• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.244-256
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• 2009

The psoralen-pyrimidine base complexes resulting from interstrand cross-linking through $C_4$-cycloaddition is studied by ab initio and DFT methods. The results indicate that in the case of the molecular complex formation between psoralens and pyrimidine base, the most probable photocycloadditions are 8-MOP< >Thy, Ps< >Cyt and Ps< >Thy. The geometries of photoadducts were optimized at the HF levels and ${\Delta}{G^{\circ}}$ were calculated. The photocycloadduct was inferred to be a C4-cycloaddition product with the stereochemistry of trans-syn 8-MOP< >Thy, trans-anti Ps(3, 4)< >Cyt, trans-anti Ps(12, 13)< >Cyt, trans-syn Ps(3, 4)< >Thy, trans-syn Ps(12, 13)< >Thy, trans-anti Ps(12, 13)< >Ps(12, 13), cis syn, cis anti Thy< >(3, 4)Ps(12, 13)< >Thy.

• Korean Journal of Environmental Biology
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• v.23 no.1
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• pp.52-56
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• 2005

Eight days grown barley seedlings were treated with dimethipin for 72 hours and then the content of chlorophyll and photosynthetic electron activities of isolated chloroplasts were investigated. At the treatment of 10/sup -5/ M dimethipin the content of chlorophyll was decreased to 33% at 72 hours. Seven days etiolated barley seedlings were exposed to the light while dimethipin was added. At the time of 48 hours' greening chlorophyll content was reduced to 43% at 10/sup -4/M dimethipin and the chlorophyll a/b ratio was increased. In photosynthetic electron transport the activity of PSⅡ+PSⅠ was decreased to 10% at 48 hours and 25% at 72 hours at 10/sup -4/ M dimethipin. In the treatment of 10/sup -4/ M dimethipin the activity of PSⅡ+PSⅠ, except water splitting system was inhibited to 16% at 48 hours and 27% at 72 hours. The activity of PSⅡ was inhibited to 8% at 24 hours, 13% at 48 hours and 18% at 72 hours at 10/sup -4/ M dimethipin. The activity of PSⅠ was inhibited to 4% at 24 hours, 8% at 48 hours and 10% at 72 hours at 10/sup -4/ M dimethipin. In the times of greening of 7 days etiolated barley seedlings the activities of PSⅡ+PSⅠ were reduced to 5, 10, 10 and 11 % at 6, 12, 24, and 48 hours, respectively, at 10/sup -4/ M dimethipin. On the other hand, the activity of PSⅡ+PSⅠ except water splitting system, was not inhibited at all incubated hours in 10/sup -4/M dimethipin and there were no clear changes of the activities of PSⅡ and PSⅠ as compared to the control. Therefore, it could be concluded that dimethipin inhibited the photosynthetic electron activity by affecting the function of chloroplast rather than the synthesis of chloroplast and the inhibited function of chloroplast seems to come from the severe decrease of chlorophyll content.

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1260-1264
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• 2005

Three new quaternary tantalum thiophosphates, $K_{0.18}TaPS_6,\;K_{0.28}TaPS_6,\;and\;Rb_{0.09}TaPS_6$ have been synthesized by using reactive alkali metal halide fluxes and structurally characterized by single crystal X-ray diffraction techniques. The crystal structures of $K_{0.18}TaPS_6,\;K_{0.28}TaPS_6,\;and\;Rb_{0.09}TaPS_6$ contain 3-dimensional open framework anions, $[TaPS_6]^{x-}$(x = 0.09, 0.18, 0.28) with the empty channel which disordered alkali metal cations, $K^+\;and\;Rb^+$ are located in. Crystal data: $K_{0.18}TaPS_6$, tetragonal, space group$I4_1$/acd (no. 142), a=15.874(3) $\AA$, c=13.146(4) $\AA$, V=3312.7(12) ${\AA}^3$, K, Z=16, R1=0.0545. Crystal data: $K_{0.28}TaPS_6$, tetragonal, space group $I4_1$/acd (no. 142), a=15.880(2) $\AA$, c=13.134(3) $\AA$, V=3312.1(10) ${\AA}^3$, Z=16, R1=0.0562. Crystal data: $Rb_{0.09}TaPS_6$, tetragonal, space group I41/acd (no. 142), a=15.893(3) $\AA$, c=13.163(4) $\AA$, V=3324.7(15) ${\AA}^3$, Z=16, R1=0.0432.

• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.1
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• pp.2925-2933
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• 1973

For the efficient utilization of farm machines on the inclined uqland, work performance in plowing, harrowing and terracing and critical workable gradients were tested on three farm machines which are 47 ps-farm tractor, 8 ps-power tiller and 5 ps-power tiller. The results of this study are summarized as follows; 1) The steeper the slope of the upland was the more inefficient the work performance of all machines was. 2) The critical workable gradients of the machines were proved as 14 for 47 ps-farm tractor, 12 for 8 ps-power tiller and 10 for 5ps-power tiller. 3) Plowing in the way of turning the furrow slices against the slope in order to build up terraces, the critical workable gradients were 8 for 47 ps-farm tractor and 8 ps-power tiller and 6 for 5 ps-power tiller. 4) Two-way plow is recommended for plowing with farm tractor on inclined upland, and high lug of tire would be good to prevent the slippage, and side valance-weight should be attached to power tiller for preventing its overturning.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.2
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• pp.190-198
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• 1996

The Neomycin resistant gene in transposon 5 (Tn5) was introduced into a mutant of Bradyrhizobium japonicum RJB 6 $str^rnal^r$ by conjugation. This marked strain was used in coinoculation of soybean with Pseudomonas fluorescens(Ps-3) and Bacillus subtilis(BCAC-4) and in antibiotic treatment of soybean for studying rate of nodule formation and growth promoting effect on soybean plant. When the marked strain RJB 6 $str^rnal^rneo^r$ with Ps-3, BCAC-4, and Ps-3 plus BCAC-4 was coinoculated into two soils, the recovery rate of the marked strain was 8.5, 4.3 and 2.9 percent in soybean cultivated soil, and 10.3. 6.0 and 5.0 percent in soybean uncultivated soil. The best growth promoting effect of coinoculation on soybean plant was found with the marked strain plus Ps-3. When the marked strain was inoculated into soybean with antibiotic treatment, the rate of nodule formation in soybean cultivated soil was between 12.5 and 25.4 percent, while that in soybean uncultivated soil was between 23.7 and 43.2 percent. The highest rate of nodule formation with the marked strain was found in streptomycin 1000 ppm treatment plot.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.22-26
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• 2005

Four male crossbred beef steers about 2 years old were used in a 4$\{times}$4 Latin square design to investigate the effect of pelleted sugarcane tops on voluntary feed intake, rumen fermentation and digestibility of nutrients. Experimental treatments were; Control (dried-chopped sugarcane tops (DCST)); PS1 (Pelleted sugarcane tops at 1 cm of diameter); PS2 (Pelleted sugarcane tops at 2 cm of diameter) and PS3 (Pelleted sugarcane tops at 3 cm of diameter). Roughage intake and total dry matter intake were 1.59, 1.62, 1.61, 1.63% BW and 2.09, 2.12, 2.11 and 2.13% BW in control, PS1, PS2 and PS3 treatments, respectively (p<0.05). Digestibility of DM, OM and CP were similar in control and PS3 treatment but there was significant difference (p<0.05) between control and PS1, PS2 treatments. Digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were 52.89, 50.01, 50.05 and 50.56% and 41.91, 39.96, 39.91 and 39.69% in control, PS1, PS2 and PS3, respectively (p<0.05). Total volatile fatty acids concentrations in rumen contents was 67.68, 65.93, 66.15 and 66.67 mM in control, PS1, PS2 and PS3, respectively (p<0.05). Even though, concentrations of acetate and butyrate (%) were significant different (p<0.05) but concentration of propionate (%) was not affected by treatments (p>0.05). Rumen pH, ammonia nitrogen and plasma urea nitrogen were significantly different (p<0.05) among treatments. From this experiment, it was found that dried-chopped sugarcane tops increased digestibility of nutrients whereas pelleted sugarcane tops increased feed intake in beef cattle. However, pelleted sugarcane tops at 3 cm of diameter did similar result in digestibility and rumen parameters with DCST. Therefore, it could be concluded that pelleting sugarcane top is an alternative way to improve the quality of sugarcane tops for use as ruminant roughage source.

• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.12-18
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• 2000

In order to artificially reduce the quinclorac residue in aqueous solution and soil, six potential photosensitizers were screened for their effectiveness in enhancing the photodegradation. The degraded amount of quinclorac in distilled water by sunlight was minor compared to that in the dark, indicating that there was little direct photolysis. The photodegradation ratio of quinclorac in methanol was 40.3%. Whereas, the ratios in the presence of photosensitizers PS-1 (aromatic ketone), PS-3 (polycyclic quinone), and PS-6 (inorganic semiconductor) were 96.6, 72.7, and 95.7%, respectively, showing the most photosensitizing effects. In sand, PS-3 was more effective than any other photosensitizer PS-1 (19.6%), PS-3 (64.1%) and PS-6 ($17.9{\sim}19.4%$). five photoproducts of quinclorac in methanol were identified by GC-MS and quinclorac added with the photosensitizer PS-1 gave three photoproducts. Photoproducts with an aldehyde group formed in methanol were confirmed by the reduction of sodium 3,5-dinitrosalicylate in the Lindsay's method. E. crus-galli war. oryzicola was not controlled by the quinclorac residues photodegraded at tile concentrations higher than 30 ppm of the photosensitizer PS-3 in a flooded rice paddy soil. These results indicate that the quinclorac residues in aqueous solution and soil can be degraded efficiently by tile photosensitizers PS-1, PS-3, and PS-6.

• Journal of Soil and Groundwater Environment
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• v.22 no.2
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• pp.17-25
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• 2017

The efficiency and mechanism of electrochemical phenol oxidation using persulfate (PS) and nanosized zero-valent iron (NZVI) were investigated. The pseudo-first-order rate constant for phenol removal by the electrochemical/PS/NZVI ($1mA^*cm^{-2}/12$ mM/6 mM) process was $0.81h^{-1}$, which was higher than those of the electrochemical/PS and PS/NZVI processes. The electrochemical/PS/NZVI system removed 1.5 mM phenol while consuming 6.6 mM PS, giving the highest stoichiometric efficiency (0.23) among the tested systems. The enhanced phenol removal rates and efficiencies observed for the electrochemical/PS/NZVI process were attributed to the interactions involving the three components, in which the electric current stimulated PS activation, NZVI depassivation, phenol oxidation, and PS regeneration by anodic or cathodic reactions. The electrochemical/PS/NZVI process effectively removed phenol oxidation products such as hydroquinone and 1,4-benzoquinone. Since the electric current enhances the reactivities of PS and NZVI, process performance can be optimized by effectively manipulating the current.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.4
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• pp.282-293
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• 2018

The heading response of rice varieties is determined by the combined effects of their basic vegetative phase (BVP), photoperiod-sensitivity (PS), and thermo-sensitivity (TS). This study was performed to analyze the effect of differences among heading ecotypes of rice on their heading response in the field. To do this, we investigated the heading response of 15 varieties grown under different day-length and temperature conditions in a phytotron. The characteristics of heading ecotypes were compared to the heading responses in the field-grown rice varieties that were used in the phytotron experiments. The ranges of these characteristics across the 15 varieties were 18 - 35 days for BVP, 12 - 61 days for PS, and 12 - 35 days for TS. In comparisons of coupled varieties that differed only in a single trait among BVP, PS, and TS, the variety with the longer BVP and that with the higher PS had a longer period from sowing to heading (DTH), while the variety with the higher TS had a shorter DTH. The comparative magnitude of DTH in the coupled varieties followed the PS trait when BVP and PS were involved, the BVP trait when BVP and TS were involved, and the PS trait when PS and TS were involved in the heading response of field-grown rice. When comparing the coupled varieties with different traits of the three examined factors, the heading response was consistent with the PS trait. The DTH in all 15 varieties was significantly correlated with the PS, and the DTH in 9 selected varieties with a relatively small PS was correlated with BVP. The reduced DTH of rice in the July 10 seeding treatment compared to those in the June 25 and May 11 seeding treatments was positively associated with PS, but not with TS. We concluded that the heading response of rice varieties under natural conditions in Korea is mainly governed by the PS trait and is also greatly affected by the BVP trait when the PS is small.

• Biomolecules & Therapeutics
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• v.12 no.2
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• pp.79-84
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• 2004

02PS15 extracts (BuOH, $H_2O$, and crude extracts) significantly inhibited IL-4 and IL-6 secretion from the phytohemagglutinin (PHA)-plus phorbol 12-myristate 13-acetate (PMA)-induced peripheral blood mononuclear cleas (P<0.05). 02PS15 extracts (BuOH and crude extracts) also significantly inhibited the histamine release from rat peritoneal mast cells (P<0.05). Significant reduced levels (P<0.05) of PMA- and A23187-induced IL-8 were observed in the human mast cell line, HMC-1, with O2PS15 extracts (BuOH and crude extracts). 02PS15 extracts (BuOH and crude extract) downregulated the expression of IL-6 and IL-8 in the activated HMC-1. These results suggest that O2PS15 has the inhibitory effect of atopic allergic reaction anil this might be useful for clinical application to treat several allergic diseases such as atopic dermatitis.