Polar mesosphere summer echoes: a comparison of simultaneous observations at three wavelengths

On 5 July 2005, simultaneous observations of Polar Mesosphere Summer Echoes (PMSE) were made using the EISCAT VHF (224 MHz) and UHF (933 MHz) radars located near Tromsø, Norway and the ALWIN VHF radar (53.5 MHz) situated on Andøya, 120 km SW of the EISCAT site. During the short interval from 12:20 UT until 12:26 UT strong echoes at about 84 km altitude were detected with all three radars. The radar volume reflectivities were found to be 4×10<sup>−13</sup> m<sup>−1</sup>, 1.5×10<sup>−14</sup> m<sup>−1</sup> and 1.5×10<sup>−18</sup> m<sup>−1</sup> for the ALWIN, EISCAT-VHF and UHF radars, respectively. We have calculated the reflectivity ratios for each pair of radars and have compared them to ratios obtained from the turbulence-theory model proposed by Hill (1978a). We have tested different values of the turbulent energy dissipation rate ε and Schmidt number <i>S<sub>c</sub></i>, which are free parameters in the model, to try to fit theoretical reflectivity ratios to the experimental ones. No single combination of the parameters ε and <i>S<sub>c</sub></i> could be found to give a good fit. Spectral widths for the EISCAT radars were estimated from the spectra computed from the autocorrelation functions obtained in the experiment. After correction for beam-width broadening, the spectral widths are about 4 m/s for the EISCAT-VHF and 1.5–2 m/s for the UHF radar. However, according to the turbulence theory, the spectral widths in m/s should be the same for both radars. We also tested an incoherent scatter (IS) model developed by Cho et al. (1998), which takes into account the presence of charged aerosols/dust at the summer mesopause. It required very different sizes of particles for the EISCAT-VHF and UHF cases, to be able to fit the experimental spectra with model spectra. This implies that the IS model cannot explain PMSE spectra, at least not for monodisperse distributions of particles

Renormalized theory of the ion cyclotron turbulence in magnetic field--aligned plasma shear flow

The analytical treatment of nonlinear evolution of the shear-flow-modified current driven ion cyclotron instability and shear-flow-driven ion cyclotron kinetic instabilities of magnetic field--aligned plasma shear flow is presented. Analysis is performed on the base of the nonlinear dispersion equation, which accounts for a new combined effect of plasma turbulence and shear flow. It consists in turbulent scattering of ions across the shear flow with their convection by shear flow and results in enhanced nonlinear broadening of ion cyclotron resonances. This effect is found to lead to the saturation of ion cyclotron instabilities as well as to the development of nonlinear shear flow driven ion cyclotron instability. 52.35.RaComment: 21 page

Quantitative relation between PMSE and ice mass density

Radar reflectivities associated with Polar Mesosphere Summer Echoes (PMSE) are compared with measurements of ice mass density in the mesopause region. The 54.5 MHz radar Moveable Atmospheric Radar for Antarctica (MARA), located at the Wasa/Aboa station in Antarctica (73° S, 13° W) provided PMSE measurements in December 2007 and January 2008. Ice mass density was measured by the Solar Occultation for Ice Experiment (SOFIE). The radar operated continuously during this period but only measurements close to local midnight are used for comparison, to coincide with the local time of the measurements of ice mass density. The radar location is at high geographic latitude but low geomagnetic latitude (61°) and the measurements were made during a period of very low solar activity. As a result, background electron densities can be modelled based on solar illumination alone. We find a close correlation between the time and height variations of radar reflectivity and ice mass density, at all PMSE heights, from 80 km up to 95 km. A quantitative expression relating radar reflectivities to ice mass density is found, including an empirical dependence on background electron density. Using this relation, we can use PMSE reflectivities as a proxy for ice mass density, and estimate the daily variation of ice mass density from the daily variation of PMSE reflectivities. According to this proxy, ice mass density is maximum around 05:00–07:00 LT, with lower values around local noon, in the afternoon and in the evening. This is consistent with the small number of previously published measurements and model predictions of the daily variation of noctilucent (mesospheric) clouds and in contrast to the daily variation of PMSE, which has a broad daytime maximum, extending from 05:00 LT to 15:00 LT, and an evening-midnight minimum

Отражение идентичности русских через распознавание автоэтноимпликатур (на примере анализа автоэтноимпликатур о русском разговоре / беседе)

The article is devoted to the study of the problem of national identity of modern Russian people through its reflection in the Russian language. The consideration of the problem of national identity is connected with the question of who can be attributed to the Russians today. It is believed that one of the key conditions for the formation of a national-cultural identity is the assimilation of the values and norms of its sociocultural community, which can be reflected in language in the form of stable expressions (proverbs, sayings, idioms, etc.), and in the form of ethno-implicatures ( auto-ethno-implicatures). If the stable expressions characterizing a particular nation (ethnic group, nation), including Russians, are studied well enough, then research on ethno-implicatures (especially auto-ethno-implicatures) is clearly insufficient. It is assumed that through the recognition of auto-ethno-implicatures, it is possible to determine the current national values of modern Russians, as well as to trace their changes. This is possible, in our opinion, with the help of a series of linguistic and sociolinguistic experiments. The article presents the results of a linguistic experiment aimed at recognizing auto-ethno-implicatures of one of the key values / traits of Russians, according to researchers, – the sincerity of relations, the need for close social relations, expressed in such a thing as “Russian conversation”.Настоящая статья посвящена изучению проблемы национальной идентичности современных русских людей через её отражение в русском языке. Рассмотрение проблемы национальной идентичности связано с вопросом о том, кого сегодня можно отнести к русским. Считается, что одним из ключевых условий формирования национально-культурной идентичности является усвоение ценностей и норм своей социокультурной общности, которые в языке могут отражаться как в виде устойчивых выражений (пословиц, поговорок, фразеологизмов и т. п.), так и в форме этноимпликатур (автоэтноимпликатур). Если устойчивые выражения, характеризующие тот или иной народ (этнос, нацию), в том числе и русских, изучены достаточно хорошо, то исследований этноимпликатур (особенно автоэтноимпликатур) пока явно недостаточно. Предполагается, что через распознавание автоэтноимпликатур можно определить действующие национальные ценности современных русских, а также проследить их изменения. Это возможно сделать, на наш взгляд, с помощью серии лингвистических и социолингвистических экспериментов. В статье приводятся результаты лингвистического эксперимента, направленного на распознавание автоэтноимпликатуры одной из ключевых ценностей / черт русских, по мнению исследователей, – душевности отношений, потребности в близких социальных отношениях, выраженной в таком явлении, как «русский разговор / беседа»

Diagnostics of mineral nutrition of carrot and red beet at organic and mineral fertilization systems

Relevance. In the transition to highly productive and environmentally friendly, in particular, organic agriculture and production of safe and high-quality products, which is a priority direction of strategies of scientific and technological development of the Russian Federation, one of the necessary links is the creation and control of optimal conditions of plant nutrition, i.e. provision of plants with nutrients in the right combination throughout the vegetation. Achievement of such conditions is possible through soil and plant nutrition diagnostics, which in turn allows to establish the ability of crops to assimilate nutrients from the soil and adjust the doses of mineral fertilisers as top dressings.Material and Methods. On alluvial meadow soil in the conditions of the non-Black Earth region of Russia, the effectiveness of root feeding with macronutrients (NPK) was studied according to the results of plant and soil diagnostics of table root crops nutrition when grown on organic and mineral fertiliser systems. Plant and soil diagnostics of mineral nutrition was carried out according to the methods of Zerling V.V. (1990) and Magnitsky K.P. (1972). Two crops were tested during the experiment: red beet variety Mulatka and garden carrot variety Losinoostrovskaya 13.Results and Discussion. Root fertilizers on the basis of nutrition diagnostics on the basis of soil and leaf petiole analysis made significant changes in the dynamics of basic nutrients in the soil, there was an increase in nitrate nitrogen and mobile potassium in comparison with the control variant, with natural soil supply of mobile phosphorus (more than 250 mg/kg), which had a positive effect on the root nutrition of plants. At the main application of mineral and organic (biocompost BIUD) fertilizers, root fertilizers according to nutrition diagnostics the carrot yield 51,2-63,9 t/ha with standard 87,4- 94,6%, red beet 41,7-54,2 t/ha with standard 80,7-92,3% were obtained. Root feeding of carrots by soil diagnostics N52K14 on the background of biocompost gave 24.9% increase to the control, by plant diagnostics N17 gave 16.6%; red beet by soil diagnostics N65K45 – 30% increase, by plant diagnostics N54K30 – 23.7

Semantic features of the phraseological units with the component light within the artistic discourse

Conduct lexical and semantic analysis on the concept light in the artistic discourse of postmodern fictio

Fresnel scatter revisited-comparison of 50 MHz radar and radiosondes in the Arctic, the Tropics and Antarctica

High-resolution radiosondes and calibrated radars operating close to 50 MHz, are used to examine the relationship between the strength of radar scatter and refractive index gradient. Three radars are used, in Kiruna in Arctic Sweden, at Gadanki in southern India and at the Swedish/Finnish base Wasa/Aboa in Queen Maud Land, Antarctica. Calibration is accomplished using the daily variation of galactic noise measured at each site. Proportionality between radar scatter strength and the square of the mean gradient of potential refractive index, M2, is found in the upper troposphere and lower stratosphere at all three sites, confirming previously reported results from many VHF radars. If the radar scatter is interpreted as Fresnel scatter, the constant of proportionality between radar scatter and M2 is found to be the same, within the calibration uncertainties, for all three radars. The radiosondes show evidence of distinct layering with sharp gradients, extending over 10s of kilometers horizontally, but the scatter is found to be two orders of magnitude weaker than would be expected from true Fresnel scatter from such layers. Using radar reflectivities resolved to a few 100 ms, we show that this is due to strong temporal variability in the scattering conditions, possibly due to undulations of the scattering layers. The constancy of the radar scatter – M2 relationship between the different sites suggests an unexpected uniformity in these perturbations between very different regions of the globe

SEMANTIC FEATURES OF THE PHRASEOLOGICAL UNITS WITH THE COMPONENT LIGHT THE WITHIN ARTISTIC DISCOURSE

Purpose: To conduct lexical and semantic analysis on the concept light in the artistic discourse of postmodern fiction. Methodology: In this research, comparative method, search for synonyms, continuous sampling and seminal analysis are used. Main Findings: As a result, it becomes obvious that the boundaries of the artistic concepts are extremely blurred and much wider than the boundaries of the corresponding non-artistic concepts. In conclusion, the concept light is frequently used in English artistic discourses, i.e. significant in the culture, and a special status in the semantic space of the concept light has the meaning of knowledge and information. Applications: The study results can be used by students and universities. Novelty/Originality: In this research, a model of the semantic features of the phraseological units with the component light is presented in a comprehensive and complete manner

Polynomial formulations as a barrier for reduction-based hardness proofs

The Strong Exponential Time Hypothesis (SETH) asserts that for every $\varepsilon>0$ there exists $k$ such that $k$-SAT requires time $(2-\varepsilon)^n$. The field of fine-grained complexity has leveraged SETH to prove quite tight conditional lower bounds for dozens of problems in various domains and complexity classes, including Edit Distance, Graph Diameter, Hitting Set, Independent Set, and Orthogonal Vectors. Yet, it has been repeatedly asked in the literature whether SETH-hardness results can be proven for other fundamental problems such as Hamiltonian Path, Independent Set, Chromatic Number, MAX-$k$-SAT, and Set Cover. In this paper, we show that fine-grained reductions implying even $\lambda^n$-hardness of these problems from SETH for any $\lambda>1$, would imply new circuit lower bounds: super-linear lower bounds for Boolean series-parallel circuits or polynomial lower bounds for arithmetic circuits (each of which is a four-decade open question). We also extend this barrier result to the class of parameterized problems. Namely, for every $\lambda>1$ we conditionally rule out fine-grained reductions implying SETH-based lower bounds of $\lambda^k$ for a number of problems parameterized by the solution size $k$. Our main technical tool is a new concept called polynomial formulations. In particular, we show that many problems can be represented by relatively succinct low-degree polynomials, and that any problem with such a representation cannot be proven SETH-hard (without proving new circuit lower bounds)