Frequency spectra of short-period variations of cosmic ray

Frequency spectra for different periods of solar activity were calculated by 5-minutes data of a neutron super-monitor, (altitude 3340 m, cutoff rigidity is 6, 7 GV, counting rate is about 4.5.10 per hour). It was shown that shifting of the spectrum power from low-frequency range to high-frequency range takes place from minimum to maximum of the solar activity. It was reliably distinguished the peak with 160-minutes period coincided with the period of the Sun's atmosphere oscillation and some types of geomagnetic pulsation by the method of accumulation of the frequency spectra. It was conducted the comparison of cosmic ray spectra with spectra of geomagnetic field for the same point of the registration and at the same period

Activity of cholinesterases of blood and heart in rats of different sex and age during muscular loads and hypokinesia

The activity of acetylcholinesterase (Ache) and butyrilcholinesterase (Bche) in the blood and the heart of 3 and 13 month old control male rats is considerably lower than in female rats. In 25 month old rats, no sex differences in the Ache and Bche were revealed in the heart. In 3 and 13 month old male and female rats, under conditions of muscular exercises, the Ache and Bche activity is lower, and in hypokinetic male rats -- higher than that in respective control animals. In all the rats, irrespective of sex, age, and motor conditions, Ache and Bche activity tended to decrease from the sinoatrial node to the heart apex

Leadership potential of professional teacher associations in Russia: Formation of middle leaders

This research study is aimed at investigating distributed leadership practices in the Russian school system, of which professional teacher associations (PTA) constitute a distinct feature. In particular, we set out to investigate the PTA leadership potential, as well as the role and specific personal characteristics of middle leaders in the Russian school education system. These associations are formed by the school administration on the basis of subject areas, bringing together teachers of maths, history, etc. Teachers join PTAs on a voluntarily basis. The key function of such organisations consists in the implementation of innovative educational approaches and techniques. In order to analyse their leadership potential, we carried out a sociological survey among the employees of high-profile secondary schools (gymnasiums and lyceums) situated in the major Russian city of Ekaterinburg. The research methodology comprised structured interviews with 110 respondents, along with in-depth interviews with 2 school directors, 4 school deputy directors and 6 heads of professional teacher associations. Our results show that the fundamentals and principles of distributed leadership are actively implemented in Ekaterinburg schools. The school administrations encourage the creation of professional teacher associations grouped around subject areas, delegating to these structural units the functions of improving the quality of teaching the respective subjects and disseminating educational innovations, at the same time as fulfilling the requirements of the state and regional education authorities. Such associations are headed by middle leaders, who are nominated by their colleagues and whose candidacy is approved by school seniors, taking into account their professional achievements, experience of leading pedagogical innovations and the presence of the right personal qualities necessary for productive collaborative work. These people perform the role of mediators, operating at the interface between various levels within the school. Although viewed as a school’s personnel reserve for the positions of principals and head teachers, our respondents consider themselves to be ‘more teachers’ or ‘innovators in education’ than administrators. The development of the leadership qualities of such professionals in the Russian school system is shown to be hindered by a ‘glass ceiling’ – a certain limit in their career growth. This discouraging factor results in some middle school leaders searching for professional self-realization opportunities outside the school system, in the spheres of business, science or culture that are believed to provide more opportunities for self-advancement. © 2019 National Research University Higher School of Economics. All rights reserved

Phase connecting multi-epoch radio data for the ultracool dwarf TVLM 513-46546

Context. Radio data obtained for the ultracool dwarf TVLM 513-46546 has indicated a rotation period of ≈1.96 h via regular radio pulses, but how stable is this period. This has major implications regarding the stability of the magnetic field structures responsible for the radio emission from the ultracool dwarf. Aims. The aim of the present work is to investigate the stability of this rotation period using two datasets taken ≈40 days apart, some 12 months after the first report of periodical pulses in the radio data. Methods. Here we use a Bayesian analysis method which is a statistical procedure that endeavours to estimate the parameters of an underlying model probability distribution based on the observed data. Results. Periodical pulses are detected in datasets taken in April and June 2007, with the pulses being confined to a narrow range in the rotation period. This is in contradiction to a previous report of only aperiodic activity in the April 2007 dataset, while in fact both datasets have a periodic signal with a false alarm probability ≪ 10^-12. These two datasets are then used to derive a more accurate period (previously determined to be 1.96 h) of 1.96733 ± 0.00002 h. Conclusions. The similarly in the burst structure in datasets taken several weeks apart point towards the stability of an electric field structure which is somehow generated and sustained within the magnetosphere of the ultracool dwarf. The derived period of 1.96733 h is consistent with the period derived via radio and optical data taken some 12 months prior to the present observations and implies the near phase constancy of the pulsed emission. This suggest the presence of stable large-scale magnetic fields on timescales of more than 1 year. The characteristics of the pulses suggest that they are produced by the electron cyclotron maser (ECM) instability

Methods of the determination of inorganic arsenic species by stripping voltammetry in weakly alkaline media

Two methods are considered for the direct determination of trace amounts of As(III) and As(V) in solutions by stripping voltammetry (SVA) using an ensemble of gold microelectrodes (Au-MEA) previously developed by the authors of this paper. In both methods, analyzing a mixture of As(III) and As(V), analysts first record an SVA signal of As(III) in a supporting Na2SO3 electrolyte. To record an analytical SVA signal of As(V), in the first method one should use the reduction of As(V) to As(III) on the surface of an Au-MEA catalyzed by the system Mn(II)/Mn(0) and followed by the formation of As(0) and its anode dissolution. In the second method, the photoreduction of As(V) to As(III) in a Na2SO3 solution is conducted under UV irradiation followed by the reduction of As(III) to As(0) and its electrooxidation on Au-MEA. The two methods are compared taking into account their performance characteristics and interfering ions. To improve the reliability of the results of analysis at an insignificant increase in its cost, we propose the consecutive use of both methods. The procedures are simple and rapid, do not require the removal of dissolved oxygen or toxic reactants, and can be used for the analysis of aqueous solutions at the place of sampling. The results of analyses of real objects, snow, river water, and process solutions are presented

Comparative analysis of two formation scenarios of bursty radio emission from ultracool dwarfs

Recently, a number of ultracool dwarfs have been found to produce periodic radio bursts with high brightness temperature and polarization degree; the emission properties are similar to the auroral radio emissions of the magnetized planets of the Solar System. We simulate the dynamic spectra of radio emission from ultracool dwarfs. The emission is assumed to be generated due to the electron-cyclotron maser instability. We consider two source models: the emission caused by interaction with a satellite and the emission from a narrow sector of active longitudes; the stellar magnetic field is modeled by a tilted dipole. We have found that for the dwarf TVLM 513-46546, the model of the satellite-induced emission is inconsistent with the observations. On the other hand, the model of emission from an active sector is able to reproduce qualitatively the main features of the radio light curves of this dwarf; the magnetic dipole seems to be highly tilted (by about 60 degrees) with respect to the rotation axis.Comment: Accepted for publication in Ap

Sporadic Long-term Variability in Radio Activity from a Brown Dwarf

Radio activity has been observed in a large variety of stellar objects, including in the last few years, ultra-cool dwarfs. To explore the extent of long-term radio activity in ultra-cool dwarfs, we use data taken over an extended period of 9 hr from the Very Large Array of the source 2MASS J05233822-1403022 in September 2006, plus data taken in 2004. The observation taken in September 2006 failed to detect any radio activity at 8.46 GHz. A closer inspection of earlier data reveals that the source varied from a null detection on 3 May 2004, to $\approx$95 $\mu$Jy on 17 May 2004, to 230 $\mu$Jy on 18 June 2004. The lack of detection in September 2006 suggests at least a factor of ten flux variability at 8.46 GHz. Three short photometric runs did not reveal any optical variability. In addition to the observed pulsing nature of the radio flux from another ultra-cool source, the present observations suggests that ultra-cool dwarfs may not just be pulsing but can also display long-term sporadic variability in their levels of quiescent radio emission. The lack of optical photometric variability suggests an absence of large-scale spots at the time of the latest VLA observations, although small very high latitude spots combined with a low inclination could cause very low amplitude rotational modulation which may not be measurable. We discuss this large variability in the radio emission within the context of both gyrosynchrotron emission and the electron-cyclotron maser, favoring the latter mechanism.Comment: 7 pages, 2 figures, 1 table, accepted for publication in A&A Letter

Methods to provide supply and demand balance on the regional industrial labour market (By Qualifications)

This article deals with the problem of professional and qualification balance on the regional labor market and the ways to resolve them. It is shown that the Republic of Tatarstan labor market is characterized by lack of balance; it abounds in highly qualified professionals especially in humanities, and lacks qualified workers. The author develops a method, which can provide supply and demand balance on the industrial labor market of the region. He also shows different interaction patterns between regional authorities on the one part, and factories and educational institutions on the other part, in order to provide this balance

Modelling the radio pulses of an ultracool dwarf

<b>Context:</b> Recently, unanticipated magnetic activity in ultracool dwarfs (UCDs, spectral classes later than M7) has emerged from a number of radio observations. The highly (up to 100%) circularly polarized nature and high brightness temperature of the emission have been interpreted as requiring an effective amplification mechanism of the high-frequency electromagnetic waves − the electron cyclotron maser instability (ECMI). <p/><b>Aims:</b> We aim to understand the magnetic topology and the properties of the radio emitting region and associated plasmas in these ultracool dwarfs, interpreting the origin of radio pulses and their radiation mechanism. <p/><b>Methods:</b> An active region model was built, based on the rotation of the UCD and the ECMI mechanism. <p/><b>Results:</b> The high degree of variability in the brightness and the diverse profile of pulses can be interpreted in terms of a large-scale hot active region with extended magnetic structure existing in the magnetosphere of TVLM 513-46546. We suggest the time profile of the radio light curve is in the form of power law in the model. Combining the analysis of the data and our simulation, we can determine the loss-cone electrons have a density in the range of 1.25 × 105−5 × 105 cm-3 and temperature between 107 and 5 × 107 K. The active region has a size <1 RJup, while the pulses produced by the ECMI mechanism are from a much more compact region (e.g. ~0.007 RJup). A surface magnetic field strength of ≈7000 G is predicted. <p/><b>Conclusions:</b> The active region model is applied to the radio emission from TVLM 513-46546, in which the ECMI mechanism is responsible for the radio bursts from the magnetic tubes and the rotation of the dwarf can modulate the integral of flux with respect to time. The radio emitting region consists of complicated substructures. With this model, we can determine the nature (e.g. size, temperature, density) of the radio emitting region and plasma. The magnetic topology can also be constrained. We compare our predicted X-ray flux with Chandra X-ray observation of TVLM 513-46546. Although the X-ray detection is only marginally significant, our predicted flux is significantly lower than the observed flux. Further multi-wavelength observations will help us better understand the magnetic field structure and plasma behavior on the ultracool dwarf