• Korean Journal of Dental Materials
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• v.44 no.4
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• pp.311-318
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• 2017

The purpose of this study was to examine the effects of the curing sequence and polymerization temperature on the flexural strength and microhardness of two provisional resins (Bis-acryl resin composite and polymethyl methacrylate (PMMA)). Polymerization was carried out under various conditions, in air at $25^{\circ}C$ (control) and in hot water (40, 50, 60, 70, and $80^{\circ}C$). The flexural strength test was conducted according to ISO-4049. The Knoop hardness was measured. For the Bis-acryl resin, the temperature up to $50^{\circ}C$ did not increase the flexural strength nor the hardness of the bis-acryl resin composite (p>0.05) but higher temperatures increased the strengths. For the PMMA resin, flexural strength increased with temperatures up to $70^{\circ}C$ and then decreased slightly. Bis-acryl resin composite had higher mechanical properties than the PMMA resin. The effect of heat was more pronounced in the bis-acryl resin composite than in the PMMA resin (p<0.05).

• Journal of agriculture & life science
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• v.45 no.6
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• pp.151-162
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• 2011

Methanol and hexane extracts from 35 species in 27 families of herbal plants were evaluated for their acaricidal activities against two-spotted spider mite, Tetranychus urticae by leaf-dipping and spraying methods in laboratory, pot and field, respectively. Acaricidal activities were different depending on herbal plants. When T. urticae was released on leaves of Phaseolus vulgaris var. humilis that were dipped in the 1,000 ppm hexane extracts from fruits of Torreya nucifer and Daphan genkwa, seeds of Xanthium strumarium and Pharbitis nil at one minute they experienced 56.8, 47.8, 47.7, and 47.7% mortalities, respectively. Dipping time influenced acaricidal activity, that is, one minute dipping was more effective than 30 second dipping of Phaseolus vulgaris var. humilis leaves. However, extracts of X. strumarium and P. nil seeds had comparatively high activities. Concentration of hexane extract of X. strumarium and P. nil seeds revealing LC50 were 1,824 and 1,899 ppm, respectively. Extracts of both plants from hot and cold water were not effective representing <20% mortality at 1,000 ppm. However, hexane extracts of X. strumarium and P. nil seeds were effective against T. urticae on P. vulgaris var. humilis representing 76.3 and 71.3% mortalities in pot, respectively. Control effects of hexane extract of P. nil seed were 50.8 and 35.1% at 2,000 and 1,000 ppm against T. urticae on Chrysanthemum morifolium in greenhouse, respectively.

• FLOWER RESEARCH JOURNAL
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• v.19 no.3
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• pp.151-157
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• 2011

This research was aimed to extend the vase life and improve the quality of cut roses 'Marina'. This study investigated the effect of three different angles and sucrose concentration on the vase life and the quality of cut rose flowers. In first experiment, cut roses were placed in three different angles ($0^{\circ}$, $45^{\circ}$ and $90^{\circ}$) in holding solutions containing 0.5, 1 and 2% sucrose (soaking treatment), and examined the number of petals of cut roses. In second experiment, cut roses were placed in three different angles after pre-treated in 0, 1, 2 and 4% sucrose solution for 2 and 20 hours, and examined the flower diameter of cut roses. In third experiment, cut roses were examined the pigmentation, flowing response and chlorophyll contents in cut roses by three different angles after pulsing treatment (pre-treatment) in holding solution containing 2% sucrose for 2 and 20 hours. Results of this study showed that cut roses were influenced by arranging angles and sucrose concentrations. The vase life of cut roses were extended in $45^{\circ}$ and $90^{\circ}$ arranging angle, as compared with the control (distilled water), and the holding solution containing 2% sucrose significantly increased vase life of cut roses(P < 0.05). Flower diameter of cut roses pre-treated in 4% sucrose solution for 2 and 20 hours significantly decreased (P < 0.05). The pigmentation and flowing response in cut roses were beneficial in $45^{\circ}$ arranging angle treated with 2% sucrose solution for 2 and 20 hours. Chlorophyll content in leaves of cut roses was not influenced by arranging angles. The pigmentation and flowing response of $0^{\circ}$ and $45^{\circ}$ arranging angles were better than that of 90 arranging angle. The vase life of cut roses in $45^{\circ}$ arranging angle was more prolonged than that in $90^{\circ}$ arranging angle. In conclusion, the arranging angles seem to be effective in retarding senescence of cut rose flowers.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.125-134
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• 2011

This study was carried out to investigate the effects of Opuntia ficus-indica var. saboten (OFIS) powder addition replacing nitrite on quality characteristics of sausages stored at $4^{\circ}C$ during 15 days. All samples were divided into six different treatments as follow: C (non-sodium nitrite and -O. ficus-indica var. saboten powder), T1 (0.014% sodium nitrite), T2 (0.014% sodium nitrite + 0.5% O. ficus-indica var. saboten powder), T3 (0.014% sodium nitrite + 1.0% Opuntia ficus-indica var. saboten powder), T4 (0.5% O. ficus-indica var. saboten powder) and T5 (1.0% O. ficus-indica var. saboten powder), respectively. The lightness (CIE $L^*$) of negative control (C) was higher than other treatments (p<0.05), and the redness (CIE $a^*$) of T5 treatment showed an intermediate value between T1 and T3 treatment. Yellowness (CIE $b^*$), water holding capacity (WHC) and cohesiveness, springiness and chewiness of T5 treatment were higher than other treatments (p<0.05). However moisture content, pH and whiteness of T1 treatment were the highest (p<0.05). No differences in sensory evaluation were observed between T1 and T5 treatment (p>0.05). Therefore, the results indicate that OFIS powder improves color and texture properties of sausage, however, specific study related to self-life due to the addition of OFIS powder to sausages may be conducted.

• Journal of agriculture & life science
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• v.43 no.6
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• pp.95-103
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• 2009

To develop natural intermediate flavoring substances, optimal hydrolysis conditions and taste compounds for two step enzyme hydrolysate(TSEH) using Grass puffer(Takifugu niphobles) were investigated. The optimal conditions for TSEH method were revealed in temperature at $55^{\circ}C$ 3 hour digestion with Alcalase (pH 7.5) at the 1st step and 2 hour at $45^{\circ}C$ digestion with Flavourzyme(pH 6.0~6.5) at the 2nd step. TSEH method was superior to hot-water extraction on the aspect of yield, nitrogen contents and organoleptic taste quality such as umami and control of bitter taste formation. In taste active-components in Glass puffer TSEH, total free amino acid content was 4,502 mg%, major free amino acids were Pro, Leu, Lys, Hypro, Tau, Arg, Phe, Ala, Glu and Val in ordor. As for nucleotides, IMP(372 mg%) was the principal component and also contents of TMAO, total creatinine, and betaine were 43, 278 and 41 mg% in Glass puffer TSEH, respectively. The major inorganic ions in TSEH were Na(949 mg%), K(222 mg%), Cl(1,180 mg%) and $PO_4$(1,081 mg%).

• Journal of agriculture & life science
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• v.44 no.1
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• pp.25-32
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• 2010

This study examined the effect of moisture level at ensiling on fermentation characteristics of barley and rye silage. The moisture levels, 60 (low; LM), 70(medium; MM) and 80% (high; HM), were controled by adding water or pre-wilting. Barley silage had higher pH and latate:acetate ratio in LM than the other treatments, but those of rye in MM were higher. The concentrations of lactate, total FA and acetate in HM were higher than the other treatments, but propionate concentration in LM was higher than HM. Total N concentrations of barley and rye were highest in MM and LM, respectively. The $NH_3-N$ concentration and total N:$NH_3-N$ ratio of barley were higher in HM than those in LM and MM. With increasing moisture content, buffering capacity of barley and rye silages increased, whereas decreased by increase of pH. There was a negative correlation between moisture content vs. pH of barley and rye silages. However, moisture content vs. the concentrations of total VFA and $NH_3-N$ and the ratio of total N:$NH_3-N$ had a positive correlation. Tn conclusion, the ideal moisture content of barley and rye for silage was 70-80%, but silage quality could be rapidly decreased by pre-wilting to 60% moisture content.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.51-69
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• 2012

Physical strength of the rock is the most important factor of resistance to erosion and has been measured through various way. Bedrock microforms, like potholes and grooves, are the forms sculpted by the erosional processes of flow and the location and morphology are strongly affected by the differential erosion. It also assumed that the physical strength of the rock controls the erosion rate and mode of erosion. The schmidt hammer has been used to measure the rock strength in the field for the geomorphological research. To find the relationship between the rock strength and microforms, Schmidt hammer's R(rebound) were measured in the Baeksuktan, middle reach of Gilancheon, Cheongsong, Gyungsangbuk do. The overall values of rebound of the local sandstone showed over 65 in most cases, so it can be regarded as 'very strong'. It is found that the rebound values of the rock surface decreased towards current water level. It also, however, found that there was no systematic differences in rebound values among the topographically high and lows in the bedrock surface. There was no statistically significant difference in rebound values of the area with well developed microforms and others. The values of R from the exposed faces and inside of the microforms are similar. In the case of conglomerate, the part with the gravel showed higher values that the parts with sands. The rebound values are decreased near of(<1cm) the geological discontinuities(including joint and faults), so this line of weakness could be the point of initiation of active erosion to form microforms. However there is large variations in rebound values within this part. It also should be mentioned that topological relation between the strike of the geologic discontinuities and flow direction looks control the mode of erosional processes.

• Journal of Korean Medicine Rehabilitation
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• v.29 no.4
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• pp.29-45
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• 2019

Objectives This study is to investigate anti-obesity effects of Banggihwanggi-tang-hap-yeonggyechulgam-tang (BY), an herbal formula, in high fat diet induced obese mice model. Methods Fourty five male C57Bl/6J mice were randomly assigned to normal group fed with normal research diet (Nor, n=9), high fat diet control group treated with water (Veh, n=9), high fat diet group treated with orlistat (Oris; n=9, Orlistat 40 mg/kg), high fat diet group treated with low concentraion BY (BYL; n=6, BY 0.87 g/kg) and high fat diet group treated with high concentration BY (BYH; n=6, BY 1.74 g/kg). Results Seven weeks later, antioxidative capacity, body weight, epididymal fat pad and liver weight, reactive oxygen species (ROS), peroxynitrite ($ONOO^-$), alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol, triglyceride, high density lipoprotein (HDL), low density lipoprotein (LDL), superoxide dismutase (SOD), catalase, glutathione peroxidase (Gpx), heme oxygenase (HO)-1 and histology of liver were evaluated. In the BYH group, 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis (3 ethybenzothiazoline-6-sulfonic acid) radical scavenging activity were more than L-ascorbic acid. Body weight gain were significantly less than Veh group. Epididymal fat pad and liver weight gain were significantly less than Veh group. ROS and $ONOO^-$ were significantly less than with Veh group. ALT and AST were significantly less than with Veh group. Total cholesterol, triglyceride and LDL were significantly less, HDL were significantly more than Veh group. SOD, catalase, Gpx, HO-1 significantly increased compared with Veh group. Injury on liver was lesser than Veh group. Conclusions It can be suggested that BY has anti-obesity effects in high fat diet induced obese mice model.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1873-1881
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• 2019

Objective: Information regarding the vitamin content of silage is limited. This study investigated the changes in the vitamin content of alfalfa and Chinese leymus silages with or without a lactic acid bacterial inoculant. Methods: Alfalfa at the early flowering stage and Chinese leymus at the full-bloom stage were harvested. The treatments for each forage type were control (deionized water only) and $1{\times}10^6$ colony-forming units Lactobacillus plantarum (LP)/g fresh matter. After 45 days of ensiling, all silages were sampled for evaluating the vitamin content, fermentation quality and chemical composition. Results: The LP inoculant decreased the pH value and ammonia nitrogen content of the alfalfa and Chinese leymus silages and significantly (p<0.05) increased the lactic acid, acetic acid concentrations and Flieg's points. Prior to ensiling, the levels of five B-group vitamins (thiamin, riboflavin, niacin, pantothenic acid, and pyridoxine) and ${\alpha}$-tocopherol in alfalfa were significantly (p<0.01) higher than those in Chinese leymus. Ensiling decreased the levels of the five B-group vitamins in both alfalfa and Chinese leymus while increasing the ${\alpha}$-tocopherol content of Chinese leymus. The thiamin, riboflavin, niacin and pantothenic acid levels in the LP-treated silage were significantly (p<0.05) lower than those in the untreated silage for the alfalfa and Chinese leymus. The ${\alpha}$-tocopherol content in the LP-treated alfalfa silage was significantly (p<0.05) higher than that in the untreated alfalfa silage. There was no significant (p>0.05) difference in pyridoxine content between the untreated and LP-treated silages for both forages. Conclusion: With or without LP inoculation, the levels of the five B-group vitamins (thiamin, riboflavin, niacin, pantothenic acid, and pyridoxine) in alfalfa and Chinese leymus decreased after 45 days of ensiling, while the ${\alpha}$-tocopherol content of Chinese leymus increased. The LP inoculant improved the fermentation quality of both the alfalfa and Chinese leymus silages but increased the thiamin, riboflavin, niacin, and pantothenic acid loss in the two forages after fermentation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.4
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• pp.459-466
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• 2018

Hazardous and Noxious Substances (HNS) are defined as substances that are likely to create a significant impact on human health and marine ecosystem when they are released into the marine environment. Recently, as the volume of HNS transported by ships increases, the rate of leakage accidents also increases. Therefore, research should be conducted to control and monitor sunken materials from the viewpoint of technology development for hazardous material leakage accident response. In this paper, acoustic detection experiments were carried out using HNS substitute materials in order to confirm the possibility of acoustic detection of sunken HNS on the sediment. The castor oil, which has a similar acoustic impedance with chloroform, is used as a substitute. 200 kHz high frequency signals were used to discriminate the reflected signals and measure reflection loss from the interface between water and castor oil. The reflection loss measured is in good agreement with the modeling results, showing a possibility of acoustic detection for sunken HNS.