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Negative electrodes for lithium-ion batteries prepared by electrochemical etching of single-crystalline silicon crystals demonstrate a high specific capacity per gram of the material and per unit of nominal anode area as well as a high stability during several hundreds and even thousands of cycles. However, industrial application of such structures is inexpedient in view of the high cost of the material and technology used. In this work we have investigated anodes based on disordered macropores in solar-grade n-Si obtained by photoanodization in a 4% HF solution in dimethyl formamide. The use of this organic electrolyte leads to the formation of layers with a porosity higher than in an aqueous electrolyte and ensures spontaneous separation of these layers from the substrate. The anodes have been prepared from macroporous membranes with a thickness of 48–86 μm and a porosity of 52–75%, and their electrochemical parameters have been studied. It is found that the geometrical parameters of the porous structure and experimental conditions determine the charge and discharge capacity and the cycle life of the anodes. In the regime of the charge capacity limited by 1000 mA h/g and charge/discharge rate C/5, the obtained anodes can stably operate during several hundreds of cycles, preserving a high (greater than 98%) Coulombic efficiency.

Inspiratory activity generated by superfusedin situ semi-isolated medullo-spinal preparations of newborn (one-day-old) and four- to five-day-old rats was recorded from then. phrenicus before and after transverse sectioning of the ventrolateral part of the medulla (VLPM) at different levels. Under similar experimental conditions, the frequency of inspiratory discharges (ID) and their integral intensity, reflecting the volume and temporal parameters of inspiration, are much lower in one-day-old rats, as compared with those in four- to five-day-old animals. Specific roles of different VLPM levels in respiration control in young rats are demonstrated. Transection of the VLPM below the most rostral VLPM portion, corresponding to theM chemosensitive zone, caused a significant increase in the ID frequency and a decrease in the ID integral intensity. Transection performed below the intermediate VLPM region, corresponding to theS chemosensitive zone, resulted in a significant decrease in both ID frequency and ID integral intensity, up to total ID blockade in 5 of 12 1-day-old preparations. This finding can be interpreted as an indication of morphofunctional immaturity of the respiratory network in the caudal VLPM regions in newborn animals. Comparative analysis of ID pattern showed that this activity in one-day-old rats is more or less gasping-like, while that in four- to five-day-old animals is eupnoe-like. The results allow us to conclude that the level of maturity of morphofunctional organization of medullary respiratory networks considerably differs in newborn and older animals. The mechanisms responsible for formation and control of respiratory activity in early postnatal period of rats are discussed.

The effects of blockers of opioid and serotonin receptors (naloxone and methisergide, respectively) on the respiratory activity recorded from then. phrenicus of semi-isolated medullo-spinal preparations (SIMSP) were studied in newborn (1-day-old) and 4- to 5-day-old rats. The preparations were superfusedin situ, and inspiratory discharges (ID) were recorded before and after transverse sections of the ventrolateral medullary regions (VLMR) at different levels. Naloxone evoked an increase in the ID frequency in then. phrenicus both at the initial configuration of preparations and after successive transections of the VLMR between theM andS chemosensitive zones and between theS andL zones. The relative intensity of this effect was significantly higher in newborn rats than in 4- to 5-day-old ones. In contrast, methisergide made the ID frequency lower at all configurations of the SIMSP, and this effect was more intensive in 4- to 5-day-old animals. In the course of progressive separations of more rostral VLMR zones, the effects of naloxone and methisergide applications on the ID frequency became weaker. This allows us to suppose that in newborn rats the rostral VLMR portions provide more intensive opioidergic inhibitory control influences on the activity of respiratory networks than those in 4- to 5-day-old animals. At the same time, tonic activating influences from serotonergic VLMR neurons on the mechanisms generating respiratory rhythm are more intensive in 4- to 5-day-old animals than those in newborn ones. Thus, it can be supposed that the levels of maturation of the opioid- and serotonergic neurotransmitter systems, which provide tonic control of respiratory activity generated in the VLMR, are different in newborn and 4- to 5-day-old animals. The problems of how the opioid- and serotonergic mechanisms controlling respiratory rhythm generation are formed in the course of early stages of ontogenetic development are discussed.

Electrophysiological properties of P neurons localized in the medullary dorsal respiratory cellular group and of vagal afferent fibers innervating these neurons were studied in acute experiments on nembutal-anesthetized cats with preserved spontaneous respiration. P neurons were shown to form a non-homogeneous cellular population. They generated phasic discharges during the whole inspiration period, but differed in their responses to lung inflation. These findings allowed us to classify P neurons as slowly adapting and rapidly adapting units, probably activated by slowly and rapidly adapting pulmonary receptors, respectively. Sensitivity of the slowly adapting P neurons to activation by the corresponding receptors and the mechanisms underlying the participation of the two types of P neurons in the reflex feedback between the respiratory center and lungs are discussed.

Anatomical and topographical organization of the structures of the caudal medullary region was studied in 3- and 21-day-old rats. A system of stereotaxic coordinates was proposed, and brain maps for the animals of these age groups were plotted. Topographic characteristics were given for the nuclei forming the medullary respiratory center: the lateral reticular nucleus,n. ambiguus, and the nuclei of the solitary tract, vagus and hypoglossal cranial nerves. These structures differ from each other in their cytoarchitectonics and in the changes in number during their neurons' postnatal development. The differences are suggested to result from the differences in morphological maturation of the neurons at early ontogenic stages.

The organization and role of a respiratory neuronal generator as a part of the medullary respiratory center, including the role of afferent systems in the mechanisms of initiation and regulation of the center cyclic activity, are considered. Intrinsic organization of the respiratory generator and specific features of its functioning are analyzed, and the two main hypotheses concerning the mechanisms of rhythmic respiratory activity generation are discussed.

Nonstationary heat exchange in a nontransparent plane-layered medium irradiated with a directional beam of pulsed radiation is investigated theoretically. The radiation is absorbed on the irradiated surface, which becomes a distributed source of heat. The propagation of the heat into the layers is described by the heat-conduction equation with nonlinear boundary conditions, which take into account convection and heat exchange with the radiation. Dimensionless parameters, on which the solution depends, are obtained, and their effect on the change of the surface temperatures of the layers with time for one- and two-layered media and also on the heat pulse transmitted through the medium is analyzed.

A comparative analysis was made of the distribution of vestibular efferent neurons projecting to the saccule and efferent cells sending out axons to the auditory nerve ("cochlear efferent neurons") in the guinea pig, using retrograde horseradish peroxidase axonal transport techniques. Saccular efferent neurons were discovered bilaterally in the subependymal granular layer at the base of the fourth cerebral ventricle and laterally to the facial nerve genu ispsilaterally in the parvocellular reticular nucleus, as well as nuclei of the superior olivary complex: the lateral olivary nucleus and lateral nucleus of the trapezoid body. Cochlear efferent neurons are located ipsilaterally in the pontine reticular caudal nucleus, in the anteroventral cochlear nucleus, and in the lateral and medial olivary nuclei. Neurons were found contralaterally in the medial nucleus of the trapezoid body. It thus emerged that location zones of vestibular saccular efferent neurons and those of cochlear efferent units partially overlapped. The possible involvement of saccular vestibular efferent neurons in the mechanisms of auditory perception is discussed.

The responses of 129 bulbospinal (BS) neurons were investigated an anesthetized cats during the expiration reflex evoked by mechanical stimulation of the vocal folds or electrostimulation of the superior laryngeal nerve. It was found that in addition to expiratory and inspiratory neurons, a large number of nonrespiratory BS cells localized bilaterially, primarily in the giant-cell tegmental fields, are activated. It is shown that expulsive expiration during this reflex is to a considerable extent provided by activation of non-respiratory BS neurons participating also in the transmission of descending influences from high-threshold afferents of other modalities.

A large number of complex experimental cases are considered which in recent years have been studied with the aid of the admittedly simplified apparatus of the Holstein theory. The fundamental Holstein equation is derived, starting with a system of coupled Boltzmann equations for the photons and the density of excited states. The derivation process provides opportunities for obtaining some intermediate kinetic equations with broader ranges of applicability than the Holstein equation. Some remarks are made concerning the combined transport in space of photons and excited atoms.

Neurons projecting to the ampullae of anterior, lateral, and posterior semicircular canals were identified in the guinea pig brainstem using horseradish peroxidase labeling techniques. Two groups of neurons forming bilateral connections were found, one located dorsally and the other ventrally to facial nerve trajectories. The dorsal group of vestibular efferent neurons projecting to all three canals was detected in the subependymal granular layer of the floor of the 4th ventricle lateral to the facial nerve genu and in the abducent nerve nucleus. Efferent neurons belonging to the ventral group were unevenly distributed through different areas of the parvocellularis nucleus and the rostral portion of the pontine caudal reticular nucleus. The morphological characteristics and distribution pattern of these cells are taken as confirmation of their heterogeneity of neuronal and functional organization in the vestibular efferent system of semicircular canal ampullae.

The emission of radiation from a plasma volume upsets the Boltzmann equilibrium. A number of authors have proposed criteria for approximate testing of the existence of local thermodynamic equilibrium on the basis of collision and radiation processes. However, those criteria give excessive values, because they do not take into account radiation resorption, which can “moderate” the test conditions. The present article is concerned with the influence of radiation resorption on the criterion of the existence of local thermodynamic equilibrium in a low-temperature plasma. The domain of existence of local thermodynamic equilibrium (in the sense of Saha-Boltzmann equilibrium) is calculated for electric arcs.

The motion of a charged particle in a rotating, uniform magnetic field is investigated. Expressions are obtained for the domains of steady-state motion and for the particle trajectories. The investigation includes a treatment of conditions specifying the particle localization within the bounded space domain.

Gear's predictor-corrector multistep method is applied to a rigid system of nonlinear ordinary differential equations, describing vibrational kinetic processes in molecular (diatomic) gas. The applicability of Naidis's formulas, for the linear problem is studied. The evolution of the starting Boltzmann distribution to the quasiequilibrium Trinor distribution is studied. The vibrational relaxation curves are calculated taking into account VV and VT processes and the possibilities of a more complicated starting physical model are examined.

Neurons with projections into the vestibular receptor apparatus (efferent vestibular neurons) were identified in different medullary regions by retrograde labeling with horseradish peroxidase and transport-specific fluorochromes in the guinea pig. Two groups of efferent vestibular neurons could be distinguished, located dorsally and ventrally to the facial nerve fiber pathway. The dorsal group of efferent vestbular neurons consisted of small cells located close to the genu and the root of the facial nerve and the subependymal granular layer of the 4th ventricle floor. The ventral group was primarily composed of medium-sized cells, usually with only slight tracer accumulation; these were scattered over an extensive area of the lateral tegmental field within nucleus reticularis lateralis parvocellularis. The question of whether the test cells belong to the system of true vestibular efferents and satellite cells is discussed in the light of findings on cell location, morphology, and pattern of tracer accumulation.

Intrabulbar connections of respiratory nuclei and the medullary reticular formation and also descending pathways from these structures in the spinal cord were studied by the retrograde horseradish peroxidase axonal transport method in cats. Neurons of the nucleus ambiguus and nucleus retroambigualis (ventral respiratory group) and of the ventrolateral part of the nucleus of the tractus solitarius (dorsal respiratory group) were shown to form direct two-way connections with each other and with the medial region of the medulla. Neurons of the pneumotaxic center send uncrossed axons to the nucleus ambiguus and to the medial medullary reticular formation. Neurons of the contralateral homonymous nucleus and neurons of the nucleus of the tractus solitarius are sources of projections of the locus coeruleus. A well developed system of direct connections was found between neurons of respiratory nuclei of the two halves of the brain. The possible role of these nuclear formations in genesis of the respiratory rhythm and regulation of the respiratory and other motor functions of the reticular formation is discussed.

A spectral method for determination of local temperatures in an emitting volume is discussed. The problem of reconstruction of emissivity in the case of a medium of arbitrary configuration is solved by regularization.

Electrophysiological characteristics of superior laryngeal nerve fibers and reflex responses in respiratory motor nerves and the recurrent nerve were investigated in acute experiments on cats under superficial pentobarbital anesthesia. Analysis of the compound action potential in the superior laryngeal nerve revealed three distinct groups of afferent fibers subserving different functions: group Aβ, responsible for proprioceptive mechanisms of coordination of activity of the laryngeal muscles; group Aγ(β3), responsible for feedback mechanisms between the receptor apparatus of the mucous membrane and muscles of the larynx and bulbar respiratory neurons, and group Aδ, responsible for the development of protective respiratory reflexes.

Some formulations of the problem of reconstructing the potential of the two-body interaction from the temperature dependence of the second virial coefficient are considered. For three-parameter potential models (Morse and Kihara) the formalism of the Fisher matrix is used to calculate the coefficients of the amplification of the errors in the determination of each of the parameters. For the general case of the nonparametric approach a scheme of formal linearization of the problem is given and conditions for unique solution of it found. The example of the reconstruction of the potential of Maxwellian molecules is given. Some new possibilities are noted for the unique reconstruction on the basis of the temperature dependences of the transport coefficients.

The influence of the efferent vestibular system on vestibulo-spinal activity was investigated during experiments on guinea pigs decerebrated and following cerebellar extirpation at precollincular level. Efferent vestibular neurons forming compact groups ventromedially to the vestibular nuclei were excited by means of electrical stimulation. Electromyographic activity in the triceps brachii extensor muscles of the right and left forelimbs was adopted as a test reaction (crossed extensor reflex and locomotor activity produced by stimulating the mesencephalic locomotor region). Adequate stimulation of the vestibular apparatus was accomplished by static tilting and cyclic shifting of the animal around its longitudinal axis at angles of ±20°. The efferent vestibular system was found to exert a bilateral inhibitory action on vestibulo-spinal activity. Vestibular efferent stimulation produced a reduction in the intensity of vestibulo-fugal influences: it does not change the dynamics of vestibulo-spinal reflex effects, however. Mechanisms of vestibular efferent action on vestibular control of spinal motor activity are discussed.

The firing activity pattern of 50 slow-adapting pulmonary receptors (SAPR) was investigated in anesthetized cats under conditions of normal respiration and quasi-static and dynamic lung inflation. A non-linear relationship was found between change in activity rate and lung capacity during inspiration in 74% of SAPR; the rate rose in proportion to an increase in lung volume in a further 16%, and changes in the rate during the respiratory cycle followed a different “atypical” pattern in the remaining 10%. A non-linear relationship persisted between rate and volume during quasi-static inflation of the lungs in40% of the SAPR investigated (linear in 50% of cases). During dynamic inflation, “nonlinear” and “linear” SAPR numbered 70% and 20% respectively. Summated flow of impulses from all SAPR investigated stood in a non-linear relationship to lung volume during normal breathing. Reasons for the different relationships between the activity rate of individual SAPR and lung volume during normal pulmonary ventilation and during inflation of the lungs are discussed together with possible synaptic connections between pulmonary afferents and bulbar respiratory neurons.

The role of diffusion of the components of the gas mixture is the generation mechanism of a waveguide CO2 laser is analyzed. A method is proposed for reducing the multicomponent problem of linear diffusion with dissipation to a one-component problem. The superposition of relaxation modes for a cylindrical waveguide is considered. The diffusion contribution to the loss of electromagnetic energy is estimated for the case of the field hybrid mode EH11 of a dielectric waveguide. The rapid increase in the loss for a SiO2 waveguide tube and the observation of the filtration properties of the laser in conditions when the diffusion is taken into account are noted.

Functional characteristics of single reticulo-spinal fibers of the ventral funiculi were studied at the level of the 10th thoracic segment of the spinal cord in anesthetized (with chloralose and pentobarbital) and decerebrate cats after removal of the cerebellum. The reticulospinal tract of the ventral funiculus consists of a broad spectrum of rhythmically active and "silent" fibers, divided into three groups: fibers with a high (65–110 m/sec), medium (45–60 m/sec), and low (20–40 m/sec) conduction velocity. Spontaneous rhythmic activity is more characteristic of the fibers of the last two groups. The quantitative ratio between rhythmically active and silent fibers was about twice as high in the decerebrate as in the anesthetized animals. Depending on the character of distribution of interspike intervals the spontaneous activity of the reticulo-spinal fibers of the animals of both groups could be classified in three types: I) with a uniform distribution of interval; II) with a tendency toward grouping of spikes into volleys; III) with marked grouping of the intervals. Fibers with low and medium conduction velocities more often had spontaneous activity of types I and II, while fibers with a high conduction velocity more often had activity of types II and III. The possible functional significance of the reticulo-spinal fibers of the ventral funiculi with different conduction velocities and types of spontaneous activity is discussed.

The article presents a stable algorithm of solving an integral equation of the first kind taking into account the a priori information on the sought solution.

Synaptic processes in various functional groups of thoracic motoneurons (segments T9–T11) were investigated in anesthetized (chloralose and Nembutal), decerebrate, and spinal cats. Visceral stimulation in animals with an intact CNS during artificial respiration evokes the development of primary (latent period under 12 msec) and secondary (latent period over 30 msec) PSPs in the motoneurons. The primary PSPs consist of early and principal components. The early component is due to excitation of group Aβ2 and Aγ visceral afferents, the principal PSP to excitation of the Aγδ group. The principal component in motoneurons of the internal and external intercostal muscles and abdominal muscles is excitatory, while in motoneurons innervating the spinal muscles it is excitatory—inhibitory or inhibitory. The secondary PSPs as a rule are excitatory and are due to activation of fibers of the Aγδ group. During natural respiration the primary PSPs of motoneurons of the intercostal muscles and abdominal muscles are predominantly inhibitory. In spinal animals no secondary responses are present and the primary becomes entirely excitatory regardless of the functional class of the motoneurons. The mechanisms of reciprocal activation of thoracic motoneurons by visceral impulses in animals during artificial and natural respiration are discussed.

Synaptic processes in various functional groups of thoracic motoneurons (Th9-Th11) evoked by stimulation of segmental nerves were investigated in anesthetized and decerebrate cats. No reciprocal relations were found between these groups of motoneurons. Only excitatory mono- and polysynaptic responses were recorded in the motoneurons of the principal intercostal nerve following stimulation of the homonymous nerve. Activation of the afferents of the external intercostal muscle and dorsal branches does not cause noticeable synaptic processes in these motoneurons; much more rarely it is accompanied by the development of low-amplitude polysynaptic EPSP's. In motoneurons of the dorsal branches, stimulation of homonymous nerves leads to the appearance of simple, short-latent EPSP's. Late responses of the IPSP or EPSP - IPSP type with a predominance of the inhibitory component were observed in most motoneurons of this type following activation of the afferent fibers of the principal intercostal nerve. In other motoneurons of the dorsal muscles, stimulation of the main intercostal nerve (and nerve of the external intercostal muscle) did not evoke apparent synpatic processes. EPSP's (mono- and polysynaptic) appeared in the motoneurons of the external intercostal muscle following stimulation of the homonymous and main intercostal nerves. Activation of the afferents of the dorsal branches was ineffective. The character of the synaptic responses of the respiratory motoneurons to segmental afferent stimulation, investigated under conditions of spontaneous respiration, was different. The characteristics of synaptic activation of thoracic motoneurons by segmental afferents under conditions of hyperventilation apnea and during spontaneous breathing of the animals are discussed.

The following are considered: the principles involved in selecting a system of trial functions for the variational method of solving the Holstein problem; a method for determining the eigenfunctions for the cylindrical problem; the Voigt distribution of intensity along the profile of a nonreabsorbed line; and a method for finding eigenvalues for a layer of moderate optical thickness.

Responses of lumbar interneurons located in the most lateral regions of Rexed's laminae IV–VII to stimulation of the medial longitudinal bundle and gigantocellular reticular nucleus of medullary pyramids, red nucleus, and peripheral nerves were investigated in cats anesthetized with pentobarbital. Stimulation of the reticulospinal fibers evoked monosynaptic excitation of many interneurons specialized for transmitting activity of the lateral descending systems, but not of peripheral afferents. Convergence of excitatory influences of all three descending systems (cortico-, rubro-, and reticulospinal) was observed on some cells of this group. In addition, monosynaptic "reticular" E PSPs appeared in interneurons transmitting activity of group Ia muscle fibers and in some interneurons of the flexor reflex afferent system. Stimulation of reticulospinal fibers evoked IPSPs in some neurons of this last group. Neurons not exposed to reticulofugal influences (both specialized neurons and interneurons of segmental reflex arcs) were located chiefly in the dorsal zones of the region studied. Recordings were also obtained from single fibers of the lateral reticulospinal tracts (conduction velocity from 26 to 81 m/sec).

The emitting layer formed by laser heating is highly inhomogeneous and of high optical density, so the concentration of an element is deduced from the spectral separation of the self reversal maxima, A theoretical study is presented for this separation as a function of the optical thickness of the layer for various excitation conditions.

The IR spectra of 18 substituted pyrroles and 6 substituted dipyrrylmethanes are investigated. It is shown that the position of the valence vibrations frequency of the free NH group, νfree NH depends on the number of substituents in the ring. The frequency is influenced by the electronegativity of a substituent, the effect of an α- being much more marked than that of a β-substituent. The stability of the hydrogen bond increases with increase in substituent electronegativity. When two electronegative substituents occupy the α and β positions, they have a mutually weakening effect. The νC=O (acetyl) absorption bands in pyrrolecontaining compounds are situated 40–60 cm−1 lower than in aromatic ketones and greatly depend on the position and nature of the substituent in the pyrrole ring.

We studied synaptic processes in motoneurons of thoracic segments (TIX-TXI) evoked by stimulation of the medial area of the giant-cell reticular nucleus in decerebrated cats. Monosynaptic EPSP were recorded in the majority of investigated motoneurons upon activation of the most rapidly conducting reticulospinal fibers. In some cells, such monosynaptic EPSP were accompanied by late EPSP or IPSP. Amplitude of monosynaptic EPSP attained 5 mV, but this value usually was insufficient for development of an action potential. Upon summation of single monosynaptic EPSP, the membrane potential reached the critical level and an action potential arose in the motoneuron. The efficiency of summary processes evoked by stimulation of the reticular formation exceeded the intensity of synaptic processes that arise in thoracic motoneurons on stimulating the nucleus of Deiters. Functional characteristics of reticular and vestibular monosynaptic EPSP are discussed in the work.

The system of linear equations of multicomponent convective diffusion is reduced consistently with allowance for the features of the relevant laser devices. A criterion for the realization of a purely diffusion regime is established. A method of diagonalization of the diffusion coefficient matrix is given; it reduces the multicomponent problem to a series of one-component problems. The superposition of relaxation modes is discussed. A diffusion type hydrofluoric laser illustrates the influence of angular asymmetry of the particles on the output power of the radiation.

The dimethyl ether of racemic lyenzinine is synthesized by sucessive building-up of tetrahydroisoquinoline bases. The utility of this method for preparing hydroxy compounds is demonstrated. The benzyl analog of the diacetate of bisdehydroisolyenzinine is synthesized.

Synaptic processes of 119 thoracic spinal interneurons (T10–11) were investigated in anesthetized cats in response to stimulation of the medial and central zones of the gigantocellular nucleus in the medulla and the ventral columns of the spinal cord. Fast (90–130 m/sec) reticulospinal fibers running in the ventral column were found to produce monosynaptic or disynaptic excitation of interneurons of Rexed's layers VII–VIII, which are connected monosynaptically with group I muscle afferents, and interneurons excited both by group I muscle afferents and low-threshold cutaneous afferents. In most neurons of layer IV, connected monosynaptically with low-threshold cutaneous afferents, and in neurons of layers VII–VIII excited by afferents of the flexor reflex no marked postsynaptic processes were observed during stimulation of the reticular formation. Excitatory, inhibitory, and mixed PS Ps during activation of reticulospinal fibers were found in 14 neurons, high-threshold afferents in which evoked predominantly polysynaptic IPSPs. Seventeen neurons activated monosynaptically by reticulospinal fibers and not responding to stimulation of segmental afferents were found in the medial part of the ventral horn (layers VII–VIII).