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191.
CD43 (sialophorin, leukosialin) is a heavily sialylated surface protein expressed on most leukocytes and platelets including T cells. Although CD43 antigen is known to have multiple and complex structure, exact function of CD43 in each cell type is not completely understood. Here we evaluated the role of CD43 in Fas (CD95)-induced cell death in human T lymphoblastoid cell line, Jurkat. Crosslinking CD43 antigen by K06 mAb increased the Fas-mediated Jurkat cell apoptosis and the augmentation was inhibited by treatment with caspase inhibitors. Further, CD43 signaling of Jurkat cells induced Fas oligomerization on the cell surfaces implying that CD43 ligation have effects on early stage of Fas-induced T cell death. These also suggest that CD43 might play an important role in contraction of the immune response by promotion of Fas-induced apoptosis in human T cells. 相似文献
192.
Tam-Chang SW Helbley J Carson TD Seo W Iverson IK 《Chemical communications (Cambridge, England)》2006,(5):503-505
We have developed an approach to generate micropatterns of anisotropic organic materials which exploits the self-organization, driven by pi-stacking and hydrophobic interactions, of an ionic perylenebis(dicarboximide) in aqueous solutions. 相似文献
193.
194.
Ji-Tae Hong Hyunwoong Seo Dong-Gil Lee Jin-Ju Jang Tae-Pung An Hee-Je Kim 《Journal of Electrostatics》2010,68(3):205-211
The dye coloring process on a nano-porous TiO2 thin film for DSSCs was studied using an electrostatic spraying (ESS) method. In this study, dye coating experiments were performed using homemade ESS equipment. The coating patterns on the TiO2 thin film are changed by adjusting the applied voltages of the ESS system. The geometry of the coating patterns is observed by a charge-coupled device (CCD) camera. The TiO2 thin film is fabricated by controlling the electric field which allows a uniform color distribution to be obtained with a high dyeing capacity. The colored TiO2 thin films are compared with those obtained using a conventional immersed dye solution by means of an UV–vis spectrometer. The performance of this novel coloring process was confirmed by measuring I–V curve characteristics. 相似文献
195.
Juan Lü Yanlin Huang Liang Shi Hyo Jin Seo 《Applied Physics A: Materials Science & Processing》2010,99(4):859-863
The blue-emitting phosphors of Eu2+-doped Na2CaMg(PO4)2 were prepared by high-temperature solid-state reaction. The crystal phase formation was confirmed by X-ray powder diffraction
measurement. The luminescence properties were investigated by photoluminescence excitation and emission spectra. The phosphor
exhibited the blue luminescence due to the 4f65d1→4f7 transition of Eu2+ ions under the excitation of near UV light. The influence of temperature on the luminescence intensities and decay lifetimes
of Eu2+ was investigated. An unusual increase of the decay lifetimes of the 4f65d emission of Eu2+ ion is observed in Na2CaMg(PO4)2 from 10 K to room temperature. The thermal stability of the luminescence of Eu2+-doped Na2CaMg(PO4)2 was discussed. 相似文献
196.
Hyun Suk Seo Yeong Mu Ko Jae Won Shim Joong-Ki Kook Byung Hoon Kim 《Applied Surface Science》2010,257(2):596-602
Plasma surface modification can be used to improve the surface properties of commercial pure Ti by creating functional groups to produce bioactive materials with different surface topography. In this study, a titanium surface was modified with acrylic acid (AA) using a plasma treatment and immobilized with bioactive arginine-glycine-aspartic acid (RGD) peptide, which may accelerate the tissue integration of bone implants. Both terminals containing the -NH2 of RGD peptide sequence and -COOH of poly(acrylic acid) (PAA) thin film were combined with a covalent bond in the presence of 1-ethyl-3-3-dimethylaminopropyl carbodiimide (EDC). The chemical structure and morphology of AA film and RGD immobilized surface were investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). All chemical analysis showed full coverage of the Ti substrate with the PAA thin film containing COOH groups and the RGD peptide. The MC3T3-E1 cells were cultured on each specimen, and the cell alkaline phosphatase (ALP) activity were examined. The surface-immobilized RGD peptide has a significantly increased the ALP activity of MC3T3-E1 cells. These results suggest that the RGD peptide immobilization on the titanium surface has an effect on osteoblastic differentiation of MC3T3-E1 cells and potential use in osteo-conductive bone implants. 相似文献
197.
We have studied the effect of perpendicular magnetic fields and temperatures on nonlinear electronic transport in amorphous Ta superconducting thin films. The films exhibit a magnetic field-induced metallic behavior intervening the superconductor-insulator transition in the zero temperature limit. We show that the phase-identifying nonlinear transport in the superconducting and metallic phases arises from an intrinsic origin, not from an electron heating effect. The nonlinear transport is found to accompany an extraordinarily long voltage response time. 相似文献
198.
The purpose of this study was to find optimum treatment conditions for selective photothermolysis by evaluating internal–external heat distributions according to different cooling methods. The 1,064-nm Nd:YAG laser was transmitted into a skin-mimicking phantom with different cooling conditions, and its minimum temperatures and sub-zero times were measured. The cooling methods were classified into a total of eight conditions composed of five cryogen spray cooling conditions and three air cooling conditions. Based on the experimental results, condition 2 was selected as the optimum cooling condition for selective photothermolysis obtained from the cryogen spray cooling method. 相似文献
199.
We prove that the Hilbert functions of Gorenstein Artin algebras R/I of embedding dimension four are unimodal provided I has a minimal generator in degree less than five. It is still an open question as to whether all Gorenstein Hilbert functions in codimension four are SI-sequences. It is not even known if they are all unimodal. In this article, we prove that Hilbert functions of all Gorenstein Artin algebras starting with (1, 4, 10, 20, h 4,…), where h 4 = 34 are unimodal. Combining this with previously known results, we obtain that all Gorenstein Hilbert functions (1, 4, h 2, h 3, h 4,…4, 1) are unimodal if h 4 ≤ 34. 相似文献
200.
Hyun-Joung Kwon Jeong-Ah Seo Takashi Iwahashi Yukio Ouchi Doseok Kim Hyung Kook Kim Yoon-Hwae Hwang 《Current Applied Physics》2013,13(1):271-279
This study examined the acoustic phonon mode of ionic liquids consisting of 1-alkyl-3-methyl-imidazolium family (CnMIM) cations with n values ranging from 2 to 10 and bis(trifluoromethylsulfonyl)amide (TFSA) anion in the temperature range from 300 K to 100 K. [CnMIM]+[TFSA]? showed depolarized (VH) components of Brillouin peaks at temperatures below the glass transition temperature when n is larger than 4. On the other hand, in the case of ionic liquids with different anions, such as [C4MIM]+[BF4]?, [C4MIM]+[PF6]? and [C8MIM]+[BF4]?, the VH component of Brillouin peaks was not observed in the temperature range investigated. The dielectric loss spectra showed that the temperature dependence of alkyl chain domain relaxation of all ionic liquids followed the Arrhenius law and showed an increase in activation energy at the temperature where the VH component of Brillouin peak appeared. These results suggest that the observed depolarized component of Brillouin peak might originate from uniquely induced polarization in the 2nd domain composed of head groups of cations and anions. 相似文献