A physically motivated toy model for the BH-spheroid coevolution

We present a summary of the results obtained with a time-dependent, one-zone toy model aimed at exploring the importance of radiative feedback on the co-evolution of massive black holes (MBHs) at the center of stellar spheroids and their stellar and gaseous components. We consider cosmological infall of gas as well as the mass and energy return for the evolving stellar population. The AGN radiative heating and cooling are described by assuming photoionization equilibrium of a plasma interacting with the average quasar SED. Our results nicely support a new scenario in which the AGN accretion phase characterized by a very short duty-cycle (and now common in the Universe) is due to radiative feedback. The establishment of this phase is recorded as a fossil in the Magorrian and Mbh-sigma relations.Comment: 2 pages. Proceedings of the MPA/MPE/ESO/USM Conference "Growing Black Holes: accretion in a cosmological context", ESO Astrophysics Symposia, A. Merloni, S. Nayakshin and R. Sunyaev ed

A hard X-ray survey of the Crux Galactic spiral arm tangent. A catalog of sources

This work is part of a large solid angle hard X-ray survey. We analized a number of observations by the IBIS telescope aboard the INTEGRAL observatory covering the Crux Galactic spiral arm tangent. We have detected 46 hard X-ray sources, with 15 of them being new. Among the identified sources there are 12 AGNs, 11 HMXBs, 6 LMXBs and 2 active stars. 13 sources remain unidendified.Comment: Accepted for publication in Astronomy Letter

High-frequency oscillations in low-dimensional conductors and semiconductor superlattices induced by current in stack direction

A narrow energy band of the electronic spectrum in some direction in low-dimensional crystals may lead to a negative differential conductance and N-shaped I-V curve that results in an instability of the uniform stationary state. A well-known stable solution for such a system is a state with electric field domain. We have found a uniform stable solution in the region of negative differential conductance. This solution describes uniform high-frequency voltage oscillations. Frequency of the oscillation is determined by antenna properties of the system. The results are applicable also to semiconductor superlattices.Comment: 8 pages, 3 figure

Organizational aspects of neurorehabilitation at the outpatient stage

The study was aimed to evaluate the effectiveness of IRP implementation in patients of a specialized clinic providing long-term care to neurological and neurosurgical patients. Material and methods. The study was conducted in 2020-2021. on the basis of the MC "Expert Health" (Odessa, Ukraine). 83 patients undergoing neurorehabilitation program were examined. The correspondence of the fulfillment of key rehabilitation tasks in terms of time and quality was assessed. Additionally, the level of motivation and compliance of the patient was assessed using the MOT-Q questionnaires (for patients with previous TBI (n = 13), SRMS (for patients with stroke (n = 54) and with SRQ-E (for patients with other types of neurological pathology (n = 16). The overall level of compliance was assessed using the General Rehabilitation Adherence Scale (GRAS). The level of safety was assessed according to the following criteria: the presence of FAST certificates for personnel, a system for monitoring vital functions, equipment and consumables for the provision of emergency care. Statistical processing was carried out by methods of variance and correlation analysis, using the MedCalc 1.3 software. Results. There were not recorded any significant violations of safety principles in the provision of rehabilitation assistance in the certification of personnel according to FAST. The frequency of detecting cases of improper implementation of IRP did not exceed 6.0% (5 cases out of 83 analyzed). When assessing the relationship between the effectiveness of IRP and the level of compliance, a strong positive correlation was found - r = 0.78 Conclusion. 1. Provision of rehab services for neurological patients in the long term requires coordination of the actions of specialists at the intra-, inter-, and transdisciplinary levels. 2. A necessary condition for the functioning of a multidisciplinary team in the provision of rehabilitation care is certification of staff in the BLS systems - for allied health specialists and ACLS for physicians. 3. The effectiveness of IRP depends on the patient's compliance level (r = 0.78). 4. For the continuity of the rehabilitation process, it is necessary to involve relatives and facilitate their training in the basics of "home" rehabilitation

Optical Identifications of Five INTEGRAL Hard X-ray Sources in the Galactic Plane Region

The results of optical identifications of five hard X-ray sources in the Galactic plane region from the INTEGRAL all-sky survey are presented. The X-ray data on one source (IGRJ20216+4359) are published for the first time. The optical observations were performed with 1.5-m RTT-150 telescope (TUBITAK National Observatory, Antalya, Turkey) and 6-m BTA telescope (Special Astrophysical Observatory, Nizhny Arkhyz, Russia). A blazar, three Seyfert galaxies, and a high-mass X-ray binary are among the identified sources.Comment: 7 pages, 10 figures, Astronomy Letters, v. 34, p. 65

Observing scattered X-ray radiation from gamma-ray bursts: a way to measure their collimation angles

There are observational facts and theoretical arguments for an origin of gamma-ray bursts in molecular clouds in distant galaxies. If this is true, one could detect a significant flux of GRB prompt and early afterglow X-ray radiation scattered into our line of sight by the molecular and atomic matter located within tens of parsecs of the GRB site long after the afterglow has faded away. The scattered flux directly measures the typical density of the GRB ambient medium. Furthemore, if the primary emission is beamed, the scattered X-ray flux will be slowly decreasing for several months to years before falling off rapidly. Therefore, it should be possible to estimate the collimation angle of a burst from the light curve of its X-ray echo and a measured value of the line-of-sight absorption column depth. It is shown that detection of such an echo is for the brightest GRBs just within the reach of the Chandra and XMM-Newton observatories.Comment: 6 pages, 2 figures. Accepted for publication in Astronomy and Astrophysic

Several New Active Galactic Nuclei Among X-ray Sources Detected by INTEGRAL and SWIFT Observatories

We present the results of the optical identifications of a set of X-ray sources from the all-sky surveys of INTEGRAL and SWIFT observatories. Optical data were obtained with Russian-Turkish 1.5-m Telescope (RTT150). Nine X-ray sources were identified as active galactic nuclei (AGNs). Two of them are hosted by nearby, nearly exactly edge-on, spiral galaxies MCG -01-05-047 and NGC 973. One source, IGR J16562-3301, is most probably BL Lac object (blazar). Other AGNs are observed as stellar-like nuclei of spiral galaxies, with broad emission lines in their spectra. For the majority of our hard X-ray selected AGNs, their hard X-ray luminosities are well-correlated with the luminosities in [OIII],5007 optical emission line. However, the luminosities of some AGNs deviate from this correlation. The fraction of these objects can be as high as 20%. In particular, the flux in [OIII] line turns to be lower in two nearby edge-on spiral galaxies, which can be explained by the extinction in their galactic disks.Comment: 9 pages, 3 figures, accepted for publication in Astronomy Letters, the original text in Russian can be found at http://hea.iki.rssi.ru/~rodion/poptid.pd