13,310 research outputs found
Massive galaxies with very young AGN
Gigahertz Peaked Spectrum (GPS) radio galaxies are generally thought to be
the young counterparts of classical extended radio sources and live in massive
ellipticals. GPS sources are vital for studying the early evolution of
radio-loud AGN, the trigger of their nuclear activity, and the importance of
feedback in galaxy evolution. We study the Parkes half-Jansky sample of GPS
radio galaxies of which now all host galaxies have been identified and 80% has
their redshifts determined (0.122 < z < 1.539). Analysis of the absolute
magnitudes of the GPS host galaxies show that at z > 1 they are on average a
magnitude fainter than classical 3C radio galaxies. This suggests that the AGN
in young radio galaxies have not yet much influenced the overall properties of
the host galaxy. However their restframe UV luminosities indicate that there is
a low level of excess as compared to passive evolution models.Comment: To appear in the proceedings of "Formation and Evolution of Galaxy
Bulges", IAUS 245; M. Bureau, E. Athanassoula & B. Barbuy, ed
An implicit pictorial methodology for measuring and retraining smokers' reactivity to pictures of pros and cons of smoking:development protocol
AbstractObjectivesThe last decades, there has been increased interest in the application of implicit pictorial tasks (e.g. Visual Probe Task (VPT), Approach Avoidance Task (AAT)) to target addictive behaviors. The present study reports on the development of implicit pictorial assessment and modification tasks aimed at targeting cognitive biases underlying motivational smoking-related cognitions (i.e. the pros and cons of smoking).MethodsRespondents were adult daily smokers not motivated to quit smoking within six months (NÂ =Â 33). A cross-sectional four-step approach using qualitative and quantitative strategies was utilized to identify and match pictures of pros and cons of smoking.ResultsThe study resulted in 30 pro-con picture pairs matched on valence, arousal and complexity: the picture pairs were used to develop a VPT assessment and training for attentional biases and an AAT assessment and training for approach-avoidance biases.ConclusionsThe developed measurement and training tasks will be used to explore and change cognitive biases regarding pros and cons of smoking. This may consequently influence the perceived pros and cons of smoking and yield positive effects with regard to the motivation to quit smoking
GPS radio sources: new optical observations and an updated master list
* Aims. Identify optical counterparts, address uncertain identifications and
measure previously unknown redshifts of the host galaxies of candidate GPS
radio sources, and study their stellar populations. * Methods. Long slit
spectroscopy and deep optical imaging in the B, V and R bands, obtained with
the Very Large Telescope. * Results. We obtain new redshifts for B0316+161,
B0407-658, B0904+039, B1433-040, and identify the optical counterparts of
B0008-421 and B0742+103. We confirm the previous identification for B0316+161,
B0407-658, B0554-026, and B0904+039, and find that the previous identification
for B0914+114 is incorrect. Using updated published radio spectral information
we classify as non GPS the following sources: B0407-658, B0437-454, B1648+015.
The optical colors of typical GPS sources are consistent with single
instantaneous burst stellar population models but do not yield useful
information on age or metallicity. A new master list of GPS sources is
presented.Comment: 10 pages + GPS master list. Accepeted for publication by A&
The Astrophysical Multipurpose Software Environment
We present the open source Astrophysical Multi-purpose Software Environment
(AMUSE, www.amusecode.org), a component library for performing astrophysical
simulations involving different physical domains and scales. It couples
existing codes within a Python framework based on a communication layer using
MPI. The interfaces are standardized for each domain and their implementation
based on MPI guarantees that the whole framework is well-suited for distributed
computation. It includes facilities for unit handling and data storage.
Currently it includes codes for gravitational dynamics, stellar evolution,
hydrodynamics and radiative transfer. Within each domain the interfaces to the
codes are as similar as possible. We describe the design and implementation of
AMUSE, as well as the main components and community codes currently supported
and we discuss the code interactions facilitated by the framework.
Additionally, we demonstrate how AMUSE can be used to resolve complex
astrophysical problems by presenting example applications.Comment: 23 pages, 25 figures, accepted for A&
Examining the Geography of Illicit Massage Businesses Hosting Commercial Sex and Sex Trafficking in the United States: The Role of Census Tract and City-Level Factors
Despite extensive theory and research on the geography of crime, few studies have examined the geography of commercial sex and sex trafficking through a criminological lens. As such, this study explores how social disorganization and routine activities help explain the geography of commercial sex venues, specifically illicit massage businesses (IMBs) that host commercial sex. Because IMBs have also been linked to sex trafficking, understanding which environmental contexts are conducive to their presence may also help identify sex trafficking premises. Findings from hierarchical logistic regression models indicate that both theories point to significant correlates of IMB placement in census tracts and cities, yet neither theory provides a sufficient explanation alone. Implications for future research and policy will be discussed.U.S. National Institute of Justice 2018-R2-CX-0005Criminal Justice: Legitimacy, accountability, and effectivit
A Network Approach to Examine Neighborhood Interdependence Through the Target Selection of Repeat Buyers of Commercial Sex in the United States
The geographic concentration and diffusion of crime and deviancy are longstanding criminological inquiries, yet few studies have examined how certain illicit behaviors transcend neighborhood borders and connect neighborhoods in patterns of crime and deviancy. A structural neighborhood interdependence may account for the enduring nature and spread of crime, making it critical to understand how neighborhoods are connected in crime patterns to guide crime prevention and disruption efforts. This study examines neighborhood interdependence through the case of repeat buyers of commercial sex in illicit massage businesses in a metropolitan city in the United States. By frequenting venues for illicit commercial sex in multiple neighborhoods, buyers create inter-neighborhood connections through which the demand for an illicit market can spread across neighborhoods. Using online review data about buyers of commercial sex, this study analyzes this neighborhood interdependence as a network comprised of nodes (“neighborhoods”) and edges (“connections between neighborhoods”). Exponential random graph models were used to analyze how characteristics of neighborhoods, the space between neighborhoods, and the overall network of neighborhoods explain inter-neighborhood connectivity in an illicit market for commercial sex. The implications for research, policy, and practice will be discussed.U.S. National Institute of Justice 2018-R2-CX-0005Criminal Justice: Legitimacy, accountability, and effectivit
Nuclear medium effects in -nucleus deep inelastic scattering
We study the nuclear medium effects in the weak structure functions
and in the deep inelastic neutrino/antineutrino
reactions in nuclei.
We use a theoretical model for the nuclear spectral functions which
incorporates the conventional nuclear effects, such as Fermi motion, binding
and nucleon correlations.
We also consider the pion and rho meson cloud contributions calculated from a
microscopic model for meson-nucleus self-energies. The calculations have been
performed using relativistic nuclear spectral functions which include nucleon
correlations. Our results are compared with the experimental data of NuTeV and
CDHSW.Comment: 24 pages, 14 figure
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