132 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
Quantifying Spectral Features of Type Ia Supernovae
We introduce a new technique to quantify highly structured spectra for which
the definition of continua or spectral features in the observed flux spectra is
difficult. The method employs wavelet transformation which allows the
decomposition of the observed spectra into different scales. A procedure is
formulated to define the strength of spectral features so that the measured
spectral indices are independent of the flux levels and are insensitive to the
definition of continuum and also to reddening. This technique is applied to
Type Ia supernovae spectra, where correlations are revealed between the
luminosity and spectral features. The current technique may allow for
luminosity corrections based on spectral features in the use of Type Ia
supernovae as cosmological probe.Comment: 35 pages, 15 figure
Diversity of supernovae Ia determined using equivalent widths of Si II 4000
Spectroscopic and photometric properties of low and high-z supernovae Ia (SNe
Ia) have been analyzed in order to achieve a better understanding of their
diversity and to identify possible SN Ia sub-types. We use wavelet transformed
spectra in which one can easily measure spectral features. We investigate the
\ion{Si}{II} 4000 equivalent width (EW_w\lbrace\ion{Si}{II}\rbrace). The
ability and, especially, the ease in extending the method to SNe at high- is
demonstrated. We applied the method to 110 SNe Ia and found correlations
between EW_w\lbrace\ion{Si}{II}\rbrace and parameters related to the
light-curve shape for 88 supernovae with available photometry. No evidence for
evolution of EW_w\lbrace\ion{Si}{II}\rbrace with redshift is seen. Three
sub-classes of SNe Ia were confirmed using an independent cluster analysis with
only light-curve shape, colour, and EW_w\lbrace\ion{Si}{II}\rbrace. SNe from
high- samples seem to follow a similar grouping to nearby objects. The
EW_w\lbrace\ion{Si}{II}\rbrace value measured on a single spectrum may point
towards SN Ia sub-classification, avoiding the need for expansion velocity
gradient calculations.Comment: 12 pages, 5 figure
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
High-Velocity Features: a ubiquitous property of Type Ia SNe
Evidence of high-velocity features such as those seen in the near-maximum
spectra of some Type Ia Supernovae (eg SN 2000cx) has been searched for in the
available SNIa spectra observed earlier than one week before B maximum. Recent
observational efforts have doubled the number of SNeIa with very early spectra.
Remarkably, all SNeIa with early data (7 in our RTN sample and 10 from other
programmes) show signs of such features, to a greater or lesser degree, in CaII
IR, and some also in SiII 6255A line. High-velocity features may be interpreted
as abundance or density enhancements. Abundance enhancements would imply an
outer region dominated by Si and Ca. Density enhancements may result from the
sweeping up of circumstellar material by the highest velocity SN ejecta. In
this scenario, the high incidence of HVFs suggests that a thick disc and/or a
high-density companion wind surrounds the exploding white dwarf, as may be the
case in Single Degenerate systems. Large-scale angular fluctuations in the
radial density and abundance distribution may also be responsible: this could
originate in the explosion, and would suggest a deflagration as the more likely
explosion mechanism. CSM-interaction and surface fluctuations may coexist,
possibly leaving different signatures on the spectrum. In some SNe the HVFs are
narrowly confined in velocity, suggesting the ejection of blobs of burned
material.Comment: 12 pages, 2 figures, ApJ Letters in pres
The Spectroscopic Diversity of Type Ia Supernovae
We present 2603 spectra of 462 nearby Type Ia supernovae (SN Ia) obtained
during 1993-2008 through the Center for Astrophysics Supernova Program. Most of
the spectra were obtained with the FAST spectrograph at the FLWO 1.5m telescope
and reduced in a consistent manner, making data set well suited for studies of
SN Ia spectroscopic diversity. We study the spectroscopic and photometric
properties of SN Ia as a function of spectroscopic class using the
classification schemes of Branch et al. and Wang et al. The width-luminosity
relation appears to be steeper for SN Ia with broader lines. Based on the
evolution of the characteristic Si II 6355 line, we propose improved methods
for measuring velocity gradients, revealing a larger range than previously
suspected, from ~0 to ~400 km/s/day considering the instantaneous velocity
decline rate at maximum light. We find a weaker and less significant
correlation between Si II velocity and intrinsic B-V color at maximum light
than reported by Foley et al., owing to a more comprehensive treatment of
uncertainties and host galaxy dust. We study the extent of nuclear burning and
report new detections of C II 6580 in 23 early-time spectra. The frequency of C
II detections is not higher in SN Ia with bluer colors or narrower light
curves, in conflict with the recent results of Thomas et al. Based on nebular
spectra of 27 SN Ia, we find no relation between the FWHM of the iron emission
feature at ~4700 A and Dm15(B) after removing the two low-luminosity SN 1986G
and SN 1991bg, suggesting that the peak luminosity is not strongly dependent on
the kinetic energy of the explosion for most SN Ia. Finally, we confirm the
correlation of velocity shifts in some nebular lines with the intrinsic B-V
color of SN Ia at maximum light, although several outliers suggest a possible
non-monotonic behavior for the largest blueshifts.Comment: 36 pages (emulateapj), 23 figures. Accepted for publication in AJ.
Spectroscopic data available at
http://www.cfa.harvard.edu/supernova/SNarchive.html . New SNID template set
available at http://marwww.in2p3.fr/~blondin/software/snid/index.html . Minor
changes from v1 to conform to published versio
ESC observations of SN 2005cf: II. Optical Spectroscopy and the high velocity features
The ESC-RTN optical spectroscopy data-set for SN 2005cf is presented and
analyzed. The observations range from -11.6 and +77.3 days with respect to
B-band maximum light. The evolution of the spectral energy distribution of SN
2005cf is characterized by the presence of high velocity SiII and CaII
features. SYNOW synthetic spectra are used to investigate the ejecta geometry
of silicon. Based on the synthetic spectra the SiII high velocity feature
appears detached at 19500 km/s. We also securely establish the presence of such
feature in SN 1990N, SN 1994D, SN 2002er and SN 2003du. On a morphological
study both the CaII IR Triplet and H&K absorption lines of SN 2005cf show high
velocity features centered around 24000 km/s. When compared with other Type Ia
SNe based on the scheme presented in Benetti et al. 2005 SN 2005cf definitely
belongs to the LVG group.Comment: A&A accepted for publicatio
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&
SALT: a Spectral Adaptive Light curve Template for Type Ia Supernovae
We present a new method to parameterize Type Ia Supernovae (SN Ia)
multi-color light curves. The method was developed in order to analyze the
large number of SN Ia multi-color light curves measured in current
high-redshift projects. The technique is based on empirically modeling SN Ia
luminosity variations as a function of phase, wavelength, a shape parameter,
and a color parameter. The model is trained with a sample of well measured
nearby SN Ia and then tested with an independent set of supernovae by building
an optimal luminosity distance estimator combining the supernova rest-frame
luminosity, shape parameter and color reconstructed with the model. The
distances we measure using B- and V-band data show a dispersion around the
Hubble line comparable or lower than obtained with other methods. With this
model, we are able to measure distances using U- and B-band data with a
dispersion around the Hubble line of 0.16 +- 0.05.Comment: Accepted in A&A, June 23, 2005 (printer friendly replacement version,
includes language corrections
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