74 research outputs found
Economic and Environmental Evaluation of a Single-Story Steel Building in Its Life Cycle: A Comprehensive Analysis
In this study, the possibility of applying the Life Cycle Thinking approach to structural design, considering all aspects and phases of the structure's life, is investigated. The idea is to develop a procedure for the analysis of the economic and environmental impacts of structures in their life cycle, including not only ordinary costs along life cycle phases but also the extraordinary costs resulting from damage and anticipated end-of-life caused by unexpected natural hazards. The building performance under extraordinary conditions is calculated according to a time-based Loss Assessment Analysis. Such analysis provides the probable performance of a building and its components over a given period of time, considering all the hazardous events that can occur in that period, the probability of occurrence of each event, and the related effects. The outlined approach is applied to a case study of a single-story steel office building located in Italy. Two LC scenarios, having a duration of 2 years and 50 years, are considered. Results show that contributions of environmental impacts and benefits related to end-of-life management and economic losses for natural hazards are significant and not negligible. It is highlighted that the greatest challenge faced when using such a comprehensive approach is represented by data availability and representativeness that deeply limits the possibility of its implementation
Global and Regional IUCN Red List Assessments: 1
In this contribution, the conservation status assessment of six plant species according to IUCN categories and criteria are presented. It includes the assessment at global level of Linaria tonzigii Lona, Allium garganicum Brullo, Pavone, Salmeri & Terrasi, Ferula arrigonii Bocchieri, Orchis patens Desf. subsp. patens and Armeria saviana Selvi and the assessment at regional level (Italy) of Viola jordanii Hanry
Joint Observation of the Galactic Center with MAGIC and CTA-LST-1
MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes (IACTs), designed to detect very-high-energy gamma rays, and is operating in stereoscopic mode since 2009 at the Observatorio del Roque de Los Muchachos in La Palma, Spain. In 2018, the prototype IACT of the Large-Sized Telescope (LST-1) for the Cherenkov Telescope Array, a next-generation ground-based gamma-ray observatory, was inaugurated at the same site, at a distance of approximately 100 meters from the MAGIC telescopes. Using joint observations between MAGIC and LST-1, we developed a dedicated analysis pipeline and established the threefold telescope system via software, achieving the highest sensitivity in the northern hemisphere. Based on this enhanced performance, MAGIC and LST-1 have been jointly and regularly observing the Galactic Center, a region of paramount importance and complexity for IACTs. In particular, the gamma-ray emission from the dynamical center of the Milky Way is under debate. Although previous measurements suggested that a supermassive black hole Sagittarius A* plays a primary role, its radiation mechanism remains unclear, mainly due to limited angular resolution and sensitivity. The enhanced sensitivity in our novel approach is thus expected to provide new insights into the question. We here present the current status of the data analysis for the Galactic Center joint MAGIC and LST-1 observations
Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)
Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters.
Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs).
Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001).
Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio
MAGIC and H.E.S.S. detect VHE gamma rays from the blazar OT081 for the first time: a deep multiwavelength study
https://pos.sissa.it/395/815/pdfPublished versio
The UHECR-FR0 Radio Galaxy Connection: A Multi-Messenger Study of Energy Spectra/Composition Emission and Intergalactic Magnetic Field Propagation
This study investigates low luminosity Fanaroff-Riley Type 0 (FR0) radio galaxies as a potentially
significant source of ultra-high energy cosmic rays (UHECRs). Due to their much higher prevalence
in the local universe compared to more powerful radio galaxies (about five times more than
FR-1s), FR0s may provide a substantial fraction of the total UHECR energy density. To determine
the nucleon composition and energy spectrum of UHECRs emitted by FR0 sources, simulation
results from CRPropa3 are fit to Pierre Auger Observatory data. The resulting emission spectral
indices, rigidity cutoffs, and nucleon fractions are compared to recent Auger results. The FR0 simulations
include the approximately isotropic distribution of FR0 galaxies and various intergalactic
magnetic field configurations (including random and structured fields) and predict the fluxes of
secondary photons and neutrinos produced during UHECR propagation through cosmic photon
backgrounds. This comprehensive simulation allows for investigating the properties of the FR0
sources using observational multi-messenger data
Scrutinizing FR 0 Radio Galaxies as Ultra-High-Energy Cosmic Ray Source Candidates
Fanaroff-Riley (FR) 0 radio galaxies compose a new class of radio galaxies,
which are usually weaker but much more numerous than the well-established class
of FR 1 and FR 2 galaxies. The latter classes have been proposed as sources of
the ultra-high-energy cosmic rays (UHECRs) with energies reaching up to
eV. Based on this conjecture, the possibility of UHECR
acceleration and survival in an FR 0 source environment is examined in this
work.
In doing so, an average spectral energy distribution (SED) based on data from
the FR 0 catalog (FR0CAT) is compiled. The resulting photon fields are used as
targets for UHECRs, which suffer from electromagnetic pair production,
photo-disintegration, photo-meson production losses, and synchrotron radiation.
Multiple mechanisms are discussed to assess the UHECR acceleration probability,
including Fermi-I order and gradual shear accelerations, and particle escape
from the source region.
This work shows that in a hybrid scenario, combining Fermi and shear
accelerations, FR 0 galaxies can contribute to the observed UHECR flux, as long
as , where shear acceleration starts to dominate
over escape. Even in less optimistic scenarios, FR 0s can be expected to
contribute to the cosmic-ray flux between the knee and the ankle. Our results
are relatively robust with respect to the realized magnetic turbulence model
and the speed of the accelerating shocks.Comment: 19 pages, 16 figures, 4 tables, accepted in Astroparticle Physic
Extrapolating FR-0 radio galaxy source properties from propagation of multi-messenger ultra-high energy cosmic rays
Recently, it has been shown that relatively low luminosity Fanaroff-Riley type 0 (FR-0) radio galaxies are a good candidate source class for a predominant fraction of cosmic rays (CR) accelerated to ultra-high energies (UHE, E>10[sup]18 eV). FR-0s can potentially provide a significant fraction
of the UHECR energy density as they are much more numerous in the local universe than more energetic radio galaxies such as FR-1s or FR-2s (up to a factor of ∼5 with z≤0.05 compared to
FR-1s).
In the present work, UHECR mass composition and energy spectra at the FR-0 sources are estimated by fitting simulation results to the published Pierre Auger Observatory data. This fitting is done using a simulated isotropic sky distribution extrapolated from the measured FR-0 galaxy properties and propagating CRs in plausible extragalactic magnetic field configurations using the CRPropa3 framework. In addition, we present estimates of the fluxes of secondary photons and neutrinos created in UHECR interactions with cosmic photon backgrounds during
CR propagation. With this approach, we aim to investigate the properties of the sources with the help of observational multi-messenger data
Scrutinizing FR 0 radio galaxies as ultra-high-energy cosmic ray source candidates
Fanaroff-Riley (FR) 0 radio galaxies compose a new class of radio galaxies, which are usually weaker but much more numerous than the well-established class of FR 1 and FR 2 galaxies. The latter classes have been proposed as sources of the ultra-high-energy cosmic rays (UHECRs) with energies reaching up to eV. Based on this conjecture, the possibility of UHECR acceleration and survival in an FR 0 source environment is examined in this work.
In doing so, an average spectral energy distribution (SED) based on data from the FR 0 catalog (FR0CAT) is compiled. The resulting photon fields are used as targets for UHECRs, which suffer from electromagnetic pair production, photo-disintegration, photo-meson production losses, and synchrotron radiation. Multiple mechanisms are discussed to assess the UHECR acceleration probability, including Fermi-I order and gradual shear accelerations, and particle escape from the source region.
This work shows that in a hybrid scenario, combining Fermi and shear accelerations, FR 0 galaxies can contribute to the observed UHECR flux, as long as where shear acceleration starts to dominate over escape. Even in less optimistic scenarios, FR 0s can be expected to contribute to the cosmic-ray flux between the knee and the ankle. Our results are relatively robust with respect to the realized magnetic turbulence model and the speed of the accelerating shocks
FR-0 jetted active galaxies
Fanaroff-Riley (FR) 0 radio galaxies form a low-luminosity extension to the well-established ultra-high-energy cosmic-ray (UHECR) candidate accelerators FR-1 and FR-2 galaxies. Their much higher number density — up to a factor five times more numerous than FR-1 with z ≤ 0.05 — makes them good candidate sources for an isotropic contribution to the observed UHECR flux.
Here, the acceleration and survival of UHECR in prevailing conditions of the FR-0 environment are discussed.
First, an average spectral energy distribution (SED) is compiled based on the FR0CAT. These photon fields, composed of a jet and a host galaxy component, form a minimal target photon field for the UHECR, which will suffer from electromagnetic pair production, photo-disintegration, photo-meson production losses, and synchrotron radiation. The two most promising acceleration scenarios based on Fermi-I order and gradual shear acceleration are discussed as well as different
escape scenarios.
When an efficient acceleration mechanism precedes gradual shear acceleration, e.g., Fermi-I orothers, FR-0 galaxies are likely UHECR accelerators. Gradual shear acceleration requires a jet
Lorentz factor of Gamma>1.6, to be faster than the corresponding escape. In less optimistic models, a contribution to the cosmic-ray flux between the knee and ankle is expected to be relatively independent of the realized turbulence and acceleration
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