111 research outputs found
Social report framing: Evidence from a major Italian bank
This study aims to analyse the development of a social report in a major Italian bank from its formation in 2007 to 2012.The Italian banking sector plays an important role in the Italian economy.Several Italian frameworks for social reports have been published and used by Italian companies.However, an important framework for social reports in Italy is the GRI.The paper aims to answer the following research questions: 1) what international guidelines have been used by the Bank in its social reports, during the period considered? 2) What have been the structural changes in the social report over time? The aim of these questions is to analyse the structure of the
Bank’s six social reports.The paper relies on documentary analysis, applied to six social reports. It is based on G3 Guidelines and Performance Indicators (PIs).The paper finds that in the six-year period several changes in social reports are highlighted.We conclude that the Bank has engaged in a process of continuous improvement in the information content of the social report, including recently indicating that a PI is only partially disclosed if not in accordance with the guidelines
Factors associated with SARS-CoV-2 infection risk among healthcare workers of an italian university hospital
We report the results of a study on the cumulative incidence of SARS-CoV-2 infections in about 6000 workers of the University Hospital of Modena, Northern Italy, in the period March 2020–January 2021, and the relations with some individual and occupational factors. Overall, in healthcare workers (HCW) the cumulative incidence of COVID-19 during the period was 13.8%. Results confirm the role of overweight and obesity as significant risk factors for SARS-CoV-2 infection. Chronic respiratory diseases, including asthma, also proved to be significantly associated with the infection rate. Considering occupational factors, the COVID-19 risk was about threefold (OR: 2.7; 95% CI 1.7–4.5) greater in nurses and nurse aides than in non-HCW, and about double (OR: 1.9; 95% CI 1.2–3.2) in physicians. Interestingly, an association was also observed between infection risk and nightshifts at work (OR: 1.8; 95% CI 1.4–2.3), significantly related to the total number of shifts in the whole eleven-month period. Even if the vaccination campaign has now greatly modified the scenario of SARS-CoV-2 infections among HCW, the results of this study can be useful for further development of health and policy strategies to mitigate the occupational risk related to the new variants of coronavirus, and therefore the evolution of the pandemic
NTT and NOT spectroscopy of SDSS-II supernovae
Context. The SDSS-II Supernova Survey, conducted between 2005 and 2007, was
designed to detect a large number of Type Ia supernovae (SNe Ia) around z~0.2,
the redshift "gap" between low-z and high-z SN searches. The survey has
provided multi-band photometric lightcurves for variable targets, and SN
candidates were scheduled for spectroscopic observations, primarily to provide
SN classification and accurate redshifts. We present SN spectra obtained in
2006 and 2007 using the NTT and the NOT. Aims. We provide an atlas of SN
spectra in the range z =0.03-0.32 that complements the well-sampled lightcurves
from SDSS-II in the forthcoming three-year SDSS SN cosmology analysis. The
sample can, for example, be used for spectral studies of SNe Ia, which are
critical for understanding potential systematic effects when SNe are used to
determine cosmological distances. Methods. The spectra were reduced in a
uniform manner, and special care was taken in estimating the uncertainties for
the different processing steps. Host-galaxy light was subtracted when possible
and the SN type fitted using the SuperNova IDentification code (SNID). We also
present comparisons between spectral and photometric dating using SALT
lightcurve fits to the photometry from SDSS-II, as well as the global
distribution of our sample in terms of the lightcurve parameters: stretch and
colour. Results. We report new spectroscopic data from 141 SNe Ia, mainly
between -9 and +15 days from lightcurve maximum, including a few cases of
multi-epoch observations. This homogeneous, host-galaxy subtracted, SN Ia
spectroscopic sample is among the largest such data sets and unique in its
redshift interval. The sample includes two potential SN 1991T-like SNe (SN
2006on and SN 2007ni) and one potential SN 2002cx-like SN (SN 2007ie). In
addition, the new compilation includes spectra from 23 confirmed Type II and 8
Type Ib/c SNe.Comment: Accepted for publication in A&
PHotometry Assisted Spectral Extraction (PHASE) and identification of SNLS supernovae
Aim: We present new extraction and identification techniques for supernova
(SN) spectra developed within the Supernova Legacy Survey (SNLS) collaboration.
Method: The new spectral extraction method takes full advantage of
photometric information from the Canada-France-Hawai telescope (CFHT) discovery
and reference images by tracing the exact position of the supernova and the
host signals on the spectrogram. When present, the host spatial profile is
measured on deep multi-band reference images and is used to model the host
contribution to the full (supernova + host) signal. The supernova is modelled
as a Gaussian function of width equal to the seeing. A chi-square minimisation
provides the flux of each component in each pixel of the 2D spectrogram. For a
host-supernova separation greater than <~ 1 pixel, the two components are
recovered separately and we do not use a spectral template in contrast to more
standard analyses. This new procedure permits a clean extraction of the
supernova separately from the host in about 70% of the 3rd year ESO/VLT spectra
of the SNLS. A new supernova identification method is also proposed. It uses
the SALT2 spectrophotometric template to combine the photometric and spectral
data. A galaxy template is allowed for spectra for which a separate extraction
of the supernova and the host was not possible.
Result: These new techniques have been tested against more standard
extraction and identification procedures. They permit a secure type and
redshift determination in about 80% of cases. The present paper illustrates
their performances on a few sample spectra.Comment: 27 pages, 18 Figures, 1 Table. Accepted for publication in A&
Supernova Legacy Survey: Using Spectral Signatures To Improve Type Ia Supernovae As Distance Indicators
GMOS optical long-slit spectroscopy at the Gemini-North telescope was used to
classify targets from the Supernova Legacy Survey (SNLS) from July 2005 and May
2006 - May 2008. During this time, 95 objects were observed. Where possible the
objects' redshifts (z) were measured from narrow emission or absorption
features in the host galaxy spectrum, otherwise they were measured from the
broader supernova features. We present spectra of 68 confirmed or probable SNe
Ia from SNLS with redshifts in the range 0.17 \leq z \leq 1.02. In combination
with earlier SNLS Gemini and VLT spectra, we used these new observations to
measure pseudo-equivalent widths (EWs) of three spectral features - CaII H&K,
SiII and MgII - in 144 objects and compared them to the EWs of low-redshift SNe
Ia from a sample drawn from the literature. No signs of changes with z are seen
for the CaII H&K and MgII features. Systematically lower EW SiII is seen at
high redshift, but this can be explained by a change in demographics of the SNe
Ia population within a two-component model combined with an observed
correlation between EW SiII and photometric lightcurve stretch.Comment: 49 pages including 2 online-only appendices, accepted for publication
in MNRA
Spectra of High-Redshift Type Ia Supernovae and a Comparison with their Low-Redshift Counterparts
We present spectra for 14 high-redshift (0.17 < z < 0.83) supernovae, which
were discovered by the Supernova Cosmology Project as part of a campaign to
measure cosmological parameters. The spectra are used to determine the redshift
and classify the supernova type, essential information if the supernovae are to
be used for cosmological studies. Redshifts were derived either from the
spectrum of the host galaxy or from the spectrum of the supernova itself. We
present evidence that these supernovae are of Type Ia by matching to spectra of
nearby supernovae. We find that the dates of the spectra relative to maximum
light determined from this fitting process are consistent with the dates
determined from the photometric light curves, and moreover the spectral
time-sequence for SNe Type Ia at low and high redshift is indistinguishable. We
also show that the expansion velocities measured from blueshifted CaHK are
consistent with those measured for low-redshift Type Ia supernovae. From these
first-level quantitative comparisons we find no evidence for evolution in SNIa
properties between these low- and high-redshift samples. Thus even though our
samples may not be complete, we conclude that there is a population of SNe Ia
at high redshift whose spectral properties match those at low redshift.Comment: Accepted for publication in AJ. Also available at
http://supernova.lbl.gov
SALT2: using distant supernovae to improve the use of Type Ia supernovae as distance indicators
We present an empirical model of Type Ia supernovae spectro-photometric
evolution with time. The model is built using a large data set including
light-curves and spectra of both nearby and distant supernovae, the latter
being observed by the SNLS collaboration. We derive the average spectral
sequence of Type Ia supernovae and their main variability components including
a color variation law. The model allows us to measure distance moduli in the
spectral range 2500-8000 A with calculable uncertainties, including those
arising from variability of spectral features. Thanks to the use of
high-redshift SNe to model the rest-frame UV spectral energy distribution, we
are able to derive improved distance estimates for SNe Ia in the redshift range
0.8<z<1.1. The model can also be used to improve spectroscopic identification
algorithms, and derive photometric redshifts of distant Type Ia supernovae.Comment: Accepted for publication in A&A. Data and source code available at :
http://supernovae.in2p3.fr/~guy/salt
Restframe I-band Hubble diagram for type Ia supernovae up to redshift z ~0.5
We present a novel technique for fitting restframe I-band light curves on a
data set of 42 Type Ia supernovae (SNe Ia). Using the result of the fit, we
construct a Hubble diagram with 26 SNe from the subset at 0.01< z<0.1. Adding
two SNe at z~0.5 yields results consistent with a flat
Lambda-dominated``concordance universe''
()=(0.25,0.75). For one of these, SN 2000fr, new near
infrared data are presented. The high redshift supernova NIR data are also used
to test for systematic effects in the use of SNe Ia as distance estimators. A
flat, Lambda=0, universe where the faintness of supernovae at z~0.5 is due to
grey dust homogeneously distributed in the intergalactic medium is disfavoured
based on the high-z Hubble diagram using this small data-set. However, the
uncertainties are large and no firm conclusion may be drawn. We explore the
possibility of setting limits on intergalactic dust based on B-I and B-V colour
measurements, and conclude that about 20 well measured SNe are needed to give
statistically significant results. We also show that the high redshift
restframe I-band data points are better fit by light curve templates that show
a prominent second peak, suggesting that they are not intrinsically
underluminous.Comment: Accepted for publication in A&A (01/04/2005
SNLS Spectroscopy: Testing for Evolution in Type Ia Supernovae
Aims: We present a quantitative study of a new data set of high redshift Type
Ia supernovae spectra, observed at the Gemini telescopes during the first 34
months of the Supernova Legacy Survey. During this time 123 supernovae
candidates were observed, of which 87 have been identified as SNe Ia at a
median redshift of z=0.720. Spectra from the entire second year of the survey
and part of the third year (59 total SNe candidates with 46 confirmed SNe Ia)
are published here for the first time. The spectroscopic measurements made on
this data set are used determine if these distant SNe comprise a population
similar to those observed locally. Methods: Rest-frame equivalent width and
ejection velocity measurements are made on four spectroscopic features.
Corresponding measurements are presented for a set of 167 spectra from 24 low-z
SNe Ia from the literature. Results: We show that there exists a sample at high
redshift with properties similar to nearby SNe. No significant difference was
found between the distributions of measurements at low and high redsift for
three of the features. The fourth feature displays a possible difference that
should be investigated further. Correlations between Type Ia SNe properties and
host galaxy morphology were also found to be similar at low and high z, and
within each host galaxy class we see no evidence for redshift-evolution in SN
properties. A new correlation between SNe Ia peak magnitude and the equivalent
width of SiII absorption is presented. We demonstrate that this correlation
reduces the scatter in SNe Ia luminosity distances in a manner consistent with
the lightcurve shape-luminosity corrections that are used for Type Ia SNe
cosmology. Conclusions: We show that this new sample of SNLS SNe Ia has
spectroscopic properties similar to nearby objects. (Abridged)Comment: Accepted for publication in Astronomy and Astrophysic
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