Applicability of point dipoles approximation to all-dielectric metamaterials

All-dielectric metamaterials consisting of high-dielectric inclusions in a low-dielectric matrix are considered as a low-loss alternative to resonant metal-based metamaterials. In this contribution we investigate the applicability of the point electric and magnetic dipoles approximation to dielectric meta-atoms on the example of a dielectric ring metamaterial. Despite the large electrical size of high-dielectric meta-atoms, the dipole approximation allows for accurate prediction of the metamaterials properties for the rings with diameters up to ~0.8 of the lattice constant. The results provide important guidelines for design and optimization of all-dielectric metamaterials.Comment: 10 pages, 5 fugures, submitted to Physical Review

Morpho-functional basis of endothelial dysfunction in diabetes mellitus

The diabetes mellitus (DM) inevitably progresses and leads to complications, among which the main place is occupied by micro- and macroangiopathies. The presence of endothelial damage in DM can be established even before macroscopically significant damage to the vessel. At the same time, there is no summary ED characteristic for diabetes. The aim of the study is to make a comprehensive evaluation of ED in DM -1 and DM-2 types.Materials and methods of research. 60 persons, including 53 DM type 1 and type 2, with a severe course (state of decompensation) participated in the present study. We used the method of estimating ED by the number of circulating desquamation endothelial cells (CECs) at the stages of decomposition with simultaneous determination of NO2- and NO3- metabolites of nitric oxide.Results and discussion. In patients with diabetes, the level of CECs increased in 3-5 times and ranged from 1800 to 11,200 cells / ml. The average amount of CECs in patients with diabetes was 3358.5 ± 366.3 cells / ml.Conclusions: Endothelium is involved in the pathological process at DM. This is evidenced by a significant increase in CECs in the blood plasma. The use of this method allows to detect ED before clinically considerable vascular impairment and reflects the severity of the course and duration of DM

Long-distance entanglement and quantum teleportation in XX spin chains

Isotropic XX models of one-dimensional spin-1/2 chains are investigated with the aim to elucidate the formal structure and the physical properties that allow these systems to act as channels for long-distance, high-fidelity quantum teleportation. We introduce two types of models: I) open, dimerized XX chains, and II) open XX chains with small end bonds. For both models we obtain the exact expressions for the end-to-end correlations and the scaling of the energy gap with the length of the chain. We determine the end-to-end concurrence and show that model I) supports true long-distance entanglement at zero temperature, while model II) supports {\it ``quasi long-distance''} entanglement that slowly falls off with the size of the chain. Due to the different scalings of the gaps, respectively exponential for model I) and algebraic in model II), we demonstrate that the latter allows for efficient qubit teleportation with high fidelity in sufficiently long chains even at moderately low temperatures.Comment: 9 pages, 6 figure

The conditions for the organization of the creative activity of children, parents and teacher, ensuring the development of the creative potential of preschool children in pre-school educational organization

В данной статье автором раскрыты условия, необходимые для развития творческого потенциала детей в ходе организации сотворческой деятельности всех участников образовательного процесса – детей, родителей и педагогов в условиях дошкольной образовательной организации.In this article the author discloses the conditions necessary for the development of creative potential of children in the process of organizing the co-creative activity of all participants of educational process – children, parents and teachers in the conditions of a preschool educational organization

Conditioned reflex activity of rats at later periods after the end of flight aboard the Kosmos-605 biosatellite

The aftereffects of spaceflight on the higher nervous activity of rats were studied. A five lane maze with a feeding terminal was used to check such factors as transfer of experience, the habit and speed of reaching the goal in the maze, long term memory, and the dynamics of errors. During the 3rd-7th postflight week, functional disturbances in the rat HNA were manifested in the deterioration of the capacity for the transfer of experience and for locating the feeding compartment in the maze, thus indicating a general decrease of work capacity. The increased number of errors and failures pointed to exhaustion of higher nervous processes and to the weakened functional activity of the brain

One-dimensional structures behind twisted and untwisted superYang-Mills theory

We give a one-dimensional interpretation of the four-dimensional twisted N=1 superYang-Mills theory on a Kaehler manifold by performing an appropriate dimensional reduction. We prove the existence of a 6-generator superalgebra, which does not possess any invariant Lagrangian but contains two different subalgebras that determine the twisted and untwisted formulations of the N=1 superYang-Mills theory.Comment: 12 pages. Final version to appear in Lett. Math. Phys. with improved notation and misprints correcte

Hierarchical meta-porous materials as sound absorbers

The absorption of sound has great significance in many scientific and engineering applications, from room acoustics to noise mitigation. In this context, porous materials have emerged as a viable solution towards high absorption performance and lightweight designs. However, their performance is somehow limited in the low frequency regime. Inspired by the concept of recursive patterns over multiple length scales typical of many natural materials, here, we propose a hierarchical organization of multilayered porous media and investigate their performance in terms of sound absorption. Two types of designs are investigated: a hierarchical periodic and a hierarchical gradient. In both cases it is found that the introduction of multiple levels of hierarchy allows to simultaneously (i) increase the level of absorption compared to the corresponding bulk block of porous material, along with (ii) a reduction of the quantity of porous material required. Both the cases of normal and oblique incidences are examined. The methodological approach is based on the transfer matrix method, optimization algorithms (metaheuristic Greedy Randomized Adaptive Search Procedure), and finite element calculations. An excellent agreement is found between the analytical and the numerical simulations