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The existing methods for monitoring the performance of multi-criteria fire detectors do not provide for verification of their characteristics in the conditions of transition from smoldering to flame burning. The aim of the work is the development of the research methods of the environmental parameters during the transition from smoldering (pyrolysis) to flame combustion for simulation a test fire while checking the quality of multi-criteria fire detectors.A technique to conduct research of environmental parameters under conditions of heating wood samples of different sizes to a temperature of selfignition and burning crumpled and smooth paper has been developed.Changes in the concentration of carbon monoxide, specific optical density, and scattering ability during the transition from smoldering (pyrolysis) to flame burning of prepared wood and crumpled paper were studied for the first time.It is shown that the controlled environmental parameters during the transition from smoldering pyrolysis to flame burning change together. Conclusion: the speed of growth of the scattering ability of smoke decreases by 2.4 times, the speed of increase in the specific optical density and concentration of carbon monoxide increases by 2 and 5.3 times (respec-tively), during the transition from pyrolysis to flame burning of wood.

We consider a system of semilinear parabolic equations ut = Δг + с1(x,t)vp, vt = Δv + c2(x,t)uq, (x,t) ∈ Ω × (0,+∞) with nonlinear nonlocal boundary conditions ∂u/∂η = ∫k1(x,y,t)um(y,t)dy, ∂v/∂η = ∫Ωk2(x,y,t)vn(y,t)dy, (x,t) ∈ ∂Ω × (0,+∞) and initial data u(x,0) = u0(x), v(x,0) = v0(x), x ∈ Ω, where p, q, m, n are positive constants, Ω is bounded domain in RN(N ≥ 1) with a smooth boundary ∂Ω, η is unit outward normal on ∂Ω. Nonnegative locally Hӧlder continuous functions ci(x,t),i = 1,2, are defined for x ∈ Ω, t ≥ 0; nonnegative continuous functions ki(x,y,t),i = 1,2 are defined for x ∈ ∂Ω, y ∈ Ω, t ≥ 0; nonnegative continuous functions u0(x),v0(x) are defined for x ∈ Ω and satisfy the conditions ∂u0(x)/∂η = ∫k1(x,y,0)um0(y)dy, ∂v0(x)/∂η = ∫Ωk2(x,y,0)vn0(y)dy for x ∈ ∂Ω. In the paper blow-up set of classical solutions is investigated. It is established that blow-up of the solutions can occur only on the boundary ∂Ω if max(p,q) ≤ 1, max(m,n)> 1 and under certain conditions for the coefficients ki(x,y,t),i = 1,2.

Extracellular vesicles (EVs) are promising agents for liquid biopsy—a non-invasive approach for the diagnosis of cancer and evaluation of therapy response. However, EV potential is limited by the lack of sufficiently sensitive, time-, and cost-efficient methods for their registration. This research aimed at developing a highly sensitive and easy-to-use immunochromatographic tool based on magnetic nanoparticles for EV quantification. The tool is demonstrated by detection of EVs isolated from cell culture supernatants and various body fluids using characteristic biomarkers, CD9 and CD81, and a tumor-associated marker—epithelial cell adhesion molecules. The detection limit of 3.7 × 105 EV/µL is one to two orders better than the most sensitive traditional lateral flow system and commercial ELISA kits. The detection specificity is ensured by an isotype control line on the test strip. The tool’s advantages are due to the spatial quantification of EV-bound magnetic nanolabels within the strip volume by an original electronic technique. The inexpensive tool, promising for liquid biopsy in daily clinical routines, can be extended to other relevant biomarkers.

Hybrid multimodal nanoparticles, applicable simultaneously to the noninvasive imaging and therapeutic treatment, are highly demanded for clinical use. Here, Fe-Au core-satellite nanoparticles prepared by the method of pulsed laser ablation in liquids were evaluated as dual magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents and as sensitizers for laser-induced hyperthermia of cancer cells. The biocompatibility of Fe-Au nanoparticles was improved by coating with polyacrylic acid, which provided excellent colloidal stability of nanoparticles with highly negative ζ-potential in water (−38 ± 7 mV) and retained hydrodynamic size (88 ± 20 nm) in a physiological environment. The ferromagnetic iron cores offered great contrast in MRI images with r2 = 11.8 ± 0.8 mM−1 s−1 (at 1 T), while Au satellites showed X-ray attenuation in CT. The intravenous injection of nanoparticles enabled clear tumor border visualization in mice. Plasmonic peak in the Fe-Au hybrids had a tail in the near-infrared region (NIR), allowing them to cause hyperthermia under 808 nm laser exposure. Under NIR irradiation Fe-Au particles provided 24.1 °C/W heating and an IC50 value below 32 µg/mL for three different cancer cell lines. Taken together, these results show that laser synthesized Fe-Au core-satellite nanoparticles are excellent theranostic agents with multimodal imaging and photothermal capabilities.

Express and highly sensitive immunoassays for the quantitative registration of cardiac troponin I (cTnI) are in high demand for early point-of-care differential diagnosis of acute myocardial infarction. The selection of antibodies that feature rapid and tight binding with antigens is crucial for immunoassay rate and sensitivity. A method is presented for the selection of the most promising clones for advanced immunoassays via simultaneous characterization of interaction kinetics of different monoclonal antibodies (mAb) using a direct label-free method of multiplex spectral correlation interferometry. mAb-cTnI interactions were real-time registered on an epoxy-modified microarray glass sensor chip that did not require activation. The covalent immobilization of mAb microdots on its surface provided versatility, convenience, and virtually unlimited multiplexing potential. The kinetics of tracer antibody interaction with the “cTnI—capture antibody” complex was characterized. Algorithms are shown for excluding mutual competition of the tracer/capture antibodies and selecting the optimal pairs for different assay formats. Using the selected mAbs, a lateral flow assay was developed for rapid quantitative cTnI determination based on electronic detection of functionalized magnetic nanoparticles applied as labels (detection limit—0.08 ng/mL, dynamic range > 3 orders). The method can be extended to other molecular biomarkers for high-throughput screening of mAbs and rational development of immunoassays.

The mathematical modeling of three-dimensional magnetic field of the suspended electromagnetic iron separator intended for the separation of ferromagnetic objects from bulk non-magnetic materials presents the complicated problem for developers of the magnetic systems of iron separators, because without the acceptance of considerable simplifying assumptions it cannot be taken to the calculation of plane-parallel magnetic field in a piecewise homogeneous medium. The magnetic field of iron separator differs in sharp heterogeneity in a pole gap and under pole tips. The modeling of such field using software packages of FE analysis (for example, ANSYS) requires additional confirmation of reliability of results of mathematical modeling of electromagnetic iron separator the experimental data got at their physical modeling. Based on this, the article describes a test stand and a research method of the three-dimensional magnetic field of the electromagnetic iron separator using measuring a vector-component of magnetic induction by teslameter with Hall effect sensor. Based on the processing of experimental data the visualization of the spatial distribution of the module and vector-components of magnetic induction and ponderomotive (magnetic) force in Excel are presented. Visualization results of the three-dimensional magnetic field distribution of the suspended electromagnetic iron separator taken on the test stand are compared with the calculation results of the magnetic field of the separator in Elcut 6.0 programme but allowing plane-parallel magnetic field.

Active targeting of nanoparticles toward tumors is one of the most rapidly developing topics in nanomedicine. Typically, this strategy involves the addition of cancer-targeting biomolecules to nanoparticles, and studies on this topic have mainly focused on the localization of such formulations in tumors. Here, the analysis of the factors determining efficient nanoparticle targeting and therapy, various parameters such as types of targeting molecules, nanoparticle type, size, zeta potential, dose, and the circulation time are given. In addition, the important aspects such as how active targeting of nanoparticles alters biodistribution and how non-specific organ uptake influences tumor accumulation of the targeted nanoformulations are discussed. The analysis reveals that an increase in tumor accumulation of targeted nanoparticles is accompanied by a decrease in their uptake by the spleen. There is no association between targeting-induced changes of nanoparticle concentrations in tumors and other organs. The correlation between uptake in tumors and depletion in the spleen is significant for mice with intact immune systems in contrast to nude mice. Noticeably, modulation of splenic and tumor accumulation depends on the targeting molecules and nanoparticle type. The median survival increases with the targeting-induced nanoparticle accumulation in tumors; moreover, combinatorial targeting of nanoparticle drugs demonstrates higher treatment efficiencies. Results of the comprehensive analysis show optimal strategies to enhance the efficiency of actively targeted nanoparticle-based medicines.

The following algorithm of action of measuring body of reserve protection is offered: continuously differences vectors currents of phases A and B, B and C, C and A in these and previous timepoints are defined, these differences are subtracted the friend from the friend, and then - and their differences. It is shown that it provides the demanded sensitivity to two-phase short zamykakniya behind low-power transformers branch. The blocking ensuring the correct functioning of protection in various modes are considered. The algorithm of logical part is presented. Difficulties of realization on static elements are noted and at bilateral food.

Nanoparticle-based technologies are rapidly expanding into many areas of biomedicine and molecular science. The unique ability of magnetic nanoparticles to respond to the magnetic field makes them especially attractive for a number of in vivo applications including magnetofection. The magnetofection principle consists of the accumulation and retention of magnetic nanoparticles carrying nucleic acids in the area of magnetic field application. The method is highly promising as a clinically efficient tool for gene delivery in vivo. However, the data on in vivo magnetofection are often only descriptive or poorly studied, insufficiently systematized, and sometimes even contradictory. Therefore, the aim of the review was to systematize and analyze the data that influence the in vivo magnetofection processes after the systemic injection of magnetic nanostructures. The main emphasis is placed on the structure and coating of the nanomagnetic vectors. The present problems and future trends of the method development are also considered.

The ever-increasing use of magnetic particle bioconjugates (MPB) in biosensors calls for methods of comprehensive characterization of their interaction with targets. Label-free optical sensors commonly used for studying inter-molecular interactions have limited potential for MPB because of their large size and multi-component non-transparent structure. We present an easy-to-use method that requires only three 20-min express measurements to determine the key parameters for selection of optimal MPB for a biosensor: kinetic and equilibrium characteristics, and a fraction of biomolecules on the MPB surface that are capable of active targeting. The method also provides a prognostic dependence of MPB targeting efficiency upon interaction duration and sample volume. These features are possible due to joining a magnetic lateral flow assay, a highly sensitive sensor for MPB detection by the magnetic particle quantification technique, and a novel mathematical model that explicitly describes the MPB-target interactions and does not comprise parameters to be fitted additionally. The method was demonstrated by experiments on MPB targeting of cardiac troponin I and staphylococcal enterotoxin B. The validation by an independent label-free technique of spectral-correlation interferometry showed good correlation between the results obtained by both methods. The presented method can be applied to other targets for faster development and selection of MPB for affinity sensors, analytical technologies, and realization of novel concepts of MPB-based biosensing in vivo.

Based on some theoretical and practical approaches, the main stages of the quality assessment of aluminum-based grain refining master alloys have been revealed. Methods for the quality improvement of Al-Ti and Al-Ti-B grain refiners have been described.

The paper presents results of the investigations on the influence of raw material mixture obtained from foundry waste products (waste foundry mixture, granulated cupola fumace slag) on technological, physical and mechanical properties of silicate materials.