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971.
The amperometric and EQCM aptasensors based on DNA aptamers immobilized by avidin‐biotin method or by electrostatic adsorption onto multiwalled carbon nanotube layer contained methylene blue (MB) have been developed and examined for thrombin detection in buffer and in spiked blood serum. The presence of MB increases the binding capacity of the surface layer and enhances the range of thrombin concentrations to be determined. This results in significant improvement of analytical characteristics of thrombin detection. The EQCM aptasensors allowed us to detect 0.3–100 nM and amperometric aptasensors 10–1000 nM of thrombin. 相似文献
972.
973.
The definition and properties of an abstract and very general nonparametric integral of the Calculus of Variations is presented. In harmony with the Lewy-McShane approach, the nonparametric integral ∝ f, for set functions ? taking their values in a Banach space E, is defined in terms of its associated parametric integral. For the latter use is made of the abstract parametric integral proposed by Cesari in Rn and then extended to Banach spaces by Breckenridge, Warner, and the authors. A condition (c) is shown to be relevant for the existence of the integral, and is preserved by the nonlinear operation f. Also, for f nonnegative, a Tonelli-type theorem is proved in the sense that the so defined Weierstrass integral ∝ f is always larger than or equal to the corresponding Lebesgue integral, and equality holds if and only if absolute continuity conditions hold. In the proof a suitable martingale is associated and a convergence theorem for martingales is applied. Applications to the calculus of variations will follow. 相似文献
974.
The transportation problem with fuzzy supply values of the deliverers and with fuzzy demand values of the receivers is analysed. For the solution of the problem the technique of parametric programming is used. This makes it possible to obtain not only the maximizing solution (according to the Bellman-Zadeh criterion) but also other alternatives close to the optimal solution. 相似文献
975.
The well-understood roughening transition of an interface in the d = 3 Ising model implies an essential singularity in the string tension of the dual Z2 gauge model. The roughening transition corresponds to the delocalization of the string due to strong long-wavelength fluctuations, and this reformulation can be generalized to other gauge groups and to d = 4 also. It is not a deconfining transition - it is expected to occur deep in the confining region - but its presence would raise serious questions about the continuation of strong coupling expansions of the tension beyond this point. In this paper predictions on the roughening transition are confronted with the available information on the string tension for different gauge groups in three dimensions. 相似文献
976.
Atmospheric electricity measurements made during the last decade at Poona using balloon-borne sondes are briefly reviewed. The vertical distribution of potential gradient in the free atmosphere follows theoretical values only during the monsoon months, when the air is comparatively free from dust. During the summer months, the potential gradient is constant above the exchange layer and this is associated with the presence of the deep, dense dust layer that lies over the region and extends to over 10 km. into the atmosphere. The increase with height of the potential gradient above the 10 km. level during winter is shown to be closely related to the presence of the subtropical jet stream, which presumably transports electric charges to the upper levels over Poona. 相似文献
977.
A systematic study of the dependence of the collective quantities (energies and matrix elements of the E2, M1 and E0 moments) on the form of approximations to the potential energy V and the inertia tensor B is performed. Various approximations used up to now are tested. Macroscopic-microscopic values for V and cranking results for B are taken as a reference. The collective quantities are calculated by solving the Schrödinger equation corresponding to the collective Bohr hamiltonian. The contribution of all nucleons is explicitly taken into account; no renormalization factors are used. Spherical, transitional and deformed even-even nuclei are considered. The quality of various approximations for V and B used in the boson-expansion method is discussed. Large effects of the microstructure of the inertia tensor B are obtained and commented on. 相似文献
978.
3-O-Methyl-6-deoxy-D -allose (V) and its methyl β-D -pyranoside (IV) have been synthesized and obtained in a crystalline state, although in low yield, starting from methyl 6-deoxy-β-D -allopyranoside (I) via the 2,4-di-O-benzoyl derivative II. 相似文献
979.
Anna Salvadori 《Rendiconti del Circolo Matematico di Palermo》1980,29(2):277-290
We introduce two new sufficient conditions for the existence of Burkill-Cesari integral: the «quasi additivity by refinement» and the «almost quasi additivity by refinement», that are intermediate between the well-known concepts of quasi additivity; moreover we study the behavior of these concepts in relation to subsets. 相似文献
980.
The Herrlich's problem from [8] whether there are nontrivial classes of topological spaces that are both almost reflective or injective and almost coreflective or projective, is investigated in a more general setting using cone and cocone modifications of the classes used in the problem. We look also at the problem for uniform spaces. Typical results: There is no nontrivial multiprojective and orthogonal class of topological spaces; There is a reflective class of uniform spaces that is almost coreflective in Unif.Work on this paper was initiated while the first author was a C.N.R. visitor of the University of L'Aquila. Partial financial assistence by Charles University Grant 349/1994 is also acknowledged. 相似文献