• Environmental Engineering Research
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• v.22 no.4
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• pp.347-355
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• 2017

This study investigated how the combined changes in environmental conditions and nitrogen (N) deposition influence the mineralization processes and carbon (C) dynamics of wetland soil. For this objective, we conducted a growth chamber experiment to examine the effects of combined changes in environmental conditions and N deposition on the anaerobic decomposition of organic carbon and the emission of greenhouse gases from wetland soil. A chamber with elevated $CO_2$ and temperature showed almost twice the reduction of total decomposition rate compared to the chamber with ambient atmospheric conditions. In addition, $CO_2$ fluxes decreased during the incubation under the conditions of ambient $CO_2$ and temperature. The decrease in anaerobic microbial metabolism resulted from the presence of vegetation, which influences the litter quality of soils. This can be supported by the increase in C/N ratio over the experimental duration. Principle component analysis results demonstrated the opposite locations of loadings for the cases at the initial time and after three months of incubation, which indicates a reduction in the decomposition rate and an increasing C/N ratio during the incubation. From the distribution between the decomposition rate and gas fluxes, we concluded that anaerobic decomposition rates do not have a significantly positive relationship with the fluxes of greenhouse gas emissions from the soil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.1
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• pp.64-69
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• 1988

Young barley plants (Hordeum vulgare) were exposed to $^{14}$ Co$_2$ for 10 and 30 minutes. Leaves were harvested and extracted for aqueous soluble metabolites which were fractionated into amino acids, sugars, sugar phosphates and organic acids. It was found that both 10 and 30 minute incubation periods had similar quantities of label but differed in the quality and quantity. It was also found that the neutral fraction (sugars, phosphate esters and organic acids) had 4.5 times more label than the amino acid fraction at 10 minutes and only about 1.7 times at 30 minutes. Label increased moderately from 10 minutes in the sugar fraction where there was a large increase in the amino acid fraction, both qualitatively and quantitatively. Photosynthetic rate was found to be quite different when the 10 minute incubation and the 30 minute incubation were compared (0.125 vs 0.034 and 0.042 $\mu$mole co$_2$/mg chlorophy 11/min respectively).

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.104-111
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• 2000

The study war carried out to evaluate the characteristics of inorganic phosphate factions in soil mixed with paper mill sludge compost(PMSC). The experiments were conducted by an incubation test. For the incubation test, application rates of PMSC to soil were 0, 2, 8, and 16%. Water content of the samples mixed with PMSC were adjusted to 10% and 15% and incubating temperatures of the samples were kept at $4^{\circ}C$ and $30^{\circ}C$, respectively. The results can be concluded as follows; pH increased depending on the higher rates of PMSC application to the soil during the incubation tests, because calcium content was $4.9cmol_c/kg$ and contents of nutrients were high. When the application rates of PMSC were increased Saloid-P and Fe-P decreased, while Al-P and Ca-P in soil increased during the incubation tests.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.454-458
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• 1997

To develop a yellow pigment for a food-additive, a strain producing a water-soluble yellow pigment was isolated from phylloplane of tree leaf. The strain PY123 was identified a Bacillus sp. based on morphological and biochemical characterization such as a bacillus form, mortility, spore formation, Gram positive, and catalase production. The pigment production of the strain PY123 was increased about 3 times in patato broth containing 1% sucrose and 0.1 mM CoCl$_{2}$ than in only potato broth after incubation at 30$circ$C, for 2 days. When 0.1 mM CoCl$_{2}$, was added in potato broth containing 1% sucrose at late log phase during incubation of the strain PY123, cell growth was not inhibited, and the period at maximal pigment production of the strain PY123 was about 12hrs faster than in potato broth containing 1% sucrose and 0.1 mM CoCl$_{2}$, simultaniously.

• Journal of Pharmaceutical Investigation
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• v.40 no.4
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• pp.251-254
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• 2010

The formation of acylated peptide impurities in poly(lactide-co-glycolide) (PLGA) formulations is one of the major challenges to the development of successful sustained-release product. Octreotide, synthetic analogue of somatostatin, has been identified to be acylated in PLGA microsphere formulations. The purpose of this study was to investigate the pH effect on the formation of acylated octreotides by PLGA. In the incubation with PLGA in 0.1 M phosphate buffer at pH 7.4, approximately 98% of octreotide adsorbed to PLGA through 14 days and 66.3% of acylated octreotides were produced after 42 days, whereas the interaction of octreotide with PLGA was significantly inhibited in the incubation at pH 4, in which the acylated octreotides were observed to be 9.2% after 42 days. In the interaction study at pH 4.1-7.4, the production of acylated octreotides was demonstrated to be dependent on environmental pH. Below pH 5.0, the acylation of octreotide was significantly inhibited. This study indicates that the pH is the major factor for the formation of acylated octreotide in PLGA formulations.

• Journal of Dairy Science and Biotechnology
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• v.29 no.2
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• pp.17-23
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• 2011

The focus of this study was to clarify the relation between the nitric oxide (NO) production and cytokine expression including tumor necrosis factor-${\alpha}$ (TNF) and interleukin-6 (IL-6), and also investigated the effect of G-NANA (N-acylneuraminic acid isolates from glycomacropeptide) or S-NANA (Synthetic N-acylneuraminic acid) on LPS stimuli from RAW264.7 cell. The NANA is the predominant sialic acid found in mammalian cells and G-NANA is isolation of GMP (GMP is a valuable bioactive peptide with a varying degree of glycosylation including sialic acid). The lipopolysaccharide (LPS) of Gram-negative bacteria induces the expression of cytokines and potent inducers of inflammatory cytokines such as TNF-${\alpha}$ and IL-6. In this experiment, upon stimulation with increasing concentrations of chitosan, the LPS-stimulated TNF-${\alpha}$ and IL-6 secretion was significantly recovered with in the incubation media of RAW264.7 cells. Consistently, RT-PCR with mRNA and immunoblot analysis with anti-cytokine antiserum including TNF-${\alpha}$ and IL-6 showed that the amount of TNF-${\alpha}$ and IL-6 secretion in the incubation media recovered with the concentration of chitosan. The LPS-stimulated NO secretion was significantly recovered with in the 6 and 12 h incubation media of RAW264.7 cells, too. The recovery effect of G-NANA on IL-6 and NO secretion may be induced via the stimulus of TNF-${\alpha}$ in RAW264.7 cell. These results once again suggest that G-NANA may have the anti-inflammatory effect via the stimulus of TNF-${\alpha}$ in the LPS-stimulated inflammation in RAW264.7 cells.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.554-561
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• 2017

Under the projected global warming, release of carbon as $CO_2$ through soil organic matter decomposition is expected to increase. Therefore, accurate measurement of $CO_2$ released from soil is crucial in understanding the soil carbon dynamics under increased temperature conditions. Sodium hydroxide (NaOH) traps are frequently used in laboratory soil incubation studies to measure soil respiration rate, but decreasing $CO_2$ gas solubility with increasing temperature may render the reliability of the method questionable. In this study, the influences of increasing temperature on the $CO_2$ capture capacity of NaOH traps were evaluated under $5{\sim}35^{\circ}C$ temperature range at $10^{\circ}C$ interval. Two closed-chamber experiments were performed where NaOH traps were used to capture $CO_2$ either released from acidified $Na_2CO_3$ solution or directly injected into the chamber. The sorption of ambient $CO_2$ within the incubators into NaOH traps was also measured. The amount $CO_2$ captured increased as temperature increased within 2 days of incubation, suggesting that increased diffusion rate of $CO_2$ at higher temperatures led to increases in $CO_2$ captured by the NaOH traps. However, after 2 days, over 95% of $CO_2$ emitted in the emission-absorption experiment was captured regardless of temperature, demonstrating high $CO_2$ absorption efficiency of the NaOH traps. Thus, we conclude that the influence of decreased $CO_2$ solubility by increased temperatures is negligible on the $CO_2$ capture capacity of NaOH traps, supporting that the use of NaOH traps in the study of temperature effect on soil respiration is a valid method.

• KSBB Journal
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• v.14 no.3
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• pp.315-321
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• 1999

The relationships between the explosive 2,4,6-trinitrotoluene (TNT) degradation by Stenotrophomonas maltophilia and several relevant physicochemical environmental parameters were examined. At neutral pH of the cultures, the degradation of TNT proceeded to completion, whereas only about 50% of TNT was utilized when the cultures were adjusted to acidic pH. The effect of various co-substrates (e.g., glucose, fructose, acetate, citrate, succinate) on the degradation of TNT by the test culture of S. maltophilia was evaluated. The results indicated that, among the various co-substrates studies, the test culture that received 2 mM fructose degraded 100 mg/L of TNT completely within 20 days of incubation at ambient temperature, whereas partial degradation of TNT was observed in the test culture with acetate, citrate, or succinate as a co-substrate, respectively. In fact, fructose was the best co-substrate for TNT degradation in this experiment. The effect of supplemented nitrogens [e.g., (NH$_4$)$_2$,SO$_4$, NH$_4$Cl. urea] on the TNT degradation was monitored. All supplemented nitrogens in this study were inhibitory to TNT degradation. Addition of 1% Tween80 accelerated TNT degradation, and showed complete degradation of TNT within 8 days of incubation. Addition of yeast extract resulted higher growth yields, based on turbidity measurement, but it inhibited TNT degradation.

• YAKHAK HOEJI
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• v.55 no.2
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• pp.98-105
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• 2011

To search the minimum structural requirement of tricyclic isoxazole analogues (1~30) as new class potent antidepressant, thee-dimensional quanti- tative-structure relationship (3D-QSAR) models between substituents ($R_1{\sim}R_5$) of tricyclic isoxazoles and their antidepressant activity against medetomidine-induced loss of righting were performed and discussed quantitatively using comparative molecular field analysis (CoMFA) and comparative molecular similarity indies analysis (CoMSIA) methods. The correlativity and predictability ($r^2$=0.484 and $q^2$=0.947) of CoMSIA-2 model were higher than those of the rest models. The inhibitory activity against medetomidine-induced loss of righting was dependent on electrostatic field (43.4%), hydrophobic field (35.3%), and steric field (21.2%) of tricyclic isoxazoles. From the CoMSIA-2 contour maps, it is predicted that the antidepressant activity of potent antidepressants against medetomidine-induced loss of righting will be able to increase by the substituents ($R_1{\sim}R_5$) which were in accord with CoMSIA field.

• YAKHAK HOEJI
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• v.55 no.2
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• pp.91-97
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• 2011

To search a new anti-depressant agents against para-chloroamphetamine-induced excitation, three dimensional quantitative-structure relationships (3D-QSAR) models between structure of 3a,4-dihydro-3H-[1]-benzopyronao[4,3]isoxazoles (1-30) and thieir inhibitory activity against para-chloroamphetamine-induced excitation were performed and discussed quantitatively using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods. From these basis on the findings, the optimized CoMSIA-2F model ($q^2$=0.793 and $r^2$=0.952) showed the best statistical results. And also, it is found that the para-chloroamphetamine inhibitory activity from the optimized CoMSIA-2F model was dependent on steric field (35.2%) and electrostatic field (64.8%) of tricyclic isoxazoles. Particularly, it is predicted that the inhibitory activity against para-chloroamphetamine-induced excitation will be able to increase by the designed compounds from the CoMSIA-2F model.