95 research outputs found
Tactics of forming a system of financial indicators of the enterprises in the operational aspects
© 2015, Mediterranean Center of Social and Educational Research. All rights reserved. The article contains a number of theoretical and methodological developments and practical recommendations for the tactics of forming financial indicators and to ensure their sustainable basis the financial condition, proposed modeling scheme of financial indicators and indicators with the recommended performance standards for the level of the financial condition of the operational aspect
Blueshifted galaxies in the Virgo Cluster
We examine a sample of 65 galaxies in the Virgo cluster with negative radial
velocities relative to the Local Group. Some features of this sample are
pointed out. All of these objects are positioned compactly within a virial zone
of radius 6{\deg} in the cluster, but their centroid is displaced relative to
the dynamic center of the cluster, M87, by 1.1{\deg} to the northwest. The
dwarf galaxies in this sample are clumped on a scale of ~10' (50 kpc). The
observed asymmetry in the distribution of the blueshifted galaxies may be
caused by infall of a group of galaxies around M86 onto the main body of the
cluster. We offer another attempt to explain this phenomenon, assuming a mutual
tangential velocity of ~300 km/s between the Local Group and the Virgo cluster
owing to their being repelled from the local cosmological void.Comment: 10 pages, 4 figures, 1 table. Published in Astrophysics, Vol. 53, No.
1, pp. 32-41, 201
NGC 7468: a galaxy with an inner polar disk
We present our spectroscopic observations of the galaxy NGC 7468 performed at
the 6-m Special Astrophysical Observatory telescope using the UAGS long-slit
spectrograph, the multipupil fiber spectrograph MPFS, and the scanning
Fabry-Perot interferometer (IFP). We found no significant deviations from the
circular rotation of the galactic disk in the velocity field in the regions of
brightness excess along the major axis of the galaxy (the putative polar ring).
Thus, these features are either tidal structures or weakly developed spiral
arms. However, we detected a gaseous disk at the center of the galaxy whose
rotation plane is almost perpendicular to the plane of the galactic disk. The
central collision of NGC 7468 with a gas-rich dwarf galaxy and their subsequent
merging seem to be responsible for the formation of this disk.Comment: 8 pages, 6 figures, accepted in Astronomy Letters, 2004, vol 30., N
9, p. 58
Inner Polar Rings and Disks: Observed Properties
A list of galaxies with inner regions revealing polar (or strongly inclined
to the main galactic plane) disks and rings is compiled from the literature
data. The list contains 47 galaxies of all morphological types, from E to Irr.
We consider the statistics of the parameters of polar structures known from
observations. The radii of the majority of them do not exceed 1.5 kpc. The
polar structures are equally common in barred and unbarred galaxies. At the
same time, if a galaxy has a bar (or a triaxial bulge), this leads to the polar
disk stabilization - its axis of rotation usually coincides with the major axis
of the bar. More than two thirds of all considered galaxies reveal one or
another sign of recent interaction or merging. This fact indicates a direct
relation between the external environment and the presence of an inner polar
structure.Comment: 12 pages, 3 figures, accepted to Astrophysical Bulletin. Minor
changes and corrections are still possibl
Ultra-Compact Dwarfs in the Coma Cluster
We have undertaken a spectroscopic search for ultra compact dwarf galaxies
(UCDs) in the dense core of the dynamically evolved, massive Coma cluster as
part of the HST/ACS Coma Cluster Treasury Survey. UCD candidates were initially
chosen based on color, magnitude, degree of resolution within the ACS images,
and the known properties of Fornax and Virgo UCDs. Follow-up spectroscopy with
Keck/LRIS confirmed 27 candidates as members of the Coma Cluster, a success
rate > 60% for targeted objects brighter than M_R = -12. Another 14 candidates
may also prove to be Coma members, but low signal-to-noise spectra prevent
definitive conclusions. An investigation of the properties and distribution of
the Coma UCDs finds these objects to be very similar to UCDs discovered in
other environments. The Coma UCDs tend to be clustered around giant galaxies in
the cluster core and have colors/metallicity that correlate with the host
galaxy. With properties and a distribution similar to that of the Coma cluster
globular cluster population, we find strong support for a star cluster origin
for the majority of the Coma UCDs. However, a few UCDs appear to have stellar
population or structural properties which differentiate them from the old star
cluster populations found in the Coma cluster, perhaps indicating that UCDs may
form through multiple formation channels.Comment: 40 pages, 23 figures, accepted for publication in Ap
Norbornadiene as a Universal Substrate for Organic and Petrochemical Synthesis
A wide range of rare polycyclic hydrocarbons can be obtained through catalytic processes involving norbornadiene (NBD). The problem of selectivity is crucial for such reactions. The feasibility of controlling
selectivity and reaction rate has been shown for cyclic dimerization, co-dimerization, isomerization and allylation of NBD. Kinetic rules have been scrutinized. Consistent mechanisms have been proposed. Factors
affecting directions of the reactions and allowing us to obtain individual stereoisomers quantitatively, have been established. A series of novel unsaturated compounds has been synthesized; they incorporate a set of double bonds with different reactivity and can find an extremely wide range of applications
Microwave-Assisted synthesis and evaluation of antibacterial activity of novel 6-fluoroaryl-[1,2,4]triazolo[1,5-A]pyrimidines
A series of 6-fluoroaryl substituted [1,2,4]triazolo[1,5-A]pyrimidines have been synthesized by using the microwave-Assisted Suzuki cross-coupling reaction from readily available 6-bromo-[1,2,4]triazolo[1,5-A]pyrimidine. The antimicrobial activity of new compounds has been evaluated in vitro against Mycobacterium tuberculosis H37Rv and gram-negative (Neisseria gonorrhoeae ATCC 49226) bacteria. © ARKAT-USA, Inc
Image-Subtraction Photometry of the Globular Cluster M3: identification of new double-mode RR Lyrae stars
We have applied the image subtraction method to the M3 dataset previously
analyzed by Corwin & Carney (2001; CC01). The new analysis produced light
curves and periods for 15 variables, bringing to 222 the total number of RR
Lyrae stars in CC01 M3 dataset. We have identified three new candidate
double-mode (RRd) variables (V13, V200, and V251) in M3. Of the newly
discovered RRd's V13 is unusual in that it has the fundamental as the dominant
pulsation mode. Two of the new candidate RRd's (V13 and V200) have period
ratios as low as 0.738-0.739. They lie separated from all previously known
RRd's in the Petersen diagram, in positions implying a large spread in mass
and/or, less likely, in heavy element mass fraction, among the M3 horizontal
branch (HB) stars. We explore mass transfer and helium enhancement as possible
explanations for the apparent spread in HB masses. We also note that the masses
derived from the RRd analyses now favor little mass loss on the red giant
branch. V200 has changed its dominant pulsation mode from fundamental to first
overtone, while V251 has changed its dominant mode from first overtone to
fundamental in the interval 1992 to 1993. Together with M3-V166 this is the
first time that RRd variables are observed to switch their dominant pulsation
modes while remaining RRd's. The phenomenon is found to occur in a one year
time-span thus suggesting that these stars are undergoing a rapid evolutionary
phase, and that both redward and blueward evolution may take place among the HB
stars in M3. The unusual behavior of the M3 RRd's is discussed and compared to
that of the RRd's identified so far in globular clusters and in the field of
our and other Local Group galaxies. We find lack of correlation between the
presence of RRd variables and any of the cluster structural parameters.Comment: 38 pages, 16 figures, AJ in pres
Synthesis of novel [1,2,4]triazolo[1,5-b][1,2,4,5]tetrazines and investigation of their fungistatic activity
A series of novel [1,2,4]triazolo[1,5-b][1,2,4,5]tetrazines has been synthesized through oxidation reaction of the corresponding 3,6-disubstituted 1,2,4,5-tetrazines bearing amidine fragments. It is shown that the heterocyclic systems obtained can be modified easily at C(3) position in the reactions with aliphatic alcohols and amines. Also, the reactivity of [1,2,4]triazolo[1,5-b][1,2,4,5]tetrazines towards CH-active compounds has been studied. The obtained triazolo[1,5-b]annulated 1,2,4,5-tetrazines proved to be active in micromolar concentrations in vitro against filamentous anthropophilic and zooanthropophilic dermatophyte fungi (Trichophyton, Microsporum and Epidermofiton), which cause skin and its appendages (hair, nails) diseases. © 2022 Korotina et al.; licensee Beilstein-Institut.Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-15-2020-777; Ural Branch, Russian Academy of Sciences, UB RASThis work was supported by the Ministry of Education and Science of the Russian Federation (Agreement No. 075-15-2020-777).Analytical studies were carried out using equipment of the Center for Joint Use “Spectroscopy and Analysis of Organic Compounds”, located in Postovsky Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences. This work was supported by the Ministry of Education and Science of the Russian Federation (Agreement No. 075-15-2020-777)
The HST/ACS Coma Cluster Survey: V - Compact Stellar Systems in the Coma Cluster
The HST ACS Coma Cluster Treasury Survey is a deep two passband imaging
survey of the nearest very rich cluster of galaxies, covering a range of galaxy
density environments. The imaging is complemented by a recent wide field
redshift survey of the cluster conducted with Hectospec on the 6.5m MMT. Among
the many scientific applications for this data are the search for compact
galaxies. In this paper, we present the discovery of seven compact (but quite
luminous) stellar systems, ranging from M32-like galaxies down to ultra-compact
dwarfs (UCDs)/dwarf to globular transition objects (DGTOs). We find that all
seven compact galaxies require a two-component fit to their light profile and
have measured velocity dispersions that exceed those expected for typical
early-type galaxies at their luminosity. From our structural parameter analysis
we conclude that three of the sample should be classified as compact
ellipticals or M32-like galaxies, the remaining four being less extreme
systems. The three compact ellipticals are all found to have old luminosity
weighted ages (> 12 Gyr), intermediate metallicities (-0.6 < [Fe/H] < -0.1) and
high [Mg/Fe] (> 0.25). Our findings support a tidal stripping scenario as the
formation mode of compact galaxies covering the luminosity range studied here.
We speculate that at least two early-type morphologies may serve as the
progenitor of compact galaxies in clusters.Comment: 23 pages, 11 figures, accepted for publication in MNRAS. Proof typos
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