• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1124-1129
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• 2011

The importance of environment-friendly agriculture is being magnified as a new growth engine industry in pursuit of low carbon, green growth policies. In order to provide technical supports for pushing ahead with the environment-friendly agriculture policies, we estimated the effects of customized fertilization on growth and yield of rice and fertilizer reduction compared to conventional fertilization and single-element fertilization. In rice plant growth and rice yield, no statistically significant difference between the three fertilization treatments was observed. In contrast, customized fertilization showed high disaster resistance reducing the damage caused by rice lodging during a typhoon. The average N application in farms showing high rice lodging amounted to $135kg\;N\;ha^{-1}$ while $135-138kg\;N\;ha^{-1}$ was known as the critical range of rice lodging in Korea. The fertilizer reduction rate of customized fertilization compared to conventional fertilization of investigated farms was on average 22.5%. We estimated the short-term effects of customized fertilization in the first year after application. In future, there is need for continuous examination of rice growth and soil environment change due to successive application of customized fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.962-967
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• 2010

The influences of the different mixture of urea fertilizer and pig manure compost as a nitrogen (N) source on Chinese cabbage yield, N uptake, and N agronomic efficiency (AE) were evaluated in two soils having different soil fertility levels. Increasing urea application level was very effective to improve yield and N uptake of Chinese cabbage, and the highest yield was obtained by urea fertilization alone in two soils. On the other hand, the lowest yield and N uptake was obtained from compost alone application in two soils. There was no significant difference in terms of the nitrogen AE between low and high fertility soils that were fully applied with urea. The AE values of Chinese cabbage applied by compost alone were significantly higher in the soil having a low fertility (28.8 g $g^{-1}$) than that in soil with high fertility (16.2 g $g^{-1}$), suggesting that N in compost was more responsive in improving the yield of Chinese cabbage in low fertility soils.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.937-944
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• 2010

Cu and Zn can be accumulated in plastic film house soils by long-term application of livestock manure or compost. The mobility and bioavailability of Cu and Zn accumulated in soils are strongly influenced by their chemical or geochemical species in soils. In order to assess the accumulation, mobility, and bioavailability of Cu and Zn in plastic film house soils, we determined their geochemical species using a sequential extraction, grouped into three pods: the total pool, the potentially mobil pool, and the mobil pool. Total contents of Cu and Zn, ranged from 14.9 to 53.1 mg $kg^{-1}$ for Cu and from 55.4 to 169 mg $kg^{-1}$ for Zn, lied by far below the soil contamination standards, but exhibited little accumulation compared with their geogenic concentrations. Mobile contents of Cu and Zn and their percentage of total contents were strongly affected by soil pH in addition to total contents and soil organic matter. Mobile contents of Cu, ranged from <0.01 to 1.71 mg $kg^{-1}$, showed their minimum between pH 5.0 and 6.0 and increased above pH 6.0 to 8.0. In contrast, mobile contents of Zn, varied from <0.01 to 12.4 mg $kg^{-1}$, showed their minimum above pH 7.0 and increased strongly with decreasing pH below 5.5~6.0. Potentially mobile and total contents of Cu and Zn rose with ascending soil organic matter. To assess ecological and toxic effects of Cu and Zn in soils, mobile and potentially mobile contents, as bioavailable and potentially bioavailable pools, should be considered more important than total contents.

• Journal of Plant Biotechnology
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• v.48 no.3
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• pp.124-130
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• 2021

Nitrate is an important nutrient and signaling molecule in plants that modulates the expression of many genes and regulates plant growth. In this study, we cover the research status of transcription factors related to the control of gene expression by nitrate signaling in higher plants. Nitrate reductase is a key enzyme in nitrogen assimilation, as it catalyzes the nitrate-to-nitrite reduction process in plants. A variety of factors, including nitrate, light, metabolites, phytohormones, low temperature, and drought, modulate the expression levels of nitrate reductase genes and nitrate reductase activity, which is consistent with the physiological role if. Recently, several transcription factors controlling the expression of nitrate reductase genes have been identified in higher plants. NODULE-INCEPTION-Like Proteins (NLPs) are transcription factors responsible for the nitrate-inducible expression of nitrate reductase genes. Since NLPs also control the nitrate-inducible expression of genes encoding the nitrate transporter, nitrite transporter, and nitrite reductase, the expression levels of nitrate reduction pathway-associated genes are coordinately modulated by NLPs in response to nitrate. Understanding the function of nitrate in plants will be useful to create crops with low nitrogen use.

• Journal of the Korean Society of Food Culture
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• v.36 no.4
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• pp.362-372
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• 2021

The present study was undertaken to investigate the quality characteristics of Korean Woori black pig (KWP) bellies and loins by different slaughter weight (SW) groups. The loin and belly samples collected from KWPs with different body weights (50, 75, 90, 105, and 120 kg) at 24 h post-mortem were used in the present investigation. The samples were analyzed for quality traits, fatty acid profiles, and volatile flavor compounds. Results showed that the fat content of the loin (8.64%) and belly samples (46.78%) was significantly higher in the 120 kg SW group compared to those of other SW groups (p<0.05). However, a lower protein content (12.20-12.67%) was found in the belly cuts of the heavier SW groups (105-120 kg) compared to those of the lighter SW groups (p<0.05). The lowest cooking loss (24.34%) was found in the loin cuts of the 120 kg SW group (p<0.05). Both the loin and belly cuts were observed to be redder in color with increasing SW (p<0.05). Higher oleic acid (C18:1, n9) and total monounsaturated fatty acid content and lower linolenic acid(C18:3, n3) and total polyunsaturated fatty acid content were observed in both cuts of the 120 kg SW group (p<0.05). Out of the flavor compounds identified, 11 and 17 compounds in the loin and belly, respectively, were associated with the SW. An increase in the SW resulted in increased concentrations of C18:1n9- and amino acid-derived flavor compounds. Overall, the meat samples of the heavier SW groups (120 kg) exhibited better quality and higher concentrations of volatile compounds associated with pleasant flavors. However, the meat of the 120 kg SW group also contained a much higher fat level (8.64 and 46.78% in the loin and belly, respectively) that may result in high trimming loss and hence a high rejection risk by consumers.

• Journal of Conservation Science
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• v.37 no.5
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• pp.464-476
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• 2021

Various materials, depending on the personality of the artist, are required for contemporary art. Thus, it is necessary to decipher the expressive intentions of the artist and characteristics of the materials required for the conservation of such art. The purpose of this study is to analyze the causes underlying the deterioration of sculptures made from soap and to determine the ideal hygrothermal environment required to stably exhibit and store these artworks. Furthermore, we aim to maintain the long-term structures of the artworks in accordance with the changing expressions and intentions of the artist. Our analysis confirmed that the extracts of the soap sculptures were composed of glycerin and that the sculptures were sensitive to humidity. Moreover, we determined that a relative humidity (RH.) of approximately 60~65% made for an appropriate hygrothermal environment required to preserve the sculptures. We also preserved each work in various ways by applying appropriate preservation treatment, and found that the optimum preservation environment for soap sculptures was a temperature of 20±2℃ and a RH. of 60±5%.

• Journal of Conservation Science
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• v.37 no.5
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• pp.516-524
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• 2021

The 'artist's intention' plays an important role in the conservation process of contemporary art. Accordingly, the information on artworks owned by the artist, their bereaved family members, and foundations that have decision-making power is important. The artist's interview is the kind of data that can clear 'artist's intentions' to ensure reliable conservation treatment can be carried out even after the artist's death. Therefore, this study attempted to use information from the artist's interview on the type of wood in the manufacture of the filler required for lifted and separated bark conditions in the conservation process of wooden artwork in the National Museum of Modern and Contemporary Art. While the conservation treatment resulted in the stable preservation of the bark of artwork, an analysis of the wood confirmed that the information in the artist's interview was not true. Consequently, we suggest that attention must be paid toward the information provided by artist, their bereaved families, etc. Based on the result of this study, this is also expected to help preserve upcoming artworks with similar bark conditions.

• Composites Research
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• v.34 no.5
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• pp.290-295
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• 2021

The application of lightweight structural composites to automobiles as a solution in line with global fuel economy regulations to curb global warming is recognized as a megatrend. This study was conducted to provide a technical approach that can respond to the issue of replacing parts that require conductive properties to maximize the application of thermoplastic carbon fiber reinforced plastics (CFRPs), which are advantageous in terms of repair, disposal and recycling. By utilizing the properties of the low-viscosity polymerizable oligomer matrix, it was possible to prepare a thermoplastic CFRP exhibiting excellent impregnation properties while uniformly mixing the conductive filler. Various carbon-based conductive fillers such as carbon black, carbon nanotubes, graphene nanoplatelets, graphite, and pitch-based carbon fibers were filled up to the maximum content, and electrical and thermal conductive properties of the fabricated composites were compared and studied. It was confirmed that the maximum incorporation of filler was the most important factor to control the conductive properties of the composites rather than the type or shape of the conductive carbon filler. Experimental results were observed in which it might be advantageous to apply a one-dimensional conductive carbon filler to improve electrical conductivity, whereas it might be advantageous to apply a two-dimensional conductive carbon filler to improve thermal conductivity. The results of this study can provide potential insight into the optimization of structural design for controlling the conductive properties of thermoplastic CFRPs.

• Korean Journal of Optics and Photonics
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• v.32 no.4
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• pp.147-152
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• 2021

We report high-power continuous-wave operation of a Yb-doped fiber laser at 1070 nm, pumped by high-power laser diodes at 976 nm. Based on theoretical calculation of the stimulated Raman scattering and temperature distribution in the fiber, we construct a bidirectionally pumped Yb-fiberlaser system incorporating a pair of fiber Bragg gratings and a cladding light stripper. The fiber laser yields 3.0 kW of continuous-wave output at 1070 nm in a diffraction-limited beam with M² ≈ 1.26 for 4.1 kW of incident pump power, corresponding to a slope efficiency of 81.5%. The prospects for further power scaling are discussed.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.2
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• pp.238-247
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• 2021

Congenital tooth agenesis is the most common developmental dental anomaly, of which oligodontia is defined as the absence of six or more permanent teeth, except the third molars. Tooth agenesis causes malocclusion, alveolar atrophy, aesthetic and psychosocial problems. This clinical report describes a multidisciplinary treatment for a patient diagnosed as oligodontia, who exhibited absence of 14 permanent teeth, atrophy of maxillary alveolar bone, and mandibular protrusion. Restoration space was secured and tooth axis was improved by the extraction of deciduous teeth and orthodontic treatment. However, edge-to-edge bite of posterior teeth and arch dimension discrepancy due to atrophic maxilla was remained. To restore the aesthetics and functionality, implant retained prosthesis was planned. Considering minimal bone grafts, location and number of dental implants and prostheses design were determined. Through the gradual adjustment of provisional restoration, the appropriate centric and eccentric occlusion was reflected into a definitive prosthesis. Currently, stable functional results were attained, however, regular follow up and maintenance care over lifetimes should be performed.