The development of means of the prevention and treatment of age-related neurodegenerative diseases, as well as geroprotectors, among other things, is based on the inflammatory and free radical ...theories of aging. In this context, we studied the effect of sodium monophenol 3-(3’-
tert
-butyl-4’-hydroxyphenyl)propyl thiosulfonate (TS-13) on the behavioral and locomotor activity of C57BL/6 mice in modeling Parkinson’s disease by MPTP neurotoxin injection. TS-13 administration significantly improved orientation and exploratory activity and emotional response of the animals in the open field test, but did not affect the increase in anxiety caused by MPTP injection. Long-term (6 months) TS-13 administration did not suppress spontaneous motor activity in BALB/c mice and slightly increased their exploratory activity.
Thermally-induced microstructure and property alteration of nano-multilayer (NML) coatings are of principal importance for industrial applications. The phenomenon of surface outflow of confined metal ...is highly promising for the development of NML-based brazing fillers for joining technology. Annealing conditions, such as temperature and atmosphere, are the principal factors defining the brazing filler outflow characteristics besides the NML design. The present study addresses the microstructure evolution of Ag/AlN NMLs during thermal treatment in various atmospheres (Ar, air, vacuum). The mechanisms of the NML bulk microstructure modification do not change with the annealing atmosphere. Channels in the NML volume are formed at each annealing atmosphere by grain boundary grooving, which act as pathways for Ag atoms transport to the NML surface, causing metal outflow. However, a significant effect of the atmosphere on the metal outflow and shape of the particles formed was observed. Annealing in an inert atmosphere and vacuum results in a moderate surface outflow of Ag atoms. On the contrary, heat treatment in air results in a chemical interaction of nanolayers with oxygen, substantially intensifying the outflow. This interaction is rationalized by considering the surface energies of Ag/AlN and Ag/Al2O3 interfaces, where the latter are formed upon annealing. Based on grooving angles, the upper bound Ag(111)/AlN(0001) interface energy estimate of 0.54 J/m2 at 650 °C was derived, which is significantly lower than the average magnitude of Ag/Al2O3 interface energy (~ 2 J/m2 for crystalline phases). Besides, the annealing atmosphere has an impact on the shape (elongated whiskers, bulk faceted crystals) of Ag particles formed on the NML surface by modifying silver surface energies.
The proper choice of a heat treatment atmosphere provides an innovative pathway for controlling the Ag surface outflow in Ag/AlN NMLs for novel low-temperature joining applications.
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•Annealing in air results in a larger Ag outflow than annealing in Ar or vacuum•At each annealing atmosphere, channels in the nano-multilayer volume are formed•The annealing atmosphere affects the shape of Ag particles formed on the surface•Chemical driving forces and stress relaxation are at the basis of Ag outflow•The estimate of Ag(111)/AlN(0001) interface energy at 650 °C is 0.54 J/m2
Co3Ge2O5(OH)4 relates to a specific group of 1:1 layered compounds with an ability to form either platy or tubular particles depending on chemical composition. Despite successful synthesis and ...perspective application, there is a lack of information on its crystal structure and magnetic properties, granted by Co ions. Co3Ge2O5(OH)4 phyllogermanate nanoparticles have been obtained using a hydrothermal method and characterised using powder X-ray diffraction and magnetisation measurements. Triclinic symmetry with a 1:P1 space group has been established. The unit cell contains three layers perpendicular to the c crystallographic direction, with 7.6 Å spacing and −b/3 shift of the middle layer. At a low magnetic field of 100 Oe the compound undergoes a magnetic transition at TN=5.2 K. The field of 9 T is not sufficient to take the sample to a magnetically saturated state with an asymptotic magnetic moment of 2.43 μB/Co2+. The estimations of the intralayer and interlayer exchange constants give values of J1/kB=2.75 K and J2/kB=0.25 K, respectively.
•Divalent phyllogermanate of cobalt was obtained for the first time by hydrothermal method.•Compound has hexagonal plates morphology and tends to be spliced along one direction.•The valence state of cobalt in the compound was clarified by the BVS method.•The magnetic subsystem parameters TN, χ0, θ, C, μeff, Hex were obtained.
On mouse neuroblastoma (Neuro-2a) and human glioblastoma (U-87 MG) cell lines, we studied the effect of inducers and inhibitors of redox-sensitive signaling system of the antioxidant-responsive ...element Keap1/Nrf2/ARE on the main processes that determine nerve cell viability and vital activity (proliferative activity, apoptosis, autophagy, and activation of the Keap1/Nrf2/ARE system). Inhibitors of the Keap1/Nrf2/ARE system stimulate apoptosis more pronouncedly than inducers, have a weaker effect on autophagy, and do not change the nuclear to cytoplasmic Nrf2 ratio. In general, the revealed effects testify in favor of the potential effectiveness of stimulating the Keap1/Nrf2/ARE system for the prevention and adjuvant therapy of neurodegenerative diseases.
In the last decades, transition elements doping of phyllosilicates greatly expanded the range of their applications including adsorption, catalysis, and composite materials manufacturing. The ...preparation of such materials and their subsequent operation often involves continuous thermal treatment. However, information on the thermal behavior of transition metal-doped phyllosilicates is still lacking. Here this gap was filled for the case of synthetic (CoxMg1-x)3Si2O5(OH)4 (x = 0.2, 0.4, 0.6, 0.8 and 1) phyllosilicate nanoscrolls treated in air, Ar and ArH2 gas flows in the 25–1000 °C range. Presence of Co2+, which could be both oxidized and reduced, initiated different phase changes depending on the atmosphere type. Two principal transitions occurred during heating in Ar flow. The first transition was related to the formation of sepiolite-like phase with partial amorphization (after 400 °C). The second transition was the crystallization process of orthosilicate (after 700 °C). These two main processes were accompanied by the appearance of Co3O4 when heated in air atmosphere (at about 300 °C) or the formation of Co0 nanoparticles when heated in ArH2 atmosphere (after 400 °C). The study revealed several morphological features during heat treatment in various gaseous media. First, Co0 nanoparticles oxidized and covered themselves with an oxide shell if they were not stabilized in the phyllosilicate matrix. Second, the metal tended to fill the nanoscrolls inner channel, forming extended nanorods. Finally, double-walled phyllosilicate nanotubes demonstrated exceptionally high thermal stability, conserving their morphology even up to 800 °C.
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•Thermal behavior of (Co,Mg)3Si2O5(OH)4 nanoscrolls was studied for the first time.•Phase transition to sepiolite-like phase followed by orthosilicate crystallization.•Thermally stable double-walled nanotubes retained their morphology up to 800 °C•Reduced metallic cobalt nanorods were located inside the nanoscroll channel.•Reduced metallic cobalt nanoparticles oxidized to Co@CoOy nanoparticles.
Surface templating of nano-multilayers is a promising step for the advanced industrial application of these nanomaterials. In the present work, the effect of focused ion beam modification of Ag/AlN ...nano-multilayer near-surface region on the Ag surface outflow is revealed. Surface patterning by ion beam irradiation leads to the formation of a higher amount of Ag crystals in relation to the intact surface region. Heat treatment initiates grooving of Ag grain boundaries, resulting in the formation of channels in the nano-multilayer volume. These channels act as pathways for mass transport of Ag to the film surface. Ion bombardment creates regions of high concentration of non-equilibrium defects, which locally increase the driving force for grooving and channeling, thereby promoting creation of more pathways for Ag surface migration. The obtained experimental results indicate that surface modification by focused ion beam can be used for production of nano-multilayers with designed templates of surface outflow.
•Ag crystals are formed on the nano-multilayer surface upon high-vacuum annealing.•The HeFIB surface modification results in a higher density of Ag crystals.•Annealing induces formation of channels in the nano-multilayer volume.
Purpose of research. Investigation of the relationship between the input and output characteristics of a fuzzy logic system based on the application of the area ratio method. The description of the ...specified method and the results obtained during modeling in a tabular processor is carried out using the means of illustrative presentation of information – visual programming. Methods. To study the area ratio method, we considered a fuzzy logic model containing two input variables with three triangular membership functions and one output variable with five triangular membership functions. A database of fuzzy rules has been formed. The degrees of activation of the output terms were determined using the minimax rule of output L. Zadeh. The defuzzification of the values was carried out using a model based on the area ratio method. Results. There are advantages of the area ratio method over traditional models, which consist in the ability to compensate for the main disadvantage - narrowing the defazzification interval. Using the proposed method, the possibility of using different numbers of variables on the input and output membership functions is studied. The results of experimental studies have shown that combining the parameters allows us to create a visual representation of the characteristics between the input and output variables. Conclusion. This article describes the area ratio method, which allows us to visualize the relationship between input and output variables. There are the main results of numerical modeling reflecting the specifics of the method. The study was conducted through visual programming, which provides a number of advantages, such as improving the quality of the software product, ensuring a clear structuring of the task and accessibility to human perception.
Alkylphosphinic acids, including long-chain ones, were synthesized in up to 76% yields from red phosphorus and
n
-AlkBr (Alk = C
4
–C
14
) under micellar catalysis conditions. The reaction proceeds ...efficiently and chemoselectively upon heating (85–90°C, 6 h) in a KOH/H
2
O/toluene/cetyltrimethylammonium bromide system.
Abstract
The article discusses a method for increasing the shelf life of meat pates by adding a natural antioxidant. Numerous studies show that the most popular and competitive food products are ...products that are convenient and easy to prepare in a short amount of time, easy to take with you as a snack, and products with a high-quality and safe composition that can be stored for a long time. The release of new pate products that do not require cold storage will significantly reduce production space, costs for the purchase and operation of equipment, and make such products universal for use in long-distance transport crossings and air travel.
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