• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.322-329
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• 1999

The hydrodynamic theory of dentin sensitivity states that movement of tubular contents or tubular fluid, in either direction of dentinal tubule, causes dentin sensitivity. A corollary of that theory is that anything that can decrease dentinal fluid movement or dentin permeability should decrease dentin sensitivity. A wide variety of physicochemical methods have been used to reduce the permeability and sensitivity of exposed dentin. The purpose of this study was to evaluate the ability of 4 kinds of clinical desensitizing agents(2% NaF, 30% Potassium oxalate, MS Coat$^{(R)}$, Tubulitec system$^{(R)}$) to reduce the rate of fluid flow through dentin in vitro. Sixty coronal dentin discs, 1mm in thickness, were prepared from extracted third molars, free from decay and wear. Dentin discs were treated with 3% EDTA(Tubulicid Plus$^{(R)}$(Dental Therapeutics AB, Sweden)) to remove the smear layer and debris occluding the tubular orifices. After placing the discs in a split chamber device, the rate at which physiologic saline solution could filter across dentin under 150cm $H_2O$ hydrostatic pressure was measured. The occlusal side of the discs were then treated with MS Coat$^{(R)}$, 2% NaF, Tubulitec system$^{(R)}$, and 30% Potassium oxalate, and the filter ratio of the saline solution was measured again. The following conclusions were drawn : 1. Hydraulic conductance which was measured after the application of desensitizing agents was decreased in all the groups(p<0.05). 2. % change of hydraulic conductance was compared but no significant difference was found among the four desensitizing agents(p>0.05). 2% NaF, 30% Potassium oxalate, MS Coat$^{(R)}$ and Tubulitec system$^{(R)}$ decreased the permeability of dentin. It is considered that above four agents can be used in treating the hypersensitive teeth.

• The Journal of Advanced Prosthodontics
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• v.1 no.1
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• pp.1-5
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• 2009

STATEMENT OF PROBLEM. Poor wettability of denture relining materials may lead to retention problems and patient discomfort. PURPOSE. Purpose of this study is to compare and evaluate wettability of nine denture relining materials using contact angle measurements under air and water storage over time. MATERIAL AND METHODS. Nine denture relining materials were investigated in this study. Two heat-curing polymethyl-methacrylate(PMMA) denture base materials: Vertex RS, Lang, one self-curing polyethyl-methacrylate(PEMA) chairside reline resin: Rebase II, six silicone relining materials: Mucopren soft, Mucosoft, $Mollosil^{{R}}$ plus, Sofreliner Touch, GC $Reline^{TM}$ Ultrasoft, Silagum automix comfort were used in this experiment. Contact angles were measured using high-resolution drop shape analysis system(DSA 10-MK2, KRUESS, Germany) under three conditions(in air after setting, 1 hour water storage, and 24 hours water storage). Nine materials were classified into three groups according to material composition(Group 1: PMMA, Group 2: PEMA, Group 3: Silicone). Mean values of contact angles were compared using independent samples t-test and one-way ANOVA, followed by a Scheffe's post hoc analysis($\alpha$=0.01). RESULTS. Contact angles of materials tested after air and water storage increased in the following order: Group 1(PMMA), Group 2(PEMA), Group 3(Silicone). Heat-cured acrylic denture base resins had more wettability than silicone relining materials. Lang had the highest wettability after 24 hours of water storage. Silicone relining materials had lower wettability due to their hydrophobicity. Wettability of all denture relining materials, except Rebase II and $Mollosil^{{R}}$ plus, increased after 24 hours of water storage. CONCLUSIONS. Conventional heat-cured resin showed the highest wettability, therefore, it can be suggested that heat-cured acrylic resin is material of choice for denture relining materials.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.407-412
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• 1985

The effect of potash applied with different sources of nitrogen was experimented in pot soil culture on chinese cabbage (Brassica Pekinensis Rupr, Var. Fall 1984: Sammi Garak, Spring 1985: Jungang Summer lab.) in the fall, 1984 and in the spring, 1985. Results obtained are as follows; 1. Ammonium nitrate increased the yield of chinese cabbage more than urea did, and the effect of yield increase by ammonium nitrate was greater in the fall cultivation than in the spring. 2. The yield of chinese cabbage was positively correlated with the contents of K in the first (May 17, 1985) and second (June 9, 1985) thined cabbages (dry matter). It was also positively correlated with $NO_3-N$ content of the first thined cabbage and with K/Ca+Mg m.e, ratio of outer leaves of the harvested (June 27, 1985) cabbage, but negatively affected with Mg content of the outer leaves. 3. Correlations between K and $NO_3-N$ contained in the dry matter of first and second thined, and inner leaves of the harvested cabbage were learnt to be $r;0.9998^{**}$, r;0.4439, and $r;-0.7135^*$ respectively. The higher $NO_3-N$ content in the inner leaves of harvested cabbage was observed at K omitted ammonium nitrate plot where K was deficient, Ca and Mg contents were low. 4. The nutrient absorption and growth of chinese cabbage may take the following process. Nitrate nitrogen increases vegetative growth of the plant with enhanced K uptake and movement in to inner leaves and followed by replacement of Ca uptake and finally Mg uptake and its movement in to inner leaves.

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.379-386
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• 2011

The objective of this work was to investigate the ability of the plant growth-promoting rhizobacterium Pseudomonas aureofaciens 63-28 to induce plant defense systems, including defense-related enzyme levels and expression of defense-related isoenzymes, and isoflavone production, leading to improved resistance to the phytopathogen Rhizoctonia solani AG-4 in soybean seedlings. Seven-day-old soybean seedlings were inoculated with P. aureofaciens 63-28, R. solani AG-4, or P. aureofaciens 63-28 plus R. solani AG-4 (P+R), or not inoculated (control). After 7 days of incubation, roots treated with R. solani AG-4 had obvious damping-off symptoms, but P+R-treated soybean plants had less disease development, indicating suppression of R. solani AG-4 in soybean seedlings. Superoxide dismutase (SOD) and catalase (CAT) activities of R. solani AG-4-treated roots increased by 24.6% and 54.0%, respectively, compared with control roots. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities of R. solani AG-4-treated roots were increased by 75.1% and 23.6%, respectively. Polyphenol oxidase (PPO) activity in soybean roots challenged with P. aureofaciens 63-28 and P+R increased by 25.0% and 11.6%, respectively. Mn-SOD (S1 band on gel) and Fe-SOD (S2) were strongly induced in P+R-treated roots, whereas one CAT (C1) and one APX (A3) were strongly induced in R. solani AG-4- treated roots. The total isoflavone concentration in P+Rtreated shoots was 27.2% greater than the control treatment. The isoflavone yield of R. solani AG-4-treated shoots was 60.9% less than the control.

• 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.

• Journal of Ecology and Environment
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• v.29 no.2
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• pp.151-155
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• 2006

Root nodule biomass, and seedling biomass and growth were examined for 2-year-old Robinia pseudoacacia and Amorpha fruticosa seedlings following fertilization treatments. Organic fertilizer, solid combination fertilizer, and organic fertilizer plus solid combination fertilizer were used for the study. Root nodule biomass (g/plant) ranged from 3.00 to 7.06 for R. pseudoacacia and varied from 1.52 to 2.32 for A. fruticosa, respectively. In all treatments, root nodule biomass of R. pseudoacacia was significantly higher than those of A. fruticosa. Fertilization significantly increased root nodule biomass for only R. pseudoacacia, however, there were no significant differences in root nodule biomass among fertilization treatments. Root nodule biomass was not influenced by soil nitrogen (N) and phosphorous (P) concentrations following fertilization treatments. Seedling biomass (components and total) and growth (diameter at root collar and height) were strongly correlated with root nodule biomass for the two N fixing tree species.

• Journal of the Korean Chemical Society
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• v.65 no.2
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• pp.106-112
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• 2021

12 kinds of (-)-catechin derivatives were designed and synthesized. The catechin derivatives were evaluated their antioxidant activities using DPPH method. Most of them showed good antioxidant activity, particularly compounds 1d, 1e and 1j exhibited more activity than butylated hydroxytoluene (BHT). Molecular docking studies for compounds 1d, 1e and 1j with STAT1 showed not only sufficent characteristics binding cavity but also agreement with the observed biological activity. Acording to docking results, the compounds showed greater than hydrogen bonding, hydrophobic interactions, electrostatic interactions, and Van der Waals interactions as compared to the reference compound. They formed hydrogen bonds with important residues such as Lys566, His568, Leu570, and Phe644. The compounds showed a novel hydrogen bonding interaction with Arg649, which was not reported previously. Our results might suggest the compounds could serve as a novel anti-oxidant agent.

• Journal of Animal Science and Technology
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• v.53 no.3
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• pp.227-235
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• 2011

A total of 96 crossbred weanling barrows aged 21 days were randomly allocated to 32 pens of a new nursery to investigate the effects of antibiotics, phytogenics, and probiotics on intestinal growth and development. The animals were fed a set of three-phase basal diets containing 0.3% zinc oxide (CON) or the basal diets supplemented with 353 ppm of a combination of tiamulin, neomycin, chlortetracycline, and oxytetracycline (ANTI), 75 ppm triterpenoid saponin plus 150 ppm mixed saccharides (HERB; Sacchapin$^{(R)}$), or $1{\times}10^7$ brewer's yeasts plus $8{\times}10^7$ spores of each of Bacillus licheniformis and Bacillus subtilis per kilogram feed (PROBIO; Yeasture Plus 2B$^{(R)}$) for five weeks. Thirty-two pigs representing as many pens were slaughtered at the end of the feeding trial, after which morphological measures and digestive enzyme activities of intestinal mucosa were determined. Weight gain and gain:feed of the pigs were not affected by the dietary treatments (TRT) during the overall feeding trial. Total intestinal length was greater in PROBIO than in ANTI (P<0.05). Wet mucosa weight of the duodenum was not affected by TRT. However, jejunal mucosa weight was greater in PROBIO than in any other group sum of mucosa weights of the duodenum and jejunum was greater (P<0.05) in PROBIO than in ANTI and HERB. The height and width of duodenal villus were not affected by TRT, but crypt depth decreased (P<0.05) in response to HERB and PROBIO vs CON. Specific activities of alkaline phosphatase, sucrase, maltase, lactase, and leucine aminopeptidase in the duodenum and jejunum were not changed by TRT. In conclusion, results suggest that the present dietary treatments have no effects on growth performance of weanling pigs and that of PROBIO enhances intestinal growth and development under a clean experimental setting.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.403-410
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• 2007

A field experiment was conducted to investigate effects of application time and rate of biofertilizer alone and in combination with chemical NPK fertilizer on growth, yield and quality of rice. The biofertilizer used composted food waste as substrate and added with effective microorganism. The treatments included recommended NPK fertilizer(RF, $11-5.5-4.8kg\;10a^{-1}$), half recommended NPK fertilizer(HRF, $5.5-2.8-2.4kg\;10a^{-1}$), half recommended NPK fertilizer plus $250kg\;10a^{-1}$ biofertilizer(HRF+Bio 250) and $500kg\;10a^{-1}$ biofertilizer(HRF+Bio 500). The biofertilizer treatments were applied at 0, 5 and 10 days before transplanting(DBT). Grain yield of HRF+Bio 250 at 5 DBT($648.4kg\;10a^{-1}$) was statistically similar to the highest obtained in the RF($654.1kg\;10a^{-1}$). Tiller numbers at HRF plus biofertilizer treatments were already high during the maximum tillering stage, and were similar with that of the RF and higher than that of the HRF during heading stage. Likewise, ripening ratio at HRF plus biofertilizer treatments was similar with that of the RF and higher than that of the HRF. Furthermore, all the biofertilizer treatments improved protein content but reduced the amylose content and palatability compared to treatments with chemical NPK fertilizer alone. Thus, HRF+Bio 250 at 5 DBT can be used to save 50% chemical NPK fertilizer and at the same time obtain an improved rice grain yield and quality.

• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.251-261
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• 2017

Initially, we screened 18 Aspergillus sojae-like strains from Aspergillus spp. isolated from meju (Korean traditional fermented soybean brick) according to their morphological characteristics. Because members of Aspergillus section Flavi are often incorrectly identified because of their phylogenetic similarity, we re-identified these strains at the morphological and molecular genetic levels. Fourteen strains were finally identified as A. sojae. The isolates produced protease and ${\alpha}-amylase$ with ranges of 2.66-10.64 and 21.53-106.73 unit/g-initial dry substrate (U/g-IDS), respectively, which were equivalent to those of the koji (starter mold) strains employed to produce Japanese soy sauce. Among the isolates and Japanese koji strains, strains SMF 127 and SMF 131 had the highest leucine aminopeptidase (LAP) activities at 6.00 and 6.06 U/g-IDS, respectively. LAP plays an important role in flavor development because of the production of low-molecular-weight peptides that affect the taste and decrease bitterness. SMF 127 and SMF 131 appeared to be non-aflatoxigenic because of a termination point mutation in aflR and the lack of the polyketide synthase gene found in other A. sojae strains. In addition, SMF 127 and SMF 131 were not cyclopiazonic acid (CPA) producers because of the deletion of maoA, dmaT, and pks/nrps, which are involved in CPA biosynthesis. Therefore, A. sojae strains such as SMF 127 and SMF 131, which have high protease and LAP activities and are free of safety issues, can be considered good starters for soybean fermentations, such as in the production of the Korean fermented soybean products meju, doenjang, and ganjang.