• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.236-245
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• 2000

The feasibility of precision farming for small sized fields was studied by determining fertilizing amount of nitrogenous and calcareous to a cite specific region. A detailed soil survey at three experimental fields of 672㎡, 300㎡ and 140㎡ revealed a considerable spatial variation of the pH and organic matter(OM) levels. Soil organic matter was measured using Walkley-Black method and soil pH was measured with a pH sensor. Soil sample was obtained by Grid Node Sampling Method. The soil sampling depth was 10 - 20 cm from the soil surface. To display soil nutrient variation, a soil map was made using Geographic Information System (GIS) software. In soil mapping, soil data between nodes was interpolated using Inverse Distance Weighting (IDW) method. The variation was about 1 - 1.8 in pH value and 1.4 -7 % in OM content. Fertilizing Amount of nitrogenous and calcareous was determined by the fertilizing equation which was proposed by National Institute of Agricultural Science and Technology.(NIAST). The variation of fertilizing amount was about 3 - 11 kg/10a in nitrogenous and 70 - 140 kg/10a in calcareous. The results showed a feasibility of precision fertilizing for small size fields.

• BMB Reports
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• v.34 no.3
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• pp.250-258
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• 2001

For a long time Rhus verniciflua Stokes (RVS) has traditionally been used as a herbal plant. It is known to contain various biological activities. Previously, a crude ethanol extract from RVS was reported to have antioxidant effects, and antiproliferative activities, on human cancer cell lines. In this report, we prepared a highly purified ethanol extract from RVS, which did not contain the urushiol derivatives, named REEE-1 ($\underline{R}$hus $\underline{e}$thanol $\underline{e}$luted $\underline{e}$xtract-1), to investigate the mechanisms of the scavenging activity of hydroxyl radicals using mouse thymocytes. The results from the deoxyribose, DNA nicking, and glucose/glucose oxidase enzyme assays showed that REEE-1 contained a strong scavenging activity of oxygen free radicals, especially of hydroxyl radicals. However, interestingly, REEE-1 also showed cytotoxicity against the thymocytes, although the effect was variable, depending on the concentrations and times of treatment. The REEE-1-mediated cytotoxicity against thymocytes, which has been used as one of the well-characterized models for apoptosis studies, was verified to be apoptotic. This was proven by the following: the appearance of DNA laddering, increases in DNA fragmentation, low fluorescence intensity in the nuclei after propidium iodide staining, and positive Annexin V staining of the cells. These results suggested that REEE-1 had both antioxidative activity and cytotoxicity against the thymocytes, although the effect of the cytotoxicity was variable, depending on the dose and time of the treatment.

• Korean Journal of Chemical Engineering
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• v.36 no.3
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• pp.356-367
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• 2019

This work presents an advanced and systematic approach to analytically design the optimal parameters of a two parameter second-order internal model control (IMC) filter that satisfies operational constraints on the output process, the manipulated variable as well as rate of change of the manipulated variable, for a first-order plus dead time (FOPDT) process. The IMC parameters are designed to minimize a control objective function composed of the weighted sum of the error between the process variable and the set point, and the rate of change of the manipulated variable, and to satisfy the desired constraints. The feasible region of the constrained IMC control parameters was graphically analyzed, as the process parameters and the constraints varied. The resulting constrained IMC control parameters were also used to find the corresponding industrial proportional-integral controller parameters of a Smith predictor structure.

• Journal of Microbiology and Biotechnology
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• v.20 no.9
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• pp.1322-1330
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• 2010

Three types of nuruk were made from rice, wheat, and a rice-glasswort (6:4) mixture. Nuruk, makgeolli, and vinegar were manufactured with rice nuruk (RN), wheat nuruk (WN), and rice-glasswort nuruk (RGN). The variable region of 18S or 16S rDNA amplified with genomic DNA extracted directly from nuruk-, makgeolli-, and vinegar-making cultures was analyzed via temperature gradient gel electrophoresis (TGGE). The sequence of the 18S rDNA variable region extracted from the TGGE gel for nuruk was 99% homologous with Aspergillus sp. and that for the makgeolli-making culture was 99% homologous with Saccharomyces sp. and Saccharomycodes sp. The sequence of the 16S rDNA variable region extracted from TGGE gel for the vinegar-making culture was 98% homologous, primarily with the Acetobacter sp. The eukaryotic and prokaryotic diversities in the nuruk-, makgeolli-, and vinegar-making cultures was not significantly altered by the addition of glasswort. Prokaryotic diversity was higher than eukaryotic diversity in the nuruk, but eukaryotic diversity was higher than prokaryotic diversity in the makgeolli-making culture, on the basis of the TGGE patterns. No 18S rDNA was amplified from the DNA extracted from the vinegar-making culture. The diversity of the microbial community in the process from nuruk to vinegar was slightly affected by the type of raw material utilized for nuruk-making. The saccharifying activity and ethanol productivity of nuruk, polyphenol content in makgeolli, and acetic acid and polyphenol content in the vinegar were increased as a result of the addition of glasswort. In conclusion, the glasswort may be not simply an activator for the growth of microorganisms during the fermentation of nuruk, makgeolli, or vinegar, but also a nutritional supplement that improves the quality of vinegar.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.522-527
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• 2005

Various processes which produce L-lactic acid using ammonia-tolerant mutant strain, Rhizopus sp. MK-96-1196, in a 3L airlift bioreactor were evaluated. When the fed-batch culture was carried out by keeping the glucose concentration at 30g/L, more than 140 g/L of L-lactic acid was produced with a product yield of 83%. In the case of the batch culture with 200g/L of initial glucose concentration, 121g/L of L-lactic acid was obtained but the low product yield based on the amount of glucose consumed. In the case of a continuous culture, 1.5g/L/h of the volumetric productivity with a product yield of 71% was achieved at dilution rate of $0.024\;h^{-1}$. Basis on these results three processes were evaluated by simple variable cost estimation including carbon source, steam, and waste treatment costs. The total variable costs of the fed-batch and continuous cultures were 88% and 140%, respectively, compared to that of batch culture. The fed-batch culture with high L-lactic acid concentration and high product yield decreased variable costs, and was the best-suited for the industrial production of L-lactic acid.

• BMB Reports
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• v.33 no.3
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• pp.249-255
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• 2000

The Haemophilus influenzae type b (Hib) has been a major cause of bacterial meningitis in children who are less than two years old. The variable (V) region repertoire of adult Caucasian antibodies (Abs) to Hib polysaccharide (PS) has been characterized well. The majority of adult antibodies against Hib uses VL that is derived from the Vk gene A2 and have arginine at the N region. In order to explore the possibility those antibody responses to Hib-PS is variable in various age groups, we examined the VL regions of the antibodies to Hib-PS in Korean adults and children. We immunized Korean adults (n = 8) and children (n = 39) with Hib tetanus conjugated vaccines, isolated RNAs from the peripheral lymphocytes, and amplified the A2-derived VL regions by RT-PCR. The PCR products were subcloned and sequenced. Forty-seven out of 54 independent clones from children used the $J{\kappa}2$, or $J{\kappa}3$ gene in preference. The adults, however, used all of the $J{\kappa}$ genes evenly. With respect to the amino acid sequences of variable regions, adult $A2-J{\kappa}$ recombinants have a germline sequence. But, the 76th codon (AGC) of child $A2-J{\kappa}2$ recombinants was substituted with CGC (arginine) in most cases (88 %) and 77 percent of child clones using the $A2-J{\kappa}3$ genes have isoleucine-109 at the junction of $J{\kappa}-C{\kappa}$ instead of threonine that is found in a germline sequence. These results suggest that the mechanism of antibody production in young children is different from that of adults.

• Advances in nano research
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• v.10 no.1
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• pp.15-24
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• 2021

Microtubules (MTs) are the main part of the cytoskeleton in living eukaryotic cells. In this article, a mechanical model of MT buckling, considering the modified strain gradient theory, is analytically examined. The MT is assumed as a cylindrical beam and a new single variable trigonometric beam theory is developed in conjunction with a modified strain gradient model. The main benefit of the present formulation is shown in its new kinematic where we found only one unknown as the Euler-Bernoulli beam model, which is even less than the Timoshenko beam model. The governing equations are deduced by considering virtual work principle. The effectiveness of the present method is checked by comparing the obtained results with those reported by other higher shear deformation beam theory involving a higher number of unknowns. It is shown that microstructure-dependent response is more important when material length scale parameters are closer to the outer diameter of MTs. Also, it can be confirmed that influences of shear deformation become more considerable for smaller shear modulus and aspect ratios.

• Journal of Biomedical Engineering Research
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• v.10 no.2
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• pp.173-178
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• 1989

A vector quantization technique using a variable block size was applied to image compression of digitized X -ray films. Whether the size of VQ block should be subdivided or not is determined experimentally by the threshold value. The simulation result shows that the performance of the proposed vector quantizer is suitable for the medical image coding, which is applicable to PACS( Picture Archiving and Communication System).

• Molecules and Cells
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• v.45 no.11
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• pp.789-791
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• 2022

Targeting fibroblast growth factor receptors (FGFRs) has been slow compared to other targeted cancer therapies for receptor tyrosine kinases, such as epidermal growth factor receptors. The low efficacy and variable response have limited the growth of FGFR inhibitors in clinical use. Nevertheless, recent systematic and genomic approaches have identified the biological conditions for effectively targeting FGFRs and can accelerate the development of targeted drugs. Under clinical and preclinical trials, the inhibitors started fast growing furious races to target FGFRs. Finally, FGFRs will be more actionable and targetable with more precise and effective drugs at the end of the race, passing the finish line.

• Natural Product Sciences
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• v.24 no.3
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• pp.139-147
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• 2018

The essential oils are fragrant products whose complex compositions are obtained from various parts of plants by dry or steam distillation. Plants with variable biological activities have been explored worldwide. The presence of a large number of phenols, terpenes and other aromatic compounds make essential oils more precise in their mode of action. Because of this, they are known to possess many biological activities like antimicrobial, antioxidant and anti-inflammatory etc. In this article, we will review the published literature summarizing the chemistry of essential oils and their important biological activities.