The problem of generation multiple uncorrected turbulent flow states subject to low computational costs is among the key questions affecting the overall performance of algorithms for modeling ...incompressible turbulent flows. The current paper proposes the computational procedure that can be used to generate multiple initial turbulent flow fields. This procedure is based on the fact of exponential divergence of the phase trajectories for turbulent flows and allows to perform the corresponding simulations without priori information about the characteristic decorrelation time scale. The preliminary validation results of the proposed procedure demonstrate a possibility of additional 10% speedup when modeling turbulent flows by using proposed in this paper numerical algorithm with the algorithms combining averaging in time with ensemble averaging.
Spherical particles (SPs) generated by thermally denatured tobacco mosaic virus (TMV) coat protein can act as an adjuvant, as they are able to enhance the magnitude and longevity of immune responses ...to different antigens.
Here, the toxicity of TMV SPs was assessed prior to it being offered as a universal safe adjuvant for the development of vaccine candidates. The evaluation included nonclinical studies of a local tolerance following the single administration of TMV SPs, and of the local and systemic effects following repeated administrations of TMV SPs. These were conducted in mice, rats and rabbits. General health status, haematology and blood chemistry parameters were monitored on a regular basis. Also, reproductive and development toxicity were studied. No significant signs of toxicity were detected following single or repeated administrations of the adjuvant (TMV SPs).
The absence of toxicological effects following the injection of TMV SPs is promising for the further development of recombinant vaccine candidates with TMV SPs as an adjuvant.
•The toxic effects of TMV SPs (structurally modified helical plant virus) were studied.•Minor reversible deviations in histology and blood tests are observed at high doses of TMV SPs.•Immunotoxicity, reproductive and developmental toxicity of TMV SPs are not detected.•TMV SPs are the promising and safe adjuvant for new vaccine candidates development.
Disturbance evolution in developed turbulent flows in a plane channel is numerically investigated at the Reynolds numbers up to Re
τ
= 586. Steady turbulent flows calculated on the basis of the ...solution of the incompressible Navier—Stokes equations are then used as the baseline flows in studying the disturbance development process. The values of the highest Lyapunov exponent (HLE) λ
1
are found and the instantaneous and statistical properties of the corresponding leading Lyapunov vector (LLV) are determined. Under arbitrary initial conditions the regime of the exponential disturbance growth ~ exp(λ
1
t
) is reached for a time Δ
t
+
< 50. It is found that the HLE value increases with the Reynolds number from λ
1
+
≈ 0.021 at Re
τ
= 180 to λ
1
+
≈ 0.026 at Re
τ
= 586. The LLV exhibits itself in the form of time- and space-localized spots of highly intense pulsations, concentrated in the buffer layer region. The distributions of the r.m.s. intensities of the velocity and vorticity pulsations in the LLV are qualitatively similar with the corresponding distributions in the main flow with near-wall streaks artificially extracted from it. The difference is a large disturbance concentration in the vicinity of the buffer layer,
y
+
= 10–30, and a relatively high (about 80% higher) vorticity pulsations amplitude. Basing upon the energy spectra of the velocity and vorticity pulsations we determined the integral spatial scales of the structures in the LLV field. It is found that the LLV structures are on average half as wide and long as the corresponding structures in the main flow. The contributions of all the terms included in the expression for the production of the kinetic energy of disturbances are determined. It is shown that the process of disturbance development is essentially controlled by the main flow inhomogeneity and the occurrence of transverse motion in it. Neglecting these factors leads to a considerable underestimation of the disturbance growth rate. Contrariwise, the presence of near-wall streaks in the main flow does not play a considerable role in the LLV disturbance development. The artificial extraction of the streaks from the main flow field does not change the nature of disturbance growth.
The solution of the Navier–Stokes equations which reproduces some qualitative features of localized turbulent structures developed in circular pipes at transitional Reynolds numbers is numerically ...investigated. In the phase space this solution corresponds to the limiting state of the solution which evolves along the separatrix dividing the regions of attraction of the solutions corresponding to the laminar and turbulent flow regimes. Relative simplicity of the spatial and temporal behavior of the limiting solution on the separatrix makes it possible to investigate it in detail. In particular, the nonlinear mechanism of the onset of streamwise vortices responsible for sustainment of near-wall streaks whose instability ensures the presence of fluctuations is revealed.
The current MMN study investigates whether brain lateralization during automatic discrimination of sound stimuli moving at different velocities is consistent with one of the three models of ...asymmetry: the right-hemispheric dominance model, the contralateral dominance model, or the neglect model. Auditory event-related potentials (ERPs) were recorded for three patterns of sound motion produced by linear or abrupt changes of interaural time differences. The slow motion (450deg/s) was used as standard, and the fast motion (620deg/s) and the abrupt sound shift served as deviants in the oddball blocks. All stimuli had the same onset/offset spatial positions. We compared the effects of the recording side (left, right) and of the direction of sound displacement (ipsi- or contralateral with reference to the side of recording) on the ERPs and mismatch negativity (MMN). Our results indicated different patterns of asymmetry for the ERPs and MMN responses. The ERPs showed a velocity-independent right-hemispheric dominance that emerged at the descending limb of N1 wave (at around 120–160ms) and could be related to overall context of the preattentive spatial perception. The MMNs elicited in the left hemisphere (at around 230–270ms) exhibited a contralateral dominance, whereas the right-hemispheric MMNs were insensitive to the direction of sound displacement. These differences in contralaterality between MMN responses produced by the left and the right hemisphere favour the neglect model of the preattentive motion processing indexed by MMN.
•We studied the lateralization of ERPs and MMNs to smooth and abrupt auditory motion.•The N1 and P2 responses were stronger in the right hemisphere.•The MMN responses showed no right-hemispheric dominance.•Direction of motion affected only the left-hemispheric ERPs and MMNs.•Sound velocity had no consistent effect on the lateralization of ERPs and MMNs.
Using quantum entanglement we propose a new algorithm for a hypothetical superluminal connection between two macroscopic observers. It is shown that this algorithm is unworkable due to the property ...of entanglement monogamy. It is a new look at the role of the monogamy of entanglement in quantum mechanics. The ansible is a hypothetical device for superluminal connection from science fiction novels by Ursula Kroeber Le Guin.
Abstract
The work is dedicated to the research and development of methods and algorithms that automate and support the process of technical creativity, from the point of automated creation of musical ...compositions with different genres. The method is based on the use of neural networks to predict composition, and also suggests using various models that have been trained by songs in certain genres to improve the quality of the resulting musical composition. This work describes the algorithm itself, the process of collecting and classifying data for training, the process of training a neural network. In addition, it describes the process of choosing a neural network architecture. Also, the work proposes a system architecture for the automated generation of compositions using the proposed algorithm.
Elastic anisotropy is an important property of crustal and mantle rocks. This study investigates the contribution of oriented microcracks and crystallographic (LPO) and shape preferred orientation ...(SPO) to the bulk elastic anisotropy of a strongly foliated biotite gneiss, using different methodologies. The rock is felsic in composition (about 70 vol.% SiO
2) and made up by about 40 vol.% quartz, 37 vol.% plagioclase and 23 vol.% biotite. Measurements of compressional (Vp) and shear wave (Vs) velocities on a sample cube in the three foliation-related structural directions (up to 600 MPa) and of the 3D P-wave velocity distribution on a sample sphere (up to 200 MPa) revealed a strong pressure sensitivity of Vp, Vs and P-wave anisotropy in the low pressure range. A major contribution to bulk anisotropy is from biotite. Importantly, intercrystalline and intracrystalline cracks are closely linked to the morphologic sheet plane (001) of the biotite minerals, leading to very high anisotropy at low pressure. Above about 150 MPa the effect of cracks is almost eliminated, due to progressive closure of microcracks. The residual (pressure-independent) part of velocity anisotropy is mainly caused by the strong alignment of the platy biotite minerals, displaying a strong SPO and LPO. Calculation of the 3D velocity distribution based on neutron diffraction texture measurements of biotite, quartz, and plagioclase and their single-crystal properties give evidence for an important contribution of the biotite LPO to the intrinsic velocity anisotropy, confirming the experimental findings that maximum and minimum velocities and shear wave splitting are closely related to foliation. Comparison of the LPO-based calculated anisotropy (about 8%) with measured intrinsic anisotropy (about 15% at 600 MPa) give hints for a major contribution of SPO to the bulk anisotropy of the rock.
The evolution of small perturbations in turbulent Couette flow is investigated numerically at the Reynolds numbers Re
τ
from 35 to 125. Steady-state turbulent flows calculated on the basis of solving ...the Navier-Stokes equations are used as the basic flow to study the process of development of the perturbations against their background. The values of the senior Lyapunov exponent λ
1
which characterizes the maximum growth rate of small perturbations in the stochastic systems are determined. It is found that the exponent, being normalized by the near-wall scales, is equal to λ
1
~ 0.02. This is in agreement with the results of the previous investigations of turbulent flows in the circular pipe and plane channel. It is shown that the λ
1
, whose value is smaller by three times and which was obtained earlier in calculating the Lyapunov spectrum in Couette flow at Reτ = 35 in the so-called “minimum channel”, can be explained by insufficient dimension of the computational domain but not by smallness of the Reynolds number.
The relevance of the work. Today it is considered that metabasite rock associations widespread in the Trans-Angara part of the Yenisei Ridge are products of rifting processes caused by activity of ...plume and breakdown of the Rodinia supercontinent during ~1100–700 Ma. In this case, data on their absolute age are the subject of discussion. The paper considers the Neoproterozoic metamorphic events using thermodynamic features of formation of the studied amphibolite manifestations as an example and their place in geodynamic model of formation of the Yenisei Ridge, as well as the role of syn/postcollisional granitoid magmatism in age rejuvenation of Transangar amphibolites. The aim of the research is to establish the main mineral paragenesis of amphibolites and their secondary mineralization; determine the thermodynamic conditions of metamorphism and its main stages; correlate the nature of metamorphism with the metamorphic events of the region and determine its role in the formation of the modern appearance of the Yenisei Ridge; identify the reasons responsible for the mismatch between the age of the studied amphibolites according to the Ar-Ar isotopy and the accepted dating the Zaangarya metabasalts. Objects: amphibolites of the Shumikhinsky metapicritic-basalt complex, which is a part of the malogarevskaya metamorfic series of the Late Archean age (?) occurring among carbonate rocks and crystalline schists in the valleys of the Tyrad and Malaya Kadra river basins and the Tei and Panimba tributaries respectively. Methods. Chemical composition of the mineral phases was obtained using an analytical complex for scanning electron microscopy and microanalysis based on a TESCAN VEGA II LMU scanning electron microscope, combined with an Oxford INCA Energy 350 in the Center for Collective Use «Analytical Center of the Geochemistry of Natural Systems» of the National Research Tomsk State University. Based on the data the crystal chemical formulas of minerals were calculated, classification and geothermobarometric diagrams were constructed. Results. The authors established general paragenesis of amphibolites of the studied manifestations: Hbl+Pl (XAn=0,28–0,38)+Qz+Ilm (Sph)+Fsp with secondary local development of Act, Zo, Bt, Ms and Chl. Thermodynamic parameters of metamorphism of metabasites correspond to the conditions of low-temperature zones of the amphibolite facies (555–475 °С, 5–7,5 kbar) with the dynamics of pressure increase against the general background of gradual cooling. Amphibolites are derivatives of collision metamorphism (~880–800 Ma), which appeared in the accretionary conditions of previously split tectonic blocks of the Siberian craton. The local development of potassium feldspar, actinolitization, and chloritization (344–199 °С) refers to superimposed processes under reheating conditions and may be associated with the final stage of the Grenville tectonic events accompanied by syn/postcollisional granitoid magmatism (γR3ta, 760–630 Ma). It could become a cause of age rejuvenation of the studied metabasites (707–675 Ma).
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