Self-assembly of Co/Pt stripes with current-induced domain wall motion towards 3D racetrack devices.

Modification of the magnetic properties under the induced strain and curvature is a promising avenue to build three-dimensional magnetic devices, based on the domain wall motion. So far, most of the studies with 3D magnetic structures were performed in the helixes and nanowires, mainly with stationary domain walls. In this study, we demonstrate the impact of 3D geometry, strain and curvature on the current-induced domain wall motion and spin-orbital torque efficiency in the heterostructure, realized via a self-assembly rolling technique on a polymeric platform.

Morphological features of Late Ordovician (Sandbian) bryozoans from the basin of Khrevitsa River (north-western Russia) and description of a new species of the genus Prophyllodictya Gorjunova, 1987.

Some Sandbian (Late Ordovician) bryozoans are here described from the Leningrad region, north-western Russia. The studied association is represented by eight species including one new cryptostome bryozoan Prophyllodictya khrevitsa n. sp.

Late Devonian-early Carboniferous bryozoans from Zhankurgan (Greater Karatau, Kazakhstan)-taxonomy and palaeobiogeographical implications.

Three bryozoan species Anomalotoechus sp., Pseudobatostomella sp. and Cyphotrypa sp.

Synthesis of SrF:Yb:Er ceramic precursor powder by co-precipitation from aqueous solution with different fluorinating media: NaF, KF and NHF.

The major challenge in optical ceramic technology is the quality of the starting precursor powder for pressing, which is a key element in the optical ceramic industry. One express and helpful technique for the estimation of powder quality is the estimation of the quantum yield of up-conversion luminescence; therefore precursor powders must exhibit high values of up-conversion luminescence efficiency. Single-phase solid solutions based on strontium fluoride doped with ytterbium and erbium were synthesised by co-precipitation from aqueous solutions using sodium fluoride, potassium fluoride and ammonium fluoride as fluorinating agents.

Study of synthesis temperature effect on-NaGdF: Yb, Er upconversion luminescence efficiency and decay time using maximum entropy method.

Upconversion materials have several advantages for many applications due to their great potential in converting infrared light to visible. For practical use, it is necessary to achieve high intensity of UC luminescence, so the studies of the optimal synthesis parameters for upconversion nanoparticles are still going on. In the present work, we analyzed the synthesis temperature effect on the efficiency and luminescence decay of-NaGdYbErF(15-25 nm) upconversion nanoparticles with hexagonal crystal structure synthesized by anhydrous solvothermal technique.

Temperature Sensing in the Short-Wave Infrared Spectral Region Using Core-Shell NaGdF:Yb, Ho, Er@NaYF Nanothermometers.

The short-wave infrared region (SWIR) is promising for deep-tissue visualization and temperature sensing due to higher penetration depth and reduced scattering of radiation. However, the strong quenching of luminescence in biological media and low thermal sensitivity of nanothermometers in this region are major drawbacks that limit their practical application. Nanoparticles doped with rare-earth ions are widely used as thermal sensors operating in the SWIR region through the luminescence intensity ratio (LIR) approach.

Hydrophobic up-conversion carboxylated nanocellulose/fluoride phosphor composite films modified with alkyl ketene dimer.

Hydrophobic up-conversion nanocomposite films have been developed based on TEMPO-oxidized cellulose nanofibrils (TOCNF) modified with alkyl ketene dimer (AKD) as a matrix and MF:Ho (M = Ca, Sr) as a phosphor. Fabrication of homogeneous, strong and translucent TOCNF/MF:Ho-AKD films with water contact angle of 123 ± 2° was accomplished with mild drying at 110 °C. These hydrophobic nanocomposite films demonstrated stable up-conversion luminescence in the visible spectral range upon excitation of the I level of Ho ions by laser irradiation at 1912 nm both under ambient conditions and in a humid atmosphere (92 ± 2% humidity).

Indium iodide single crystal: breakthrough material for infrared acousto-optics.

Measurements of the refractive indices and the full set of longitudinal acousto-optical figures of merit in an orthorhombic single-crystal indium iodide (InI) were carried out. The high acousto-optic characteristics ( up to 1100×10) and strong optical anisotropy (=0.47) make it possible to design various types of high-performance acousto-optic devices of the middle and far-infrared spectral range.

[Clinical characteristic of factors and tools influencing the effectiveness and safety of local anesthesia in dentistry].

Dental health is one of the most important signs of life quality and depends on the level of health care organization. Recently the clinical odontology is intensively developing, including local anesthesia where constant searching of effective remedies and methods of suppression and treatment of pain is carried out. At the same time carrying out adequate local anesthesia has important practical value that is to some extent bound to massive visits of the patients to the clinics.

Cryopreservation effects on a viable sperm sterlet (Acipenser ruthenus) subpopulation obtained by a Percoll density gradient method.

In many fish species, sperm cryopreservation has deleterious effects and leads to a significant decrease in spermatozoa viability. However, the effect of cryopreservation on sperm cells that survive this process and are still viable is not fully understood. The objective of this study was to compare the viability and proteomes of fresh and cryopreserved sterlet (Acipenser ruthenus) sperm samples before and after live-dead cell separation using Percoll density gradient centrifugation.

Sperm maturation in sturgeon (Actinopterygii, Acipenseriformes): A review.

The morphology of the reproductive system of acipenseriform fishes is quite different from that of teleostean species, but an associated unique physiological difference in male sturgeons was not discovered until recently; sperm of sturgeons passes through the kidneys then via Wolffian ducts into the environment rather that emptying directly through seminal ducts. The mixing of sperm with excretory products has been found to be a requisite for the capacity to be activated (maturation step) instead of being deleterious. In the current review we summarize results of studies performed in our laboratory on physiological processes involved in sturgeon sperm maturation, namely changes in: 1) ionic environment; 2) sensitivity of spermatozoa to calcium ions (Ca); 3) antioxidant enzymes and proteolytic activities; and 4) content in macroergic phosphates arising during this maturation process.

Is Geometric Frustration-Induced Disorder a Recipe for High Ionic Conductivity?

Ionic conductivity is ubiquitous to many industrially important applications such as fuel cells, batteries, sensors, and catalysis. Tunable conductivity in these systems is therefore key to their commercial viability. Here, we show that geometric frustration can be exploited as a vehicle for conductivity tuning.

Upconversion microparticles as time-resolved luminescent probes for multiphoton microscopy: desired signal extraction from the streaking effect.

The great interest in upconversion nanoparticles exists due to their high efficiency under multiphoton excitation. However, when these particles are used in scanning microscopy, the upconversion luminescence causes a streaking effect due to the long lifetime. This article describes a method of upconversion microparticle luminescence lifetime determination with help of modified Lucy–Richardson deconvolution of laser scanning microscope (LSM) image obtained under near-IR excitation using nondescanned detectors.

Lipid composition in common carp (Cyprinus carpio) sperm possessing different cryoresistance.

The present study examined the lipid composition of plasma membranes in carp sperm with different post-thaw motility. The approach adapted for carp sperm cryopreservation, which involves the selection of the most effective protocol for individual males by comparing two cryoprotective media, was applied to the cryopreservation procedure. Sperm motility prior to freezing was greater than 80% but decreased to 40% in one group and to 10% in another group following cryopreservation.

Quantification of adenosine triphosphate, adenosine diphosphate, and creatine phosphate in sterlet spermatozoa during maturation.

Sturgeon spermatozoa maturation during their passage through the kidney is a prerequisite for initiation of motility. Samples of sterlet () testicular sperm (TS) were matured in vitro by incubation in seminal fluid (SF) or in SF supplemented with carbonyl cyanide -chlorophenyl hydrazone (CCCP; a respiration uncoupling agent). Sperm was diluted in activation medium (AM) containing 10 m Tris-HCl buffer (pH 8.

Fast and reliable method of conductive carbon nanotube-probe fabrication for scanning probe microscopy.

We demonstrate the procedure of scanning probe microscopy (SPM) conductive probe fabrication with a single multi-walled carbon nanotube (MWNT) on a silicon cantilever pyramid. The nanotube bundle reliably attached to the metal-covered pyramid is formed using dielectrophoresis technique from the MWNT suspension. It is shown that the dimpled aluminum sample can be used both for shortening/modification of the nanotube bundle by applying pulse voltage between the probe and the sample and for controlling the probe shape via atomic force microscopy imaging the sample.

Motility and fertilization ability of sterlet Acipenser ruthenus testicular sperm after cryopreservation.

Sturgeon spermatozoa are immotile in the testis and acquire the potential for motility after contact with urine in Wolffian duct. The present study tested if in vitro incubation of testicular sperm in seminal fluid from Wolffian duct sperm leads to the acquisition of sperm fertilization ability. Sterlet sperm was taken from the testes, matured in vitro and cryopreserved.

Diode-pumped Er:CaF2 ceramic 2.7 μm tunable laser.

Spectroscopic and laser properties of a newly developed high optical quality Er:CaF2 hot-formed ceramic were investigated. Under pulsed 968 nm laser diode pumping, the mid-infrared (2.7 μm) radiation was obtained with a slope efficiency of 3%.

Rhenium ion beam for implantation into semiconductors.

At the ion source test bench in Institute for Theoretical and Experimental Physics the program of ion source development for semiconductor industry is in progress. In framework of the program the Metal Vapor Vacuum Arc ion source for germanium and rhenium ion beam generation was developed and investigated. It was shown that at special conditions of ion beam implantation it is possible to fabricate not only homogenous layers of rhenium silicides solid solutions but also clusters of this compound with properties of quantum dots.

Novel benzanthrone aminoderivatives for membrane studies.

The potential of novel benzanthrone aminoderivatives to trace the changes in physicochemical properties of lipid bilayer has been evaluated. Binding of the dyes to the lipid bilayers composed of zwitterionic phospholipid phosphatidylcholine (PC) and its mixtures with anionic phospholipid cardiolipin (CL) and cholesterol (Chol) was followed by significant quantum yield increase with small blue shift of emission maximum. Analysis of partition coefficients of the dyes under study showed that all aminobenzanthrones possess high lipid-associating ability.

Efficient laser based on CaF(2)-SrF(2)-YbF(3) nanoceramics.

CaF(2)-SrF(2)-YbF(3) fluoride ceramics of high optical quality was prepared, and its absorption, fluorescence, and laser oscillation properties were investigated. Oscillation slope efficiency that was only a few percent lower than that for a single crystal of similar composition was demonstrated under diode pumping.

Glasslike two-level systems in minimally disordered mixed crystals.

THz spectroscopy is used to identify a broad distribution of two-level systems, characteristic of glasses, in the substitutional monatomic mixed crystal systems, Ba(1-x)Ca(x)F(2) and Pb(1-x)Ca(x)F(2). In these minimally disordered systems, two-level behavior, which was not previously known to occur, begins at a specific CaF(2) concentration. The concentration dependence, successfully modeled using the statistics of the impurity distribution in the lattice, points to a collective dopant tunneling mechanism.

[Energy regulation of transmembrane potentials in liver cells during hypoxia].

The influence of oxygen tension on values of transmembrane potentials in rat liver cell was investigated. The membrane potential was assessed by the uptake TPP as was determined on the ion-selective electrode. Infusion of inhibitors oxidative phosphorylation and glycolysis to incubation medium caused depolarization on the mitochondrial, and, the plasma membranes of this cell.