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161.
Lavinia L. Ruta Ileana C. Farcasanu Mihaela Bacalum Mina Rileanu Arpad Mihai Rostas Constantin Daniliuc Mariana Carmen Chifiriuc Luminia Mruescu Marcela Popa Mihaela Badea Emilia Elena Iorgulescu Rodica Olar 《Molecules (Basel, Switzerland)》2021,26(22)
Novel complexes of type [Cu(N-N)(dmtp)2(OH2)](ClO4)2·dmtp ((1) N-N: 2,2′-bipyridine; (2) L: 1,10-phenantroline and dmtp: 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine) were designed in order to obtain biologically active compounds. Complexes were characterized as mononuclear species that crystallized in the space group P-1 of the triclinic system with a square pyramidal geometry around the copper (II). In addition to the antiproliferative effect on murine melanoma B16 cells, complex (1) exhibited low toxicity on normal BJ cells and did not affect membrane integrity. Complex (2) proved to be a more potent antimicrobial in comparison with (1), but both compounds were more active in comparison with dmtp—both against planktonic cells and biofilms. A stronger antimicrobial and antibiofilm effect was noticed against the Gram-positive strains, including methicillin-resistant Staphylococcus aureus (MRSA). Both electron paramagnetic resonance (EPR) and Saccharomyces cerevisiae studies indicated that the complexes were scavengers rather than reactive oxygen species promoters. Their DNA intercalating capacity was evidenced by modifications in both absorption and fluorescence spectra. Furthermore, both complexes exhibited nuclease-like activity, which increased in the presence of hydrogen peroxide. 相似文献
162.
The natural correspondence between bounded planar quadrature domains, in the terminology of Aharonov-Shapiro, and certain
square matrices with a distinguished cyclic vector is further exploited. Two different cubature formulas on quadrature domains,
that is the computation of the integral of a real polynomial, are presented. The minimal defining polynomial of a quadrature
domain is decomposed uniquely into a linear combination of moduli squares of complex polynomials. The geometry of a canonical
rational embedding of a quadrature domain into the projective complemnt of a real affine ball is also investigated. Explicit
computations on order-two quadrature domains illustrate the main results.
Paper partially supported by the National Science Foundation Grant DMS-95000954. 相似文献
163.
Giulia Treu Mihai Vornicescu 《Calculus of Variations and Partial Differential Equations》2000,11(3):307-319
We consider the following problems
where is a convex function, is an open bounded subset of is a closed convex subset of such that and and are suitable obstacles. We give conditions on the function {\it g} under which the two problems are equivalent.
Received March 24, 1999/ Accepted January 14, 2000 / Published online June 28, 2000 相似文献
164.
165.
166.
Paun Mihai 《Mathematische Annalen》1998,310(3):411-421
Sans résumé
Re?u le 7 Octobre 1996 相似文献
167.
Mihai Mih?ilescu 《Journal of Mathematical Analysis and Applications》2008,340(1):687-698
In this paper we are concerned with a new class of anisotropic quasilinear elliptic equations with a power-like variable reaction term. One of the main features of our work is that the differential operator involves partial derivatives with different variable exponents, so that the functional-analytic framework relies upon anisotropic Sobolev and Lebesgue spaces. Existence and nonexistence results are deeply influenced by the competition between the growth rates of the anisotropic coefficients. Our main results point out some striking phenomena related to the existence of a continuous spectrum in several distinct situations. 相似文献
168.
Madalina Barbaiani Cristina Bibire Jürgen Dassow Aidan Delaney Szilárd Fazekas Mihai Ionescu Guangwu Liu Atif Lodhi Benedek Nagy 《Journal of Applied Mathematics and Computing》2006,22(1-2):21-38
Programmed grammars, one of the most important and well investigated classes of grammars with context-free rules and a mechanism controlling the application of the rules, can be described by graphs. We investigate whether or not the restriction to special classes of graphs restricts the generative power of programmed grammars with erasing rules and without appearance checking, too. We obtain that Eulerian, Hamiltonian, planar and bipartite graphs and regular graphs of degree at least three are pr-universal in that sense that any language which can be generated by programmed grammars (with erasing rules and without appearance checking) can be obtained by programmed grammars where the underlying graph belongs to the given special class of graphs, whereas complete graphs, regular graphs of degree 2 and backbone graphs lead to proper subfamilies of the family of programmed languages. 相似文献
169.
Stephan Ramon Garcia Mihai Putinar 《Transactions of the American Mathematical Society》2006,358(3):1285-1315
We study a few classes of Hilbert space operators whose matrix representations are complex symmetric with respect to a preferred orthonormal basis. The existence of this additional symmetry has notable implications and, in particular, it explains from a unifying point of view some classical results. We explore applications of this symmetry to Jordan canonical models, self-adjoint extensions of symmetric operators, rank-one unitary perturbations of the compressed shift, Darlington synthesis and matrix-valued inner functions, and free bounded analytic interpolation in the disk.
170.
We examine the temperature fields of human enamel [Yu D, Fox JL, Hsu J, Lynn Powell G, Higuchi WI. Computer simulation of surface temperature profiles during CO2 laser irradiation of human enamel. Opt Eng 1993; 32(2)] during multi-modes CO2 laser irradiation. For this we use the integral transform method as well as direct and inverse Laplace transform [Oane M, Sporea D. Temperature profiles modeling in IR optical components during high power laser irradiation. Infrared Phys Technol 2001; 42(1): 31–40; Oane M, Sporea D. Study of heat transfer in IR optical components during CO2 laser irradiation. Proc SPIE 2001; 4430: 898–904; Oane M. Mathematical modeling of the thermal field distributions in solids under multiple laser irradiations. Proc SPIE 2003; 5227: 329–34; Oane M, Apostol I, Timcu A. Temperature field modeling in laser heated metals for laser cleaning of surfaces. Proc SPIE 2003; 5227: 323–8]. The enamel block is modeled as homogeneous cylinder in three dimensions. Results indicate that (i) the thermal field depends on multi-modes structure; (ii) heat transfer coefficient plays an important role in temperature distribution. 相似文献