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Recent advances in DNA nanotechnology allow for the assembly of nanocomponents with nanoscale precision, leading to the emergence of DNA-based material fabrication approaches. Yet, transferring these nano- and micron-scale structural arrangements to the macroscale morphologies remains a challenge, which limits the development of materials and devices based on DNA nanotechnology. Here, we demonstrate a materials fabrication approach that combines DNA-programmable assembly with actively driven processes controlled by acoustic fields. This combination provides a prescribed nanoscale order, as dictated by equilibrium assembly through DNA-encoded interactions, and field-shaped macroscale morphology, as regulated by out-of-equilibrium materials formation through specific acoustic stimulation. Using optical and electron microscopy imaging and x-ray scattering, we further revealed the nucleation processes, domain fusion, and crystal growth under different acoustically stimulated conditions. The developed approach provides a pathway for the fabrication of complexly shaped macroscale morphologies for DNA-programmable nanomaterials by controlling spatiotemporal characteristics of the acoustic fields. DNA nanotechnology is useful in preparing nano- and meso-components, but transfer to macroscale arrangements is challenging. Here, the authors report an assembly approach combining DNA programmable assembly with process controlled by acoustic fields to prepare macroscale morphologies.

The origin and nature of extreme energy cosmic rays (EECRs), which have energies above the 5 ⋅ 10 19 eV —the Greisen-Zatsepin-Kuzmin (GZK) energy limit, is one of the most interesting and complicated problems in modern cosmic-ray physics. Existing ground-based detectors have helped to obtain remarkable results in studying cosmic rays before and after the GZK limit, but have also produced some contradictions in our understanding of cosmic ray mass composition. Moreover, each of these detectors covers only a part of the celestial sphere, which poses problems for studying the arrival directions of EECRs and identifying their sources. As a new generation of EECR space detectors, TUS (Tracking Ultraviolet Set-up), KLYPVE and JEM-EUSO, are intended to study the most energetic cosmic-ray particles, providing larger, uniform exposures of the entire celestial sphere. The TUS detector, launched on board the Lomonosov satellite on April 28, 2016 from Vostochny Cosmodrome in Russia, is the first of these. It employs a single-mirror optical system and a photomultiplier tube matrix as a photo-detector and will test the fluorescent method of measuring EECRs from space. Utilizing the Earth’s atmosphere as a huge calorimeter, it is expected to detect EECRs with energies above 10 20 eV . It will also be able to register slower atmospheric transient events: atmospheric fluorescence in electrical discharges of various types including precipitating electrons escaping the magnetosphere and from the radiation of meteors passing through the atmosphere. We describe the design of the TUS detector and present results of different ground-based tests and simulations.

This article presents the results of the design and analysis of a radio-frequency switch made using microelectromechanical systems technology. The device is the capacitive switch with a hybrid type of contact, in which the movable electrode of the structure – the metal membrane is part of the microwave signal line of the coplanar waveguide. The switch design is characterized by a high capacitance ratio and low contact resistance. The zig-zag elastic suspension is used to reduce the value of the pull-down voltage – 2 V and the switching time ∼ 7 us. The central resonant frequency of the switch is 3.8 GHz. In this case, in the open state, the value of the insertion loss is not more than -0.2 dB and the isolation value in the close state is not less than -55 dB. The effective frequency range is the S-band, as well as the C-, X- and Ku-band, in which the isolation value is at least -30 dB. The presented inline RF MEMS switch is suitable for use in various types of ground and satellite communications, in particular for devices and systems of 5G mobile networks.

Quantum point contacts with a short (100-nm) channel in a high-mobility two-dimensional electron gas of GaAs/Al(Ga)As heterostructures and a short-channel p -type field-effect transistor in a silicon-on-insulator structure were fabricated and studied experimentally and by modeling at the Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, in order to study the response of the samples to weak irradiation by an electromagnetic field with a frequency of ~2 GHz. This response in the tunneling mode at a temperature of 4.2 K turned out to be giant and was observed against the background of features caused by impurity disorder.

The article solves the problem of the stress state of a heavy half-plane, weakened by a semicircular recess (modeling a foundation pit) and under the influence of a uniformly distributed load (modeling weight from a nearby building). The solution was obtained in a closed form. Visual calculations results in the form of diagrams and isolines of the total voltage are presented. The resulting solution made it possible to consider two practical problems. In the first statement, to assess the pit parameters' influence on the components of the additional voltage in the corner zone of the distributed load. In the second statement, to assess the distance influence from the pit to the load on the additional voltage components. The analysis of the obtained solutions is carried out. The quantitative character of the change in the additional stress components, on which the dimensions of the influence zone of the construction pit and the existing buildings foundations' deformation is of particular practical interest.

Micromechanical linear acceleration sensors are widely used in modern inertial orientation and navigation systems of technical equipment used in industry. The paper presents the developed design of MEMS linear acceleration sensor with three sensitivity axes, modal and static analysis is performed, design parameters are found that ensure equality of natural frequencies along the sensitivity axes, and experimental samples are created and studied.

This article describes in detail the design of a shunt capacitive RF MEMS switch for Ka-frequency band, as well as the design of a single-pole-double-directional RF MEMS switch made on its basis. An electrostatic and electromagnetic analysis was performed using the MATLAB and ANSYS HFSS software package. The switch uses a 1.52 V actuation voltage and 1.3 μs of switching time to move the membrane from the up state to the down state. The operating frequency range of this switch is between 24-34 GHz with isolation of -53 dB at 29 GHz and reflection loss of -0.25 dB for this frequency range. The design of the switch is made on a GaAs substrate with a thickness of 525 μm with a double-sided insulating layer of silicon oxide with a thickness of 2 μm.

The results of the TUS experiment on search and study ultra high-energy cosmic rays with energies E > 70 EeV are analyzed. The TUS detector registered several unusual events of the unclear origin. The analysis of not similar to EAS and unique anomalous events is the subject of the study presented in this paper.

The aim of this study was to study the effect of metformin (Met) on the formation of the conditional passive avoidance skills, markers of neurogenesis and oxidative stress in the brain of rats with acute intracerebral hemorrhage (ICH) in the setting of streptozotocin-nicotinamide-induced diabetes. Type 2 diabetes mellitus (T2DM) was induced in rats via the intraperitoneal injection of streptozotocin (STZ) and nicotinamide (NA), ICH – by microinjection of bacterial collagenase into the striatum. Rats were randomly divided into four groups: 1 – intact animals (n=8), 2 – T2DM (n=9); 3 – T2DM+ICH (n=7); 4 – T2DM+ICH+Met (n=7). The passive avoidance test was used to evaluate behavioural activity. Advanced oxidation protein products (AOPP) and lactate were measured by spectrophotometry, advanced glycation end products (AGEs) by quantitative fluorescence, level of 8-hydroxy-2-deoxyguanosine (8-OHdG) was assessed by enzyme-linked immunosorbent assay (ELISA). Histopathological examination was performed using general histological staining techniques and immunohistochemical methods for assessment of expression of endothelial NO-synthase (eNOS), Growth Associated Protein 43 (GAP43), Hypoxia-inducible factor 1-alpha (HIF-1α), neural cadherine (N-cadherine) and vascular endothelial cadherine (VE-cadherine). In this study, metformin had nootropic (anti-amnestic) activity and decreased oxidative stress markers (AGEs, AOPPs and 8-OHdG) levels by 29.1% (p<0.001), 24.9% (p<0.015) and 29.3% (p<0.05) respectively, which indicates its positive impact on the course of free radical oxidation reactions intensified by both diabetes and intracerebral hemorrhage. The study provides additional information on neuroprotective properties of metformin and the emphasizes possibility of using metformin in diabetic patients at risk of hemorrhagic stroke. Considering the increase in VE-cadherin expression by the drug, it is possible to predict its positive effect on the function of blood-brain barrier. This study may serve as a reference for the feasibility of studying the clinical efficacy of metformin under these conditions.

This theses the linear acceleration sensor design with three axis of sensitivity is researched. Parameterized geometry and finite element model for modal analysis are developed in the ANSYS program. Behavioral description of the study design is developed with language VHDL-AMS to simulate the sensor operation under the influence of linear acceleration along three axis of sensitivity. On the basis of research results three-axis device sensitivity, cross-sensitivity, duration transients are specified. As part of the work the experimental sensor prototypes are fabricated.