광조사 방식이 복합레진의 중합과 누출에 미치는 영향

박종진,박정원,박성호,박주명,권태경,김성교 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.2

The aim of this study was to investigate the effect of light irradiation modes on polymerization shrinkage, degree of cure and microleakage of a composite resin. VIP^™ (Bisco Dental Products, Schaumburg, IL, USA) and Optilux 501^™(demetron/ Kerr, Danbury, CT, USA) were used for curing Filtek^™ Z-250(3M Dental Products, St. Paul., MN, USA) composite resin using following irradiation modes: VIP^™ (Bisco) 200mW/cm^2 (V2), 400mW/cm^2 (V4), 600mW/cm^2 (V6), Pulse-delay (200 mW/cm^2 3 seconds, 5 minutes wait, 600mW/cm^2 30seconds, VPD) and Optilux 501^™ (Demetron/Kerr) C-mode (OC), R-mode (OR). Linear polymerization shrinkage of the composite specimens were measured using Linometer (R&B, Daejeon, Korea) for 90 seconds for V2, V4, V6, OC, OR groups and for up to 363 seconds for VPD group (n=10, each). Degree of conversion was measured using FTIR spectrometer (IFS 120 HR, Bruker Karlsruhe, Germany) at the bottom surface of 2 mm thick composite specimens. V2, V4, V6, OC groups were measured separately at five irradiation times (5, 10, 20, 40, 60 seconds) and Or, VPD groups were measured in the above mentioned irradiation modes (n=5, each). Microhardness was measured using Digital microhardness tester (FM7, Future-Tech Co., Tokyo, Japan) at the top and bottom surfaces of 2mm thick composite specimens after exposure to the same irradiation modes as the test of degree of conversion(n=3, each). For the microleakage test, class V cavities were prepared on the distal surface of the ninety extracted human third molars. The cavities were restored with one of the following irradiation modes: V2/60 seconds. V4/40 seconds, V6/30 seconds, VPD, OC and OR. Microleakage was asessed by dye penetration along enamel and dentin marigns of cavities. Mean polymerization shrinkage, mean degree of conversion and mean microhardness values for all groups at each time were analyzed using one-way ANOVA and Duncan's multiple range test, and using chisquare test for microleakage values. The results were as follows: ·Polymerization shrinkage was increased with higher light intensity in groups using VIP^™(Bisco) : the highset with 600mW/cm^2, followed by Pulse-delay, 400mW/cm^2 and 200mW/cm^2 groups. The degree of polymerization shrinkage was higher with Continuous mode than with Ramp mode in groups using Optilux 501^™ (Demetron/Kerr). ·Degree of conversion and microhardness values were higher with higher light intensity. The final degree of conversion was in the range of 44.7 to 54.98% and the final microhardness value in the range of 34.10 to 56.340. ·Microleakage was greater in dentin margin than in enamel margin. Higher light intensity showed more microleakage in dentin margin in groups using VIP^™ (Bisco). The microleakage was the lowest with Continuous mode in enamel margin and with Ramp mode in dentin margin when Optilux 501^™ (Demetron/Kerr) was used.

국립공원 아고산대 독립훼손지 복원식생 분포특성 및 관리방안

김종엽(Jong-Yup Kim),윤주웅(Ju-Ung Yun),한봉호(Bong-Ho Han),곽정인(Jeong-In Kwak),박석철(Seok-Cheol Park),박수영(Su Young Park),정원옥(Won-Ok Jeong) 국립공원연구원 2022 국립공원연구지 Vol.13 No.1

본 연구는 독립훼손지 중 아고산대에 위치한 지리산국립공원 세석평전과 노고단 복원식생지를 대상으로 현존식생 분석 및 식생분포 특성을 파악하여 중장기적인 모니터링 및 관리방안 수립을 위한 기초자료를 제공하고자 수행하였다. 현존식생 조사범위는 훼손지 일대 유역권분포 현황을 고려하여 설정하였으며, 세석평전 조사면적은 55,037㎡, 노고단 조사면적은 166,599㎡ 이었다. 세석평전은 초본층에 의한 식생피복도는 90% 이상 수준으로서 나지노출이 없었고, 관목층의 피복도가 60% 이상으로 안정화되어 있었다. 주요 출현수종은 구상나무, 사스래나무, 쇠물푸레나무, 철쭉, 털진달래, 붉은병꽃나무 등 식재수종과 자연적으로 이입한 자생수종이 생육하고 있었다. 노고단은 신갈나무, 호랑버들, 철쭉, 털진달래, 미역줄나무 등이 우점하는 관목식생지가 52%로 가장 넓게 분포하고 있었고, 전반적으로 식생활착 상태가 양호하였다. 노고단의 원식생은 신갈나무군락으로 추정되었고, 군부대철거지에는 귀화식물이 분포하고 있기 때문에 적극적인 관리가 필요하였다. 연구대상지는 장기적으로 주변 자연식생과 조화로운 식생경관으로 발달할 것으로 예측되었다. 향후 훼손지 복원모델은 인근 지역의 원식생을 고려하여 설정해야 할 것이지만, 복원 달성 목표는 실현가능한 수준의 목표를 설정해야 할 것이다. This study was conducted to provide basic data for mid-to long-term monitoring and establishment of management plans by analyzing the existing vegetation and identifying the vegetation distribution characteristics for the restored vegetation in Nogodan and Seseokpyeongjeon in Jirisan National Park located in the subalpine zone among the independent damaged areas. Actual vegetation survey range was established in consideration of the distribution of the watershed around the damaged area. The surveyed area of Seseokpyeongjeon was 55,037㎡, and the surveyed area of Nogodan was 166,599㎡. In Seseokpyeongjeon, the vegetation coverage by the herbaceous layer was almost 90% or more, there was no bare exposure, and the coverage of the shrub layer was stabilized at 60% or more. The main emerging tree species were planted species such as Abies koreana, Betula ermanii, Fraxinus sieboldiana, Rhododendron schlippenbachii, Rhododendron mucronulatum var. ciliatum, and Weigela florida as well as natively migrated native species. In Nogodan, the shrub vegetation dominated by Quercus mongolica, Salix caprea, Rhododendron schlippenbachii, Rhododendron mucronulatum var. ciliatum, and Tripterygium regelii was the most widely distributed with 52% of the area, and the overall diet was good. The native vegetation of Nogodan was presumed to be a cypress colony. Naturalized plants were distributed in the military base demolition site, so active management was required. The study site was predicted to develop into a vegetation landscape in harmony with the surrounding natural vegetation in the long term. In the future, the restoration model for damaged areas should be set in consideration of the native vegetation of the nearby area, but the goal to achieve restoration should be set at a feasible level.

[논문]Operational Characteristics of CO2 Laser Adopted by Superposing-Discharge

Hee-Je Kim,Hyun-Ju Chung,Byoung-Dae Min,Jong-Han Joung,Sung- lun Park 釜山大學校生産技術硏究所 2003 生産技術硏究所論文集 Vol.62 No.-

오늘날 현저한 CO2 레이저의 응용 추세에 발맞추어 보다 다양한 형태의 출력 제어 기술이 대두되고 있다. 본연구에서는multi-Pulse Superposing-Discharge 기술을 이용하여 다양한형태의 CO2 레이저의 펄스를 성형 하였다. 펄스 성형을 위한 방법으로 PIC one-chip microprocessor를 이용하여 삼중 PFN 모률의 SCR을 각각 고유의 지연시간을 가지도록 제어하였다. 실험에 사용된 삼중 PFN 모률의 전원 회로는 각각 캐패시터 인덕터,SCR,고압 펄스 트랜스 그리고 고압 트랜스 2차측에 브릿지 정류기로 구성 하였다. 고압 펼스 트랜스의 1차측을 제어하므로서 PFN 모률의 동작을 저 전압에서 수행 할 수 있다. 트랜스의 2차측에 연결된 전파 정류기는 펄스 에너지를 부하에 지속적으로 전달한다. 본 연구에서는 삼중 PFN 모률의 각각의 SCR을 다른 시간 가격을 두고 트리거 하므로서 다양한 Long pulse shaping을 실현하였다. 또한 약 250-1000μs 의 주기를 가지는 다양한 펄스형 레이저 빔을 얻었다.

주파수의존형 전자근관장측정기의 정확도에 관한 연구

박주현,노병덕,이승종 大韓齒科保存學會 1996 Restorative Dentistry & Endodontics Vol.21 No.1

흰쥐 시상에서 Epidermal growth factor receptor면역반응 신경세포의 생후 발달에 관한 연구

박영란,정윤영,김종중,문정석,오재욱,정영욱,김주수 조선대학교 2003 The Medical Journal of Chosun University Vol.28 No.1

Background and Objectives : Epidermal growth factor receptor (EGFR), a 170-kDa transmembrane glycoprotein, appears to mediate epidermal growth factor (EGF) activity. Transforming growth factor-α and EGF produce their biological effects in numerous systems by stimulating the EGFR In this study, we examine the postnatal development of EGFR immunoreactivity in the different regions of the thalamus of the rat Materials and Methods : The present study is based on 28 postnatal cases of rat thalamus ranging from the day of birth, postnatal day 0 (P0) to 30 days (P3, P5, P10, P15, P20, P30), and these cases were compared with adult rat thalamus. Cryostat sections were processed free-floating with monoclonal antibody by immunohistochemistry Results : EGFR immunoreactivity in the thalamus of the rat showed very different patterns according to postnatal ages and thalamic areas. EGFR-immunoreactive cells appeared in the first two postnatal weeks, except the ventral posterior thalamic nuclei. In the early postnatal days, EGFR-immunoreactive cells appeared thalamic midline structures, increased progressively in the first two postnatal weeks, and followed mediolateral gradient. The mature patterns of EGFR-immunoreactive cells were achieved at P20 Conclusion : These data indicate that the maturation of EGFR-immunoreactive cells requires a relatively prolonged period of time to achieve an adult configuration. Many growth factors probably play protective or neurotrophic roles at EGFR-immunoreactive neurons of thalamus both young and adult rats In addition to difference in time of appearance in thalamic nuclei and developing pattern with mediolateral gradient suggest that EGFR-immunoreactivities are correlated with the appearance of the related functional.

포퓰리즘, 데모스, 급진민주주의 - 라클라우와 무페에게서 ‘인민’의 담론적 구성에 관하여 -

한상원 한국철학사상연구회 2020 시대와 철학 Vol.31 No.2

오늘날 정치에 관한 사유들은 포퓰리즘이라는 현상을 비껴갈 수 없을것이다. 그런데 포퓰리즘을 둘러싼 관점들은 종종 양극단의 대립을 드러낸다. 포퓰리즘은 일종의 우려할만한 사건인가, 아니면 그 자체로 필수불가결한 민주주의 사회의 근본 전제인 것일까? 다시 말해, 포퓰리즘의 세계적확산은 오늘날 현대 사회를 파국으로 밀어넣을 것인가, 아니면 그 안에서 새로운 희망을 발견할 수 있을 것인가? 2018년 프랑스 파리에서 일어난 노란조끼 운동은 무엇을 반복하고 있는가? 1789년 7월 14일의 성난 군중인가, 아니면 1923년 11월 9일의 뮌헨 맥주집 폭동일까? 그들은 혁명의주체 프롤레타리아인가, 아니면 폭민인가. 혹은 둘 다일까? 이와 같은 논의는 근본적으로 민주주의의 주체로 상정되는 인민 혹은 데모스의 범주를 어떻게 이해할 것인가와 직접 관련되어 있다. 본 논의는 ‘포스트 맑스주의’를선언하며 급진민주주의 전략을 제시한 라클라우와 무페가 포퓰리즘에 관해도발적으로 제기하고 있는 정치철학적 사유를 소개하면서, 그 의미와 성과, 그리고 한계를 지적하고자 한다. Thoughts on politics today are not able to avoid the phenomena of populism. The perspectives on the populism often reveal the opposition between two extremes. Is populism a sort of worrisome event, or is it an inevitable fundamental precondition of democratic society? Is the global spread of populism going to drive modern society into catastrophe, or can we find new hope in it? What did the yellow vest movement repeat in Paris in 2018? Was it the raging crowd on July 14, 1789, or the Munich brewery riot on November 9, 1923? Are they the proletarians of the revolution or the mobs? Or is it both? This discussions are directly engaged to how to understand the categories of People or Demos, which is regarded as the subject of democracy. In this article, I will try to show the meaning, achievements, and limitations of Laclau and Mouffe, who proclaimed ‘Post Marxism’ and suggested the strategy of radical democracy, proposing the political philosophy of populism.

培養鷄胚筋細胞分化에 미치는 細胞融合促進物質의 영향

朴映淳,朴鍾君,金賢玉,金鍾鎬,李東燁,金完柱 圓光大學校 1988 論文集 Vol.22 No.2

培養鷄胚筋細胸 分化에 미치는 促進物質의 영향을 알아보고자 2가양이온 (Ca2+, Mg2+) 胸胚抽出物 (EE), polyethylene glycol (PEG), 再生中인 도마뱀 (Lacertilia)꼬리 추출물 (BE)을 처리하여 細胸融合指數를 비교 조사하였다. 정상배양시의 細胸融合指數는 배양시작 70 시간에 최대에 달했으며 더이상 증가하지 않았고, Ca2+와 Mg2+ 처리할 경우에는 농도가 증가할수록 細胸融合指數는 저하되고, 근세포의 굵기도 정상세포보다 가늘고 핵이 모여있었다. Polyethylene Glycol (PEG)와 Blastemata Extract (BE) 처리군에서는 대조구와 큰 차이가 없는 것으로 나타났다. 鷄胚抽出物 (EE) 을 筋細胞分化에 필수적이나 과량으로 添加시에는 細胞融合은 억제되고 세포수는 증가되는것으로 나타났다. To study the effects of promoting factors on the differentiation of muscle cells, chick embryonic myoblasts were cultured with divalent cations (Ca2+, Mg2+) Chick embryo extract (EE), Polyethylene Glycol (PEG) and Blastema extract of Lacertilia (BE). Fusion index and Growth ratio were measured at various culture time. The fusion index of normal myoblast culture was reached maximum at 70 hours and the divalent cations (Ca2+, Mg2+) treated groups were decreased at higher concentration. The cellular formation of myoblasts treated with divalent cations was thiner and more aggregated between nuclei than that of normal myoblasts calture was. When polyethylene glycol (PEG) and Blastema extract of Lacertilia (BE) were treated to the myoblasts, tha fusion indices were similar to the control. Embryo Extract (EE) was seemed to be necessary for the fusion of chick embryonic myoblasts in culture, however, when excess of EE was added the fusion index was decreased and the number of cells was increased.

역도 지도자의 리더십 유형이 선수의 운동 몰입과 경기력에 미치는 영향

박종진, 이선주 忠北大學校 平生體育硏究所 2014 平生體育硏究所 論文集 Vol.26 No.-

The purpose of this research is to investigate the effects of weight-lifting coaches’ leadership style on player dedication and athletic performance, improve field application, provide base data for teaching weight-lifters, and enhance athletic performance. To achieve this, surveys were conducted on 250 male and female weight-lifters of middle and high schools who are registered in Korean Weight-lifting Federation in 2014. The surveys focused on coaches’ leadership style, weight-lifter dedication, and their athletic performance. To investigate the difference of dedication and athletic performance according to general characteristics, collected questionnaires were analyzed by frequency analysis, independent sample t-test, one-way ANOVA, Pearson’s Correlation Analysis, and standard multiple regression analysis. The level of significance was set as α=.05. And through the above method and procedure, the conclusions were obtained as follows. First, significant differences were found in the subjects’ dedication according to general characteristics, and the sub-factors of athletic performance by the school level. Significant differences were found in clear objective, instrumental experience and entrancement, which are the sub-factors of dedication by gender, and concentrated performance in the athletic performance by gender. Moreover, significant difference were found in the athletic performance and the concentrated performance in relation to athletic performance record, and the sub-factor of athletic performance by grade. The sub-factors of clear objective, instrumental experience, and athletic performance according to career also showed significant differences. Second, the effect of weight-lifting coaches’ leadership style on the weight-lifter dedication, the training and coaching behavior, which are the sub-factors of coaches’ leadership style, had a positive effect on the weight-lifter dedication. Democratic and affirmative feedback also had a positive effect on clear objective, instrumental experience, and entrancement. Authoritarian behavior had a negative effect on clear objective and instrumental experience, but had a positive effect on self-control capability and transformation of sense of time. Third, the effect of weight-lifting coaches’ leadership style on the weight-lifters’ athletic performance, democratic and affirmative feedback, which is a sub-factor of weight-lifting coaches’ leadership style, had a significant effect on concentrated performance. Authoritarian behavior, however, had a negative effect on concentrated performance, but had a positive effect on athletic performance. Lastly, the effect of dedication on athletic performance, clear objective and instrumental experience, which is the sub-factor of dedication, had a positive effect on concentrated performance and self-control capability, and a significant effect on athletic performance. Entrancement had a positive effect on concentrated performance, but transformation of sense of time had a negative effect on concentrated performance.

잇솔질 마모 처리한 불소방출성 수복재의 특성

박종하,백병주,김재곤,양연미 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.4

불소는 항우식 작용을 보이므로 치아의 우식예방을 고려한 진료가 이루어지면서 치면에 불화물을 도포하거나 불소 함유 구강세정액을 사용하거나 불소방출성의 수복재료를 적용하거나 하는 등의 우식억제 방법이 치과임상에서 빈번하게 적용되고 있다. 이에 본 연구는 불소 방출을 보이는 수복재료의 잇솔질 후 불소방출과 잇솔질로 인한 표면조도의 변화를 조사하기 위해 시행되었다. 7종의 불소를 방출하는 수복재료로 Fuji Ⅱ LC Improved: FL, Compoglass F: CG, Dyract AP: DR, F2000: FT, Ariston: AT, Tetric: TR, 그리고 Gradia: GD를 연구재료로 사용하였다. 불소 방출은 10,000회의 잇솔질을 시행한 후 10일 동안의 방출량을 측정하였고, 표면조도는 40,000회의 잇솔질 후 중심선평균거칠기 Ra와 최대거칠기 Ry를 측정하였으며, 마모면은 주사전자현미경으로 관찰하였다 잇솔질 후의 불소 방출량과 표면 관찰로부터 다음과 같은 결론을 얻었다. 1. 불소방출은 AT군, FL군 및 CF군의 경우에는 초기단계에 다량의 급격한 방출을 보인 후 상대적으로 낮으면서도 지속적인 방출 양상을 보였지만, 나머지 시험의 경우에는 초기단계로부터 낮으면서도 지속적인 방출을 보였다. 2. 불소방출은 약 40일 경과 후 안정적인 방출 양상을 나타냈으며, Tukey 분석 결과, AT군, 레진강화 GIC의 FL군, 콤포머군 전부 및 불소방출성 콤포짓트 레진의 GD군과 TC군 사이에서 통계학적으로 방출량의 유의한 차이를 보였다(p<0.05). 3. 표면조도는 FT군에서 가장 크고 CF군에서 가장 작은 값을 보였으며, Tukey 분석 결과, FT군, AL군 및 FL군과 TC군, DR군, GD군 및 CF군 사이에서 통계학적으로 유의한 차이를 보였다(P<0.05). The objectives of this study were to evaluate the fluoride release and the change of surface roughness of fluoride releasing restorative materials after toothbrush-dentifrice abrasion. Seven commercially available fluoride releasing restorative materials (Fuji Ⅱ LC Improved: FL, Compoglass F: CG, Dyract AP: DR, F2000: FT, Ariston: AT, Tetric: TR, and Gradia: GD) were selected as experimental materials. The results obtained were summarized as follows: 1. The AT, FL, and CF groups produce an initially large burst of fluoride release and comparatively low but continuous release of fluoride. But other groups produce no initial burst of fluoride and levels of release remain relatively constant. 2. The rate of fluoride release remains steady state after 40 days. The results of Tukey's test (P<.05), the fluoride release showed the order of decreasing rank as follows: AT > FL > compomers > TC and GD. 3. The surface roughness indicated that the highest value was observed in the FT group and the lowest value was observed in the CF group. The surface roughness of Tukey's test showed the significant differences between groups of FT, AT and FL and groups of CF, DR, GD and TC (P<0.05).

N-Benzoyl-4(5)-nitroimidazole의 가수분해반응에 대한 속도론적 연구

박국애,정윤주,이종팔 東亞大學校 2000 東亞論叢 Vol.37 No.-

The rate constants for the hydrolysis of N-benzoyl-4(5)-nitroimidazole were determined in water at the 25℃ under pseudo first order conditions by uv/vis spectrophotometer. The pH independent reaction and the hydroxide ion catalyzed reaction were observed from pH 6 to 1 and above pH 6, respectively. The D2O solvent isotope effect couldn't observe in the pH independent reaction, that is, k0 H₂O/k0 D₂O 1.0. Activation parameters in the water catalyzed reaction were calculated to △H‡ =12.3 Kcal and △S‡ = -32.6 e.u. respectively. Thus, the water catalyzed reaction is more important to nucleophilic attack to the carbonyl carbon than the protonation of the leaving group In the transition state. Above pH 6 the hydrolytic reaction showers hydroxide ion catalyzed reaction.