Schwarz method justification of a coupling between finite elements and integral representation for Maxwell exterior problem

We are interested in the resolution of an exterior Maxwell problem in 3D using a coupling between finite elements and integral representation. This strategy is interpreted as a Schwarz method which suggests a preconditioner for Krylov solvers. Numerical results confirm the relevance of the resolution scheme.     

The magnitude of the minimal displacement vector for compositions and convex combinations of firmly nonexpansive mappings

Maximally monotone operators and firmly nonexpansive mappings play key roles in modern optimization and nonlinear analysis. Five years ago, it was shown that if finitely many firmly nonexpansive operators are all asymptotically regular (i.e., they have or “almost have” fixed points), then the same is true for compositions and convex combinations. In this paper, we derive bounds on the magnitude of the minimal displacement vectors of compositions and of convex combinations in terms of the displacement vectors of the underlying operators. Our results completely generalize earlier works. Moreover, we present various examples illustrating that our bounds are sharp.     

Dynamic Hydrogen-Bonded Zinc Adeninate Framework (ZAF) for Immobilization of Catalytic DNA

Effective immobilization and delivery of genetic materials is at the forefront of biological and medical research directed toward tackling scientific challenges such as gene therapy and cancer treatment. Herein we present a biologically inspired hydrogen-bonded zinc adeninate framework (ZAF) consisting of zinc adeninate macrocycles that self-assemble into a 3D framework through adenine-adenine interactions. ZAF can efficiently immobilize DNAzyme with full protection against enzyme degradation and physiological conditions until it is successfully delivered into the nucleus. As compared to zeolitic imidazolate frameworks (ZIFs), ZAFs are twofold more biocompatible with a significant loading efficiency of 96 %. Overall, our design paves the way for expanding functional hydrogen-bonding-based systems as potential platforms for the loading and delivery of biologics.     

Critical behavior and magnetic entropy change in the La0.6Sr0.4Mn0.8Fe0.1Cr0.1O3 perovskite

Critical behavior in the La_0.6Sr_0.4Mn_0.8Fe_0.1Cr_0.1O₃ ceramics was studied using magnetization methods. Results show that the paramagnetic–ferromagnetic transition is of second order. Based on the critical behavior analysis using the Banerjee criterion and the Kouvel–Fisher method, we find the critical exponents: β=0.395±0.010, γ=1.402±0.010, and δ=5.208±0.007, for which the magnetic interaction is satisfied within the three-dimensional Heisenberg model. Results indicate the presence of short-range interactions. The magnetic entropy change (−ΔS_M) reached maximum values of 1.75, 1.45, 1.15, 0.8 and 0.43 J Kg⁻¹ K⁻¹ under a magnetic field variation of 5, 4, 3, 2 and 1 T, respectively. Nevertheless, these (−ΔS_M) values are much low for any potential application at this moment. The nature of this phenomenon is discussed in relation to the characteristics of the magnetic phase transition and critical exponents.     

Coulomb dissociation of incident 16O at 4.5 GeV/c

Projectile multifragment breakup of ¹⁶O, ²C and ⁷Li at energies 3.0–4.5 A-GeV is studied by means of the Weizsäcker-Williams method. The fragmentation channels of the ¹⁶O projectile at 4.5 A-GeV are investigated and compared with that of ¹⁶O at 200 A-GeV. The events characterized by N _h=0 and the events due to both Coulomb and diffraction dissociation have been selected and analyzed as a function of impact parameter. Also, the dependence of the electromagnetic dissociation cross-section on incident energy and the charge of projectile and target is found.     

Quantitative Structure-Affinity Relationships of Dopamine D2 Receptor Antagonists: A Comparison between Orthopramides and 6-Methoxysalicylamides

A large series of orthopramides (= 2-methoxybenzamides), 6-methoxysalicylamides, and 2,6-dimethoxy-benzamides were examined for their affinity to the dopamine D₂ receptor. The binding data were correlated with physicochemical parameters and ¹³C-NMR chemical shifts using the cross-validated partial least-squares method and multiple linear regression analysis. The results quantitate the influence of electronic factors and lipophilicity to D₂ receptor binding. They also show that the N-[(1-ethylpyrroIidin-2-yl)methyl] and N-(1-benzylpiperidin-4-yl) side-chains affect the mode of binding of these compounds.     

Quality assurance of e-learning in developing countries

In this paper some of the aspects of implementing measures for quality assurance of e-learning in developing countries are discussed. Also the main problems of establishing quality assurance of e-learning are illustrated. The advantages of adopting international measures of quality assurance in those countries together with several recommendations for the future and our conclusion are then given.     

Global synchronization of fractional‐order and integer‐order N component reaction diffusion systems: Application to biochemical models

This study considers the problem of control and synchronization between fractional‐order and integer‐order, N‐components reaction‐diffusion systems with nonidentical coefficients and different nonlinear parts. The control scheme is designed using the Lyapunov direct method. The results are exemplified by two significant biochemical models, namely, the fractional‐order Lengyel‐Epstein model and the Gray‐Scott model. To illustrate the effectiveness of the proposed scheme, numerical simulations are performed in one and two space dimensions using Homotopy Analysis Method (HAM).