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This study describes the synthesis of new pyromellitic diimide (PMDI) derivatives obtained in good yields from the reaction between pyromellitic dianhydride and aminobenzazoles reactive to proton-transfer in the excited state (ESIPT). In this investigation, a non-ESIPT PMDI was also prepared for comparison. These compounds presented absorption maxima in the ultraviolet region attributed to the allowed

In the present paper, the effect of glyoxal on the gel formation within the adhesive systems based on urea-formaldehyde (UF) resins is shown. A reduction of formaldehyde content in wood-based panels by decreasing the formaldehyde/urea molar ratio in the UF resins leads to increasing of the UF resin gel time, and impairing the qualitative characteristics of the UF-based wood materials. Glyoxal is shown to speed up the crosslinking of the macromolecules as well as significant reduction of gel time of adhesive composition. The first reason is the result of reaction between glyoxal and ammonium ion leading to protons releasing. Another reason is that glyoxal and its interaction products react with macromolecules of the UF resin forming a three-dimension cross-linked structure. The gel time and the pot life of the UF resin are measured by the oscillatory viscometer. Formation of the UF cross-linked resin structure with glyoxal and a curing catalyst (ammonium sulfate) is studied using dispersion Raman scattering spectroscopy. Particleboards (PB) are produced using different amount of glyoxal and formaldehyde/urea molar ratio in the UF resin. The properties are evaluated according to the European Standards and include density, internal bond, thickness swelling moisture content and formaldehyde content.

While good laboratory practice in a forensic lab minimises the chance of infection of laboratory personnel, in certain cases, possible contamination of pieces of evidence with highly contagious pathogens might call for additional precautions. The number of potential disinfection methods that might be suitable for forensic genetics are surprisingly limited. First and foremost, the ideal technique should not inhibit DNA amplification, it should be effective against a host of pathogens, and it should be applicable on porous surfaces. We examined ozone treatment on extracted DNA samples and mock casework samples. Ozone-treated and control specimens were amplified with Qiagen Investigator ESSplex SE QS kit. Detected allele counts were compared between the treated and untreated sample groups. Following disinfection, concentration of ozone-treated DNA was about half of the control samples, but full STR profiles were recovered. In the case of mock casework samples (disposable surgical masks), there was no significant difference (p = 0.513) between the detected allele counts of control and ozone-treated samples. Sampling location of surgical masks (earloop, nosepiece) showed a statistically significant difference (p = 0.011), though. Comparing the effect of contributors on STR profiling, a significant difference (p = 0.001) was observed, which could be explained with the differences between individuals including shedding capacity, head size or shape. According to our pilot study, ozone treatment does not encumber the routine forensic DNA analysis, the sampling position or the contributor affected the allele counts more than the ozone treatment.

Experimental research has been carried out of the processes occurring in a three-flow vortex tube operating in the humid air. Two types of swirling devices are investigated: single-pass spiral (snail) and multi-entry of five curved channels. An increase in the isentropic efficiency of a multi-entry swirling device by an average of 45% for a cold flow in the region μ = 0.10 … 0.8 in comparison with a snail one has been experimentally confirmed. Three positions of the dividing gap were investigated at a distance of 4, 5, and 6 mm from the nozzle inlet. The drying efficiency of a snail-type swirling device is 10–15% better, and moisture removal through the separator is 10–25% better in comparison with a multi-entry swirling device. The vortex velocity distribution profiles are determined numerically using the SST turbulence model. It was revealed that an increase in the vortex velocity in the area of the swirling device by 15% made it possible to obtain an increase in the isentropic efficiency by 50%. A hypothesis has been put forward describing the mechanisms that realize the effect of breaking of liquid particles inside a vortex tube, which can reduce the efficiency of liquid separation by up to 25%.

The structure of the electron current through an individual filament of a nanometer-sized virtual memristor consisting of a contact of a conductive atomic force microscope probe to an yttria stabilized zirconia (YSZ) thin film deposited on a conductive substrate is investigated. Usually, such investigation is performed by the analysis of the waveform of this current with the aim to extract the random telegraph noise (RTN). Here, we suggest a new indirect method, which is based on the measurement of the spectrum of the low-frequency flicker noise in this current without extracting the RTN, taking into account the geometrical parameters of the filament. We propose that the flicker noise is caused by the motion (drift/diffusion) of oxygen ions via oxygen vacancies within and around the filament. This allows us to estimate the root mean square magnitude i0 of the current jumps, which are caused by random jumps of oxygen ions, and the number M of these ions. This is fundamental for understanding the elementary mechanisms of electron current flowing through the filament and resistive switching in YSZ–based memristor devices.

Investigation results on heat transfer in low-Prandtl helium-xenon gas mixture and air, flowing in a small diameter tube, are presented. New experimental data on the heat transfer coefficient in the flow of helium-xenon mixture are obtained; results of numerical simulation are compared with the experimental data and known empirical correlations. Based on the simulation data it is shown that in a heated tube an increase in the Reynolds number due to an increase in the flow rate intensifies the heat transfer, and it may be due to the flow acceleration. It is shown that the high flow velocity and significant acceleration have a considerable effect on heat transfer in a tube, and the use of mean-mass stagnation temperatures as the determining one for generalization of data on heat transfer is insufficient. For the studied conditions, the known correlations give a significant error in determination of the heat transfer coefficient: the lower the Prandtl number and gas density, the higher the error.

The purpose of the present study was to investigate all the drowning-related cases in South-West Hungary between 2008 and 2012. It is a retrospective and descriptive study of 114 drowning-related deaths during that 5-year period. The investigation includes both unintentional and intentional drowning cases. We found that the most considerable risk factor of drowning in this area of Hungary is alcohol consumption, because in more than half of the cases the victims were under the influence of alcohol. We also concluded that more than two third of the cases included males. The cause of drowning in younger victims was mostly accident. In both genders subjects aged 50-70 had the highest risk of drowning in the period investigated. Seniors frequently committed suicide by drowning. Drowning deaths occurred in all types of water, mostly in lakes, rivers, canals and other types of catchment in the vicinity of victims' homes (most commonly in wells). This study might help to understand the circumstances and the causes leading to drowning and it may draw the attention to the possible preventive interventions.

Novel rationally-designed Syk-kinase inhibitor MT-SYK-03 demonstrated equal potency with R406 (active metabolite of Fostamatinib, a phase III clinical trial candidate) in cellular models of autoimmunity and cancer with EC50 values in sub-micromolar range, while MT-SYK-322 was less active.

The paper presents the results of experimental and calculated determinations of the operational characteristics of a gas-cumulative launching device of the type known as "Titov's accelerator". The parameters of the explosion products flow in this device, which depend on structural factors, were determined by the numerical simulation using a two-dimensional hydrodynamic code. Values of the static and dynamic pressure applied to the projectile at various phases of acceleration were calculated. Experimental conditions are shown in which 5.5-8 mm diameter steel and titanium projectiles were accelerated to velocities of 3-7.5 km/s with low probability of fracture. Ablation experienced by the projectile during acceleration was determined using the x-rayography. Ablation of titanium projectiles during acceleration can reach a half of their initial mass. This paper presents data on parameters of craters in simple targets and the influence of ablation of the projectiles on crater size and shape.

Hyperglycemia plays a critical role in the development and progression of diabetic neuropathy. One of the mechanisms by which hyperglycemia causes neural degeneration is via the increased oxidative stress that accompanies diabetes. Metabolic and oxidative insults often cause rapid changes in glial cells. Key indicators of this response are increased synthesis of glial fibrillary acidic protein (GFAP) and S100B, both astrocytic markers. In the present study, we examined glial reactivity in hippocampus, cortex, and cerebellum of streptozotocin (STZ)-induced diabetic rats by determining the expression of GFAP and S-100B and we evaluated the effect of melatonin on the glial response. Western blot measurement of contents in brain regions after 6 weeks of STZ-induced diabetes indicated significant increases in these constituents compared with those in nondiabetic controls. Administration of melatonin prevented the upregulation of GFAP in all brain regions of diabetic rats. Using GFAP immunohistochemistry, we observed an increase in GFAP immunostaining in the hippocampus of STZ-diabetic rats relative to levels in the control brains. Treatment with melatonin resulted in an obvious reduction of GFAP-immunoreactive astrocytes in hippocampus. Like GFAP, S100B levels also were increased in all three brain areas of diabetic rats, an effect also reduced by melatonin treatment. Finally, the levels of lipid peroxidation products were elevated as a consequence of diabetes, with this change also being prevented by melatonin. These results suggest that diabetes causes increased glial reactivity possibly due to elevated oxidative stress, and administration of melatonin represents an achievable adjunct therapy for preventing gliosis.

Neuroprotective effects of melatonin against free radical damage have been studied extensively. Thinner containing 60-70% toluene is a neurotoxic mixture which is widely used as an aromatic industrial solvent. This product has been shown to cause functional and structural changes in the central nervous system. Toluene generates reactive oxygen species (ROS) and the toxic effects relating to these reactants. In the present study we investigated glial reactivity in hippocampus, cortex and cerebellum and the expression of glial fibrillary acidic protein (GFAP) after exposure of rats to toluene vapor (3000 ppm) for 45 days. We also examined the protective effects of melatonin against gliosis. Western blots demonstrated a marked elevation in total GFAP, a specific marker for astrocytes, by thinner fume inhalation in the hippocampus (P

Glial interactions with neurones play vital roles during the ontogeny of the nervous system and in the adult brain. Physical and metabolic insults cause rapid changes in the glial cells and this phenomenon is called reactive gliosis. One of the important events during astrocyte differentiation is the increased expression of glial markers, glial fibrillary acidic protein (GFAP) and S-100B protein. Diabetes mellitus is the most common serious metabolic disorder, which is characterised by functional and structural changes in the peripheral as well as in the central nervous system. In the present study, we aimed to investigate glial reactivity in hippocampus, cortex and cerebellum of streptozotocin-induced diabetic rats by determining the expression of GFAP and S-100B and also to examine the protective effects of vitamin E against gliosis. Western blotting showed increases in total and degraded GFAP content and S-100B protein expression in brain tissues of diabetic rats compared with those of controls. In addition, there was a significant increase in lipid peroxidation in these brain regions of diabetic rats. Both glial markers and lipid peroxidation levels were reversed by vitamin E administration. These findings indicate that streptozotocin-induced diabetes alters degradation and production of GFAP and S-100B, which are markers of reactive astrocytosis. Thus, determination of GFAP and S-100B may provide a relevant marker in the central nervous system for studying neurodegenerative changes in experimental diabetes mellitus. This study also suggests that the gliosis that occurs in diabetes mellitus is mediated, at least indirectly, by free radical formation and antioxidants may prevent reactive gliosis possibly by reducing damaging effects of reactive oxygen species in the central nervous system.

A set of novel fragment-like catechol derivatives were identified as EphA2 inhibitors and were further profiled against a panel of 19 tyrosine kinases. In addition to EphA2, the recovered hits were active against EGFR, FGFR1, FGFR2, Abl and PDGFR-a, and according to molecular modelling studies catechol moiety was capable of forming two or more correlated hydrogen bonds with the kinase hinge region, suggesting prospects of its further optimization as an EphA2 inhibitor.

The development of heat storage (HS) devices for pre-heating internal-combustion engines at start-up is presented as an extremely urgent problem. The absence of warm garages and the above-average depreciation of automotive machinery, especially urban buses, force maintenance organisations to search for new ways to facilitate engine start-up in cold periods. In this work, a thermal accumulator (HS) working on the effects of absorption and rejection of heat energy at the solid-liquid phase-change of the heat storage substance is discussed. In the theoretical part, a numerical method for calculating heat storage and the characteristics of heat storage devices is described. The experimental part describes the laboratory installation simulating conditions for the working of the HS device and presents the results of laboratory experiments. Data on full-scale tests of pre-heating devices for starting carburettor engines and an analysis of data received are given.

The enantioselectivity of the Diels–Alder reaction between (E)-3-(4-nitrophenyl)-1-(pyridin-3-yl)prop-2-en-1-one and cyclopenta-1,3-diene in the chiral ionic liquids 3-butyl-1-methylimidazolium (S)-camphorsulfonate and (S)-1-methyl-3-(pyrrolidin-2-ylmethyl)- imidazolium tosylate or upon chiral promotion with chiral oxazaborolidine was modeled by molecular and quantum mechanics and then experimentally studied; computations were in good agreement with the experimental data, resulting in no stereoselectivity with a chiral ionic liquid used as a co-solvent and prominent stereoselectivity upon chiral promotion.

The probabilistic description and analysis of the response of time-invariant nonlinear dynamic systems driven by stochastic processes is usually treated by means of evaluation of statistical moments and cumulants of the response. The background of these methods is the Fokker-Planck-Kolmogorov (FPK) equation for a probability density function or the Pugachev equation for a characteristic function, respectively. The exact solutions of these equations are obtained only for isolated cases. For engineering probabilistic analysis of a complex nonlinear systems, different mixed (hybrid) methods in these cases are used. In this study a ‘benchmark’ solution is obtained on the basis of the FPK equation in conjunction with the method of statistical moments for nonlinear mechanical system with colored parametric excitations. In Part 1 (this part), an exact solution of FPK equation on the basis of asymptotic analysis of nonlinear dynamic behavior of parametric excitation system is discussed. In Parts 2 and 3, applications of this method to stochasticity and stability analysis of nonlinear time-variant systems are considered. A comparison with the accuracy of different statistical methods is discussed. In Parts 4 and 5, a method of stochastic analysis of relativistic and quantum dynamic systems is described on the basis of a generalized stochastic Hamilton-Jacobi equations on a differential manifold as Riemanian geometry. This involves the task of relativistic navigation and dissipative quantum models of a nonlinear parametric oscillator in the presence of stochastic excitations on a differential manifold with different metric tensors of the space-time continuum.

In this, the second of a two part paper, the applications of the Fokker-Planck-Kolmogorov (FPK) method to stochastic analysis of time-variant nonlinear systems are considered. A new class of dynamic systems with stochastic nonlinearity and jump parametric exitations is introduced. The comparison of accuracy of different statistical methods such as statistical linearization is discussed.

The transported entropy and the Thomson coefficient for charge conducting ions are needed to predict reversible heat effects in batteries. Transported entropies and Thomson coefficients have been calculated from Seebeck coefficients of the cell Fe&, T1) 1 Me 1 8" alumina 1 Me 1 Fe@, 7") for Na and K (Me). The result is S&+ = 56 f 3 JK-' mol-' at SOOK, with a Thomson coefficient rN.+ = 30 f 2 J K-' mol-' in the temperature interval 333-773 K. The transported entropy of Na+ did not change by freezing Na at 370. The results for K+ are identical to those of Na+, within the accuracy of the experiments. The Thomson coefficient derived from measurements at different values of T, was consistent with the observed variation in emfwith AT for a given Tl. The reversible heat changes at the electrodes have been calculated for sodium sulphur and potassium sulphur batteries. During discharge both bat- teries produce a net reversible heat, the production always being largest at the alkali metal anode. At the cathode, the heat effect becomes relatively small when the composition of Na and S is within the one phase region. A change in composition from the one phase to the two phase region is expected to lead to changes in local temperature gradients. The systems were described by the electric work method, a method which has practical advantages compared to other electrochemical methods.

In this paper described and substantiated is the structural scheme of the algorithmic support for the control of the process of obtaining large-size crystals by the Czochralski method. Information-measuring system is considered as a unified firmware complex in which the functions of these algorithmic procedures are combined in optimum way.

Molecular modeling and subsequent synthesis of novel Syk-kinase inhibitors, 7H-pyrrolo[2,3-d]pyrimidine and 1,3,5-triazine derivatives, have been carried out. The best of the obtained compounds demonstrated to inhibit Syk-kinase activity at IC50 = 230±10 nM