• Journal of dental hygiene science
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• v.17 no.6
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• pp.481-486
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• 2017

The study aimed to compare the whitening efficacy of a strip and gel containing 2.9% hydrogen peroxide, using a tooth whitening light activator. The whitening effect was compared through in vitro and in vivo studies. In the in vitro study, we used stained hydroxyapatite (HAP) specimens as artificial teeth. HAP specimens were made using HAP powder and polyvinyl alcohol solution, and stained by modified Stookey's method. A whitening gel and whitening strip were applied to the respective specimens for 20 minutes, with a light activator. The color changes were measured using a colorimeter. In the in vivo study, one group (test 1) used the gel with a light activator and the other group (test 2) used a strip with the same activator for 15 minutes a day, for four consecutive days. An organoleptic evaluation using a Vita shade guide and instrumental evaluation using a Shade eye-NCC (Shofu Co., Japan) were performed. The color change values (${\Delta}E^*$) in the in vitro study revealed the strip with the light activator to be more effective than the gel with the same activator (p<0.001). In the in vivo study, even though there was no significant difference between the groups with respect to the ${\Delta}E^*$, using either the Shade eye-NCC or the Vita shade guide, the change in yellowness (${\Delta}b^*$) was statistically significant (p=0.024). In conclusion, test 2 group that used 2.9% hydrogen peroxide strip with a light activator, showed a tendency towards increased whitening than test 1 group that used the gel with the same activator; however further studies are needed to validate the above finding.

• Journal of dental hygiene science
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• v.15 no.6
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• pp.794-799
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• 2015

In recent years, there has been a global trend toward the importance of natural extracts for the prevention and treatment of human diseases. ${\beta}$-glucan is known to have anti-inflammatory activity, anti-cancer, and improvement of immune system. Polycan is purified ${\beta}$-glucan from Aureobasidum pullulans SM-2001. The anti-cancer effects of ${\beta}$-gluconsan calcium, polycan and calcium gluconate complex, were evaluated in human oral cancer YD-10B cells. YD-10B cells were cultured in the presence of 0, 0.5, 0.75, 1 mg/ml ${\beta}$-gluconsan calcium for 48 hours. MTT assay, cell counting, and observation of cell morphology were conducted. The number of cells decreased and cell morphology changed in the 0.5 mg/ml of ${\beta}$-gluconsan calcium. Almost all cells were dead in the 0.75 and 1 mg/ml. MTT assay showed a dose-dependent reduction in cell proliferation (p<0.05). These results indicate that ${\beta}$-gluconsan calcium exhibiting anti-cancer effects in YD-10B cells through changes in cell morphology and cell death.

• Journal of dental hygiene science
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• v.15 no.3
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• pp.295-300
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• 2015

Odontoclasts and osteoclasts resorb tooth root and alveolar bone, respectively. Many studies have focused on osteoclast formation in periodontitis, but effect of periodontitis on odontoclast formation is not clearly clarified. In this study, we observed formation of odontoclasts as well as osteoclasts in rats with ligature-induced periodontitis. To induce periodontitis, ligatures were placed around the first molars in left mandibles of rats. Rats were sacrificed at days 1, 3, and 10 after ligation. After tartrate resistant acid phosphatase (TRAP) staining in mandible section, the number of TRAP-positive odontoclasts and osteoclasts were histologically counted along the root and the alveolar bone surfaces of tooth, respectively. Odontoclasts increased until day 10 in mesial and furcation root surface, but did not increase in distal root surface. When compared odontoclast formation to osteoclast formation in mesial surface, osteoclasts peaked at day 3, and then decreased gradually, whereas odontoclasts were continuously increased until day 10. The number of odontoclasts was lower than that of osteoclasts before and after periodontitis induction. These indicate that periodontitis increased formation of odontoclasts as well as osteoclasts, but odontoclast formation occurs slower and weaker than that of osteoclasts.

• Journal of Life Science
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• v.19 no.8
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• pp.1139-1144
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• 2009

It has been known that brassiolide (BL) increased the positive gravitropic response and ethylene production in maize roots. This study examined the relationship between the BL-induced gravitropic response and ethylene Production. The ethylene production was inhibited to about 90% of the control by the treatment of $10^{-4}$ M aminoethoxyvinylglycine (AVG), the ethylene synthesis inhibitor. However, the gravitropic response did not show any significant changes compared to the control at $10^{-4}$ M AVG. In the case of treatment of AVG with BL, the ethylene production decreased to 60% of the control. However, the gravitropic response increased to the level which was induced by BL. Cobalt ions, another ethylene biosynthesis inhibitor, inhibited ethylene production, but not gravitropic response. When roots were treated with BL and cobalt ions, they showed the inhibition of ethylene production and promotion of gravitropic response. To elucidate the possibility that the effect of BL is related to auxin transport, roots were treated with TIBA (2,3,5-triiodobenzoic acid), an auxin transport inhibitor. Both treatment of TIBA alone and TIBA with BL stimulated ethylene production to about 96% and 132%, respectively. However, gravitropic response was completely inhibited in both treatments. Further, roots treated with BL in the presence of TIBA and IAA showed a negative gravitropic response, which means that IAA accumulates in the upper side of horizontal roots. Root elongation was also stimulated in this treatment. Taken together, these results suggest that BL might affect the differential distribution of internal IAA on roots, causing the regulation of positive gravitropic response.

• Journal of Life Science
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• v.26 no.9
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• pp.1097-1104
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• 2016

With the development of next generation sequencing (NGS), large numbers of transcriptional molecules have been discovered. Most transcripts are non -coding RNAs (ncRNAs). Among them, long non-coding RNAs (lncRNAs) with more than 200 nucleotides represent functional RNA molecule that will not be translated into protein. In plants, lncRNAs are transcribed by RNA polymerase II (Pol II) or Pol III, Pol VI and Pol V. After transcription of these lncRNAs, more RNA processing mechanisms such as splicing and polyadenylation occurs. The expression of plant lncRNAs is very low and is tissue specific. However, these lncRNAs are strongly induced by specific external stimuli. Because different external stimuli including environmental stresses induce a large number of plant lncRNAs, these lncRNAs have been gradually considered as new regulatory factors of various biological and development processes such as epigenetic repression, chromatin modification, target mimicry, photomorphogenesis, protein relocalization, environmental stress response, pathogen infection in plants. Moreover, some lncRNAs act as precursor of short RNAs. Although a large number of lncRNAs have been predicted and identified in plants, our current understanding of the biological function of these lncRNAs is still limited and their detailed regulatory mechanisms should be elucidated continuously. Here, we reviewed the biogenesis and regulation mechanisms of lncRNAs and summarized the molecular functions unraveled in plants.

• Journal of Acupuncture Research
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• v.31 no.1
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• pp.177-186
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• 2014

Objectives : The aim of this study is to report a case of a 51-year-old patient with Herpes zoster, whose symptoms were relieved within five weeks after the East-west medical combined treatment. Methods : A Herpes zoster patient with extreme pain around the right lower ribs and lower back was admitted into the Korean medicine hospital. Bee venom acupuncture was applied directly onto the site of pain and electroacupuncture was applied on $GV_6-BL_{20}$, inferior site of spinous process of the 12th thoracic vertebra-$BL_{21}$, $GV_5-BL_{22}$, $GV_4-BL_{23}$ six times a week. Moxibustion was applied on $BL_{49}$, $BL_{50}$, $BL_{51}$, $BL_{52}$, $GB_{25}$, $LR_{13}$ six times a week, and the patient took daily doses of herbal medicine and western medicines such as anticonvulsants, analgesics, antiepileptics. The patient's symptoms were evaluated with numeric rating scale(NRS) and neuropathic pain scale(NPS). Results : The results were as follows: 1. After the East-west medical combined treatment, the NRS grade decreased from 8 to 1. 2. On the neuropathic pain scale, the patient's symptoms changed from deep sharp pain and burning sensation to superficial dull pain and coldness. Sensitivity to touch, discomfort, and itchiness also decreased. Sudden attacks of pain appeared 14 to 21 days after onset, but disappeared after final treatment. Conclusions : The results of the above patient suggests that the East-west medical combined treatment may be effective for total remission of herpes zoster. Further research is needed to confirm such effects.

• Journal of Acupuncture Research
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• v.30 no.4
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• pp.139-149
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• 2013

Objectives : The aim of this study was to observe the effect of balanced acupuncture on herniated intervertebral disc of lumbar spine patients. Methods : We investigated 23 cases of in-patients with acute & subacute herniated intervertebral disc of lumbar spine in oriental hospital, and divided patients into two groups. We treated one group(12 people) by complex oriental medical treatment with Balanced acupuncture, and the other group(11 people) by complex oriental medical treatment without Balanced acupuncture. To evaluate the effectiveness of treatment applied for two groups, we used visual analog scale(VAS) and rating scale for low back pain at admission and discharge. Results : 1. In balanced acupuncture group and control group, compared with baseline and final. VAS was significantly improved. 2. In Balanced acupuncture group and control group, compared with baseline and final. Rating scale for low back pain was significantly improved. 3. VAS and rating scale for low back pain improvement rate in balanced acupuncture group were no statistical significance compared with control group. Conclusions : Balanced acupuncture might be used for relieving symptoms related with herniated intervertebral disc of lumbar spine, but it's no statistical significance.

• Food Science and Preservation
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• v.14 no.5
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• pp.487-491
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• 2007

This study was conducted to investigate the effect of treatment with squeous chlorine dioxide and hot water on the germination of radish (Raphanus sativus L.) seeds, and reduction of microbial load on the seeds. Increases in treatment and the concentration of aqueous chlorine dioxide in water resulted in increasing reductions in the counts of total aerobic microbes. Seeds treated with aqueous chlorine dioxide (100 ppm/20min, 200ppm/20min) showed about a 10-fold decrease in microbial loads. Germination of seeds was not adversely affected by any treatment tested, although the germination rate of seeds in the group treated at $55^{\circ}C$ for 20 min was reduced by 10% compared to that of control. Combined treatment with hot water and aqueous chlorine dioxide yielded better out comes in both microbial reduction and seed germination rate than did single treatments. A combined treatment with 100 ppm aqueous chlorine dioxide and hot water($45^{\circ}C$ or $50^{\circ}C$) resulted in about a 100-fold decrease in microbial load whereas germination rate showed only a slight increase to $97.0{\sim}97.7%$. Total aerobic microbial counts in radish seeds were decreased by aqueous chlorine dioxide and hot water treatment in the order. aqueous $CIO_2$+ hot water > aqueous $CIO_2$ > chlorinated water > hot water > control.

• Journal of The Korean Association For Science Education
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• v.33 no.6
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• pp.1248-1258
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• 2013

This study investigated the elementary school students' perception of the "purpose of scientists' experiments" and discovered what roles teachers can take to provide guidance. The study subjects were 193 elementary school students (96 boys and 97 girls) in a school located in Gyeonggi-do. The responses were analyzed through categorization based on their gender, science test score at school, and understanding of the purposes of scientific experiments based on students' choice of science-related future careers. The results of this study were as follows. In relation to the purpose of science experiments, the elementary school students considered intrinsic values of doing experiments more valuable than their extrinsic values. Next, 34.2% of the students answered that scientists do science experiment 'to find a new fact' and 26.9% of the students answered 'to make life convenient.' The results showed that girls responded 'social usefulness' more frequently than boys. Considering the achievement levels, it was found that high level students replied 'to make life convenient' more frequently than middle and low level students on why scientists do science experiments. Students who want to have a science-related career had varied ideas about it.

• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.35-44
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• 2016

Various risk factors are known to be the nature of construction project execution process. These factors lead to potential claims, dispute mediation, arbitration, and litigation which can result in huge loss of money and time. Therefore, it is necessary for construction companies in Korea to improve overall project management capability through the evaluation before entering into the overseas construction market. Also, after examination of the claim and dispute caused by construction project risks, a substantial degree of influence and active preparation for the claim and dispute management should be confirmed via the effect analysis of the each factors. Main claim causes were derived through claim and dispute cases involved with domestic construction projects. As a prediction result of the main claim, 16.1% of the construction change claim, 5.7% of the bad faith claim and 2.7% for the construction delay claim were found to be the portion of the total construction cost. As a result of this analysis, risk management methodology was suggested to improve a project management capability for domestic construction companies through analysis result of the main factors of construction claims.