• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.359-365
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• 2021

BACKGROUND: Prohexadione-calcium (PC) is a plant growth regulator of cyclohexanedione family acting on inhibiting gibberellin biosynthesis and has been used to regulate shoot elongation of turfgrass in the golf course during the summer season. This study was conducted to investigate the effects of PC on the inhibition of shoot elongation, growth, and nitrogen uptake in Zoysia matrella. METHODS AND RESULTS: Treatments were as follows; non-treatment, control (TE 0.01 a.i. g/m²/100 mL), 0.0025PC (PC 0.0025 a.i. g/m²/100 mL), 0.005PC (PC 0.005 a.i. g/m²/100 mL), 0.01PC (PC 0.01 a.i. g/m²/100 mL) and 0.02PC (PC 0.02 a.i. g/m²/100 mL). Visual quality and chlorophyll content were not significantly different. As compared to non-treatment, shoot length and clipping yield in 0.005PC, 0.01PC and 0.02PC treatments were decreased by 29-36% and 65-82%, respectively, and those of 0.0025PC were not significantly different. N uptake of Z. matrella after applying PC was decreased by 28.9-77.8% than that of non-treatment. Inhibition effects of PC treatment in Z. matrella were not significantly different from those of control. CONCLUSION(S): These results indicated that the application of prohexadione calcium inhibited shoot elongation, clipping yield and N uptake amount in Z. matrella, and trinexapac-ethyl could be replaced with prohexadione-calcium in turfgrass management.

• Journal of Soil and Groundwater Environment
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• v.24 no.6
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• pp.26-32
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• 2019

An analysis of groundwater quality is significant for monitoring and managing water contamination and groundwater system. For the purpose of those, the geochemical characteristics of groundwater were studied over the concern for water quality, water type and origin of nitrate nitrogen. Total colony counts were detected in 11 out of 20 samples, and the average value was 31.73 CFU/ml. Range and average of NO₃-N concentrations were 0.9~24.0 mg/L and 8.3 mg/L. All groundwater types were found to be Ca²⁺-HCO₃^-. The range and average of NO₃-N were 0.2~17.4 mg/L and 8.7 mg/L, and those of δ¹⁵N were 1.7~8.9‰, and 5.0‰. Careful consideration is required for evaluating the origin of nitrogen when NO₃-N concentration is low. In general, noticeable difference between rockbed and alluvial water was not found. The ranges of nitrate origins by chemical fertilizer, livestock manure and domestic sewage, and natural soil were 29.6~76.4%, 14.2~58.9% and 2.6~7.0%, and the average values of those were 57.4%, 37.4%, and 5.3%, respectively. Origin of nitrate was affected by more chemical fertilizer than the other parameters. Rockbed water was more affected by chemical fertilizer than alluvial water.

• Environmental Engineering Research
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• v.25 no.2
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• pp.186-196
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• 2020

Pillared clays with Zr and Fe/Cu/Zr polycations have been prepared from natural clays found in large deposits of Kazakhstan and assessed as catalysts for the catalytic wet peroxide oxidation (CWPO), using 4-nitrophenol (4-NP) as model compound. The performance of the catalysts was followed by measuring the concentration of 4-NP, H₂O₂ and the total organic carbon (TOC), considering C_4-NP = 5 g L^-1, $C_{H_2O_2}$ = 17.8 g L^-1, C_cat = 2.5 g L^-1, initial pH = 3.0 and T = 50℃. At those selected conditions, the pillared clays showed higher activity than natural clays in the CWPO of 4-NP. The conversion of the model pollutant was complete when Fe/Cu/Zr-PILCs were used, with the TOC removal reaching 78.4% after 24 h with the best Fe/Cu/Zr-PILC. The H₂O₂, 4-NP and TOC time-evolution was well described by a kinetic model based on TOC lumps in three blocks, considering the initial TOC (corresponding to 4-NP), the production of oxidizable intermediates and the formation of refractory products.

• Journal of Microbiology and Biotechnology
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• v.30 no.4
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• pp.533-539
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• 2020

A quantitative real-time polymerase chain reaction (QPCR) was applied to estimate biokinetic coefficients of Clostridium cadaveris and Clostridium sporogenes, which utilize protein as carbon source. Experimental data on changes in peptone concentration and 16S rRNA gene copy numbers of C. cadaveris and C. sporogenes were fitted to model. The fourth-order Runge-Kutta approximation with non-linear least squares analysis was employed to solve the ordinary differential equations to estimate biokinetic coefficients. The maximum specific growth rate (μ_max), half-saturation concentration (K_s), growth yield (Y), and decay coefficient (K_d) of C. cadaveris and C.sporogenes were 0.73 ± 0.05 and 1.35 ± 0.32 h^-1, 6.07 ± 1.52 and 5.67 ± 1.53 g/l, 2.25 ± 0.75 × 10¹⁰ and 7.92 ± 3.71 × 10⁹ copies/g, 0.002 ± 0.003 and 0.002 ± 0.001 h^-1, respectively. The theoretical specific growth rate of C. sporogenes always exceeded that of C. cadaveris at peptone concentration higher than 3.62 g/l. When the influent peptone concentration was 5.0 g/l, the concentration of C.cadaveris gradually decreased to the steady value of 2.9 × 10¹⁰ copies/ml at 4 h Hydraulic retention time (HRT), which indicates a 67.1% reduction of the initial population, but the wash out occurred at HRTs of 1.9 and 3.2 h. The 16S rRNA gene copy numbers of C. sporogenes gradually decreased to steady values ranging from 1.1 × 10¹⁰ to 2.9 × 10¹⁰ copies/ml. C. sporogenes species was predicted to wash out at an HRT of 1.6 h.

• Journal of the Korean Wood Science and Technology
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• v.50 no.4
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• pp.283-298
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• 2022

Wood has always been used for various day-to-day applications such as interior or exterior construction materials, and household products. However, it can undergo photodegradation and discoloration by environmental factors including ultraviolet (UV) light, and thus has shortened its service life. Bleaching or delignification of wood surfaces is a suitable solution to stabilize wood against weathering by UV because these techniques can alter or remove the chromophores in lignin, which is a main factor of wood discoloration. To improve the color stability of wood surface according to the lifespan, surface delignification was conducted using peracetic acid (PAA) and hydrogen peroxide (HP) on the woods of Larix kaempferi and Quercus mongolica. After the PAA treatment, L^* increased considerably from 60-70 to 90-95. Furthermore, wood surface color did not change significantly after UV exposure. The color differences (𝜟E^*) between before and after PPA treatment of wood showed the 4.8-12.2 of L. kaempferi, and 1.7-3.7 of Q. mongolica, respectively. The lignin-related peaks in Fourier transform infrared spectroscopy (FT-IR) spectra disappeared with increased duration of PAA treatment. These results confirmed that the lignin component was partially or completely removed after the PAA treatment; the color differences (𝜟E^*) clearly showed that there was a reduction in redness (a^*) and yellowness (b^*), and an increase in lightness (L^*) owing to the removal of lignin. Based on these results, this study demonstrated that the partial removal of lignin from wood surfaces is a fundamental method for resolving photo-degradation.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.27 no.1
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• pp.26-36
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• 2024

Purpose: We investigated the role of CD8⁺T cells as host immune factors in pediatric patients with Helicobacter pylori gastritis. Methods: Gastric mucosal tissue and blood samples were collected from 39 children, including 11 children with H. pylori infection and 28 children as controls. Anti-CD8 and anti-T-bet antibodies were used for immunohistochemistry of the gastric mucosa. For the cell surface and intracellular staining, peripheral blood mononuclear cells were stained with anti-IL7Rα, anti-CX3CR1, anti-CD8, anti-T-bet, and anti-IFN-γ antibodies. Cytokines of sera such as tumor necrosis factor alpha (TNF-α) and CX3CL1 were analyzed using enzyme- linked immunosorbent assay (ELISA). Results: In the immunohistochemistry of gastric mucosa, the frequency of CD8⁺ and T-bet⁺ T cells cells was higher in the H. pylori-positive group than in the control group (26.9± 7.8% vs. 16.9±3.3%, p<0.001; 5.0±2.5% vs. 2.2±0.7%, p=0.001). Between the control and H. pylori-positive groups, the frequency of IL-7Rα^lowCX3CR1⁺ CD8⁺ and T-bet⁺ INF-γ⁺ CD8⁺ T cells were not significantly different between surface and intracellular staining, respectively (40.4±24.0% vs. 38.2±17.8%, p=0.914; 40.4±24.0% vs. 38.2±17.8%, p=0.914). In the ELISA, no significant differences in TNF-α and CX3CL1 concentrations were observed between the control and H. pylori-positive groups (34.3±12.1 pg/mL vs. 47.0±22.6 pg/mL, p=0.114/0.5± 0.1 pg/mL vs. 0.5±0.1 pg/mL, p=0.188). Conclusion: CD8⁺ T and Th1 cells, which secrete IFN-γ, might play important roles in the mucosal immunity of the stomach in children with H. pylori infection.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.325-331
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• 2022

One of the most important factors in predicting tomato growth and yield is the leaf area. Estimating leaf area accurately is the beginning of an effective tomato plant growth assessment model. To this end, this study was conducted to identify the most effective model for estimating plant leaf area through the measurement of tomato plant leaves. Leaf area (LA), leaf length (L), leaf width (W), and lamina length (La) were measured for all leaves of 5 plants at two-week intervals. The correlation between LA and tomato-leaf-independent variables showed a strong positive relationship with the formulas La × W, L × W, La + W, and L + W. For LA estimation, a linear model using the formula LA = a + b (La² + W²) gave the most accurate estimation (R² = 0.867, RMSE = 88.76). After examining the positions of upper, middle, and lower leaves from September to December, the coefficient of determination (R²) values for each model were 0.878, 0.726, and 0.794 respectively. The most accurate estimation came from the model that used the upper leaves of the plants. The high accuracy of the upper-leaf-based model is judged by the 50% defoliation performed by farmers after October.

• Nonlinear Functional Analysis and Applications
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• v.26 no.2
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• pp.331-345
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• 2021

Let p(z)be a polynomial of degree n. Then Bernstein's inequality [12,18] is $${\max\limits_{{\mid}z{\mid}=1}}\;{\mid}p^{\prime}(z){\mid}\;{\leq}\;n\;{\max_{{\mid}z{\mid}=1}{\mid}(z){\mid}}$$. For q > 0, we denote $${\parallel}p{\parallel}_q=\{{\frac{1}{2{\pi}}}{\normalsize\displaystyle\smashmargin{2}{\int\nolimits_{0}}^{2{\pi}}}\;{\mid}p(e^{i{\theta}}){\mid}^qd{\theta}\}^{\frac{1}{q}}$$, and a well-known fact from analysis [17] gives $${{\lim_{q{\rightarrow}{{\infty}}}}\{{\frac{1}{2{\pi}}}{\normalsize\displaystyle\smashmargin{2}{\int\nolimits_{0}}^{2{\pi}}}\;{\mid}p(e^{i{\theta}}){\mid}^qd{\theta}\}^{\frac{1}{q}}={\max\limits_{{\mid}z{\mid}=1}}\;{\mid}p(z){\mid}$$. Above Bernstein's inequality was extended by Zygmund [19] into L^q norm by proving ║p'║_q ≤ n║p║_q, q ≥ 1. Let p(z) = a₀ + ∑ⁿ_𝜈=𝜇 a_𝜈z^𝜈, 1 ≤ 𝜇 ≤ n, be a polynomial of degree n having no zero in |z| < k, k ≥ 1. Then for 0 < r ≤ R ≤ k, Aziz and Zargar [4] proved $${\max\limits_{{\mid}z{\mid}=R}}\;{\mid}p^{\prime}(z){\mid}\;{\leq}\;{\frac{nR^{{\mu}-1}(R^{\mu}+k^{\mu})^{{\frac{n}{\mu}}-1}}{(r^{\mu}+k^{\mu})^{\frac{n}{\mu}}}\;{\max\limits_{{\mid}z{\mid}=r}}\;{\mid}p(z){\mid}}$$. In this paper, we obtain the L^q version of the above inequality for q > 0. Further, we extend a result of Aziz and Shah [3] into L^q analogue for q > 0. Our results not only extend some known polynomial inequalities, but also reduce to some interesting results as particular cases.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.435-440
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• 2004

The thiophene or furan-containing hexadentate ligands 1, 12-bis (2-theophene )-2,5,8,ll-tetraazadodecane(Thiotrien ㆍ 4HCl) and 1,12-bis (2-furan)-2,5,8,11-tetraazadodecane(Furatrienㆍ4HC1) were synthesized as their tetrahydrochloride salt and characterized by EA, IR, NMR, and Mass spectrum. Their protonation constants (logK$_{nH}$) and stability constants (logK$^{M}_{L}$ for Cd$^{2+}$, Pb$^{2+}$, $Zn^{2+}$ and Cu$^{2+}$ ions were determined in aqueous solution by potentiometry and compared with 1, 12-bis(2-pyridyl)-2,5,8, 11-tetra-azadodecane(Pytrien) of pyridyl-containing ligand. The effect stability constants of ligands and metal ion for removal of heavy metals in aqueous solution were described.

• Journal of People, Plants, and Environment
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• v.24 no.5
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• pp.499-507
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• 2021

Background and objective: This study was carried out to develop an effective technique for raising seedlings of Veronica pyrethrina Nakai, a native plant species in the Korean Peninsula, in plug trays. Methods: To investigate the optimum plug cell size and sowing media, we sowed seed in to plug trays with 34, 21, and 10 mL cells and filled with a commercial horticultural substrate and mixtures of peatmoss and perlite in 1:1, 3:1, and 4:1 ratios. Fertilization levels were set at 0, 500, 1000 and 2000 mg·L^-1. Results: Plug cell size did not significantly influence the seedling growth of V. pyrethrina. By substrate type, the growth rate was highest in the horticultural substrate, followed by 4:1, 3:1, and 1:1. Growth by fertilization level was higher in all fertilized treatment groups than in the control group, and there was no difference among 500, 1000, and 2000 mg·L^-1. Conclusion: The results of this study proved that it is most suitable for raising seedlings of V. pyrethrina to sow the seeds in a 10 mL cell plug tray filled with horticultural substrates, and apply fertilizers with less than 500 mg·L^-1 concentration.