• Journal of Food Hygiene and Safety
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• v.16 no.2
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• pp.111-116
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• 2001

This study was carried out to evaluate the irritant potential of P-toothpaste in hamster cheek pouch. The test materials were applied once at the beginning of this study into right pouches of hamsters and maintained for 14 days. Animals were administered with P-toothpaste, Bamboo salt toothpaste, D.W. and control solution, respectively. In order to evaluate the irritant potential in mucosa of hamster cheek pouch, we observed clinical signs, morality, body weights and gross and histopathological findings for 14 days. In all groups, there were neither dead animals nor significant changes of body weights. In addition, there were no differences between D.W. and P-toothpaste treated group in gross and histopathological findings. Therefore, these results suggest that there was little irritant potential of P-toothpaste in hamster cheek pouch.

• Journal of Biomedical Engineering Research
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• v.19 no.5
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• pp.539-546
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• 1998

The purpose of this study is to estimate human emotion quantitatively under colors and music stimuli and to examine the for correlation between color and music sensibility. Physiological signals(electroencephalogram, electrocardiogram, Galvanic skin conductivity and respiration rate) were measured to compare color with music sensibilities. The personality of the subject were investigated using factor analysis and semantic differential method of 20 items(7 interval scaled). The results showed that red, yellow and violets color provoked active and exciting senses mainly as dance, rock and blues music. While blue, cyan and pink colors ware involved in tranquil and resting emotions deeply as classic and ballade music.

• The Journal of the Korea Contents Association
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• v.16 no.4
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• pp.275-288
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• 2016

A decision tree analysis was performed by categorizing the idea sketches produced in the group environment into three different levels of visual stimuli ambiguity (vague, ambiguous, and definite) and two idea-sharing situations (before and after). We then examined the predicted values for the creativity of each group's idea sketches, the factors that led to high creativity scores, and their standards. The results of the analyses indicated that the Resistance to Premature Closure, Originality, Elaboration, ness, and Similarity represented important predictors of the creativity of design idea sketches according to the level of ambiguity of the visual stimuli used and whether ideas were shared or not. The group presented with vague stimuli after sharing ideas scored the highest predicted creativity value and the group presented with definite stimuli after sharing ideas scored the lowest predicted creativity value.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.2
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• pp.481-486
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• 2018

In this paper, we aimed to analysis EEG signals related to the relativity between musical stimuli and human brain activity for the arithmetical calculation and present the experimental results. We use two kinds of musical stimuli, one is a sedative tendency music and the other is a stimulative tendency music. The SMR wave and Mid-beta wave are analyzed because of the concentration. In our results, the sedative tendency music is not more interfere with human brain activity for the arithmetical calculations than the stimulative tendency music.

• Korean Journal of Cognitive Science
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• v.12 no.4
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• pp.41-47
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• 2001

Palmer and Rock (1994) proposed that a connected region of uniform visual properties (uniform connectedness) strongly tends to be organized as a single perceptual unit To test this hypothesis using briefly presented forms three experiments were executed. In Experiment 1 and 2 participants were asked to report the identity of a post-cued target. and there was no difference between connected and disconnected displays. In Experiment 3 participants were asked to report the predesignated name of each whole display and the accuracy rate was higher in the connected displays than in the disconnected ones. However negative repetition effects were observed consistently in all the experiments. This indicates uniform connectedness does not have a strong effect in perceiving briefly presented forms.

• Science of Emotion and Sensibility
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• v.13 no.3
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• pp.541-550
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• 2010

The present study examined whether the physical similarity of test stimuli affects P300 amplitude and detection accuracy for the P300-based concealed information test (P300 CIT). As the participant pretended suffering from memory impairment by an accident, own name was used as a concealed information to be probed by the P300 CIT in which the participant discriminated between a target and other (probe, irrelevant) stimuli. One group of participants was tested in the easy task condition with low physical similarity among stimuli, the other group was tested in the difficult task condition with high physical similarity among stimuli. Using the base-to-peak P300 amplitude, the interaction effect of task difficulty and stimulus type was significant at $\alpha$=.1 level (p=.052). In the easy task condition the difference of P300 amplitude between the probe and the irrelevant stimuli was significant, while in the difficult task condition the difference was not significant. Using peak-to-peak P300 amplitude, on the other hand, the interaction effect of task difficulty and stimulus type was not significant with significant differences of P300 amplitude between the probe and the irrelevant stimuli in both task difficulty conditions. The difference of detection accuracy between task conditions was not significant with both measures of P300 amplitude although the difference was much smaller when peak-to-peak P300 amplitude was used. The results suggest that the efficiency of P300 CIT would not decrease even when the perceptual similarity among test stimuli is high.

• Journal of dental hygiene science
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• v.5 no.3
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• pp.97-103
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• 2005

Irritation fibroma (IF) is the most common tumor-like oral lesion that is evolved by proliferation of collagen in response to chronic irritation. Oral leukoplakia (OL) is considered as precancerous lesion characterized by proliferation of epithelial cells due to chronic irritation, smoking and drinking. TGF-${\beta}1$ and EGFR are important factors that play an essential role in extracellular matrix remodeling during normal wound healing process. The epithelial reaction by chronic irritation may be connected with pathogenesis of IF and OL. In the present study, we examined the expression of TGF-${\beta}1$ and EGFR in the IF and OL using immunohistochemistry. We used 88 cases of IF, 44 cases of OL and 9 cases of normal oral mucosa as normal control. TGF-${\beta}1$ was decreased in the epithelium of IF and OL. As for EGFR, the epithelial cells revealed the increased positive expression in IF and OL. In case of OL, the Spearman correlation coefficient of TGF-${\beta}1$ and EGFR was -0.10 (p< 0.05), which showed weak correlation. In the fibrous tissue, TGF-${\beta}1$ was increased only in IF. The expression difference of TGF-${\beta}1$ and EGFR may be involved in the pathogenesis of IF and OL.

• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.365-373
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• 2007

Destruction of oral soft and hard tissues and resulting problems seriously affect the life quality of xerostomic patients. Although artificial saliva is the only regimen for xerostomic patients with totally abolished salivary glands, currently available artificial salivas give restricted satisfaction to patients. The purpose of this study was to contribute to the development of ideal artificial saliva through comparing viscosity and wettability between CMC solutions and human saliva. Commercially-available CMC is dissolved in simulated salivary buffer (SSB) and distilled deionized water (DDW). Various properties of human whole saliva, human glandular saliva, and a CMC-based saliva substitutes known as Salivart and Moi-Stir were compared with those of CMC solutions. Viscosity was measured with a cone-and-plate digital viscometer at six different shear rates, while wettability on acrylic resin and Co-Cr alloy was determined by the contact angle. The obtained results were as follows: 1. The viscosity of CMC solutions was proportional to CMC concentration, with 0.5% CMC solution displaying similar viscosity to stimulated whole saliva. Where as a decrease in contact angle was found with increasing CMC concentration. 2. The viscosity of human saliva was found to be inversely proportional to shear rate, a non-Newtonian (pseudoplastic) trait of biological fluids. The mean viscosity values at various shear rates increased as follows: stimulated parotid saliva, stimulated whole saliva, unstimulated whole saliva, stimulated submandibular-sublingual saliva. 3. Contact angles of human saliva on the tested solid phases were inversely correlated with viscosity, namely decreasing in the order stimulated parotid saliva, stimulated whole saliva, unstimulated whole saliva, stimulated submandibular-sublingual saliva. 4. Boiled CMC dissolved in SSB (CMC-SSB) had a lower viscosity than CMC-SSB (P < 0.01 at shear rate of $90s^{-1}$). 5. For human saliva, contact angles on acrylic resin were significantly lower than those on Co-Cr alloy (P < 0.01). 6. Comparing CMC solutions with human saliva, the contact angles between acrylic resin and human saliva solutions were significantly lower than those between acrylic resin and CMC solutions, including Salivart and Moi-Stir (P <0.01). The effectiveness of CMC solutions in terms of their rheological properties was objectively confirmed, indicating a vital role for CMC in the development of effective salivary substitutes.

• Analytical Science and Technology
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• v.26 no.1
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• pp.73-79
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• 2013

The allyl isothiocyanate, capsaicin and dihydrocapsaicin as main components in self defense sprays were determined by gas chromatography-mass spectrometer (GC-MS). Although self defense spray was used to protect by myself, a social problem could be caused by the hazard of spray chemical due to use pungent liquid. To identify this, the pH of pungent liquid solutions, solubility to detergents, the existence of other materials and the types and amounts of pungent material in spray chemicals were investigated in this work. Finally, the amounts of allyl isothiocyanate, capsaicin and dihydrocapsaicin as pungent materials in them were determined by GC-MS. The pH of chemicals were about 5.7 as weak acid, the detergents can emulsify them with water well. And they did not contain fluorescent materials and hazard organic solvents. The pungent components in three real samples were only allyl isothiocyanate [47,600 mg/kg (47.6%)] in one sample, and mixtures with capsaicin [228 mg/kg~368 mg/kg (1.14%~1.84%)] and dihydrocapsaicin [224 mg/kg~414 mg/kg (1.12%~2.07%)] in the others, respectively.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.207-208
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• 2002

휘발성 유기화학물질 (VOCs)이 인체의 건강에 미치는 영향은 아직까지도 명확하게 밝혀지진 않았지만 대부분의 물질이 재실자에게 자극과 불쾌감을 유발하며, 여러 종류의 발암성 물질을 포함하고 있는 것으로 알려지고 있다 휘발성 유기화학물질 중에서 80% 정도가 인체의 호흡기관을 자극하고 눈의 통증이나 자극을 유발하며, 이중에서 25% 정도는 발암성 물질로 파악되고 있다. (중략)