The existence of a complete oxidative phosphorylation system (OXPHOS) supercomplex including both electron transport system and ATP synthases has long been assumed based on functional evidence. However, no structural confirmation of the docking between ATP synthase and proton pumps has been obtained. In this study, cryo-electron tomography was used to reveal the supramolecular architecture of the rat heart mitochondria cristae during ATP synthesis. Respirasome and ATP synthase structure in situ were determined using subtomogram averaging. The obtained reconstructions of the inner mitochondrial membrane demonstrated that rows of respiratory chain supercomplexes can dock with rows of ATP synthases forming oligomeric ordered clusters. These ordered clusters indicate a new type of OXPHOS structural organization. It should ensure the quickness, efficiency, and damage resistance of OXPHOS, providing a direct proton transfer from pumps to ATP synthase along the lateral pH gradient without energy dissipation.

Under severe or prolonged stress, bacteria produce a nonspecific DNA‐binding protein (Dps), which effectively protects DNA against damaging agents both in vitro and in vivo by forming intracellular biocrystals. The phenomenon of protective crystallization of DNA in living cells has been intensively investigated during the last two decades; however, the results of studies are somewhat contradictory, and up to now, there has been no direct determination of a Dps–DNA crystal structure. Here, we report the in vitro analysis of the vital process of Dps–DNA co‐crystallization using two complementary structural methods: synchrotron small‐angle X‐ray scattering in solution and cryo‐electron tomography. Importantly, for the first time, the DNA in the co‐crystals was visualized, and the lattice parameters of the crystalline Dps–DNA complex were determined.

Rapid increase of intracellular synthesis of specific histone-like Dps protein that binds DNA to protect the genome against deleterious factors leads to in cellulo crystallization—one of the most curious processes in the area of life science at the moment. However, the actual structure of the Dps–DNA co-crystals remained uncertain in the details for more than two decades. Cryo-electron tomography and small-angle X-ray scattering revealed polymorphous modifications of the co-crystals depending on the buffer parameters. Two different types of the Dps–DNA co-crystals are formed in vitro: triclinic and cubic. Three-dimensional reconstruction revealed DNA and Dps molecules in cubic co-crystals, and the unit cell parameters of cubic lattice were determined consistently by both methods.

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Absence of anomalous Nernst effect in spin Seebeck effect of Pt/YIG AIP Advances 6, 015018 (2016); 10.1063/1.4941340Dual resonant structure for energy harvesting from random vibration sources at low frequency AIP Advances 6, 015019 (2016) The results of a comprehensive study of magnetic, magneto-transport and structural properties of nonstoichiometric Mn x Si 1-x (x≈0.51-0.52) films grown by the Pulsed Laser Deposition (PLD) technique onto Al 2 O 3 (0001) single crystal substrates at T = 340 • C are present. A highlight of used PLD method is the non-conventional ("shadow") geometry with Kr as a scattering gas during the sample growth. It is found that the films exhibit high-temperature (HT) ferromagnetism (FM) with the Curie temperature T C ∼ 370 K accompanied by positive sign anomalous Hall effect (AHE); they also reveal the polycrystalline structure with unusual distribution of grains in size and shape. It is established that HT FM order is originated from the bottom interfacial self-organizing nanocrystalline layer. The upper layer adopted columnar structure with the lateral grain size ≥ 50 nm, possesses low temperature (LT) type of FM order with T c

We have designed sensors based on Ag nanoparticles synthesized in situ on the vaterite beads. In this article we demonstrate an approach to produce size controllable spherical and elliptical vaterite particles and discuss time-dependent in situ Ag nanoparticles synthesis and its potential effect on surface-enhanced Raman scattering. The time dependent silver reduction synthesis in inorganic porous particles allows to regulate the number and size of Ag nanoparticles. It is shown that the irregular surface and high porosity of vaterite particles and large amount (surface filling factor) of the Ag nanoparticles are the critical parameters to increase the SERS signal to 104 times. Such inorganic composites have a huge potential in medical applications; soon they provide an opportunity to study intracellular processes in vivo. The detailed characterization of the microstructure of these composites was studied by scanning and transmission electron microscopy, including 3D visualization and energy dispersive x-ray microanalysis.

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Multilayered SiOx/SiO2 and SiOxNy/SiO2 thin films were fabricated using different techniques and subsequently annealed at high temperatures (≥1100 °C) in order to form Si nanocrystals by means of the well-known superlattice approach. The thickness of the SiOx and SiOxNy layers was varied from 1.5 to 5 nm, while for the SiO2 layers it was fixed at 4 nm. Using transmission electron microscopy, we showed that the multilayered structure generally sustains the high temperature annealing for both types of films. However, for samples with ultrathin SiOx or SiOxNy layers a breakdown of the superlattice structure and a complete intermixing of layers were observed at high temperatures. On the contrary, annealing at lower temperature (900 °C) preserves the multilayered structure even of such samples. Theoretical calculations showed that the intermixing of SiOx/SiO2 and SiOxNy/SiO2 superlattices in the ultrathin layers thickness limit may be explained thermodynamically by the gain in the Gibbs free energy, which depends in turn on the annealing temperature.