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1.
Altan Kara Perihan Ünak Cenk Selçuki Özlet Akça E. İlker Medine Serhan Sakarya 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):807-813
This research aims to investigate the interaction between phytohemagglutinin-L (PHA-L) and sialic acid, which is abundant on the breast cancer cell (MCF-7) surface and displays monosaccharide characteristics, by experimental and computational methods. Experimentally, CdSe/CdS nanoparticles (QDs) were synthesized; PHA-L was conjugated with QDs and labeled with 125I. Radiolabeling yield was found to be 97 ± 1.2 %. Afterwards, in vitro bioaffinities of radiolabeled PHA-L conjugated QDs have been investigated on MCF-7 cells and it has been observed that the cell incorporation increased with time. The results indicated that 125I labeled QD-PHA-L conjugates represent significant affinity on MCF-7 cells. In the second step of the study, the crystal structure of carbohydrate interaction surface of PHA-L was extracted from the crystal structure of PHA-L. The interactions between this surface and sialic acid were calculated by computational tools. These calculations revealed specific interactions between PHA-L and sialic acid. Semi-empirical methods, PM3 and AM1, were used in these calculations. Significant outcomes have been obtained from the experimental and computational studies and these results demonstrated that PHA-L may be an effective agent for imagining MCF-7 cells. 相似文献
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Veith M Lee J Martinez Miró M Akkan CK Dufloux C Aktas OC 《Chemical Society reviews》2012,41(15):5117-5130
Biphasic solid state composites of the type metal/metal oxide or element/element oxide can be synthesized in one pot chemical reactions using so called molecular "single source precursors". Due to their singular genesis these composites show peculiar hetero-structures based on core-shell hierarchies such as superlattices and composite nanospheres or nanowires. They exhibit superior or new functional properties compared to their individual constituent compounds. In the current work, we review in particular the synthetical and mechanistical approach of bi-phasic (Al/Al(2)O(3)) nanostructures such as nanospheres, nanowires and nanoloops using a single source precursor. Other bi-phasic materials of the general formula M/MO(x) (for example M = Ge, Sn, Pb) are addressed for comparison. The impact of different synthetical conditions as well as of modification of surfaces by laser techniques and their technological relevance are presented briefly. Additionally, functional applications of the prepared surfaces are explained with some outstanding case studies. These case studies are primarily concerned with their use as biomaterials and their application in medicine as well as with their use as thin films for optics and functional surfaces. 相似文献
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Mediterranean Journal of Mathematics - In this paper, we study Lorentzian hypersurfaces in Minkowski 5-space with non-diagonalizable shape operator whose characteristic polynomial is (t − k... 相似文献
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Davis Marauo Gümeci Cenk Kiel Courtney Hope-Weeks Louisa J. 《Journal of Sol-Gel Science and Technology》2011,58(2):535-538
For the first time, the simple epoxide addition, sol–gel method has been employed to successfully prepare porous, high surface
area manganese (II) aerogel nanomaterials. These uniform materials can then undergo calcination at relatively low temperature
to selectively yield the mixed-valent Mn3O4 complex illustrating both an ease of preparation and synthesis versatility. 相似文献
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S Cenk B Demirata M L Ove?oglu G Ozen 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2001,57(12):2367-2372
Glasses with the composition of (1 - x)TeO2 + (x)WO3, where x = 0.15, 0.25 and 0.3 were prepared and, their thermal and absorption measurements were carried out. Differential thermal analysis (DTA) curves taken in the 23-600 degrees C temperature range with a heating rate of 10 degrees C/min reveal a change in the value of the glass transition temperature, Tg, while crystallization was not observed for the glasses containing a WO3 content of more than 15 mol%. All the glasses were found to be moisture-resistant. The absorption bands corresponding to the absorption of the 1G4, 3F2, 3F3 and 3F4, 3H5 and 3H4 levels from the 3H6 ground level of the Tm3+ ion were observed in the optical absorption spectra. Integrated absorption cross-sections of each band except that of 3H5 level was found to vary with the glass composition. Judd-Ofelt analysis was carried out for the samples doped with 1.0 mol% Tm2O3. The omega2 parameter shows the strongest dependence on the host composition and it increases with the increasing WO3 amount. The value of omega4 increases rather slowly while the value of omega6 is practically independent of the composition. The strong dependence of the parameter omega2 indicates that this parameter is related to the structural change and the symmetry of the local environment of the Tm3+ ions in this glass. 相似文献
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Cenk Argon 《Optics Communications》2009,282(4):500-503
Optical orthogonal code (OOC) sequences are assigned to optical code-division multiple-access (OCDMA) network users, who are able to transmit data asynchronously. In this work, we propose a semi-random OOC design technique based on extended sets, where the input parameters are the sequence weight, number of sequences (i.e., users), and a target sequence length. The design method under consideration is able to converge to the desired short OOC lengths given the number of iterations during the execution of the algorithm is sufficiently large. 相似文献
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Cenk Ulu Mujde Guzelkaya Ibrahim Eksin 《International Journal of Approximate Reasoning》2013,54(9):1421-1433
In this study, a new centroid type reduction method is proposed for piecewise linear interval type-2 fuzzy sets based on geometrical approach. The main idea behind the proposed method relies on the assumption that the part of footprint of uncertainty (FOU) of an interval type-2 fuzzy set (IT2FS) has a constant width where the centroid is searched. This constant width assumption provides a way to calculate the centroid of an IT2FS in closed form by using derivative based optimization without any need of iterations. When the related part of FOU is originally constant width, the proposed method finds the accurate centroid of an IT2FS; otherwise, an enhancement can be performed in the algorithm in order to minimize the error between the accurate and the calculated centroids. Moreover, only analytical formulas are used in the proposed method utilizing geometry. This eliminates the need of using discretization of an IT2FS for the type reduction process which in return naturally improves the accuracy and the computation time. The proposed method is compared with Enhanced Karnik–Mendel Iterative Procedure (EKMIP) in terms of the accuracy and the computation time on seven test fuzzy sets. The results show that the proposed method provides more accurate results with shorter computation time than EKMIP. 相似文献
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Density functional and molecular orbital theory calculations on models for cobalamin suggest that NO binds similarly to the Co(II) and Co(III) oxidation states. However, Co(III) can bind water far more strongly than Co(II) as a sixth ligand, so that the competition between water and NO complexation strongly favors water for Co(III) in the gas phase. Although the Co(II) oxidation state is found to bind water slightly more strongly than NO in the gas phase, the inclusion of solvation effects via the polarizeable continuum model makes NO binding more favorable. Thus, the experimentally observed ability of cob(II)alamin to bind NO in aqueous solution is the result of its weak complexation with water and the relatively poor solvation of NO. Calculated vibrational frequencies support the interpretation of the cob(II)alamin-NO complex as being cob(III)alamin-NO-, although the DFT calculations underestimate the degree of charge transfer in comparison to Hartree-Fock calculations. 相似文献