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151.
Andrew M. Edmonds Mushtaq A. Sobhan Varun K. A. Sreenivasan Ekaterina A. Grebenik James R. Rabeau Ewa M. Goldys Andrei V. Zvyagin 《Particle & Particle Systems Characterization》2013,30(6):506-513
Bioprobes based on fluorescent ruby nanoparticles, which are suitable for ultrasensitive imaging, are reported. A stable aqueous/buffer colloid, permitting facile conjugation to proteins, is produced by femtosecond laser ablation of ruby and the nanoparticles (mean size 17 nm) are photostable, with long lifetime (1–4 ms) 694 nm emission. With time‐gating complete (>20 dB) suppression of cell autofluorescence and suppression of exogenous fluorophores is observed. Nanoparticles are imaged in as‐grown cells and those immunolabeled with quantum dots. Immunoassay binding to target biomolecules is also demonstrated. 相似文献
152.
Philip L. Southwick Klaus M. Hahn Jean Chao Patrick L. Perry Allan S. Wagman Marc Wagner Alan S. Waggoner 《Journal of fluorescence》1995,5(2):231-235
A red fluorescent dye of the oxonol class, bis-[1-(carboxymethyl)barbituric acid-(5)]-pentamethinoxonol, has been synthesized and, in the form of the succinimidyl active ester, has been applied to antibody labeling for application to flow cytometry and to imaging of tissue sections. The new dye, named CMOX (for carboxymethyloxonol), shows maximum excitation at 583 nm and emission at 611 nm, with a quantum yield of 0.2 in aqueous buffer and methanol. Antibodies labeled with the new dye show favorable brightness, photostability, and low levels of nonspecific binding. 相似文献
153.
V. Swaminathan 《Discrete Mathematics》2006,306(14):1624-1636
A graph G(V,E) is called super edge-magic if there exists a bijection f from V∪E to {1,2,3,…,|V|+|E|} such that f(u)+f(v)+f(uv)=c(f) is constant for any uv∈E and f(V)={1,2,3,…,|V|}. Such a bijection is called a super edge-magic labeling of G. The super edge-magic strength of a graph G is defined as the minimum of all c(f) where the minimum runs over all super edge-magic labelings of G and is denoted by sm(G). The super edge-magic strength of some families of graphs are obtained in this paper. 相似文献
154.
I.D. Gray 《Discrete Mathematics》2006,306(22):2878-2892
A sparse anti-magic square is an n×n array whose non-zero entries are the consecutive integers 1,…,m for some m?n2 and whose row-sums and column-sums form a set of consecutive integers. We derive some basic properties of these arrays and provide constructions for several infinite families of them. Our main interest in these arrays is their application to constructing vertex-magic labelings for bipartite graphs. 相似文献
155.
156.
Michael A. Bekos Michael Kaufmann Antonios Symvonis Alexander Wolff 《Computational Geometry》2007,36(3):215-236
We introduce boundary labeling, a new model for labeling point sites with large labels. According to the boundary-labeling model, labels are placed around an axis-parallel rectangle that contains the point sites, each label is connected to its corresponding site through a polygonal line called leader, and no two leaders intersect. Although boundary labeling is commonly used, e.g., for technical drawings and illustrations in medical atlases, this problem has not yet been studied in the literature. The problem is interesting in that it is a mixture of a label-placement and a graph-drawing problem.
In this paper we investigate several variants of the boundary-labeling problem. We consider labels of identical or different size, straight-line or rectilinear leaders, fixed or sliding ports for attaching leaders to sites and attaching labels to one, two or all four sides of the bounding rectangle. For any variant of the boundary labeling model, we aim at highly esthetical placements of labels and leaders. We present simple and efficient algorithms that minimize the total leader length or, in the case of rectilinear leaders, the total number of bends. 相似文献
157.
CLAIRE BOISSET HENRI CHANZY MARTIN SCHULEIN BERNARD HENRISSAT 《Cellulose (London, England)》1997,4(1):7-20
Because cellulases are finding more applications in the textile and detergent industries, their effect on cotton fibres must
be evaluated. For this purpose, the action of a recombinant cellulase, endoglucanase V from the fungus Humicola insolens,
has been followed by scanning electron microscopy (SEM) in classical longitudinal views as well as in cross-sections of cotton
fibres. The experiments were conducted at large enzyme dilution typical of conditions where cellulases are used for biopolishing,
i.e. for the removal of defects created by mechanical abrasion. Endoglucanase V appears to restrict its action to the hydrolysis
of the loose fibrils created at the surface of the fibres and no indication of extensive enzyme penetration and damage to
the interior of the fibres could be detected by SEM. The adsorption sites for endoglucanase V on cotton fibres were examined
by transmission electron microscopy (TEM) on ultrathin cross-sections after immuno-gold labeling of the enzyme. This approach
showed that the enzymes did not penetrate the fibres but remained at their surface. The use of an immuno-gold labeled cellulase
provides a new way to probe the surface features of cotton fibres
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
158.
We prove that for any planar graph G with maximum degree Δ, it holds that the chromatic number of the square of G satisfies χ(G2) ≤ 2Δ + 25. We generalize this result to integer labelings of planar graphs involving constraints on distances one and two in the graph. © 2002 Wiley Periodicals, Inc. J Graph Theory 42: 110–124, 2003 相似文献
159.
A characterisation by 14N NMR of the binary nitrides AlN and BN is presented. Both the static and magic angle spinning (MAS) lineshapes have been investigated in order to determine, or set upper limits on, the nuclear quadrupole coupling (Cq) at the nitrogen site. Additional data are given for the Cq values at the Al and B sites. A comparison is made with other similar (mainly wurtzite) binary compounds for which Cq is known at each atomic site. 相似文献
160.