3,855 research outputs found
Особистісні трансформації складових поведінкового компонента професійної діяльності правоохоронців
The author of the article has provided the results of the study of the features of personal transformations of the elements of behavioral component of law enforcement officers’ professional activity at the stage of training in higher educational institutions with specific learning conditions. The interdependent elements of behavioral component of a law enforcement officer’s professional activity have been singled out, namely: the adaptive potential of an individual, skills and behavioral self-regulation styles, individual and business qualities, mechanisms of psychological protection and coping-behavior strategies.
The author has diagnosed the features of strategies and models of coping behavior of law enforcement officers at different stages of professional training. So, in difficult life situations it is typical for freshmen to come into contact with others for decision-making. Despite this, they are able to take responsibility and solve problems independently, although they still need support from others. Second-year students tend to work together to achieve mutual goals that coincide and to avoid the risk of failure due to long-term analysis of solution options and possible consequences, they are prone to re-insurance and cautious actions. Third-year students seek support from others (family, friends, colleagues), have the ability to solve problematic, difficult situations with other people, are able to cooperate and behave combining inner strength and politeness to the environment. MA students use practically the same with third-year students a set of models of coping behavior, search for social support and interaction with people. However, they are more prone to cautious actions and weighed decisions than third-year students.
It has been determined that law enforcement officers at the stage of professional training are least of all inclined to use passive and asocial coping strategies. Thus, freshmen in difficult situations will not demonstrate caution and aggression, second-year students will not avoid difficulties and behave in asocial way, third-year students are also less likely to engage in antisocial and aggressive actions, and MA students are less likely to act aggressively and avoid solving problems.Представлены результаты исследования особенностей личностных трансформаций составляющих поведенческого компонента профессиональной деятельности правоохранителей на этапе обучения в учреждениях высшего образования со специфическими условиями обучения. Выделены взаимосвязанные составляющие поведенческого компонента профессиональной деятельности правоохранителя. Диагностировано, что в сложных ситуациях курсанты 1 и 3 курсов обучения используют достаточно широкий спектр просоциальных и активных стратегий копинг-поведения. Выяснено, что курсанты 2 курса обучения и слушатели магистратуры наряду с просоциальными действиями склонны к пассивному копинг-поведению.Подано результати дослідження особливостей особистісних трансформацій складових поведінкового компонента професійної діяльності правоохоронців на етапі навчання у закладах вищої освіти зі специфічними умовами навчання. Виокремлено взаємозалежні складові поведінкового компонента професійної діяльності правоохоронця. Діагностовано, що у складних ситуаціях курсанти 1 та 3 курсів навчання використовують досить широкий спектр просоціальних та активних стратегій копінг-поведінки. З’ясовано, що курсанти 2 курсу навчання та слухачі магістратури разом із просоціальними діями схильні до пасивної копінг-поведінки
A new species in the major malaria vector complex sheds light on reticulated species evolution
Complexes of closely related species provide key insights into the rapid and independent evolution of adaptive traits. Here, we described and studied Anopheles fontenillei sp.n., a new species in the Anopheles gambiae complex that we recently discovered in the forested areas of Gabon, Central Africa. Our analysis placed the new taxon in the phylogenetic tree of the An. gambiae complex, revealing important introgression events with other members of the complex. Particularly, we detected recent introgression, with Anopheles gambiae and Anopheles coluzzii, of genes directly involved in vectorial capacity. Moreover, genome analysis of the new species allowed us to clarify the evolutionary history of the 3La inversion. Overall, An. fontenillei sp.n. analysis improved our understanding of the relationship between species within the An. gambiae complex, and provided insight into the evolution of vectorial capacity traits that are relevant for the successful control of malaria in Africa
Breaking the Disk/Halo Degeneracy with Gravitational Lensing
The degeneracy between the disk and the dark matter contribution to galaxy
rotation curves remains an important uncertainty in our understanding of disk
galaxies. Here we discuss a new method for breaking this degeneracy using
gravitational lensing by spiral galaxies, and apply this method to the spiral
lens B1600+434 as an example. The combined image and lens photometry
constraints allow models for B1600+434 with either a nearly singular dark
matter halo, or a halo with a sizable core. A maximum disk model is ruled out
with high confidence. Further information, such as the circular velocity of
this galaxy, will help break the degeneracies. Future studies of spiral galaxy
lenses will be able to determine the relative contribution of disk, bulge, and
halo to the mass in the inner parts of galaxies.Comment: Replaced with minor revisions, a typo fixed, and reference added; 21
pages, 8 figures, ApJ accepte
The Next Generation Virgo Cluster Survey. VII. The intrinsic shapes of low-luminosity galaxies in the core of the Virgo cluster, and a comparison with the Local Group
(Abridged) We investigate the intrinsic shapes of low-luminosity galaxies in
the central 300 kpc of the Virgo cluster using deep imaging obtained as part of
the NGVS. We build a sample of nearly 300 red-sequence cluster members in the
yet unexplored magnitude range. The observed distribution of
apparent axis ratios is then fit by families of triaxial models with
normally-distributed intrinsic ellipticities and triaxialities. We develop a
Bayesian framework to explore the posterior distribution of the model
parameters, which allows us to work directly on discrete data, and to account
for individual, surface brightness-dependent axis ratio uncertainties. For this
population we infer a mean intrinsic ellipticity E=0.43, and a mean triaxiality
T=0.16. This implies that faint Virgo galaxies are best described as a family
of thick, nearly oblate spheroids with mean intrinsic axis ratios 1:0.94:0.57.
We additionally attempt a study of the intrinsic shapes of Local Group
satellites of similar luminosities. For the LG population we infer a slightly
larger mean intrinsic ellipticity E=0.51, and the paucity of objects with round
apparent shapes translates into more triaxial mean shapes, 1:0.76:0.49. We
finally compare the intrinsic shapes of NGVS low-mass galaxies with samples of
more massive quiescent systems, and with field, star-forming galaxies of
similar luminosities. We find that the intrinsic flattening in this
low-luminosity regime is almost independent of the environment in which the
galaxy resides--but there is a hint that objects may be slightly rounder in
denser environments. The comparable flattening distributions of low-luminosity
galaxies that have experienced very different degrees of environmental effects
suggests that internal processes are the main drivers of galaxy structure at
low masses--with external mechanisms playing a secondary role.Comment: Accepted to ApJ. 18 pages, 12 figure
Recovering 3D structural properties of galaxies from SDSS-like photometry
Because of the 3D nature of galaxies, an algorithm for constructing spatial
density distribution models of galaxies on the basis of galaxy images has many
advantages over surface density distribution approximations. We present a
method for deriving spatial structure and overall parameters of galaxies from
images and estimate its accuracy and derived parameter degeneracies on a sample
of idealised model galaxies. The test galaxies consist of a disc-like component
and a spheroidal component with varying proportions and properties. Both
components are assumed to be axially symmetric and coplanar. We simulate these
test galaxies as if observed in the SDSS project through ugriz filters, thus
gaining a set of realistically imperfect images of galaxies with known
intrinsic properties. These artificial SDSS galaxies were thereafter remodelled
by approximating the surface brightness distribution with a 2D projection of a
bulge+disc spatial distribution model and the restored parameters were compared
to the initial ones. Down to the r-band limiting magnitude 18, errors of the
restored integral luminosities and colour indices remain within 0.05 mag and
errors of the luminosities of individual components within 0.2 mag. Accuracy of
the restored bulge-to-disc ratios (B/D) is within 40% in most cases, and
becomes worse for galaxies with low B/D, but the general balance between bulges
and discs is not shifted systematically. Assuming that the intrinsic disc axial
ratio is < 0.3, the inclination angles can be estimated with errors < 5deg for
most of the galaxies with B/D < 2 and with errors < 15deg up to B/D = 6. Errors
of the recovered sizes of the galactic components are below 10% in most cases.
In general, models of disc components are more accurate than models of
spheroidal components for geometrical reasons.Comment: 15 pages, 13 figures, accepted for publication in RA
A Bayesian approach to strong lensing modelling of galaxy clusters
In this paper, we describe a procedure for modelling strong lensing galaxy
clusters with parametric methods, and to rank models quantitatively using the
Bayesian evidence. We use a publicly available Markov chain Monte-Carlo (MCMC)
sampler ('Bayesys'), allowing us to avoid local minima in the likelihood
functions. To illustrate the power of the MCMC technique, we simulate three
clusters of galaxies, each composed of a cluster-scale halo and a set of
perturbing galaxy-scale subhalos. We ray-trace three light beams through each
model to produce a catalogue of multiple images, and then use the MCMC sampler
to recover the model parameters in the three different lensing configurations.
We find that, for typical Hubble Space Telescope (HST)-quality imaging data,
the total mass in the Einstein radius is recovered with ~1-5% error according
to the considered lensing configuration. However, we find that the mass of the
galaxies is strongly degenerated with the cluster mass when no multiple images
appear in the cluster centre. The mass of the galaxies is generally recovered
with a 20% error, largely due to the poorly constrained cut-off radius.
Finally, we describe how to rank models quantitatively using the Bayesian
evidence. We confirm the ability of strong lensing to constrain the mass
profile in the central region of galaxy clusters in this way. Ultimately, such
a method applied to strong lensing clusters with a very large number of
multiple images may provide unique geometrical constraints on cosmology. The
implementation of the MCMC sampler used in this paper has been done within the
framework of the Lenstool software package, which is publicly available.Comment: Accepted to "Gravitational Lensing" Focus Issue of the New Journal of
Physics (invited), 35 pages, 11 figures at reduced resolutio
Magnetic field structures of galaxies derived from analysis of Faraday rotation measures, and perspectives for the SKA
The forthcoming new-generation radio telescope SKA (Square Kilometre Array)
and its precursors will provide a rapidly growing number of polarized radio
sources. Our analysis aims on what can be learned from these sources concerning
the structure and evolution of magnetic fields of external galaxies.
Recognition of magnetic structures is possible from Faraday rotation measures
() towards background sources behind galaxies. We construct models
for the ionized gas and magnetic field patterns of different azimuthal symmetry
(axisymmetric, bisymmetric and quadrisymmetric spiral, and superpositions) plus
a halo magnetic field. \RM fluctuations with a Kolmogorov spectrum due to
turbulent fields and/or fluctuations in ionized gas density are superimposed.
Assuming extrapolated number density counts of polarized sources, we generate a
sample of \RM values within the solid angle of the galaxy. Applying various
templates, we derive the minimum number of background sources and the minimum
quality of the observations. For a large number of sources, reconstruction of
the field structure without precognition becomes possible. Any large-scale
regular component of the magnetic field can be clearly recognized from \RM
data with help of the criterium. Under favourite conditions, about a
few dozens of polarized sources are sufficient for a reliable result.Comment: 16 pages, 18 figures, accepted for publication in A&
The Morphological Content of Ten EDisCS Clusters at 0.5 < z < 0.8
We describe Hubble Space Telescope (HST) imaging of 10 of the 20 ESO Distant
Cluster Survey (EDisCS) fields. Each ~40 square arcminute field was imaged in
the F814W filter with the Advanced Camera for Surveys Wide Field Camera. Based
on these data, we present visual morphological classifications for the ~920
sources per field that are brighter than I_auto=23 mag. We use these
classifications to quantify the morphological content of 10
intermediate-redshift (0.5 < z < 0.8) galaxy clusters within the HST survey
region. The EDisCS results, combined with previously published data from seven
higher redshift clusters, show no statistically significant evidence for
evolution in the mean fractions of elliptical, S0, and late-type (Sp+Irr)
galaxies in clusters over the redshift range 0.5 < z < 1.2. In contrast,
existing studies of lower redshift clusters have revealed a factor of ~2
increase in the typical S0 fraction between z=0.4 and z=0, accompanied by a
commensurate decrease in the Sp+Irr fraction and no evolution in the elliptical
fraction. The EDisCS clusters demonstrate that cluster morphological fractions
plateau beyond z ~ 0.4. They also exhibit a mild correlation between
morphological content and cluster velocity dispersion, highlighting the
importance of careful sample selection in evaluating evolution. We discuss
these findings in the context of a recently proposed scenario in which the
fractions of passive (E,S0) and star-forming (Sp,Irr) galaxies are determined
primarily by the growth history of clusters.Comment: 18 pages, 7 figures; To be published in ApJ; minor changes made to
table label
Geometrical tests of cosmological models. III. The cosmology-evolution diagram at z=1
The rotational velocity of distant galaxies, when interpreted as a size
(luminosity) indicator, may be used as a tool to select high redshift standard
rods (candles) and probe world models and galaxy evolution via the classical
angular diameter-redshift or Hubble diagram tests. We implement the proposed
testing strategy using a sample of 30 rotators spanning the redshift range
0.2<z<1 with high resolution spectra and images obtained by the VIMOS/VLT Deep
Redshift Survey (VVDS) and the Great Observatories Origins Deep Survey (GOODs).
We show that by applying at the same time the angular diameter-redshift and
Hubble diagrams to the same sample of objects (i.e. velocity selected galactic
discs) one can derive a characteristic chart, the cosmology-evolution diagram,
mapping the relation between global cosmological parameters and local
structural parameters of discs such as size and luminosity. This chart allows
to put constraints on cosmological parameters when general prior information
about discs evolution is available. In particular, by assuming that equally
rotating large discs cannot be less luminous at z=1 than at present (M(z=1) <
M(0)), we find that a flat matter dominated cosmology (Omega_m=1) is excluded
at a confidence level of 2sigma and an open cosmology with low mass density
(Omega_m = 0.3) and no dark energy contribution is excluded at a confidence
level greater than 1 sigma. Inversely, by assuming prior knowledge about the
cosmological model, the cosmology-evolution diagram can be used to gain useful
insights about the redshift evolution of the structural parameters of baryonic
discs hosted in dark matter halos of nearly equal masses.Comment: 14 pages and 11 figures. A&A in pres
3C459: A highly asymmetric radio galaxy with a starburst
Multifrequency radio observations of the radio galaxy 3C459 using MERLIN, VLA
and the EVN, and an optical HST image using the F702W filter are presented. The
galaxy has a very asymmetric radio structure, a high infrared luminosity and a
young stellar population. The eastern component of the double-lobed structure
is brighter, much closer to the nucleus and is significantly less polarized
than the western one. This is consistent with the jet on the eastern side
interacting with dense gas, which could be due to a merged companion or dense
cloud of gas. The HST image of the galaxy presented here exhibits filamentary
structures, and is compared with the MERLIN 5-GHz radio map. EVN observations
of the prominent central component, which has a steep radio spectrum, show a
strongly curved structure suggesing a bent or helical radio jet. The radio
structure of 3C459 is compared with other highly asymmetric, Fanaroff-Riley II
radio sources, which are also good candidates for studying jet-cloud
interactions. Such sources are usually of small linear size and it is possible
that the jets are interacting with clouds of infalling gas that fuel the radio
source.Comment: 10 pages, 6 figures, 2 table
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