• Title, Summary, Keyword: BIS

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Syntheses of New Nitrogen-Oxygen Multidentate Ligands and Their Stability Constants of Transition Metal(Ⅱ) Ions (새로운 질소-산소계 여러 자리 리간드의 합성 및 전이금속(Ⅱ)이온 착물의 안정도상수)

  • Kim, Sun Deuk;Jang, Ki Ho;Kim, Jun Kwang
    • Journal of the Korean Chemical Society
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    • v.42 no.5
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    • pp.539-548
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    • 1998
  • Multidentate N,O-containing ligands, such as N,N'-bis(2-hydroxybenzyl)-ethylenediamine(BHED), N,N'-bis(2-hydroxybenzyl)-propylenediamine(BHPD), N,N'-bis(2-hydroxybenzyl)-diethylenetriamine(BHDT), N,N'-bis(2-hydroxybenzyl)-triethylenetriamine(BHTT) and N,N'-bis(2-hydroxybenzyl)-tetraethylenepentaamine (BHTP) were synthesized by reduction of the imine group of Bis(salicylidene)-ethylendiamine(BSED), Bis (salicylidene)-propylenediamine(BSPD), Bis(salicylidene)-diethylentriamine(BSDT), Bis(salicylidene)-triethylenetetraamine(BSTT) and Bis(salicylidene)-tetraethylenepentaamine(BSTP). Proton dissociation constants of the ligands and stability constants of transition metal(Ⅱ) ion complexes with BHED, BHPD, BHDT, BHTT, and BHTP were determined by potentiometic titration. The sequence of stability constants $(logK_{ML})$ of complex increases as BHED Zn(Ⅱ) which follows the Irving-Williams series.

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Characteristics of Polymeric Dental Restorative Composites Fabricated from Bis-GMA Derivatives Having Low Viscosity (저점도 Bis-GMA 유도체로부터 제조된 고분자계 치과 수복용 복합재의 특성)

  • Jeon, Mi-Young;Song, Jeong-Oh;Kim, Chang-Keun
    • Polymer Korea
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    • v.31 no.6
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    • pp.491-496
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    • 2007
  • In the polymeric dental restorative composites, the resin matrix mainly contains 70 wt% 2,2-bis[4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane (Bis-GMA), as a base resin and 30 wt% triethylene glycol dimethacrylate (TEGDMA) as a diluent. Even though the viscosity of the resin matrix is rapidly decreased by adding TEGDMA, addition of TEGDMA to the Bis-GMA results in reduction in the mechanical properties and increase in the curing shrinkage of the dental composite. In order to fabricate dental composite exhibiting excellent properties by reducing TEGDMA content in the resin matrix, in this study, Bis-GMA derivatives, which do not contain hydroxyl groups, were used instead of Bis-GMA. The curing characteristics of Bis-GMA derivatives were similar with those of Bis-GMA, while the former exhibited lower viscosity and water absorption than the latter. Comparing the curing shrinkage of the dental composite containing Bis-GMA derivative with that prepared from Bis-GMA, the reduction in curing shrinkage was about 25%. Dental composites prepared from new resin matrices also exhibited low water uptake and better properties in mechanical strength.

Effect of BIS depletion on HSF1-dependent transcriptional activation in A549 non-small cell lung cancer cells

  • Yun, Hye Hyeon;Baek, Ji-Ye;Seo, Gwanwoo;Kim, Yong Sam;Ko, Jeong-Heon;Lee, Jeong-Hwa
    • The Korean Journal of Physiology and Pharmacology
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    • v.22 no.4
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    • pp.457-465
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    • 2018
  • The expression of BCL-2 interacting cell death suppressor (BIS), an anti-stress or anti-apoptotic protein, has been shown to be regulated at the transcriptional level by heat shock factor 1 (HSF1) upon various stresses. Recently, HSF1 was also shown to bind to BIS, but the significance of these protein-protein interactions on HSF1 activity has not been fully defined. In the present study, we observed that complete depletion of BIS using a CRISPR/Cas9 system in A549 non-small cell lung cancer did not affect the induction of heat shock protein (HSP) 70 and HSP27 mRNAs under various stress conditions such as heat shock, proteotoxic stress, and oxidative stress. The lack of a functional association of BIS with HSF1 activity was also demonstrated by transient downregulation of BIS by siRNA in A549 and U87 glioblastoma cells. Endogenous BIS mRNA levels were significantly suppressed in BIS knockout (KO) A549 cells compared to BIS wild type (WT) A549 cells at the constitutive and inducible levels. The promoter activities of BIS and HSP70 as well as the degradation rate of BIS mRNA were not influenced by depletion of BIS. In addition, the expression levels of the mutant BIS construct, in which 14 bp were deleted as in BIS-KO A549 cells, were not different from those of the WT BIS construct, indicating that mRNA stability was not the mechanism for autoregulation of BIS. Our results suggested that BIS was not required for HSF1 activity, but was required for its own expression, which involved an HSF1-independent pathway.

The effect of the strength and wetting characteristics of Bis-GMA/TEGDMA-based adhesives on the bond strength to dentin (2,2-Bis[4-(2-methoxy-3-methacryloyloxy propoxy) phenyl] propane을 함유한 상아질 접착레진의 물성이 접착강도에 미치는 영향)

  • Park, Eun-Sook;Kim, Chang-Keun;Bae, Ji-Hyun;Cho, Byeong-Hoon
    • Restorative Dentistry and Endodontics
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    • v.36 no.2
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    • pp.139-148
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    • 2011
  • Objectives: This study investigated the effect of the strength and wetting characteristics of adhesives on the bond strength to dentin. The experimental adhesives containing various ratios of hydrophobic, low-viscosity Bis-M-GMA, with Bis-GMA and TEGDMA, were made and evaluated on the mechanical properties and bond strength to dentin. Materials and Methods: Five experimental adhesives formulated with various Bis-GMA/Bis-MGMA/TEGDMA ratios were evaluated on their viscosity, degree of conversion (DC), flexural strength (FS), and microtensile bond strength (MTBS). The bonded interfaces were evaluated with SEM and the solubility parameter was calculated to understand the wetting characteristics of the adhesives. Results: Although there were no significant differences in the DC between the experimental adhesives at 48 hr after curing (p > 0.05), the experimental adhesives that did not contain Bis-GMA exhibited a lower FS than did those containing Bis-GMA (p < 0.05). The experimental adhesives that had very little to no TEGDMA showed significantly lower MTBS than did those containing a higher content of TEGDMA (p < 0.05). The formers exhibited gaps at the interface between the adhesive layer and the hybrid layer. The solubility parameter of TEGDMA approximated those of the components of the primed dentin, rather than Bis-GMA and Bis-M-GMA. Conclusions: To achieve a good dentin bond, a strong base monomer, such as Bis-GMA, cannot be completely replaced by Bis-M-GMA for maintaining mechanical strength. For compatible copolymerization between the adhesive and the primed dentin as well as dense cross-linking of the adhesive layer, at least 30% fraction of TEGDMA is also needed.

Mechanical properties of composite resins for dental restorative (치과 수복재용 복합레진의 기계적 물성에 대한 연구)

  • Ryu, Ho-Nam;Lee, Kwang-Rae
    • Journal of Industrial Technology
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    • v.35
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    • pp.31-34
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    • 2015
  • The purpose of the study was to investigate the mechanical properties (diametral tensile strength, flexural strength, compressive strength, Vickers hardness) of 4 kinds of composit resins; Bis-GMA based composit, Bis-EMA based composit, Bis-GMA/UDMA based composit, and Bis-EMA/UDMA based composit, The composit resin based Bis-GMA showed stronger mechanical properties than Bis-EMA. It was found that the addition of UDMA to both Bis-GMA based composit and Bis-EMA based composit highly improved mechanical properties. However, the mechanical properties of the composit resins prepared in this study were lower than those of the commercialized products in market(Charmfil flow(Denkist), Quadrant flow(CAVEX)), since the composit resins prepared in this study has much lower inorganic filler content of 43wt% comparing with 50~70wt% inorganic filler content of the commercialized products.

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The Study of Bus Information System's Efficiency (버스정보시스템의 효율성에 관한 연구)

  • Lee, Jeong-Keun;Choi, Suk-Woo;Hwang, Beyung-Ok
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.5 no.3
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    • pp.1-12
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    • 2006
  • Nowdays ITS is being installed in each local autonomous entity, and BIS installation and operation is prior to other ITS sub systems for the public service. The methods of positioning md wireless communication in BIS are DSRC+DSRC, GPS+wireless communication, Beacon+Beacon, which are chosen and operated as the local features. Before this study, the before and after survey of BIS' quality have only been done without performance evaluation of BIS. So the method of BIS' evaluation have been established including performance test in this paper. And the evaluation of some BIS' reliability and efficiency have been done using the reliability of arriving data and the wireless communication response rates after choosing typical BIS' sub system.

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Synthesis and Optical Characterization of 1,1-bis(trisilyl)tetraphenylsilole (1,1-Bis(trisilyl)tetraphenylsilole의 합성 및 광학적 특성)

  • Lee, Sung Gi;Kim, Bumseok
    • Journal of the Chosun Natural Science
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    • v.2 no.2
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    • pp.73-77
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    • 2009
  • Silyl-containing tetraphenylsilole, 1,1-bis(trisilyl)tetraphenylsilole, has been synthesized from the reaction of dichlorotetraphenylsilole and dichlorotrisilane and characterized by using NMR spectroscopy. Bis(trisilyl)tetraphenylsilole exhibits an unusual optical property and its optical property was characterized by UV-vis and fluorescence spectroscopy. Absorption wavelength maxima of bis(trisilyl)tetraphenylsilole was 380 nm. Bis(trisilyl)tetraphenylsilole displayed an emission band at 530 nm with an excitation wavelength of 380 nm.

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Synthesis and characterization of star-shaped imide compounds

  • Jeon, Eunju;Yoon, Tae-Ho
    • Rapid Communication in Photoscience
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    • v.1 no.1
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    • pp.19-20
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    • 2012
  • Novel star-shaped imide compounds containing electron-donating triphenylamine and/or electron-withdrawing bis(trifluoromethyl)phenyl side groups were synthesized via a two-step process. First, 3,6-dibromo-benzene-1,2,4,5-tetracarboxylic acid (2B4BA) was reacted with 4-aminophenyl (diphenylamine) (ATPA) or 3,5-bis(trifluoromethyl)aniline (6FA) by imide reaction. Then, Suzuki coupling reaction was carried out on these compounds with 4-(N,N-diphenylamino)-1-phenyl boronic acid (BTPA) or 3,5-bis(trifluoromethyl)phenyl boronic acid (6FBB), resulting in 3,6-bis[4-(diphenylamino)phenyl]-N,N'-bis[4-(diphenylamino) phenyl]-pyromellitimide (TPTPPI), 3,6-bis[3,5-bis(trifluoro methyl) phenyl]-N,N'-bis[3,5-bis(trifluoromethyl) phenyl]-pyro mellitimide (6F6FPI) or 3,6-bis[4-(diphenylamino)phenyl]-N,N'-bis[3,5-bistrifluoromethyl)phenyl]-pyromellitimide (6FTPPI). The imide compounds obtained were characterized by NMR, FT-IR, DSC, TGA, melting point analyzer, EA, and solubility measurements. In addition, their optical and electrical properties were evaluated by fluorescence spectroscopy, UV-vis spectroscopy, and cyclic voltammetry (CV). 6F6FPI exhibited deep blue emission (443 nm), along with high $T_m$ ($382^{\circ}C$) and relatively high $T_g$ ($148^{\circ}C$).

Synthesis of 1,4-Bis(1'-alkyl-2',3',4',5'-tetraphenyl-1'-silacyclopentadienyl)benzenes (1,4-Bis(silyl)benzene의 고리화반응에 의한 1,4-Bis(1'-alkyl-2',3',4',5'-tetraphenyl-1'-silacyclopentadienyl)benzenes 리간드의 합성)

  • Kong, Young Kun;Ahn, Young Man
    • Journal of the Korean Chemical Society
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    • v.41 no.2
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    • pp.82-87
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    • 1997
  • The 1,4-bis(alkyldichlorosilyl)benzene was synthesized to be a precursor of the bis(silacyclopentadienyl) aromatic system. The cyclization reaction of the precursor with 1,4-dilithio-1,2,3,4-tetraphenyl-1,3-butadiene produced the 1,4-bis(1'-alkyl-2',3',4',5'-tetraphenyl-1'-silacyclopentadienyl)benzene as the ligand of organotransition metal compound and the precursor of the stable silacyclopentadienyl anion.

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BIS Capital Adequacy Ratio Management by Mutual Savings Banks (상호저축은행의 BIS자기자본비율 조정 실태분석)

  • Kim, Daebeom;Lee, Jong Eun
    • Journal of the Korea Convergence Society
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    • v.10 no.6
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    • pp.203-218
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    • 2019
  • Using the sample of 104 mutual savings banks inspected by the Financial Supervisory Service (FSS) on June 2011, this study examines if mutual savings banks manage BIS capital adequacy ratio using allowance for bad debts through comparison of BIS capital adequacy ratio before and after the 2011 when mutual savings banks experienced a large-scale restructuring by financial supervisory authorities. We find that mutual savings banks mainly use the allowance for bad debts to manage BIS capital adequacy ratio. It also shows that mutual savings banks with a business suspension order by FSS manage BIS capital adequacy ratio more than the others. Lastly, we find that Non Big4 auditors as well as Big 4 auditors don't effectively audit the use of the allowance for bad debts for mutual savings banks to manage their BIS capital adequacy ratio.