• Journal of the Mineralogical Society of Korea
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• v.16 no.1
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• pp.33-47
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• 2003

Various applied-mineralogical characterization including measurements of surface area, size distribution, swelling index, and viscosity were done for some domestic bentonites in order to decipher the rheological properties and their controlling factors. The bentonites, which are Ca-type and relatively low-grade (rnontmorillonite contents: 30 ∼ 75 wt%), occur mostly as subhedral lamellas with the size range of 2 ∼ 4 $\mu\textrm{m}$. The size distribution of mineral fractions in bentonite suspension is dominant in the range of 10 ∼ 100 $\mu\textrm{m}$, and though rather complicated, exhibits roughly bimodal patterns. The feature is more conspicuous in the case of zeolitic bentonite. The bentonites have surface areas ranging 269 ∼ 735 $\m^2$/g, which are measured by EGME adsorption method. The EGME surface areas are nearly proportional to the rnontmorillonite contents, moisture contents, or total CEC. In the surface area measurements, zeolitic bentonites have slightly higher values than those zeolite- free types. The measured swelling index and viscosity of domestic bentonites are comparatively low in values. The swelling values of bentonites were measured to be 250∼500% at maximum by progressively mixing amounts of 2 ∼ 5 wt% Na$_2$CO$_3$, which varies depending on the contents of rnontmorillonite and other impurities, especially zeolite. Much amount of sodium carbonate is required for optimum swelling property of zeolitic bentonited which has usually strong Na- exchanged capacity. The bentonites, which are comparatively feldspar-rich and low in size and crystallinity, tend to be higher in viscosity values. Tn addition, the viscosity is largely higher in case of the bentonites with higher pH in suspension. However, the rheological properties of bentonites such as swelling index and viscosity do not show any obvious relationships with rnontmorillonite contents and mean particle size in suspension. In contrast, roughly speaking, the swelling index of bentonites is reversely proportional to the values of surface area which can be regarded as a collective physico-chemical parameter encompassing all the effects caused by mineral composition, surface charge, particle size, morphological farm, and etc. in bentonites. Thus, the rheological properties in bentonite suspension appear to be rather complicated characteristics which mainly depend on the flocculation of clay particles and the mode of particle association, i.e. quasicrystals, controlled by surface charge, morphology, size, and texture of rnon-tmorillonite, and which partly affected by the finer impurities such as zeolite.

• Geomechanics and Engineering
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• v.12 no.1
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• pp.111-125
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• 2017

Swelling and shrinkage characteristics of expansive fine grained soil cause volumetric changes followed by distress and damage to the structures. Soil stabilization can be explained as the alteration of the soil properties by chemical, mechanical or any other means in order to enhance the engineering properties of the soil. Utilization of industrial wastes in soil stabilization is cost effective and environment friendly. This paper presents an experimental study on stabilization of expansive soil using industrial wastes, viz. fly ash and dolochar. The paper includes the evaluation of engineering properties like unconfined compressive strength and California bearing ratio (CBR) of expansive soil collected from Balasore district of Odisha stabilized with fly ash and dolochar in different proportions and to predict the influence of these additives on engineering properties and strength characteristics of expansive soil. Both fly ash and dolochar were found to increase the CBR and decrease many index properties such as liquid limit, plastic limit, plasticity index, swelling index and UCS, thus enhancing the strength parameters of expansive soil.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.1
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• pp.69-77
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• 2001

PURPOSE : The Purpose of this study was to investigate the anti-inflammatory effect on combination dosage of dexamethasone and naproxen after removal of impacted 3rd molars. We evaluated postoperative pain, swelling, and mouth opening limitation quantitatively. PATIENTS AND METHODS : Removal of an impacted lower third molar was done under local anesthesia with 2% lidocaine to 239 healthy patients. We randomly gave experimental group 1.5mg dexamethasone and 200mg naproxen three times a day for postoperative 2days, and also gave control group 200mg naproxen alone three times a day for postoperative 2days. Swelling and pain were measured by visual analogue scale (VAS). Mouth opening limitation was measured by maximum interincisal opening length. We estimated these measurements in the first and second postoperative days. Differences between experimental and control group were investigated considering age, sex, BMI(body mass index), impacted type, surgical site(right or left), and operation time by independent student T-test. RESULTS : In general, swelling, pain, and mouth opening limitations were significantly reduced (p<0.01) by combination dose of dexamethasone and naproxen in postoperative one day. But there was no difference in pain on the second postoperative day. As variables being considered, in the postoperative pain, there was significant difference between experimental group and control group in only male, little bony removal group, left side extraction group. In case of postoperative swelling, there was no significant differences in male, adolescence, long operating time group (over 20 minutes), medium BMI group and right side extraction group. In case of postoperative mouth opening limitation, there was significant difference between only female and long operating time group (over 20 minutes). CONCLUSION : Variables being considered, postoperative swelling was more reduced by the combination dose of naproxen and dexamethasone than that of naproxen alone after removal of impacted 3rd molars. But there was varoius results in pain and mouth opening limitation.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.207-213
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• 2006

The effects of gellan gum (from S. paucimobilis), EPS-CB (exopolysaccharide from S. chungbukensis), and a series of commercial gums (arabic gum, xanthan gum, guar gum, deacyl gellan gum), on the swelling, rheological, and pasting properties of non-waxy rice flour dispersions were investigated. The swelling properties of rice flours in gellan or guar gum dispersion after heating were found to have increased with increasing gum concentrations, but the swelling properties of rice flour/other gum systems decreased with increasing concentrations. The rice flour/gum mixtures showed high shear-thinning flow behavior (n=0.14-0.32), and consistency index (K) was higher in guar gum than other gum dispersions. The initial pasting temperatures and peak times increased along with increasing gum concentration. The peak viscosity of rice flour increased in guar gum and deacyl gellan dispersions, and the breakdown and setback viscosity of the rice flour paste was lowest in the xanthan gum system, but remained higher than those of the control. The apparent viscosities of the rice flour/gellan gum mixture pastes were the highest among the tested combinations.

• Journal of Korean Academy of Nursing
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• v.42 no.3
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• pp.396-404
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• 2012

Purpose: The purpose of this study was to identify the features, risk scores and risk factors for deep vein thrombosis in critically ill patients who developed deep vein thrombosis in their lower extremities. Methods: The participants in this prospective descriptive study were 175 adult patients who did not receive any prophylactic medication or mechanical therapy during their admission in the intensive care unit. Results: The mean age was 62.24 (${\pm}17.28$) years. Men made up 54.9% of the participating patients. There were significant differences in age, body mass index, and leg swelling between patients who developed deep vein thrombosis and those who did not have deep vein thrombosis. The mean risk score was 6.71(${\pm}2.94$) and they had on average 4.01(${\pm}1.35$) risk factors. In the multiple logistic regression, body mass index (odds ratio=1.14) and leg swelling (odds ratio=6.05) were significant predictors of deep vein thrombosis. Conclusion: Most critically ill patients are in the potentially high risk group for deep vein thrombosis. However, patients who are elderly, obese or have leg edema should be closely assessed and more than one type of active prophylactic intervention should be provided.

• Archives of Plastic Surgery
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• v.33 no.1
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• pp.124-126
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• 2006

Pachydermodactyly is a rare distinct form of fibromatosis characterized by acquired, asymptomatic dense fibrosis and fibroblastic proliferation around one or more proximal interphalangeal joints. Intralesional triamcinolone injection may be helpful in improving the clinical appearance. A 20-year-old unemployed female patient gave a four years history of progressive swelling of the fingers affecting predominantly the proximal interphalangeal joints of index fingers of left hand and index, middle fingers of right hand. There was no pain and tenderness. Physical examination, complete blood count, antinuclear antibody, rheumatoid factor were unremarkable and radiograph of both hands showed soft tissue swelling only without bony abnormality. We excised the redundant soft tissue from the both sides of proximal interphalangeal joint with longitudinal elliptical fashion. After operation, the fingers of the patient showed marked improvement cosmetically. There were no motor or sensory changes. Pachydermodactyly was first reported in 1996 in Korea. Histologic features include an increased dermal accumulation of collagen and occasionally an increased number of fibroblast. We report for one patient with pachydermodactyly treated with longitudinal elliptical excision and obtained an improvement of clinical appearance.

• Journal of the Korean Society of Food Culture
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• v.36 no.5
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• pp.484-491
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• 2021

This study investigated the effect of dry heat treatment (DHT) on the physicochemical properties of hard type (HR) and floury type (FR) rice to improve the processing aptitude of rice flour. The rice flour was heated at 130℃ for 0, 2 and 4 hours, and the color value, water absorption index (WAI), water soluble index (WSI), swelling power, solubility, pasting properties, particle shape and the X-ray diffraction were measured. After DHT, the L value of rice flour decreased, and the b value increased. The WAI, WSI, swelling power and solubility of HR and FR increased with the increase of treatment time. The cold viscosity and setback increased, while breakdown decreased. Cracks and lumps formed with fine particles were observed. The X-ray diffraction pattern was A-type, while the diffraction intensity decreased. According to the results of the two-way analysis of variance (ANOVA) test, the hydration and pasting properties were significantly different between HR and FR and were affected by DHT time. The results suggest that the properties of modified rice flour by DHT can be used in the food industry.

• Journal of the Korean Geotechnical Society
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• v.37 no.11
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• pp.83-92
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• 2021

In this study, effective porosity measurement, electron microscope (SEM) observation, X-ray diffraction analysis (XRD), slaking, swelling, and unconfined compression strength according to water immersion were analyzed to evaluate the properties of mudstone with high porosity in Pohang. As a result of the test for 16 square samples (5 cm), the effective porosity was 14.67% on average, higher than porosity of general mudstone, and electron microscope observation confirmed that the porosity was actually high. As a result of X-ray diffraction analysis, the swelling clay mineral content was 2.3~4.1%, which was lower than the results of previous studies in Pohang. The slake durability index was 37.73~87.73%, showing low to medium durability, which was lower than the results of previous studies. It was confirmed that the swelling property rapidly expanded to 1.79~1.82% of maximum swelling strain in the major axis direction for 30 minutes. As the properties of decreasing the unconfined compression strength according to water immersion, the samples rapidly weathered after 10 minutes of water immersion, and the strength decreased. It was confirmed that the results of previous studies related to mudstone in Pohang were different. This is judged to be due to the high porosity of mudstone in study.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.71-76
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• 2007

We investigated the effects of solution pH on swelling characteristics and relevant hydraulic conductivity of different particle sizes of Na-bentonite which have significantly high swelling capacity. The results showed that the time taken to reach the maximum swelling indexes for all pH levels ranged from 84 hours and 156 hours for pH 6.5 or above by NaOH and pH 3.5 by HCl, respectively. The maximum swelling index slightly increased with increasing particle size, while the maximum swelling indexes were less or approximately half of that of the indigenous Na-bentonite. The changes in swelling indexes before and after solution treatment were distinctive in acidic condition, especially in pH 3.5 by HCl while there were not much differences in alkali condition. For hydraulic conductivities of fully swelled Na-bentonite in a given solution pH, elution did not occur under pressure below 1 bar. But elution started as the pressure was raised to 1.5 bars or above after 500 seconds. The stabilized hydraulic conductivities observed from 1.5, 3.0, and 5.0 bars ranged from $7{\times}10^{-3}cm\;day^{-1}$ to $6{\times}10^{-3}cm\;day^{-1}$, indicating that the hydraulic conductivities were slightly higher in acidic condition than that of normal condition.

• Journal of the Korea Convergence Society
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• v.12 no.3
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• pp.317-323
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• 2021

The purpose of this study was to analyze the oral symptoms experienced by adolescents according to Body Mass Index. We analyzed the data using the Korea Youth Risk Behavior Web-based Survey and conducted complex-sample descriptive statistics on 55,728 participants. The prevalence of sensitive teeth, tooth pain, gingival bleeding, and swelling was highest in the overweight group (36.8%, 23.9%, and 19.2%) and lowest in the underweight group (34.6%, 20.8%, and 17.0%) (p<0.001). Tooth pain, gingival bleeding, and swelling were significantly higher (all 1.08) in the overweight group than in the normal group. Halitosis was 1.19-and 1.43-higher in the overweight and obese groups, respectively. The relationship between systemic diseases and oral health among adolescents should be further investigated.