considered. TOPCon silicon solar cell has a boron diffused front emitter, a tunnel-SiO_x/n⁺-poly-Si/SiN_x:H structure at the rear side, and screen-printed electrodes on both sides. The saturation currents J_o of this structure on polished surface is 1.3 fA/cm² and for textured silicon surfaces is 3.7 fA/cm² before printing the silver contacts. After printing the Ag contacts, the J_o of this structure increases to 50.7 fA/cm² on textured silicon surfaces, which is still manageably less for metal contacts. This structure was applied to TOPCon solar cells, resulting in a median efficiency of 23.91%, and a highest efficiency of 24.58%, independently. The conversion efficiency of interdigitated back-contact solar cells has reached up to 26% by enhancing the optoelectrical properties for both-sides-contacted of the cells.

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.934-953
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• 2021

Ciglitazone is a member of the thiazolidinedione family, and specifically binds to peroxisome proliferator-activated receptor-γ (PPARγ), thereby promoting adipocyte differentiation. We hypothesized that ciglitazone as a PPARγ ligand in the absence of an adipocyte differentiation cocktail would increase adiponectin and adipogenic gene expression in bovine satellite cells (BSC). Muscle-derived BSCs were isolated from six, 18-month-old Yanbian Yellow Cattle. The BSC were cultured for 96 h in differentiation medium containing 5 µM ciglitazone (CL), 10 µM ciglitazone (CM), or 20 µM ciglitazone (CH). Control (CON) BSC were cultured only in a differentiation medium (containing 2% horse serum). The presence of myogenin, desmin, and paired box 7 (Pax7) proteins was confirmed in the BSC by immunofluorescence staining. The CL, CM, and CH treatments produced higher concentrations of triacylglycerol and lipid droplet accumulation in myotubes than those of the CON treatment. Ciglitazone treatments significantly increased the relative expression of PPARγ, CCAAT/enhancer-binding protein alpha (C/EBPα), C/EBPβ, fatty acid synthase, stearoyl-CoA desaturase, and perilipin 2. Ciglitazone treatments increased gene expression of Pax3 and Pax7 and decreased expression of myogenic differentiation-1, myogenin, myogenic regulatory factor-5, and myogenin-4 (p < 0.01). Adiponectin concentration caused by ciglitazone treatments was significantly greater than CON (p < 0.01). RNA sequencing showed that 281 differentially expressed genes (DEGs) were found in the treatments of ciglitazone. DEGs gene ontology (GO) analysis showed that the top 10 GO enrichment significantly changed the biological processes such as protein trimerization, negative regulation of cell proliferation, adipocytes differentiation, and cellular response to external stimulus. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that DEGs were involved in the p53 signaling pathway, PPAR signaling pathway, biosynthesis of amino acids, tumor necrosis factor signaling pathway, non-alcoholic fatty liver disease, PI3K-Akt signaling pathway, and Wnt signaling pathway. These results indicate that ciglitazone acts as PPARγ agonist, effectively increases the adiponectin concentration and adipogenic gene expression, and stimulates the conversion of BSC to adipocyte-like cells in the absence of adipocyte differentiation cocktail.

• Journal of Physiology & Pathology in Korean Medicine
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• v.35 no.2
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• pp.56-63
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• 2021

This study was conducted to find a candidate prescription with anti-inflammatory efficacy of 7 herbal prescriptions known to be effective in atopic dermatitis and sleep disorders in Korean medicine. The anti-inflammatory of the 7 herbal prescriptions extracts were evaluated by ELISA assay and Western blot assay. 7 herbal prescriptions, Seongyutang(SU), Danseontoetang(DST), Sotosajahwan(ST), Jisiljagyagsan(JJ), Seokchangpo(SCP), Wiryeongseon(WLS), Gogojohwan(GGJ) 30 % EtoH extract was used for in vitro experiments. In TNF-α + IFN-γ(TI) stimulated HaCaT cells, all 7 herbal prescriptions reduced TARC and MDC production, and JJ strongly reduced TARC and MDC production at 100 ㎍/ml concentration. SCP strongly reduced MDC production at 10 ㎍/ml and 100 ㎍/ml concentration. In addition, in substance P(SP)/CRH stimulated HMC-1 cells, JJ strongly inhibited VEGF production at both 10 and 100 ㎍/ml concentrations. In LPS/CRH stimulated Raw264.7 cells, all 7 herbal prescriptions significantly inhibited TNF-α. PMA + Ionomycin(PI)/CRH stimulated EL4 cells, SU significantly reduced IL-4 production at both concentrations of 10 and 100 ㎍/ml. WLS significantly reduced IL-17 production at both concentrations of 10 and 100㎍/ml. This suggests that 7 herbal prescriptions have anti-inflammatory effects by reducing inflammatory cytokines in keratinocytes, mast cells and macrophages caused by inflammation. Therefore, it is expected that 7 herbal prescriptions that are effective for sleep disorders and atopic dermatitis can be used as therapeutic materials for sleep disorders and diseases associated with atopic dermatitis.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.394-400
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• 2008

Blast resistance of one hundred and thirty-one rice cultivars bred in Korea was tested with thirty Korean isolates and twenty-two Philippines isolates using three screening methods. In the blast nursery conducted in Korea and in the Philippines, average disease index of rice cultivars were 4.6 and 2.2, respectively. Seventy-nine cultivars showed different resistance reaction in Korea and in the Philippines, and 19 cultivars showed the same resistant reaction in two locations. In the seedling test, Korean blast isolates displayed different levels of virulence. 93-093, a Korean isolate, was compatible with 90 cultivars whereas 97-057 showed a compatible reaction with 13 cultivars. Twenty-three cultivars showed high level of resistance against Korean and Philippines isolates but Chucheongbyeo, Heugnambyeo, and Manmibyeo showed susceptible reaction to all blast isolates. Through the sequential planting test in Korea and in the Philippines, Palgongbyeo and Seomjinbyeo displayed durable resistance, and Nagdongbyeo and Gihobyeo showed high level of disease infection over the planting time. These results indicate that blast isolates collected in two countries have different genetic background and number of compatible isolates should be considered in definition the durability of rice cultivar to rice blast.

• Food Engineering Progress
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• v.13 no.4
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• pp.269-274
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• 2009

The main objective of this study was to establish optimum condition of wet grinding process for manufacturing microparticulated seaweed calcium. Process parameters such as concentration of forming agent, rotor speed, bead size, feed rate, and grinding time were adapted during wet-grinding of seaweed calcium. The particle size range of the raw seaweed calcium was 10-20 $\mu$m. The calcium particles were reduced to under 1 $\mu$m as nano scale after grinding. Gum arabic was suitable for forming agent and 5%(w/v) concentration was the most effective in grinding efficiency. A wet-grinding process operated at 4,000 rpm rotor speed, 0,4 mm bead size, and 0.4 L/hr feeding rate, respectively, produced less than 600 mm(>>90%)-sized particles. In batch systems, 8 cycles of grinding showed higher efficiency, but 20 min of grinding time in continuous processing was more efficient to reduce particle size than the batch processing. Based on the result, the optimum conditions of the wet grinding process were established: operation time of 20 minutes, rotor speed of 4,000 rpm, bead size of 0.4 mm, feed rate of 40 mL/min and 30% mixing ration with water. The size of the resulting ultra fine calcium particles ranged between 40 and 660 mm.

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.33-38
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• 2019

Ochratoxin A (OTA), one of mycotoxins produced mainly by Aspergillus is a common contaminant of stored grains, posing health hazards to human and livestock. The aim of this study is to explore ability of isolated bacteria Bacillus subtilis AF13 and Streptomyces shenzhenensis YR226 to remove OTA. AF13 and YR226 could remove 94.23 and 97.73% of OTA ($100{\mu}g/L$), respectively during 24 h incubation in NB medium. When cultures of two strains were separated into washed cells and cell-free supernatant, the supernatant of both strains removed more than 90% of $100{\mu}g/L$ OTA, and 98.88% of OTA could be also removed by the washed cells of YR226. OTA removal occurred in a few second by the supernatant of both strains, and treatments of autoclaving, proteinase K and chymotrypsin did not affect the OTA removal by the culture supernatants, which indicate that some thermostable and non-proteinaceous substances secreted by these bacteria may be involved in OTA removal in these two bacteria. These results suggest that AF13 and YR226 can be used to remove OTA from OTA-contaminated grains and feeds, and therefore decrease economic damage in agriculture and feed industry.

• Journal of Soil and Groundwater Environment
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• v.23 no.6
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• pp.90-103
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• 2018

Although fluoride is an essential trace element, ingestion of excessive amount of fluoride could have detrimental effect on human health. Generally, the bioavailability of fluoride in soils was low, but it could be harmful to the environment depending on the soil properties. Therefore, it is necessary to understand the concentration distribution, and fate and transport characteristics of fluoride to establish a resonable management strategy for fluoride pollution. This study was conducted to evaluate nationwide fluoride distribution in soils in Korea, as well as its fate and transport characteristics. The average background concentration was 204.5 (15.3~504.8) mg/kg, which is lower than the values of foreign soils. For the three regions of different land use, the average concentration was 229.6 mg/kg in region 1, 195.7 mg/kg in region 2, and 273.4 mg/kg in region 3. The concentration of fluoride was the highest in soils from Youngnam block within tectonic structure derived from metamorphic rocks. The results of sequential extraction to access F bioavailability showed fluoride in soils mainly existed as a residual form, which suggests the bioavailability of fluoride was relatively low. Soil properties such as soil pH, CEC, and clay content were found to affect F bioavailability of soil.

• Communications of Mathematical Education
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• v.32 no.4
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• pp.495-517
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• 2018

This paper is based on the effects of Zone of Proximal Development and scaffolding theory of social constructivist, Russian psychologist Vygotsky. He insisted that a social interaction play a fundamental role in the development of cognition. This study is to examine the efficient of the scaffolding types in Math class. The ZPD is the distance between a student's ability to perform a task under adult guidances or with peer collaboration and the student's ability solving the problem independently. To conduct the research was grouped into an experimental first grader five students in H high school in Y county. After class, students were questioned through Semi-structured interviews. The results of this study are below. First, Students were satisfied with the class mixed micro-scaffolding types and Macro-scaffolding types and improved their math thinking ability and the ways of solving problems. Second, The results of the class showed that students' ability to perform a task was transferred to the higher level through the help of a teacher or peers. Students could have more time to listen to peers' opinions and to say their own thoughts freely than they were under the lecture method instruction. Third, Students were interested in math through the experimental class. That's because the appropriate help of the scaffolding type, a cooperate study, relative with real life, using an engineering tools. They made a change of perception.

• The Korean Journal of Food And Nutrition
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• v.32 no.2
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• pp.114-121
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• 2019

This study evaluates the quality properties of soy-paste soybean cultivar for fermented soybean products. The six soybean varieties that include Jinpung, Saedanbaek, Daepung 2, Pyeongwon, Cheonga and Saeolkong were used in the experiment. The range of water uptake ratio, hardness after soaking and hardness after steaming were 117.00~131.33%, 1.65~3.30 kg and 0.05~0.14 kg, respectively. The physicochemical analysis indicated the following: Moisture content, 63.27~68.72%; pH, 6.43~6.60; total acidity, 0.27~0.45%. Color values for L value (lightness), a value (redness), and b value (yellowness) ranged from 39.07~67.92, 7.64~11.79, and 7.48~20.67, respectively. The amylase and protease activities of the Saedanbaek samples were the highest among all cultivars. The amount of viscous substance in the fermented soybean products by cultivars ranged from 5.93 to 8.37%, and Saedanbaek was the highest. The total viable cells counts for soybean fermented products were 9.11~9.42 log CFU/g. The amino-type nitrogen contents of all samples were in the range of 401.07 to 524.47 mg% and Saedanbaek cultivars showed the highest content (524.47 mg%). Based on the results, Saedanbaek will be suitable as a soy-paste soybean cultivar and the quality standards for the fermentation process of the fermented soybean products.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.12
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• pp.1963-1973
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• 2018

Objective: This study was conducted to evaluate the effect of dietary energy and lipase supplementation on growth performance, nutrient digestibility, serum profiles, intestinal morphology, small intestinal digestive enzyme activities, biochemical index of intestinal development and noxious gas emission in weaning pigs. Methods: A total of 240 weaning pigs ([Yorkshire${\times}$Landrace]${\times}$Duroc) with an average body weight (BW) of $7.3{\pm}0.12kg$ were used in this 28-d experiment. Weaning pigs were randomly allocated to 4 dietary treatments in a $2{\times}2$ factorial arrangement with 2 levels of energy (net energy = 2,470 kcal/kg for low energy diet and 2,545 kcal/kg for basal diet) and 2 levels of lipase (0 and 1.5 U/g of lipase) according to BW and sex. There were 6 replications (pens) per treatment and 10 pigs per pen (5 barrows and 5 gilts). Results: Weaning pigs fed the low energy diet had lower (p<0.05) gain-to-feed ratio (G:F) throughout the experiment, apparent digestibility of dry matter, nitrogen, ether extract, and gross energy during d 0 to 14, average daily gain during d 15 to 28, lipase activity in duodenum and ileum and protein/DNA in jejunum (p<0.05), respectively. Lipase supplementation had no effect on growth performance but affected apparent nutrient digestibility (p<0.05) on d 14 and enhanced lipase activity in the duodenum and ileum and protease activity in duodenum and jejunum of pigs (p<0.05) fed the low energy diet. Lipase reduced serum low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG), $NH_3$ production (p<0.05) from the feces. Conclusion: The low energy diet decreased G:F throughout the experiment and nutrient digestibility during d 0 to 14 as well as lipase activity in duodenum and ileum. Lipase supplementation increased nutrient digestibility during d 0 to 14 and exerted beneficial effects on lipase activity in duodenum and ileum as well as protease activity in duodenum and jejunum, while reduced serum LDL-C, TG and fecal $NH_3$.