699 research outputs found
Energy Enhancement of Solid Recovered Fuel within Systems of Conventional Thermal Power Generation
Abstract The main objective of this article is to verify the feasibility, in terms of technical and economical issues, of a new refuse-derived fuel SRF (Solid Recovered Fuel) to be used as a new fuel in a thermal power station or in an incineration plants. By means of the innovative micronization technology it is possible to produce SRF suitable for the technical specifications of the plants which, taking into account appropriate modifications, could be reconverted and not decommissioned. The present energy supply scenario shows a partial contraction of the activities of power plant thermal generation despite an increase of the power demand and despite one of the highest energy cost in Europe. It is likely to surmise a gradual stall of such activities and finally the decommissioning due to the fact that plants will turn out to be not economically productive. On the other hand, it is now necessary to promote adequate policies for sustainable waste management. An opportunity in this sense is represented by the smart usage (made possible through innovative manufacturing processes) of the SRF as an energy source. The tests conducted on the innovative chemical-mechanical micronization technology showed an average energetic cost of 30 kWh/ton, and an average production cost of 15 €/ton for the 0.5 mm size. Combustion tests showed a good environmental and combustion performance. In this article, the refuse-derived fuel (which is governed according to the Decrees of the Ministry of Environment, Land and Sea) has been obtained through an innovative technology of chemical-mechanical micronization. We have also proceeded to verify the functional feasibility of the fuel production in order to feed incinerators and power plants in partial or total substitution of the conventional fuels (coal, fuel oil)
Characterization of the breccia deposits in downtown L’Aquila (Central Italy) through multichannel analysis of surface waves
On April 6th 2009 an Mw 6.3 earthquake hit the historical city of L’Aquila (Central Italy) causing about 300
causalities, more than 39000 homeless and strong damage in the city and in the surrounding villages. L’Aquila
downtown suffered Mercalli-Cancani-Sieberg (MCS; Sieberg 1930) intensity > VIII. Heavy damage and collapses
were concentrated in the unreinforced masonry buildings including historical churches.
Starting from June 2009, the Italian Civil Defense Department promoted a microzoning study of the epicentral
area, aimed at identifying, at a detailed scale, areas were local seismic amplification could occur due to the
characteristics of surface geology.
L’Aquila is founded on a terrace that slopes down moving in the southwest direction, and raises about 50 meters
above the Aterno river bed. The terrace is formed by alluvial Quaternary breccias consisting of limestone clasts in
a marly matrix. In the northern part of the city the terrace is in contact with outcropping limestone, while moving
toward south, breccias are over imposed to lacustrine sediments formed mainly of silty and sandy layers and minor
gravel beds. As found by boreholes, the thickness of the breccias formation ranges from tenths of meters at north
to just few meters at south. The uppermost weathered part of breccias outcrops at south and is indicated as “limi
rossi”. The presence of breccias and “limi rossi” in the northern and southern part of the city respectively, is well
identified by collected geotechnical data. Shear wave velocity (Vs) are quite high in the northern sector and can
reach values of about 1000 m/s, whereas in the southernmost part the Vs of “limi rossi” drops down to 300-400
m/s. The microzoning studies at L’Aquila evidenced the presence of low-frequency (about 0.6 Hz) amplification
diffused in the historical center with high amplification factors in the southern area of the city were “limi rossi”
outcrops.
We here present the results of multichannel surface waves analysis (MASW) based on active and passive sources.
Active methods consist of 1D linear arrays of 4.5 Hz-vertical geophones using a minigun as source. Passive
methods consist of 2D arrays of seismic three-component sensors. In order to investigate the low-frequency
amplification, the geometry of 2D arrays was accordingly designed, using 16 seismic stations with maximum
aperture of 1 km that recorded many hours of ambient seismic noise. We deployed three 2D arrays, one in the
northern part and two in the southern part of the city. The 1D linear array was dedicated to characterize the
shallower part of “limi rossi”.
With the aim to derive the shear wave velocity profiles, the apparent phase velocity estimated through arrays
technique has been inverted through a neighborhood algorithm
Characterization of the breccia deposits in downtown L’Aquila (Central Italy) through multichannel analysis of surface waves
On April 6th 2009 an Mw 6.3 earthquake hit the historical city of L’Aquila (Central Italy) causing about 300 causalities, more than 39000 homeless and strong damage in the city and in the surrounding villages. L’Aquila downtown suffered Mercalli-Cancani-Sieberg (MCS; Sieberg 1930) intensity > VIII. Heavy damage and collapses
were concentrated in the unreinforced masonry buildings including historical churches.
Starting from June 2009, the Italian Civil Defense Department promoted a microzoning study of the epicentral area, aimed at identifying, at a detailed scale, areas were local seismic amplification could occur due to the characteristics of surface geology.
L’Aquila is founded on a terrace that slopes down moving in the southwest direction, and raises about 50 meters above the Aterno river bed. The terrace is formed by alluvial Quaternary breccias consisting of limestone clasts in a marly matrix. In the northern part of the city the terrace is in contact with outcropping limestone, while moving
toward south, breccias are over imposed to lacustrine sediments formed mainly of silty and sandy layers and minor gravel beds. As found by boreholes, the thickness of the breccias formation ranges from tenths of meters at north to just few meters at south. The uppermost weathered part of breccias outcrops at south and is indicated as “limi
rossi”. The presence of breccias and “limi rossi” in the northern and southern part of the city respectively, is well identified by collected geotechnical data. Shear wave velocity (Vs) are quite high in the northern sector and can reach values of about 1000 m/s, whereas in the southernmost part the Vs of “limi rossi” drops down to 300-400
m/s. The microzoning studies at L’Aquila evidenced the presence of low-frequency (about 0.6 Hz) amplification diffused in the historical center with high amplification factors in the southern area of the city were “limi rossi” outcrops.
We here present the results of multichannel surface waves analysis (MASW) based on active and passive sources.
Active methods consist of 1D linear arrays of 4.5 Hz-vertical geophones using a minigun as source. Passive methods consist of 2D arrays of seismic three-component sensors. In order to investigate the low-frequency
amplification, the geometry of 2D arrays was accordingly designed, using 16 seismic stations with maximum aperture of 1 km that recorded many hours of ambient seismic noise. We deployed three 2D arrays, one in the northern part and two in the southern part of the city. The 1D linear array was dedicated to characterize the shallower part of “limi rossi”.
With the aim to derive the shear wave velocity profiles, the apparent phase velocity estimated through arrays
technique has been inverted through a neighborhood algorithm
Seismic noise in a geologically complex site (L’Aquila, central Italy) to fine-tune the subsoil model for seismic microzonation mapping
We present the fine scale investigations of seismic noise carried out in a geologically complex site in the Aterno
R. Valley (L’Aquila, central Italy). The goals of the study are to point out the efficiency of seismic noise technique
in geologically complex site by comparing those data with other geophysical investigations (active seismic
techniques, gravimetric survey) and geological data (more than 60 well logs and a detailed fine scale geological
mapping), to fine-tune the subsoil model and to locate the geometry of seismic and geological bedrock.
The study area is located in the western part of L’Aquila intramontane plain which was struck by the recent April
6 earthquake (Mw: 6.3). L’Aquila intramontane plain is a typical Quaternary basin of central Apennines and it
is a halfgraben extending in a WNW-ESE direction, along the Aterno River Valley. The carbonate bedrock is
variably displaced by normal faults, with both Apennine (NW-SE) and anti-Apennine (NE-SW) directions, and
by a N-dipping back-thrust. The alluvial deposits consist of more or less coarse gravels, sands and silty clays of
fluvial and alluvial-fan environments organised in lenticular bodies.
The model of subsoil was reconstructed by correlating borehole stratigraphies with data from geophysical tests
(down-hole, cross-hole and microtremor measurements).
In the study area the presence of a double amplification peak is the main characteristics of HVNSR data. This
feature can be related to the presence of two strong impedance contrasts in the deposits filling the Aterno R.
Valley. A first shallow contrast, due to the presence of the gravel layer found in the cross hole data, is responsible
for the high frequency ( > 10Hz) HVNSR peak, while the deeper contrast between recent sedimentary layers and
the limestone, acting as seismic bedrock,k at depth of few tents of meters produces the second peak centered at
3Hz.
The inversion of microtremor data, constrained by stratigraphic logs and seismic in-hole tests (down-hole,
cross-hole), made it possible to demarcate zones with constant Vs and to reconstruct the depth of the carbonate
(or seismic) bedrock; this depth ranged from 0 to 52 m from ground level. The Vs velocities of the alluvial and
slope covers range from 300 m/s to 600 m/s. The Vs velocities in the central sector of the valley exceed 400 m/s;
this is due to the occurrence of gravely lenses, which reach their maximum thickness in this sector.
This study is a good example of how the seismic noise could furnish a useful contribution to fine-tune the subsoil
model also in geologically complex sites
Seismic response of L’Aquila (Central Appennines, Italy) from 2D numerical simulation
Experimental and modeling approaches fulfill complementary needs in the assessment of the seismic soil response.
Here we present some results from 2D simulation performed for the L’Aquila basin (Central Appennines, Italy).
The city of L’Aquila on April 6th, 2009 at 01:32 UTC was struck by a magnitude Mw=6.3 earthquake localized
about 2 kilometers west of the city centre at hypocentral depth 9 km. The city of L’Aquila suffered wide
spread destructive damage in its historical centre where housing is mainly 2 to 3 storey medieval masonry.
Several reinforced concrete buildings built in the late 70s collapsed in the south-west section of the city and also
monumental, historical churches were severely damaged. Because of its location, the ground motion recorded in
the city is strongly influenced by the source rupture mechanism, nonetheless, local amplification are expected to
have influenced the ground shacking. L’Aquila is indeed built over a Quaternary terraced alluvial-lacustrine basin
with a rather complex lithology as well as surface topography.
The 2D seismic modeling of L’Aquila terrace was already performed by several authors along transversally oriented
(NE-SW) geological sections. In this study we present some new results obtained by the use of longitudinal
cross sections (NW-SE) in order to better understand the role of lateral geological heterogeneities as derived by
recent geological and geophysical data. The simulations have been performed using the impedance-operator-based
numerical code.
The models of L’Aquila terrace are based on geological and geophysical investigations performed in the framework
of the micro-zoning activities of the city following the disastrous April 6th 2009 Mw=6.3 earthquake and in
subsequent studies. The depth to the bedrock of the basin is constrained by gravimetric and deep borehole data
with an estimated maximum depth of about 300 m. The basin is filled by silt and silty-clay of lacustrine origin
topped by a breccia layer (BrA) of gravitational-fluvial origin. BrA does not extend continuously over the terrace
and in particular in the southern area of the city it is locally replaced by silt and silty-clay of lacustrine origin with
lens of BrA and gravel with silt. Locally, on the top of the terrace lens of less competent red silt were found by the
recent deep borehole surveys performed in the micro-zoning activities.
We have further constrained our 2D models using the resonance frequencies from noise and earthquake spectral
ratios for selected sites. The wave velocities have been inferred by MASW and cross-hole analyses.
We have compared the spectral ratios obtained from SH, P-SV and Rayleigh incident waves field in the range
0 -90 to the observed spectral ratios computed using the earthquake aftershocks recorded by the micro-zoning
portable network. The modeling results are able to match the resonance frequency obtained by seismological data
and to verify the role of the reversal in the velocity-depth profile and the lateral continuity of the top fast layer
(BrA)
PAX8 (paired box 8)
Review on PAX8 (paired box 8), with data on DNA, on the protein encoded, and where the gene is implicated
Role of microRNAs in the main molecular pathways of hepatocellular carcinoma
Hepatocellular carcinoma (HCC) is the most common primary liver malignant neoplasia. HCC is characterized by a poor prognosis. The need to find new molecular markers for its diagnosis and prognosis has led to a progressive increase in the number of scientific studies on this topic. MicroRNAs (miRNAs) are small noncoding RNA that play a role in almost all main cellular pathways. miRNAs are involved in the regulation of expression of the major tumor-related genes in carcinogenesis, acting as oncogenes or tumor suppressor genes. The aim of this review was to identify papers published in 2017 investigating the role of miRNAs in HCC tumorigenesis. miRNAs were classified according to their role in the main molecular pathways involved in HCC tumorigenesis: (1) mTOR; (2) Wnt; (3) JAK/STAT; (4) apoptosis; and (5) MAPK. The role of miRNAs in prognosis/response prediction was taken into consideration. Bearing in mind that the analysis of miRNAs in serum and other body fluids would be crucial for clinical management, the role of circulating miRNAs in HCC patients was also investigated. The most represented miRNA-regulated pathway in HCC is mTOR, but apoptosis, Wnt, JAK/STAT or MAPK pathways are also influenced by miRNA expression levels. These miRNAs could thus be used in clinical practice as diagnostic, prognostic or therapeutic targets for HCC treatment
Prevalence of the single-nucleotide polymorphism rs11554137 (IDH1105GGT) in brain tumors of a cohort of Italian patients
IDH mutational status is required for proper diagnosis according to the WHO criteria revised in 2016. The single nucleotide polymorphism (SNP) rs11554137 (IDH1105GGT) at codon 105 of IDH1 has been reported in patients with several tumor types, including those with glioma. The aim of this study is to investigate the prevalence of IDH1105GGTin a cohort of brain tumors, and its association with clinicopathologic features and IDH1 and IDH2 missense mutations. Exon 4 of IDH1 and IDH2 was analyzed in a series of brain tumors classified according to current WHO criteria. DNA from control individuals was analyzed to infer the prevalence of IDH1105GGTin the reference population. Analysis was performed using next generation sequencing. IDH1105GGTwas three times more frequent in patients with tumors (44/293 cases, 15.0%) vs. population controls (6/109, 5.5%) (p = 0.0102). IDH1105GGTwas more frequent in grade III tumors (26.1%) compared to grade II (10.9%, p = 0.038) and grade IV tumors (13.7%, p = 0.041). IDH1105GGTwas more frequent in grade II and III tumors without an IDH tumor missense mutation (43.8%) than in those with (11.5%, p = 0.005). The IDH1105GGTSNP likely represents an important genetic marker, worthy of additional investigation to better understand the clinical and biological features of IDH-WT infiltrating gliomas
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