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).

The Effect of Topiramate on Hippocampal Neuronal Death and Expression of Glutamate Receptor in Kainate-induced Status Epilepticus Model

박민정,하세운,배혜란,김상호,Park Min-Jeong,Ha Se-Un,Bae Hae-Rahn,Kim Sang-Ho Korean Society of Life Science 2005 생명과학회지 Vol.15 No.3

신경흥분독성과 간질발작발현은 glutamate 수용체활성과 연관이 있다고 알려져 있다. a-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA), kainate 수용체에 대한 glutamate 활성을 포함하는 다양한 기전을 가진 항전간제인 Topiramate는 신경보호작용을 가진다는 증거가 제시되어 Topiramate가 간질발작 후 해마의 glutamate 수용체 발현에 미치는 효과를 관찰하였다. 흰쥐에 kainate를 복강 내 주사하여 간질중첩증을 유발시킨 후 Topiramate를 1주일 주사하였다 Apop tag in situ detection kit를 이용하여 세포손상을 관찰한 결과 kainate 유발 간질중첩증 1주일 후 해마의 CA1, CA3에서 심각한 세포사를 보였으나, Topiramte 처리 군에서는 세포사가 현저히 감소하였다. 간질중첩증 이후 NMDA 수용체 아형 1,2a, 2b 발현이 현저히 증가했으나 Topiramate 처치에 의해 NMDA수용체의 발현에는 뚜렷한 변화가 없었다. AMPA수용체에서는 GluR1이 간질중첩증 이후 현저히 상향 조정되었고 GluR2는 현저히 하향조정 되었다 Topiramate 1주일 처리 시 간질중첩증으로 인해 변화된 CluR1과 GluR2의 발현이 역전되었다. 결론적으로 Topiramate는 간질중침증에 의한 CluR1/CluR2 발현비의 증가로 유발되는 흥분성 신경세포사를 억제시킴으로써 신경보호작용이 있는 것으로 보인다. Excitotoxicity and epileptogenesis have often been associated with glutamate receptor activation. Accumulating evidences indicates that topiramate (TPM), an antiepileptic drug with multiple mechanisms of action has neuroprotective activity. We explored the neuroprotective effect of TPM on the status epilepticus (SE)-induced hippocampal neuronal death. After development of SE by kainite injection (15 mg/Kg), rats were treated with TPM (10mg/kg) for 1 week. The neuronal death was detected by Apop tag in situ detection kit, and the expression levels of glutamate receptors were semi-quantitatively analyzed by immunoblot. Kainate-induced SE caused a significant neuronal death and cell loss in CAI and CA3 regions of hippocampus at 1 week. However, treatment of TPM for 1 week after SE markedly reduced hippocampal neuronal death. The expression of N-methyl-D-aspartate (NMDA) receptor subunit 1, was increased by SE, but was not affected by 1 week treatment of TPM. The expressions of NMDA receptor subunit 2a and 2b were not changed by either SE or TPM. As for ${\alpha}-amino-3-hydroxy-5-methyl-4-isoxazole-propionate$ (AMPA) glutamate receptors (GluR), kainate-induced SE markedly up-regulated GluR1 expression but down-regulated GluR2 expression, leading to increased formation of $Ca^{2+}$ permeable GluR2- lacking AMPA receptors. TPM administration for 1 week attenuated SE-induced expression of both the up-regulation of GluR1 and down-regulation of GluR2, reversing the ratio of GluR1/GluR2 to the control value. In conclusion, TPM protects neuronal cell death against glutamate induced excitotoxicity in kainate-induced SE model, supporting the potential of TPM as a neuroprotective agent.

Electrical, Thermal, and Thermoelectric Transport Properties of Se-doped Polycrystalline Re2Te5

Se Woong Lee,Okmin Park,Hyun-Sik Kim,Won-Seon Seo,Sang-il Kim 대한금속·재료학회 2022 대한금속·재료학회지 Vol.60 No.12

Re2Te5 is considered a potential thermoelectric material because of its intrinsically low thermalconductivity, due to its complex crystal structure. Herein, a series of Se-doped Re2Te5 (Re2Te5-xSex, x = 0, 0.2,1, and 2) samples were synthesized, and their electrical and thermal transport properties were investigated. Pure orthorhombic Re2Te5 phases were successfully synthesized without any impurities for all compositions,and the continuous decrease in the calculated lattice parameters confirmed the substitution of Se atoms atthe Te sites. A maximum power factor of 0.135 mW/mK2was achieved for the sample with x = 0.2 at 880 K,mainly due to the increase in carrier concentration and electrical conductivity. The lattice thermalconductivity significantly decreased for all doped samples, which was attributed to the point defect phononscattering caused by Se doping. The thermoelectric figure of merit, zT reached a maximum value of 0.20 at880 K for Re2Te4.8Se0.2 (x = 0.2) sample, which was approximately 22% higher than that of the pristine Re2Te5sample. The weighted mobility, quality factor, and expected zT were calculated to evaluate the optimizationof the power factor and zT.

사상체질론의 정신의학적 타당성에 대한 연구

민성길,김동기,박진균,전세일 大韓神經精神醫學會 2001 신경정신의학 Vol.40 No.3

연구목적 : 건간한 의대상 312명과 신경증적 장애를 가진 환자 288명을 대상으로 하였다. 사상체질의 구별은 노정우 및 김달래 두 전문가에 의한 판정, 그리고 경희의대 사상체질 설문지(QSCC Ⅱ)에 의한 판정 등 3가지 방법에 의하였다. 연구 대상에게 정신과적 증상척도(SCL-90), 체질특성척도 및 성격척도를 사용하여 자가 평가하게 하였다. 각종 척도들의 타당도와 신뢰도는 입증되었다. 이 척도들을 통계적으로 분석하고 고전적 설명과 어느 정도 일치하는 지를 검토하였다. 연구결과 : 1) 3가지 분류방법간에 차이가 컸었다. 그 중 전문가의 직접적 면담에 의한 감별보다 QSCCⅡ 설문지형이 비교적 감별력이 컸다. 3) QSCCⅡ가 감별력이 비교적 크다고 하더라도 그 결과가 소음군의 대인공포-강박증, 불면-식용상실, 무력-예민-소화기-한기-피부증후군 그리고 정력부족등 신경증적 증상과 소극-비사교적, 내향형 성격 및 이성적 성격특징 등 몇가지 특징을 감별하는 데에만 비교적 유의하였고, 태음군의 특정인 독특한 신념, 온기, 활달-사교적 성격에 대해서는 부분적으로 그 특징을 감별하였다. 또한 소양군의 활달-사교형 성격과 감정형 성격의 특징 등은 극히 부분적으로 감별하였다. 결 론 : 이러한 결과는 현존하는 사상체질 구분방법에 일치점이 결여되어 있다는 것, 각종척도를 사용한 결과는 사상체질에 관한 고전적 설명을 부분적으로만 입증하고 있다는 것, 따라서 사상체질구분에 대한 향후보다 객관적인 연구가 필요하다는 것을 시사한다. Object : This study is to examine the validity of constitutional classification of Sa-sang medical theory. This theory classifies the human constitution to 4 types according to classical oriental philosophy on yin and yang. Subjects and Method : Subjects were 312 medical students and 288 neurotic patients with diagnosis of neurotic, stress related and somatoform disorders and minor depressive episodes according to ICD-10. Medical students were classified to 4 Sa-sang Constitution Classification(QSCCⅡ). For assessmnent of symptoms and signs, Korean version of SCL-90, a constitution scale and personality scale which were designed for this study were used. These instruments were found to be reliable and valid through statistical analysis. Subjects were asked to rate these scales. The data were analysed with factor analysis and factor scores were compared among 4 Sa-sang constitutions by ANOVA and t-test. The data from patient group were analysed with factor analysis and the results were compared with the Sa-sang medical theory. Results : Results of classification by 3 ways were inconsistent showing a significant difference among them. Among them, QSCCⅡ was most reliable. In QSCC Ⅱ, only the factor scores of factors of homophobia-obsession, weakness-sensitiveness-indigestion-chillness-skin syndrome, sexual weakness, passive-unsociable personality, introverted personality and rational, personality, were significantly high in So-um (small yin) group of medical students. A factor of warmnes and active-sociable personality were significantly high in Tae-um(big yin)group. Also active-sociable and effective pesonality was partly related with So-yang(small yang)group. Conclusion : These results suggest that those present classification methods inconsistent, that these methods are proving only parts of Sa-sang medical theory, and that objective and scientific studies are needed for reliability and validity of Sa-sang medical theory.

Chalcogenization-Derived Band Gap Grading in Solution-Processed CuIn_<i>x</i>Ga_1–<i>x</i>(Se,S)₂ Thin-Film Solar Cells

Park, Se Jin,Jeon, Hyo Sang,Cho, Jin Woo,Hwang, Yun Jeong,Park, Kyung Su,Shim, Hyeong Seop,Song, Jae Kyu,Cho, Yunae,Kim, Dong-Wook,Kim, Jihyun,Min, Byoung Koun American Chemical Society 2015 ACS APPLIED MATERIALS & INTERFACES Vol.7 No.49

<P>Significant enhancement of solution-processed CuInxGa1-x(Se,S)(2) (CIGSSe) thin-film solar cell performance was achieved by inducing a band gap gradient in the film thickness, which was triggered by the chalcogenization process. Specifically, after the preparation of an amorphous mixed oxide film of Cu, In, and Ga by a simple paste coating method chalcogenization under Se vapor, along with the flow of dilute H2S gas, resulted in the formation of CIGSSe films with graded composition distribution: S-rich top, In- and Se-rich middle, and Ga- and S-rich bottom. This uneven compositional distribution was confirmed to lead to a band gap gradient in the film, which may also be responsible for enhancement in the open circuit voltage and reduction in photocurrent loss, thus increasing the overall efficiency. The highest power conversion efficiency of 11.7% was achieved with J(sc) of 28.3 mA/cm(2), V-oc of 601 mV, and FF of 68.6%.</P>

Effects of substrate temperature on the performance of Cu₂ZnSnSe₄ thin film solar cells fabricated by co-evaporation technique

정성훈(Jung, Sung-Hun),안세진(Ahn, Se-Jin),윤재호(Yun, Jae-Ho),곽지혜(Gwak, Ji-Hye),조아라(Cho, A-Ra),윤경훈(Yoon, Kyung-Hoon),김동환(Kim, Dong-Hwan) 한국신재생에너지학회 2009 한국신재생에너지학회 학술대회논문집 Vol.2009 No.11

Despite the success of Cu(In,Ga)Se₂ (CIGS) based PV technology now emerging in several industrial initiatives, concerns about the cost of In and Ga are often expressed. It is believed that the cost of those elements will eventually limit the cost reduction of this technology. One candidate to replace CIGS is Cu₂ZnSnSe₄ (CZTSe), fabricated by co-evaporation technique. Co-evaporation technique will be one of the best methods to control film composition. This type of absorber derives from the CuInSe² chalcopyrite structure by substituting half of the indium atoms with zinc and other half with tin. Energy bandgap of this material has been reported to range from 0.8eV for selenide to 1.5eV for the sulfide and large coefficient in the order of 10^{14}cm^{-1}, which means large possibility of commercial production of the most suitable absorber by using the CZTSe film. In this work, Effects of substrate temperature of Cu₂ZnSnSe₄ absorber layer on the performance of thin films solar cells were investigated. We reported on some of the absorber properties and device results.

동시진공 증발법을 이용한 Cu₂ZnSnSe₄ 박막 태양전지의 제조와 기판온도가 광전압 특성에 미치는 영향

정성훈(Jung, Sung-Hun),안세진(Ahn, Se-Jin),윤재호(Yun, Jae-Ho),곽지혜(Gwak, Ji-Hye),김동환(Kim, Dong-Hwan),윤경훈(Yoon, Kyung-Hoon) 한국신재생에너지학회 2009 한국신재생에너지학회 학술대회논문집 Vol.2009 No.06

Despite the success of Cu(In,Ga)Se₂ (CIGS) based PV technology now emerging in several industrial initiatives, concerns about the cost of In and Ga are often expressed. It is believed that the cost of those elements will eventually limit the cost reduction of this technology. one candidate to replace CIGS is Cu₂ZnSnSe₄ (CZTSe), fabricated by co-evaporation technique. Effects of substrate temperature of Cu₂ZnSnSe₄ absorber layer on the performance of thin films solar cells were investigated. As substrate temperature increased, the grain size of Cu₂ZnSnSe₄ films increased presumably. At a optimal condition of substrate temperature is 320?C, the solar cell shows a conversion efficiency of 1.79% with V_{OC} of 0.213V, JSC of 16.91mA/cm² and FF of 49.7%.

성균관대학교 물리학과 방음실의 설계 및 제작

朴興秀,尹錫旺,李聖壽,朴光俊,吳世珍 성균관대학교 기초과학연구소 1986 論文集 Vol.37 No.1

An anechoic chamber was constructed to make to condition of acoustic free field at the Department of Physics, Sung Kyun Kwan University. In this paper the criteria for the design and construction of the anechoic chamber are described. 48cm long wedges of density 15.3kg/㎥ glasswool attached to the 40×20×20㎤ base were used for the lining of anechoic chamber with the cutoff frequency of 125Hz. The interior space of the chamber is 3.56m long, 3.38m wide and 2.37m high.

상아질 접착에서 collagenase와 esterase가 미세인장결합강도에 미치는 영향

정영정,현홍근,김영재,김정욱,이상훈,김종철,한세현,장기택 대한소아치과학회 2007 大韓小兒齒科學會誌 Vol.34 No.2

상아질-레진 접착강도에 대한 collagenase와 esterase의 영향을 살펴보기 위해, 소구치의 교합면 상아질에 Single Bond 2와 Clearfil SE Bond로 접착을 시행하고 미세 시편을 제작하여 PBS, collagenase 용액, esterase 용액에 4주간 보관한 후 미세인장결합강도를 측정, 비교하여 다음과 같은 결론을 얻었다. 1. 모든 보관 용액에서 Single Bond 2의 미세인장결합강도는 Clearfil SE Bond보다 유의하게 낮았다(p<0.05). 2. Single Bond 2의 미세인장결합강도는 collagenase군이 PBS군, esterase군보다 낮았다(p>0.05). 3. Clearfil SE Bond의 미세인장결합강도는 esterase군이 PBS군에 비해 낮았으나(p>0.05), collagenase군보다는 높았다(p>0.05). Collagenase군은 PBS군에 비해 유의하게 낮은 미세인장결합강도를 보였다(p<0.05). The purpose of this study was to evaluate the effect of collagenase and esterase on the microtensile bond strength (μTBS) in dentin bonding. After resin composites were bonded to occlusal dentin, μTBS specimens were formed and stored in PBS, collagenase, or esterase solution. After 4-week storage, μTBS was determined and, the results were as follows: 1. μTBS values of Single Bond 2 were lower than those of Clearfil SE Bond for all storage medium (p<0.05). 2. In single Bond 2 group, collagenase solution lowered bond strength more than PBS and esterase solution (p>0.05). 3. In Clearfil SE Bond group, esterase solution lowered bond strength more than PBS(p>0.05). Collagenase solution lowered bond strength more than esterase solution(p>0.05) and PBS(p<0.05).

적혈구 유무에 따른 벤젠, 스티렌, 트리클로로에틸렌에 의한 림프구 중 자매염색분체 교환 빈도

성재혁,김형아,신민정,최미정,이세훈 가톨릭대학교 산업의학센터 2001 韓國의 産業醫學 Vol.40 No.4

This study was performed to investigate the possible role of oxyhemoglobin in the metabolic activation of benzene, styrene and TCE by observing the difference of the SCE frequency between isolated lymphocyte and whole blood lymphocyte cultures exposed to these chemicals. Isolated lymphocyte and fresh heparinized peripheral whole blood samples from a healthy donor(male, smoker) were cultured in the phytohaemagglutinin stimulated culture media for 72 hours. The cells were treated with 100, 300, 1000, 3000 μM benzene, 250, 500, 100, 2000 μM styrene or TCE respectively. Slides were stained with Giemsa's solution for SCE. SCE was analyzed for each subject from coded slides by one researcher. The results were as follows : 1.The frequency of SCE increased dose-dependently with concentration of benzene in isolated lymphocyte and whole blood lymphocyte cultures, however there were no significance. There was no significant difference of SCE frequency between isolated lymphocyte and whole blood lymphocyte cultures. 2.The frequency of SCE in whole blood exposed to sytrene significantly increased in dose-dependant relationship, but not in isolated lymphocyte. The difference of SCE frequency between isolated lymphocyte and whole blood lymphocyte of 2000μM styrene exposure was marginally significant(P=0.0540). 3.In TCE, the frequency of SCE did not increase at any concentration used in this study of isolated lymphocyte and whole blood lymphocyte. Above results suggested that oxyhemoglobin in erythrocytes play an important role in the metabolic activation of styrene but not in benzene or TCE. Key Words : Benzene, Styrene, Trichloroethylene, Sister chromatid exchange, Metabolic activation, Oxyhemoglobin