• Journal of Korean Society on Water Environment
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• v.33 no.5
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• pp.546-555
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• 2017

The Nutrient budget is one of the agricultural-environment indicators of OECD. A nutrient budget measures the surplus as the differential between the inputs and the outputs of within a certain boundary and within a specified period of time (i.e. one year). According to OECD, the annual nitrogen budget for Korea was $245kg\;N\;ha^{-1}$ in 2014, which corresponds to the first position among OECD countries. In Korea in 2014, about 90 % of livestock excreta was composted as solid and liquid manure, which are usually and customarily spread on agricultural land. The objectives of this study are intended to suggest methodology of the regional nitrogen budget as a nitrogen management tool, which considers conversion from raw excreta to composted manures based on the methodology of OECD/Eurostat, and application of the new method in an agricultural region of Korea. As a result, the calculated excess rate of hydrospheric nitrogen surplus was $251kg\;N\;ha^{-1}$ (in the region in 2014), which indicates the presence of potential risks emanating from excessive nitrogen, with regard to both export water and soil environments. The findings also assert that this was shown to be one of the most important elements in the nitrogen budget, which translates to the actual amounts of nitrogen lost during the solid composting process. To better understand the process and the reliability of the method, it is necessary to analyze the sensitivity of the relevant co-efficients used in the method in the near future.

• Membrane Journal
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• v.17 no.4
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• pp.345-351
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• 2007

In this research, by using the fluorine gas, the poly(ether sulfone) (PES), the polysulfone (PSf), and the poly-vinylidenefluoride (PVDF) membranes were modified to improve the performance of the optional Gas-Liquid Contactor The SEM, surface contact angle, XPS, and the water transmission minimum pressure test was performed in order to examine the characteristics of which is surface modified. As a result of looking into the surface morphology of from the SEM measurement, we could know that the roughness of the membrane surface increased as the fluorine processing time increased. $-CH_2$, and the perfluoro group of $-CH_3$ were chemically combined with the surface fluorine conversion film surface and the hydrophobicity was exposed to be increased. Moreover, we could know that as the surface fluorinated processing time increased from the surface contact angle and water transmission minimum pressure test, the measured value increased and the overall characteristics were improved.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2001.12a
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• pp.22-37
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• 2001

Melatonin is secreted during the hours of darkness and is thought to influence the circadian and seasonal timing of a variety of physiological processes. Serotonin N-acetyltransferase (AA-NAT) which is found to be expressed in pineal gland, retina, and various tissues, catalyses the conversion of serotonin to N-acetylserotonin and is known as the rate-limiting enzyme in the biosynthetic pathway of melatonin. The compounds that modulate the activity of AA-NAT can be used to treat serotonin-and melatonin-related diseases such as insomnia, depression and seasonal affective disorders (SAD). Several assay methods have been developed by which to measure AA-NAT activity. We have also developed a simple, rapid and sensitive AA-NAT assay method that takes advantage of differences in the organic solubilities between acetyl CoA and N-acetyltryptamine. We screened modulators of AA-NAT activity from the water extracts of the medicinal plants. We found MNP1005 which strongly inhibited the activity of AA-NAT ($IC_{50}$=2.2$\mu$M). Enzyme inhibitory kinetic studies revealed that MNP1005 exhibited a noncompetitive inhibition toward tryptamine. The antidepressant effect of MNP1005 was investigated on behavioral despair test so called forced swimming test (FST). MNP1005 significantly increased swimming behavior by reducing immobility with treatment of 10 mg/kg when compared to the vehicle-treated control group (P < 0.05). This suggests that MNP1005 possesses antidepressant activity. The influence of chronic MNP1005 treatment on the expression of brain-derived neurotrophic factor (BDNF) was examined by in situ hybridization and Northern blot. Chronic treatment of MNP1005 blocked the downregulation of BDNF mRNA in the frontal cortex and other cortex regions in response to restraint stress.

• Journal of Ginseng Research
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• v.39 no.2
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• pp.183-187
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• 2015

Background: Gut microflora play a crucial role in the biotransformation of ginsenosides to compound K (CK), which may affect the pharmacological effects of ginseng. Prebiotics, such as NUTRIOSE, could enhance the formation and consequent absorption of CK through the modulation of gut microbial metabolic activities. In this study, the effect of a prebiotic fiber (NUTRIOSE) on the pharmacokinetics of ginsenoside CK, a bioactive metabolite of ginsenosides, and its mechanism of action were investigated. Methods: Male Sprague-Dawley rats were given control or NUTRIOSE-containing diets (control diet + NUTRIOSE) for 2 wk, and ginseng extract or vehicle was then orally administered. Blood samples were collected to investigate the pharmacokinetics of CK using liquid chromatography-tandem mass spectrometry. Fecal activities that metabolize ginsenoside Rb1 to CK were assayed with fecal specimens or bacteria cultures. Results: When ginseng extract was orally administered to rats fed with 2.5%, 5%, or 10% NUTRIOSE containing diets, the maximum plasma concentration ($C_{max}$) and area under the plasma concentration-time curve values of CK significantly increased in a NUTRIOSE content-dependent manner. NUTRIOSE intake increased glycosidase activity and CK formation in rat intestinal contents. The CK-forming activities of intestinal microbiota cultured in vitro were significantly induced by NUTRIOSE. Conclusion: These results show that prebiotic diets, such as NUTRIOSE, may promote the metabolic conversion of ginsenosides to CK and the subsequent absorption of CK in the gastrointestinal tract and may potentiate the pharmacological effects of ginseng.

• Journal of Ginseng Research
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• v.38 no.3
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• pp.220-225
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• 2014

An efficient in vitro protocol has been established for somatic embryogenesis and plantlet conversion of Korean wild ginseng (Panax ginseng Meyer). Wild-type and mutant adventitious roots derived from the ginseng produced calluses on Murashige and Skoog (MS) medium supplemented with 0.5 mg/L 2,4-dichlorophenoxyacetic acid and 0.3 mg/L kinetin; 53.3% of the explants formed callus. Embryogenic callus proliferation and somatic embryo induction occurred on MS medium containing 0.5 mg/L 2,4-dichlorophenoxyacetic acid. The induced somatic embryos further developed to maturity on MS medium with 5 mg/L gibberellic acid, and 85% of them germinated. The germinated embryos were developed to shoots and elongated on MS medium with 5 mg/L gibberellic acid. The shoots developed into plants with well-developed taproots on one-third strength Schenk and Hildebrandt basal medium supplemented with 0.25 mg/L 1-naphthaleneacetic acid. When the plants were transferred to soil, about 30% of the regenerated plants developed into normal plants.

• Archives of Pharmacal Research
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• v.27 no.6
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• pp.662-669
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• 2004

The highly water-soluble monomethoxypoly(ethyleneglycol) (mPEG) prod rugs of cyciosporin A(CsA) were synthesized. These prod rugs were prepared by initially preparing intermediate in the form of carbonate at the 3'-positions of CsA with chloromethyl chloroformate, in the pres-ence of a base to provide a 3'-carbonated CsA intermediate. Reaction of the CsA intermediate with mPEG derivative in the presence of a base provides the desired water-soluble prod rugs. As a model, we chose molecular weight 5 kDa mPEG in the reaction with CsA to give water soluble prodrugs. To prove that the prod rug is decomposed in the body to produce CsA, the enzymatic hydrolysis test was conducted using human liver homogenate at $37^{\circ}C$. The prodrug was decomposed in human liver homogenate to produce the active material, CsA, and the hydrolysis half-life ($t_{1/2}$) of the prodrug, KI-306 was 2.2 minutes at $37^{\circ}C$. However, a demon-stration of non-enzymatic conversion in pH 7.4 phosphate buffer was provided by the fact that the half-life ($t_{1/2}$) is 21 hours at 37$^{\circ}C$. The hydrolysis test in rat whole blood was also conducted. The hydrolysis was seen with half-life ($t_{1/2}$) of about 9.9, 65.0, 14.2, 3.4, 2.1 9.5, and 1.6 minutes for KI-306, 309, 312, 313, 315, 316, and 317, respectively. This is the ideal for CsA prodrug. The pharmacokinetic study of the prodrug, KI-306, in comparison to the commer-cial product (Sandimmune Neoral Solution) was also carried out after single oral dose. Each rat received 7 mg／kg of CsA equivalent dose. Especially, the prodrug KI-306 exhibits higher AUC and $C_{max}$ than the conventional Neoral. The AUC and $C_{max}$ were increased nearly 1.5 fold. The kinetic value was also seen with $T_{max}$ of about 1.43 and 2.44 hours for KI-306 and Neoral, respectively.

• Journal of Adhesion and Interface
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• v.20 no.4
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• pp.135-139
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• 2019

In this work, flame retardant acrylic emulsion pressure sensitive adhesives were newly polymerized combining phosphorous flame retardant monomer and acrylic monomer like butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, acrylic acid, and 2-hydroxyethyl methacrylate. The process of polymerization showed 100% of conversion at solid content of 65%, and viscosity of acrylic emulsion was increased up to 5500 cps when phosphorous flame retardant monomer was added into acrylic emulsion. The structure of flame retardant acrylic emulsion was identified using FT-IR and thermal properties like glass transition temperature (Tg) were checked by differential scanning calorimeter (DSC). Acrylic emulsion without phosphorous flame retardant monomer had Tg of -44.1℃ and peel strength of 2,100gf/inch, however, flame retardant acrylic emulsion showed maximum Tg (-31.4℃) and peel strength of 200gf/inch when 15 part of phosphorous flame retardant monomer was added. Flammability test was also conducted to confirm the application of flame retardant acrylic emulsion as the flame retardant addtive.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.41-46
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• 2005

Deinterlacing is the conversion from interlaced to progressive scan image that is considered to be 2 times image interpolation. In this paper, the simple and effective deinterlacing method is proposed based on the local gradient information of neighborhood pixels. In the proposed method, the weights for directions around the pixel to be interpolated are estimated, and the weighted sum for the neighborhood pixels is the final intensity value of the pixel to be interpolated. The proposed method has the structure suitable to practical implementation and can avoid the artifacts due to the wrong detection of edge direction. In the simulation, it showed improved subjective and objective performance than the ELA method and comparable performance compared with the variation of ELA method which has more complex structure and requires a couple of parameters that is determined by experience.

• Journal of the Korean Chemical Society
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• v.37 no.10
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• pp.867-873
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• 1993

Influences of crystallization time and $H_2O/Al_2O_3$ ratio of the reaction mixtures on the synthesis of AlPO$_4$-5 molecular sieve have been studied by X-ray powder diffraction, nitrogen adsorption, scanning electron microscope (SEM), and solid state $^{27}$Al magic angle spinning nuclear magnetic resonance (MAS NMR) techniques. The degree of crystallinity of AlPO$_4$-5 follows a sigmoid pattem as crystallization time increases. The induction period is shorter than 1 h when the crystallization process is carried out at 150$^{\circ}$C. The conversion of reactants to product, AlPO$_4$-5, can be clearly observed, and all of the determined physical properties change abruptly after about 2 h. It is found that increase in $H_2O/Al_2O_3$ ratio of the reaction mixtures not only changes the crystal morphology from aggregates to hexagonal single crystals, but also results in the formation of longer AlPO$_4$-5 crystals.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.1
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• pp.29-33
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• 2020

Despite the same system architecture and operation principle, Advanced Metering Infrastructure (AMI) and Internet of Things (IoT) are recognized as a heterogeneous system. This is due to the different object modeling and communication protocols used in smart meters and sensors. However, data interworking between AMI and IoT is expected to be inevitable in the future. In this paper, we propose Device Language Message Specification (DLMS) to Lightweight Machine to Machine (LwM2M) conversion model. The proposed interworking model can reduce the packet size by 46.5% compared to that of the encapsulation method.