Frequency-domain analysis for pulsating combustion of gaseous fuel

Pulsating combustion is among combustion control methods used to suppress formation of NOx. Past experiments showed that the dependency of NOx content from pulsation rate has a minimum. A measuring unit was set up to study torch behavior in infrared band. To study pulsating combustion of gaseous fuel a thermographic camera was used. Thermographic sequences were recorded using the instrument FLIR 7700M with the resolution of 320×240 pixels at the frame rate of 412 Hz. The experiments resulted in obtaining thermographic sequences radiation intensity fields in the longitudinal section of the torch at different pulsation rates. The obtained raw data was preprocessed to obtain distributions of quantities of pixels corresponding to temperatures in each frame, as well as time-domain series for changes of the torch core longitudinal section area. Frequency-domain analysis was run for each time-domain series using Fast Fourier transform (FFT). The results demonstrate that the first maximum of spectral density coincides with the control action rate. The spectrum also contains pronounced second and third harmonics. For each spectrum of the time-domain series signal-to-noise ratio (SNR) was calculated. Comparison of different SNR shows that maximum impact of pulsation control on torch radiation intensity takes place at the on/off valve opening rate of 4 Hz. This method of torch diagnostics can be helpful for future studies and development of pulsating combustion control systems. © 2017 Author(s)

Systems biology analysis of the WOX5 gene and its functions in the root stem cell niche

WUSCHEL RELATED HOMEOBOX 5 (WOX5) gene encodes the transcription factor, which is one of the key regulators, maintaining structure and functioning of the stem cell niche in plant root tips. Protein WOX5 is expressed in the quiescent center of the root apical meristem, preventing differentiation of columella initials and altogether with SCR, SHR, PLT1 and PLT2 participating in the control of differentiation of other root meristem initials. However, the details of WOX5 functioning are unclear. The WOX5 protein belongs to WUSCHEL related homeobox (WOX) family, the founder of which is the transcription factor WUSCHEL (WUS) providing maintenance of the stem cell niche in the shoot apical meristem. WOX5 and WUS diverged from a common ancestor at the base of angiosperms, which resulted in a specialization of shoot and root stem cell niches. However, the problem of WOX5 structural and functional divergence during angiosperm evolution was poorly addressed. In this review we present a systems biology analysis of the WOX5 gene to reveal specific features of its evolution and functioning. To this end, we performed a phylogenetic analysis on 62 publicly available WOX5 amino acid sequences, generalized published data about WOX5 expression domain in Arabidopsis and other species and its role in development, integrated the results of experiments on identification of primary and secondary targets for this transcription factor. Data on possible mechanisms of direct and indirect regulation of WOX5 expression were discussed. Particularly, we performed the analysis of WOX5 promoter regions from 30 species. Possible direct regulators of the WOX5 gene expression were proposed based on the presence of putative binding sites for the candidate transcription factors in conserved WOX5 promoter regions

How Does Bilingualism Affect the Volume of Vocabulary in Senior Preschoolers?

Рассматривается влияние билингвизма на развитие активного и пассивного словарного запаса у детей старшего дошкольного возраста. Выборку составили 218 детей (средний возраст — 78,7 мес., SD — 5,87), живущих в Республике Саха (Якутия), из которых русскоязычных монолингвов 137 чел., якутско-русских билингвов — 81 чел. (на основании опроса воспитателей). Было выявлено, что билингвизм является негативным фактором для развития как пассивного словаря ребенка, так и его вербальной беглости. Однако благодаря развитию регуляторных функций этот негативный эффект может быть преодолен.The authors examine the influence of bilingualism on the development of active and passive vocabulary in senior preschool children. The sample consisted of 218 children (average age — 78,7 months, SD — 5,87) living in the Republic of Sakha (Yakutia), of which 137 are Russian-speaking monolinguals, 81 are Yakut-Russian bilinguals (based on a questionnaire of educators). It was found that bilingualism is a negative factor for the development of both a child’s passive vocabulary and his/her verbal fluency. However, due to the development of regulatory functions, this negative effect can be overcome.Исследование поддержано грантом РНФ № 21‑18‑00581

The mean-value theorem for elliptic operators on stratified sets

yesIn this paper, an analog of the mean-value theorem for harmonic functions is proved for an elliptic operator on the stratified set of “stratified” spheres whose radius is sufficiently small. In contrast to the classical case, the statement of the theorem has the form of a special differential relationship between the mean values over different parts of the sphere. The result is used to prove the strong maximum principleBelgorod State Universit

A necessary condition for an extremum on a stratified set

In this paper, on a connected set composed of finitely many convex polyhedra of different dimensions, we introduce a special (stratified) measure and define a divergence operator (as the flow density of the tangent vector field) and a Laplacian on smooth functionsyesBelgorod State Universit

A necessary condition for an extremum on a stratified set

yesIn this paper, on a connected set composed of finitely many convex polyhedra of different dimensions, we introduce a special (stratified) measure and define a divergence operator (as the flow density of the tangent vector field) and a Laplacian on smooth functionsBelgorod State Universit

Maximum principle for subharmonic functions on a stratified set

yesThe strong maximum principle is proved for solutions of the inequality ∆u≥0 on a stratified setBelgorod State Universit

The mean-value theorem for elliptic operators on stratified sets

In this paper, an analog of the mean-value theorem for harmonic functions is proved for an elliptic operator on the stratified set of “stratified” spheres whose radius is sufficiently small. In contrast to the classical case, the statement of the theorem has the form of a special differential relationship between the mean values over different parts of the sphere. The result is used to prove the strong maximum principleyesBelgorod State Universit

Maximum principle for subharmonic functions on a stratified set

The strong maximum principle is proved for solutions of the inequality ∆u≥0 on a stratified setyesBelgorod State Universit