Studies have shown that in recurrent neural networks, a conditioned signal (CS) from “direction cells” acquires the ability to activate the sequence of neurons (“place cells”) with which it was ...associated in past experience (“replay”). The neurons in this model are connected by glutamatergic synapses with high concentrations and proportions of NMDA receptors; the CS operates only via synapses with AMPA receptors. The matrix of connections of the CS is structurally identical to the matrix of recurrent connections. Training potentiates directional connections in association with the nearest collaterals, when the trailing front of synaptic arousal from the preceding neurons in the activation sequence coincides with the leading front of depolarization of the next. At each stage, changes in the matrix of CS connections are functionally equivalent to changes in the matrix of recurrent connections. As a result, the CS acquires the ability to potentiate the conductivity of NMDA channels (to generate an NMDA spike) in recurrent connections in the associated sequence. Different CS become pointers to different sequences.
Mechanisms of plasmon and polariton attenuation of solar radiation are successively activated in crystal nanoparticles of reduced (doped with oxygen vacancies) tungsten trioxide and titanium dioxide ...doped with metals with a valence of 5 or 6 upon electrochemical injection of electrons followed by injection of positively charged ions. Application of mesoporous electrodes fabricated from such nanoparticles in electrochromic glass makes possible separate dynamic regulation of transmission of visible light and near-infrared radiation, which enables gradual change of the glass state from light warm to light cold and further to dark cold. Results of studies of electrochromic glasses with separate regulation of transmission of visible light and near-infrared radiation are analyzed. Information on the influence of structural characteristics of the mesoporous electrode and the type of the electrolyte on optical spectral properties, duration of transient processes, and cyclic stability of the device are summarized. It is established that electrochromic glasses with nanostructured one-component electrodes fabricated from reduced tungsten trioxide and doped titanium dioxide exhibit optimal optical, exploitation, and technological properties.
A model of the neural mechanism of instrumentalization (spontaneous reproduction) of movements induced by reinforcing stimulation of the motor cortex is presented. Instrumentalization is based on ...strengthening of the excitatory connections of cortical pyramidal neurons: 1) with dopamine neurons and 2) with each other in conditions of “dopamine modulation.” Correct changes to connections between pyramidal neurons are critically dependent on weakening of modulation immediately after neuron activity reaches the target state.
Structural and energy characteristics of the nanomoieties of the (C
2
H
5
)
3
N–CH
3
SO
3
H system are determined by IR spectroscopy and quantum chemistry methods in the range from 100% ...methanesulfonic acid to the 2.2:1 ratio, after which the solution solidifies. The established equilibrium composition of the system indicates the presence of six concentration-structural zones. The first one (100% CH
3
SO
3
H) contains 3CH
3
SO
3
H trimers and small amounts of 2CH
3
SO
3
H dimers and 4CH
3
SO
3
H tetramers. The second zone (0:1-1:3), in addition to the above self-associates, contains (C
2
H
5
)
3
N·3CH
3
SO
3
H complexes. Other zones simultaneously contain two types of structural elements: (C
2
H
5
)
3
N·3CH
3
SO
3
H and (C
2
H
5
)
3
N·2CH
3
SO
3
H in the third zone (1:3-1:2); (C
2
H
5
)
3
N·2CH
3
SO
3
H and 2(C
2
H
5
)
3
N·2CH
3
SO
3
H in the fourth zone (1:2-1:1); 2(C
2
H
5
)
3
N·2CH
3
SO
3
H complexes and moieties of polymer chains with the 2:1 composition in the fifth zone (1:1-2:1). The sixth zone (from 2:1 to the solidification ratio) contains chain moieties with the 2:1 composition and voluminous nanomoieties consisting of several chain moieties interconnected by (C
2
H
5
)
3
N molecules. At the molecular level, the mechanism responsible for the transition of the (C
2
H
5
)
3
N–CH
3
SO
3
H solution into the solid phase is elucidated. It is shown that
ion pairs are structure-forming and stabilizing elements of the (C
2
H
5
)
3
N–CH
3
SO
3
H system. The most energy favorable complex 2(C
2
H
5
)
3
N·2CH
3
SO
3
H consists of two ion pairs.
Dense microparticles form in thermotropic hydrogels upon temperature increase above the temperature of a volume phase transition, which causes a hydrogel transition from a transparent state to a ...milky-white light scattering state. Experimental and analytical data related to light scattering properties of thermotropic hydrogels are analyzed. The size of dense hydrogel particles plays a crucial role in determining the character of transmission and scattering of solar radiation. A considerable part of solar radiation experiences backscattering when the size of the microparticles exceeds 200 nm, which enables using such hydrogels for controlling the amount of transmitted solar radiation. Addition of dispersed plasmon nanoparticles into a hydrogel allows tuning its transition from transparent to light-scattering state so that it takes place at fixed intensity of solar radiation.
The results of research on the development and application of optical elements placed in the upper part of the window in order to redirect sunlight to the ceiling and into the interior of the room ...have been summarized and analyzed. There has been a steady trend of transferring such devices to the micro level. The article has described the structures and optical characteristics of three types of the optical microstructures embedded in double-glazed windows: microprismatic films, panels with prismatic microstructures on two sides, and films with embedded micro-mirrors. It has been noted that the use of curved surfaces instead of flat ones in microstructures improves the optical properties and increases the uniformity of the redirected sunlight flux. The designs and properties of optical microelectromechanical systems: switchable micro-mirrors and micro-blinds that were manufactured using microelectronics technology, have been generalized.
At the end of the 20th century, the phenomenon of optical properties changing from mirror metal to transparent upon hydrogenation of thin films of some chromogenic materials was discovered. Such ...devices were called “switchable mirror.” The amazing properties of the new materials and the possibility of creating smart windows on their basis have caused an explosive growth in the number of their studies. However, insufficient light transmission in the transparent state and accelerated degradation of mirrors during cyclic switching quickly extinguished interest in them and sharply reduced the intensity of their development. Persistent 20-year research in improving the optical properties and durability of gas- and electrochromic switchable mirrors has allowed bringing these devices to a level close to practical application. An analysis and generalization of the results of the development of gas- and electrochromic switchable mirrors and an assessment of the prospects of commercial implementation of smart windows based on them have been presented.
Analysis and generalization of the results of investigations devoted to the improvement of optical properties have been carried out, and descriptions of a structure and a reaction mechanism of ...available and promising window glasses with solar radiation are presented. All devices are divided into groups with static constant and dynamic regulated spectral characteristics. The group of static glasses includes heat-protective and spectrally selective glasses with low-emissivity coatings and infrared filters with dispersed plasmonic nanoparticles. Electrochromic glasses, nanostructured dynamic infrared filters, and glasses with separated regulation of the transmission of visible-light and near-infrared radiation are dynamic devices. It is noted that the use of mesoporous films made of plasmonic nanoparticles open up especially wide possibilities. Their application allows one to realize a dynamic separated regulation of the transmission of visible light and nearinfrared radiation in which, under the gradual increase in the electric potential on the glass, mechanisms of plasmon and polaron reduction of solar radiation gradually change the glass’ condition from light warm to light cold and then to dark cold consecutively.
In an electrochemical cell with electrolyte containing silver or copper salts, the metal deposition takes place on the surface of a transparent electrically conducting coating. Under certain ...conditions, the metal film becomes specular and the electrochemical cell periodically switches from transparent to mirror state in response to changes in the voltage. The data obtained on electrochemical cells switchable between transparent to mirror states are analyzed. It is noted that the electrolyte properties play the decisive role in characteristics of such devices. Their prototypes with three optical states: transparent‑transient semitransparent‑mirror are realized recently. The modes are achieved in which the mirror state is preserved for a long period (over 2 h) at switched-off voltage (deenergized state). These results allow us to expect that the development of electrochemically switchable glasses-mirrors for windows will soon reach its commercial stage.
A method of separately combined analysis of the process of radiant-convective heat transfer through the central part of the double-glazed windows is developed. The problem of heat transfer by ...radiation through a double-glazed window is formulated and a solution is obtained in an analytical form. The solution is applicable for all types of double-glazed windows with a given number, characteristics and location of low-emission coatings. The possibilities of reducing radiant heat losses through double-glazed windows due to an increase in the number of glasses and the use of glasses with low-emission heat-protective coatings are analyzed in detail.
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