• 제목/요약/키워드: CD&R

검색결과 787건 처리시간 0.031초

Electrochemical Characterization of Multilayered CdTe/PSS Films Prepared by Electrostatic Self-assembly Method

  • Rabbani, Mohammad Mahbub;Yeum, Jeong Hyun;Kim, Jungsoo;Nam, Dae-Geun;Oh, Weontae
    • Transactions on Electrical and Electronic Materials
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    • 제15권5호
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    • pp.257-261
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    • 2014
  • Multilayered CdTe/PSS films were prepared by the electrostatic self-assembly method in an aqueous medium. Positively-charged cadmium telluride (CdTe) nanoparticles and anionic polyelectrolyte, poly (sodium 4-styrene sulfonate) (PSS) were assembled alternately in order to build up a multilayered film structure. A linear proportion of absorbance to the number of bilayers suggests that an equal amount of CdTe was adsorbed after each dipping cycle, which resulted in the buildup of a homogenous film. The binding energies of elements (Cd and Te) in multilayered CdTe/PSS film shifted from those of the CdTe nanoparticles in the pure state. This result indicates that the interfacial electron densities were redistributed by the strong electrostatic interaction between the oppositely-charged CdTe and PSS. Electrochemical properties of the multilayered CdTe/PSS films were studied in detail by cyclic voltammetry (CV).

Epirubicin Inhibits Soluble CD25 Secretion by Treg Cells Isolated from Diffuse Large B-cell Lymphoma Patients

  • Li, Lan-Fang;Wang, Hua-Qing;Liu, Xian-Ming;Ren, Xiu-Bao
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권3호
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    • pp.1721-1724
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    • 2013
  • Objective: To investigate the effect of epirubicin on soluble CD25 (sCD25) secretion by CD4+CD25+ regulatory T (Treg) cells isolated from diffuse large B-cell lymphoma (DLBCL) patients. Methods: Treg cells were isolated from the peripheral blood mononuclear cells isolated from the newly diagnosed DBLCL patients. The concentration of sCD25 in the supernatant was determined with a commercial sCD25 (IL-2R) enzyme-linked immunosorbent assay (ELISA) kit. The fluorescence intensity of CD25 was detected by flow cytometry. Results: Cell survival rate was significantly decreased along with the increase of epirubicin concentration after treatment for 24 h. There was also a significant difference in the concentration of sCD25 between the epirubicin group and the control group (P<0.01). A positive correlation between the Treg cells survival rate and the concentration of sCD25 was detected (r=0.993, P<0.01). When equal numbers of CD4+CD25+ Treg cells of the epirubicin group and the control group were cultured for another 24 h without epirubicin the CD25 fluorescence intensity on the surface of Treg cells was obviously higher in the epirubicin group than that in the control group (P<0.01), while the sCD25 concentration in the supernatant in the epirubicin group was significantly lower than that in the control group (P<0.05). Conclusion: Epirubicin may improve the body's immune functions by inhibiting the sCD25 secretion by Treg cells in DLBCL patients.

Thiocyanat 및 1,2-Diaminocyclohexane 리간드로 구성된 카드뮴(II) 착물의 합성 및 결정구조 (Synthesis and Crystal Structure of the Cadmium(II) Complex with Thiocyanate and 1,2-Diaminocyclohexane Ligands)

  • 김인회;서승욱;김종혁;김진규;서일환
    • 한국결정학회지
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    • 제12권4호
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    • pp.207-211
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    • 2001
  • Cd(SCN)₂{CH/sub 6/H/sub 10/(NH₂)₂}₂(1) 착물을 합성하고 단결성 X-선 회절법으로 구조를 규명하였다. 이 착물은 단사정계, 공간국 P2₁/ space group with a=11.842(2), b=7.926(2), c=11.291(2) Å, β=106.73(3)°V=1014.8(4)Ų, Z=2 로 결정화되었으며, 1775 개의 독립적인 회절반점에 대한 최종 신뢰도 인자 R₁및 ωR₂값은 각각 0.0518 및 0.1315이었다. 착물의 결정 구조는 2개의1,2-Diaminocyclohexane리간드의 질소 원자 xy 평면에서 Cd(II) 금속원자에 chelate 되어 5-membered ring을 형성하며, 2개의 thiocyanate 리간드의 황 원자가 z 축 방향으로 Cd(II) 금속 원자에 트란스 형태로 결합함으로 써 z축 방향으로 약간 늘러진 팔면체 구조의 착물을 형성한다.

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해양심층수염 절임배추와 시판 절임배추의 품질변화 비교 (Comparison of quality changes in brined cabbage with deep sea water salt and a commercial brined cabbage product)

  • 임지훈;정지희;김동수;김영명;김병목
    • 한국식품저장유통학회지
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    • 제21권5호
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    • pp.676-687
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    • 2014
  • 본 연구에서는 천일염, 정제염, 해양심층수염을 사용하여 제조한 절임배추의 냉장저장($0^{\circ}C$) 중 품질변화 및 시판제품과의 품질특성을 비교 조사하였다. pH의 경우 저장기간 전반적으로 S, R, D 구가 CS, CR, CD 구에 비해 높았고, 적정산도는 저장기간 전반적으로 CS, CR, CD 구가 S, R, D 구에 비해 높았다. 수분함량은 저장기간이 경과할수록 삼투압 작용에 의하여 모든 실험군에서 감소하였고, 염도는 S, R, D 구가 2.0~2.6%로 CS, CR, CD 구(0.9~1.8%)에 비해 저장기간 동안 유의적으로 높았다. 총균수 및 유산균수는 CS, CR, CD 구가 저장 1주 이후부터 급격히 증가하여 저장기간 동안 S, R, D 구에 비해 유의적으로 높게 나타나 pH 및 적정산도의 변화에 영향을 주었다. 경도와 씸힘성의 경우 모든 실험군에서 저장기간이 경과함에 따라 감소하였고 저장기간 동안 해양심층수염으로 제조한 절임배추(D)의 경도가 다른 실험군에 비해 유의적으로 높게 나타났다. 유리아미노산 총량은 CD 구가 가장 높았고 D 구가 가장 낮았으며, 필수아미노산의 비율은 소금의 종류에 따른 큰 차이를 보이지 않았지만, 비필수아미노산의 비율은 해양심층수염으로 제조 된 시판제품이 가장 높았다. 유기산 총량은 CD 구가 가장 높았고 해양심층수염으로 제조한 D와 정제염으로 제조한 R 구가 가장 낮았다. 무기질 총함량의 경우에도 CD 구가 실험군 중 가장 높았고, D, S, R, CR, CS 순으로 낮게 나타났다. K와 Mg 함량은 해양심층수염으로 제조한 D 구가 실험군 중 가장 높았고, Na 함량은 CD구가 가장 높았다. 관능적 외관, 산미 및 전체적 기호도는 모든 실험군에서 저장기간이 경과함에 따라 감소하였으나 해양심층수염으로 제조한 절임배추(D)의 외관, 산미 및 전체적 기호도는 저장기간 동안 다른 실험군에 비해 유의적으로 높은 평가를 받았다. 즉, 해양심층수염으로 절임배추를 제조할 경우 천일염이나 정제염으로 절임한 배추에 비해 관능적으로 우수하고 무기질, 유기산 함량이 높은 양질의 절임배추를 제조할 수 있을 것으로 사료되었다.

양재지역 ICT 중소기업의 R&D 역량에 관한 연구 (A Study on the R&D Capabilities of ICT SMEs in Yangje District)

  • 김동욱;김대호
    • 한국융합학회논문지
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    • 제8권7호
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    • pp.265-272
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    • 2017
  • 서울시와 미래창조과학부는 4 차산업을 이끌어갈 미래성장동력의 거점으로 양재지역에 "R&CD 클러스터" 조성을 추진하고 있다. 양재지역은 대기업 연구소 및 ICT중소기업이 다수 밀집되어 있고 서울의 남쪽에 위치하여 교통, 교육, 여가생활 등의 지리적 이점을 갖고 있다. 양재지역의 성공적인 클러스터 조성을 위한 초기연구로 정량적 분석으로 "한국 SMTp 2017 DVD ROM"의 한국 기업정보 DB 및 콘텐츠를 활용하여 양재지역의 ICT 중소기업의 현황을 파악하였고 정성적 분석으로 2016년 12월 8일부터 2017년 1월 7일 동안 설문을 실시하여 ICT기업의 R&D활동을 조사하였다. 마지막으로 양재지역 ICT기업의 R&D역량 강화를 위한 시사점을 도출하였다.

Assessment of Risks and Benefits of Using Antibiotics Resistance Genes in Mesenchymal Stem Cell-Based Ex-Vivo Therapy

  • Narayan Bashyal;Young Jun Lee;Jin-Hwa Jung;Min Gyeong Kim;Kwang-Wook Lee;Woo Sup Hwang;Sung-Soo Kim;Da-Young Chang;Haeyoung, Suh-Kim
    • International Journal of Stem Cells
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    • 제16권4호
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    • pp.438-447
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    • 2023
  • Recently, ex-vivo gene therapy has emerged as a promising approach to enhance the therapeutic potential of mesenchymal stem cells (MSCs) by introducing functional genes in vitro. Here, we explored the need of using selection markers to increase the gene delivery efficiency and evaluated the potential risks associated with their use in the manufacturing process. We used MSCs/CD that carry the cytosine deaminase gene (CD) as a therapeutic gene and a puromycin resistance gene (PuroR) as a selection marker. We evaluated the correlation between the therapeutic efficacy and the purity of therapeutic MSCs/CD by examining their anti-cancer effect on co-cultured U87/GFP cells. To simulate in vivo horizontal transfer of the PuroR gene in vivo, we generated a puromycin-resistant E. coli (E. coli/PuroR) by introducing the PuroR gene and assessed its responsiveness to various antibiotics. We found that the anti-cancer effect of MSCs/CD was directly proportional to their purity, suggesting the crucial role of the PuroR gene in eliminating impure unmodified MSCs and enhancing the purity of MSCs/CD during the manufacturing process. Additionally, we found that clinically available antibiotics were effective in inhibiting the growth of hypothetical microorganism, E. coli/PuroR. In summary, our study highlights the potential benefits of using the PuroR gene as a selection marker to enhance the purity and efficacy of therapeutic cells in MSC-based gene therapy. Furthermore, our study suggests that the potential risk of horizontal transfer of antibiotics resistance genes in vivo can be effectively managed by clinically available antibiotics.

이중 도핑을 이용한 고효율 적색 인광 유기발광소자 (High Efficiency Red Phosphorescent Organic Light Emitting Devices Using the Double Dopant System)

  • 장지근;신현관;김원기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.351-352
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    • 2008
  • A new high efficient red PhOLED using a host of $Bebq_2$ and double dopants of $(pq)_2$Ir(acac) and SEC-R411 have been fabricated and evaluated. The device doubly doped with $(pq)_2$Ir(acac) and SFC-R411 showed the current efficiency improvement of 22% under a luminance of 10000 cd/$m^2$ in comparision with the device singly doped with SFC-R411. The luminance, current efficiency and central wavelength of the doubly doped device were 9300 cd/$m^2$ at 7V, 11.1 cd/A under a luminance of 10000 cd/$m^2$ and 625 nm, respectively.

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Chiral Recognition Models of Enantiomeric Separation on Cyclodextrin Chiral Staionary Phases

  • 이선행;김병학;이영철
    • Bulletin of the Korean Chemical Society
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    • 제16권4호
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    • pp.305-309
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    • 1995
  • The enantiomeric separation of several amino acid derivatives by reversed-phase liquid chromatography using two (R)-and (S)-naphthylethylcarbamate-β-cyclodextrin(NEC-β-CD) bonded stationary phases was studied to illustrate the chiral recognition model of the enantiomeric separation. The retention and enantioselectivity of the chiral separations with (R)-and (S)-NEC-β-CD bonded phases were compared with similar separations with the native β-CD stationary phases. Especially, the enantioselectivity and elution orders between the derivatized amino acid enantiomers are carefully examined. These results can be illustrated by the chiral recognition models involving inclusion complexation, π-π interaction, and/or hydrophobic interaction. Inclusion complexation and hydrophobic interaction of the naphthyl group of the NEC moiety seem to be major chiral recognition components in the enantiomeric separation of 2,4-dinitrophenyl amino acids and dabsyl amino acids on (R)-and (S)-NEC-β-CD columns. For dansyl amino acids, only the inclusion complexation is the dominant factor. Three different chiral recognition models containing π-π interaction, inclusion complexation and hydrogen bonding were proposed for the separation of the 3,5-dinitrobenzoyl amino acid enantiomers, depending on the size and shape of amino acids.

수소제조에 관한 박막형 CdS-TiO2 복합 광촉매계의 표면처리 효과 (Effect of Surface Treatment of CdS-TiO2 Composite Photocatalysts with Film Type on Hydrogen Production)

  • 장점석;소원욱;김광제;문상진
    • 한국수소및신에너지학회논문집
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    • 제13권1호
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    • pp.34-41
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    • 2002
  • CdS and $TiO_2$ nanoparticles were made by the precipitation method and sol-gel method, respectively, and they were mixed mechanically and then treated with the hydrothermal processing. CdS-$TiO_2$ composite particulate films were thus prepared by casting CdS-$TiO_2$ mixed sol onto $SnO_2$ conducting glass and a subsequent heat-treatment at $400^{\circ}C$. Again, the physico-chemical and photoelectrochemical properties of these films were controlled by the surface treatment with $TiCl_4$ aqueous solution. The photocurrents and the hydrogen production rates measured under the present experimental conditions varied in the range of $3.5{\sim}4.5mA/cm^2$ and $0.3{\sim}1.8cc/cm^2$-hr, respectively, and showed the maximum values at the $CdS/[CdS+TiO_2]$ mole ratio of 0.2. Also, the surface treatment with $TiCl_4$ aqueous solution caused a considerable improvement in the photocatalytic activity, Probably as a result of close contacts between the primary particles by the etching effect of $TiCl_4$ It was found that the photoelectrochemical performance of these particulate films could be effectively enhanced by this approach.

Three Crystal Structures of Dehydrated $Cd^{2+}$ and $Rb^+$ Exchanged Zeolite A, $Cd_xRb_{12-2x}-A,$ x=4.0, 5.0 and 5.95

  • Song, Yeong-Sim;Kim, Un-Sik;Kim, Yang;Kim, Duk-Soo
    • Bulletin of the Korean Chemical Society
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    • 제11권4호
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    • pp.328-331
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    • 1990
  • Three crystal structures of dehydrated Cd(II) and Rb(I) exchanged zeolite A, $Cd_{4.0}Rb_{4.0}-A (a = 12.204(3) {\AA}), Cd_{5.0}Rb_{2.0}-A (a = 12.202(1) {\AA}),$ and $Cd_{5.95}Rb_{0.1}-A (a = 12.250(2) {\AA}),$ have been determined by single-crystal X-ray diffraction techniques. Their structures were solved and refined in the cubic space group Pm3m at $21(1)^{\circ}C.$ All crystals were ion exchanged in flowing streams of mixed $Cd(NO_3)_2·4H_2O$ and $RbNO_3$ aqueous solution with total concentration of 0.05 M. All crystals were dehydrated at ca. $450^{\circ}C$ and $2×10^{-6}$ Torr for 2 days. In all of these structures, $Cd^{2+}$ ions are found on threefold axes, each nearly at the center of a 6-oxygen ring. The first three $Rb^+$ ions per unit cell preferentially associate with 8-oxygen rings, and additional $Rb^+$ ions, if present, are found on threefold axes in the large cavity. The final $R_1$ and $R_2$ values for the three structures are 0.087 and 0.079, 0.059 and 0.067, and 0.079 and 0.095, respectively.