• Restorative Dentistry and Endodontics
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• v.32 no.2
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• pp.111-120
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• 2007

The purpose of this study is to evaluate the effects of surface treatment and composition of reinforcement material on fracture strength of fiber reinforced composite inlay bridges. The materials used for this study were I-beam, U-beam TESCERA ATL system and ONE STEP(Bisco, IL, USA). Two kinds of surface treatments were used; the silane and the sandblast. The specimens were divided into 11 groups through the composition of reinforcing materials and the surface treatments. On the dentiform, supposing the missing of Maxillary second pre-molar and indirect composite inlay bridge cavities on adjacent first pre-molar disto-occlusal cavity, first molar mesio-occlusal cavity was prepared with conventional high-speed inlay bur. The reinforcing materials were placed on the proximal box space and build up the composite inlay bridge consequently. After the curing, specimen was set on the testing die with ZPC. Flexural force was applied with universal testing machine (EZ-tester; Shimadzu, Japan). at a cross-head speed of 1 mm/min until initial crack occurred. The data was analyzed using one-way ANOVA/Scheffes post-hoc test at 95% significance level. Groups using I-beam showed the highest fracture strengths (p<0.05) and there were no significant differences between each surface treatment (p>0.05) Most of the specimens in groups that used reinforcing material showed delamination. 1. The use of I-beam represented highest fracture strengths (p<0.05) 2. In groups only using silane as a surface treatment showed highest fracture strength, but there were no significant differences between other surface treatments (p>0.05). 3. The reinforcing materials affect the fracture strength and pattern of composites inlay bridge. 4 The holes at the U-beam did not increase the fracture strength of composites inlay bridge.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.3
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• pp.328-334
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• 2009

Statement of problem: Pier abutments act as a Class I fulcrum lever system when the teeth are incorporated in a fixed partial denture with rigid connectors. Therefore non-rigid connector incorporated into the fixed partial denture might reduce the stresses created by the leverage. Purpose: The purpose of this study was to evaluate, by means of finite element method, the effects of non-rigid connectors and supporting alveolar bone level on stress distribution for fixed partial dentures with pier abutments. Material and methods: A 2-dimensional finite element model simulating a 5-unit metal ceramic fixed partial denture with a pier abutment with rigid or non-rigid designs, the connector was located at the distal region of the second premolar, was developed. In the model, the lower canine, second premolar, and second molar served as abutments. Four types of alveolar bone condition were employed. One was normal bone condition and others were supporting bone reduced 20% height at one abutment. Two different loading conditions, each 150 N on 1st premolar and 1st molar and 300N on 1st molar, were used. Results: Two types of FPD were displaced apically. The amount of displacement decreased in an almost linear slope away from the loaded point. Non-rigid design tended to cause the higher stresses in supporting bone of premolar and molar abutments and the lower stresses in that of canine than rigid design. Alveolar bone loss increased the stresses in supporting bone of corresponding abutment. Conclusion: Careful evaluation of the retentive capacity of retainers and the periodontal condition of abutments may be required for the prosthetic design of fixed partial denture with a pier abutment.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.295-303
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• 2007

A preliminary diet experiment utilizing Jerusalem artichoke's inulin, lotus leaf powder, nettle powder and eucalyptus powder extract indicated that combining all four elements gave the most effective result. Therefore, a study was conducted to evaluate the effectiveness of combined diet for weight loss. In this study, Sprague-Dawley, male white rats about 200 g in weight was fed with high fat diet for 8 weeks in order to induce obesity followed by 4 week administration of combined diet to look into the effect of the diet. After a total of 12 weeks of feeding, factors relevant to weight, blood, and lipid metabolism by liver in the body were researched and histologic change was examined with optical microscope. In terms of weight change, both high fat diet group and regular diet group gained weight from high fat diet for 8 weeks compared to normal group. Then, for another 4 weeks, while normal group and high fat diet group kept gaining weight, combined diet group which was provided with high fat diet for 8 weeks, lost weight to the normal group level after 3 week administration of diet. However, after the 4th week of administration, the group weighted significantly less than the normal group and the efficiency of diet also significantly dropped. In the biochemical analysis of blood, total cholesterol, LDL-cholesterol, triglyceride, glucose, GOT, GPT, ${\gamma}-GTP$ and creatine showed significant increase in high fat diet group and there was no significant difference between diet group and normal group except for GPT, ${\gamma}-GTP$ and creatine. In the biochemical analysis of liver, there was significant increase in LDL-cholesterol, triglyceride of high fat diet group compared to normal group, while there was no significant difference in term of total cholesterol and HDL-cholesterol. Compared to normal group, diet group had higher HDL-cholesterol, while total cholesterol dropped significantly. There was no significant difference in terms of LDL-cholesterol and triglyceride. Besides, in high fat diet group, observation of histologic change in liver and change in ultrastructure showed volume increase of hepatic cell and severe fatty degeneration in hepatic cell around hepatic vein. However in diet group, like normal group, no pathological change was observed in terms of cytoplasm, nucleus and capillary in hepatocyte and the alignment of hepatocyte had regularity thanks to the administration of combined diet. Therefore, combined diet utilizing Jerusalem artichoke's inulin, lotus leaf powder, nettle powder and eucalyptus powder was proven to be an effective measure to prevent and improve obesity as a result of abnormal adipose deposition.

• Korean Journal of Psychosomatic Medicine
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• v.25 no.2
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• pp.200-209
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• 2017

Objectives : The aim of this study was to analyze the relationship between depressive symptoms and sociodemographic factors associated with geriatric depression and insomnia and to examine the effects of these factors on depression. Methods : The severities of insomnia and depression in elderly aged 60 and older lived in Gwangmyeong city were evaluated and the related sociodemographic factors were investigated. From April 20, 2016 to December 1, 2016, Gwangmyeong city Mental Health Sevices consignment by department of psychiatry of a university-affiliated general hospital conducted surveys and interviews for total 837 elderly peoples lived in Gwangmyeong city by visiting welfare center and wards located in the city. Structured interviews were conducted using Insomnia Severity Index(ISI) and Short form-Geriatric Depression Scale(S-GDS) to examine the relationship between sociodemographic factors and the severities of insomnia and depression. Results : There were significant differences in S-GDS mean scores and age(below 70 years old, 70s, 80s, above 90 years old), type of health care(health insurance, medical aid), type of residency(own, not own) and marital status(single, married, divorced or widowed).There was a significant difference in education level, especially between not educated(and/or) elementary graduates and college graduate(F=3.227, p=0.012). Also, there were significant differences in age, type of health care, type of residency, number of household on divided S-GDS score above and below 10 scores(p<0.05). Insomnia measured by ISI was not significantly associated with sociodemographic factors(p>0.05), but was significantly associated with depressive symptoms(p<0.05). These findings suggest more severe insomnia symptom indicated the higher probability of depression and elderly with depressive symptoms had more severe insomnia. Conclusions : Geriatric depression has significant relationships with age, type of health care, type of residency, marital status, education and number of households. In addition, insomnia which is main symptom of depression in elderly, has important role in predicting the severity and diagnosis of depression.

• Journal of Oral Medicine and Pain
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• v.38 no.1
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• pp.35-51
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• 2013

The aims of this study was to observed an effect of antioxidative in cardiac muscle of high fat diet induced obesity rat by treadmill exercise with intensity and time. Thirty-two Sprauge-Dawley rats which were divided into four group. Normal, Control(high fat diet induced obesity rat), Experimental I(high intensity intermittent exercise in high fat diet induced obesity rat), Experimental II(moderate intensity endurance exercise in high fat diet induced obesity rat). The results of this study were as follows: 1. In change of body weight, the outcome of each group significantly difference compared with control. Also, 1 to 3 weeks significantly different compared with pre valu experimental I and II(p<0.001). 2. In change of lipid profile, the outcome of each group significantly difference compared with control(p<0.001). Difference between experimental I and II is not significantly. 3. In change of antioxidative enzymes(SOD, CAT, GPx) in myocardium, there are significant difference between control and experimental II, and also between control and experimental I(p<0.001). 4. In change of antioxidative protein MCR-1, the outcome of each group significantly difference compared with control(p<0.01). Experimental II was most significantly difference than the other group(p<0.001). The above results suggest that treadmill exercise effectively reduced in fat. It would be considered that moderate intensity endurance exercise has an effects on improved antioxidative enzyme in cardiac muscle of high fat diet induced obesity rat.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.313-319
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• 2006

Two hundred bacterial strains were isolated from the soil around healthy tomato plants in a polyvinyl house, where most of the other plants showed bacterial wilt symptoms. The strains were screened in vitro for their antibacterial activity. Among them, a strain, KPB3 showed strong bactericidal activity against bacterial wilt pathogen, Ralstonia solanacearum. The strain KPB3 was identified using physiological and biochemical tests, and 16S rRNA analyses. Based on these tests, the strain was found to be closer to genus Paenibacillus. To control the bacterial wilt caused by R. solanacearum, greenhouse experiments were conducted to determine the effectiveness of the Paenibacillus strain KPB3. Drench application of this strain ($4{\times}10^8$ CFU $mL^{-1}$) into the pots containing tomato plants, post-inoculated with the pathogen, R. solanacearum could drastically reduce the disease severity, compared to the non-treated plants. To evaluate effectiveness of this strain under field conditions, experiments were carried out in polyvinyl houses infested with R. solanacearum, during spring and autumn of the year 2006. It was observed that, during spring, bacterial wilt was more prevalent compared to the autumn. During spring, 50.9% disease incidences occurred in non-treated controls, while, Paenibacillus strain KPB3 treated plants showed 24.6% disease incidences. Similarly, during autumn, around 17.2% plants were infected with bacterial wilt in non- treated polyvinyl houses, compared to the Paenibacillus strain KPB3 treated plants, which showed 7.0% disease incidences. These results demonstrated that, Paenibacillus strain KPB3 is a potential biological control agent against bacterial wilt caused by R. solanacearum, effective under greenhouse as well as field conditions. This is the first report showing biocontrol of R. solanacearum using a Paenibacillus spp. under field conditions.

• Progress in Medical Physics
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• v.19 no.3
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• pp.191-199
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• 2008

PTV considered for the energy, dose distribution exposed to lung and spinal cord, and the characteristic of DVH(Dose Volume Histogram) were compared and investigated by planning the intensity modulated radiation therapy (IMRT) using the photon energies of 6 MV and 10 MV according to tumor location like as the anterior, middle, and posterior regions of lung, and the mediastinum region in lung cancer patients. Our institution installed the linear accelerator (Varian 21 EX-s, USA) equipped with 120 multileaf collimator for lung cancer patients, which is producing the photon energies of 6 MV and 10 MV, and radiation therapy planning was performed with ECLIPSE system (Varian, SomaVision 6.5, USA), which support inverse treatment planning. The tomographic images of 3 mm slice thickness for lung cancer patients were acquired using planning CT, and acquired tomographic images were sent to the Varis system, and then treatment planning was performed in the ECLIPSE system. The radiation treatment planning of the IMRT was processed from various angles according to the regions of the tumor, and using various beam lines according to the size and location of the tumor. The investigation of the characteristic of dose distributions for the energy of 6 MV and 10 MV according to tumor locations in lung cancer patients resulted that the maximum dose of 10 MV energy was 1.2% less than that of 6 MV energy without depending on the tumor location of lung cancer, and the reduction effects of MU were occurred from 10 to 25 MU. Radiation dose exposed to the lung satisfied the less 30% of V20, however radiation dose in 6 MV energy was from 0.1% to 0.5% less than that in 10 MV energy. Radiation dose exposed to the spinal cord for 6 MV energy was from 0.6% to 2.1% less than that for 6 MV energy.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.208-216
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• 2011

The purpose of this study was to find soil-amendment materials those support the growth of Kentucky bluegrass and reduce salt accumulation at the sand based growing media in saline conditions. Rootzone profile in columns consisted of 20 cm of top soil, 20 cm coarse sand as capillary rise interruption layer and 10 cm reclaimed paddy soil as the base of the profile. Top soils were mixtures of dredged sand (DS) and amendment with compositions of 90% sand + 10% peat moss (SP), 80% sand + 10% soil + 10% bottom ash (SSoBa), 80% sand + 20% soil (SSo), 90% sand + 5% peat + 5% zeolite (SPZ), and 80% sand + 20% bottom ash (SBa). The top soil mixtures of DS and amendments were treated with and without gypsum (Gp). The columns were soaked into 5 cm depth saline water reservoir with the salinity level of $3-5dSm^{-1}$. Irrigation of $2dSm^{-1}$ saline water with rate of $5.7mm\;day^{-1}$ was applied by 3 day interval. Application of zeolite decreased SAR, application of gypsum decreased ECe of the sand amended by peat + zeolite and decreased the SAR of sand amended by bottom ash. The SP and SSoGp resulted in higher clipping dry weight of Kentucky bluegrass. The SSoGp and SPZGp showed longer root lengths. The SP and SBaGp showed higher visual quality. Addition of gypsum to soil and bottom ash treatments resulted in the increased shoot growth, whereas additional gypsum to the treatments of peat, soil and zeolite increased the root growth of Kentucky bluegrass.

• Proceedings of the Turfgrass Society of Korea Conference
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• 2011.02a
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• pp.5-8
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• 2011

This research was conducted to determine the effect of capillary rise interruption layer on the sand based growing media when growing Kentucky bluegrass under soil reclamation and saline water irrigation. Rootzone profile consists of three layers as top soil of 30 cm, 20 cm of capillary interruption layer and 10 cm of reclaimed paddy soil. Rootzone profile was packed in column pots. The top soil was a mixture of sand dredged up from Lake Bhunam Tae Ahn, Korea and peat at the ratio of 95:5 by volume. Bottom part of column was covered with plastic net and the pots were soaked into 5 cm depth saline water reservoir with salinity $3-5dsm^{-1}$. Kentucky bluegrass was installed by sod and irrigated using $2dSm^{-1}$ saline water(5.7mm $day^{-1}$)in 3days interval. The results showed that the largest accumulation of salt in the spring with ECe of $5.4dSm^{-1}$ and SAR34.0 in rootzone with out capillary rise interruption layer and ECe of $4.6dSm^{-1}$ and SAR8.24 at rootzone using gravel as capillary rise interruption layer material. Kentucky bluegrass grown in growing media with gravel as capillary rise interruption layer resulted in the average visual quality rate of 8.1and clipping dry weight of $24.8gm^{-2}$, while Kentucky bluegrass grown in the growing media with out capillary rise interruption layer showed the visual quality rate of 7.9 and clipping dry weight of $34g.m^{-2}$. Capillary rise interruption layer of gravel and coarses and enhanced the visual quality by 4.1and 4.0%, root length by 50 and 38%, and root dryweight by 35and 17% of Kentucky bluegrass, and reduced the accumulation of Na by 16% and 25%, ECe by 7% and 13% in the rootzone.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.61-71
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• 2000

When irradiate the power ultrasound into the aqueous solutions, water vapor is decomposed by the heat of very high temperature in the cavitation bubble to produce OH (hydroxyl radical) and H (hydrogen radical), and these radicals play a role in decomposing the substances in aqueous solution by oxidation and/or reduction, and in producing the hydrogen peroxide. Accordingly it is possible to predict that the quantity of hydrogen peroxide produced may correlate with the sonolysis mechanism of the substance in aqueous solution. Thus to confirm this prediction, the quantities of hydrogen peroxide produced from each of the air saturated distilled water and three aqueous solutions of TCE, benzene, and 2,4-DCP that are prepared by dissolving them into distilled water are measured. As a result, it showed that the quantity of hydrogen peroxide produced from the distilled water and three aqueous solutions are increased in order of distilled water>TCE solution>2,4-DCP solution>benzene solution, and decrease with decrease in concentration of organic substance, which coincide with the sonolysis mechanisms reported that TCE in aqueous solution is decomposed directly by the pyrolysis in and around the cavitation bubbles when its concentration is high and by the radical reaction when low, however, benzene and 2,4-DCP are decomposed not only by the pyrolysis but also by the radical reactions. Effects of such experimental parameters as the acoustic frequency and power and as the concentration showed that the higher the acoustic frequency and the lower the acoustic power, the less the quantity of hydrogen peroxide was produced. This result coincide with the theory of ultrasound for the relation between the cavitation that is the energy source of the power ultrasound in aqueous solution and these experimental parameters.