42 research outputs found
Spectro-Imaging Forward Model of Red and Blue Galaxies
For the next generation of spectroscopic galaxy surveys, it is important to
forecast their performances and to accurately interpret their large data sets.
For this purpose, it is necessary to consistently simulate different
populations of galaxies, in particular Emission Line Galaxies (ELGs), less used
in the past for cosmological purposes. In this work, we further the forward
modeling approach presented in Fagioli et al. 2018, by extending the spectra
simulator Uspec to model galaxies of different kinds with improved parameters
from Tortorelli et al. 2020. Furthermore, we improve the modeling of the
selection function by using the image simulator Ufig. We apply this to the
Sloan Digital Sky Survey (SDSS), and simulate multi-band images.
We pre-process and analyse them to apply cuts for target selection, and finally
simulate SDSS/BOSS DR14 galaxy spectra. We compute photometric, astrometric and
spectroscopic properties for red and blue, real and simulated galaxies, finding
very good agreement. We compare the statistical properties of the samples by
decomposing them with Principal Component Analysis (PCA). We find very good
agreement for red galaxies and a good, but less pronounced one, for blue
galaxies, as expected given the known difficulty of simulating those. Finally,
we derive stellar population properties, mass-to-light ratios, ages and
metallicities, for all samples, finding again very good agreement. This shows
how this method can be used not only to forecast cosmology surveys, but it is
also able to provide insights into studies of galaxy formation and evolution.Comment: 28 pages, 10 figures, accepted for publication in JCA
Forward Modeling of Spectroscopic Galaxy Surveys: Application to SDSS
Galaxy spectra are essential to probe the spatial distribution of galaxies in
our Universe. To better interpret current and future spectroscopic galaxy
redshift surveys, it is important to be able to simulate these data sets. We
describe Uspec, a forward modeling tool to generate galaxy spectra taking into
account some intrinsic galaxy properties as well as instrumental responses of a
given telescope. The model for the intrinsic properties of the galaxy
population, i.e., the luminosity functions, and size and spectral coefficients
distribu- tions, was developed in an earlier work for broad-band imaging
surveys [1], and we now aim to test the model further using spectroscopic data.
We apply Uspec to the SDSS/CMASS sample of Luminous Red Galaxies (LRGs). We
construct selection cuts that match those used to build this LRG sample, which
we then apply to data and simulations in the same way. The resulting real and
simulated average spectra show a good statistical agreement overall, with
residual differences likely coming from a bluer galaxy population of the
simulated sam- ple. We also do not explore the impact of non-solar element
ratios in our simulations. For a quantitative comparison, we perform Principal
Component Analysis (PCA) of the sets of spectra. By comparing the PCs
constructed from simulations and data, we find good agree- ment for all
components. The distributions of the eigencoefficients also show an appreciable
overlap. We are therefore able to properly simulate the LRG sample taking into
account the SDSS/BOSS instrumental responses. The differences between the two
samples can be ascribed to the intrinsic properties of the simulated galaxy
population, which can be reduced by further improvements of our modelling
method in the future. We discuss how these results can be useful for the
forward modeling of upcoming large spectroscopic surveys.Comment: 32 pages, 14 figures, accepted by JCA
Uno studio sulle caratteristiche di un campione di pazienti internati presso l'Ospedale Psichiatrico Giudiziario di Castiglione delle Stiviere e dimessi nella regione Lazio.
Aim. The aim of this study was: i) To identify socio-demographic and clinical data in a sample of inmates in the Criminal Mental Hospital (CMH) at Castiglione delle Stiviere; ii) to assess the presence of characteristics which could foresee the commission of a crime of psychiatric interest; iii) to assess the frequency of crime repetition. Materials and Methods. This study was carried out on a sample of 38 patients. A descriptive analysis of the sample was carried out and the associations among several variables were analyzed. Results. The sample is characterized by a high frequency of schizophrenia diagnosis (73.0%), the presence of hospitalization before the commission of the crime (68.4%) and the absence of criminal precedents (71.1%). For men the age of the commission of the crime is equal to 33.72±10.6 years and for women to 45.18±11.4 years (p=0.011). The time between the onset and the commission of the crime is longer in patients who have received therapy (treatment) than in those ones with no treatment (p=0.012). About 12% of the sample committed new crimes. Conclusions. The results showed previous criminal acts are not predictive for the commission of new crimes of psychiatric interest. However many patients had previous contacts with community facilities before their first admission to hospital and the treatment extended the interval between the onset of the disease and the commission of the crime. The relapse rate after the discharge was very low if compared with samples coming from other services that offered more custodial rather than rehabilitative facilities
Dalla crisi del paradigma neokraepeliniano verso una nuova nosografia psichiatrica. Il DSM-5.
With this article we intend to outline the story of American psychiatry starting at the end of the 19th
century until the present time, describing the cultural, political and economic context which culminated
in the development and diffusion of biological psychiatry and its nosography.
The diffusion of psychoanalysis and of A. Meyerâs psychological psychiatry, beginning at the end of
the Second World War until the end of the Sixties, determined such as an enlargement of psychiatric
diagnosis which no longer allowed one to distinguish a sane individual from an ill individual. This
âdimensionalâ model caused a slow process of de-medicalization of psychiatry which removed consent
and legitimacy from the discipline. The answer was the publication in 1980 of DSM III, the work
of a small number of psychiatrists known as the âNeo-Kraepeliniansâ. The new nosography based on
a categorial diagnostic system, emphasized what is directly observable and therefore measurable,
and not what is clinically significant. Whit DSM III and the successive versions the interest of the psychiatrists
moved from the clinical to the epidemiological research. In the attempt to take psychiatry
back to one of the medical sciences DSM III has in reality continued the process of undermining started
whit Meyer and psychoanalysis. And now with the forthcoming publication of DSM V, psychiatry
will be confused ever more with neurosciences
Spectro-imaging forward model of red and blue galaxies
For the next generation of spectroscopic galaxy surveys, it is important to forecast their performances and to accurately interpret their large data sets. For this purpose, it is necessary to consistently simulate different populations of galaxies, in particular Emission Line Galaxies (ELGs), less used in the past for cosmological purposes. In this work, we further the forward modeling approach presented in Fagioli et al. 2018, by extending the spectra simulator USPEC to model galaxies of different kinds with improved parameters from Tortorelli et al. 2020. Furthermore, we improve the modeling of the selection function by using the image simulator UFIG. We apply this to the Sloan Digital Sky Survey (SDSS), and simulate similar to 157, 000 multi-band images. We pre-process and analyse them to apply cuts for target selection, and finally simulate SDSS/BOSS DR14 galaxy spectra. We compute photometric, astrometric and spectroscopic properties for red and blue, real and simulated galaxies, finding very good agreement. We compare the statistical properties of the samples by decomposing them with Principal Component Analysis (PCA). We find very good agreement for red galaxies and a good, but less pronounced one, for blue galaxies, as expected given the known difficulty of simulating those. Finally, we derive stellar population properties, mass-to-light ratios, ages and metallicities, for all samples, finding again very good agreement. This shows how this method can be used not only to forecast cosmology surveys, but it is also able to provide insights into studies of galaxy formation and evolution.ISSN:1475-751