• 제목/요약/키워드: alpha-dual

검색결과 140건 처리시간 0.028초

중간레진의 친수성이 상아질 접착에 미치는 영향 (EFFECT OF INTERMEDIATE RESIN HYDROPHILICITY ON BOND STRENGTH OF SINGLE STEP ADHESIVE)

  • 김용성;박상혁;최기운;최경규
    • Restorative Dentistry and Endodontics
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    • 제32권5호
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    • pp.445-458
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    • 2007
  • 단일과정 접착제를 이용함에 있어 복합레진과의 부적합성을 개선하고자 중간레진이 결합에 영향을 미칠 것으로 사료된다. Experimental single step system (Bisco Ltd., Schaumburg, IL)을 대조군으로 하고 6종의 중간레진을 접착제의 중합여부, 복합레진의 광중합-자가중합 여부로 분류하였다. 상아질에 대한 광중합 또는 자가중합형 복합레진의 결합강도를 측정하고 접착계면에 대한 투과전자현미경 관찰하여 다음과 같은 결론을 얻었다. 1. 중간레진의 적용은 광중합형 복합레진의 결합강도를 증가시키지 않았다. 2. 자가중합형 복합레진의 결합강도는 중간레진을 적용할 경우 증가하였다. 3. 중간레진의 적용 전 접착제의 중합여부는 결합강도의 변화에 영향을 미치지 않았다. 4. 중간레진이 친수성일 때 소수성 중간레진을 적용할 때 보다 높은 결합강도를 나타냈으나 통계적 유의차는 없었다. 광중합형 복합레진의 수복 시 단일과정 접착제를 사용하는 것은 초기 결합강도에 영향을 미치지 않으며, 자가중합형 복합레진을 단일과정 접착제와 사용할 때는 접착층의 투과도를 감소시키는 소수성의 중간레진을 적용하여 부적합성을 해소할 수 있을 것이다.

유자녀 맞벌이 부부의 일-가족 전이과정과 전이발생영역 (The Differences in Work-family Spillover Process and Domains in Dual-earner Couples with Children)

  • 장윤옥;정서린
    • 가정과삶의질연구
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    • 제32권5호
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    • pp.145-161
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    • 2014
  • The purpose of this study examined the differences in work-family spillover process and domains in dual-earner couples with children, using a multidimensional measure of work-family spillover. The subjects of this study were 285 working couples with children. The research tool was questionnaires which consisted of general characteristics of the subjects and multidimensional measure of work-family spillover scale. For data analysis, factor analysis, Cronbach ${\alpha}$, t-test, and paired t-test were performed. Based on analysis of data using factor analysis, three-distinct work-family spillover process can be measured for both wife and husband, time interference, psychological distraction, and energy depletion and the multidimensional measure of work-family spillover is able to validly assess different domains of family life into which spillover occurs. The main results of this study were as following: First, there were significant differences in work-family spillover process according to sex. In work${\rightarrow}$family spillover, male more experienced negative time interference than female, on the other hand, in family${\rightarrow}$work spillover, female more experienced negative energy depletion than male. Second, there were significant differences in domains which work-family spillover occurs according to sex. Male more experienced negative work${\rightarrow}$family spillover than female in marital relations and parent-child relations domains while female more experienced negative family${\rightarrow}$work spillover than male in parent-child relations and home management domains. Third, there were significant differences between wife and husband in work-family spillover process. In work${\rightarrow}$family spillover, husband more experienced negative time interference than wife, on the other hand, in family${\rightarrow}$work spillover, wife more experienced negative energy depletion than husbands. Forth, there were significant differences between wife and husband in domains which work-family spillover occurs. Male more experienced negative work${\rightarrow}$family spillover than female in marital relations, parent-child relations, and leisure life domains. And while husband more experienced negative family${\rightarrow}$work spillover than wife in parent-child relations, wife more experienced negative family${\rightarrow}$work spillover than husband in home management domains.

밀양소분지 건천리 일원의 백악기 암석에 대한 고자기 연구 (Palaeomgnetic Study on the Cretaceous Rocks in the Konchonri Area of the Northern Milyang Subbasin, Korea)

  • 강희철;김인수;윤성효
    • 지구물리
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    • 제3권1호
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    • pp.1-12
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    • 2000
  • 경상분지내 밀양소분지의 건천리 지역에 분포하는 백악기 하양층군의 송내동층, 채약산화산암, 건천리층, 그러고 유천층군 하부인 주사산안산암을 대상으로 지층생성 당시의 자북의 위치와 퇴적시기를 결정하기 위하여 12개 노두에서 106개의 정향시료 채취하여 고자기 연구를 수행하였다. 연구결과 주 자성광물인 적철석과 자철석에 의하여 기록된 이들 지층들의 평균 특성잔류자기 방향은 역전검사 그리고 통계학적으로 99%의 신뢰도를 가지며 습곡검사 통과하였다. 단계적 습곡검사에서는 군집지수 k값의 변화가 90%의 지층경사보정 단계에서 최대를 보여서 이들 지층들의 특성잔류 자기는 지층경사나 습곡작용 이전 즉, 퇴적 동시기이거나 그 직후에 획득된 1차 잔류자기임을 지시한다. 이들의 평균 방향과 고자기극의 위치는 각자 $D=22.9^{\circ},\;I=59.1^{\circ}\;(k=410,\;{\alpha}_{95}=3.0^{\circ},\;N=7sites)$$199.6^{\circ}E,\;71.6^{\circ}N\;(K=206.9,\;A_{95}=4.2^{\circ})$이다. 이는 중국대륙 및 경상분지내 다른 동시대 지층들에서 구한 방향들과 오차한계 내에서 동일한 것으로서 연구지역과 이들 지역간에 상대적 변위나 수평회전운동이 거의 없었음을 지시한다. 자기층서학적 견지에서 볼 때, 연구지층들은 백악기 상부 알비안(upper Albian)에서 하부 캄파니안(lower Campanian)의 역자극기까지의 것으로 대비된다. 한편, 채약산화산암과 주사산안산암의 응회암과 및 각력암에서는 분산된 특성잔류자기 방향이 나타났는데 이는 암석들이 잔류자기를 획득한 후에 화산함몰 구조운동에 의하여 재동(reworked)되었음을 의미한다.

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주정증류 폐기물의 당화 및 구연산 발효에 관한 연구(I) (Studies on Saccharification and Citric Acid Fermentation of Alcoholic Distillery Waste(I))

  • 서명교;서근학송승그
    • KSBB Journal
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    • 제5권4호
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    • pp.383-390
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    • 1990
  • 주정공장에서 배출되는 쌀보리 주정증류 폐기물을 효소와 산으로 가수분해하여 구연산 발효를 행한 결과를 요약하면 다음과 같다. 폐기물을 농축하여 당의 농도를 50g / l로 하였을때 글루코오즈, 구연산 및 균체농도는 각각 5.7g / l, 0.8g / l 및 3.86g / l가 얻어졌고 $\alpha$- 및 $\beta$-amylase에 의한 폐기물의 효소 가수분해에 의해서 글루코오즈, 구연산 및 균체농도가 각각 81g / l, 1g / l 및 5.33g / l가 얻어졌으며 25% 염산에 의한 산가수분해에 의해서는 각각 21.5g / l, 1.75g / l 및 4.9g / l가 얻어졌다. 10시간동안 계속된 2차 산 가수분해를 행한 결과 글루코오즈의 농도가 3.44g / l로 장기간의 산 가수분해는 생성된 글루코오즈를 분해시키는 속도가 3당류 이상의 올리고 환원당의 분해속도보다 빨랐다. 폐기물내 균체 접종량을 0.5%에서 2%로 증가시킴에 따라 균체농도는 1.35g / l에서 3.71g / l 로 증가 하였으나 구연산 농도는 0.4g / l에서 0.12g / l로 감소하였으며 또한 질산암모늄을 3g / l를 첨가할 경우 균체 농도는 3.7g / l에서 7.3g / l로 증가하였으나 구연산 농도는 0.12g / l에서 0.08g / l로 감소되었다. $MnSO_4{\cdot}4~5H_2O$의 농도가 0.0125g / l 일때 구연산 생산량이 가장 많았으나 농도가 증가함에 따라 구연산 생산이 감소하였으므로 금속이온이 과다하게 존재할때는 구연산 생산이 저해됨을 알았다.

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The effect of IDS (immediate dentin sealing) on dentin bond strength under various thermocycling periods

  • Lee, sungbok Richard;Lee, Sang-Min;Park, Su-Jung;Lee, Suk-Won;Lee, Do Yun;Im, Byung-Jin;Ahn, Su-Jin
    • The Journal of Advanced Prosthodontics
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    • 제7권3호
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    • pp.224-232
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    • 2015
  • PURPOSE. The purpose of this study was to find out the effect of immediate dentin sealing (IDS) on bond strength of ceramic restoration under various thermocycling periods with DBA (dentin bonding agent system). MATERIALS AND METHODS. Fifty freshly extracted human mandibular third molars were divided into 5 groups (1 control and 4 experimental groups) of 10 teeth. We removed enamel layer of sound teeth and embedded them which will proceed to be IDS, using All Bond II. A thermocycling was applied to experimental groups for 1, 2, 7, 14 days respectively and was not applied to control group. IPS Empress II for ceramic was acid-etched with ceramic etchant (9.5% HF) and silane was applied. Each ceramic disc was bonded to specimens with Duo-link, dual curable resin cement by means of light curing for 100 seconds. After the cementation procedures, shear bond strength measurement and SEM analysis of the fractured surface were done. The data were analyzed with a one-way ANOVA and Tukey multiple comparison test (${\alpha}$=.05). RESULTS. There were no statistically significant differences between 4 experimental groups and control group, however the mean value started to decrease in group 7d, and group 14d showed the lowest mean bond strength in all groups. Also, group 7d and 14d showed distinct exposed dentin and collapsed hybrid layer was observed in SEM analysis. CONCLUSION. In the present study, it can be concluded that ceramic restorations like a laminate veneer restoration should be bonded using resin cement within one week after IDS procedure.

Tapentadol: Can It Kill Two Birds with One Stone without Breaking Windows?

  • Chang, Eun Jung;Choi, Eun Ji;Kim, Kyung Hoon
    • The Korean Journal of Pain
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    • 제29권3호
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    • pp.153-157
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    • 2016
  • Tapentadol is a novel oral analgesic with a dual mode of action as an agonist of the ${\mu}$-opioid receptor (MOR), and as a norepinephrine reuptake inhibitor (NRI) all in a single molecule. Immediate release (IR) tapentadol shows its analgesic effect quickly, at around 30 minutes. Its MOR agonistic action produces acute nociceptive pain relief; its role as an NRI brings about chronic neuropathic pain relief. Absorption is rapid, with a mean maximal serum concentration at 1.25-1.5 h after oral intake. It is present primarily in the form of conjugated metabolites after glucuronidation, and excretes rapidly and completely via the kidneys. The most common adverse reactions are nausea, dizziness, vomiting, and somnolence. Constipation is more common in use of the ER formulation. Precautions against concomitant use of central nervous system depressants, including sedatives, hypnotics, tranquilizers, general anesthetics, phenothiazines, other opioids, and alcohol, or use of tapentadol within 14 days of the cessation of monoamine oxidase inhibitors, are advised. The safety and efficacy have not been established for use during pregnancy, labor, and delivery, or for nursing mothers, pediatric patients less than 18 years of age, and cases of severe renal impairment and severe hepatic impairment. The major concerns for tapentadol are abuse, addiction, seeking behavior, withdrawal, and physical dependence. The presumed problem for use of tapentadol is to control the ratio of MOR agonist and NRI. In conclusion, tapentadol produces both nociceptive and neuropathic pain relief, but with worries about abuse and dependence.

복합 유성 기어로 구성된 하이브리드 시스템 효율 분석 (Analysis of the Efficiency of the Compound-split Hybrid Systems)

  • 김남욱;양호림;조성태;박영일;차석원
    • 한국자동차공학회논문집
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    • 제15권5호
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    • pp.118-124
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    • 2007
  • The efficiency of the hybrid systems which are composed of compound planetary gear sets depend on the amount of the recirculating energy among the motors and battery. This paper studies the analysis of the system efficiency with the parameters, ${\alpha},\;{\beta},\;{\gamma_a},\;{\gamma_b}$ and $\gamma_s$. The efficiency of the systems and the relative torque, speed and power of the power resources are represented by these parameters. The recuperating parameter $\kappa$ which makes the systems generalized is introduced, so the efficiencies of the modes such as the hybrid mode, the engine mode, the motoring mode and the recuperating mode are analyzed with simple equations. The tendency of the system efficiency according to the variations of the $\gamma_s$ and $\kappa$ are studied, by which it can be possible to reduce the loss of the power because the strategies for avoiding the singular speed ratio $\gamma_s$ are helpful for the system efficiency and specific value of $\kappa$ can increase the efficiency of the systems.

Influence of abutment height and convergence angle on the retrievability of cement-retained implant prostheses with a lingual slot

  • Choi, Kyu-Hyung;Son, KeunBaDa;Lee, Du-Hyeong;Lee, Kyu-Bok
    • The Journal of Advanced Prosthodontics
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    • 제10권5호
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    • pp.381-387
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    • 2018
  • PURPOSE. Cement-retained implant prostheses can lack proper retrievability during repair, and residual cement can cause peri-implantitis. The purpose of this in vitro study was to evaluate the influence of abutment height and convergence angle on the retrievability of cement-retained implant prostheses with lingual slots, known as retrievable cement-type slots (RCS). MATERIALS AND METHODS. We fabricated six types of titanium abutments (10 of each type) with two different heights (4 mm and 6 mm), three different convergence angles ($8^{\circ}$, $10^{\circ}$, and $12^{\circ}$), a sloped shoulder margin (0.6 mm depth), a rectangular shape ($6mm{\times}6.5mm$) with rounded edges, and a rectangular ledge ($2mm{\times}1mm$) for the RCS. One monolithic zirconia crown was fabricated for each abutment using a dental computer-aided design/computer-aided manufacturing system. The abutments and crowns were permanently cemented together with dual-curing resin cement, followed by 24 hours in demineralized water at room temperature. Using a custom-made device with a slot driver and torque gauge, we recorded the torque ($N{\cdot}cm$) required to remove the crowns. Statistical analysis was conducted using multiple regression analysis and Mann-Whitney U tests (${\alpha}=.05$). RESULTS. Removal torques significantly decreased as convergence angles increased. Multiple regression analysis showed no significant interaction between the abutment height and the convergence angle (Durbin-Watson ratio: 2.186). CONCLUSION. Within the limitations of this in vitro study, we suggest that the retrievability of cement-retained implant prostheses with RCS can be maintained by adjusting the abutment height and convergence angle, even when they are permanently cemented together.

Anti-Inflammatory Activity of Compounds from the Whole Plant of Patrinia saniculaefolia

  • An, Ren-Bo;Na, Min-Kyun;Min, Byung-Sun;Chang, Hyeun-Wook;Bae, Ki-Hwan
    • Natural Product Sciences
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    • 제17권2호
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    • pp.90-94
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    • 2011
  • An in vitro bioassay-guide revealed that the methanol (MeOH) extract of the whole plant of Patrinia saniculaefolia (Valerianaceae) showed cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) dual inhibitory activity by assessing their effects on the production of prostaglandin $D_2$ ($PGD_2$) and leukotriene $C_4$ ($LTC_4$) in mouse bone marrow-derived mast cells (BMMCs). Phytochemical study of the MeOH extract of this plant led to the isolation of twelve compounds; ${\beta}$-farnesene (1), squalene (2), nardostachin (3), patridoid I (4), patridoid II (5), patridoid II-A (6), oleanolic acid (7), oleanonic acid (8), 23-hydroxyursolic acid (9), oleanolic acid 3-O-${\alpha}$-L-arabinopyranoside (10), oleanolic acid 3-O-${\beta}$-D-glucopyranoside (11), oleanolic acid 3-O-[${\beta}$-D-xylopyranosyl-(1${\rightarrow}$3)-${\beta}$-D-(6-O-butyl)glucuronopyranoside] (12). Among the compounds, 4 and 5 strongly inhibited both the COX-2-dependent $PGD_2$ generation with $IC_{50}$ values of 8.7 and 13.6 ${\mu}M$, respectively, and the generation of $LTC_4$ in the 5-LOX dependent phase with $IC_{50}$ values of 41.7 and 46.9 ${\mu}M$, respectively, which suggest that the anti-inflammatory activity of P. saniculaefolia might occur in part via the inhibition of both $PGD_2$ and $LTC_4$ generation by 4 and 5.

Influence of modification in core building procedure on fracture strength and failure patterns of premolars restored with fiber post and composite core

  • Kim, Young-Hoi;Lee, Jong-Hyuk
    • The Journal of Advanced Prosthodontics
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    • 제4권1호
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    • pp.37-42
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    • 2012
  • PURPOSE. The influence of the modified process in the fiber-reinforced post and resin core foundation treatment on the fracture resistance and failure pattern of premolar was tested in this study. MATERIALS AND METHODS. Thirty-six human mandibular premolars were divided into 4 groups (n = 9). In group DCT, the quartz fibre post (D.T. Light-post) was cemented with resin cement (DUO-LINK) and a core foundation was formed with composite resin (LIGHT-CORE). In group DMO and DMT, resin cement (DUO-LINK) was used for post (D.T. Lightpost) cementation and core foundation; in group DMO, these procedures were performed simultaneously in one step, while DMT group was accomplished in separated two steps. In group LCT, the glass fiber post (LuxaPost) cementation and core foundation was accomplished with composite resin (LuxaCore-Dual) in separated procedures. Tooth were prepared with 2 mm ferrule and restored with nickel-chromium crowns. A static loading test was carried out and loads were applied to the buccal surface of the buccal cusp at a 45 degree inclination to the long axis of the tooth until failure occurred. The data were analyzed with MANOVA (${\alpha}$= .05). The failure pattern was observed and classified as either favorable (allowing repair) or unfavorable (not allowing repair). RESULTS. The mean fracture strength was highest in group DCT followed in descending order by groups DMO, DMT, and LCT. However, there were no significant differences in fracture strength between the groups. A higher prevalence of favorable fractures was detected in group DMT but there were no significant differences between the groups. CONCLUSION. The change of post or core foundation method does not appear to influence the fracture strength and failure patterns.