Synthesis and Nanoscale Characterization of LiNbO3 Thin Films Deposited on Al2O3 Substrate by RF Magnetron Sputtering under Electric Field

LiNbO3 thin films were deposited on Al2O3 substrates by RF-magnetron sputtering with in-situ electric field to study the self-polarization effect. The films have been characterized crystallographically by x-ray diffraction, and morphologically by atomic force microscopy. The films contain crystallites of LiNbO3 with preferable orientation [012] along the normal to the Al2O3 substrate surface (012). Piezoresponse force microscopy was used to study vertical and lateral polarization direction in LiNbO3 thin films. The analysis of the histograms of vertical piezoresponse images allowed to reveal self-polarization effect in films. The local piezoelectric hysteresis performed on the nanometer scale indicates switching behavior of polarization for LiNbO3 thin film

Synthesis and Nanoscale Characterization of LiNbO3 Thin Films Deposited on Al2O3 Substrate by RF Magnetron Sputtering under Electric Field

LiNbO3 thin films were deposited on Al2O3 substrates by RF-magnetron sputtering with in-situ electric field to study the self-polarization effect. The films have been characterized crystallographically by x-ray diffraction, and morphologically by atomic force microscopy. The films contain crystallites of LiNbO3 with preferable orientation [012] along the normal to the Al2O3 substrate surface (012). Piezoresponse force microscopy was used to study vertical and lateral polarization direction in LiNbO3 thin films. The analysis of the histograms of vertical piezoresponse images allowed to reveal self-polarization effect in films. The local piezoelectric hysteresis performed on the nanometer scale indicates switching behavior of polarization for LiNbO3 thin film

Formation of Titanium Nanotubes on the Surface of Dental Implants

Abstract This study represents the results of a series of experiments about the formation of titanium dioxide nanotubes on the implants surfaces. Were investigated the obtained uniformity of surface coatings blank in dental implants and the surfaces morphology

Nanoporous Layers and the Peculiarities of Their Local Formation on a Silicon Wafer

This review presents the results of the local formation of nanostructured porous silicon (NPSi) on the surface of silicon wafers by anodic etching using a durite intermediate ring. The morphological and crystallographic features of NPSi structures formed on n-and p-type silicon with low and relatively high resistivity have also been investigated. The proposed scheme allows one to experiment with biological objects (for example, stem cells, neurons, and other objects) in a locally formed porous structure located in close proximity to the electronic periphery of sensor devices on a silicon wafer. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

3D in vitro platform produced by two-photon polymerization for the analysis of neural network formation and function

Zr-Si organic-inorganic scaffolds fabricated by a two-photon polymerization technique were used for the primary culture of mouse embryonic neural cells. We observed that dissociated hippocampal cells adhere to the scaffolds, produce neurites, elongate and differentiate into adult neurons. Neuronal outgrowth and synaptogenesis were confirmed by immunohistochemical staining with antibodies against βIII-Tubulin and synaptophysin. The formation of a functional neural network was assessed by the measurement of spontaneous activity using Ca2+ imaging of dissociated hippocampal cultures grown on Zr-Si scaffolds. The results of this study suggest that two-photon-induced polymerization of organic-inorganic hybrid biomaterials provides a robust model for 3D neuronal tissue engineering studies

Laser MICROSAMPLING of soil microbial community

Standard microorganism isolating technology applied for complex multiphase environmental samples such as soil or sediment needs pre-treatment steps to remove living cells from their mixed-phase microniche, by creating a liquid-phase sample. This process removes synergetic relationships, which help to maintain viability of yet-to-be-cultured and hard-to-culture bacteria. In this paper we demonstrate a high throughput Laser Micro-Sampling (LMS) technology for direct isolation of pure microbial cultures and microbial consortia from soil. This technology is based on laser printing of soil microparticles by focusing near-infrared laser pulses on specially prepared samples of a soil/gel mixture spread onto a gold-coated glass plate. Microsamples of soil are printed on glucose-peptone-yeast agar plates, to estimate the LMS process influence on functional and taxonomic microbial diversity, and on «Eco-log» sole carbon sources microplates, to investigate functional diversity by "metabolic fingerprinting". The obtained results are compared with traditionally treated soil samples. It was shown that LMS treatment leads to increasing of cultured biodiversity and modifies the functional diversity. The strain of rare genus Nonomuraea was isolated by LMS from complex natural environment without using media selective for this genus

Long-term neurological and behavioral results of biodegradable scaffold implantation in mice brain

The aim of the study was to assess the integral outcomes of implantation biocompatible scaffold as the carrier of neural stem cells in the reconstructive surgery of open traumatic brain injury (TBI) by parameters of neurological and cognitive status of the animals in the experiment. Materials and Methods. Adult male C57BL/6 mice were injured with open-skull weight-drop method. 3D hydrogel scaffold based on modified chitosan in complex with hyaluronic acid was transplanted into the lesion cavity 1 week after TBI. Using a variety of behavioral and cognitive tests (modified neurological severity scores (mNSS), open field test as well as novel object recognition and passive avoidance tests) the short-and long-term neurological and memory functions sequelae induced by TBI were assessed. Magnetic resonance imaging was used to visualize the injury site. Results. Significant functional recovery was observed on both the mNSS and open field tests in the scaffold transplantation group compared to the control TBI group. In addition, enhanced improvement of short and long-term memory functions was found 5 months post injury. Magnetic resonance imaging data revealed that the scaffold transplantation result in decreasing of the volume of injury area compared to control TBI group and preventing the disruption of the neural networks of the brain. Conclusion. Taken together, our findings indicated that transplantation of 3D biodegradable scaffold into injury cavity contributed to the preservation of volume in the damaged region in the first months after TBI which in turn led to a better functional recovery in the remote period

Long-term neurological and behavioral results of biodegradable scaffold implantation in mice brain

The aim of the study was to assess the integral outcomes of implantation biocompatible scaffold as the carrier of neural stem cells in the reconstructive surgery of open traumatic brain injury (TBI) by parameters of neurological and cognitive status of the animals in the experiment. Materials and Methods. Adult male C57BL/6 mice were injured with open-skull weight-drop method. 3D hydrogel scaffold based on modified chitosan in complex with hyaluronic acid was transplanted into the lesion cavity 1 week after TBI. Using a variety of behavioral and cognitive tests (modified neurological severity scores (mNSS), open field test as well as novel object recognition and passive avoidance tests) the short-and long-term neurological and memory functions sequelae induced by TBI were assessed. Magnetic resonance imaging was used to visualize the injury site. Results. Significant functional recovery was observed on both the mNSS and open field tests in the scaffold transplantation group compared to the control TBI group. In addition, enhanced improvement of short and long-term memory functions was found 5 months post injury. Magnetic resonance imaging data revealed that the scaffold transplantation result in decreasing of the volume of injury area compared to control TBI group and preventing the disruption of the neural networks of the brain. Conclusion. Taken together, our findings indicated that transplantation of 3D biodegradable scaffold into injury cavity contributed to the preservation of volume in the damaged region in the first months after TBI which in turn led to a better functional recovery in the remote period