Collagenase와 esterase가 상아질 접착강도와 nanoleakage에 미치는 영향

정영정,한세현,김종철,이상훈,김정욱,김영재,장기택 大韓小兒齒科學會 2008 大韓小兒齒科學會誌 Vol.35 No.3

본 연구는 상아질 접착계면에서 collagenase와 esterase가 접착강도와 극미세누출에 미치는 영향을 살펴보기 위해 시행하였다. 발치된 치아의 교합면 상아질에 Single Bond 2(SB)와 Clearfil SE bond(SE)를 사용하여 상아질-레진 접착시편을 제작하고,시편을 인산완충용액(PBS)에 24시간(I),또는 PBS(II),collagenase 용액(III),esterase 용액(IV)에 4주간 보관 한 후 질산은 용액으로 염색하였다. 시편의 미세인장접착강도(μTBS)와 질산은 침투 면적을 측정하여 다음과 같은 결과를 얻었다. 1. SB군의 접착강도가 II∼IV군에서 SE군에 비해 낮은 값을 나타내었다(p<O.05). SB군은 II∼IV군의 접착강도가 I군에 비해 낮은 값을 보였으나(p<O.05),SE군의 접착강도는 I∼IV군간에 차이를 보이지 않았다(p>O.05). 2. SB군의 질산은 침투 면적이 SE군에 비해 높았으며(p<O.05),SB군과 SE군에서 질산은 침투 면적은 I ∼ IV군간에 차이를 보이지 않았다(p>O.05). 3. 접착강도와 질산은 침투 면적은 SE군의 I, II,III군에서 음의 상관관계를 보였다(p<O.05). The purpose of this study was to evaluate the effects of collagenase and esterase on dentin bond strength and nanoleakage. Resin composites were bonded to occlusal dentin of premolars with Single Bond 2(SB) and Clearfil SE Bond(SE). After the microtensile specimens were prepared and stored in PBS for 24 hours(I) or, PBS(II), collagenase(III), esterase(IV) solution for 4 weeks, the specimens were stained with silver nitrate solution. Microtensile bond strength(μTBS) and silver penetration area were measured and, the results were as follows: 1. For group II, III, and IV, the bond strengths of SB were lower than those of SB(p<0.05). The bond strengths of SB II, III, and IV were lower than that of SB I(p<0.05). There was no difference among the bond strengths of SE I ∼ IV groups(p>0.05). 2. Silver penetration areas of SB were higher than those of SE for all storage groups(p<0.05). In SB and SE groups, there was no significant difference of silver penetration area among I ∼ IV groups(p>0.05). 3. SE I, II, and III showed inverse relationship between the bond strengths and the silver penetration areas(p<0.05).

Highly transparent poly(glycidyl methacrylate-co-acryloisobutyl POSS) for 100 μm-thick submicron patterns with an aspect ratio over 100

Kim, Kwanghyun,Yu, Sunyoung,Kim, Sung-Wook,Kim, Taegeon,Kim, Sang-Min,Kang, Se-Young,Han, Seung Min,Jang, Ji-Hyun The Royal Society of Chemistry 2017 Chemical communications Vol.53 No.58

<▼1><P>This is the first report on the fabrication of defect-free submicron structures with more than 100 μm thickness and an aspect ratio over 100.</P></▼1><▼2><P>This is the first report on the fabrication of defect-free submicron structures with more than 100 μm thickness and an aspect ratio over 100. Highly transparent poly(glycidyl methacrylate-<I>co</I>-acryloisobutyl POSS) (PGP) was synthesized <I>via</I> radical polymerization. The mechanical properties of the PGP submicron structure displayed a Young's modulus of 6.09 GPa and a hardness of 0.16 GPa, 4.2 and 8 times, respectively, than those of SU8 nanopatterns. These enhancements enable the utilization of ultrathick 2D-/3D-submicron structures as an ideal platform for microelectromechanical systems, big data storage systems, energy devices, <I>etc.</I></P></▼2>

치과 기공사들에게서 나타나는 호흡기 증상과 이의 관련 요인

김웅철,오세윤,김지환,김진완,이준석,이가영,이세훈,유진호,김태석 高麗大學校 倂設 保健大學 保健科學硏究所 2001 保健科學論集 Vol.27 No.1

This study was carried out to investigate subjective respiratory symptoms and their attributable factors in Korean dental laboratory technicians. A questionnaire was mailed to randomly selected 1,900 dental laboratory technicians. Among them, 1,344 dental technicians completed the questionnaires and returmned them. Validity and reliability tests on the questionnaires were carried out before the main survey. To investigate risk factors on respiratory subjective symptoms, we performed analysis on distribution of characteristics, and then investigated univariate analysis and multiple logistic regression analysis. The prevalence rate of wheezing, cough and phlegm, and dyspnea was 4.8%, 33.9%, 54.9%, respectively. Statistically significant factors inducing subjective respiratory symptoms by multiple logistic regression analysis were sex, smoking, exercise, health examination, work hours a day, investment gas, investment dust, metal fume, resin vapor, and asbestos dust. Considering the results above, it seems that most subjective respiratory symptoms are related with health habits and occupational environmental-related factors. The result, consideration in mind, suggest that health promotion programs for smoking cessation, regular health examination, and physical exercise in health habit, and improvement on casting and resin work in dental technological environment be necessary.

A simple and robust route toward flexible CIGS photovoltaic devices on polymer substrates: Atomic level microstructural analysis and local opto-electronic investigation

Kim, Kihwan,Kim, Juran,Gang, Myeng Gil,Kim, Se-Ho,Song, Soomin,Cho, Yunae,Shin, Donghyeop,Eo, Young-Joo,Jeong, Inyoung,Ahn, Seung Kyu,Cho, Ara,Kim, Jayeong,Yoon, Seokhyun,Choi, Pyuck-Pa,Jo, William,Ki Elsevier 2019 Solar energy materials and solar cells Vol.195 No.-

<P><B>Abstract</B></P> <P>In this work, copper indium gallium selenide (Cu(In,Ga)Se<SUB>2</SUB>; CIGS) absorbers were grown on polyimide (PI)/molybdenum substrates by a three-stage co-evaporation process at various temperatures, film formation was systemically studied using various advanced characterization methods such as transmission electron microscopy, micro-Raman spectroscopy, Kelvin probe force microscopy, and atom probe tomography. The CIGS films on PI were found to exhibit considerable physical and electrical variations with respect to the process temperature of three-stage co-evaporation. In particular, when the process temperature reached 400 °C, the CIGS absorber on PI began to exhibit controlled microstructure and intergrain properties. By adjusting the microstructure and intergrain properties of the absorber films by means of the process temperature of three-stage co-evaporation, flexible CIGS solar cells on PI with an efficiency of 16.7% (with anti-refection coating) were achieved.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CIGS absorber films were grown on flexible polyimide/molybdenum substrates. </LI> <LI> Low-temperature three-stage process (≤440 °C) with extrinsic Na addition was used to CIGS growth. </LI> <LI> CIGS film evolution was systemically observed using advanced material characterization techniques. </LI> <LI> Highly efficient CIGS cells on flexible polyimide substrates were realized while maintaining process manufacturability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

성인에서 장기간 Furosemide오용과 연관된 신수질 석회화

김윤구,이윤하,이규백,장세호,김대중,오하영,김보현,김미경,조윤숙 대한신장학회 1996 대한신장학회잡지 Vol.15 No.4

수평 매복된 상악 중절치의 교정적 견인 : 증례 보고

김미니,김영재,김정욱,장기택,김종철,한세현,이상훈 大韓小兒齒科學會 2008 大韓小兒齒科學會誌 Vol.35 No.4

본 증례는 수평 변위 매복과 치근 만곡을 가진 상악 중절치를 폐쇄 노출법을 이용한 교정적 견인을 시행하여 영구 전치의 기능과 심미성을 회복하였다. 상악 영구 전치가 수평으로 매복된 경우,가급적 조기에 발견하는 것이 중요하며, 촉진,시진,방사선 사진 등을 이용한 적절한 치료 계획의 수립이 필요하다. 상악 영구 전치의 매복이 조기에 적절히 치료되지 못하면 정중선의 변위,인접치의 이동에 의한 맹출 공간의 감소,치조골 높이의 차이 뿐만 아니라,이로 인한 심미적인 문제를 야기하여 소아 심리 발달에 해로운 영향을 줄 수 있기 때문이다. 매복치의 치료는 매복치의 형태,위치,상태에 따라 다양하나,주기적 관찰 방법,상부 연조직과 경조직을 단순히 제거하여 맹출을 유도하는 방법,외과적 노출 후 매복치를 교정적으로 견인하는 방법,치아 이식술,발치 등을 시행할 수 있다. 이중 이번 증례에서 시행한 매복치의 교정적 견인은 매복치의 치축이 정상 맹출로와 일치되지 않으며,주기적인 관찰 후 더 이상의 맹출이 기대되지 않을 때 시행하는 가장 일반적으로 적용되는 방법으로 매복의 심도,치아의 발육단계,만곡의 부위와 정도,수술방법과 견인방향 등을 고려하여 치료의 예후를 향상 시킬 수 있다. Maxillary central incisor impactions occur infrequently. Their origins include various local causes, such as odontoma, supernumerary teeth, space loss, and disturbances in the eruption path, also trauma and apical follicular cysts. Impacted teeth can cause serious dental and aesthetic difficulties as well as psychological problems especially in anterior regions. Although the impaction of maxillary incisor occurs less frequently than that of the maxillary canine. it is of concern to parents during the early mixed dentition stage because of the uneruption of the tooth. Forced eruption of impacted teeth should be considered in young patients because this technique can lead to suitable results from a periodontal, occlusal, and esthetic perspective at an earlier stage better than with other treatment options. This report presents the surgical and orthodontic treatment of cases with horizontally impacted and dilacerated maxillary central incisors. For each patient. we used the closed eruption method. placed an attachment on the impacted tooth on surgery, and fully closed the flap. Traction was applied immediately. The impacted tooth erupts through the healed tissue in a manner resembling normal eruption.

Interface Shear Strength at Joints of Ultra‑High Performance Concrete Structures

Young?Jin Kim,Won?Jong Chin,Se?Jin Jeon 한국콘크리트학회 2018 International Journal of Concrete Structures and M Vol.12 No.6

When ultra-high performance concrete (UHPC) is fabricated as precast members such as in a UHPC segmental bridge, the joint design between the precast members can significantly affect the overall integrity and safety of the structure. Therefore, the structural behavior of the UHPC joint was experimentally investigated in this study with test variables including joint type, number and height of shear keys, type of filler, curing temperature, and lateral compressive stress. The UHPC considered in this study is the K-UHPC developed in Korea with a specified compressive strength as high as 180 MPa and high flowability. The joint shear strengths affected by the test variables were investigated in detail. The test results were also compared with two representative predictive equations for interface shear strength to determine an appropriate equation for the joint design of UHPC. These equations did not match well with the test data because they were originally proposed for normal strength concrete. However, the JSCE equation could be improved by modifying a coefficient to show good agreement with the test especially in the case of the dry joint with epoxy application.

A LONG-TERM FIELD TEST OF A LARGE VOLUME IONIZATION CHAMBER BASED AREA RADIATION MONITORING SYSTEM DEVELOPED AT KAERI

Kim, Han-Soo,Ha, Jang-Ho,Park, Se-Hwan,Kim, Jung-Bok,Kim, Young-Kyun,Jin, Hyung-Ho The Korean Association for Radiation Protection 2009 방사선방어학회지 Vol.34 No.2

An Area Radiation Monitoring System (ARMS) ionization chamber, which had an 11.8 L active volume, was fabricated and performance-tested at KAERI. Low leakage currents, linearities at low and high dose rates were achieved from performance tests. The correlation coefficients between the ionization currents and the dose rates are 1 at high dose rate and 0.99 at low dose rate. In this study, an integration-type ARMS ionization chamber was tested over a year for an evaluation of its long-term stability at a radioisotope (RI) repository of the Young-gwang nuclear power plant. The standard deviation of dose rate of 1 day data and over a 100-days mean value were 6.2 $\mu$R/h and 2.9 $\mu$R/h, respectively. The fabricated ARMS ionization chamber showed stable performance from the results of the long-term tests. Design and performance characteristics of the fabricated ionization chamber for the ARMS from performance-tests are also addressed.

도플러지수를 이용한 급성 심근경색증의 진단에 있어 노인 환자의 특징

김원,조규종,오세현,이영수,이은주,홍진숙,김영득,현석천,임경수 대한노인병학회 2000 Annals of geriatric medicine and research Vol.4 No.4

성인의 장중첩증에서 복부전산화단층촬영술의 유용성

김세웅,조영업,고영배,김원곤,김경국,김경래,우제홍,김미영 대한대장항문학회 1998 Annals of Coloproctolgy Vol.14 No.3