• Journal of Periodontal and Implant Science
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• v.28 no.4
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• pp.703-721
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• 1998

In order to observe the effects of Nicotine and NNK on cultured human gingival fibroblast, several factors were examined including mutagenicity, the number of cells attached culture plate surface through MTT test, the abundance of collagen & collagenase in mRNA level and collagenolytic activity in extracellular matrix. The results were as follows; 1. Regardless of the co-existence of S9, Nicotine did not show the mutagenicity by itself and NNK by itself showd the same result; However, dose related mutagenicity was shown in NNK with S9. 2. The number of fibroblasts attached cultured plate surface was measured by MTT procedure. The number of cells in Non-smokers increased at all time periods as compared to those of smoker. 3. Non-smoker's fibroblast treated by NNK or Nicotine was dosedependently dosedependently decreased in the number of cells when compared to untreated control. In higher dose, Nicotine showed the cellular toxicity, but NNK did not. 4. No change in the abundance of mRNA for pro${\alpha}1$ and pro${\alpha}2$ was shown in Nicotine treated group but in gingival fibroblasts following treatment with NNK, the abundance of mRNA for pro${\alpha}1$, but not pro${\alpha}2$ collagen was decreased. 5. The abundance of mRNA for collagenase was decreased when NNK was treated but no change occurred in Nicotine treated group. 6. The effect of NNK and Nicotine in collagenolytic activity showed that, collagenase activity exclusively react to type I collagen, was increased in both group, but gelatinase exclusively react to type IV collagen was not influenced at all. Collagenase activity of smoker's fibroblast was also increased as much as Nicotine and NNK group. The findings suggest that both of Nicotine and NNK lead gingival fibroblast to decrease in the abundance of collagen. And it seems to be that Nicotine and NNK have independent pathway toward the gingival fibroblast.

• Bulletin of Korea Environmental Preservation Association
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• v.28 s.365
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• pp.54-56
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• 2006

회원사 및 배출사업장 환경기술인 및 관리자분들의 환경관리업무에 도움을 드리고자 자주 질의ㆍ문의ㆍ상담되는 환경관리 질의응답 사례를 게재하오니 참고하시기 바랍니다.

• Bulletin of Korea Environmental Preservation Association
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• v.28 s.364
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• pp.56-57
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• 2006

회원사 및 배출사업장 환경기술인 및 관리자분들의 환경관리업무에 도움을 드리고자 자주 질의ㆍ문의ㆍ상담되는 환경관리 질의응답 사례를 게재하오니 참고하시기 바랍니다.

• Parasites, Hosts and Diseases
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• v.36 no.4
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• pp.261-268
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• 1998

The present study was undertaken to investigate the role of cysteine proteinase of Trichomonas vaginalis in escaping from host defense mechanism. A cysteine proteinase of T. vaginalis was purified by affinity chromatography and gel filtration. Optimum pH for the purified proteinase activity was 6.0. The proteinase was inhibited by cysteine and serine proteinase inhibitors such as E-64, NEM, IAA, leupeptin. TPCK and TLCK, and also by $Hg^{2+}$, but not affected by serine-, metallo-, and aspartic proteinase inhibitors such as PMSF, EDTA and pepstatin A. However, it was activated by the cysteine proteinase activator, DTT. The molecular weight of a purified proteinase was 62 kDa on gel filtration and 60 kDa on SDS-PAGE. Interestingly, the purified proteinase was able to degrade serum IgA, secretory IgA, and serum IgG in time- and dose-dependent manners. In addition, the enzyme also degraded hemoglobin in a dose-dependent manner. These results suggest that the acidic cysteine proteinase of T. vaginalis may play a dual role for parasite survival in conferring escape from host humoral defense by degradation of immunoglobulins, and in supplying nutrients to parasites by degradation of hemoglobin.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.04a
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• pp.475-478
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• 2011

지금까지 음악 정보 검색을 위한 다양한 내용 기반 음악 검색 및 비교 방법이 제안되었다. 그런데, 기존 연구들은 질의 방식 및 검색 카테고리가 변화함에 따라 상이한 방법을 제시하고 있어 음악 검색 방법을 통합하는 데에 한계가 있다. 이러한 문제를 해결하기 위해, 본고에서는 내용 기반 음악 검색의 일반화를 위한 내용 기반 음악 요소 검색(CBMER) 방법을 제안하였다. 제안 방법에서는 확률적 은닉 성분 분석(PLCA)을 사용하여 음원을 분해하고, 각 분해 요소로부터 오디오 특성을 추출하였다. 제안 방법을 사용하여 다양한 질의 방식 및 검색 카테고리로 내용 기반 음악 요소 검색이 가능함을 보이기 위해, 남성/여성의 목소리로부터 질의를 생성하여 목소리 성별에 따른 음악을 검색하는 실험을 수행하고 그 결과를 분석하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.706-711
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• 1992

Silkworm larvae protein concentrate was partially hydrolyzed at $50^{\circ}C$ by papain at pH 2.0 and pepsin at pH 7.0 for 10min and 60min and the effect of enzymatic modification on the functional properties of silkworm larvae protein concentrate was examined. The degrees of hydrolysis measured by TCA-soluble nitrogen content were 10.2% and 19.2% when hydrolyzed by pepsin for 10min and 60min. The nitrogen solubility in water and 0.03M $CaCl_2$ was increased with increasing the degree of hydrolysis, and bulk density, water and oil absorption were also enhanced by enzymatic hydrolysis when compared with the control.

• Journal of Korea Spatial Information System Society
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• v.7 no.1 s.13
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• pp.13-24
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• 2005

Objects, which change their positions over time such as cars, are called moving objects. Trajectories of a moving object have large volumes because trajectories are accumulated. Efficient indexing techniques for searching these large volumes of trajectories are needed in the moving object databases. Especially the TB-tree which supports bundling trajectories is suitable for processing combined queries which have 2 steps: first step is selecting trajectories (range search), next is selecting the parts of each trajectory (trajectory search). But the TB-tree has unnecessary disk accesses cause of lack of spatial discrimination in range queries. In this paper, we propose and implement the splitting polity which can reduce dead spaces of non-leaf node in order to process range queries efficiently. The policy has better performance about range queries than the TB-tree as well as the advantages of the TB-tree, such as highly space utilization and efficient trajectory extraction. This paper shows that the newly proposed split policy has better performance in processing the range queries than that of the TB-tree by experimental evaluation.

• Journal of Convergence for Information Technology
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• v.11 no.9
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• pp.182-190
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• 2021

Rehabilitation dog-walking can be used to improve physical activity and restore QOL in stroke patients. This study investigated the effect of rehabilitation dog-walking on the QOL and physical activity of stroke patients. Twenty-four stroke patients were recruited for this study. Twenty-four stroke patients were randomized 1:1 into two groups. The evaluator measured stroke specific-quality of life (SS-QOL), six minute walk test, and maximal grip strength on the affected and non-affected side. The experimental group received gait training with a rehabilitation dog for 30 minutes once a week for 8 weeks. As a result of the study, there was a significant increase in SS-QOL, six minute walk test, and maximal grip strength on the affected side in the experimental group after the intervention. In addition, the experimental group showed significant improvement in SS-QOL, six minute walk test, and maximal grip strength on the affected side than the control group. Rehabilitation dog-walking may be an intervention method that can improve QOL and physical activity after stroke.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.227-236
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• 2009

The purpose of this study is to examine the acidity of beverages that are sold for children in the market and to estimate by experiment the degree of the enamel erosion of deciduous teeth that is attributed to the beverages. The pH value of children beverages among top sale list in Seoul and Gyeonggi province were measured. And 7 beverages with the pH value of 3.5 or lower were selected. The enamel erosion of deciduous teeth by the children beverages for 1, 5, 10, and 30 minutes respectively was examined. The results were as follows: 1. The acidity of most of the children beverages examined in this study was the pH level of 5.5 or lower that can cause the tooth erosion. 2. The microhardness value of the enamel of deciduous teeth was lower as exposing it to children beverages. The reduction of surface microhardness value was significant from 1 minute after the exposure, and the reduction was continuously observed until 30 minutes has passed. 3. The higher the acidity of beverages, the larger the reduction in microhardness value caused after the exposure of 30 minutes to the beverages. There was no significant relation between the acidity of beverages and the reduction rate of surface microhardness value. The other factors such as calcium, phosphorus, and fluorine or buffering of the beverages may affect the enamel erosion.

• 대한치주과학회:학술대회논문집
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• 1998.11a
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• pp.29-30
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• 1998