7,087 research outputs found
Seismic Q estimates in Umbria-Marche (central Italy): hints for the retrieval of a new attenuation law for seismic risk
In the Umbria Marche (Central Italy) region an important earthquake sequence occurred in 1997,
characterized by nine earthquakes with magnitudes in the range between 5 and 6, that caused
important damages and causalities. In the present paper we separately estimate intrinsic- and
scattering- Q
−1
parameters, using the classical MLTWA approach in the assumption of a half space
model. The results clearly show that the attenuation parameters Qi
−1
and Qs
−1
are frequency
dependent. This estimate is compared with other attenuation studies carried out in the same area, and
with all the other MLTWA estimates obtained till now in other tectonic environments in the Earth.
The bias introduced by the half space assumption is investigated through numerical solutions of the
Energy Transport equation in the more realistic assumption of a heterogeneous crust overlying a
transparent mantle, with a Moho located at a depth ranging between 35 and 45 km below the surface.
The bias introduced by the half space assumption is significant only at high frequency. We finally
show how the attenuation estimates, calculated with different techniques, lead to different PGA decay
with distance relationships, using the well known and well proven Boore’s method. This last result
indicates that care must be used in selecting the correct estimate of the attenuation parameters for
seismic risk purposes. We also discuss the reason why MLTWA may be chosen among all the other
available techniques, due to its intrinsic stability, to obtain the right attenuation parameters
Inclusive University didactics and technological devices: a case study
This paper provides a review of projects related to new technologies used to favour the teaching-learning processes and the inclusive practices in the University context for students with disabilities and with Specific Learning Disorders. Authors present a review of strategies, trajectories and perspectives activated in the national and international scene, aiming to guarantee a significant pedagogical framework of reference. Furthermore, the paper focuses on a meaningful path activated at the University of Macerata, the project Inclusion 3.0, a relevant example of new technologies in support of teaching- learning processes and inclusion practices among all students
The first Long Period earthquake detected in the background seismicity at Mt. Vesuvius
The typical earthquakes occurring at Mt. Vesuvius are Volcano-Tectonic. On July 20, 2003, an unusual earthquake with low and narrow frequency content was detected. The seismograms presented an emergent onset and a nearly monochromatic spectrum at all stations of the Osservatorio Vesuviano(Istituto Nazionale di Geofisica e Vulcanologia) seismic network. The event was located at about 4 km b.s.l. close to the crater axis and an equivalent duration magnitude of 0.6 was estimated. The nature of this event was investigated by comparing its features with those of two typical
Volcano-Tectonic earthquakes occurred inside the same source volume. We compared the spectral content calculating the spectrograms and the coda patterns using the Hilbert Transform. A Seismic Moment Tensor inversion was performed on the low frequency earthquake. The focal mechanisms for the two Volcano-Tectonic earthquakes were estimated with a classical technique and resulted compatible with the stress field acting on the volcano. Taking into account the clear differences with the typical Volcano-Tectonic events as well as the peculiarities retrieved from our analyses (monochromatic, low frequency spectral content, and sustained coda) and also some geochemical observations, we classify the unusual low frequency seismic event detected at Mt. Vesuvius as Long Period earthquake and propose that its origin could be linked to a pressure drop in the deep hydrothermal system
Measurement of the water vapour vertical profile and of the Earth's outgoing far infrared flux
International audienceOur understanding of global warming depends on the accuracy with which the atmospheric components that modulate the Earth's radiation budget are known. Many uncertainties still exist on the radiative effect of water in the different spectral regions, among which the far infrared where few observations have been made. An assessment is shown of the atmospheric outgoing flux obtained from a balloon-borne platform with wideband spectrally resolved nadir measurements at the top-of-atmosphere over the full spectral range, including the far infrared, from 100 to 1400 cm?1, made by a Fourier transform spectrometer with uncooled detectors. From these measurements, we retrieve 15 pieces of information about water vapour and temperature profiles, and surface temperature, with a precision of 5% for the mean water vapour profile and a major improvement of the upper troposphere-lower stratosphere knowledge. The retrieved atmospheric state makes it possible to calculate the emitted radiance as a function of the zenith angle and to determine the outgoing radiation flux, proving that spectrally resolved observations can be used to derive accurate information on the integrated flux. While the retrieved temperature is in good agreement with ECMWF analysis, the retrieved water vapour profile differs significantly, and, depending on time and location, the derived flux differs in the far infrared (0?600 cm?1) from that derived from ECMWF by 2?3.5 W/m2±0.4 W/m2. The observed discrepancy is larger than current estimates of radiative forcing due to CO2 increases since pre-industrial time. The error with which the flux is determined is caused mainly by calibration uncertainties while detector noise has a negligible effect, proving that uncooled detectors are adequate for top of the atmosphere radiometry
Differences in telomere length between sporadic and familial cutaneous melanoma
BACKGROUND:
Several pieces of evidence indicate that a complex relationship exists between constitutional telomere length (TL) and the risk of cutaneous melanoma. Although the general perception is that longer telomeres increase melanoma risk, some studies do not support this association. We hypothesise that discordant data are due to the characteristics of the studied populations.
OBJECTIVES:
To evaluate the association of telomere length with familial and sporadic melanoma.
METHODS:
TL was measured by multiplex quantitative PCR in leukocytes from 310 melanoma patients according to familial/sporadic and single/multiple cancers and 216 age-matched controls.
RESULTS:
Patients with sporadic melanoma were found to have shorter telomeres as compared to those with familial melanoma. In addition, shorter telomeres, while tending to reduce the risk of familial melanoma regardless of single or multiple tumors, nearly trebled the risk of single sporadic melanoma.
CONCLUSIONS:
This is the first time that TL has been correlated to opposite effects on melanoma risk according to the presence or absence of familial predisposition. Individual susceptibility to melanoma should be taken into account when assessing the role of TL as a risk factor. This article is protected by copyright. All rights reserved
Special pedagogy in Innovative Ecosystems: a pilot project for museums accessibility
Cultural institutes and museums are crucial in fostering individual and collective identity through heritage. To achieve this, they need to actively engage with the social context in which they operate by catering to diverse social groups. Inclusion is a key aspect that museums should prioritize, aiming to address the complexities of society and ensure equal cultural opportunities for all (Vaz et al., 2020). Based on these considerations, the University of Macerata, with a vocation on humanistic knowledge, promotes highly multidisciplinary activities within the Ecosystem project (financed by PNRR), with the aims to develop and transfer innovation to make regional production systems more competitive, thus improving sustainability and quality of life (Schalock et al., 2002) in urban and rural areas, and living and working environments. In this direction, the University of Macerata is developing different actions intending to create sustainable solutions and educational programmes for fragility and inclusiveness. Specifically, in line with national and international frameworks (Mace 1985; ONU, 2006), the commitment of Special Pedagogy research group will be directed at creating accessible solutions and organizational models to support access to local cultural heritage. Specifically, the Special Pedagogy group focuses its aim of research on accessibility and sustainability of inclusive tourism for usability of museums, art galleries, ecc
Co-design of immersive virtual learning environments. A pilot study involving people with intellectual disability and SLDs
This paper describes a pilot study conducted at the University of Macerata, within the project Inclusion 3.0. It aims to explore the possibility of using high-fidelity prototyping in a virtual laboratory to support the co-creation of an immersive virtual learning environment with people with disability and Specific Learning Disorders (SLDs), from the earliest design stages. The paper presents the results of the co-design process and discusses its implications in defining design requirements to ensure the accessibility of immersive solutions for cultural heritage
Use of Bio-Epoxies and Their Effect on the Performance of Polymer Composites: A Critical Review
This study comprehensively examines recent developments in bio-epoxy resins and their applications in composites. Despite the reliability of traditional epoxy systems, the increasing demand for sustainability has driven researchers and industries to explore new bio-based alternatives. Additionally, natural fibers have the potential to serve as environmentally friendly substitutes for synthetic ones, contributing to the production of lightweight and biodegradable composites. Enhancing the mechanical properties of these bio-composites also involves improving the compatibility between the matrix and fibers. The use of bio-epoxy resins facilitates better adhesion of natural composite constituents, addressing sustainability and environmental concerns. The principles and methods proposed for both available commercial and especially non-commercial bio-epoxy solutions are investigated, with a focus on promising renewable sources like wood, food waste, and vegetable oils. Bio-epoxy systems with a minimum bio-content of 20% are analyzed from a thermomechanical perspective. This review also discusses the effect of incorporating synthetic and natural fibers into bio-epoxy resins both on their own and in hybrid form. A comparative analysis is conducted against traditional epoxy-based references, with the aim of emphasizing viable alternatives. The focus is on addressing their benefits and challenges in applications fields such as aviation and the automotive industry
New insights into Mt. Vesuvius hydrothermal system and its dynamic based on a critical review of seismic tomography and geochemical features
The seismic velocity and attenuation tomography images, calculated inverting
respectively P-wave travel times and amplitude spectra of local
VT quakes at Mt. Vesuvius have been reviewed and graphically represented
using a new software recently developed using Mathematica8TM.
The 3-D plots of the interpolated velocity and attenuation fields obtained
through this software evidence low-velocity volumes associated with high
attenuation anomalies in the depth range from about 1 km to 3 km below
the sea level. The heterogeneity in the distribution of the velocity and attenuation
values increases in the volume centred around the crater axis
and laterally extended about 4 km, where the geochemical interpretation
of the data from fumarole emissions reveals the presence of a hydrothermal
system with temperatures as high as 400-450°C roughly in the same
depth range (1.5 km to 4 km). The zone where the hydrothermal system
is space-confined possibly hosted the residual magma erupted by Mt. Vesuvius
during the recent eruptions, and is the site where most of the seismic
energy release has occurred since the last 1944 eruption
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